Re: [PATCH 3/3] fpga: region: Adds runtime PM support

Moritz Fischer
2021-04-09T21:30:52Z

On Fri, Apr 02, 2021 at 02:50:49PM +0530, Nava kishore Manne wrote:
> Adds support to handle FPGA/PL power domain. With this patch,
> the PL power domain will be turned on before loading the bitstream
> and turned off while removing/unloading the bitstream using overlays.
> This can be achieved by adding the runtime PM support.
>
> Signed-off-by: Nava kishore Manne <nava.manne@xilinx.com>
> ---
> drivers/fpga/of-fpga-region.c | 18 +++++++++++++++++-
> 1 file changed, 17 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/fpga/of-fpga-region.c b/drivers/fpga/of-fpga-region.c
> index e405309baadc..35fc2f3d4bd8 100644
> --- a/drivers/fpga/of-fpga-region.c
> +++ b/drivers/fpga/of-fpga-region.c
> @@ -15,6 +15,7 @@
> #include <linux/of_platform.h>
> #include <linux/slab.h>
> #include <linux/spinlock.h>
> +#include <linux/pm_runtime.h>
>
> static const struct of_device_id fpga_region_of_match[] = {
> { .compatible = "fpga-region", },
> @@ -302,6 +303,7 @@ static int of_fpga_region_notify_pre_apply(struct fpga_region *region,
> }
>
> region->info = info;
> + pm_runtime_get_sync(dev->parent);
> ret = fpga_region_program_fpga(region);
> if (ret) {
> /* error; reject overlay */
> @@ -324,10 +326,13 @@ static int of_fpga_region_notify_pre_apply(struct fpga_region *region,
> static void of_fpga_region_notify_post_remove(struct fpga_region *region,
> struct of_overlay_notify_data *nd)
> {
> + struct device *dev = &region->dev;
> +
> fpga_bridges_disable(&region->bridge_list);
> fpga_bridges_put(&region->bridge_list);
> fpga_image_info_free(region->info);
> region->info = NULL;
> + pm_runtime_put(dev->parent);
> }
>
> /**
> @@ -411,9 +416,16 @@ static int of_fpga_region_probe(struct platform_device *pdev)
> goto eprobe_mgr_put;
> }
>
> + pm_runtime_enable(&pdev->dev);
> + ret = pm_runtime_get_sync(&pdev->dev);
> + if (ret < 0)
> + goto err_pm;
> +
> + pm_runtime_put(&pdev->dev);
> +
> ret = fpga_region_register(region);
> if (ret)
> - goto eprobe_mgr_put;
> + goto err_pm;
>
> of_platform_populate(np, fpga_region_of_match, NULL, &region->dev);
> platform_set_drvdata(pdev, region);
> @@ -422,6 +434,9 @@ static int of_fpga_region_probe(struct platform_device *pdev)
>
> return 0;
>
> +err_pm:
> + pm_runtime_put(&pdev->dev);
> + pm_runtime_disable(&pdev->dev);
> eprobe_mgr_put:
> fpga_mgr_put(mgr);
> return ret;
> @@ -434,6 +449,7 @@ static int of_fpga_region_remove(struct platform_device *pdev)
>
> fpga_region_unregister(region);
> fpga_mgr_put(mgr);
> + pm_runtime_disable(region->dev.parent);
>
> return 0;
> }
> --
> 2.18.0
>

Does this add a dependency on CONFIG_PM?

Thanks,
Moritz