On Wed, 21 Dec 2022 at 18:14, Akhil P Oommen <quic_akhilpo@xxxxxxxxxxx> wrote:
>
> As per the recommended recovery sequence of adreno gpu, cx gdsc should
> collapse at hardware before it is turned back ON. This helps to clear
> out the stale states in hardware before it is reinitialized. Use the
> genpd notifier along with the newly introduced
> dev_pm_genpd_synced_poweroff() api to ensure that cx gdsc has collapsed
> before we turn it back ON.
>
> Signed-off-by: Akhil P Oommen <quic_akhilpo@xxxxxxxxxxx>
Reviewed-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
Kind regards
Uffe
> ---
>
> (no changes since v2)
>
> Changes in v2:
> - Select PM_GENERIC_DOMAINS from Kconfig
>
> drivers/gpu/drm/msm/Kconfig | 1 +
> drivers/gpu/drm/msm/adreno/a6xx_gmu.c | 15 +++++++++++++++
> drivers/gpu/drm/msm/adreno/a6xx_gmu.h | 6 ++++++
> drivers/gpu/drm/msm/adreno/a6xx_gpu.c | 11 +++++++++++
> 4 files changed, 33 insertions(+)
>
> diff --git a/drivers/gpu/drm/msm/Kconfig b/drivers/gpu/drm/msm/Kconfig
> index 3c9dfdb0b328..74f5916f5ca5 100644
> --- a/drivers/gpu/drm/msm/Kconfig
> +++ b/drivers/gpu/drm/msm/Kconfig
> @@ -28,6 +28,7 @@ config DRM_MSM
> select SYNC_FILE
> select PM_OPP
> select NVMEM
> + select PM_GENERIC_DOMAINS
> help
> DRM/KMS driver for MSM/snapdragon.
>
> diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gmu.c b/drivers/gpu/drm/msm/adreno/a6xx_gmu.c
> index 1580d0090f35..c03830957c26 100644
> --- a/drivers/gpu/drm/msm/adreno/a6xx_gmu.c
> +++ b/drivers/gpu/drm/msm/adreno/a6xx_gmu.c
> @@ -1507,6 +1507,17 @@ void a6xx_gmu_remove(struct a6xx_gpu *a6xx_gpu)
> gmu->initialized = false;
> }
>
> +static int cxpd_notifier_cb(struct notifier_block *nb,
> + unsigned long action, void *data)
> +{
> + struct a6xx_gmu *gmu = container_of(nb, struct a6xx_gmu, pd_nb);
> +
> + if (action == GENPD_NOTIFY_OFF)
> + complete_all(&gmu->pd_gate);
> +
> + return 0;
> +}
> +
> int a6xx_gmu_init(struct a6xx_gpu *a6xx_gpu, struct device_node *node)
> {
> struct adreno_gpu *adreno_gpu = &a6xx_gpu->base;
> @@ -1640,6 +1651,10 @@ int a6xx_gmu_init(struct a6xx_gpu *a6xx_gpu, struct device_node *node)
> goto detach_cxpd;
> }
>
> + init_completion(&gmu->pd_gate);
> + complete_all(&gmu->pd_gate);
> + gmu->pd_nb.notifier_call = cxpd_notifier_cb;
> +
> /*
> * Get a link to the GX power domain to reset the GPU in case of GMU
> * crash
> diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gmu.h b/drivers/gpu/drm/msm/adreno/a6xx_gmu.h
> index 5a42dd4dd31f..0bc3eb443fec 100644
> --- a/drivers/gpu/drm/msm/adreno/a6xx_gmu.h
> +++ b/drivers/gpu/drm/msm/adreno/a6xx_gmu.h
> @@ -4,8 +4,10 @@
> #ifndef _A6XX_GMU_H_
> #define _A6XX_GMU_H_
>
> +#include <linux/completion.h>
> #include <linux/iopoll.h>
> #include <linux/interrupt.h>
> +#include <linux/notifier.h>
> #include "msm_drv.h"
> #include "a6xx_hfi.h"
>
> @@ -90,6 +92,10 @@ struct a6xx_gmu {
> bool initialized;
> bool hung;
> bool legacy; /* a618 or a630 */
> +
> + /* For power domain callback */
> + struct notifier_block pd_nb;
> + struct completion pd_gate;
> };
>
> static inline u32 gmu_read(struct a6xx_gmu *gmu, u32 offset)
> diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
> index 4b16e75dfa50..dd618b099110 100644
> --- a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
> +++ b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
> @@ -10,6 +10,7 @@
>
> #include <linux/bitfield.h>
> #include <linux/devfreq.h>
> +#include <linux/pm_domain.h>
> #include <linux/soc/qcom/llcc-qcom.h>
>
> #define GPU_PAS_ID 13
> @@ -1258,6 +1259,7 @@ static void a6xx_recover(struct msm_gpu *gpu)
> {
> struct adreno_gpu *adreno_gpu = to_adreno_gpu(gpu);
> struct a6xx_gpu *a6xx_gpu = to_a6xx_gpu(adreno_gpu);
> + struct a6xx_gmu *gmu = &a6xx_gpu->gmu;
> int i, active_submits;
>
> adreno_dump_info(gpu);
> @@ -1290,6 +1292,10 @@ static void a6xx_recover(struct msm_gpu *gpu)
> */
> gpu->active_submits = 0;
>
> + reinit_completion(&gmu->pd_gate);
> + dev_pm_genpd_add_notifier(gmu->cxpd, &gmu->pd_nb);
> + dev_pm_genpd_synced_poweroff(gmu->cxpd);
> +
> /* Drop the rpm refcount from active submits */
> if (active_submits)
> pm_runtime_put(&gpu->pdev->dev);
> @@ -1297,6 +1303,11 @@ static void a6xx_recover(struct msm_gpu *gpu)
> /* And the final one from recover worker */
> pm_runtime_put_sync(&gpu->pdev->dev);
>
> + if (!wait_for_completion_timeout(&gmu->pd_gate, msecs_to_jiffies(1000)))
> + DRM_DEV_ERROR(&gpu->pdev->dev, "cx gdsc didn't collapse\n");
> +
> + dev_pm_genpd_remove_notifier(gmu->cxpd);
> +
> pm_runtime_use_autosuspend(&gpu->pdev->dev);
>
> if (active_submits)
> --
> 2.7.4
>
