From 7d2545599f5b09ccf6cdcab9ced58644a9cd038e Mon Sep 17 00:00:00 2001 From: Pramod Gurav Date: Fri, 17 Jun 2016 15:56:03 +0530 Subject: dmaengine: qcom-bam-dma: Add pm_runtime support Adds pm_runtime support for BAM DMA so that clock is enabled only when there is a transaction going on to help save power. Signed-off-by: Pramod Gurav Signed-off-by: Vinod Koul --- drivers/dma/qcom/bam_dma.c | 110 ++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 109 insertions(+), 1 deletion(-) (limited to 'drivers/dma/qcom') diff --git a/drivers/dma/qcom/bam_dma.c b/drivers/dma/qcom/bam_dma.c index 969b48176745..4754891742ad 100644 --- a/drivers/dma/qcom/bam_dma.c +++ b/drivers/dma/qcom/bam_dma.c @@ -48,6 +48,7 @@ #include #include #include +#include #include "../dmaengine.h" #include "../virt-dma.h" @@ -58,6 +59,8 @@ struct bam_desc_hw { __le16 flags; }; +#define BAM_DMA_AUTOSUSPEND_DELAY 100 + #define DESC_FLAG_INT BIT(15) #define DESC_FLAG_EOT BIT(14) #define DESC_FLAG_EOB BIT(13) @@ -527,12 +530,17 @@ static void bam_free_chan(struct dma_chan *chan) struct bam_device *bdev = bchan->bdev; u32 val; unsigned long flags; + int ret; + + ret = pm_runtime_get_sync(bdev->dev); + if (ret < 0) + return; vchan_free_chan_resources(to_virt_chan(chan)); if (bchan->curr_txd) { dev_err(bchan->bdev->dev, "Cannot free busy channel\n"); - return; + goto err; } spin_lock_irqsave(&bchan->vc.lock, flags); @@ -550,6 +558,10 @@ static void bam_free_chan(struct dma_chan *chan) /* disable irq */ writel_relaxed(0, bam_addr(bdev, bchan->id, BAM_P_IRQ_EN)); + +err: + pm_runtime_mark_last_busy(bdev->dev); + pm_runtime_put_autosuspend(bdev->dev); } /** @@ -696,11 +708,18 @@ static int bam_pause(struct dma_chan *chan) struct bam_chan *bchan = to_bam_chan(chan); struct bam_device *bdev = bchan->bdev; unsigned long flag; + int ret; + + ret = pm_runtime_get_sync(bdev->dev); + if (ret < 0) + return ret; spin_lock_irqsave(&bchan->vc.lock, flag); writel_relaxed(1, bam_addr(bdev, bchan->id, BAM_P_HALT)); bchan->paused = 1; spin_unlock_irqrestore(&bchan->vc.lock, flag); + pm_runtime_mark_last_busy(bdev->dev); + pm_runtime_put_autosuspend(bdev->dev); return 0; } @@ -715,11 +734,18 @@ static int bam_resume(struct dma_chan *chan) struct bam_chan *bchan = to_bam_chan(chan); struct bam_device *bdev = bchan->bdev; unsigned long flag; + int ret; + + ret = pm_runtime_get_sync(bdev->dev); + if (ret < 0) + return ret; spin_lock_irqsave(&bchan->vc.lock, flag); writel_relaxed(0, bam_addr(bdev, bchan->id, BAM_P_HALT)); bchan->paused = 0; spin_unlock_irqrestore(&bchan->vc.lock, flag); + pm_runtime_mark_last_busy(bdev->dev); + pm_runtime_put_autosuspend(bdev->dev); return 0; } @@ -795,6 +821,7 @@ static irqreturn_t bam_dma_irq(int irq, void *data) { struct bam_device *bdev = data; u32 clr_mask = 0, srcs = 0; + int ret; srcs |= process_channel_irqs(bdev); @@ -802,6 +829,10 @@ static irqreturn_t bam_dma_irq(int irq, void *data) if (srcs & P_IRQ) tasklet_schedule(&bdev->task); + ret = pm_runtime_get_sync(bdev->dev); + if (ret < 0) + return ret; + if (srcs & BAM_IRQ) { clr_mask = readl_relaxed(bam_addr(bdev, 0, BAM_IRQ_STTS)); @@ -814,6 +845,9 @@ static irqreturn_t bam_dma_irq(int irq, void *data) writel_relaxed(clr_mask, bam_addr(bdev, 0, BAM_IRQ_CLR)); } + pm_runtime_mark_last_busy(bdev->dev); + pm_runtime_put_autosuspend(bdev->dev); + return IRQ_HANDLED; } @@ -893,6 +927,7 @@ static void bam_start_dma(struct bam_chan *bchan) struct bam_desc_hw *desc; struct bam_desc_hw *fifo = PTR_ALIGN(bchan->fifo_virt, sizeof(struct bam_desc_hw)); + int ret; lockdep_assert_held(&bchan->vc.lock); @@ -904,6 +939,10 @@ static void bam_start_dma(struct bam_chan *bchan) async_desc = container_of(vd, struct bam_async_desc, vd); bchan->curr_txd = async_desc; + ret = pm_runtime_get_sync(bdev->dev); + if (ret < 0) + return; + /* on first use, initialize the channel hardware */ if (!bchan->initialized) bam_chan_init_hw(bchan, async_desc->dir); @@ -946,6 +985,9 @@ static void bam_start_dma(struct bam_chan *bchan) wmb(); writel_relaxed(bchan->tail * sizeof(struct bam_desc_hw), bam_addr(bdev, bchan->id, BAM_P_EVNT_REG)); + + pm_runtime_mark_last_busy(bdev->dev); + pm_runtime_put_autosuspend(bdev->dev); } /** @@ -970,6 +1012,7 @@ static void dma_tasklet(unsigned long data) bam_start_dma(bchan); spin_unlock_irqrestore(&bchan->vc.lock, flags); } + } /** @@ -1213,6 +1256,13 @@ static int bam_dma_probe(struct platform_device *pdev) if (ret) goto err_unregister_dma; + pm_runtime_irq_safe(&pdev->dev); + pm_runtime_set_autosuspend_delay(&pdev->dev, BAM_DMA_AUTOSUSPEND_DELAY); + pm_runtime_use_autosuspend(&pdev->dev); + pm_runtime_mark_last_busy(&pdev->dev); + pm_runtime_set_active(&pdev->dev); + pm_runtime_enable(&pdev->dev); + return 0; err_unregister_dma: @@ -1233,6 +1283,8 @@ static int bam_dma_remove(struct platform_device *pdev) struct bam_device *bdev = platform_get_drvdata(pdev); u32 i; + pm_runtime_force_suspend(&pdev->dev); + of_dma_controller_free(pdev->dev.of_node); dma_async_device_unregister(&bdev->common); @@ -1260,11 +1312,67 @@ static int bam_dma_remove(struct platform_device *pdev) return 0; } +static int bam_dma_runtime_suspend(struct device *dev) +{ + struct bam_device *bdev = dev_get_drvdata(dev); + + clk_disable(bdev->bamclk); + + return 0; +} + +static int bam_dma_runtime_resume(struct device *dev) +{ + struct bam_device *bdev = dev_get_drvdata(dev); + int ret; + + ret = clk_enable(bdev->bamclk); + if (ret < 0) { + dev_err(dev, "clk_enable failed: %d\n", ret); + return ret; + } + + return 0; +} +#ifdef CONFIG_PM_SLEEP +static int bam_dma_suspend(struct device *dev) +{ + struct bam_device *bdev = dev_get_drvdata(dev); + + pm_runtime_force_suspend(dev); + + clk_unprepare(bdev->bamclk); + + return 0; +} + +static int bam_dma_resume(struct device *dev) +{ + struct bam_device *bdev = dev_get_drvdata(dev); + int ret; + + ret = clk_prepare(bdev->bamclk); + if (ret) + return ret; + + pm_runtime_force_resume(dev); + + return 0; +} +#endif + +static const struct dev_pm_ops bam_dma_pm_ops = { + SET_LATE_SYSTEM_SLEEP_PM_OPS(bam_dma_suspend, bam_dma_resume) + SET_RUNTIME_PM_OPS(bam_dma_runtime_suspend, bam_dma_runtime_resume, + NULL) +}; + static struct platform_driver bam_dma_driver = { .probe = bam_dma_probe, .remove = bam_dma_remove, .driver = { .name = "bam-dma-engine", + .pm = &bam_dma_pm_ops, .of_match_table = bam_of_match, }, }; -- cgit v1.2.3 From 184f337e6d859c20e0d3c6954980cbb744e014fb Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Mon, 4 Jul 2016 15:14:08 +0200 Subject: dmaengine: qcom-bam-dma: add __maybe_unused annotations for PM The bam_dma driver gained runtime PM support, but that causes build warnings whenever CONFIG_PM is disabled: drivers/dma/qcom/bam_dma.c:1324:12: error: 'bam_dma_runtime_resume' defined but not used [-Werror=unused-function] static int bam_dma_runtime_resume(struct device *dev) ^~~~~~~~~~~~~~~~~~~~~~ drivers/dma/qcom/bam_dma.c:1315:12: error: 'bam_dma_runtime_suspend' defined but not used [-Werror=unused-function] static int bam_dma_runtime_suspend(struct device *dev) This removes the incomplete #ifdef guard and instead marks all four PM functions as __maybe_unused, which avoids this kind of warning. Signed-off-by: Arnd Bergmann Fixes: 7d2545599f5b ("dmaengine: qcom-bam-dma: Add pm_runtime support") Signed-off-by: Vinod Koul --- drivers/dma/qcom/bam_dma.c | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) (limited to 'drivers/dma/qcom') diff --git a/drivers/dma/qcom/bam_dma.c b/drivers/dma/qcom/bam_dma.c index 4754891742ad..03c4eb3fd314 100644 --- a/drivers/dma/qcom/bam_dma.c +++ b/drivers/dma/qcom/bam_dma.c @@ -1312,7 +1312,7 @@ static int bam_dma_remove(struct platform_device *pdev) return 0; } -static int bam_dma_runtime_suspend(struct device *dev) +static int __maybe_unused bam_dma_runtime_suspend(struct device *dev) { struct bam_device *bdev = dev_get_drvdata(dev); @@ -1321,7 +1321,7 @@ static int bam_dma_runtime_suspend(struct device *dev) return 0; } -static int bam_dma_runtime_resume(struct device *dev) +static int __maybe_unused bam_dma_runtime_resume(struct device *dev) { struct bam_device *bdev = dev_get_drvdata(dev); int ret; @@ -1334,8 +1334,8 @@ static int bam_dma_runtime_resume(struct device *dev) return 0; } -#ifdef CONFIG_PM_SLEEP -static int bam_dma_suspend(struct device *dev) + +static int __maybe_unused bam_dma_suspend(struct device *dev) { struct bam_device *bdev = dev_get_drvdata(dev); @@ -1346,7 +1346,7 @@ static int bam_dma_suspend(struct device *dev) return 0; } -static int bam_dma_resume(struct device *dev) +static int __maybe_unused bam_dma_resume(struct device *dev) { struct bam_device *bdev = dev_get_drvdata(dev); int ret; @@ -1359,7 +1359,6 @@ static int bam_dma_resume(struct device *dev) return 0; } -#endif static const struct dev_pm_ops bam_dma_pm_ops = { SET_LATE_SYSTEM_SLEEP_PM_OPS(bam_dma_suspend, bam_dma_resume) -- cgit v1.2.3