![Greg Kroah-Hartman](/assets/img/avatar_default.png)
CONFIG_HOTPLUG is going away as an option. As a result, the __dev* markings need to be removed. This change removes the use of __devinit, __devexit_p, __devinitconst, and __devexit from these drivers. Based on patches originally written by Bill Pemberton, but redone by me in order to handle some of the coding style issues better, by hand. Cc: Bill Pemberton <wfp5p@virginia.edu> Cc: Viresh Kumar <viresh.linux@gmail.com> Cc: Dan Williams <djbw@fb.com> Cc: Vinod Koul <vinod.koul@intel.com> Cc: Barry Song <baohua.song@csr.com> Cc: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Cc: Alexander Duyck <alexander.h.duyck@intel.com> Cc: Russell King <rmk+kernel@arm.linux.org.uk> Cc: Linus Walleij <linus.walleij@linaro.org> Cc: Jassi Brar <jassisinghbrar@gmail.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Bill Pemberton <wfp5p@virginia.edu> Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1728 lines
44 KiB
C
1728 lines
44 KiB
C
/*
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* Driver for the Synopsys DesignWare DMA Controller (aka DMACA on
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* AVR32 systems.)
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*
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* Copyright (C) 2007-2008 Atmel Corporation
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* Copyright (C) 2010-2011 ST Microelectronics
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#include <linux/bitops.h>
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#include <linux/clk.h>
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#include <linux/delay.h>
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#include <linux/dmaengine.h>
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#include <linux/dma-mapping.h>
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#include <linux/init.h>
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#include <linux/interrupt.h>
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#include <linux/io.h>
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#include <linux/of.h>
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#include <linux/mm.h>
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#include <linux/module.h>
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#include <linux/platform_device.h>
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#include <linux/slab.h>
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#include "dw_dmac_regs.h"
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#include "dmaengine.h"
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/*
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* This supports the Synopsys "DesignWare AHB Central DMA Controller",
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* (DW_ahb_dmac) which is used with various AMBA 2.0 systems (not all
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* of which use ARM any more). See the "Databook" from Synopsys for
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* information beyond what licensees probably provide.
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*
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* The driver has currently been tested only with the Atmel AT32AP7000,
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* which does not support descriptor writeback.
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*/
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static inline unsigned int dwc_get_dms(struct dw_dma_slave *slave)
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{
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return slave ? slave->dst_master : 0;
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}
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static inline unsigned int dwc_get_sms(struct dw_dma_slave *slave)
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{
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return slave ? slave->src_master : 1;
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}
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#define DWC_DEFAULT_CTLLO(_chan) ({ \
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struct dw_dma_slave *__slave = (_chan->private); \
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struct dw_dma_chan *_dwc = to_dw_dma_chan(_chan); \
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struct dma_slave_config *_sconfig = &_dwc->dma_sconfig; \
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int _dms = dwc_get_dms(__slave); \
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int _sms = dwc_get_sms(__slave); \
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u8 _smsize = __slave ? _sconfig->src_maxburst : \
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DW_DMA_MSIZE_16; \
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u8 _dmsize = __slave ? _sconfig->dst_maxburst : \
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DW_DMA_MSIZE_16; \
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\
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(DWC_CTLL_DST_MSIZE(_dmsize) \
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| DWC_CTLL_SRC_MSIZE(_smsize) \
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| DWC_CTLL_LLP_D_EN \
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| DWC_CTLL_LLP_S_EN \
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| DWC_CTLL_DMS(_dms) \
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| DWC_CTLL_SMS(_sms)); \
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})
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/*
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* Number of descriptors to allocate for each channel. This should be
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* made configurable somehow; preferably, the clients (at least the
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* ones using slave transfers) should be able to give us a hint.
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*/
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#define NR_DESCS_PER_CHANNEL 64
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/*----------------------------------------------------------------------*/
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/*
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* Because we're not relying on writeback from the controller (it may not
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* even be configured into the core!) we don't need to use dma_pool. These
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* descriptors -- and associated data -- are cacheable. We do need to make
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* sure their dcache entries are written back before handing them off to
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* the controller, though.
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*/
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static struct device *chan2dev(struct dma_chan *chan)
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{
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return &chan->dev->device;
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}
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static struct device *chan2parent(struct dma_chan *chan)
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{
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return chan->dev->device.parent;
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}
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static struct dw_desc *dwc_first_active(struct dw_dma_chan *dwc)
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{
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return list_entry(dwc->active_list.next, struct dw_desc, desc_node);
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}
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static struct dw_desc *dwc_desc_get(struct dw_dma_chan *dwc)
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{
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struct dw_desc *desc, *_desc;
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struct dw_desc *ret = NULL;
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unsigned int i = 0;
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unsigned long flags;
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spin_lock_irqsave(&dwc->lock, flags);
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list_for_each_entry_safe(desc, _desc, &dwc->free_list, desc_node) {
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i++;
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if (async_tx_test_ack(&desc->txd)) {
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list_del(&desc->desc_node);
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ret = desc;
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break;
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}
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dev_dbg(chan2dev(&dwc->chan), "desc %p not ACKed\n", desc);
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}
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spin_unlock_irqrestore(&dwc->lock, flags);
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dev_vdbg(chan2dev(&dwc->chan), "scanned %u descriptors on freelist\n", i);
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return ret;
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}
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static void dwc_sync_desc_for_cpu(struct dw_dma_chan *dwc, struct dw_desc *desc)
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{
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struct dw_desc *child;
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list_for_each_entry(child, &desc->tx_list, desc_node)
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dma_sync_single_for_cpu(chan2parent(&dwc->chan),
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child->txd.phys, sizeof(child->lli),
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DMA_TO_DEVICE);
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dma_sync_single_for_cpu(chan2parent(&dwc->chan),
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desc->txd.phys, sizeof(desc->lli),
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DMA_TO_DEVICE);
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}
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/*
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* Move a descriptor, including any children, to the free list.
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* `desc' must not be on any lists.
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*/
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static void dwc_desc_put(struct dw_dma_chan *dwc, struct dw_desc *desc)
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{
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unsigned long flags;
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if (desc) {
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struct dw_desc *child;
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dwc_sync_desc_for_cpu(dwc, desc);
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spin_lock_irqsave(&dwc->lock, flags);
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list_for_each_entry(child, &desc->tx_list, desc_node)
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dev_vdbg(chan2dev(&dwc->chan),
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"moving child desc %p to freelist\n",
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child);
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list_splice_init(&desc->tx_list, &dwc->free_list);
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dev_vdbg(chan2dev(&dwc->chan), "moving desc %p to freelist\n", desc);
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list_add(&desc->desc_node, &dwc->free_list);
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spin_unlock_irqrestore(&dwc->lock, flags);
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}
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}
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static void dwc_initialize(struct dw_dma_chan *dwc)
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{
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struct dw_dma *dw = to_dw_dma(dwc->chan.device);
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struct dw_dma_slave *dws = dwc->chan.private;
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u32 cfghi = DWC_CFGH_FIFO_MODE;
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u32 cfglo = DWC_CFGL_CH_PRIOR(dwc->priority);
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if (dwc->initialized == true)
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return;
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if (dws) {
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/*
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* We need controller-specific data to set up slave
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* transfers.
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*/
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BUG_ON(!dws->dma_dev || dws->dma_dev != dw->dma.dev);
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cfghi = dws->cfg_hi;
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cfglo |= dws->cfg_lo & ~DWC_CFGL_CH_PRIOR_MASK;
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} else {
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if (dwc->dma_sconfig.direction == DMA_MEM_TO_DEV)
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cfghi = DWC_CFGH_DST_PER(dwc->dma_sconfig.slave_id);
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else if (dwc->dma_sconfig.direction == DMA_DEV_TO_MEM)
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cfghi = DWC_CFGH_SRC_PER(dwc->dma_sconfig.slave_id);
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}
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channel_writel(dwc, CFG_LO, cfglo);
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channel_writel(dwc, CFG_HI, cfghi);
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/* Enable interrupts */
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channel_set_bit(dw, MASK.XFER, dwc->mask);
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channel_set_bit(dw, MASK.ERROR, dwc->mask);
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dwc->initialized = true;
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}
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/*----------------------------------------------------------------------*/
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static inline unsigned int dwc_fast_fls(unsigned long long v)
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{
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/*
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* We can be a lot more clever here, but this should take care
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* of the most common optimization.
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*/
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if (!(v & 7))
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return 3;
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else if (!(v & 3))
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return 2;
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else if (!(v & 1))
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return 1;
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return 0;
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}
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static inline void dwc_dump_chan_regs(struct dw_dma_chan *dwc)
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{
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dev_err(chan2dev(&dwc->chan),
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" SAR: 0x%x DAR: 0x%x LLP: 0x%x CTL: 0x%x:%08x\n",
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channel_readl(dwc, SAR),
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channel_readl(dwc, DAR),
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channel_readl(dwc, LLP),
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channel_readl(dwc, CTL_HI),
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channel_readl(dwc, CTL_LO));
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}
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static inline void dwc_chan_disable(struct dw_dma *dw, struct dw_dma_chan *dwc)
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{
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channel_clear_bit(dw, CH_EN, dwc->mask);
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while (dma_readl(dw, CH_EN) & dwc->mask)
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cpu_relax();
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}
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/*----------------------------------------------------------------------*/
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/* Perform single block transfer */
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static inline void dwc_do_single_block(struct dw_dma_chan *dwc,
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struct dw_desc *desc)
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{
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struct dw_dma *dw = to_dw_dma(dwc->chan.device);
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u32 ctllo;
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/* Software emulation of LLP mode relies on interrupts to continue
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* multi block transfer. */
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ctllo = desc->lli.ctllo | DWC_CTLL_INT_EN;
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channel_writel(dwc, SAR, desc->lli.sar);
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channel_writel(dwc, DAR, desc->lli.dar);
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channel_writel(dwc, CTL_LO, ctllo);
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channel_writel(dwc, CTL_HI, desc->lli.ctlhi);
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channel_set_bit(dw, CH_EN, dwc->mask);
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}
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/* Called with dwc->lock held and bh disabled */
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static void dwc_dostart(struct dw_dma_chan *dwc, struct dw_desc *first)
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{
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struct dw_dma *dw = to_dw_dma(dwc->chan.device);
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unsigned long was_soft_llp;
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/* ASSERT: channel is idle */
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if (dma_readl(dw, CH_EN) & dwc->mask) {
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dev_err(chan2dev(&dwc->chan),
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"BUG: Attempted to start non-idle channel\n");
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dwc_dump_chan_regs(dwc);
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/* The tasklet will hopefully advance the queue... */
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return;
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}
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if (dwc->nollp) {
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was_soft_llp = test_and_set_bit(DW_DMA_IS_SOFT_LLP,
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&dwc->flags);
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if (was_soft_llp) {
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dev_err(chan2dev(&dwc->chan),
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"BUG: Attempted to start new LLP transfer "
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"inside ongoing one\n");
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return;
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}
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dwc_initialize(dwc);
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dwc->tx_list = &first->tx_list;
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dwc->tx_node_active = first->tx_list.next;
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dwc_do_single_block(dwc, first);
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return;
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}
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dwc_initialize(dwc);
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channel_writel(dwc, LLP, first->txd.phys);
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channel_writel(dwc, CTL_LO,
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DWC_CTLL_LLP_D_EN | DWC_CTLL_LLP_S_EN);
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channel_writel(dwc, CTL_HI, 0);
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channel_set_bit(dw, CH_EN, dwc->mask);
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}
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/*----------------------------------------------------------------------*/
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static void
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dwc_descriptor_complete(struct dw_dma_chan *dwc, struct dw_desc *desc,
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bool callback_required)
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{
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dma_async_tx_callback callback = NULL;
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void *param = NULL;
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struct dma_async_tx_descriptor *txd = &desc->txd;
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struct dw_desc *child;
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unsigned long flags;
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dev_vdbg(chan2dev(&dwc->chan), "descriptor %u complete\n", txd->cookie);
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spin_lock_irqsave(&dwc->lock, flags);
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dma_cookie_complete(txd);
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if (callback_required) {
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callback = txd->callback;
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param = txd->callback_param;
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}
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dwc_sync_desc_for_cpu(dwc, desc);
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/* async_tx_ack */
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list_for_each_entry(child, &desc->tx_list, desc_node)
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async_tx_ack(&child->txd);
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async_tx_ack(&desc->txd);
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list_splice_init(&desc->tx_list, &dwc->free_list);
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list_move(&desc->desc_node, &dwc->free_list);
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if (!dwc->chan.private) {
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struct device *parent = chan2parent(&dwc->chan);
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if (!(txd->flags & DMA_COMPL_SKIP_DEST_UNMAP)) {
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if (txd->flags & DMA_COMPL_DEST_UNMAP_SINGLE)
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dma_unmap_single(parent, desc->lli.dar,
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desc->len, DMA_FROM_DEVICE);
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else
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dma_unmap_page(parent, desc->lli.dar,
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desc->len, DMA_FROM_DEVICE);
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}
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if (!(txd->flags & DMA_COMPL_SKIP_SRC_UNMAP)) {
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if (txd->flags & DMA_COMPL_SRC_UNMAP_SINGLE)
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dma_unmap_single(parent, desc->lli.sar,
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desc->len, DMA_TO_DEVICE);
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else
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dma_unmap_page(parent, desc->lli.sar,
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desc->len, DMA_TO_DEVICE);
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}
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}
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spin_unlock_irqrestore(&dwc->lock, flags);
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if (callback_required && callback)
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callback(param);
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}
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static void dwc_complete_all(struct dw_dma *dw, struct dw_dma_chan *dwc)
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{
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struct dw_desc *desc, *_desc;
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LIST_HEAD(list);
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unsigned long flags;
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spin_lock_irqsave(&dwc->lock, flags);
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if (dma_readl(dw, CH_EN) & dwc->mask) {
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dev_err(chan2dev(&dwc->chan),
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"BUG: XFER bit set, but channel not idle!\n");
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/* Try to continue after resetting the channel... */
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dwc_chan_disable(dw, dwc);
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}
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/*
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* Submit queued descriptors ASAP, i.e. before we go through
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* the completed ones.
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*/
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list_splice_init(&dwc->active_list, &list);
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if (!list_empty(&dwc->queue)) {
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list_move(dwc->queue.next, &dwc->active_list);
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dwc_dostart(dwc, dwc_first_active(dwc));
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}
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spin_unlock_irqrestore(&dwc->lock, flags);
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list_for_each_entry_safe(desc, _desc, &list, desc_node)
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dwc_descriptor_complete(dwc, desc, true);
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}
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static void dwc_scan_descriptors(struct dw_dma *dw, struct dw_dma_chan *dwc)
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{
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dma_addr_t llp;
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struct dw_desc *desc, *_desc;
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struct dw_desc *child;
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u32 status_xfer;
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unsigned long flags;
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spin_lock_irqsave(&dwc->lock, flags);
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llp = channel_readl(dwc, LLP);
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status_xfer = dma_readl(dw, RAW.XFER);
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if (status_xfer & dwc->mask) {
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/* Everything we've submitted is done */
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dma_writel(dw, CLEAR.XFER, dwc->mask);
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spin_unlock_irqrestore(&dwc->lock, flags);
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dwc_complete_all(dw, dwc);
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return;
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}
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if (list_empty(&dwc->active_list)) {
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spin_unlock_irqrestore(&dwc->lock, flags);
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return;
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}
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dev_vdbg(chan2dev(&dwc->chan), "%s: llp=0x%llx\n", __func__,
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(unsigned long long)llp);
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list_for_each_entry_safe(desc, _desc, &dwc->active_list, desc_node) {
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/* check first descriptors addr */
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if (desc->txd.phys == llp) {
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spin_unlock_irqrestore(&dwc->lock, flags);
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return;
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}
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/* check first descriptors llp */
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if (desc->lli.llp == llp) {
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/* This one is currently in progress */
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spin_unlock_irqrestore(&dwc->lock, flags);
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return;
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}
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list_for_each_entry(child, &desc->tx_list, desc_node)
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if (child->lli.llp == llp) {
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/* Currently in progress */
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spin_unlock_irqrestore(&dwc->lock, flags);
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return;
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}
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/*
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* No descriptors so far seem to be in progress, i.e.
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* this one must be done.
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*/
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spin_unlock_irqrestore(&dwc->lock, flags);
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dwc_descriptor_complete(dwc, desc, true);
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spin_lock_irqsave(&dwc->lock, flags);
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}
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dev_err(chan2dev(&dwc->chan),
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"BUG: All descriptors done, but channel not idle!\n");
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/* Try to continue after resetting the channel... */
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dwc_chan_disable(dw, dwc);
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if (!list_empty(&dwc->queue)) {
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list_move(dwc->queue.next, &dwc->active_list);
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dwc_dostart(dwc, dwc_first_active(dwc));
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}
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spin_unlock_irqrestore(&dwc->lock, flags);
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}
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static inline void dwc_dump_lli(struct dw_dma_chan *dwc, struct dw_lli *lli)
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{
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dev_printk(KERN_CRIT, chan2dev(&dwc->chan),
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" desc: s0x%x d0x%x l0x%x c0x%x:%x\n",
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lli->sar, lli->dar, lli->llp, lli->ctlhi, lli->ctllo);
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}
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static void dwc_handle_error(struct dw_dma *dw, struct dw_dma_chan *dwc)
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{
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struct dw_desc *bad_desc;
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|
struct dw_desc *child;
|
|
unsigned long flags;
|
|
|
|
dwc_scan_descriptors(dw, dwc);
|
|
|
|
spin_lock_irqsave(&dwc->lock, flags);
|
|
|
|
/*
|
|
* The descriptor currently at the head of the active list is
|
|
* borked. Since we don't have any way to report errors, we'll
|
|
* just have to scream loudly and try to carry on.
|
|
*/
|
|
bad_desc = dwc_first_active(dwc);
|
|
list_del_init(&bad_desc->desc_node);
|
|
list_move(dwc->queue.next, dwc->active_list.prev);
|
|
|
|
/* Clear the error flag and try to restart the controller */
|
|
dma_writel(dw, CLEAR.ERROR, dwc->mask);
|
|
if (!list_empty(&dwc->active_list))
|
|
dwc_dostart(dwc, dwc_first_active(dwc));
|
|
|
|
/*
|
|
* KERN_CRITICAL may seem harsh, but since this only happens
|
|
* when someone submits a bad physical address in a
|
|
* descriptor, we should consider ourselves lucky that the
|
|
* controller flagged an error instead of scribbling over
|
|
* random memory locations.
|
|
*/
|
|
dev_printk(KERN_CRIT, chan2dev(&dwc->chan),
|
|
"Bad descriptor submitted for DMA!\n");
|
|
dev_printk(KERN_CRIT, chan2dev(&dwc->chan),
|
|
" cookie: %d\n", bad_desc->txd.cookie);
|
|
dwc_dump_lli(dwc, &bad_desc->lli);
|
|
list_for_each_entry(child, &bad_desc->tx_list, desc_node)
|
|
dwc_dump_lli(dwc, &child->lli);
|
|
|
|
spin_unlock_irqrestore(&dwc->lock, flags);
|
|
|
|
/* Pretend the descriptor completed successfully */
|
|
dwc_descriptor_complete(dwc, bad_desc, true);
|
|
}
|
|
|
|
/* --------------------- Cyclic DMA API extensions -------------------- */
|
|
|
|
inline dma_addr_t dw_dma_get_src_addr(struct dma_chan *chan)
|
|
{
|
|
struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
|
|
return channel_readl(dwc, SAR);
|
|
}
|
|
EXPORT_SYMBOL(dw_dma_get_src_addr);
|
|
|
|
inline dma_addr_t dw_dma_get_dst_addr(struct dma_chan *chan)
|
|
{
|
|
struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
|
|
return channel_readl(dwc, DAR);
|
|
}
|
|
EXPORT_SYMBOL(dw_dma_get_dst_addr);
|
|
|
|
/* called with dwc->lock held and all DMAC interrupts disabled */
|
|
static void dwc_handle_cyclic(struct dw_dma *dw, struct dw_dma_chan *dwc,
|
|
u32 status_err, u32 status_xfer)
|
|
{
|
|
unsigned long flags;
|
|
|
|
if (dwc->mask) {
|
|
void (*callback)(void *param);
|
|
void *callback_param;
|
|
|
|
dev_vdbg(chan2dev(&dwc->chan), "new cyclic period llp 0x%08x\n",
|
|
channel_readl(dwc, LLP));
|
|
|
|
callback = dwc->cdesc->period_callback;
|
|
callback_param = dwc->cdesc->period_callback_param;
|
|
|
|
if (callback)
|
|
callback(callback_param);
|
|
}
|
|
|
|
/*
|
|
* Error and transfer complete are highly unlikely, and will most
|
|
* likely be due to a configuration error by the user.
|
|
*/
|
|
if (unlikely(status_err & dwc->mask) ||
|
|
unlikely(status_xfer & dwc->mask)) {
|
|
int i;
|
|
|
|
dev_err(chan2dev(&dwc->chan), "cyclic DMA unexpected %s "
|
|
"interrupt, stopping DMA transfer\n",
|
|
status_xfer ? "xfer" : "error");
|
|
|
|
spin_lock_irqsave(&dwc->lock, flags);
|
|
|
|
dwc_dump_chan_regs(dwc);
|
|
|
|
dwc_chan_disable(dw, dwc);
|
|
|
|
/* make sure DMA does not restart by loading a new list */
|
|
channel_writel(dwc, LLP, 0);
|
|
channel_writel(dwc, CTL_LO, 0);
|
|
channel_writel(dwc, CTL_HI, 0);
|
|
|
|
dma_writel(dw, CLEAR.ERROR, dwc->mask);
|
|
dma_writel(dw, CLEAR.XFER, dwc->mask);
|
|
|
|
for (i = 0; i < dwc->cdesc->periods; i++)
|
|
dwc_dump_lli(dwc, &dwc->cdesc->desc[i]->lli);
|
|
|
|
spin_unlock_irqrestore(&dwc->lock, flags);
|
|
}
|
|
}
|
|
|
|
/* ------------------------------------------------------------------------- */
|
|
|
|
static void dw_dma_tasklet(unsigned long data)
|
|
{
|
|
struct dw_dma *dw = (struct dw_dma *)data;
|
|
struct dw_dma_chan *dwc;
|
|
u32 status_xfer;
|
|
u32 status_err;
|
|
int i;
|
|
|
|
status_xfer = dma_readl(dw, RAW.XFER);
|
|
status_err = dma_readl(dw, RAW.ERROR);
|
|
|
|
dev_vdbg(dw->dma.dev, "%s: status_err=%x\n", __func__, status_err);
|
|
|
|
for (i = 0; i < dw->dma.chancnt; i++) {
|
|
dwc = &dw->chan[i];
|
|
if (test_bit(DW_DMA_IS_CYCLIC, &dwc->flags))
|
|
dwc_handle_cyclic(dw, dwc, status_err, status_xfer);
|
|
else if (status_err & (1 << i))
|
|
dwc_handle_error(dw, dwc);
|
|
else if (status_xfer & (1 << i)) {
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&dwc->lock, flags);
|
|
if (test_bit(DW_DMA_IS_SOFT_LLP, &dwc->flags)) {
|
|
if (dwc->tx_node_active != dwc->tx_list) {
|
|
struct dw_desc *desc =
|
|
list_entry(dwc->tx_node_active,
|
|
struct dw_desc,
|
|
desc_node);
|
|
|
|
dma_writel(dw, CLEAR.XFER, dwc->mask);
|
|
|
|
/* move pointer to next descriptor */
|
|
dwc->tx_node_active =
|
|
dwc->tx_node_active->next;
|
|
|
|
dwc_do_single_block(dwc, desc);
|
|
|
|
spin_unlock_irqrestore(&dwc->lock, flags);
|
|
continue;
|
|
} else {
|
|
/* we are done here */
|
|
clear_bit(DW_DMA_IS_SOFT_LLP, &dwc->flags);
|
|
}
|
|
}
|
|
spin_unlock_irqrestore(&dwc->lock, flags);
|
|
|
|
dwc_scan_descriptors(dw, dwc);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Re-enable interrupts.
|
|
*/
|
|
channel_set_bit(dw, MASK.XFER, dw->all_chan_mask);
|
|
channel_set_bit(dw, MASK.ERROR, dw->all_chan_mask);
|
|
}
|
|
|
|
static irqreturn_t dw_dma_interrupt(int irq, void *dev_id)
|
|
{
|
|
struct dw_dma *dw = dev_id;
|
|
u32 status;
|
|
|
|
dev_vdbg(dw->dma.dev, "%s: status=0x%x\n", __func__,
|
|
dma_readl(dw, STATUS_INT));
|
|
|
|
/*
|
|
* Just disable the interrupts. We'll turn them back on in the
|
|
* softirq handler.
|
|
*/
|
|
channel_clear_bit(dw, MASK.XFER, dw->all_chan_mask);
|
|
channel_clear_bit(dw, MASK.ERROR, dw->all_chan_mask);
|
|
|
|
status = dma_readl(dw, STATUS_INT);
|
|
if (status) {
|
|
dev_err(dw->dma.dev,
|
|
"BUG: Unexpected interrupts pending: 0x%x\n",
|
|
status);
|
|
|
|
/* Try to recover */
|
|
channel_clear_bit(dw, MASK.XFER, (1 << 8) - 1);
|
|
channel_clear_bit(dw, MASK.SRC_TRAN, (1 << 8) - 1);
|
|
channel_clear_bit(dw, MASK.DST_TRAN, (1 << 8) - 1);
|
|
channel_clear_bit(dw, MASK.ERROR, (1 << 8) - 1);
|
|
}
|
|
|
|
tasklet_schedule(&dw->tasklet);
|
|
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
/*----------------------------------------------------------------------*/
|
|
|
|
static dma_cookie_t dwc_tx_submit(struct dma_async_tx_descriptor *tx)
|
|
{
|
|
struct dw_desc *desc = txd_to_dw_desc(tx);
|
|
struct dw_dma_chan *dwc = to_dw_dma_chan(tx->chan);
|
|
dma_cookie_t cookie;
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&dwc->lock, flags);
|
|
cookie = dma_cookie_assign(tx);
|
|
|
|
/*
|
|
* REVISIT: We should attempt to chain as many descriptors as
|
|
* possible, perhaps even appending to those already submitted
|
|
* for DMA. But this is hard to do in a race-free manner.
|
|
*/
|
|
if (list_empty(&dwc->active_list)) {
|
|
dev_vdbg(chan2dev(tx->chan), "%s: started %u\n", __func__,
|
|
desc->txd.cookie);
|
|
list_add_tail(&desc->desc_node, &dwc->active_list);
|
|
dwc_dostart(dwc, dwc_first_active(dwc));
|
|
} else {
|
|
dev_vdbg(chan2dev(tx->chan), "%s: queued %u\n", __func__,
|
|
desc->txd.cookie);
|
|
|
|
list_add_tail(&desc->desc_node, &dwc->queue);
|
|
}
|
|
|
|
spin_unlock_irqrestore(&dwc->lock, flags);
|
|
|
|
return cookie;
|
|
}
|
|
|
|
static struct dma_async_tx_descriptor *
|
|
dwc_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
|
|
size_t len, unsigned long flags)
|
|
{
|
|
struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
|
|
struct dw_dma_slave *dws = chan->private;
|
|
struct dw_desc *desc;
|
|
struct dw_desc *first;
|
|
struct dw_desc *prev;
|
|
size_t xfer_count;
|
|
size_t offset;
|
|
unsigned int src_width;
|
|
unsigned int dst_width;
|
|
unsigned int data_width;
|
|
u32 ctllo;
|
|
|
|
dev_vdbg(chan2dev(chan),
|
|
"%s: d0x%llx s0x%llx l0x%zx f0x%lx\n", __func__,
|
|
(unsigned long long)dest, (unsigned long long)src,
|
|
len, flags);
|
|
|
|
if (unlikely(!len)) {
|
|
dev_dbg(chan2dev(chan), "%s: length is zero!\n", __func__);
|
|
return NULL;
|
|
}
|
|
|
|
data_width = min_t(unsigned int, dwc->dw->data_width[dwc_get_sms(dws)],
|
|
dwc->dw->data_width[dwc_get_dms(dws)]);
|
|
|
|
src_width = dst_width = min_t(unsigned int, data_width,
|
|
dwc_fast_fls(src | dest | len));
|
|
|
|
ctllo = DWC_DEFAULT_CTLLO(chan)
|
|
| DWC_CTLL_DST_WIDTH(dst_width)
|
|
| DWC_CTLL_SRC_WIDTH(src_width)
|
|
| DWC_CTLL_DST_INC
|
|
| DWC_CTLL_SRC_INC
|
|
| DWC_CTLL_FC_M2M;
|
|
prev = first = NULL;
|
|
|
|
for (offset = 0; offset < len; offset += xfer_count << src_width) {
|
|
xfer_count = min_t(size_t, (len - offset) >> src_width,
|
|
dwc->block_size);
|
|
|
|
desc = dwc_desc_get(dwc);
|
|
if (!desc)
|
|
goto err_desc_get;
|
|
|
|
desc->lli.sar = src + offset;
|
|
desc->lli.dar = dest + offset;
|
|
desc->lli.ctllo = ctllo;
|
|
desc->lli.ctlhi = xfer_count;
|
|
|
|
if (!first) {
|
|
first = desc;
|
|
} else {
|
|
prev->lli.llp = desc->txd.phys;
|
|
dma_sync_single_for_device(chan2parent(chan),
|
|
prev->txd.phys, sizeof(prev->lli),
|
|
DMA_TO_DEVICE);
|
|
list_add_tail(&desc->desc_node,
|
|
&first->tx_list);
|
|
}
|
|
prev = desc;
|
|
}
|
|
|
|
|
|
if (flags & DMA_PREP_INTERRUPT)
|
|
/* Trigger interrupt after last block */
|
|
prev->lli.ctllo |= DWC_CTLL_INT_EN;
|
|
|
|
prev->lli.llp = 0;
|
|
dma_sync_single_for_device(chan2parent(chan),
|
|
prev->txd.phys, sizeof(prev->lli),
|
|
DMA_TO_DEVICE);
|
|
|
|
first->txd.flags = flags;
|
|
first->len = len;
|
|
|
|
return &first->txd;
|
|
|
|
err_desc_get:
|
|
dwc_desc_put(dwc, first);
|
|
return NULL;
|
|
}
|
|
|
|
static struct dma_async_tx_descriptor *
|
|
dwc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
|
|
unsigned int sg_len, enum dma_transfer_direction direction,
|
|
unsigned long flags, void *context)
|
|
{
|
|
struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
|
|
struct dw_dma_slave *dws = chan->private;
|
|
struct dma_slave_config *sconfig = &dwc->dma_sconfig;
|
|
struct dw_desc *prev;
|
|
struct dw_desc *first;
|
|
u32 ctllo;
|
|
dma_addr_t reg;
|
|
unsigned int reg_width;
|
|
unsigned int mem_width;
|
|
unsigned int data_width;
|
|
unsigned int i;
|
|
struct scatterlist *sg;
|
|
size_t total_len = 0;
|
|
|
|
dev_vdbg(chan2dev(chan), "%s\n", __func__);
|
|
|
|
if (unlikely(!dws || !sg_len))
|
|
return NULL;
|
|
|
|
prev = first = NULL;
|
|
|
|
switch (direction) {
|
|
case DMA_MEM_TO_DEV:
|
|
reg_width = __fls(sconfig->dst_addr_width);
|
|
reg = sconfig->dst_addr;
|
|
ctllo = (DWC_DEFAULT_CTLLO(chan)
|
|
| DWC_CTLL_DST_WIDTH(reg_width)
|
|
| DWC_CTLL_DST_FIX
|
|
| DWC_CTLL_SRC_INC);
|
|
|
|
ctllo |= sconfig->device_fc ? DWC_CTLL_FC(DW_DMA_FC_P_M2P) :
|
|
DWC_CTLL_FC(DW_DMA_FC_D_M2P);
|
|
|
|
data_width = dwc->dw->data_width[dwc_get_sms(dws)];
|
|
|
|
for_each_sg(sgl, sg, sg_len, i) {
|
|
struct dw_desc *desc;
|
|
u32 len, dlen, mem;
|
|
|
|
mem = sg_dma_address(sg);
|
|
len = sg_dma_len(sg);
|
|
|
|
mem_width = min_t(unsigned int,
|
|
data_width, dwc_fast_fls(mem | len));
|
|
|
|
slave_sg_todev_fill_desc:
|
|
desc = dwc_desc_get(dwc);
|
|
if (!desc) {
|
|
dev_err(chan2dev(chan),
|
|
"not enough descriptors available\n");
|
|
goto err_desc_get;
|
|
}
|
|
|
|
desc->lli.sar = mem;
|
|
desc->lli.dar = reg;
|
|
desc->lli.ctllo = ctllo | DWC_CTLL_SRC_WIDTH(mem_width);
|
|
if ((len >> mem_width) > dwc->block_size) {
|
|
dlen = dwc->block_size << mem_width;
|
|
mem += dlen;
|
|
len -= dlen;
|
|
} else {
|
|
dlen = len;
|
|
len = 0;
|
|
}
|
|
|
|
desc->lli.ctlhi = dlen >> mem_width;
|
|
|
|
if (!first) {
|
|
first = desc;
|
|
} else {
|
|
prev->lli.llp = desc->txd.phys;
|
|
dma_sync_single_for_device(chan2parent(chan),
|
|
prev->txd.phys,
|
|
sizeof(prev->lli),
|
|
DMA_TO_DEVICE);
|
|
list_add_tail(&desc->desc_node,
|
|
&first->tx_list);
|
|
}
|
|
prev = desc;
|
|
total_len += dlen;
|
|
|
|
if (len)
|
|
goto slave_sg_todev_fill_desc;
|
|
}
|
|
break;
|
|
case DMA_DEV_TO_MEM:
|
|
reg_width = __fls(sconfig->src_addr_width);
|
|
reg = sconfig->src_addr;
|
|
ctllo = (DWC_DEFAULT_CTLLO(chan)
|
|
| DWC_CTLL_SRC_WIDTH(reg_width)
|
|
| DWC_CTLL_DST_INC
|
|
| DWC_CTLL_SRC_FIX);
|
|
|
|
ctllo |= sconfig->device_fc ? DWC_CTLL_FC(DW_DMA_FC_P_P2M) :
|
|
DWC_CTLL_FC(DW_DMA_FC_D_P2M);
|
|
|
|
data_width = dwc->dw->data_width[dwc_get_dms(dws)];
|
|
|
|
for_each_sg(sgl, sg, sg_len, i) {
|
|
struct dw_desc *desc;
|
|
u32 len, dlen, mem;
|
|
|
|
mem = sg_dma_address(sg);
|
|
len = sg_dma_len(sg);
|
|
|
|
mem_width = min_t(unsigned int,
|
|
data_width, dwc_fast_fls(mem | len));
|
|
|
|
slave_sg_fromdev_fill_desc:
|
|
desc = dwc_desc_get(dwc);
|
|
if (!desc) {
|
|
dev_err(chan2dev(chan),
|
|
"not enough descriptors available\n");
|
|
goto err_desc_get;
|
|
}
|
|
|
|
desc->lli.sar = reg;
|
|
desc->lli.dar = mem;
|
|
desc->lli.ctllo = ctllo | DWC_CTLL_DST_WIDTH(mem_width);
|
|
if ((len >> reg_width) > dwc->block_size) {
|
|
dlen = dwc->block_size << reg_width;
|
|
mem += dlen;
|
|
len -= dlen;
|
|
} else {
|
|
dlen = len;
|
|
len = 0;
|
|
}
|
|
desc->lli.ctlhi = dlen >> reg_width;
|
|
|
|
if (!first) {
|
|
first = desc;
|
|
} else {
|
|
prev->lli.llp = desc->txd.phys;
|
|
dma_sync_single_for_device(chan2parent(chan),
|
|
prev->txd.phys,
|
|
sizeof(prev->lli),
|
|
DMA_TO_DEVICE);
|
|
list_add_tail(&desc->desc_node,
|
|
&first->tx_list);
|
|
}
|
|
prev = desc;
|
|
total_len += dlen;
|
|
|
|
if (len)
|
|
goto slave_sg_fromdev_fill_desc;
|
|
}
|
|
break;
|
|
default:
|
|
return NULL;
|
|
}
|
|
|
|
if (flags & DMA_PREP_INTERRUPT)
|
|
/* Trigger interrupt after last block */
|
|
prev->lli.ctllo |= DWC_CTLL_INT_EN;
|
|
|
|
prev->lli.llp = 0;
|
|
dma_sync_single_for_device(chan2parent(chan),
|
|
prev->txd.phys, sizeof(prev->lli),
|
|
DMA_TO_DEVICE);
|
|
|
|
first->len = total_len;
|
|
|
|
return &first->txd;
|
|
|
|
err_desc_get:
|
|
dwc_desc_put(dwc, first);
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* Fix sconfig's burst size according to dw_dmac. We need to convert them as:
|
|
* 1 -> 0, 4 -> 1, 8 -> 2, 16 -> 3.
|
|
*
|
|
* NOTE: burst size 2 is not supported by controller.
|
|
*
|
|
* This can be done by finding least significant bit set: n & (n - 1)
|
|
*/
|
|
static inline void convert_burst(u32 *maxburst)
|
|
{
|
|
if (*maxburst > 1)
|
|
*maxburst = fls(*maxburst) - 2;
|
|
else
|
|
*maxburst = 0;
|
|
}
|
|
|
|
static int
|
|
set_runtime_config(struct dma_chan *chan, struct dma_slave_config *sconfig)
|
|
{
|
|
struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
|
|
|
|
/* Check if it is chan is configured for slave transfers */
|
|
if (!chan->private)
|
|
return -EINVAL;
|
|
|
|
memcpy(&dwc->dma_sconfig, sconfig, sizeof(*sconfig));
|
|
|
|
convert_burst(&dwc->dma_sconfig.src_maxburst);
|
|
convert_burst(&dwc->dma_sconfig.dst_maxburst);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int dwc_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
|
|
unsigned long arg)
|
|
{
|
|
struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
|
|
struct dw_dma *dw = to_dw_dma(chan->device);
|
|
struct dw_desc *desc, *_desc;
|
|
unsigned long flags;
|
|
u32 cfglo;
|
|
LIST_HEAD(list);
|
|
|
|
if (cmd == DMA_PAUSE) {
|
|
spin_lock_irqsave(&dwc->lock, flags);
|
|
|
|
cfglo = channel_readl(dwc, CFG_LO);
|
|
channel_writel(dwc, CFG_LO, cfglo | DWC_CFGL_CH_SUSP);
|
|
while (!(channel_readl(dwc, CFG_LO) & DWC_CFGL_FIFO_EMPTY))
|
|
cpu_relax();
|
|
|
|
dwc->paused = true;
|
|
spin_unlock_irqrestore(&dwc->lock, flags);
|
|
} else if (cmd == DMA_RESUME) {
|
|
if (!dwc->paused)
|
|
return 0;
|
|
|
|
spin_lock_irqsave(&dwc->lock, flags);
|
|
|
|
cfglo = channel_readl(dwc, CFG_LO);
|
|
channel_writel(dwc, CFG_LO, cfglo & ~DWC_CFGL_CH_SUSP);
|
|
dwc->paused = false;
|
|
|
|
spin_unlock_irqrestore(&dwc->lock, flags);
|
|
} else if (cmd == DMA_TERMINATE_ALL) {
|
|
spin_lock_irqsave(&dwc->lock, flags);
|
|
|
|
clear_bit(DW_DMA_IS_SOFT_LLP, &dwc->flags);
|
|
|
|
dwc_chan_disable(dw, dwc);
|
|
|
|
dwc->paused = false;
|
|
|
|
/* active_list entries will end up before queued entries */
|
|
list_splice_init(&dwc->queue, &list);
|
|
list_splice_init(&dwc->active_list, &list);
|
|
|
|
spin_unlock_irqrestore(&dwc->lock, flags);
|
|
|
|
/* Flush all pending and queued descriptors */
|
|
list_for_each_entry_safe(desc, _desc, &list, desc_node)
|
|
dwc_descriptor_complete(dwc, desc, false);
|
|
} else if (cmd == DMA_SLAVE_CONFIG) {
|
|
return set_runtime_config(chan, (struct dma_slave_config *)arg);
|
|
} else {
|
|
return -ENXIO;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static enum dma_status
|
|
dwc_tx_status(struct dma_chan *chan,
|
|
dma_cookie_t cookie,
|
|
struct dma_tx_state *txstate)
|
|
{
|
|
struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
|
|
enum dma_status ret;
|
|
|
|
ret = dma_cookie_status(chan, cookie, txstate);
|
|
if (ret != DMA_SUCCESS) {
|
|
dwc_scan_descriptors(to_dw_dma(chan->device), dwc);
|
|
|
|
ret = dma_cookie_status(chan, cookie, txstate);
|
|
}
|
|
|
|
if (ret != DMA_SUCCESS)
|
|
dma_set_residue(txstate, dwc_first_active(dwc)->len);
|
|
|
|
if (dwc->paused)
|
|
return DMA_PAUSED;
|
|
|
|
return ret;
|
|
}
|
|
|
|
static void dwc_issue_pending(struct dma_chan *chan)
|
|
{
|
|
struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
|
|
|
|
if (!list_empty(&dwc->queue))
|
|
dwc_scan_descriptors(to_dw_dma(chan->device), dwc);
|
|
}
|
|
|
|
static int dwc_alloc_chan_resources(struct dma_chan *chan)
|
|
{
|
|
struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
|
|
struct dw_dma *dw = to_dw_dma(chan->device);
|
|
struct dw_desc *desc;
|
|
int i;
|
|
unsigned long flags;
|
|
|
|
dev_vdbg(chan2dev(chan), "%s\n", __func__);
|
|
|
|
/* ASSERT: channel is idle */
|
|
if (dma_readl(dw, CH_EN) & dwc->mask) {
|
|
dev_dbg(chan2dev(chan), "DMA channel not idle?\n");
|
|
return -EIO;
|
|
}
|
|
|
|
dma_cookie_init(chan);
|
|
|
|
/*
|
|
* NOTE: some controllers may have additional features that we
|
|
* need to initialize here, like "scatter-gather" (which
|
|
* doesn't mean what you think it means), and status writeback.
|
|
*/
|
|
|
|
spin_lock_irqsave(&dwc->lock, flags);
|
|
i = dwc->descs_allocated;
|
|
while (dwc->descs_allocated < NR_DESCS_PER_CHANNEL) {
|
|
spin_unlock_irqrestore(&dwc->lock, flags);
|
|
|
|
desc = kzalloc(sizeof(struct dw_desc), GFP_KERNEL);
|
|
if (!desc) {
|
|
dev_info(chan2dev(chan),
|
|
"only allocated %d descriptors\n", i);
|
|
spin_lock_irqsave(&dwc->lock, flags);
|
|
break;
|
|
}
|
|
|
|
INIT_LIST_HEAD(&desc->tx_list);
|
|
dma_async_tx_descriptor_init(&desc->txd, chan);
|
|
desc->txd.tx_submit = dwc_tx_submit;
|
|
desc->txd.flags = DMA_CTRL_ACK;
|
|
desc->txd.phys = dma_map_single(chan2parent(chan), &desc->lli,
|
|
sizeof(desc->lli), DMA_TO_DEVICE);
|
|
dwc_desc_put(dwc, desc);
|
|
|
|
spin_lock_irqsave(&dwc->lock, flags);
|
|
i = ++dwc->descs_allocated;
|
|
}
|
|
|
|
spin_unlock_irqrestore(&dwc->lock, flags);
|
|
|
|
dev_dbg(chan2dev(chan), "%s: allocated %d descriptors\n", __func__, i);
|
|
|
|
return i;
|
|
}
|
|
|
|
static void dwc_free_chan_resources(struct dma_chan *chan)
|
|
{
|
|
struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
|
|
struct dw_dma *dw = to_dw_dma(chan->device);
|
|
struct dw_desc *desc, *_desc;
|
|
unsigned long flags;
|
|
LIST_HEAD(list);
|
|
|
|
dev_dbg(chan2dev(chan), "%s: descs allocated=%u\n", __func__,
|
|
dwc->descs_allocated);
|
|
|
|
/* ASSERT: channel is idle */
|
|
BUG_ON(!list_empty(&dwc->active_list));
|
|
BUG_ON(!list_empty(&dwc->queue));
|
|
BUG_ON(dma_readl(to_dw_dma(chan->device), CH_EN) & dwc->mask);
|
|
|
|
spin_lock_irqsave(&dwc->lock, flags);
|
|
list_splice_init(&dwc->free_list, &list);
|
|
dwc->descs_allocated = 0;
|
|
dwc->initialized = false;
|
|
|
|
/* Disable interrupts */
|
|
channel_clear_bit(dw, MASK.XFER, dwc->mask);
|
|
channel_clear_bit(dw, MASK.ERROR, dwc->mask);
|
|
|
|
spin_unlock_irqrestore(&dwc->lock, flags);
|
|
|
|
list_for_each_entry_safe(desc, _desc, &list, desc_node) {
|
|
dev_vdbg(chan2dev(chan), " freeing descriptor %p\n", desc);
|
|
dma_unmap_single(chan2parent(chan), desc->txd.phys,
|
|
sizeof(desc->lli), DMA_TO_DEVICE);
|
|
kfree(desc);
|
|
}
|
|
|
|
dev_vdbg(chan2dev(chan), "%s: done\n", __func__);
|
|
}
|
|
|
|
/* --------------------- Cyclic DMA API extensions -------------------- */
|
|
|
|
/**
|
|
* dw_dma_cyclic_start - start the cyclic DMA transfer
|
|
* @chan: the DMA channel to start
|
|
*
|
|
* Must be called with soft interrupts disabled. Returns zero on success or
|
|
* -errno on failure.
|
|
*/
|
|
int dw_dma_cyclic_start(struct dma_chan *chan)
|
|
{
|
|
struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
|
|
struct dw_dma *dw = to_dw_dma(dwc->chan.device);
|
|
unsigned long flags;
|
|
|
|
if (!test_bit(DW_DMA_IS_CYCLIC, &dwc->flags)) {
|
|
dev_err(chan2dev(&dwc->chan), "missing prep for cyclic DMA\n");
|
|
return -ENODEV;
|
|
}
|
|
|
|
spin_lock_irqsave(&dwc->lock, flags);
|
|
|
|
/* assert channel is idle */
|
|
if (dma_readl(dw, CH_EN) & dwc->mask) {
|
|
dev_err(chan2dev(&dwc->chan),
|
|
"BUG: Attempted to start non-idle channel\n");
|
|
dwc_dump_chan_regs(dwc);
|
|
spin_unlock_irqrestore(&dwc->lock, flags);
|
|
return -EBUSY;
|
|
}
|
|
|
|
dma_writel(dw, CLEAR.ERROR, dwc->mask);
|
|
dma_writel(dw, CLEAR.XFER, dwc->mask);
|
|
|
|
/* setup DMAC channel registers */
|
|
channel_writel(dwc, LLP, dwc->cdesc->desc[0]->txd.phys);
|
|
channel_writel(dwc, CTL_LO, DWC_CTLL_LLP_D_EN | DWC_CTLL_LLP_S_EN);
|
|
channel_writel(dwc, CTL_HI, 0);
|
|
|
|
channel_set_bit(dw, CH_EN, dwc->mask);
|
|
|
|
spin_unlock_irqrestore(&dwc->lock, flags);
|
|
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL(dw_dma_cyclic_start);
|
|
|
|
/**
|
|
* dw_dma_cyclic_stop - stop the cyclic DMA transfer
|
|
* @chan: the DMA channel to stop
|
|
*
|
|
* Must be called with soft interrupts disabled.
|
|
*/
|
|
void dw_dma_cyclic_stop(struct dma_chan *chan)
|
|
{
|
|
struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
|
|
struct dw_dma *dw = to_dw_dma(dwc->chan.device);
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&dwc->lock, flags);
|
|
|
|
dwc_chan_disable(dw, dwc);
|
|
|
|
spin_unlock_irqrestore(&dwc->lock, flags);
|
|
}
|
|
EXPORT_SYMBOL(dw_dma_cyclic_stop);
|
|
|
|
/**
|
|
* dw_dma_cyclic_prep - prepare the cyclic DMA transfer
|
|
* @chan: the DMA channel to prepare
|
|
* @buf_addr: physical DMA address where the buffer starts
|
|
* @buf_len: total number of bytes for the entire buffer
|
|
* @period_len: number of bytes for each period
|
|
* @direction: transfer direction, to or from device
|
|
*
|
|
* Must be called before trying to start the transfer. Returns a valid struct
|
|
* dw_cyclic_desc if successful or an ERR_PTR(-errno) if not successful.
|
|
*/
|
|
struct dw_cyclic_desc *dw_dma_cyclic_prep(struct dma_chan *chan,
|
|
dma_addr_t buf_addr, size_t buf_len, size_t period_len,
|
|
enum dma_transfer_direction direction)
|
|
{
|
|
struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
|
|
struct dma_slave_config *sconfig = &dwc->dma_sconfig;
|
|
struct dw_cyclic_desc *cdesc;
|
|
struct dw_cyclic_desc *retval = NULL;
|
|
struct dw_desc *desc;
|
|
struct dw_desc *last = NULL;
|
|
unsigned long was_cyclic;
|
|
unsigned int reg_width;
|
|
unsigned int periods;
|
|
unsigned int i;
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&dwc->lock, flags);
|
|
if (dwc->nollp) {
|
|
spin_unlock_irqrestore(&dwc->lock, flags);
|
|
dev_dbg(chan2dev(&dwc->chan),
|
|
"channel doesn't support LLP transfers\n");
|
|
return ERR_PTR(-EINVAL);
|
|
}
|
|
|
|
if (!list_empty(&dwc->queue) || !list_empty(&dwc->active_list)) {
|
|
spin_unlock_irqrestore(&dwc->lock, flags);
|
|
dev_dbg(chan2dev(&dwc->chan),
|
|
"queue and/or active list are not empty\n");
|
|
return ERR_PTR(-EBUSY);
|
|
}
|
|
|
|
was_cyclic = test_and_set_bit(DW_DMA_IS_CYCLIC, &dwc->flags);
|
|
spin_unlock_irqrestore(&dwc->lock, flags);
|
|
if (was_cyclic) {
|
|
dev_dbg(chan2dev(&dwc->chan),
|
|
"channel already prepared for cyclic DMA\n");
|
|
return ERR_PTR(-EBUSY);
|
|
}
|
|
|
|
retval = ERR_PTR(-EINVAL);
|
|
|
|
if (direction == DMA_MEM_TO_DEV)
|
|
reg_width = __ffs(sconfig->dst_addr_width);
|
|
else
|
|
reg_width = __ffs(sconfig->src_addr_width);
|
|
|
|
periods = buf_len / period_len;
|
|
|
|
/* Check for too big/unaligned periods and unaligned DMA buffer. */
|
|
if (period_len > (dwc->block_size << reg_width))
|
|
goto out_err;
|
|
if (unlikely(period_len & ((1 << reg_width) - 1)))
|
|
goto out_err;
|
|
if (unlikely(buf_addr & ((1 << reg_width) - 1)))
|
|
goto out_err;
|
|
if (unlikely(!(direction & (DMA_MEM_TO_DEV | DMA_DEV_TO_MEM))))
|
|
goto out_err;
|
|
|
|
retval = ERR_PTR(-ENOMEM);
|
|
|
|
if (periods > NR_DESCS_PER_CHANNEL)
|
|
goto out_err;
|
|
|
|
cdesc = kzalloc(sizeof(struct dw_cyclic_desc), GFP_KERNEL);
|
|
if (!cdesc)
|
|
goto out_err;
|
|
|
|
cdesc->desc = kzalloc(sizeof(struct dw_desc *) * periods, GFP_KERNEL);
|
|
if (!cdesc->desc)
|
|
goto out_err_alloc;
|
|
|
|
for (i = 0; i < periods; i++) {
|
|
desc = dwc_desc_get(dwc);
|
|
if (!desc)
|
|
goto out_err_desc_get;
|
|
|
|
switch (direction) {
|
|
case DMA_MEM_TO_DEV:
|
|
desc->lli.dar = sconfig->dst_addr;
|
|
desc->lli.sar = buf_addr + (period_len * i);
|
|
desc->lli.ctllo = (DWC_DEFAULT_CTLLO(chan)
|
|
| DWC_CTLL_DST_WIDTH(reg_width)
|
|
| DWC_CTLL_SRC_WIDTH(reg_width)
|
|
| DWC_CTLL_DST_FIX
|
|
| DWC_CTLL_SRC_INC
|
|
| DWC_CTLL_INT_EN);
|
|
|
|
desc->lli.ctllo |= sconfig->device_fc ?
|
|
DWC_CTLL_FC(DW_DMA_FC_P_M2P) :
|
|
DWC_CTLL_FC(DW_DMA_FC_D_M2P);
|
|
|
|
break;
|
|
case DMA_DEV_TO_MEM:
|
|
desc->lli.dar = buf_addr + (period_len * i);
|
|
desc->lli.sar = sconfig->src_addr;
|
|
desc->lli.ctllo = (DWC_DEFAULT_CTLLO(chan)
|
|
| DWC_CTLL_SRC_WIDTH(reg_width)
|
|
| DWC_CTLL_DST_WIDTH(reg_width)
|
|
| DWC_CTLL_DST_INC
|
|
| DWC_CTLL_SRC_FIX
|
|
| DWC_CTLL_INT_EN);
|
|
|
|
desc->lli.ctllo |= sconfig->device_fc ?
|
|
DWC_CTLL_FC(DW_DMA_FC_P_P2M) :
|
|
DWC_CTLL_FC(DW_DMA_FC_D_P2M);
|
|
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
|
|
desc->lli.ctlhi = (period_len >> reg_width);
|
|
cdesc->desc[i] = desc;
|
|
|
|
if (last) {
|
|
last->lli.llp = desc->txd.phys;
|
|
dma_sync_single_for_device(chan2parent(chan),
|
|
last->txd.phys, sizeof(last->lli),
|
|
DMA_TO_DEVICE);
|
|
}
|
|
|
|
last = desc;
|
|
}
|
|
|
|
/* lets make a cyclic list */
|
|
last->lli.llp = cdesc->desc[0]->txd.phys;
|
|
dma_sync_single_for_device(chan2parent(chan), last->txd.phys,
|
|
sizeof(last->lli), DMA_TO_DEVICE);
|
|
|
|
dev_dbg(chan2dev(&dwc->chan), "cyclic prepared buf 0x%llx len %zu "
|
|
"period %zu periods %d\n", (unsigned long long)buf_addr,
|
|
buf_len, period_len, periods);
|
|
|
|
cdesc->periods = periods;
|
|
dwc->cdesc = cdesc;
|
|
|
|
return cdesc;
|
|
|
|
out_err_desc_get:
|
|
while (i--)
|
|
dwc_desc_put(dwc, cdesc->desc[i]);
|
|
out_err_alloc:
|
|
kfree(cdesc);
|
|
out_err:
|
|
clear_bit(DW_DMA_IS_CYCLIC, &dwc->flags);
|
|
return (struct dw_cyclic_desc *)retval;
|
|
}
|
|
EXPORT_SYMBOL(dw_dma_cyclic_prep);
|
|
|
|
/**
|
|
* dw_dma_cyclic_free - free a prepared cyclic DMA transfer
|
|
* @chan: the DMA channel to free
|
|
*/
|
|
void dw_dma_cyclic_free(struct dma_chan *chan)
|
|
{
|
|
struct dw_dma_chan *dwc = to_dw_dma_chan(chan);
|
|
struct dw_dma *dw = to_dw_dma(dwc->chan.device);
|
|
struct dw_cyclic_desc *cdesc = dwc->cdesc;
|
|
int i;
|
|
unsigned long flags;
|
|
|
|
dev_dbg(chan2dev(&dwc->chan), "%s\n", __func__);
|
|
|
|
if (!cdesc)
|
|
return;
|
|
|
|
spin_lock_irqsave(&dwc->lock, flags);
|
|
|
|
dwc_chan_disable(dw, dwc);
|
|
|
|
dma_writel(dw, CLEAR.ERROR, dwc->mask);
|
|
dma_writel(dw, CLEAR.XFER, dwc->mask);
|
|
|
|
spin_unlock_irqrestore(&dwc->lock, flags);
|
|
|
|
for (i = 0; i < cdesc->periods; i++)
|
|
dwc_desc_put(dwc, cdesc->desc[i]);
|
|
|
|
kfree(cdesc->desc);
|
|
kfree(cdesc);
|
|
|
|
clear_bit(DW_DMA_IS_CYCLIC, &dwc->flags);
|
|
}
|
|
EXPORT_SYMBOL(dw_dma_cyclic_free);
|
|
|
|
/*----------------------------------------------------------------------*/
|
|
|
|
static void dw_dma_off(struct dw_dma *dw)
|
|
{
|
|
int i;
|
|
|
|
dma_writel(dw, CFG, 0);
|
|
|
|
channel_clear_bit(dw, MASK.XFER, dw->all_chan_mask);
|
|
channel_clear_bit(dw, MASK.SRC_TRAN, dw->all_chan_mask);
|
|
channel_clear_bit(dw, MASK.DST_TRAN, dw->all_chan_mask);
|
|
channel_clear_bit(dw, MASK.ERROR, dw->all_chan_mask);
|
|
|
|
while (dma_readl(dw, CFG) & DW_CFG_DMA_EN)
|
|
cpu_relax();
|
|
|
|
for (i = 0; i < dw->dma.chancnt; i++)
|
|
dw->chan[i].initialized = false;
|
|
}
|
|
|
|
static int dw_probe(struct platform_device *pdev)
|
|
{
|
|
struct dw_dma_platform_data *pdata;
|
|
struct resource *io;
|
|
struct dw_dma *dw;
|
|
size_t size;
|
|
void __iomem *regs;
|
|
bool autocfg;
|
|
unsigned int dw_params;
|
|
unsigned int nr_channels;
|
|
unsigned int max_blk_size = 0;
|
|
int irq;
|
|
int err;
|
|
int i;
|
|
|
|
pdata = dev_get_platdata(&pdev->dev);
|
|
if (!pdata || pdata->nr_channels > DW_DMA_MAX_NR_CHANNELS)
|
|
return -EINVAL;
|
|
|
|
io = platform_get_resource(pdev, IORESOURCE_MEM, 0);
|
|
if (!io)
|
|
return -EINVAL;
|
|
|
|
irq = platform_get_irq(pdev, 0);
|
|
if (irq < 0)
|
|
return irq;
|
|
|
|
regs = devm_request_and_ioremap(&pdev->dev, io);
|
|
if (!regs)
|
|
return -EBUSY;
|
|
|
|
dw_params = dma_read_byaddr(regs, DW_PARAMS);
|
|
autocfg = dw_params >> DW_PARAMS_EN & 0x1;
|
|
|
|
if (autocfg)
|
|
nr_channels = (dw_params >> DW_PARAMS_NR_CHAN & 0x7) + 1;
|
|
else
|
|
nr_channels = pdata->nr_channels;
|
|
|
|
size = sizeof(struct dw_dma) + nr_channels * sizeof(struct dw_dma_chan);
|
|
dw = devm_kzalloc(&pdev->dev, size, GFP_KERNEL);
|
|
if (!dw)
|
|
return -ENOMEM;
|
|
|
|
dw->clk = devm_clk_get(&pdev->dev, "hclk");
|
|
if (IS_ERR(dw->clk))
|
|
return PTR_ERR(dw->clk);
|
|
clk_prepare_enable(dw->clk);
|
|
|
|
dw->regs = regs;
|
|
|
|
/* get hardware configuration parameters */
|
|
if (autocfg) {
|
|
max_blk_size = dma_readl(dw, MAX_BLK_SIZE);
|
|
|
|
dw->nr_masters = (dw_params >> DW_PARAMS_NR_MASTER & 3) + 1;
|
|
for (i = 0; i < dw->nr_masters; i++) {
|
|
dw->data_width[i] =
|
|
(dw_params >> DW_PARAMS_DATA_WIDTH(i) & 3) + 2;
|
|
}
|
|
} else {
|
|
dw->nr_masters = pdata->nr_masters;
|
|
memcpy(dw->data_width, pdata->data_width, 4);
|
|
}
|
|
|
|
/* Calculate all channel mask before DMA setup */
|
|
dw->all_chan_mask = (1 << nr_channels) - 1;
|
|
|
|
/* force dma off, just in case */
|
|
dw_dma_off(dw);
|
|
|
|
/* disable BLOCK interrupts as well */
|
|
channel_clear_bit(dw, MASK.BLOCK, dw->all_chan_mask);
|
|
|
|
err = devm_request_irq(&pdev->dev, irq, dw_dma_interrupt, 0,
|
|
"dw_dmac", dw);
|
|
if (err)
|
|
return err;
|
|
|
|
platform_set_drvdata(pdev, dw);
|
|
|
|
tasklet_init(&dw->tasklet, dw_dma_tasklet, (unsigned long)dw);
|
|
|
|
INIT_LIST_HEAD(&dw->dma.channels);
|
|
for (i = 0; i < nr_channels; i++) {
|
|
struct dw_dma_chan *dwc = &dw->chan[i];
|
|
int r = nr_channels - i - 1;
|
|
|
|
dwc->chan.device = &dw->dma;
|
|
dma_cookie_init(&dwc->chan);
|
|
if (pdata->chan_allocation_order == CHAN_ALLOCATION_ASCENDING)
|
|
list_add_tail(&dwc->chan.device_node,
|
|
&dw->dma.channels);
|
|
else
|
|
list_add(&dwc->chan.device_node, &dw->dma.channels);
|
|
|
|
/* 7 is highest priority & 0 is lowest. */
|
|
if (pdata->chan_priority == CHAN_PRIORITY_ASCENDING)
|
|
dwc->priority = r;
|
|
else
|
|
dwc->priority = i;
|
|
|
|
dwc->ch_regs = &__dw_regs(dw)->CHAN[i];
|
|
spin_lock_init(&dwc->lock);
|
|
dwc->mask = 1 << i;
|
|
|
|
INIT_LIST_HEAD(&dwc->active_list);
|
|
INIT_LIST_HEAD(&dwc->queue);
|
|
INIT_LIST_HEAD(&dwc->free_list);
|
|
|
|
channel_clear_bit(dw, CH_EN, dwc->mask);
|
|
|
|
dwc->dw = dw;
|
|
|
|
/* hardware configuration */
|
|
if (autocfg) {
|
|
unsigned int dwc_params;
|
|
|
|
dwc_params = dma_read_byaddr(regs + r * sizeof(u32),
|
|
DWC_PARAMS);
|
|
|
|
/* Decode maximum block size for given channel. The
|
|
* stored 4 bit value represents blocks from 0x00 for 3
|
|
* up to 0x0a for 4095. */
|
|
dwc->block_size =
|
|
(4 << ((max_blk_size >> 4 * i) & 0xf)) - 1;
|
|
dwc->nollp =
|
|
(dwc_params >> DWC_PARAMS_MBLK_EN & 0x1) == 0;
|
|
} else {
|
|
dwc->block_size = pdata->block_size;
|
|
|
|
/* Check if channel supports multi block transfer */
|
|
channel_writel(dwc, LLP, 0xfffffffc);
|
|
dwc->nollp =
|
|
(channel_readl(dwc, LLP) & 0xfffffffc) == 0;
|
|
channel_writel(dwc, LLP, 0);
|
|
}
|
|
}
|
|
|
|
/* Clear all interrupts on all channels. */
|
|
dma_writel(dw, CLEAR.XFER, dw->all_chan_mask);
|
|
dma_writel(dw, CLEAR.BLOCK, dw->all_chan_mask);
|
|
dma_writel(dw, CLEAR.SRC_TRAN, dw->all_chan_mask);
|
|
dma_writel(dw, CLEAR.DST_TRAN, dw->all_chan_mask);
|
|
dma_writel(dw, CLEAR.ERROR, dw->all_chan_mask);
|
|
|
|
dma_cap_set(DMA_MEMCPY, dw->dma.cap_mask);
|
|
dma_cap_set(DMA_SLAVE, dw->dma.cap_mask);
|
|
if (pdata->is_private)
|
|
dma_cap_set(DMA_PRIVATE, dw->dma.cap_mask);
|
|
dw->dma.dev = &pdev->dev;
|
|
dw->dma.device_alloc_chan_resources = dwc_alloc_chan_resources;
|
|
dw->dma.device_free_chan_resources = dwc_free_chan_resources;
|
|
|
|
dw->dma.device_prep_dma_memcpy = dwc_prep_dma_memcpy;
|
|
|
|
dw->dma.device_prep_slave_sg = dwc_prep_slave_sg;
|
|
dw->dma.device_control = dwc_control;
|
|
|
|
dw->dma.device_tx_status = dwc_tx_status;
|
|
dw->dma.device_issue_pending = dwc_issue_pending;
|
|
|
|
dma_writel(dw, CFG, DW_CFG_DMA_EN);
|
|
|
|
printk(KERN_INFO "%s: DesignWare DMA Controller, %d channels\n",
|
|
dev_name(&pdev->dev), nr_channels);
|
|
|
|
dma_async_device_register(&dw->dma);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int dw_remove(struct platform_device *pdev)
|
|
{
|
|
struct dw_dma *dw = platform_get_drvdata(pdev);
|
|
struct dw_dma_chan *dwc, *_dwc;
|
|
|
|
dw_dma_off(dw);
|
|
dma_async_device_unregister(&dw->dma);
|
|
|
|
tasklet_kill(&dw->tasklet);
|
|
|
|
list_for_each_entry_safe(dwc, _dwc, &dw->dma.channels,
|
|
chan.device_node) {
|
|
list_del(&dwc->chan.device_node);
|
|
channel_clear_bit(dw, CH_EN, dwc->mask);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void dw_shutdown(struct platform_device *pdev)
|
|
{
|
|
struct dw_dma *dw = platform_get_drvdata(pdev);
|
|
|
|
dw_dma_off(platform_get_drvdata(pdev));
|
|
clk_disable_unprepare(dw->clk);
|
|
}
|
|
|
|
static int dw_suspend_noirq(struct device *dev)
|
|
{
|
|
struct platform_device *pdev = to_platform_device(dev);
|
|
struct dw_dma *dw = platform_get_drvdata(pdev);
|
|
|
|
dw_dma_off(platform_get_drvdata(pdev));
|
|
clk_disable_unprepare(dw->clk);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int dw_resume_noirq(struct device *dev)
|
|
{
|
|
struct platform_device *pdev = to_platform_device(dev);
|
|
struct dw_dma *dw = platform_get_drvdata(pdev);
|
|
|
|
clk_prepare_enable(dw->clk);
|
|
dma_writel(dw, CFG, DW_CFG_DMA_EN);
|
|
return 0;
|
|
}
|
|
|
|
static const struct dev_pm_ops dw_dev_pm_ops = {
|
|
.suspend_noirq = dw_suspend_noirq,
|
|
.resume_noirq = dw_resume_noirq,
|
|
.freeze_noirq = dw_suspend_noirq,
|
|
.thaw_noirq = dw_resume_noirq,
|
|
.restore_noirq = dw_resume_noirq,
|
|
.poweroff_noirq = dw_suspend_noirq,
|
|
};
|
|
|
|
#ifdef CONFIG_OF
|
|
static const struct of_device_id dw_dma_id_table[] = {
|
|
{ .compatible = "snps,dma-spear1340" },
|
|
{}
|
|
};
|
|
MODULE_DEVICE_TABLE(of, dw_dma_id_table);
|
|
#endif
|
|
|
|
static struct platform_driver dw_driver = {
|
|
.remove = dw_remove,
|
|
.shutdown = dw_shutdown,
|
|
.driver = {
|
|
.name = "dw_dmac",
|
|
.pm = &dw_dev_pm_ops,
|
|
.of_match_table = of_match_ptr(dw_dma_id_table),
|
|
},
|
|
};
|
|
|
|
static int __init dw_init(void)
|
|
{
|
|
return platform_driver_probe(&dw_driver, dw_probe);
|
|
}
|
|
subsys_initcall(dw_init);
|
|
|
|
static void __exit dw_exit(void)
|
|
{
|
|
platform_driver_unregister(&dw_driver);
|
|
}
|
|
module_exit(dw_exit);
|
|
|
|
MODULE_LICENSE("GPL v2");
|
|
MODULE_DESCRIPTION("Synopsys DesignWare DMA Controller driver");
|
|
MODULE_AUTHOR("Haavard Skinnemoen (Atmel)");
|
|
MODULE_AUTHOR("Viresh Kumar <viresh.linux@gmail.com>");
|