[PATCH] dmaengine: zynqmp_dma: Add runtime pm support
Michal Simek
michal.simek at xilinx.com
Thu Oct 19 23:31:38 PDT 2017
On 18.10.2017 09:02, Kedareswara rao Appana wrote:
> This patch adds runtime pm support in the driver.
>
> Signed-off-by: Kedareswara rao Appana <appanad at xilinx.com>
> ---
> drivers/dma/xilinx/zynqmp_dma.c | 167 ++++++++++++++++++++++++++++++++--------
> 1 file changed, 135 insertions(+), 32 deletions(-)
>
> diff --git a/drivers/dma/xilinx/zynqmp_dma.c b/drivers/dma/xilinx/zynqmp_dma.c
> index 1ee1241..dd73831 100644
> --- a/drivers/dma/xilinx/zynqmp_dma.c
> +++ b/drivers/dma/xilinx/zynqmp_dma.c
> @@ -23,6 +23,7 @@
> #include <linux/slab.h>
> #include <linux/clk.h>
> #include <linux/io-64-nonatomic-lo-hi.h>
> +#include <linux/pm_runtime.h>
>
> #include "../dmaengine.h"
>
> @@ -138,6 +139,8 @@
> #define ZYNQMP_DMA_BUS_WIDTH_64 64
> #define ZYNQMP_DMA_BUS_WIDTH_128 128
>
> +#define ZDMA_PM_TIMEOUT 100
> +
> #define ZYNQMP_DMA_DESC_SIZE(chan) (chan->desc_size)
>
> #define to_chan(chan) container_of(chan, struct zynqmp_dma_chan, \
> @@ -211,8 +214,6 @@ struct zynqmp_dma_desc_sw {
> * @bus_width: Bus width
> * @src_burst_len: Source burst length
> * @dst_burst_len: Dest burst length
> - * @clk_main: Pointer to main clock
> - * @clk_apb: Pointer to apb clock
> */
> struct zynqmp_dma_chan {
> struct zynqmp_dma_device *zdev;
> @@ -237,8 +238,6 @@ struct zynqmp_dma_chan {
> u32 bus_width;
> u32 src_burst_len;
> u32 dst_burst_len;
> - struct clk *clk_main;
> - struct clk *clk_apb;
> };
>
> /**
> @@ -246,11 +245,15 @@ struct zynqmp_dma_chan {
> * @dev: Device Structure
> * @common: DMA device structure
> * @chan: Driver specific DMA channel
> + * @clk_main: Pointer to main clock
> + * @clk_apb: Pointer to apb clock
> */
> struct zynqmp_dma_device {
> struct device *dev;
> struct dma_device common;
> struct zynqmp_dma_chan *chan;
> + struct clk *clk_main;
> + struct clk *clk_apb;
> };
>
> static inline void zynqmp_dma_writeq(struct zynqmp_dma_chan *chan, u32 reg,
> @@ -461,7 +464,11 @@ static int zynqmp_dma_alloc_chan_resources(struct dma_chan *dchan)
> {
> struct zynqmp_dma_chan *chan = to_chan(dchan);
> struct zynqmp_dma_desc_sw *desc;
> - int i;
> + int i, ret;
> +
> + ret = pm_runtime_get_sync(chan->dev);
> + if (ret < 0)
> + return ret;
>
> chan->sw_desc_pool = kzalloc(sizeof(*desc) * ZYNQMP_DMA_NUM_DESCS,
> GFP_KERNEL);
> @@ -664,6 +671,8 @@ static void zynqmp_dma_free_chan_resources(struct dma_chan *dchan)
> (2 * ZYNQMP_DMA_DESC_SIZE(chan) * ZYNQMP_DMA_NUM_DESCS),
> chan->desc_pool_v, chan->desc_pool_p);
> kfree(chan->sw_desc_pool);
> + pm_runtime_mark_last_busy(chan->dev);
> + pm_runtime_put_autosuspend(chan->dev);
> }
>
> /**
> @@ -841,8 +850,6 @@ static void zynqmp_dma_chan_remove(struct zynqmp_dma_chan *chan)
> devm_free_irq(chan->zdev->dev, chan->irq, chan);
> tasklet_kill(&chan->tasklet);
> list_del(&chan->common.device_node);
> - clk_disable_unprepare(chan->clk_apb);
> - clk_disable_unprepare(chan->clk_main);
> }
>
> /**
> @@ -907,30 +914,6 @@ static int zynqmp_dma_chan_probe(struct zynqmp_dma_device *zdev,
> "zynqmp-dma", chan);
> if (err)
> return err;
> - chan->clk_main = devm_clk_get(&pdev->dev, "clk_main");
> - if (IS_ERR(chan->clk_main)) {
> - dev_err(&pdev->dev, "main clock not found.\n");
> - return PTR_ERR(chan->clk_main);
> - }
> -
> - chan->clk_apb = devm_clk_get(&pdev->dev, "clk_apb");
> - if (IS_ERR(chan->clk_apb)) {
> - dev_err(&pdev->dev, "apb clock not found.\n");
> - return PTR_ERR(chan->clk_apb);
> - }
> -
> - err = clk_prepare_enable(chan->clk_main);
> - if (err) {
> - dev_err(&pdev->dev, "Unable to enable main clock.\n");
> - return err;
> - }
> -
> - err = clk_prepare_enable(chan->clk_apb);
> - if (err) {
> - clk_disable_unprepare(chan->clk_main);
> - dev_err(&pdev->dev, "Unable to enable apb clock.\n");
> - return err;
> - }
>
> chan->desc_size = sizeof(struct zynqmp_dma_desc_ll);
> chan->idle = true;
> @@ -953,6 +936,87 @@ static struct dma_chan *of_zynqmp_dma_xlate(struct of_phandle_args *dma_spec,
> }
>
> /**
> + * zynqmp_dma_suspend - Suspend method for the driver
> + * @dev: Address of the device structure
> + *
> + * Put the driver into low power mode.
> + * Return: 0 on success and failure value on error
> + */
> +static int __maybe_unused zynqmp_dma_suspend(struct device *dev)
> +{
> + if (!device_may_wakeup(dev))
> + return pm_runtime_force_suspend(dev);
> +
> + return 0;
> +}
> +
> +/**
> + * zynqmp_dma_resume - Resume from suspend
> + * @dev: Address of the device structure
> + *
> + * Resume operation after suspend.
> + * Return: 0 on success and failure value on error
> + */
> +static int __maybe_unused zynqmp_dma_resume(struct device *dev)
> +{
> + if (!device_may_wakeup(dev))
> + return pm_runtime_force_resume(dev);
> +
> + return 0;
> +}
> +
> +/**
> + * zynqmp_dma_runtime_suspend - Runtime suspend method for the driver
> + * @dev: Address of the device structure
> + *
> + * Put the driver into low power mode.
> + * Return: 0 always
> + */
> +static int __maybe_unused zynqmp_dma_runtime_suspend(struct device *dev)
> +{
> + struct zynqmp_dma_device *zdev = dev_get_drvdata(dev);
> +
> + clk_disable_unprepare(zdev->clk_main);
> + clk_disable_unprepare(zdev->clk_apb);
> +
> + return 0;
> +}
> +
> +/**
> + * zynqmp_dma_runtime_resume - Runtime suspend method for the driver
> + * @dev: Address of the device structure
> + *
> + * Put the driver into low power mode.
> + * Return: 0 always
> + */
> +static int __maybe_unused zynqmp_dma_runtime_resume(struct device *dev)
> +{
> + struct zynqmp_dma_device *zdev = dev_get_drvdata(dev);
> + int err;
> +
> + err = clk_prepare_enable(zdev->clk_main);
> + if (err) {
> + dev_err(dev, "Unable to enable main clock.\n");
> + return err;
> + }
> +
> + err = clk_prepare_enable(zdev->clk_apb);
> + if (err) {
> + dev_err(dev, "Unable to enable apb clock.\n");
> + clk_disable_unprepare(zdev->clk_main);
> + return err;
> + }
> +
> + return 0;
> +}
> +
> +static const struct dev_pm_ops zynqmp_dma_dev_pm_ops = {
> + SET_SYSTEM_SLEEP_PM_OPS(zynqmp_dma_suspend, zynqmp_dma_resume)
> + SET_RUNTIME_PM_OPS(zynqmp_dma_runtime_suspend,
> + zynqmp_dma_runtime_resume, NULL)
> +};
> +
> +/**
> * zynqmp_dma_probe - Driver probe function
> * @pdev: Pointer to the platform_device structure
> *
> @@ -984,12 +1048,39 @@ static int zynqmp_dma_probe(struct platform_device *pdev)
> p->device_config = zynqmp_dma_device_config;
> p->dev = &pdev->dev;
>
> + zdev->clk_main = devm_clk_get(&pdev->dev, "clk_main");
> + if (IS_ERR(zdev->clk_main)) {
> + dev_err(&pdev->dev, "main clock not found.\n");
> + return PTR_ERR(zdev->clk_main);
> + }
> +
> + zdev->clk_apb = devm_clk_get(&pdev->dev, "clk_apb");
> + if (IS_ERR(zdev->clk_apb)) {
> + dev_err(&pdev->dev, "apb clock not found.\n");
> + return PTR_ERR(zdev->clk_apb);
> + }
> +
> + ret = clk_prepare_enable(zdev->clk_main);
> + if (ret) {
> + dev_err(&pdev->dev, "Unable to enable main clock.\n");
> + return ret;
> + }
> +
> + ret = clk_prepare_enable(zdev->clk_apb);
> + if (ret) {
> + dev_err(&pdev->dev, "Unable to enable apb clock.\n");
> + goto err_disable_clk;
> + }
> +
> platform_set_drvdata(pdev, zdev);
> + pm_runtime_set_autosuspend_delay(zdev->dev, ZDMA_PM_TIMEOUT);
> + pm_runtime_use_autosuspend(zdev->dev);
> + pm_runtime_enable(zdev->dev);
>
> ret = zynqmp_dma_chan_probe(zdev, pdev);
> if (ret) {
> dev_err(&pdev->dev, "Probing channel failed\n");
> - goto free_chan_resources;
> + goto err_disable_pm;
> }
>
> p->dst_addr_widths = BIT(zdev->chan->bus_width / 8);
> @@ -1005,10 +1096,18 @@ static int zynqmp_dma_probe(struct platform_device *pdev)
> goto free_chan_resources;
> }
>
> + pm_runtime_mark_last_busy(zdev->dev);
> + pm_runtime_put_sync_autosuspend(zdev->dev);
> +
> dev_info(&pdev->dev, "ZynqMP DMA driver Probe success\n");
>
> return 0;
>
> +err_disable_clk:
> + clk_disable_unprepare(zdev->clk_main);
> +err_disable_pm:
> + clk_disable_unprepare(zdev->clk_apb);
> + pm_runtime_disable(zdev->dev);
> free_chan_resources:
> zynqmp_dma_chan_remove(zdev->chan);
> return ret;
> @@ -1028,6 +1127,9 @@ static int zynqmp_dma_remove(struct platform_device *pdev)
> dma_async_device_unregister(&zdev->common);
>
> zynqmp_dma_chan_remove(zdev->chan);
> + pm_runtime_disable(zdev->dev);
> + clk_disable_unprepare(zdev->clk_apb);
> + clk_disable_unprepare(zdev->clk_main);
>
> return 0;
> }
> @@ -1042,6 +1144,7 @@ static struct platform_driver zynqmp_dma_driver = {
> .driver = {
> .name = "xilinx-zynqmp-dma",
> .of_match_table = zynqmp_dma_of_match,
> + .pm = &zynqmp_dma_dev_pm_ops,
> },
> .probe = zynqmp_dma_probe,
> .remove = zynqmp_dma_remove,
>
CR number?
M
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