![Alejandro Martinez Ruiz](/assets/img/avatar_default.png)
Signed-off-by: Alejandro Martinez Ruiz <alex@flawedcode.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
223 lines
5.1 KiB
C
223 lines
5.1 KiB
C
/*
|
|
* linux/arch/arm/kernel/dma-isa.c
|
|
*
|
|
* Copyright (C) 1999-2000 Russell King
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*
|
|
* ISA DMA primitives
|
|
* Taken from various sources, including:
|
|
* linux/include/asm/dma.h: Defines for using and allocating dma channels.
|
|
* Written by Hennus Bergman, 1992.
|
|
* High DMA channel support & info by Hannu Savolainen and John Boyd,
|
|
* Nov. 1992.
|
|
* arch/arm/kernel/dma-ebsa285.c
|
|
* Copyright (C) 1998 Phil Blundell
|
|
*/
|
|
#include <linux/ioport.h>
|
|
#include <linux/init.h>
|
|
#include <linux/dma-mapping.h>
|
|
|
|
#include <asm/dma.h>
|
|
#include <asm/io.h>
|
|
|
|
#include <asm/mach/dma.h>
|
|
|
|
#define ISA_DMA_MODE_READ 0x44
|
|
#define ISA_DMA_MODE_WRITE 0x48
|
|
#define ISA_DMA_MODE_CASCADE 0xc0
|
|
#define ISA_DMA_AUTOINIT 0x10
|
|
|
|
#define ISA_DMA_MASK 0
|
|
#define ISA_DMA_MODE 1
|
|
#define ISA_DMA_CLRFF 2
|
|
#define ISA_DMA_PGHI 3
|
|
#define ISA_DMA_PGLO 4
|
|
#define ISA_DMA_ADDR 5
|
|
#define ISA_DMA_COUNT 6
|
|
|
|
static unsigned int isa_dma_port[8][7] = {
|
|
/* MASK MODE CLRFF PAGE_HI PAGE_LO ADDR COUNT */
|
|
{ 0x0a, 0x0b, 0x0c, 0x487, 0x087, 0x00, 0x01 },
|
|
{ 0x0a, 0x0b, 0x0c, 0x483, 0x083, 0x02, 0x03 },
|
|
{ 0x0a, 0x0b, 0x0c, 0x481, 0x081, 0x04, 0x05 },
|
|
{ 0x0a, 0x0b, 0x0c, 0x482, 0x082, 0x06, 0x07 },
|
|
{ 0xd4, 0xd6, 0xd8, 0x000, 0x000, 0xc0, 0xc2 },
|
|
{ 0xd4, 0xd6, 0xd8, 0x48b, 0x08b, 0xc4, 0xc6 },
|
|
{ 0xd4, 0xd6, 0xd8, 0x489, 0x089, 0xc8, 0xca },
|
|
{ 0xd4, 0xd6, 0xd8, 0x48a, 0x08a, 0xcc, 0xce }
|
|
};
|
|
|
|
static int isa_get_dma_residue(dmach_t channel, dma_t *dma)
|
|
{
|
|
unsigned int io_port = isa_dma_port[channel][ISA_DMA_COUNT];
|
|
int count;
|
|
|
|
count = 1 + inb(io_port);
|
|
count |= inb(io_port) << 8;
|
|
|
|
return channel < 4 ? count : (count << 1);
|
|
}
|
|
|
|
static void isa_enable_dma(dmach_t channel, dma_t *dma)
|
|
{
|
|
if (dma->invalid) {
|
|
unsigned long address, length;
|
|
unsigned int mode;
|
|
enum dma_data_direction direction;
|
|
|
|
mode = channel & 3;
|
|
switch (dma->dma_mode & DMA_MODE_MASK) {
|
|
case DMA_MODE_READ:
|
|
mode |= ISA_DMA_MODE_READ;
|
|
direction = DMA_FROM_DEVICE;
|
|
break;
|
|
|
|
case DMA_MODE_WRITE:
|
|
mode |= ISA_DMA_MODE_WRITE;
|
|
direction = DMA_TO_DEVICE;
|
|
break;
|
|
|
|
case DMA_MODE_CASCADE:
|
|
mode |= ISA_DMA_MODE_CASCADE;
|
|
direction = DMA_BIDIRECTIONAL;
|
|
break;
|
|
|
|
default:
|
|
direction = DMA_NONE;
|
|
break;
|
|
}
|
|
|
|
if (!dma->sg) {
|
|
/*
|
|
* Cope with ISA-style drivers which expect cache
|
|
* coherence.
|
|
*/
|
|
dma->sg = &dma->buf;
|
|
dma->sgcount = 1;
|
|
dma->buf.length = dma->count;
|
|
dma->buf.dma_address = dma_map_single(NULL,
|
|
dma->addr, dma->count,
|
|
direction);
|
|
}
|
|
|
|
address = dma->buf.dma_address;
|
|
length = dma->buf.length - 1;
|
|
|
|
outb(address >> 16, isa_dma_port[channel][ISA_DMA_PGLO]);
|
|
outb(address >> 24, isa_dma_port[channel][ISA_DMA_PGHI]);
|
|
|
|
if (channel >= 4) {
|
|
address >>= 1;
|
|
length >>= 1;
|
|
}
|
|
|
|
outb(0, isa_dma_port[channel][ISA_DMA_CLRFF]);
|
|
|
|
outb(address, isa_dma_port[channel][ISA_DMA_ADDR]);
|
|
outb(address >> 8, isa_dma_port[channel][ISA_DMA_ADDR]);
|
|
|
|
outb(length, isa_dma_port[channel][ISA_DMA_COUNT]);
|
|
outb(length >> 8, isa_dma_port[channel][ISA_DMA_COUNT]);
|
|
|
|
if (dma->dma_mode & DMA_AUTOINIT)
|
|
mode |= ISA_DMA_AUTOINIT;
|
|
|
|
outb(mode, isa_dma_port[channel][ISA_DMA_MODE]);
|
|
dma->invalid = 0;
|
|
}
|
|
outb(channel & 3, isa_dma_port[channel][ISA_DMA_MASK]);
|
|
}
|
|
|
|
static void isa_disable_dma(dmach_t channel, dma_t *dma)
|
|
{
|
|
outb(channel | 4, isa_dma_port[channel][ISA_DMA_MASK]);
|
|
}
|
|
|
|
static struct dma_ops isa_dma_ops = {
|
|
.type = "ISA",
|
|
.enable = isa_enable_dma,
|
|
.disable = isa_disable_dma,
|
|
.residue = isa_get_dma_residue,
|
|
};
|
|
|
|
static struct resource dma_resources[] = { {
|
|
.name = "dma1",
|
|
.start = 0x0000,
|
|
.end = 0x000f
|
|
}, {
|
|
.name = "dma low page",
|
|
.start = 0x0080,
|
|
.end = 0x008f
|
|
}, {
|
|
.name = "dma2",
|
|
.start = 0x00c0,
|
|
.end = 0x00df
|
|
}, {
|
|
.name = "dma high page",
|
|
.start = 0x0480,
|
|
.end = 0x048f
|
|
} };
|
|
|
|
void __init isa_init_dma(dma_t *dma)
|
|
{
|
|
/*
|
|
* Try to autodetect presence of an ISA DMA controller.
|
|
* We do some minimal initialisation, and check that
|
|
* channel 0's DMA address registers are writeable.
|
|
*/
|
|
outb(0xff, 0x0d);
|
|
outb(0xff, 0xda);
|
|
|
|
/*
|
|
* Write high and low address, and then read them back
|
|
* in the same order.
|
|
*/
|
|
outb(0x55, 0x00);
|
|
outb(0xaa, 0x00);
|
|
|
|
if (inb(0) == 0x55 && inb(0) == 0xaa) {
|
|
int channel, i;
|
|
|
|
for (channel = 0; channel < 8; channel++) {
|
|
dma[channel].d_ops = &isa_dma_ops;
|
|
isa_disable_dma(channel, NULL);
|
|
}
|
|
|
|
outb(0x40, 0x0b);
|
|
outb(0x41, 0x0b);
|
|
outb(0x42, 0x0b);
|
|
outb(0x43, 0x0b);
|
|
|
|
outb(0xc0, 0xd6);
|
|
outb(0x41, 0xd6);
|
|
outb(0x42, 0xd6);
|
|
outb(0x43, 0xd6);
|
|
|
|
outb(0, 0xd4);
|
|
|
|
outb(0x10, 0x08);
|
|
outb(0x10, 0xd0);
|
|
|
|
/*
|
|
* Is this correct? According to my documentation, it
|
|
* doesn't appear to be. It should be:
|
|
* outb(0x3f, 0x40b); outb(0x3f, 0x4d6);
|
|
*/
|
|
outb(0x30, 0x40b);
|
|
outb(0x31, 0x40b);
|
|
outb(0x32, 0x40b);
|
|
outb(0x33, 0x40b);
|
|
outb(0x31, 0x4d6);
|
|
outb(0x32, 0x4d6);
|
|
outb(0x33, 0x4d6);
|
|
|
|
request_dma(DMA_ISA_CASCADE, "cascade");
|
|
|
|
for (i = 0; i < ARRAY_SIZE(dma_resources); i++)
|
|
request_resource(&ioport_resource, dma_resources + i);
|
|
}
|
|
}
|