diff options
Diffstat (limited to 'drivers/dma/imx-sdma.c')
-rw-r--r-- | drivers/dma/imx-sdma.c | 68 |
1 files changed, 39 insertions, 29 deletions
diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c index fddccae..fb4f499 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) @@ -324,7 +325,7 @@ 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 +403,27 @@ 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 +435,17 @@ 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 +454,11 @@ 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; } @@ -535,13 +543,11 @@ 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); @@ -555,13 +561,15 @@ 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); } @@ -660,6 +668,7 @@ 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 +686,7 @@ 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 +705,9 @@ 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; } @@ -941,7 +949,7 @@ 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", @@ -1305,7 +1313,7 @@ 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; @@ -1376,6 +1384,8 @@ 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 |