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authorLinus Torvalds <torvalds@linux-foundation.org>2012-05-25 09:31:59 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2012-05-25 09:31:59 -0700
commitd5adf235adc8d8d67c10afd43922c92753f6be3c (patch)
tree18c3cdcbc9a50a8cd00b03d83ec76bad7c7594f8 /drivers/dma/imx-sdma.c
parentd484864dd96e1830e7689510597707c1df8cd681 (diff)
parent1dd1ea8eb46a71201943148cc0ed3182cd04e288 (diff)
downloadlinux-d5adf235adc8d8d67c10afd43922c92753f6be3c.tar.bz2
Merge branch 'next' of git://git.infradead.org/users/vkoul/slave-dma
Pull slave-dmaengine updates from Vinod Koul: "Nothing exciting this time, odd fixes in a bunch of drivers" * 'next' of git://git.infradead.org/users/vkoul/slave-dma: dmaengine: at_hdmac: take maxburst from slave configuration dmaengine: at_hdmac: remove ATC_DEFAULT_CTRLA constant dmaengine: at_hdmac: remove some at_dma_slave comments dma: imx-sdma: make channel0 operations atomic dmaengine: Fixup dmaengine_prep_slave_single() to be actually useful dmaengine: Use dma_sg_len(sg) instead of sg->length dmaengine: Use sg_dma_address instead of sg_phys DMA: PL330: Remove duplicate header file inclusion dma: imx-sdma: keep the callbacks invoked in the tasklet dmaengine: dw_dma: add Device Tree probing capability dmaengine: dw_dmac: Add clk_{un}prepare() support dma/amba-pl08x: add support for the Nomadik variant dma/amba-pl08x: check for terminal count status only
Diffstat (limited to 'drivers/dma/imx-sdma.c')
-rw-r--r--drivers/dma/imx-sdma.c68
1 files changed, 39 insertions, 29 deletions
diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c
index d3e38e28bb6b..a472a29d8497 100644
--- a/drivers/dma/imx-sdma.c
+++ b/drivers/dma/imx-sdma.c
@@ -24,7 +24,7 @@
#include <linux/mm.h>
#include <linux/interrupt.h>
#include <linux/clk.h>
-#include <linux/wait.h>
+#include <linux/delay.h>
#include <linux/sched.h>
#include <linux/semaphore.h>
#include <linux/spinlock.h>
@@ -271,6 +271,7 @@ struct sdma_channel {
enum dma_status status;
unsigned int chn_count;
unsigned int chn_real_count;
+ struct tasklet_struct tasklet;
};
#define IMX_DMA_SG_LOOP BIT(0)
@@ -323,7 +324,7 @@ struct sdma_engine {
dma_addr_t context_phys;
struct dma_device dma_device;
struct clk *clk;
- struct mutex channel_0_lock;
+ spinlock_t channel_0_lock;
struct sdma_script_start_addrs *script_addrs;
};
@@ -401,19 +402,27 @@ static void sdma_enable_channel(struct sdma_engine *sdma, int channel)
}
/*
- * sdma_run_channel - run a channel and wait till it's done
+ * sdma_run_channel0 - run a channel and wait till it's done
*/
-static int sdma_run_channel(struct sdma_channel *sdmac)
+static int sdma_run_channel0(struct sdma_engine *sdma)
{
- struct sdma_engine *sdma = sdmac->sdma;
- int channel = sdmac->channel;
int ret;
+ unsigned long timeout = 500;
- init_completion(&sdmac->done);
+ sdma_enable_channel(sdma, 0);
- sdma_enable_channel(sdma, channel);
+ while (!(ret = readl_relaxed(sdma->regs + SDMA_H_INTR) & 1)) {
+ if (timeout-- <= 0)
+ break;
+ udelay(1);
+ }
- ret = wait_for_completion_timeout(&sdmac->done, HZ);
+ if (ret) {
+ /* Clear the interrupt status */
+ writel_relaxed(ret, sdma->regs + SDMA_H_INTR);
+ } else {
+ dev_err(sdma->dev, "Timeout waiting for CH0 ready\n");
+ }
return ret ? 0 : -ETIMEDOUT;
}
@@ -425,17 +434,17 @@ static int sdma_load_script(struct sdma_engine *sdma, void *buf, int size,
void *buf_virt;
dma_addr_t buf_phys;
int ret;
-
- mutex_lock(&sdma->channel_0_lock);
+ unsigned long flags;
buf_virt = dma_alloc_coherent(NULL,
size,
&buf_phys, GFP_KERNEL);
if (!buf_virt) {
- ret = -ENOMEM;
- goto err_out;
+ return -ENOMEM;
}
+ spin_lock_irqsave(&sdma->channel_0_lock, flags);
+
bd0->mode.command = C0_SETPM;
bd0->mode.status = BD_DONE | BD_INTR | BD_WRAP | BD_EXTD;
bd0->mode.count = size / 2;
@@ -444,12 +453,11 @@ static int sdma_load_script(struct sdma_engine *sdma, void *buf, int size,
memcpy(buf_virt, buf, size);
- ret = sdma_run_channel(&sdma->channel[0]);
+ ret = sdma_run_channel0(sdma);
- dma_free_coherent(NULL, size, buf_virt, buf_phys);
+ spin_unlock_irqrestore(&sdma->channel_0_lock, flags);
-err_out:
- mutex_unlock(&sdma->channel_0_lock);
+ dma_free_coherent(NULL, size, buf_virt, buf_phys);
return ret;
}
@@ -534,13 +542,11 @@ static void mxc_sdma_handle_channel_normal(struct sdma_channel *sdmac)
sdmac->desc.callback(sdmac->desc.callback_param);
}
-static void mxc_sdma_handle_channel(struct sdma_channel *sdmac)
+static void sdma_tasklet(unsigned long data)
{
- complete(&sdmac->done);
+ struct sdma_channel *sdmac = (struct sdma_channel *) data;
- /* not interested in channel 0 interrupts */
- if (sdmac->channel == 0)
- return;
+ complete(&sdmac->done);
if (sdmac->flags & IMX_DMA_SG_LOOP)
sdma_handle_channel_loop(sdmac);
@@ -554,13 +560,15 @@ static irqreturn_t sdma_int_handler(int irq, void *dev_id)
unsigned long stat;
stat = readl_relaxed(sdma->regs + SDMA_H_INTR);
+ /* not interested in channel 0 interrupts */
+ stat &= ~1;
writel_relaxed(stat, sdma->regs + SDMA_H_INTR);
while (stat) {
int channel = fls(stat) - 1;
struct sdma_channel *sdmac = &sdma->channel[channel];
- mxc_sdma_handle_channel(sdmac);
+ tasklet_schedule(&sdmac->tasklet);
__clear_bit(channel, &stat);
}
@@ -659,6 +667,7 @@ static int sdma_load_context(struct sdma_channel *sdmac)
struct sdma_context_data *context = sdma->context;
struct sdma_buffer_descriptor *bd0 = sdma->channel[0].bd;
int ret;
+ unsigned long flags;
if (sdmac->direction == DMA_DEV_TO_MEM) {
load_address = sdmac->pc_from_device;
@@ -676,7 +685,7 @@ static int sdma_load_context(struct sdma_channel *sdmac)
dev_dbg(sdma->dev, "event_mask0 = 0x%08x\n", (u32)sdmac->event_mask[0]);
dev_dbg(sdma->dev, "event_mask1 = 0x%08x\n", (u32)sdmac->event_mask[1]);
- mutex_lock(&sdma->channel_0_lock);
+ spin_lock_irqsave(&sdma->channel_0_lock, flags);
memset(context, 0, sizeof(*context));
context->channel_state.pc = load_address;
@@ -695,10 +704,9 @@ static int sdma_load_context(struct sdma_channel *sdmac)
bd0->mode.count = sizeof(*context) / 4;
bd0->buffer_addr = sdma->context_phys;
bd0->ext_buffer_addr = 2048 + (sizeof(*context) / 4) * channel;
+ ret = sdma_run_channel0(sdma);
- ret = sdma_run_channel(&sdma->channel[0]);
-
- mutex_unlock(&sdma->channel_0_lock);
+ spin_unlock_irqrestore(&sdma->channel_0_lock, flags);
return ret;
}
@@ -938,7 +946,7 @@ static struct dma_async_tx_descriptor *sdma_prep_slave_sg(
bd->buffer_addr = sg->dma_address;
- count = sg->length;
+ count = sg_dma_len(sg);
if (count > 0xffff) {
dev_err(sdma->dev, "SDMA channel %d: maximum bytes for sg entry exceeded: %d > %d\n",
@@ -1297,7 +1305,7 @@ static int __init sdma_probe(struct platform_device *pdev)
if (!sdma)
return -ENOMEM;
- mutex_init(&sdma->channel_0_lock);
+ spin_lock_init(&sdma->channel_0_lock);
sdma->dev = &pdev->dev;
@@ -1359,6 +1367,8 @@ static int __init sdma_probe(struct platform_device *pdev)
dma_cookie_init(&sdmac->chan);
sdmac->channel = i;
+ tasklet_init(&sdmac->tasklet, sdma_tasklet,
+ (unsigned long) sdmac);
/*
* Add the channel to the DMAC list. Do not add channel 0 though
* because we need it internally in the SDMA driver. This also means