On Wed, 2012-05-09 at 19:33 +0800, Richard Zhao wrote:
device_prep_dma_cyclic may be call in audio trigger function which is atomic context, so we make it atomic too.
- change channel0 lock to spinlock.
- Use polling to wait for channel0 finish running.
Signed-off-by: Richard Zhao richard.zhao@freescale.com
Can you pls rebase this against the slave-dma next and resend. It fails to apply for me.
drivers/dma/imx-sdma.c | 57 ++++++++++++++++++++++++++--------------------- 1 files changed, 31 insertions(+), 26 deletions(-)
diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c index fddccae..4fd48eb 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> @@ -324,7 +324,7 @@ struct sdma_engine { struct dma_device dma_device; struct clk *clk_ipg; struct clk *clk_ahb;
- struct mutex channel_0_lock;
- spinlock_t channel_0_lock; struct sdma_script_start_addrs *script_addrs;
};
@@ -402,19 +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;
} @@ -426,17 +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;
@@ -445,12 +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;
} @@ -539,10 +546,6 @@ static void mxc_sdma_handle_channel(struct sdma_channel *sdmac) { complete(&sdmac->done);
- /* not interested in channel 0 interrupts */
- if (sdmac->channel == 0)
return;- if (sdmac->flags & IMX_DMA_SG_LOOP) sdma_handle_channel_loop(sdmac); else
@@ -555,6 +558,8 @@ 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) {
@@ -660,6 +665,7 @@ 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;
@@ -677,7 +683,7 @@ 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;
@@ -696,10 +702,9 @@ 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;
} @@ -1305,7 +1310,7 @@ 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;