blob: 629be353c63a6b5091ca1ed5cb7d7f620a03c0b0 [file] [log] [blame]
/*
* drivers/dma/imx-dma.c
*
* This file contains a driver for the Freescale i.MX DMA engine
* found on i.MX1/21/27
*
* Copyright 2010 Sascha Hauer, Pengutronix <s.hauer@pengutronix.de>
* Copyright 2012 Javier Martin, Vista Silicon <javier.martin@vista-silicon.com>
*
* The code contained herein is licensed under the GNU General Public
* License. You may obtain a copy of the GNU General Public License
* Version 2 or later at the following locations:
*
* http://www.opensource.org/licenses/gpl-license.html
* http://www.gnu.org/copyleft/gpl.html
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/types.h>
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/spinlock.h>
#include <linux/device.h>
#include <linux/dma-mapping.h>
#include <linux/slab.h>
#include <linux/platform_device.h>
#include <linux/clk.h>
#include <linux/dmaengine.h>
#include <linux/module.h>
#include <asm/irq.h>
#include <mach/dma.h>
#include <mach/hardware.h>
#include "dmaengine.h"
#define IMXDMA_MAX_CHAN_DESCRIPTORS 16
#define IMX_DMA_CHANNELS 16
#define IMX_DMA_LENGTH_LOOP ((unsigned int)-1)
#define IMX_DMA_MEMSIZE_32 (0 << 4)
#define IMX_DMA_MEMSIZE_8 (1 << 4)
#define IMX_DMA_MEMSIZE_16 (2 << 4)
#define IMX_DMA_TYPE_LINEAR (0 << 10)
#define IMX_DMA_TYPE_2D (1 << 10)
#define IMX_DMA_TYPE_FIFO (2 << 10)
#define IMX_DMA_ERR_BURST (1 << 0)
#define IMX_DMA_ERR_REQUEST (1 << 1)
#define IMX_DMA_ERR_TRANSFER (1 << 2)
#define IMX_DMA_ERR_BUFFER (1 << 3)
#define IMX_DMA_ERR_TIMEOUT (1 << 4)
#define DMA_DCR 0x00 /* Control Register */
#define DMA_DISR 0x04 /* Interrupt status Register */
#define DMA_DIMR 0x08 /* Interrupt mask Register */
#define DMA_DBTOSR 0x0c /* Burst timeout status Register */
#define DMA_DRTOSR 0x10 /* Request timeout Register */
#define DMA_DSESR 0x14 /* Transfer Error Status Register */
#define DMA_DBOSR 0x18 /* Buffer overflow status Register */
#define DMA_DBTOCR 0x1c /* Burst timeout control Register */
#define DMA_WSRA 0x40 /* W-Size Register A */
#define DMA_XSRA 0x44 /* X-Size Register A */
#define DMA_YSRA 0x48 /* Y-Size Register A */
#define DMA_WSRB 0x4c /* W-Size Register B */
#define DMA_XSRB 0x50 /* X-Size Register B */
#define DMA_YSRB 0x54 /* Y-Size Register B */
#define DMA_SAR(x) (0x80 + ((x) << 6)) /* Source Address Registers */
#define DMA_DAR(x) (0x84 + ((x) << 6)) /* Destination Address Registers */
#define DMA_CNTR(x) (0x88 + ((x) << 6)) /* Count Registers */
#define DMA_CCR(x) (0x8c + ((x) << 6)) /* Control Registers */
#define DMA_RSSR(x) (0x90 + ((x) << 6)) /* Request source select Registers */
#define DMA_BLR(x) (0x94 + ((x) << 6)) /* Burst length Registers */
#define DMA_RTOR(x) (0x98 + ((x) << 6)) /* Request timeout Registers */
#define DMA_BUCR(x) (0x98 + ((x) << 6)) /* Bus Utilization Registers */
#define DMA_CCNR(x) (0x9C + ((x) << 6)) /* Channel counter Registers */
#define DCR_DRST (1<<1)
#define DCR_DEN (1<<0)
#define DBTOCR_EN (1<<15)
#define DBTOCR_CNT(x) ((x) & 0x7fff)
#define CNTR_CNT(x) ((x) & 0xffffff)
#define CCR_ACRPT (1<<14)
#define CCR_DMOD_LINEAR (0x0 << 12)
#define CCR_DMOD_2D (0x1 << 12)
#define CCR_DMOD_FIFO (0x2 << 12)
#define CCR_DMOD_EOBFIFO (0x3 << 12)
#define CCR_SMOD_LINEAR (0x0 << 10)
#define CCR_SMOD_2D (0x1 << 10)
#define CCR_SMOD_FIFO (0x2 << 10)
#define CCR_SMOD_EOBFIFO (0x3 << 10)
#define CCR_MDIR_DEC (1<<9)
#define CCR_MSEL_B (1<<8)
#define CCR_DSIZ_32 (0x0 << 6)
#define CCR_DSIZ_8 (0x1 << 6)
#define CCR_DSIZ_16 (0x2 << 6)
#define CCR_SSIZ_32 (0x0 << 4)
#define CCR_SSIZ_8 (0x1 << 4)
#define CCR_SSIZ_16 (0x2 << 4)
#define CCR_REN (1<<3)
#define CCR_RPT (1<<2)
#define CCR_FRC (1<<1)
#define CCR_CEN (1<<0)
#define RTOR_EN (1<<15)
#define RTOR_CLK (1<<14)
#define RTOR_PSC (1<<13)
enum imxdma_prep_type {
IMXDMA_DESC_MEMCPY,
IMXDMA_DESC_INTERLEAVED,
IMXDMA_DESC_SLAVE_SG,
IMXDMA_DESC_CYCLIC,
};
struct imxdma_desc {
struct list_head node;
struct dma_async_tx_descriptor desc;
enum dma_status status;
dma_addr_t src;
dma_addr_t dest;
size_t len;
enum dma_transfer_direction direction;
enum imxdma_prep_type type;
/* For memcpy and interleaved */
unsigned int config_port;
unsigned int config_mem;
/* For interleaved transfers */
unsigned int x;
unsigned int y;
unsigned int w;
/* For slave sg and cyclic */
struct scatterlist *sg;
unsigned int sgcount;
};
struct imxdma_channel {
int hw_chaining;
struct timer_list watchdog;
struct imxdma_engine *imxdma;
unsigned int channel;
struct tasklet_struct dma_tasklet;
struct list_head ld_free;
struct list_head ld_queue;
struct list_head ld_active;
int descs_allocated;
enum dma_slave_buswidth word_size;
dma_addr_t per_address;
u32 watermark_level;
struct dma_chan chan;
spinlock_t lock;
struct dma_async_tx_descriptor desc;
enum dma_status status;
int dma_request;
struct scatterlist *sg_list;
u32 ccr_from_device;
u32 ccr_to_device;
};
struct imxdma_engine {
struct device *dev;
struct device_dma_parameters dma_parms;
struct dma_device dma_device;
struct imxdma_channel channel[IMX_DMA_CHANNELS];
};
static struct imxdma_channel *to_imxdma_chan(struct dma_chan *chan)
{
return container_of(chan, struct imxdma_channel, chan);
}
static inline bool imxdma_chan_is_doing_cyclic(struct imxdma_channel *imxdmac)
{
struct imxdma_desc *desc;
if (!list_empty(&imxdmac->ld_active)) {
desc = list_first_entry(&imxdmac->ld_active, struct imxdma_desc,
node);
if (desc->type == IMXDMA_DESC_CYCLIC)
return true;
}
return false;
}
/* TODO: put this inside any struct */
static void __iomem *imx_dmav1_baseaddr;
static struct clk *dma_clk;
static void imx_dmav1_writel(unsigned val, unsigned offset)
{
__raw_writel(val, imx_dmav1_baseaddr + offset);
}
static unsigned imx_dmav1_readl(unsigned offset)
{
return __raw_readl(imx_dmav1_baseaddr + offset);
}
static int imxdma_hw_chain(struct imxdma_channel *imxdmac)
{
if (cpu_is_mx27())
return imxdmac->hw_chaining;
else
return 0;
}
/*
* imxdma_sg_next - prepare next chunk for scatter-gather DMA emulation
*/
static inline int imxdma_sg_next(struct imxdma_desc *d, struct scatterlist *sg)
{
struct imxdma_channel *imxdmac = to_imxdma_chan(d->desc.chan);
unsigned long now;
now = min(d->len, sg->length);
if (d->len != IMX_DMA_LENGTH_LOOP)
d->len -= now;
if (d->direction == DMA_DEV_TO_MEM)
imx_dmav1_writel(sg->dma_address, DMA_DAR(imxdmac->channel));
else
imx_dmav1_writel(sg->dma_address, DMA_SAR(imxdmac->channel));
imx_dmav1_writel(now, DMA_CNTR(imxdmac->channel));
pr_debug("imxdma%d: next sg chunk dst 0x%08x, src 0x%08x, "
"size 0x%08x\n", imxdmac->channel,
imx_dmav1_readl(DMA_DAR(imxdmac->channel)),
imx_dmav1_readl(DMA_SAR(imxdmac->channel)),
imx_dmav1_readl(DMA_CNTR(imxdmac->channel)));
return now;
}
static void imxdma_enable_hw(struct imxdma_desc *d)
{
struct imxdma_channel *imxdmac = to_imxdma_chan(d->desc.chan);
int channel = imxdmac->channel;
unsigned long flags;
pr_debug("imxdma%d: imx_dma_enable\n", channel);
local_irq_save(flags);
imx_dmav1_writel(1 << channel, DMA_DISR);
imx_dmav1_writel(imx_dmav1_readl(DMA_DIMR) & ~(1 << channel), DMA_DIMR);
imx_dmav1_writel(imx_dmav1_readl(DMA_CCR(channel)) | CCR_CEN |
CCR_ACRPT, DMA_CCR(channel));
if ((cpu_is_mx21() || cpu_is_mx27()) &&
d->sg && imxdma_hw_chain(imxdmac)) {
d->sg = sg_next(d->sg);
if (d->sg) {
u32 tmp;
imxdma_sg_next(d, d->sg);
tmp = imx_dmav1_readl(DMA_CCR(channel));
imx_dmav1_writel(tmp | CCR_RPT | CCR_ACRPT,
DMA_CCR(channel));
}
}
local_irq_restore(flags);
}
static void imxdma_disable_hw(struct imxdma_channel *imxdmac)
{
int channel = imxdmac->channel;
unsigned long flags;
pr_debug("imxdma%d: imx_dma_disable\n", channel);
if (imxdma_hw_chain(imxdmac))
del_timer(&imxdmac->watchdog);
local_irq_save(flags);
imx_dmav1_writel(imx_dmav1_readl(DMA_DIMR) | (1 << channel), DMA_DIMR);
imx_dmav1_writel(imx_dmav1_readl(DMA_CCR(channel)) & ~CCR_CEN,
DMA_CCR(channel));
imx_dmav1_writel(1 << channel, DMA_DISR);
local_irq_restore(flags);
}
static void imxdma_watchdog(unsigned long data)
{
struct imxdma_channel *imxdmac = (struct imxdma_channel *)data;
int channel = imxdmac->channel;
imx_dmav1_writel(0, DMA_CCR(channel));
/* Tasklet watchdog error handler */
tasklet_schedule(&imxdmac->dma_tasklet);
pr_debug("imxdma%d: watchdog timeout!\n", imxdmac->channel);
}
static irqreturn_t imxdma_err_handler(int irq, void *dev_id)
{
struct imxdma_engine *imxdma = dev_id;
unsigned int err_mask;
int i, disr;
int errcode;
disr = imx_dmav1_readl(DMA_DISR);
err_mask = imx_dmav1_readl(DMA_DBTOSR) |
imx_dmav1_readl(DMA_DRTOSR) |
imx_dmav1_readl(DMA_DSESR) |
imx_dmav1_readl(DMA_DBOSR);
if (!err_mask)
return IRQ_HANDLED;
imx_dmav1_writel(disr & err_mask, DMA_DISR);
for (i = 0; i < IMX_DMA_CHANNELS; i++) {
if (!(err_mask & (1 << i)))
continue;
errcode = 0;
if (imx_dmav1_readl(DMA_DBTOSR) & (1 << i)) {
imx_dmav1_writel(1 << i, DMA_DBTOSR);
errcode |= IMX_DMA_ERR_BURST;
}
if (imx_dmav1_readl(DMA_DRTOSR) & (1 << i)) {
imx_dmav1_writel(1 << i, DMA_DRTOSR);
errcode |= IMX_DMA_ERR_REQUEST;
}
if (imx_dmav1_readl(DMA_DSESR) & (1 << i)) {
imx_dmav1_writel(1 << i, DMA_DSESR);
errcode |= IMX_DMA_ERR_TRANSFER;
}
if (imx_dmav1_readl(DMA_DBOSR) & (1 << i)) {
imx_dmav1_writel(1 << i, DMA_DBOSR);
errcode |= IMX_DMA_ERR_BUFFER;
}
/* Tasklet error handler */
tasklet_schedule(&imxdma->channel[i].dma_tasklet);
printk(KERN_WARNING
"DMA timeout on channel %d -%s%s%s%s\n", i,
errcode & IMX_DMA_ERR_BURST ? " burst" : "",
errcode & IMX_DMA_ERR_REQUEST ? " request" : "",
errcode & IMX_DMA_ERR_TRANSFER ? " transfer" : "",
errcode & IMX_DMA_ERR_BUFFER ? " buffer" : "");
}
return IRQ_HANDLED;
}
static void dma_irq_handle_channel(struct imxdma_channel *imxdmac)
{
int chno = imxdmac->channel;
struct imxdma_desc *desc;
spin_lock(&imxdmac->lock);
if (list_empty(&imxdmac->ld_active)) {
spin_unlock(&imxdmac->lock);
goto out;
}
desc = list_first_entry(&imxdmac->ld_active,
struct imxdma_desc,
node);
spin_unlock(&imxdmac->lock);
if (desc->sg) {
u32 tmp;
desc->sg = sg_next(desc->sg);
if (desc->sg) {
imxdma_sg_next(desc, desc->sg);
tmp = imx_dmav1_readl(DMA_CCR(chno));
if (imxdma_hw_chain(imxdmac)) {
/* FIXME: The timeout should probably be
* configurable
*/
mod_timer(&imxdmac->watchdog,
jiffies + msecs_to_jiffies(500));
tmp |= CCR_CEN | CCR_RPT | CCR_ACRPT;
imx_dmav1_writel(tmp, DMA_CCR(chno));
} else {
imx_dmav1_writel(tmp & ~CCR_CEN, DMA_CCR(chno));
tmp |= CCR_CEN;
}
imx_dmav1_writel(tmp, DMA_CCR(chno));
if (imxdma_chan_is_doing_cyclic(imxdmac))
/* Tasklet progression */
tasklet_schedule(&imxdmac->dma_tasklet);
return;
}
if (imxdma_hw_chain(imxdmac)) {
del_timer(&imxdmac->watchdog);
return;
}
}
out:
imx_dmav1_writel(0, DMA_CCR(chno));
/* Tasklet irq */
tasklet_schedule(&imxdmac->dma_tasklet);
}
static irqreturn_t dma_irq_handler(int irq, void *dev_id)
{
struct imxdma_engine *imxdma = dev_id;
int i, disr;
if (cpu_is_mx21() || cpu_is_mx27())
imxdma_err_handler(irq, dev_id);
disr = imx_dmav1_readl(DMA_DISR);
pr_debug("imxdma: dma_irq_handler called, disr=0x%08x\n",
disr);
imx_dmav1_writel(disr, DMA_DISR);
for (i = 0; i < IMX_DMA_CHANNELS; i++) {
if (disr & (1 << i))
dma_irq_handle_channel(&imxdma->channel[i]);
}
return IRQ_HANDLED;
}
static int imxdma_xfer_desc(struct imxdma_desc *d)
{
struct imxdma_channel *imxdmac = to_imxdma_chan(d->desc.chan);
struct imxdma_engine *imxdma = imxdmac->imxdma;
/* Configure and enable */
switch (d->type) {
case IMXDMA_DESC_MEMCPY:
imx_dmav1_writel(d->src, DMA_SAR(imxdmac->channel));
imx_dmav1_writel(d->dest, DMA_DAR(imxdmac->channel));
imx_dmav1_writel(d->config_mem | (d->config_port << 2),
DMA_CCR(imxdmac->channel));
imx_dmav1_writel(d->len, DMA_CNTR(imxdmac->channel));
dev_dbg(imxdma->dev, "%s channel: %d dest=0x%08x src=0x%08x "
"dma_length=%d\n", __func__, imxdmac->channel,
d->dest, d->src, d->len);
break;
/* Cyclic transfer is the same as slave_sg with special sg configuration. */
case IMXDMA_DESC_CYCLIC:
case IMXDMA_DESC_SLAVE_SG:
if (d->direction == DMA_DEV_TO_MEM) {
imx_dmav1_writel(imxdmac->per_address,
DMA_SAR(imxdmac->channel));
imx_dmav1_writel(imxdmac->ccr_from_device,
DMA_CCR(imxdmac->channel));
dev_dbg(imxdma->dev, "%s channel: %d sg=%p sgcount=%d "
"total length=%d dev_addr=0x%08x (dev2mem)\n",
__func__, imxdmac->channel, d->sg, d->sgcount,
d->len, imxdmac->per_address);
} else if (d->direction == DMA_MEM_TO_DEV) {
imx_dmav1_writel(imxdmac->per_address,
DMA_DAR(imxdmac->channel));
imx_dmav1_writel(imxdmac->ccr_to_device,
DMA_CCR(imxdmac->channel));
dev_dbg(imxdma->dev, "%s channel: %d sg=%p sgcount=%d "
"total length=%d dev_addr=0x%08x (mem2dev)\n",
__func__, imxdmac->channel, d->sg, d->sgcount,
d->len, imxdmac->per_address);
} else {
dev_err(imxdma->dev, "%s channel: %d bad dma mode\n",
__func__, imxdmac->channel);
return -EINVAL;
}
imxdma_sg_next(d, d->sg);
break;
default:
return -EINVAL;
}
imxdma_enable_hw(d);
return 0;
}
static void imxdma_tasklet(unsigned long data)
{
struct imxdma_channel *imxdmac = (void *)data;
struct imxdma_engine *imxdma = imxdmac->imxdma;
struct imxdma_desc *desc;
spin_lock(&imxdmac->lock);
if (list_empty(&imxdmac->ld_active)) {
/* Someone might have called terminate all */
goto out;
}
desc = list_first_entry(&imxdmac->ld_active, struct imxdma_desc, node);
if (desc->desc.callback)
desc->desc.callback(desc->desc.callback_param);
dma_cookie_complete(&desc->desc);
/* If we are dealing with a cyclic descriptor keep it on ld_active */
if (imxdma_chan_is_doing_cyclic(imxdmac))
goto out;
list_move_tail(imxdmac->ld_active.next, &imxdmac->ld_free);
if (!list_empty(&imxdmac->ld_queue)) {
desc = list_first_entry(&imxdmac->ld_queue, struct imxdma_desc,
node);
list_move_tail(imxdmac->ld_queue.next, &imxdmac->ld_active);
if (imxdma_xfer_desc(desc) < 0)
dev_warn(imxdma->dev, "%s: channel: %d couldn't xfer desc\n",
__func__, imxdmac->channel);
}
out:
spin_unlock(&imxdmac->lock);
}
static int imxdma_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
unsigned long arg)
{
struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
struct dma_slave_config *dmaengine_cfg = (void *)arg;
unsigned long flags;
unsigned int mode = 0;
switch (cmd) {
case DMA_TERMINATE_ALL:
imxdma_disable_hw(imxdmac);
spin_lock_irqsave(&imxdmac->lock, flags);
list_splice_tail_init(&imxdmac->ld_active, &imxdmac->ld_free);
list_splice_tail_init(&imxdmac->ld_queue, &imxdmac->ld_free);
spin_unlock_irqrestore(&imxdmac->lock, flags);
return 0;
case DMA_SLAVE_CONFIG:
if (dmaengine_cfg->direction == DMA_DEV_TO_MEM) {
imxdmac->per_address = dmaengine_cfg->src_addr;
imxdmac->watermark_level = dmaengine_cfg->src_maxburst;
imxdmac->word_size = dmaengine_cfg->src_addr_width;
} else {
imxdmac->per_address = dmaengine_cfg->dst_addr;
imxdmac->watermark_level = dmaengine_cfg->dst_maxburst;
imxdmac->word_size = dmaengine_cfg->dst_addr_width;
}
switch (imxdmac->word_size) {
case DMA_SLAVE_BUSWIDTH_1_BYTE:
mode = IMX_DMA_MEMSIZE_8;
break;
case DMA_SLAVE_BUSWIDTH_2_BYTES:
mode = IMX_DMA_MEMSIZE_16;
break;
default:
case DMA_SLAVE_BUSWIDTH_4_BYTES:
mode = IMX_DMA_MEMSIZE_32;
break;
}
imxdmac->hw_chaining = 1;
if (!imxdma_hw_chain(imxdmac))
return -EINVAL;
imxdmac->ccr_from_device = (mode | IMX_DMA_TYPE_FIFO) |
((IMX_DMA_MEMSIZE_32 | IMX_DMA_TYPE_LINEAR) << 2) |
CCR_REN;
imxdmac->ccr_to_device =
(IMX_DMA_MEMSIZE_32 | IMX_DMA_TYPE_LINEAR) |
((mode | IMX_DMA_TYPE_FIFO) << 2) | CCR_REN;
imx_dmav1_writel(imxdmac->dma_request,
DMA_RSSR(imxdmac->channel));
/* Set burst length */
imx_dmav1_writel(imxdmac->watermark_level * imxdmac->word_size,
DMA_BLR(imxdmac->channel));
return 0;
default:
return -ENOSYS;
}
return -EINVAL;
}
static enum dma_status imxdma_tx_status(struct dma_chan *chan,
dma_cookie_t cookie,
struct dma_tx_state *txstate)
{
return dma_cookie_status(chan, cookie, txstate);
}
static dma_cookie_t imxdma_tx_submit(struct dma_async_tx_descriptor *tx)
{
struct imxdma_channel *imxdmac = to_imxdma_chan(tx->chan);
dma_cookie_t cookie;
unsigned long flags;
spin_lock_irqsave(&imxdmac->lock, flags);
cookie = dma_cookie_assign(tx);
spin_unlock_irqrestore(&imxdmac->lock, flags);
return cookie;
}
static int imxdma_alloc_chan_resources(struct dma_chan *chan)
{
struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
struct imx_dma_data *data = chan->private;
if (data != NULL)
imxdmac->dma_request = data->dma_request;
while (imxdmac->descs_allocated < IMXDMA_MAX_CHAN_DESCRIPTORS) {
struct imxdma_desc *desc;
desc = kzalloc(sizeof(*desc), GFP_KERNEL);
if (!desc)
break;
__memzero(&desc->desc, sizeof(struct dma_async_tx_descriptor));
dma_async_tx_descriptor_init(&desc->desc, chan);
desc->desc.tx_submit = imxdma_tx_submit;
/* txd.flags will be overwritten in prep funcs */
desc->desc.flags = DMA_CTRL_ACK;
desc->status = DMA_SUCCESS;
list_add_tail(&desc->node, &imxdmac->ld_free);
imxdmac->descs_allocated++;
}
if (!imxdmac->descs_allocated)
return -ENOMEM;
return imxdmac->descs_allocated;
}
static void imxdma_free_chan_resources(struct dma_chan *chan)
{
struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
struct imxdma_desc *desc, *_desc;
unsigned long flags;
spin_lock_irqsave(&imxdmac->lock, flags);
imxdma_disable_hw(imxdmac);
list_splice_tail_init(&imxdmac->ld_active, &imxdmac->ld_free);
list_splice_tail_init(&imxdmac->ld_queue, &imxdmac->ld_free);
spin_unlock_irqrestore(&imxdmac->lock, flags);
list_for_each_entry_safe(desc, _desc, &imxdmac->ld_free, node) {
kfree(desc);
imxdmac->descs_allocated--;
}
INIT_LIST_HEAD(&imxdmac->ld_free);
if (imxdmac->sg_list) {
kfree(imxdmac->sg_list);
imxdmac->sg_list = NULL;
}
}
static struct dma_async_tx_descriptor *imxdma_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 imxdma_channel *imxdmac = to_imxdma_chan(chan);
struct scatterlist *sg;
int i, dma_length = 0;
struct imxdma_desc *desc;
if (list_empty(&imxdmac->ld_free) ||
imxdma_chan_is_doing_cyclic(imxdmac))
return NULL;
desc = list_first_entry(&imxdmac->ld_free, struct imxdma_desc, node);
for_each_sg(sgl, sg, sg_len, i) {
dma_length += sg->length;
}
switch (imxdmac->word_size) {
case DMA_SLAVE_BUSWIDTH_4_BYTES:
if (sgl->length & 3 || sgl->dma_address & 3)
return NULL;
break;
case DMA_SLAVE_BUSWIDTH_2_BYTES:
if (sgl->length & 1 || sgl->dma_address & 1)
return NULL;
break;
case DMA_SLAVE_BUSWIDTH_1_BYTE:
break;
default:
return NULL;
}
desc->type = IMXDMA_DESC_SLAVE_SG;
desc->sg = sgl;
desc->sgcount = sg_len;
desc->len = dma_length;
desc->direction = direction;
if (direction == DMA_DEV_TO_MEM) {
desc->src = imxdmac->per_address;
} else {
desc->dest = imxdmac->per_address;
}
desc->desc.callback = NULL;
desc->desc.callback_param = NULL;
return &desc->desc;
}
static struct dma_async_tx_descriptor *imxdma_prep_dma_cyclic(
struct dma_chan *chan, dma_addr_t dma_addr, size_t buf_len,
size_t period_len, enum dma_transfer_direction direction,
void *context)
{
struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
struct imxdma_engine *imxdma = imxdmac->imxdma;
struct imxdma_desc *desc;
int i;
unsigned int periods = buf_len / period_len;
dev_dbg(imxdma->dev, "%s channel: %d buf_len=%d period_len=%d\n",
__func__, imxdmac->channel, buf_len, period_len);
if (list_empty(&imxdmac->ld_free) ||
imxdma_chan_is_doing_cyclic(imxdmac))
return NULL;
desc = list_first_entry(&imxdmac->ld_free, struct imxdma_desc, node);
if (imxdmac->sg_list)
kfree(imxdmac->sg_list);
imxdmac->sg_list = kcalloc(periods + 1,
sizeof(struct scatterlist), GFP_KERNEL);
if (!imxdmac->sg_list)
return NULL;
sg_init_table(imxdmac->sg_list, periods);
for (i = 0; i < periods; i++) {
imxdmac->sg_list[i].page_link = 0;
imxdmac->sg_list[i].offset = 0;
imxdmac->sg_list[i].dma_address = dma_addr;
imxdmac->sg_list[i].length = period_len;
dma_addr += period_len;
}
/* close the loop */
imxdmac->sg_list[periods].offset = 0;
imxdmac->sg_list[periods].length = 0;
imxdmac->sg_list[periods].page_link =
((unsigned long)imxdmac->sg_list | 0x01) & ~0x02;
desc->type = IMXDMA_DESC_CYCLIC;
desc->sg = imxdmac->sg_list;
desc->sgcount = periods;
desc->len = IMX_DMA_LENGTH_LOOP;
desc->direction = direction;
if (direction == DMA_DEV_TO_MEM) {
desc->src = imxdmac->per_address;
} else {
desc->dest = imxdmac->per_address;
}
desc->desc.callback = NULL;
desc->desc.callback_param = NULL;
return &desc->desc;
}
static struct dma_async_tx_descriptor *imxdma_prep_dma_memcpy(
struct dma_chan *chan, dma_addr_t dest,
dma_addr_t src, size_t len, unsigned long flags)
{
struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
struct imxdma_engine *imxdma = imxdmac->imxdma;
struct imxdma_desc *desc;
dev_dbg(imxdma->dev, "%s channel: %d src=0x%x dst=0x%x len=%d\n",
__func__, imxdmac->channel, src, dest, len);
if (list_empty(&imxdmac->ld_free) ||
imxdma_chan_is_doing_cyclic(imxdmac))
return NULL;
desc = list_first_entry(&imxdmac->ld_free, struct imxdma_desc, node);
desc->type = IMXDMA_DESC_MEMCPY;
desc->src = src;
desc->dest = dest;
desc->len = len;
desc->direction = DMA_MEM_TO_MEM;
desc->config_port = IMX_DMA_MEMSIZE_32 | IMX_DMA_TYPE_LINEAR;
desc->config_mem = IMX_DMA_MEMSIZE_32 | IMX_DMA_TYPE_LINEAR;
desc->desc.callback = NULL;
desc->desc.callback_param = NULL;
return &desc->desc;
}
static void imxdma_issue_pending(struct dma_chan *chan)
{
struct imxdma_channel *imxdmac = to_imxdma_chan(chan);
struct imxdma_engine *imxdma = imxdmac->imxdma;
struct imxdma_desc *desc;
unsigned long flags;
spin_lock_irqsave(&imxdmac->lock, flags);
if (list_empty(&imxdmac->ld_active) &&
!list_empty(&imxdmac->ld_queue)) {
desc = list_first_entry(&imxdmac->ld_queue,
struct imxdma_desc, node);
if (imxdma_xfer_desc(desc) < 0) {
dev_warn(imxdma->dev,
"%s: channel: %d couldn't issue DMA xfer\n",
__func__, imxdmac->channel);
} else {
list_move_tail(imxdmac->ld_queue.next,
&imxdmac->ld_active);
}
}
spin_unlock_irqrestore(&imxdmac->lock, flags);
}
static int __init imxdma_probe(struct platform_device *pdev)
{
struct imxdma_engine *imxdma;
int ret, i;
if (cpu_is_mx1())
imx_dmav1_baseaddr = MX1_IO_ADDRESS(MX1_DMA_BASE_ADDR);
else if (cpu_is_mx21())
imx_dmav1_baseaddr = MX21_IO_ADDRESS(MX21_DMA_BASE_ADDR);
else if (cpu_is_mx27())
imx_dmav1_baseaddr = MX27_IO_ADDRESS(MX27_DMA_BASE_ADDR);
else
return 0;
dma_clk = clk_get(NULL, "dma");
if (IS_ERR(dma_clk))
return PTR_ERR(dma_clk);
clk_enable(dma_clk);
/* reset DMA module */
imx_dmav1_writel(DCR_DRST, DMA_DCR);
if (cpu_is_mx1()) {
ret = request_irq(MX1_DMA_INT, dma_irq_handler, 0, "DMA", imxdma);
if (ret) {
pr_crit("Can't register IRQ for DMA\n");
return ret;
}
ret = request_irq(MX1_DMA_ERR, imxdma_err_handler, 0, "DMA", imxdma);
if (ret) {
pr_crit("Can't register ERRIRQ for DMA\n");
free_irq(MX1_DMA_INT, NULL);
return ret;
}
}
/* enable DMA module */
imx_dmav1_writel(DCR_DEN, DMA_DCR);
/* clear all interrupts */
imx_dmav1_writel((1 << IMX_DMA_CHANNELS) - 1, DMA_DISR);
/* disable interrupts */
imx_dmav1_writel((1 << IMX_DMA_CHANNELS) - 1, DMA_DIMR);
imxdma = kzalloc(sizeof(*imxdma), GFP_KERNEL);
if (!imxdma)
return -ENOMEM;
INIT_LIST_HEAD(&imxdma->dma_device.channels);
dma_cap_set(DMA_SLAVE, imxdma->dma_device.cap_mask);
dma_cap_set(DMA_CYCLIC, imxdma->dma_device.cap_mask);
dma_cap_set(DMA_MEMCPY, imxdma->dma_device.cap_mask);
/* Initialize channel parameters */
for (i = 0; i < IMX_DMA_CHANNELS; i++) {
struct imxdma_channel *imxdmac = &imxdma->channel[i];
if (cpu_is_mx21() || cpu_is_mx27()) {
ret = request_irq(MX2x_INT_DMACH0 + i,
dma_irq_handler, 0, "DMA", imxdma);
if (ret) {
pr_crit("Can't register IRQ %d for DMA channel %d\n",
MX2x_INT_DMACH0 + i, i);
goto err_init;
}
init_timer(&imxdmac->watchdog);
imxdmac->watchdog.function = &imxdma_watchdog;
imxdmac->watchdog.data = (unsigned long)imxdmac;
}
imxdmac->imxdma = imxdma;
spin_lock_init(&imxdmac->lock);
INIT_LIST_HEAD(&imxdmac->ld_queue);
INIT_LIST_HEAD(&imxdmac->ld_free);
INIT_LIST_HEAD(&imxdmac->ld_active);
tasklet_init(&imxdmac->dma_tasklet, imxdma_tasklet,
(unsigned long)imxdmac);
imxdmac->chan.device = &imxdma->dma_device;
dma_cookie_init(&imxdmac->chan);
imxdmac->channel = i;
/* Add the channel to the DMAC list */
list_add_tail(&imxdmac->chan.device_node,
&imxdma->dma_device.channels);
}
imxdma->dev = &pdev->dev;
imxdma->dma_device.dev = &pdev->dev;
imxdma->dma_device.device_alloc_chan_resources = imxdma_alloc_chan_resources;
imxdma->dma_device.device_free_chan_resources = imxdma_free_chan_resources;
imxdma->dma_device.device_tx_status = imxdma_tx_status;
imxdma->dma_device.device_prep_slave_sg = imxdma_prep_slave_sg;
imxdma->dma_device.device_prep_dma_cyclic = imxdma_prep_dma_cyclic;
imxdma->dma_device.device_prep_dma_memcpy = imxdma_prep_dma_memcpy;
imxdma->dma_device.device_control = imxdma_control;
imxdma->dma_device.device_issue_pending = imxdma_issue_pending;
platform_set_drvdata(pdev, imxdma);
imxdma->dma_device.copy_align = 2; /* 2^2 = 4 bytes alignment */
imxdma->dma_device.dev->dma_parms = &imxdma->dma_parms;
dma_set_max_seg_size(imxdma->dma_device.dev, 0xffffff);
ret = dma_async_device_register(&imxdma->dma_device);
if (ret) {
dev_err(&pdev->dev, "unable to register\n");
goto err_init;
}
return 0;
err_init:
if (cpu_is_mx21() || cpu_is_mx27()) {
while (--i >= 0)
free_irq(MX2x_INT_DMACH0 + i, NULL);
} else if cpu_is_mx1() {
free_irq(MX1_DMA_INT, NULL);
free_irq(MX1_DMA_ERR, NULL);
}
kfree(imxdma);
return ret;
}
static int __exit imxdma_remove(struct platform_device *pdev)
{
struct imxdma_engine *imxdma = platform_get_drvdata(pdev);
int i;
dma_async_device_unregister(&imxdma->dma_device);
if (cpu_is_mx21() || cpu_is_mx27()) {
for (i = 0; i < IMX_DMA_CHANNELS; i++)
free_irq(MX2x_INT_DMACH0 + i, NULL);
} else if cpu_is_mx1() {
free_irq(MX1_DMA_INT, NULL);
free_irq(MX1_DMA_ERR, NULL);
}
kfree(imxdma);
return 0;
}
static struct platform_driver imxdma_driver = {
.driver = {
.name = "imx-dma",
},
.remove = __exit_p(imxdma_remove),
};
static int __init imxdma_module_init(void)
{
return platform_driver_probe(&imxdma_driver, imxdma_probe);
}
subsys_initcall(imxdma_module_init);
MODULE_AUTHOR("Sascha Hauer, Pengutronix <s.hauer@pengutronix.de>");
MODULE_DESCRIPTION("i.MX dma driver");
MODULE_LICENSE("GPL");