2322 lines
62 KiB
C
2322 lines
62 KiB
C
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/*****************************************************************************
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* Copyright 2004 - 2008 Broadcom Corporation. All rights reserved.
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*
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* Unless you and Broadcom execute a separate written software license
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* agreement governing use of this software, this software is licensed to you
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* under the terms of the GNU General Public License version 2, available at
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* http://www.broadcom.com/licenses/GPLv2.php (the "GPL").
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*
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* Notwithstanding the above, under no circumstances may you combine this
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* software in any way with any other Broadcom software provided under a
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* license other than the GPL, without Broadcom's express prior written
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* consent.
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*****************************************************************************/
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/****************************************************************************/
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/**
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* @file dma.c
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*
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* @brief Implements the DMA interface.
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*/
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/****************************************************************************/
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/* ---- Include Files ---------------------------------------------------- */
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#include <linux/module.h>
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#include <linux/device.h>
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#include <linux/dma-mapping.h>
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#include <linux/interrupt.h>
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#include <linux/irqreturn.h>
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#include <linux/proc_fs.h>
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#include <mach/timer.h>
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#include <linux/mm.h>
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#include <linux/pfn.h>
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#include <asm/atomic.h>
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#include <mach/dma.h>
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/* I don't quite understand why dc4 fails when this is set to 1 and DMA is enabled */
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/* especially since dc4 doesn't use kmalloc'd memory. */
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#define ALLOW_MAP_OF_KMALLOC_MEMORY 0
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/* ---- Public Variables ------------------------------------------------- */
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/* ---- Private Constants and Types -------------------------------------- */
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#define MAKE_HANDLE(controllerIdx, channelIdx) (((controllerIdx) << 4) | (channelIdx))
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#define CONTROLLER_FROM_HANDLE(handle) (((handle) >> 4) & 0x0f)
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#define CHANNEL_FROM_HANDLE(handle) ((handle) & 0x0f)
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#define DMA_MAP_DEBUG 0
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#if DMA_MAP_DEBUG
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# define DMA_MAP_PRINT(fmt, args...) printk("%s: " fmt, __func__, ## args)
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#else
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# define DMA_MAP_PRINT(fmt, args...)
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#endif
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/* ---- Private Variables ------------------------------------------------ */
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static DMA_Global_t gDMA;
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static struct proc_dir_entry *gDmaDir;
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static atomic_t gDmaStatMemTypeKmalloc = ATOMIC_INIT(0);
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static atomic_t gDmaStatMemTypeVmalloc = ATOMIC_INIT(0);
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static atomic_t gDmaStatMemTypeUser = ATOMIC_INIT(0);
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static atomic_t gDmaStatMemTypeCoherent = ATOMIC_INIT(0);
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#include "dma_device.c"
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/* ---- Private Function Prototypes -------------------------------------- */
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/* ---- Functions ------------------------------------------------------- */
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/****************************************************************************/
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/**
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* Displays information for /proc/dma/mem-type
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*/
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/****************************************************************************/
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static int dma_proc_read_mem_type(char *buf, char **start, off_t offset,
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int count, int *eof, void *data)
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{
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int len = 0;
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len += sprintf(buf + len, "dma_map_mem statistics\n");
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len +=
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sprintf(buf + len, "coherent: %d\n",
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atomic_read(&gDmaStatMemTypeCoherent));
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len +=
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sprintf(buf + len, "kmalloc: %d\n",
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atomic_read(&gDmaStatMemTypeKmalloc));
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len +=
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sprintf(buf + len, "vmalloc: %d\n",
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atomic_read(&gDmaStatMemTypeVmalloc));
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len +=
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sprintf(buf + len, "user: %d\n",
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atomic_read(&gDmaStatMemTypeUser));
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return len;
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}
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/****************************************************************************/
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/**
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* Displays information for /proc/dma/channels
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*/
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/****************************************************************************/
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static int dma_proc_read_channels(char *buf, char **start, off_t offset,
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int count, int *eof, void *data)
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{
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int controllerIdx;
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int channelIdx;
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int limit = count - 200;
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int len = 0;
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DMA_Channel_t *channel;
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if (down_interruptible(&gDMA.lock) < 0) {
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return -ERESTARTSYS;
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}
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for (controllerIdx = 0; controllerIdx < DMA_NUM_CONTROLLERS;
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controllerIdx++) {
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for (channelIdx = 0; channelIdx < DMA_NUM_CHANNELS;
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channelIdx++) {
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if (len >= limit) {
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break;
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}
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channel =
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&gDMA.controller[controllerIdx].channel[channelIdx];
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len +=
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sprintf(buf + len, "%d:%d ", controllerIdx,
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channelIdx);
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if ((channel->flags & DMA_CHANNEL_FLAG_IS_DEDICATED) !=
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0) {
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len +=
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sprintf(buf + len, "Dedicated for %s ",
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DMA_gDeviceAttribute[channel->
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devType].name);
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} else {
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len += sprintf(buf + len, "Shared ");
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}
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if ((channel->flags & DMA_CHANNEL_FLAG_NO_ISR) != 0) {
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len += sprintf(buf + len, "No ISR ");
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}
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if ((channel->flags & DMA_CHANNEL_FLAG_LARGE_FIFO) != 0) {
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len += sprintf(buf + len, "Fifo: 128 ");
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} else {
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len += sprintf(buf + len, "Fifo: 64 ");
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}
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if ((channel->flags & DMA_CHANNEL_FLAG_IN_USE) != 0) {
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len +=
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sprintf(buf + len, "InUse by %s",
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DMA_gDeviceAttribute[channel->
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devType].name);
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#if (DMA_DEBUG_TRACK_RESERVATION)
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len +=
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sprintf(buf + len, " (%s:%d)",
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channel->fileName,
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channel->lineNum);
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#endif
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} else {
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len += sprintf(buf + len, "Avail ");
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}
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if (channel->lastDevType != DMA_DEVICE_NONE) {
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len +=
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sprintf(buf + len, "Last use: %s ",
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DMA_gDeviceAttribute[channel->
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lastDevType].
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name);
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}
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len += sprintf(buf + len, "\n");
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}
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}
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up(&gDMA.lock);
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*eof = 1;
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return len;
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}
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/****************************************************************************/
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/**
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* Displays information for /proc/dma/devices
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*/
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/****************************************************************************/
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static int dma_proc_read_devices(char *buf, char **start, off_t offset,
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int count, int *eof, void *data)
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{
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int limit = count - 200;
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int len = 0;
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int devIdx;
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if (down_interruptible(&gDMA.lock) < 0) {
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return -ERESTARTSYS;
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}
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for (devIdx = 0; devIdx < DMA_NUM_DEVICE_ENTRIES; devIdx++) {
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DMA_DeviceAttribute_t *devAttr = &DMA_gDeviceAttribute[devIdx];
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if (devAttr->name == NULL) {
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continue;
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}
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if (len >= limit) {
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break;
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}
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len += sprintf(buf + len, "%-12s ", devAttr->name);
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if ((devAttr->flags & DMA_DEVICE_FLAG_IS_DEDICATED) != 0) {
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len +=
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sprintf(buf + len, "Dedicated %d:%d ",
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devAttr->dedicatedController,
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devAttr->dedicatedChannel);
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} else {
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len += sprintf(buf + len, "Shared DMA:");
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if ((devAttr->flags & DMA_DEVICE_FLAG_ON_DMA0) != 0) {
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len += sprintf(buf + len, "0");
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}
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if ((devAttr->flags & DMA_DEVICE_FLAG_ON_DMA1) != 0) {
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len += sprintf(buf + len, "1");
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}
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len += sprintf(buf + len, " ");
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}
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if ((devAttr->flags & DMA_DEVICE_FLAG_NO_ISR) != 0) {
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len += sprintf(buf + len, "NoISR ");
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}
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if ((devAttr->flags & DMA_DEVICE_FLAG_ALLOW_LARGE_FIFO) != 0) {
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len += sprintf(buf + len, "Allow-128 ");
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}
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len +=
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sprintf(buf + len,
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"Xfer #: %Lu Ticks: %Lu Bytes: %Lu DescLen: %u\n",
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devAttr->numTransfers, devAttr->transferTicks,
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devAttr->transferBytes,
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devAttr->ring.bytesAllocated);
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}
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up(&gDMA.lock);
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*eof = 1;
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return len;
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}
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/****************************************************************************/
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/**
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* Determines if a DMA_Device_t is "valid".
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*
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* @return
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* TRUE - dma device is valid
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* FALSE - dma device isn't valid
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*/
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/****************************************************************************/
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static inline int IsDeviceValid(DMA_Device_t device)
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{
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return (device >= 0) && (device < DMA_NUM_DEVICE_ENTRIES);
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}
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/****************************************************************************/
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/**
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* Translates a DMA handle into a pointer to a channel.
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*
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* @return
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* non-NULL - pointer to DMA_Channel_t
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* NULL - DMA Handle was invalid
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*/
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/****************************************************************************/
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static inline DMA_Channel_t *HandleToChannel(DMA_Handle_t handle)
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{
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int controllerIdx;
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int channelIdx;
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controllerIdx = CONTROLLER_FROM_HANDLE(handle);
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channelIdx = CHANNEL_FROM_HANDLE(handle);
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if ((controllerIdx > DMA_NUM_CONTROLLERS)
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|| (channelIdx > DMA_NUM_CHANNELS)) {
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return NULL;
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}
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return &gDMA.controller[controllerIdx].channel[channelIdx];
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}
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/****************************************************************************/
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/**
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* Interrupt handler which is called to process DMA interrupts.
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*/
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/****************************************************************************/
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static irqreturn_t dma_interrupt_handler(int irq, void *dev_id)
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{
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DMA_Channel_t *channel;
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DMA_DeviceAttribute_t *devAttr;
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int irqStatus;
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channel = (DMA_Channel_t *) dev_id;
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/* Figure out why we were called, and knock down the interrupt */
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irqStatus = dmacHw_getInterruptStatus(channel->dmacHwHandle);
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dmacHw_clearInterrupt(channel->dmacHwHandle);
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if ((channel->devType < 0)
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|| (channel->devType > DMA_NUM_DEVICE_ENTRIES)) {
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printk(KERN_ERR "dma_interrupt_handler: Invalid devType: %d\n",
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channel->devType);
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return IRQ_NONE;
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}
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devAttr = &DMA_gDeviceAttribute[channel->devType];
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/* Update stats */
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if ((irqStatus & dmacHw_INTERRUPT_STATUS_TRANS) != 0) {
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devAttr->transferTicks +=
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(timer_get_tick_count() - devAttr->transferStartTime);
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}
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if ((irqStatus & dmacHw_INTERRUPT_STATUS_ERROR) != 0) {
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printk(KERN_ERR
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"dma_interrupt_handler: devType :%d DMA error (%s)\n",
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channel->devType, devAttr->name);
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} else {
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devAttr->numTransfers++;
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devAttr->transferBytes += devAttr->numBytes;
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}
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/* Call any installed handler */
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if (devAttr->devHandler != NULL) {
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devAttr->devHandler(channel->devType, irqStatus,
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devAttr->userData);
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}
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return IRQ_HANDLED;
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}
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/****************************************************************************/
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/**
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* Allocates memory to hold a descriptor ring. The descriptor ring then
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* needs to be populated by making one or more calls to
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* dna_add_descriptors.
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*
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* The returned descriptor ring will be automatically initialized.
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*
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* @return
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* 0 Descriptor ring was allocated successfully
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* -EINVAL Invalid parameters passed in
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* -ENOMEM Unable to allocate memory for the desired number of descriptors.
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*/
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/****************************************************************************/
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int dma_alloc_descriptor_ring(DMA_DescriptorRing_t *ring, /* Descriptor ring to populate */
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int numDescriptors /* Number of descriptors that need to be allocated. */
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) {
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size_t bytesToAlloc = dmacHw_descriptorLen(numDescriptors);
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if ((ring == NULL) || (numDescriptors <= 0)) {
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return -EINVAL;
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}
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ring->physAddr = 0;
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ring->descriptorsAllocated = 0;
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ring->bytesAllocated = 0;
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ring->virtAddr = dma_alloc_writecombine(NULL,
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bytesToAlloc,
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&ring->physAddr,
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GFP_KERNEL);
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if (ring->virtAddr == NULL) {
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return -ENOMEM;
|
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}
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ring->bytesAllocated = bytesToAlloc;
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ring->descriptorsAllocated = numDescriptors;
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return dma_init_descriptor_ring(ring, numDescriptors);
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}
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EXPORT_SYMBOL(dma_alloc_descriptor_ring);
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/****************************************************************************/
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/**
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* Releases the memory which was previously allocated for a descriptor ring.
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*/
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/****************************************************************************/
|
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|
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void dma_free_descriptor_ring(DMA_DescriptorRing_t *ring /* Descriptor to release */
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) {
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if (ring->virtAddr != NULL) {
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dma_free_writecombine(NULL,
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ring->bytesAllocated,
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ring->virtAddr, ring->physAddr);
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}
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ring->bytesAllocated = 0;
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ring->descriptorsAllocated = 0;
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ring->virtAddr = NULL;
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ring->physAddr = 0;
|
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}
|
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|
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EXPORT_SYMBOL(dma_free_descriptor_ring);
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|
|
||
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/****************************************************************************/
|
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|
/**
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* Initializes a descriptor ring, so that descriptors can be added to it.
|
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* Once a descriptor ring has been allocated, it may be reinitialized for
|
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* use with additional/different regions of memory.
|
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|
*
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* Note that if 7 descriptors are allocated, it's perfectly acceptable to
|
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|
* initialize the ring with a smaller number of descriptors. The amount
|
||
|
* of memory allocated for the descriptor ring will not be reduced, and
|
||
|
* the descriptor ring may be reinitialized later
|
||
|
*
|
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|
* @return
|
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|
* 0 Descriptor ring was initialized successfully
|
||
|
* -ENOMEM The descriptor which was passed in has insufficient space
|
||
|
* to hold the desired number of descriptors.
|
||
|
*/
|
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|
/****************************************************************************/
|
||
|
|
||
|
int dma_init_descriptor_ring(DMA_DescriptorRing_t *ring, /* Descriptor ring to initialize */
|
||
|
int numDescriptors /* Number of descriptors to initialize. */
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||
|
) {
|
||
|
if (ring->virtAddr == NULL) {
|
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|
return -EINVAL;
|
||
|
}
|
||
|
if (dmacHw_initDescriptor(ring->virtAddr,
|
||
|
ring->physAddr,
|
||
|
ring->bytesAllocated, numDescriptors) < 0) {
|
||
|
printk(KERN_ERR
|
||
|
"dma_init_descriptor_ring: dmacHw_initDescriptor failed\n");
|
||
|
return -ENOMEM;
|
||
|
}
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
EXPORT_SYMBOL(dma_init_descriptor_ring);
|
||
|
|
||
|
/****************************************************************************/
|
||
|
/**
|
||
|
* Determines the number of descriptors which would be required for a
|
||
|
* transfer of the indicated memory region.
|
||
|
*
|
||
|
* This function also needs to know which DMA device this transfer will
|
||
|
* be destined for, so that the appropriate DMA configuration can be retrieved.
|
||
|
* DMA parameters such as transfer width, and whether this is a memory-to-memory
|
||
|
* or memory-to-peripheral, etc can all affect the actual number of descriptors
|
||
|
* required.
|
||
|
*
|
||
|
* @return
|
||
|
* > 0 Returns the number of descriptors required for the indicated transfer
|
||
|
* -ENODEV - Device handed in is invalid.
|
||
|
* -EINVAL Invalid parameters
|
||
|
* -ENOMEM Memory exhausted
|
||
|
*/
|
||
|
/****************************************************************************/
|
||
|
|
||
|
int dma_calculate_descriptor_count(DMA_Device_t device, /* DMA Device that this will be associated with */
|
||
|
dma_addr_t srcData, /* Place to get data to write to device */
|
||
|
dma_addr_t dstData, /* Pointer to device data address */
|
||
|
size_t numBytes /* Number of bytes to transfer to the device */
|
||
|
) {
|
||
|
int numDescriptors;
|
||
|
DMA_DeviceAttribute_t *devAttr;
|
||
|
|
||
|
if (!IsDeviceValid(device)) {
|
||
|
return -ENODEV;
|
||
|
}
|
||
|
devAttr = &DMA_gDeviceAttribute[device];
|
||
|
|
||
|
numDescriptors = dmacHw_calculateDescriptorCount(&devAttr->config,
|
||
|
(void *)srcData,
|
||
|
(void *)dstData,
|
||
|
numBytes);
|
||
|
if (numDescriptors < 0) {
|
||
|
printk(KERN_ERR
|
||
|
"dma_calculate_descriptor_count: dmacHw_calculateDescriptorCount failed\n");
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
|
||
|
return numDescriptors;
|
||
|
}
|
||
|
|
||
|
EXPORT_SYMBOL(dma_calculate_descriptor_count);
|
||
|
|
||
|
/****************************************************************************/
|
||
|
/**
|
||
|
* Adds a region of memory to the descriptor ring. Note that it may take
|
||
|
* multiple descriptors for each region of memory. It is the callers
|
||
|
* responsibility to allocate a sufficiently large descriptor ring.
|
||
|
*
|
||
|
* @return
|
||
|
* 0 Descriptors were added successfully
|
||
|
* -ENODEV Device handed in is invalid.
|
||
|
* -EINVAL Invalid parameters
|
||
|
* -ENOMEM Memory exhausted
|
||
|
*/
|
||
|
/****************************************************************************/
|
||
|
|
||
|
int dma_add_descriptors(DMA_DescriptorRing_t *ring, /* Descriptor ring to add descriptors to */
|
||
|
DMA_Device_t device, /* DMA Device that descriptors are for */
|
||
|
dma_addr_t srcData, /* Place to get data (memory or device) */
|
||
|
dma_addr_t dstData, /* Place to put data (memory or device) */
|
||
|
size_t numBytes /* Number of bytes to transfer to the device */
|
||
|
) {
|
||
|
int rc;
|
||
|
DMA_DeviceAttribute_t *devAttr;
|
||
|
|
||
|
if (!IsDeviceValid(device)) {
|
||
|
return -ENODEV;
|
||
|
}
|
||
|
devAttr = &DMA_gDeviceAttribute[device];
|
||
|
|
||
|
rc = dmacHw_setDataDescriptor(&devAttr->config,
|
||
|
ring->virtAddr,
|
||
|
(void *)srcData,
|
||
|
(void *)dstData, numBytes);
|
||
|
if (rc < 0) {
|
||
|
printk(KERN_ERR
|
||
|
"dma_add_descriptors: dmacHw_setDataDescriptor failed with code: %d\n",
|
||
|
rc);
|
||
|
return -ENOMEM;
|
||
|
}
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
EXPORT_SYMBOL(dma_add_descriptors);
|
||
|
|
||
|
/****************************************************************************/
|
||
|
/**
|
||
|
* Sets the descriptor ring associated with a device.
|
||
|
*
|
||
|
* Once set, the descriptor ring will be associated with the device, even
|
||
|
* across channel request/free calls. Passing in a NULL descriptor ring
|
||
|
* will release any descriptor ring currently associated with the device.
|
||
|
*
|
||
|
* Note: If you call dma_transfer, or one of the other dma_alloc_ functions
|
||
|
* the descriptor ring may be released and reallocated.
|
||
|
*
|
||
|
* Note: This function will release the descriptor memory for any current
|
||
|
* descriptor ring associated with this device.
|
||
|
*
|
||
|
* @return
|
||
|
* 0 Descriptors were added successfully
|
||
|
* -ENODEV Device handed in is invalid.
|
||
|
*/
|
||
|
/****************************************************************************/
|
||
|
|
||
|
int dma_set_device_descriptor_ring(DMA_Device_t device, /* Device to update the descriptor ring for. */
|
||
|
DMA_DescriptorRing_t *ring /* Descriptor ring to add descriptors to */
|
||
|
) {
|
||
|
DMA_DeviceAttribute_t *devAttr;
|
||
|
|
||
|
if (!IsDeviceValid(device)) {
|
||
|
return -ENODEV;
|
||
|
}
|
||
|
devAttr = &DMA_gDeviceAttribute[device];
|
||
|
|
||
|
/* Free the previously allocated descriptor ring */
|
||
|
|
||
|
dma_free_descriptor_ring(&devAttr->ring);
|
||
|
|
||
|
if (ring != NULL) {
|
||
|
/* Copy in the new one */
|
||
|
|
||
|
devAttr->ring = *ring;
|
||
|
}
|
||
|
|
||
|
/* Set things up so that if dma_transfer is called then this descriptor */
|
||
|
/* ring will get freed. */
|
||
|
|
||
|
devAttr->prevSrcData = 0;
|
||
|
devAttr->prevDstData = 0;
|
||
|
devAttr->prevNumBytes = 0;
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
EXPORT_SYMBOL(dma_set_device_descriptor_ring);
|
||
|
|
||
|
/****************************************************************************/
|
||
|
/**
|
||
|
* Retrieves the descriptor ring associated with a device.
|
||
|
*
|
||
|
* @return
|
||
|
* 0 Descriptors were added successfully
|
||
|
* -ENODEV Device handed in is invalid.
|
||
|
*/
|
||
|
/****************************************************************************/
|
||
|
|
||
|
int dma_get_device_descriptor_ring(DMA_Device_t device, /* Device to retrieve the descriptor ring for. */
|
||
|
DMA_DescriptorRing_t *ring /* Place to store retrieved ring */
|
||
|
) {
|
||
|
DMA_DeviceAttribute_t *devAttr;
|
||
|
|
||
|
memset(ring, 0, sizeof(*ring));
|
||
|
|
||
|
if (!IsDeviceValid(device)) {
|
||
|
return -ENODEV;
|
||
|
}
|
||
|
devAttr = &DMA_gDeviceAttribute[device];
|
||
|
|
||
|
*ring = devAttr->ring;
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
EXPORT_SYMBOL(dma_get_device_descriptor_ring);
|
||
|
|
||
|
/****************************************************************************/
|
||
|
/**
|
||
|
* Configures a DMA channel.
|
||
|
*
|
||
|
* @return
|
||
|
* >= 0 - Initialization was successfull.
|
||
|
*
|
||
|
* -EBUSY - Device is currently being used.
|
||
|
* -ENODEV - Device handed in is invalid.
|
||
|
*/
|
||
|
/****************************************************************************/
|
||
|
|
||
|
static int ConfigChannel(DMA_Handle_t handle)
|
||
|
{
|
||
|
DMA_Channel_t *channel;
|
||
|
DMA_DeviceAttribute_t *devAttr;
|
||
|
int controllerIdx;
|
||
|
|
||
|
channel = HandleToChannel(handle);
|
||
|
if (channel == NULL) {
|
||
|
return -ENODEV;
|
||
|
}
|
||
|
devAttr = &DMA_gDeviceAttribute[channel->devType];
|
||
|
controllerIdx = CONTROLLER_FROM_HANDLE(handle);
|
||
|
|
||
|
if ((devAttr->flags & DMA_DEVICE_FLAG_PORT_PER_DMAC) != 0) {
|
||
|
if (devAttr->config.transferType ==
|
||
|
dmacHw_TRANSFER_TYPE_MEM_TO_PERIPHERAL) {
|
||
|
devAttr->config.dstPeripheralPort =
|
||
|
devAttr->dmacPort[controllerIdx];
|
||
|
} else if (devAttr->config.transferType ==
|
||
|
dmacHw_TRANSFER_TYPE_PERIPHERAL_TO_MEM) {
|
||
|
devAttr->config.srcPeripheralPort =
|
||
|
devAttr->dmacPort[controllerIdx];
|
||
|
}
|
||
|
}
|
||
|
|
||
|
if (dmacHw_configChannel(channel->dmacHwHandle, &devAttr->config) != 0) {
|
||
|
printk(KERN_ERR "ConfigChannel: dmacHw_configChannel failed\n");
|
||
|
return -EIO;
|
||
|
}
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
/****************************************************************************/
|
||
|
/**
|
||
|
* Intializes all of the data structures associated with the DMA.
|
||
|
* @return
|
||
|
* >= 0 - Initialization was successfull.
|
||
|
*
|
||
|
* -EBUSY - Device is currently being used.
|
||
|
* -ENODEV - Device handed in is invalid.
|
||
|
*/
|
||
|
/****************************************************************************/
|
||
|
|
||
|
int dma_init(void)
|
||
|
{
|
||
|
int rc = 0;
|
||
|
int controllerIdx;
|
||
|
int channelIdx;
|
||
|
DMA_Device_t devIdx;
|
||
|
DMA_Channel_t *channel;
|
||
|
DMA_Handle_t dedicatedHandle;
|
||
|
|
||
|
memset(&gDMA, 0, sizeof(gDMA));
|
||
|
|
||
|
init_MUTEX_LOCKED(&gDMA.lock);
|
||
|
init_waitqueue_head(&gDMA.freeChannelQ);
|
||
|
|
||
|
/* Initialize the Hardware */
|
||
|
|
||
|
dmacHw_initDma();
|
||
|
|
||
|
/* Start off by marking all of the DMA channels as shared. */
|
||
|
|
||
|
for (controllerIdx = 0; controllerIdx < DMA_NUM_CONTROLLERS;
|
||
|
controllerIdx++) {
|
||
|
for (channelIdx = 0; channelIdx < DMA_NUM_CHANNELS;
|
||
|
channelIdx++) {
|
||
|
channel =
|
||
|
&gDMA.controller[controllerIdx].channel[channelIdx];
|
||
|
|
||
|
channel->flags = 0;
|
||
|
channel->devType = DMA_DEVICE_NONE;
|
||
|
channel->lastDevType = DMA_DEVICE_NONE;
|
||
|
|
||
|
#if (DMA_DEBUG_TRACK_RESERVATION)
|
||
|
channel->fileName = "";
|
||
|
channel->lineNum = 0;
|
||
|
#endif
|
||
|
|
||
|
channel->dmacHwHandle =
|
||
|
dmacHw_getChannelHandle(dmacHw_MAKE_CHANNEL_ID
|
||
|
(controllerIdx,
|
||
|
channelIdx));
|
||
|
dmacHw_initChannel(channel->dmacHwHandle);
|
||
|
}
|
||
|
}
|
||
|
|
||
|
/* Record any special attributes that channels may have */
|
||
|
|
||
|
gDMA.controller[0].channel[0].flags |= DMA_CHANNEL_FLAG_LARGE_FIFO;
|
||
|
gDMA.controller[0].channel[1].flags |= DMA_CHANNEL_FLAG_LARGE_FIFO;
|
||
|
gDMA.controller[1].channel[0].flags |= DMA_CHANNEL_FLAG_LARGE_FIFO;
|
||
|
gDMA.controller[1].channel[1].flags |= DMA_CHANNEL_FLAG_LARGE_FIFO;
|
||
|
|
||
|
/* Now walk through and record the dedicated channels. */
|
||
|
|
||
|
for (devIdx = 0; devIdx < DMA_NUM_DEVICE_ENTRIES; devIdx++) {
|
||
|
DMA_DeviceAttribute_t *devAttr = &DMA_gDeviceAttribute[devIdx];
|
||
|
|
||
|
if (((devAttr->flags & DMA_DEVICE_FLAG_NO_ISR) != 0)
|
||
|
&& ((devAttr->flags & DMA_DEVICE_FLAG_IS_DEDICATED) == 0)) {
|
||
|
printk(KERN_ERR
|
||
|
"DMA Device: %s Can only request NO_ISR for dedicated devices\n",
|
||
|
devAttr->name);
|
||
|
rc = -EINVAL;
|
||
|
goto out;
|
||
|
}
|
||
|
|
||
|
if ((devAttr->flags & DMA_DEVICE_FLAG_IS_DEDICATED) != 0) {
|
||
|
/* This is a dedicated device. Mark the channel as being reserved. */
|
||
|
|
||
|
if (devAttr->dedicatedController >= DMA_NUM_CONTROLLERS) {
|
||
|
printk(KERN_ERR
|
||
|
"DMA Device: %s DMA Controller %d is out of range\n",
|
||
|
devAttr->name,
|
||
|
devAttr->dedicatedController);
|
||
|
rc = -EINVAL;
|
||
|
goto out;
|
||
|
}
|
||
|
|
||
|
if (devAttr->dedicatedChannel >= DMA_NUM_CHANNELS) {
|
||
|
printk(KERN_ERR
|
||
|
"DMA Device: %s DMA Channel %d is out of range\n",
|
||
|
devAttr->name,
|
||
|
devAttr->dedicatedChannel);
|
||
|
rc = -EINVAL;
|
||
|
goto out;
|
||
|
}
|
||
|
|
||
|
dedicatedHandle =
|
||
|
MAKE_HANDLE(devAttr->dedicatedController,
|
||
|
devAttr->dedicatedChannel);
|
||
|
channel = HandleToChannel(dedicatedHandle);
|
||
|
|
||
|
if ((channel->flags & DMA_CHANNEL_FLAG_IS_DEDICATED) !=
|
||
|
0) {
|
||
|
printk
|
||
|
("DMA Device: %s attempting to use same DMA Controller:Channel (%d:%d) as %s\n",
|
||
|
devAttr->name,
|
||
|
devAttr->dedicatedController,
|
||
|
devAttr->dedicatedChannel,
|
||
|
DMA_gDeviceAttribute[channel->devType].
|
||
|
name);
|
||
|
rc = -EBUSY;
|
||
|
goto out;
|
||
|
}
|
||
|
|
||
|
channel->flags |= DMA_CHANNEL_FLAG_IS_DEDICATED;
|
||
|
channel->devType = devIdx;
|
||
|
|
||
|
if (devAttr->flags & DMA_DEVICE_FLAG_NO_ISR) {
|
||
|
channel->flags |= DMA_CHANNEL_FLAG_NO_ISR;
|
||
|
}
|
||
|
|
||
|
/* For dedicated channels, we can go ahead and configure the DMA channel now */
|
||
|
/* as well. */
|
||
|
|
||
|
ConfigChannel(dedicatedHandle);
|
||
|
}
|
||
|
}
|
||
|
|
||
|
/* Go through and register the interrupt handlers */
|
||
|
|
||
|
for (controllerIdx = 0; controllerIdx < DMA_NUM_CONTROLLERS;
|
||
|
controllerIdx++) {
|
||
|
for (channelIdx = 0; channelIdx < DMA_NUM_CHANNELS;
|
||
|
channelIdx++) {
|
||
|
channel =
|
||
|
&gDMA.controller[controllerIdx].channel[channelIdx];
|
||
|
|
||
|
if ((channel->flags & DMA_CHANNEL_FLAG_NO_ISR) == 0) {
|
||
|
snprintf(channel->name, sizeof(channel->name),
|
||
|
"dma %d:%d %s", controllerIdx,
|
||
|
channelIdx,
|
||
|
channel->devType ==
|
||
|
DMA_DEVICE_NONE ? "" :
|
||
|
DMA_gDeviceAttribute[channel->devType].
|
||
|
name);
|
||
|
|
||
|
rc =
|
||
|
request_irq(IRQ_DMA0C0 +
|
||
|
(controllerIdx *
|
||
|
DMA_NUM_CHANNELS) +
|
||
|
channelIdx,
|
||
|
dma_interrupt_handler,
|
||
|
IRQF_DISABLED, channel->name,
|
||
|
channel);
|
||
|
if (rc != 0) {
|
||
|
printk(KERN_ERR
|
||
|
"request_irq for IRQ_DMA%dC%d failed\n",
|
||
|
controllerIdx, channelIdx);
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
|
||
|
/* Create /proc/dma/channels and /proc/dma/devices */
|
||
|
|
||
|
gDmaDir = create_proc_entry("dma", S_IFDIR | S_IRUGO | S_IXUGO, NULL);
|
||
|
|
||
|
if (gDmaDir == NULL) {
|
||
|
printk(KERN_ERR "Unable to create /proc/dma\n");
|
||
|
} else {
|
||
|
create_proc_read_entry("channels", 0, gDmaDir,
|
||
|
dma_proc_read_channels, NULL);
|
||
|
create_proc_read_entry("devices", 0, gDmaDir,
|
||
|
dma_proc_read_devices, NULL);
|
||
|
create_proc_read_entry("mem-type", 0, gDmaDir,
|
||
|
dma_proc_read_mem_type, NULL);
|
||
|
}
|
||
|
|
||
|
out:
|
||
|
|
||
|
up(&gDMA.lock);
|
||
|
|
||
|
return rc;
|
||
|
}
|
||
|
|
||
|
/****************************************************************************/
|
||
|
/**
|
||
|
* Reserves a channel for use with @a dev. If the device is setup to use
|
||
|
* a shared channel, then this function will block until a free channel
|
||
|
* becomes available.
|
||
|
*
|
||
|
* @return
|
||
|
* >= 0 - A valid DMA Handle.
|
||
|
* -EBUSY - Device is currently being used.
|
||
|
* -ENODEV - Device handed in is invalid.
|
||
|
*/
|
||
|
/****************************************************************************/
|
||
|
|
||
|
#if (DMA_DEBUG_TRACK_RESERVATION)
|
||
|
DMA_Handle_t dma_request_channel_dbg
|
||
|
(DMA_Device_t dev, const char *fileName, int lineNum)
|
||
|
#else
|
||
|
DMA_Handle_t dma_request_channel(DMA_Device_t dev)
|
||
|
#endif
|
||
|
{
|
||
|
DMA_Handle_t handle;
|
||
|
DMA_DeviceAttribute_t *devAttr;
|
||
|
DMA_Channel_t *channel;
|
||
|
int controllerIdx;
|
||
|
int controllerIdx2;
|
||
|
int channelIdx;
|
||
|
|
||
|
if (down_interruptible(&gDMA.lock) < 0) {
|
||
|
return -ERESTARTSYS;
|
||
|
}
|
||
|
|
||
|
if ((dev < 0) || (dev >= DMA_NUM_DEVICE_ENTRIES)) {
|
||
|
handle = -ENODEV;
|
||
|
goto out;
|
||
|
}
|
||
|
devAttr = &DMA_gDeviceAttribute[dev];
|
||
|
|
||
|
#if (DMA_DEBUG_TRACK_RESERVATION)
|
||
|
{
|
||
|
char *s;
|
||
|
|
||
|
s = strrchr(fileName, '/');
|
||
|
if (s != NULL) {
|
||
|
fileName = s + 1;
|
||
|
}
|
||
|
}
|
||
|
#endif
|
||
|
if ((devAttr->flags & DMA_DEVICE_FLAG_IN_USE) != 0) {
|
||
|
/* This device has already been requested and not been freed */
|
||
|
|
||
|
printk(KERN_ERR "%s: device %s is already requested\n",
|
||
|
__func__, devAttr->name);
|
||
|
handle = -EBUSY;
|
||
|
goto out;
|
||
|
}
|
||
|
|
||
|
if ((devAttr->flags & DMA_DEVICE_FLAG_IS_DEDICATED) != 0) {
|
||
|
/* This device has a dedicated channel. */
|
||
|
|
||
|
channel =
|
||
|
&gDMA.controller[devAttr->dedicatedController].
|
||
|
channel[devAttr->dedicatedChannel];
|
||
|
if ((channel->flags & DMA_CHANNEL_FLAG_IN_USE) != 0) {
|
||
|
handle = -EBUSY;
|
||
|
goto out;
|
||
|
}
|
||
|
|
||
|
channel->flags |= DMA_CHANNEL_FLAG_IN_USE;
|
||
|
devAttr->flags |= DMA_DEVICE_FLAG_IN_USE;
|
||
|
|
||
|
#if (DMA_DEBUG_TRACK_RESERVATION)
|
||
|
channel->fileName = fileName;
|
||
|
channel->lineNum = lineNum;
|
||
|
#endif
|
||
|
handle =
|
||
|
MAKE_HANDLE(devAttr->dedicatedController,
|
||
|
devAttr->dedicatedChannel);
|
||
|
goto out;
|
||
|
}
|
||
|
|
||
|
/* This device needs to use one of the shared channels. */
|
||
|
|
||
|
handle = DMA_INVALID_HANDLE;
|
||
|
while (handle == DMA_INVALID_HANDLE) {
|
||
|
/* Scan through the shared channels and see if one is available */
|
||
|
|
||
|
for (controllerIdx2 = 0; controllerIdx2 < DMA_NUM_CONTROLLERS;
|
||
|
controllerIdx2++) {
|
||
|
/* Check to see if we should try on controller 1 first. */
|
||
|
|
||
|
controllerIdx = controllerIdx2;
|
||
|
if ((devAttr->
|
||
|
flags & DMA_DEVICE_FLAG_ALLOC_DMA1_FIRST) != 0) {
|
||
|
controllerIdx = 1 - controllerIdx;
|
||
|
}
|
||
|
|
||
|
/* See if the device is available on the controller being tested */
|
||
|
|
||
|
if ((devAttr->
|
||
|
flags & (DMA_DEVICE_FLAG_ON_DMA0 << controllerIdx))
|
||
|
!= 0) {
|
||
|
for (channelIdx = 0;
|
||
|
channelIdx < DMA_NUM_CHANNELS;
|
||
|
channelIdx++) {
|
||
|
channel =
|
||
|
&gDMA.controller[controllerIdx].
|
||
|
channel[channelIdx];
|
||
|
|
||
|
if (((channel->
|
||
|
flags &
|
||
|
DMA_CHANNEL_FLAG_IS_DEDICATED) ==
|
||
|
0)
|
||
|
&&
|
||
|
((channel->
|
||
|
flags & DMA_CHANNEL_FLAG_IN_USE)
|
||
|
== 0)) {
|
||
|
if (((channel->
|
||
|
flags &
|
||
|
DMA_CHANNEL_FLAG_LARGE_FIFO)
|
||
|
!= 0)
|
||
|
&&
|
||
|
((devAttr->
|
||
|
flags &
|
||
|
DMA_DEVICE_FLAG_ALLOW_LARGE_FIFO)
|
||
|
== 0)) {
|
||
|
/* This channel is a large fifo - don't tie it up */
|
||
|
/* with devices that we don't want using it. */
|
||
|
|
||
|
continue;
|
||
|
}
|
||
|
|
||
|
channel->flags |=
|
||
|
DMA_CHANNEL_FLAG_IN_USE;
|
||
|
channel->devType = dev;
|
||
|
devAttr->flags |=
|
||
|
DMA_DEVICE_FLAG_IN_USE;
|
||
|
|
||
|
#if (DMA_DEBUG_TRACK_RESERVATION)
|
||
|
channel->fileName = fileName;
|
||
|
channel->lineNum = lineNum;
|
||
|
#endif
|
||
|
handle =
|
||
|
MAKE_HANDLE(controllerIdx,
|
||
|
channelIdx);
|
||
|
|
||
|
/* Now that we've reserved the channel - we can go ahead and configure it */
|
||
|
|
||
|
if (ConfigChannel(handle) != 0) {
|
||
|
handle = -EIO;
|
||
|
printk(KERN_ERR
|
||
|
"dma_request_channel: ConfigChannel failed\n");
|
||
|
}
|
||
|
goto out;
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
|
||
|
/* No channels are currently available. Let's wait for one to free up. */
|
||
|
|
||
|
{
|
||
|
DEFINE_WAIT(wait);
|
||
|
|
||
|
prepare_to_wait(&gDMA.freeChannelQ, &wait,
|
||
|
TASK_INTERRUPTIBLE);
|
||
|
up(&gDMA.lock);
|
||
|
schedule();
|
||
|
finish_wait(&gDMA.freeChannelQ, &wait);
|
||
|
|
||
|
if (signal_pending(current)) {
|
||
|
/* We don't currently hold gDMA.lock, so we return directly */
|
||
|
|
||
|
return -ERESTARTSYS;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
if (down_interruptible(&gDMA.lock)) {
|
||
|
return -ERESTARTSYS;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
out:
|
||
|
up(&gDMA.lock);
|
||
|
|
||
|
return handle;
|
||
|
}
|
||
|
|
||
|
/* Create both _dbg and non _dbg functions for modules. */
|
||
|
|
||
|
#if (DMA_DEBUG_TRACK_RESERVATION)
|
||
|
#undef dma_request_channel
|
||
|
DMA_Handle_t dma_request_channel(DMA_Device_t dev)
|
||
|
{
|
||
|
return dma_request_channel_dbg(dev, __FILE__, __LINE__);
|
||
|
}
|
||
|
|
||
|
EXPORT_SYMBOL(dma_request_channel_dbg);
|
||
|
#endif
|
||
|
EXPORT_SYMBOL(dma_request_channel);
|
||
|
|
||
|
/****************************************************************************/
|
||
|
/**
|
||
|
* Frees a previously allocated DMA Handle.
|
||
|
*/
|
||
|
/****************************************************************************/
|
||
|
|
||
|
int dma_free_channel(DMA_Handle_t handle /* DMA handle. */
|
||
|
) {
|
||
|
int rc = 0;
|
||
|
DMA_Channel_t *channel;
|
||
|
DMA_DeviceAttribute_t *devAttr;
|
||
|
|
||
|
if (down_interruptible(&gDMA.lock) < 0) {
|
||
|
return -ERESTARTSYS;
|
||
|
}
|
||
|
|
||
|
channel = HandleToChannel(handle);
|
||
|
if (channel == NULL) {
|
||
|
rc = -EINVAL;
|
||
|
goto out;
|
||
|
}
|
||
|
|
||
|
devAttr = &DMA_gDeviceAttribute[channel->devType];
|
||
|
|
||
|
if ((channel->flags & DMA_CHANNEL_FLAG_IS_DEDICATED) == 0) {
|
||
|
channel->lastDevType = channel->devType;
|
||
|
channel->devType = DMA_DEVICE_NONE;
|
||
|
}
|
||
|
channel->flags &= ~DMA_CHANNEL_FLAG_IN_USE;
|
||
|
devAttr->flags &= ~DMA_DEVICE_FLAG_IN_USE;
|
||
|
|
||
|
out:
|
||
|
up(&gDMA.lock);
|
||
|
|
||
|
wake_up_interruptible(&gDMA.freeChannelQ);
|
||
|
|
||
|
return rc;
|
||
|
}
|
||
|
|
||
|
EXPORT_SYMBOL(dma_free_channel);
|
||
|
|
||
|
/****************************************************************************/
|
||
|
/**
|
||
|
* Determines if a given device has been configured as using a shared
|
||
|
* channel.
|
||
|
*
|
||
|
* @return
|
||
|
* 0 Device uses a dedicated channel
|
||
|
* > zero Device uses a shared channel
|
||
|
* < zero Error code
|
||
|
*/
|
||
|
/****************************************************************************/
|
||
|
|
||
|
int dma_device_is_channel_shared(DMA_Device_t device /* Device to check. */
|
||
|
) {
|
||
|
DMA_DeviceAttribute_t *devAttr;
|
||
|
|
||
|
if (!IsDeviceValid(device)) {
|
||
|
return -ENODEV;
|
||
|
}
|
||
|
devAttr = &DMA_gDeviceAttribute[device];
|
||
|
|
||
|
return ((devAttr->flags & DMA_DEVICE_FLAG_IS_DEDICATED) == 0);
|
||
|
}
|
||
|
|
||
|
EXPORT_SYMBOL(dma_device_is_channel_shared);
|
||
|
|
||
|
/****************************************************************************/
|
||
|
/**
|
||
|
* Allocates buffers for the descriptors. This is normally done automatically
|
||
|
* but needs to be done explicitly when initiating a dma from interrupt
|
||
|
* context.
|
||
|
*
|
||
|
* @return
|
||
|
* 0 Descriptors were allocated successfully
|
||
|
* -EINVAL Invalid device type for this kind of transfer
|
||
|
* (i.e. the device is _MEM_TO_DEV and not _DEV_TO_MEM)
|
||
|
* -ENOMEM Memory exhausted
|
||
|
*/
|
||
|
/****************************************************************************/
|
||
|
|
||
|
int dma_alloc_descriptors(DMA_Handle_t handle, /* DMA Handle */
|
||
|
dmacHw_TRANSFER_TYPE_e transferType, /* Type of transfer being performed */
|
||
|
dma_addr_t srcData, /* Place to get data to write to device */
|
||
|
dma_addr_t dstData, /* Pointer to device data address */
|
||
|
size_t numBytes /* Number of bytes to transfer to the device */
|
||
|
) {
|
||
|
DMA_Channel_t *channel;
|
||
|
DMA_DeviceAttribute_t *devAttr;
|
||
|
int numDescriptors;
|
||
|
size_t ringBytesRequired;
|
||
|
int rc = 0;
|
||
|
|
||
|
channel = HandleToChannel(handle);
|
||
|
if (channel == NULL) {
|
||
|
return -ENODEV;
|
||
|
}
|
||
|
|
||
|
devAttr = &DMA_gDeviceAttribute[channel->devType];
|
||
|
|
||
|
if (devAttr->config.transferType != transferType) {
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
|
||
|
/* Figure out how many descriptors we need. */
|
||
|
|
||
|
/* printk("srcData: 0x%08x dstData: 0x%08x, numBytes: %d\n", */
|
||
|
/* srcData, dstData, numBytes); */
|
||
|
|
||
|
numDescriptors = dmacHw_calculateDescriptorCount(&devAttr->config,
|
||
|
(void *)srcData,
|
||
|
(void *)dstData,
|
||
|
numBytes);
|
||
|
if (numDescriptors < 0) {
|
||
|
printk(KERN_ERR "%s: dmacHw_calculateDescriptorCount failed\n",
|
||
|
__func__);
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
|
||
|
/* Check to see if we can reuse the existing descriptor ring, or if we need to allocate */
|
||
|
/* a new one. */
|
||
|
|
||
|
ringBytesRequired = dmacHw_descriptorLen(numDescriptors);
|
||
|
|
||
|
/* printk("ringBytesRequired: %d\n", ringBytesRequired); */
|
||
|
|
||
|
if (ringBytesRequired > devAttr->ring.bytesAllocated) {
|
||
|
/* Make sure that this code path is never taken from interrupt context. */
|
||
|
/* It's OK for an interrupt to initiate a DMA transfer, but the descriptor */
|
||
|
/* allocation needs to have already been done. */
|
||
|
|
||
|
might_sleep();
|
||
|
|
||
|
/* Free the old descriptor ring and allocate a new one. */
|
||
|
|
||
|
dma_free_descriptor_ring(&devAttr->ring);
|
||
|
|
||
|
/* And allocate a new one. */
|
||
|
|
||
|
rc =
|
||
|
dma_alloc_descriptor_ring(&devAttr->ring,
|
||
|
numDescriptors);
|
||
|
if (rc < 0) {
|
||
|
printk(KERN_ERR
|
||
|
"%s: dma_alloc_descriptor_ring(%d) failed\n",
|
||
|
__func__, numDescriptors);
|
||
|
return rc;
|
||
|
}
|
||
|
/* Setup the descriptor for this transfer */
|
||
|
|
||
|
if (dmacHw_initDescriptor(devAttr->ring.virtAddr,
|
||
|
devAttr->ring.physAddr,
|
||
|
devAttr->ring.bytesAllocated,
|
||
|
numDescriptors) < 0) {
|
||
|
printk(KERN_ERR "%s: dmacHw_initDescriptor failed\n",
|
||
|
__func__);
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
} else {
|
||
|
/* We've already got enough ring buffer allocated. All we need to do is reset */
|
||
|
/* any control information, just in case the previous DMA was stopped. */
|
||
|
|
||
|
dmacHw_resetDescriptorControl(devAttr->ring.virtAddr);
|
||
|
}
|
||
|
|
||
|
/* dma_alloc/free both set the prevSrc/DstData to 0. If they happen to be the same */
|
||
|
/* as last time, then we don't need to call setDataDescriptor again. */
|
||
|
|
||
|
if (dmacHw_setDataDescriptor(&devAttr->config,
|
||
|
devAttr->ring.virtAddr,
|
||
|
(void *)srcData,
|
||
|
(void *)dstData, numBytes) < 0) {
|
||
|
printk(KERN_ERR "%s: dmacHw_setDataDescriptor failed\n",
|
||
|
__func__);
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
|
||
|
/* Remember the critical information for this transfer so that we can eliminate */
|
||
|
/* another call to dma_alloc_descriptors if the caller reuses the same buffers */
|
||
|
|
||
|
devAttr->prevSrcData = srcData;
|
||
|
devAttr->prevDstData = dstData;
|
||
|
devAttr->prevNumBytes = numBytes;
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
EXPORT_SYMBOL(dma_alloc_descriptors);
|
||
|
|
||
|
/****************************************************************************/
|
||
|
/**
|
||
|
* Allocates and sets up descriptors for a double buffered circular buffer.
|
||
|
*
|
||
|
* This is primarily intended to be used for things like the ingress samples
|
||
|
* from a microphone.
|
||
|
*
|
||
|
* @return
|
||
|
* > 0 Number of descriptors actually allocated.
|
||
|
* -EINVAL Invalid device type for this kind of transfer
|
||
|
* (i.e. the device is _MEM_TO_DEV and not _DEV_TO_MEM)
|
||
|
* -ENOMEM Memory exhausted
|
||
|
*/
|
||
|
/****************************************************************************/
|
||
|
|
||
|
int dma_alloc_double_dst_descriptors(DMA_Handle_t handle, /* DMA Handle */
|
||
|
dma_addr_t srcData, /* Physical address of source data */
|
||
|
dma_addr_t dstData1, /* Physical address of first destination buffer */
|
||
|
dma_addr_t dstData2, /* Physical address of second destination buffer */
|
||
|
size_t numBytes /* Number of bytes in each destination buffer */
|
||
|
) {
|
||
|
DMA_Channel_t *channel;
|
||
|
DMA_DeviceAttribute_t *devAttr;
|
||
|
int numDst1Descriptors;
|
||
|
int numDst2Descriptors;
|
||
|
int numDescriptors;
|
||
|
size_t ringBytesRequired;
|
||
|
int rc = 0;
|
||
|
|
||
|
channel = HandleToChannel(handle);
|
||
|
if (channel == NULL) {
|
||
|
return -ENODEV;
|
||
|
}
|
||
|
|
||
|
devAttr = &DMA_gDeviceAttribute[channel->devType];
|
||
|
|
||
|
/* Figure out how many descriptors we need. */
|
||
|
|
||
|
/* printk("srcData: 0x%08x dstData: 0x%08x, numBytes: %d\n", */
|
||
|
/* srcData, dstData, numBytes); */
|
||
|
|
||
|
numDst1Descriptors =
|
||
|
dmacHw_calculateDescriptorCount(&devAttr->config, (void *)srcData,
|
||
|
(void *)dstData1, numBytes);
|
||
|
if (numDst1Descriptors < 0) {
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
numDst2Descriptors =
|
||
|
dmacHw_calculateDescriptorCount(&devAttr->config, (void *)srcData,
|
||
|
(void *)dstData2, numBytes);
|
||
|
if (numDst2Descriptors < 0) {
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
numDescriptors = numDst1Descriptors + numDst2Descriptors;
|
||
|
/* printk("numDescriptors: %d\n", numDescriptors); */
|
||
|
|
||
|
/* Check to see if we can reuse the existing descriptor ring, or if we need to allocate */
|
||
|
/* a new one. */
|
||
|
|
||
|
ringBytesRequired = dmacHw_descriptorLen(numDescriptors);
|
||
|
|
||
|
/* printk("ringBytesRequired: %d\n", ringBytesRequired); */
|
||
|
|
||
|
if (ringBytesRequired > devAttr->ring.bytesAllocated) {
|
||
|
/* Make sure that this code path is never taken from interrupt context. */
|
||
|
/* It's OK for an interrupt to initiate a DMA transfer, but the descriptor */
|
||
|
/* allocation needs to have already been done. */
|
||
|
|
||
|
might_sleep();
|
||
|
|
||
|
/* Free the old descriptor ring and allocate a new one. */
|
||
|
|
||
|
dma_free_descriptor_ring(&devAttr->ring);
|
||
|
|
||
|
/* And allocate a new one. */
|
||
|
|
||
|
rc =
|
||
|
dma_alloc_descriptor_ring(&devAttr->ring,
|
||
|
numDescriptors);
|
||
|
if (rc < 0) {
|
||
|
printk(KERN_ERR
|
||
|
"%s: dma_alloc_descriptor_ring(%d) failed\n",
|
||
|
__func__, ringBytesRequired);
|
||
|
return rc;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
/* Setup the descriptor for this transfer. Since this function is used with */
|
||
|
/* CONTINUOUS DMA operations, we need to reinitialize every time, otherwise */
|
||
|
/* setDataDescriptor will keep trying to append onto the end. */
|
||
|
|
||
|
if (dmacHw_initDescriptor(devAttr->ring.virtAddr,
|
||
|
devAttr->ring.physAddr,
|
||
|
devAttr->ring.bytesAllocated,
|
||
|
numDescriptors) < 0) {
|
||
|
printk(KERN_ERR "%s: dmacHw_initDescriptor failed\n", __func__);
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
|
||
|
/* dma_alloc/free both set the prevSrc/DstData to 0. If they happen to be the same */
|
||
|
/* as last time, then we don't need to call setDataDescriptor again. */
|
||
|
|
||
|
if (dmacHw_setDataDescriptor(&devAttr->config,
|
||
|
devAttr->ring.virtAddr,
|
||
|
(void *)srcData,
|
||
|
(void *)dstData1, numBytes) < 0) {
|
||
|
printk(KERN_ERR "%s: dmacHw_setDataDescriptor 1 failed\n",
|
||
|
__func__);
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
if (dmacHw_setDataDescriptor(&devAttr->config,
|
||
|
devAttr->ring.virtAddr,
|
||
|
(void *)srcData,
|
||
|
(void *)dstData2, numBytes) < 0) {
|
||
|
printk(KERN_ERR "%s: dmacHw_setDataDescriptor 2 failed\n",
|
||
|
__func__);
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
|
||
|
/* You should use dma_start_transfer rather than dma_transfer_xxx so we don't */
|
||
|
/* try to make the 'prev' variables right. */
|
||
|
|
||
|
devAttr->prevSrcData = 0;
|
||
|
devAttr->prevDstData = 0;
|
||
|
devAttr->prevNumBytes = 0;
|
||
|
|
||
|
return numDescriptors;
|
||
|
}
|
||
|
|
||
|
EXPORT_SYMBOL(dma_alloc_double_dst_descriptors);
|
||
|
|
||
|
/****************************************************************************/
|
||
|
/**
|
||
|
* Initiates a transfer when the descriptors have already been setup.
|
||
|
*
|
||
|
* This is a special case, and normally, the dma_transfer_xxx functions should
|
||
|
* be used.
|
||
|
*
|
||
|
* @return
|
||
|
* 0 Transfer was started successfully
|
||
|
* -ENODEV Invalid handle
|
||
|
*/
|
||
|
/****************************************************************************/
|
||
|
|
||
|
int dma_start_transfer(DMA_Handle_t handle)
|
||
|
{
|
||
|
DMA_Channel_t *channel;
|
||
|
DMA_DeviceAttribute_t *devAttr;
|
||
|
|
||
|
channel = HandleToChannel(handle);
|
||
|
if (channel == NULL) {
|
||
|
return -ENODEV;
|
||
|
}
|
||
|
devAttr = &DMA_gDeviceAttribute[channel->devType];
|
||
|
|
||
|
dmacHw_initiateTransfer(channel->dmacHwHandle, &devAttr->config,
|
||
|
devAttr->ring.virtAddr);
|
||
|
|
||
|
/* Since we got this far, everything went successfully */
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
EXPORT_SYMBOL(dma_start_transfer);
|
||
|
|
||
|
/****************************************************************************/
|
||
|
/**
|
||
|
* Stops a previously started DMA transfer.
|
||
|
*
|
||
|
* @return
|
||
|
* 0 Transfer was stopped successfully
|
||
|
* -ENODEV Invalid handle
|
||
|
*/
|
||
|
/****************************************************************************/
|
||
|
|
||
|
int dma_stop_transfer(DMA_Handle_t handle)
|
||
|
{
|
||
|
DMA_Channel_t *channel;
|
||
|
|
||
|
channel = HandleToChannel(handle);
|
||
|
if (channel == NULL) {
|
||
|
return -ENODEV;
|
||
|
}
|
||
|
|
||
|
dmacHw_stopTransfer(channel->dmacHwHandle);
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
EXPORT_SYMBOL(dma_stop_transfer);
|
||
|
|
||
|
/****************************************************************************/
|
||
|
/**
|
||
|
* Waits for a DMA to complete by polling. This function is only intended
|
||
|
* to be used for testing. Interrupts should be used for most DMA operations.
|
||
|
*/
|
||
|
/****************************************************************************/
|
||
|
|
||
|
int dma_wait_transfer_done(DMA_Handle_t handle)
|
||
|
{
|
||
|
DMA_Channel_t *channel;
|
||
|
dmacHw_TRANSFER_STATUS_e status;
|
||
|
|
||
|
channel = HandleToChannel(handle);
|
||
|
if (channel == NULL) {
|
||
|
return -ENODEV;
|
||
|
}
|
||
|
|
||
|
while ((status =
|
||
|
dmacHw_transferCompleted(channel->dmacHwHandle)) ==
|
||
|
dmacHw_TRANSFER_STATUS_BUSY) {
|
||
|
;
|
||
|
}
|
||
|
|
||
|
if (status == dmacHw_TRANSFER_STATUS_ERROR) {
|
||
|
printk(KERN_ERR "%s: DMA transfer failed\n", __func__);
|
||
|
return -EIO;
|
||
|
}
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
EXPORT_SYMBOL(dma_wait_transfer_done);
|
||
|
|
||
|
/****************************************************************************/
|
||
|
/**
|
||
|
* Initiates a DMA, allocating the descriptors as required.
|
||
|
*
|
||
|
* @return
|
||
|
* 0 Transfer was started successfully
|
||
|
* -EINVAL Invalid device type for this kind of transfer
|
||
|
* (i.e. the device is _DEV_TO_MEM and not _MEM_TO_DEV)
|
||
|
*/
|
||
|
/****************************************************************************/
|
||
|
|
||
|
int dma_transfer(DMA_Handle_t handle, /* DMA Handle */
|
||
|
dmacHw_TRANSFER_TYPE_e transferType, /* Type of transfer being performed */
|
||
|
dma_addr_t srcData, /* Place to get data to write to device */
|
||
|
dma_addr_t dstData, /* Pointer to device data address */
|
||
|
size_t numBytes /* Number of bytes to transfer to the device */
|
||
|
) {
|
||
|
DMA_Channel_t *channel;
|
||
|
DMA_DeviceAttribute_t *devAttr;
|
||
|
int rc = 0;
|
||
|
|
||
|
channel = HandleToChannel(handle);
|
||
|
if (channel == NULL) {
|
||
|
return -ENODEV;
|
||
|
}
|
||
|
|
||
|
devAttr = &DMA_gDeviceAttribute[channel->devType];
|
||
|
|
||
|
if (devAttr->config.transferType != transferType) {
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
|
||
|
/* We keep track of the information about the previous request for this */
|
||
|
/* device, and if the attributes match, then we can use the descriptors we setup */
|
||
|
/* the last time, and not have to reinitialize everything. */
|
||
|
|
||
|
{
|
||
|
rc =
|
||
|
dma_alloc_descriptors(handle, transferType, srcData,
|
||
|
dstData, numBytes);
|
||
|
if (rc != 0) {
|
||
|
return rc;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
/* And kick off the transfer */
|
||
|
|
||
|
devAttr->numBytes = numBytes;
|
||
|
devAttr->transferStartTime = timer_get_tick_count();
|
||
|
|
||
|
dmacHw_initiateTransfer(channel->dmacHwHandle, &devAttr->config,
|
||
|
devAttr->ring.virtAddr);
|
||
|
|
||
|
/* Since we got this far, everything went successfully */
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
EXPORT_SYMBOL(dma_transfer);
|
||
|
|
||
|
/****************************************************************************/
|
||
|
/**
|
||
|
* Set the callback function which will be called when a transfer completes.
|
||
|
* If a NULL callback function is set, then no callback will occur.
|
||
|
*
|
||
|
* @note @a devHandler will be called from IRQ context.
|
||
|
*
|
||
|
* @return
|
||
|
* 0 - Success
|
||
|
* -ENODEV - Device handed in is invalid.
|
||
|
*/
|
||
|
/****************************************************************************/
|
||
|
|
||
|
int dma_set_device_handler(DMA_Device_t dev, /* Device to set the callback for. */
|
||
|
DMA_DeviceHandler_t devHandler, /* Function to call when the DMA completes */
|
||
|
void *userData /* Pointer which will be passed to devHandler. */
|
||
|
) {
|
||
|
DMA_DeviceAttribute_t *devAttr;
|
||
|
unsigned long flags;
|
||
|
|
||
|
if (!IsDeviceValid(dev)) {
|
||
|
return -ENODEV;
|
||
|
}
|
||
|
devAttr = &DMA_gDeviceAttribute[dev];
|
||
|
|
||
|
local_irq_save(flags);
|
||
|
|
||
|
devAttr->userData = userData;
|
||
|
devAttr->devHandler = devHandler;
|
||
|
|
||
|
local_irq_restore(flags);
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
EXPORT_SYMBOL(dma_set_device_handler);
|
||
|
|
||
|
/****************************************************************************/
|
||
|
/**
|
||
|
* Initializes a memory mapping structure
|
||
|
*/
|
||
|
/****************************************************************************/
|
||
|
|
||
|
int dma_init_mem_map(DMA_MemMap_t *memMap)
|
||
|
{
|
||
|
memset(memMap, 0, sizeof(*memMap));
|
||
|
|
||
|
init_MUTEX(&memMap->lock);
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
EXPORT_SYMBOL(dma_init_mem_map);
|
||
|
|
||
|
/****************************************************************************/
|
||
|
/**
|
||
|
* Releases any memory currently being held by a memory mapping structure.
|
||
|
*/
|
||
|
/****************************************************************************/
|
||
|
|
||
|
int dma_term_mem_map(DMA_MemMap_t *memMap)
|
||
|
{
|
||
|
down(&memMap->lock); /* Just being paranoid */
|
||
|
|
||
|
/* Free up any allocated memory */
|
||
|
|
||
|
up(&memMap->lock);
|
||
|
memset(memMap, 0, sizeof(*memMap));
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
EXPORT_SYMBOL(dma_term_mem_map);
|
||
|
|
||
|
/****************************************************************************/
|
||
|
/**
|
||
|
* Looks at a memory address and categorizes it.
|
||
|
*
|
||
|
* @return One of the values from the DMA_MemType_t enumeration.
|
||
|
*/
|
||
|
/****************************************************************************/
|
||
|
|
||
|
DMA_MemType_t dma_mem_type(void *addr)
|
||
|
{
|
||
|
unsigned long addrVal = (unsigned long)addr;
|
||
|
|
||
|
if (addrVal >= VMALLOC_END) {
|
||
|
/* NOTE: DMA virtual memory space starts at 0xFFxxxxxx */
|
||
|
|
||
|
/* dma_alloc_xxx pages are physically and virtually contiguous */
|
||
|
|
||
|
return DMA_MEM_TYPE_DMA;
|
||
|
}
|
||
|
|
||
|
/* Technically, we could add one more classification. Addresses between VMALLOC_END */
|
||
|
/* and the beginning of the DMA virtual address could be considered to be I/O space. */
|
||
|
/* Right now, nobody cares about this particular classification, so we ignore it. */
|
||
|
|
||
|
if (is_vmalloc_addr(addr)) {
|
||
|
/* Address comes from the vmalloc'd region. Pages are virtually */
|
||
|
/* contiguous but NOT physically contiguous */
|
||
|
|
||
|
return DMA_MEM_TYPE_VMALLOC;
|
||
|
}
|
||
|
|
||
|
if (addrVal >= PAGE_OFFSET) {
|
||
|
/* PAGE_OFFSET is typically 0xC0000000 */
|
||
|
|
||
|
/* kmalloc'd pages are physically contiguous */
|
||
|
|
||
|
return DMA_MEM_TYPE_KMALLOC;
|
||
|
}
|
||
|
|
||
|
return DMA_MEM_TYPE_USER;
|
||
|
}
|
||
|
|
||
|
EXPORT_SYMBOL(dma_mem_type);
|
||
|
|
||
|
/****************************************************************************/
|
||
|
/**
|
||
|
* Looks at a memory address and determines if we support DMA'ing to/from
|
||
|
* that type of memory.
|
||
|
*
|
||
|
* @return boolean -
|
||
|
* return value != 0 means dma supported
|
||
|
* return value == 0 means dma not supported
|
||
|
*/
|
||
|
/****************************************************************************/
|
||
|
|
||
|
int dma_mem_supports_dma(void *addr)
|
||
|
{
|
||
|
DMA_MemType_t memType = dma_mem_type(addr);
|
||
|
|
||
|
return (memType == DMA_MEM_TYPE_DMA)
|
||
|
#if ALLOW_MAP_OF_KMALLOC_MEMORY
|
||
|
|| (memType == DMA_MEM_TYPE_KMALLOC)
|
||
|
#endif
|
||
|
|| (memType == DMA_MEM_TYPE_USER);
|
||
|
}
|
||
|
|
||
|
EXPORT_SYMBOL(dma_mem_supports_dma);
|
||
|
|
||
|
/****************************************************************************/
|
||
|
/**
|
||
|
* Maps in a memory region such that it can be used for performing a DMA.
|
||
|
*
|
||
|
* @return
|
||
|
*/
|
||
|
/****************************************************************************/
|
||
|
|
||
|
int dma_map_start(DMA_MemMap_t *memMap, /* Stores state information about the map */
|
||
|
enum dma_data_direction dir /* Direction that the mapping will be going */
|
||
|
) {
|
||
|
int rc;
|
||
|
|
||
|
down(&memMap->lock);
|
||
|
|
||
|
DMA_MAP_PRINT("memMap: %p\n", memMap);
|
||
|
|
||
|
if (memMap->inUse) {
|
||
|
printk(KERN_ERR "%s: memory map %p is already being used\n",
|
||
|
__func__, memMap);
|
||
|
rc = -EBUSY;
|
||
|
goto out;
|
||
|
}
|
||
|
|
||
|
memMap->inUse = 1;
|
||
|
memMap->dir = dir;
|
||
|
memMap->numRegionsUsed = 0;
|
||
|
|
||
|
rc = 0;
|
||
|
|
||
|
out:
|
||
|
|
||
|
DMA_MAP_PRINT("returning %d", rc);
|
||
|
|
||
|
up(&memMap->lock);
|
||
|
|
||
|
return rc;
|
||
|
}
|
||
|
|
||
|
EXPORT_SYMBOL(dma_map_start);
|
||
|
|
||
|
/****************************************************************************/
|
||
|
/**
|
||
|
* Adds a segment of memory to a memory map. Each segment is both
|
||
|
* physically and virtually contiguous.
|
||
|
*
|
||
|
* @return 0 on success, error code otherwise.
|
||
|
*/
|
||
|
/****************************************************************************/
|
||
|
|
||
|
static int dma_map_add_segment(DMA_MemMap_t *memMap, /* Stores state information about the map */
|
||
|
DMA_Region_t *region, /* Region that the segment belongs to */
|
||
|
void *virtAddr, /* Virtual address of the segment being added */
|
||
|
dma_addr_t physAddr, /* Physical address of the segment being added */
|
||
|
size_t numBytes /* Number of bytes of the segment being added */
|
||
|
) {
|
||
|
DMA_Segment_t *segment;
|
||
|
|
||
|
DMA_MAP_PRINT("memMap:%p va:%p pa:0x%x #:%d\n", memMap, virtAddr,
|
||
|
physAddr, numBytes);
|
||
|
|
||
|
/* Sanity check */
|
||
|
|
||
|
if (((unsigned long)virtAddr < (unsigned long)region->virtAddr)
|
||
|
|| (((unsigned long)virtAddr + numBytes)) >
|
||
|
((unsigned long)region->virtAddr + region->numBytes)) {
|
||
|
printk(KERN_ERR
|
||
|
"%s: virtAddr %p is outside region @ %p len: %d\n",
|
||
|
__func__, virtAddr, region->virtAddr, region->numBytes);
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
|
||
|
if (region->numSegmentsUsed > 0) {
|
||
|
/* Check to see if this segment is physically contiguous with the previous one */
|
||
|
|
||
|
segment = ®ion->segment[region->numSegmentsUsed - 1];
|
||
|
|
||
|
if ((segment->physAddr + segment->numBytes) == physAddr) {
|
||
|
/* It is - just add on to the end */
|
||
|
|
||
|
DMA_MAP_PRINT("appending %d bytes to last segment\n",
|
||
|
numBytes);
|
||
|
|
||
|
segment->numBytes += numBytes;
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
/* Reallocate to hold more segments, if required. */
|
||
|
|
||
|
if (region->numSegmentsUsed >= region->numSegmentsAllocated) {
|
||
|
DMA_Segment_t *newSegment;
|
||
|
size_t oldSize =
|
||
|
region->numSegmentsAllocated * sizeof(*newSegment);
|
||
|
int newAlloc = region->numSegmentsAllocated + 4;
|
||
|
size_t newSize = newAlloc * sizeof(*newSegment);
|
||
|
|
||
|
newSegment = kmalloc(newSize, GFP_KERNEL);
|
||
|
if (newSegment == NULL) {
|
||
|
return -ENOMEM;
|
||
|
}
|
||
|
memcpy(newSegment, region->segment, oldSize);
|
||
|
memset(&((uint8_t *) newSegment)[oldSize], 0,
|
||
|
newSize - oldSize);
|
||
|
kfree(region->segment);
|
||
|
|
||
|
region->numSegmentsAllocated = newAlloc;
|
||
|
region->segment = newSegment;
|
||
|
}
|
||
|
|
||
|
segment = ®ion->segment[region->numSegmentsUsed];
|
||
|
region->numSegmentsUsed++;
|
||
|
|
||
|
segment->virtAddr = virtAddr;
|
||
|
segment->physAddr = physAddr;
|
||
|
segment->numBytes = numBytes;
|
||
|
|
||
|
DMA_MAP_PRINT("returning success\n");
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
/****************************************************************************/
|
||
|
/**
|
||
|
* Adds a region of memory to a memory map. Each region is virtually
|
||
|
* contiguous, but not necessarily physically contiguous.
|
||
|
*
|
||
|
* @return 0 on success, error code otherwise.
|
||
|
*/
|
||
|
/****************************************************************************/
|
||
|
|
||
|
int dma_map_add_region(DMA_MemMap_t *memMap, /* Stores state information about the map */
|
||
|
void *mem, /* Virtual address that we want to get a map of */
|
||
|
size_t numBytes /* Number of bytes being mapped */
|
||
|
) {
|
||
|
unsigned long addr = (unsigned long)mem;
|
||
|
unsigned int offset;
|
||
|
int rc = 0;
|
||
|
DMA_Region_t *region;
|
||
|
dma_addr_t physAddr;
|
||
|
|
||
|
down(&memMap->lock);
|
||
|
|
||
|
DMA_MAP_PRINT("memMap:%p va:%p #:%d\n", memMap, mem, numBytes);
|
||
|
|
||
|
if (!memMap->inUse) {
|
||
|
printk(KERN_ERR "%s: Make sure you call dma_map_start first\n",
|
||
|
__func__);
|
||
|
rc = -EINVAL;
|
||
|
goto out;
|
||
|
}
|
||
|
|
||
|
/* Reallocate to hold more regions. */
|
||
|
|
||
|
if (memMap->numRegionsUsed >= memMap->numRegionsAllocated) {
|
||
|
DMA_Region_t *newRegion;
|
||
|
size_t oldSize =
|
||
|
memMap->numRegionsAllocated * sizeof(*newRegion);
|
||
|
int newAlloc = memMap->numRegionsAllocated + 4;
|
||
|
size_t newSize = newAlloc * sizeof(*newRegion);
|
||
|
|
||
|
newRegion = kmalloc(newSize, GFP_KERNEL);
|
||
|
if (newRegion == NULL) {
|
||
|
rc = -ENOMEM;
|
||
|
goto out;
|
||
|
}
|
||
|
memcpy(newRegion, memMap->region, oldSize);
|
||
|
memset(&((uint8_t *) newRegion)[oldSize], 0, newSize - oldSize);
|
||
|
|
||
|
kfree(memMap->region);
|
||
|
|
||
|
memMap->numRegionsAllocated = newAlloc;
|
||
|
memMap->region = newRegion;
|
||
|
}
|
||
|
|
||
|
region = &memMap->region[memMap->numRegionsUsed];
|
||
|
memMap->numRegionsUsed++;
|
||
|
|
||
|
offset = addr & ~PAGE_MASK;
|
||
|
|
||
|
region->memType = dma_mem_type(mem);
|
||
|
region->virtAddr = mem;
|
||
|
region->numBytes = numBytes;
|
||
|
region->numSegmentsUsed = 0;
|
||
|
region->numLockedPages = 0;
|
||
|
region->lockedPages = NULL;
|
||
|
|
||
|
switch (region->memType) {
|
||
|
case DMA_MEM_TYPE_VMALLOC:
|
||
|
{
|
||
|
atomic_inc(&gDmaStatMemTypeVmalloc);
|
||
|
|
||
|
/* printk(KERN_ERR "%s: vmalloc'd pages are not supported\n", __func__); */
|
||
|
|
||
|
/* vmalloc'd pages are not physically contiguous */
|
||
|
|
||
|
rc = -EINVAL;
|
||
|
break;
|
||
|
}
|
||
|
|
||
|
case DMA_MEM_TYPE_KMALLOC:
|
||
|
{
|
||
|
atomic_inc(&gDmaStatMemTypeKmalloc);
|
||
|
|
||
|
/* kmalloc'd pages are physically contiguous, so they'll have exactly */
|
||
|
/* one segment */
|
||
|
|
||
|
#if ALLOW_MAP_OF_KMALLOC_MEMORY
|
||
|
physAddr =
|
||
|
dma_map_single(NULL, mem, numBytes, memMap->dir);
|
||
|
rc = dma_map_add_segment(memMap, region, mem, physAddr,
|
||
|
numBytes);
|
||
|
#else
|
||
|
rc = -EINVAL;
|
||
|
#endif
|
||
|
break;
|
||
|
}
|
||
|
|
||
|
case DMA_MEM_TYPE_DMA:
|
||
|
{
|
||
|
/* dma_alloc_xxx pages are physically contiguous */
|
||
|
|
||
|
atomic_inc(&gDmaStatMemTypeCoherent);
|
||
|
|
||
|
physAddr = (vmalloc_to_pfn(mem) << PAGE_SHIFT) + offset;
|
||
|
|
||
|
dma_sync_single_for_cpu(NULL, physAddr, numBytes,
|
||
|
memMap->dir);
|
||
|
rc = dma_map_add_segment(memMap, region, mem, physAddr,
|
||
|
numBytes);
|
||
|
break;
|
||
|
}
|
||
|
|
||
|
case DMA_MEM_TYPE_USER:
|
||
|
{
|
||
|
size_t firstPageOffset;
|
||
|
size_t firstPageSize;
|
||
|
struct page **pages;
|
||
|
struct task_struct *userTask;
|
||
|
|
||
|
atomic_inc(&gDmaStatMemTypeUser);
|
||
|
|
||
|
#if 1
|
||
|
/* If the pages are user pages, then the dma_mem_map_set_user_task function */
|
||
|
/* must have been previously called. */
|
||
|
|
||
|
if (memMap->userTask == NULL) {
|
||
|
printk(KERN_ERR
|
||
|
"%s: must call dma_mem_map_set_user_task when using user-mode memory\n",
|
||
|
__func__);
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
|
||
|
/* User pages need to be locked. */
|
||
|
|
||
|
firstPageOffset =
|
||
|
(unsigned long)region->virtAddr & (PAGE_SIZE - 1);
|
||
|
firstPageSize = PAGE_SIZE - firstPageOffset;
|
||
|
|
||
|
region->numLockedPages = (firstPageOffset
|
||
|
+ region->numBytes +
|
||
|
PAGE_SIZE - 1) / PAGE_SIZE;
|
||
|
pages =
|
||
|
kmalloc(region->numLockedPages *
|
||
|
sizeof(struct page *), GFP_KERNEL);
|
||
|
|
||
|
if (pages == NULL) {
|
||
|
region->numLockedPages = 0;
|
||
|
return -ENOMEM;
|
||
|
}
|
||
|
|
||
|
userTask = memMap->userTask;
|
||
|
|
||
|
down_read(&userTask->mm->mmap_sem);
|
||
|
rc = get_user_pages(userTask, /* task */
|
||
|
userTask->mm, /* mm */
|
||
|
(unsigned long)region->virtAddr, /* start */
|
||
|
region->numLockedPages, /* len */
|
||
|
memMap->dir == DMA_FROM_DEVICE, /* write */
|
||
|
0, /* force */
|
||
|
pages, /* pages (array of pointers to page) */
|
||
|
NULL); /* vmas */
|
||
|
up_read(&userTask->mm->mmap_sem);
|
||
|
|
||
|
if (rc != region->numLockedPages) {
|
||
|
kfree(pages);
|
||
|
region->numLockedPages = 0;
|
||
|
|
||
|
if (rc >= 0) {
|
||
|
rc = -EINVAL;
|
||
|
}
|
||
|
} else {
|
||
|
uint8_t *virtAddr = region->virtAddr;
|
||
|
size_t bytesRemaining;
|
||
|
int pageIdx;
|
||
|
|
||
|
rc = 0; /* Since get_user_pages returns +ve number */
|
||
|
|
||
|
region->lockedPages = pages;
|
||
|
|
||
|
/* We've locked the user pages. Now we need to walk them and figure */
|
||
|
/* out the physical addresses. */
|
||
|
|
||
|
/* The first page may be partial */
|
||
|
|
||
|
dma_map_add_segment(memMap,
|
||
|
region,
|
||
|
virtAddr,
|
||
|
PFN_PHYS(page_to_pfn
|
||
|
(pages[0])) +
|
||
|
firstPageOffset,
|
||
|
firstPageSize);
|
||
|
|
||
|
virtAddr += firstPageSize;
|
||
|
bytesRemaining =
|
||
|
region->numBytes - firstPageSize;
|
||
|
|
||
|
for (pageIdx = 1;
|
||
|
pageIdx < region->numLockedPages;
|
||
|
pageIdx++) {
|
||
|
size_t bytesThisPage =
|
||
|
(bytesRemaining >
|
||
|
PAGE_SIZE ? PAGE_SIZE :
|
||
|
bytesRemaining);
|
||
|
|
||
|
DMA_MAP_PRINT
|
||
|
("pageIdx:%d pages[pageIdx]=%p pfn=%u phys=%u\n",
|
||
|
pageIdx, pages[pageIdx],
|
||
|
page_to_pfn(pages[pageIdx]),
|
||
|
PFN_PHYS(page_to_pfn
|
||
|
(pages[pageIdx])));
|
||
|
|
||
|
dma_map_add_segment(memMap,
|
||
|
region,
|
||
|
virtAddr,
|
||
|
PFN_PHYS(page_to_pfn
|
||
|
(pages
|
||
|
[pageIdx])),
|
||
|
bytesThisPage);
|
||
|
|
||
|
virtAddr += bytesThisPage;
|
||
|
bytesRemaining -= bytesThisPage;
|
||
|
}
|
||
|
}
|
||
|
#else
|
||
|
printk(KERN_ERR
|
||
|
"%s: User mode pages are not yet supported\n",
|
||
|
__func__);
|
||
|
|
||
|
/* user pages are not physically contiguous */
|
||
|
|
||
|
rc = -EINVAL;
|
||
|
#endif
|
||
|
break;
|
||
|
}
|
||
|
|
||
|
default:
|
||
|
{
|
||
|
printk(KERN_ERR "%s: Unsupported memory type: %d\n",
|
||
|
__func__, region->memType);
|
||
|
|
||
|
rc = -EINVAL;
|
||
|
break;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
if (rc != 0) {
|
||
|
memMap->numRegionsUsed--;
|
||
|
}
|
||
|
|
||
|
out:
|
||
|
|
||
|
DMA_MAP_PRINT("returning %d\n", rc);
|
||
|
|
||
|
up(&memMap->lock);
|
||
|
|
||
|
return rc;
|
||
|
}
|
||
|
|
||
|
EXPORT_SYMBOL(dma_map_add_segment);
|
||
|
|
||
|
/****************************************************************************/
|
||
|
/**
|
||
|
* Maps in a memory region such that it can be used for performing a DMA.
|
||
|
*
|
||
|
* @return 0 on success, error code otherwise.
|
||
|
*/
|
||
|
/****************************************************************************/
|
||
|
|
||
|
int dma_map_mem(DMA_MemMap_t *memMap, /* Stores state information about the map */
|
||
|
void *mem, /* Virtual address that we want to get a map of */
|
||
|
size_t numBytes, /* Number of bytes being mapped */
|
||
|
enum dma_data_direction dir /* Direction that the mapping will be going */
|
||
|
) {
|
||
|
int rc;
|
||
|
|
||
|
rc = dma_map_start(memMap, dir);
|
||
|
if (rc == 0) {
|
||
|
rc = dma_map_add_region(memMap, mem, numBytes);
|
||
|
if (rc < 0) {
|
||
|
/* Since the add fails, this function will fail, and the caller won't */
|
||
|
/* call unmap, so we need to do it here. */
|
||
|
|
||
|
dma_unmap(memMap, 0);
|
||
|
}
|
||
|
}
|
||
|
|
||
|
return rc;
|
||
|
}
|
||
|
|
||
|
EXPORT_SYMBOL(dma_map_mem);
|
||
|
|
||
|
/****************************************************************************/
|
||
|
/**
|
||
|
* Setup a descriptor ring for a given memory map.
|
||
|
*
|
||
|
* It is assumed that the descriptor ring has already been initialized, and
|
||
|
* this routine will only reallocate a new descriptor ring if the existing
|
||
|
* one is too small.
|
||
|
*
|
||
|
* @return 0 on success, error code otherwise.
|
||
|
*/
|
||
|
/****************************************************************************/
|
||
|
|
||
|
int dma_map_create_descriptor_ring(DMA_Device_t dev, /* DMA device (where the ring is stored) */
|
||
|
DMA_MemMap_t *memMap, /* Memory map that will be used */
|
||
|
dma_addr_t devPhysAddr /* Physical address of device */
|
||
|
) {
|
||
|
int rc;
|
||
|
int numDescriptors;
|
||
|
DMA_DeviceAttribute_t *devAttr;
|
||
|
DMA_Region_t *region;
|
||
|
DMA_Segment_t *segment;
|
||
|
dma_addr_t srcPhysAddr;
|
||
|
dma_addr_t dstPhysAddr;
|
||
|
int regionIdx;
|
||
|
int segmentIdx;
|
||
|
|
||
|
devAttr = &DMA_gDeviceAttribute[dev];
|
||
|
|
||
|
down(&memMap->lock);
|
||
|
|
||
|
/* Figure out how many descriptors we need */
|
||
|
|
||
|
numDescriptors = 0;
|
||
|
for (regionIdx = 0; regionIdx < memMap->numRegionsUsed; regionIdx++) {
|
||
|
region = &memMap->region[regionIdx];
|
||
|
|
||
|
for (segmentIdx = 0; segmentIdx < region->numSegmentsUsed;
|
||
|
segmentIdx++) {
|
||
|
segment = ®ion->segment[segmentIdx];
|
||
|
|
||
|
if (memMap->dir == DMA_TO_DEVICE) {
|
||
|
srcPhysAddr = segment->physAddr;
|
||
|
dstPhysAddr = devPhysAddr;
|
||
|
} else {
|
||
|
srcPhysAddr = devPhysAddr;
|
||
|
dstPhysAddr = segment->physAddr;
|
||
|
}
|
||
|
|
||
|
rc =
|
||
|
dma_calculate_descriptor_count(dev, srcPhysAddr,
|
||
|
dstPhysAddr,
|
||
|
segment->
|
||
|
numBytes);
|
||
|
if (rc < 0) {
|
||
|
printk(KERN_ERR
|
||
|
"%s: dma_calculate_descriptor_count failed: %d\n",
|
||
|
__func__, rc);
|
||
|
goto out;
|
||
|
}
|
||
|
numDescriptors += rc;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
/* Adjust the size of the ring, if it isn't big enough */
|
||
|
|
||
|
if (numDescriptors > devAttr->ring.descriptorsAllocated) {
|
||
|
dma_free_descriptor_ring(&devAttr->ring);
|
||
|
rc =
|
||
|
dma_alloc_descriptor_ring(&devAttr->ring,
|
||
|
numDescriptors);
|
||
|
if (rc < 0) {
|
||
|
printk(KERN_ERR
|
||
|
"%s: dma_alloc_descriptor_ring failed: %d\n",
|
||
|
__func__, rc);
|
||
|
goto out;
|
||
|
}
|
||
|
} else {
|
||
|
rc =
|
||
|
dma_init_descriptor_ring(&devAttr->ring,
|
||
|
numDescriptors);
|
||
|
if (rc < 0) {
|
||
|
printk(KERN_ERR
|
||
|
"%s: dma_init_descriptor_ring failed: %d\n",
|
||
|
__func__, rc);
|
||
|
goto out;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
/* Populate the descriptors */
|
||
|
|
||
|
for (regionIdx = 0; regionIdx < memMap->numRegionsUsed; regionIdx++) {
|
||
|
region = &memMap->region[regionIdx];
|
||
|
|
||
|
for (segmentIdx = 0; segmentIdx < region->numSegmentsUsed;
|
||
|
segmentIdx++) {
|
||
|
segment = ®ion->segment[segmentIdx];
|
||
|
|
||
|
if (memMap->dir == DMA_TO_DEVICE) {
|
||
|
srcPhysAddr = segment->physAddr;
|
||
|
dstPhysAddr = devPhysAddr;
|
||
|
} else {
|
||
|
srcPhysAddr = devPhysAddr;
|
||
|
dstPhysAddr = segment->physAddr;
|
||
|
}
|
||
|
|
||
|
rc =
|
||
|
dma_add_descriptors(&devAttr->ring, dev,
|
||
|
srcPhysAddr, dstPhysAddr,
|
||
|
segment->numBytes);
|
||
|
if (rc < 0) {
|
||
|
printk(KERN_ERR
|
||
|
"%s: dma_add_descriptors failed: %d\n",
|
||
|
__func__, rc);
|
||
|
goto out;
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
|
||
|
rc = 0;
|
||
|
|
||
|
out:
|
||
|
|
||
|
up(&memMap->lock);
|
||
|
return rc;
|
||
|
}
|
||
|
|
||
|
EXPORT_SYMBOL(dma_map_create_descriptor_ring);
|
||
|
|
||
|
/****************************************************************************/
|
||
|
/**
|
||
|
* Maps in a memory region such that it can be used for performing a DMA.
|
||
|
*
|
||
|
* @return
|
||
|
*/
|
||
|
/****************************************************************************/
|
||
|
|
||
|
int dma_unmap(DMA_MemMap_t *memMap, /* Stores state information about the map */
|
||
|
int dirtied /* non-zero if any of the pages were modified */
|
||
|
) {
|
||
|
int regionIdx;
|
||
|
int segmentIdx;
|
||
|
DMA_Region_t *region;
|
||
|
DMA_Segment_t *segment;
|
||
|
|
||
|
for (regionIdx = 0; regionIdx < memMap->numRegionsUsed; regionIdx++) {
|
||
|
region = &memMap->region[regionIdx];
|
||
|
|
||
|
for (segmentIdx = 0; segmentIdx < region->numSegmentsUsed;
|
||
|
segmentIdx++) {
|
||
|
segment = ®ion->segment[segmentIdx];
|
||
|
|
||
|
switch (region->memType) {
|
||
|
case DMA_MEM_TYPE_VMALLOC:
|
||
|
{
|
||
|
printk(KERN_ERR
|
||
|
"%s: vmalloc'd pages are not yet supported\n",
|
||
|
__func__);
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
|
||
|
case DMA_MEM_TYPE_KMALLOC:
|
||
|
{
|
||
|
#if ALLOW_MAP_OF_KMALLOC_MEMORY
|
||
|
dma_unmap_single(NULL,
|
||
|
segment->physAddr,
|
||
|
segment->numBytes,
|
||
|
memMap->dir);
|
||
|
#endif
|
||
|
break;
|
||
|
}
|
||
|
|
||
|
case DMA_MEM_TYPE_DMA:
|
||
|
{
|
||
|
dma_sync_single_for_cpu(NULL,
|
||
|
segment->
|
||
|
physAddr,
|
||
|
segment->
|
||
|
numBytes,
|
||
|
memMap->dir);
|
||
|
break;
|
||
|
}
|
||
|
|
||
|
case DMA_MEM_TYPE_USER:
|
||
|
{
|
||
|
/* Nothing to do here. */
|
||
|
|
||
|
break;
|
||
|
}
|
||
|
|
||
|
default:
|
||
|
{
|
||
|
printk(KERN_ERR
|
||
|
"%s: Unsupported memory type: %d\n",
|
||
|
__func__, region->memType);
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
segment->virtAddr = NULL;
|
||
|
segment->physAddr = 0;
|
||
|
segment->numBytes = 0;
|
||
|
}
|
||
|
|
||
|
if (region->numLockedPages > 0) {
|
||
|
int pageIdx;
|
||
|
|
||
|
/* Some user pages were locked. We need to go and unlock them now. */
|
||
|
|
||
|
for (pageIdx = 0; pageIdx < region->numLockedPages;
|
||
|
pageIdx++) {
|
||
|
struct page *page =
|
||
|
region->lockedPages[pageIdx];
|
||
|
|
||
|
if (memMap->dir == DMA_FROM_DEVICE) {
|
||
|
SetPageDirty(page);
|
||
|
}
|
||
|
page_cache_release(page);
|
||
|
}
|
||
|
kfree(region->lockedPages);
|
||
|
region->numLockedPages = 0;
|
||
|
region->lockedPages = NULL;
|
||
|
}
|
||
|
|
||
|
region->memType = DMA_MEM_TYPE_NONE;
|
||
|
region->virtAddr = NULL;
|
||
|
region->numBytes = 0;
|
||
|
region->numSegmentsUsed = 0;
|
||
|
}
|
||
|
memMap->userTask = NULL;
|
||
|
memMap->numRegionsUsed = 0;
|
||
|
memMap->inUse = 0;
|
||
|
|
||
|
up(&memMap->lock);
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
EXPORT_SYMBOL(dma_unmap);
|