Re: [PATCH v8 22/23] drm/mediatek: Power on devices in OVL adaptor when atomic enable

From: CK Hu (胡俊光)
Date: Tue Oct 17 2023 - 22:03:01 EST


Hi, Hsiao-chien:

On Mon, 2023-10-16 at 18:40 +0800, Hsiao Chien Sung wrote:
> Different from OVL, OVL adaptor is a pseudo device so we didn't
> define it in the device tree, consequently,
> pm_runtime_resume_and_get()
> called by .atomic_enable() powers on no device in OVL adaptor and
> leads to power outage in the corresponding IOMMU.
>
> To resolve the issue, we implement a function to power on the RDMAs
> in OVL adaptor, and the system will make sure the IOMMU is powered on
> as well because of the device link (iommus) in the RDMA nodes in DTS.
>
> Fixes: 5db12f5d843b ("media: drm/mediatek: Add pm runtime support for
> ovl and rdma")
>
> Signed-off-by: Hsiao Chien Sung <shawn.sung@xxxxxxxxxxxx>
> ---
> drivers/gpu/drm/mediatek/mtk_disp_drv.h | 4 ++
> .../gpu/drm/mediatek/mtk_disp_ovl_adaptor.c | 62
> +++++++++++++++++++
> drivers/gpu/drm/mediatek/mtk_drm_crtc.c | 28 +++------
> drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c | 2 +
> drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h | 20 ++++++
> drivers/gpu/drm/mediatek/mtk_mdp_rdma.c | 16 +++++
> 6 files changed, 111 insertions(+), 21 deletions(-)
>
> diff --git a/drivers/gpu/drm/mediatek/mtk_disp_drv.h
> b/drivers/gpu/drm/mediatek/mtk_disp_drv.h
> index e2b602037ac3..c44f5b31bab5 100644
> --- a/drivers/gpu/drm/mediatek/mtk_disp_drv.h
> +++ b/drivers/gpu/drm/mediatek/mtk_disp_drv.h
> @@ -109,6 +109,8 @@ void mtk_ovl_adaptor_connect(struct device *dev,
> struct device *mmsys_dev,
> unsigned int next);
> void mtk_ovl_adaptor_disconnect(struct device *dev, struct device
> *mmsys_dev,
> unsigned int next);
> +int mtk_ovl_adaptor_power_on(struct device *dev);
> +void mtk_ovl_adaptor_power_off(struct device *dev);
> int mtk_ovl_adaptor_clk_enable(struct device *dev);
> void mtk_ovl_adaptor_clk_disable(struct device *dev);
> void mtk_ovl_adaptor_config(struct device *dev, unsigned int w,
> @@ -150,6 +152,8 @@ void mtk_rdma_disable_vblank(struct device *dev);
> const u32 *mtk_rdma_get_formats(struct device *dev);
> size_t mtk_rdma_get_num_formats(struct device *dev);
>
> +int mtk_mdp_rdma_power_on(struct device *dev);
> +void mtk_mdp_rdma_power_off(struct device *dev);
> int mtk_mdp_rdma_clk_enable(struct device *dev);
> void mtk_mdp_rdma_clk_disable(struct device *dev);
> void mtk_mdp_rdma_start(struct device *dev, struct cmdq_pkt
> *cmdq_pkt);
> diff --git a/drivers/gpu/drm/mediatek/mtk_disp_ovl_adaptor.c
> b/drivers/gpu/drm/mediatek/mtk_disp_ovl_adaptor.c
> index b80425360e76..8de57a5f5518 100644
> --- a/drivers/gpu/drm/mediatek/mtk_disp_ovl_adaptor.c
> +++ b/drivers/gpu/drm/mediatek/mtk_disp_ovl_adaptor.c
> @@ -98,6 +98,8 @@ static const struct mtk_ddp_comp_funcs _padding = {
> };
>
> static const struct mtk_ddp_comp_funcs _rdma = {
> + .power_on = mtk_mdp_rdma_power_on,
> + .power_off = mtk_mdp_rdma_power_off,
> .clk_enable = mtk_mdp_rdma_clk_enable,
> .clk_disable = mtk_mdp_rdma_clk_disable,
> };
> @@ -241,6 +243,66 @@ void mtk_ovl_adaptor_stop(struct device *dev)
> }
> }
>
> +/**
> + * mtk_ovl_adaptor_power_on - Power on devices in OVL adaptor
> + * @dev: device to be powered on
> + *
> + * Different from OVL, OVL adaptor is a pseudo device so
> + * we didn't define it in the device tree,
> pm_runtime_resume_and_get()
> + * called by .atomic_enable() power on no device in OVL adaptor,
> + * we have to implement a function to do the job instead.
> + *
> + * returns:
> + * zero on success, errno on failures.
> + */
> +int mtk_ovl_adaptor_power_on(struct device *dev)
> +{
> + int i, ret;
> + struct mtk_disp_ovl_adaptor *ovl_adaptor =
> dev_get_drvdata(dev);
> +
> + for (i = 0; i < OVL_ADAPTOR_ID_MAX; i++) {
> + if (!ovl_adaptor->ovl_adaptor_comp[i] ||
> + !comp_matches[i].funcs->power_on)
> + continue;

To simplify the code, you could call mtk_ddp_comp_power_on() for all
sub device, and drop power_on()/power_off() of mdp_rdma.

Regards,
CK

> +
> + /*
> + * do not power on the devices that don't define
> + * .power_off() function
> + */
> + if (!comp_matches[i].funcs->power_off) {
> + dev_warn(dev, ".power_off() is undefined\n");
> + continue;
> + }
> +
> + ret = comp_matches[i].funcs->power_on(ovl_adaptor-
> >ovl_adaptor_comp[i]);
> + if (ret < 0) {
> + mtk_ovl_adaptor_power_off(dev);
> + return ret;
> + }
> + }
> + return 0;
> +}
> +
> +/**
> + * mtk_ovl_adaptor_power_off - Power off devices in OVL adaptor
> + * @dev: device to be powered off
> + *
> + * call .power_off() function if defined
> + */
> +void mtk_ovl_adaptor_power_off(struct device *dev)
> +{
> + int i;
> + struct mtk_disp_ovl_adaptor *ovl_adaptor =
> dev_get_drvdata(dev);
> +
> + for (i = 0; i < OVL_ADAPTOR_ID_MAX; i++) {
> + if (!ovl_adaptor->ovl_adaptor_comp[i] ||
> + !comp_matches[i].funcs->power_off)
> + continue;
> +
> + comp_matches[i].funcs->power_off(ovl_adaptor-
> >ovl_adaptor_comp[i]);
> + }
> +}
> +
> int mtk_ovl_adaptor_clk_enable(struct device *dev)
> {
> int i;
> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> index a0b2ba3cbcdb..c7edd80be428 100644
> --- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> +++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> @@ -6,7 +6,6 @@
> #include <linux/clk.h>
> #include <linux/dma-mapping.h>
> #include <linux/mailbox_controller.h>
> -#include <linux/pm_runtime.h>
> #include <linux/soc/mediatek/mtk-cmdq.h>
> #include <linux/soc/mediatek/mtk-mmsys.h>
> #include <linux/soc/mediatek/mtk-mutex.h>
> @@ -362,22 +361,16 @@ static int mtk_crtc_ddp_hw_init(struct
> mtk_drm_crtc *mtk_crtc, struct drm_atomic
> drm_connector_list_iter_end(&conn_iter);
> }
>
> - ret = pm_runtime_resume_and_get(crtc->dev->dev);
> - if (ret < 0) {
> - DRM_ERROR("Failed to enable power domain: %d\n", ret);
> - return ret;
> - }
> -
> ret = mtk_mutex_prepare(mtk_crtc->mutex);
> if (ret < 0) {
> DRM_ERROR("Failed to enable mutex clock: %d\n", ret);
> - goto err_pm_runtime_put;
> + goto error;
> }
>
> ret = mtk_crtc_ddp_clk_enable(mtk_crtc);
> if (ret < 0) {
> DRM_ERROR("Failed to enable component clocks: %d\n",
> ret);
> - goto err_mutex_unprepare;
> + goto error;
> }
>
> for (i = 0; i < mtk_crtc->ddp_comp_nr - 1; i++) {
> @@ -426,16 +419,13 @@ static int mtk_crtc_ddp_hw_init(struct
> mtk_drm_crtc *mtk_crtc, struct drm_atomic
>
> return 0;
>
> -err_mutex_unprepare:
> +error:
> mtk_mutex_unprepare(mtk_crtc->mutex);
> -err_pm_runtime_put:
> - pm_runtime_put(crtc->dev->dev);
> return ret;
> }
>
> static void mtk_crtc_ddp_hw_fini(struct mtk_drm_crtc *mtk_crtc)
> {
> - struct drm_device *drm = mtk_crtc->base.dev;
> struct drm_crtc *crtc = &mtk_crtc->base;
> int i;
>
> @@ -465,8 +455,6 @@ static void mtk_crtc_ddp_hw_fini(struct
> mtk_drm_crtc *mtk_crtc)
> mtk_crtc_ddp_clk_disable(mtk_crtc);
> mtk_mutex_unprepare(mtk_crtc->mutex);
>
> - pm_runtime_put(drm->dev);
> -
> if (crtc->state->event && !crtc->state->active) {
> spin_lock_irq(&crtc->dev->event_lock);
> drm_crtc_send_vblank_event(crtc, crtc->state->event);
> @@ -774,7 +762,7 @@ static void mtk_drm_crtc_atomic_enable(struct
> drm_crtc *crtc,
> return;
> }
>
> - ret = pm_runtime_resume_and_get(comp->dev);
> + ret = mtk_ddp_comp_power_on(comp);
> if (ret < 0) {
> DRM_DEV_ERROR(comp->dev, "Failed to enable power
> domain: %d\n", ret);
> return;
> @@ -782,7 +770,7 @@ static void mtk_drm_crtc_atomic_enable(struct
> drm_crtc *crtc,
>
> ret = mtk_crtc_ddp_hw_init(mtk_crtc, state);
> if (ret) {
> - pm_runtime_put(comp->dev);
> + mtk_ddp_comp_power_off(comp);
> return;
> }
>
> @@ -795,7 +783,7 @@ static void mtk_drm_crtc_atomic_disable(struct
> drm_crtc *crtc,
> {
> struct mtk_drm_crtc *mtk_crtc = to_mtk_crtc(crtc);
> struct mtk_ddp_comp *comp = mtk_crtc->ddp_comp[0];
> - int i, ret;
> + int i;
>
> DRM_DEBUG_DRIVER("%s %d\n", __func__, crtc->base.id);
> if (!mtk_crtc->enabled)
> @@ -825,9 +813,7 @@ static void mtk_drm_crtc_atomic_disable(struct
> drm_crtc *crtc,
>
> drm_crtc_vblank_off(crtc);
> mtk_crtc_ddp_hw_fini(mtk_crtc);
> - ret = pm_runtime_put(comp->dev);
> - if (ret < 0)
> - DRM_DEV_ERROR(comp->dev, "Failed to disable power
> domain: %d\n", ret);
> + mtk_ddp_comp_power_off(comp);
>
> mtk_crtc->enabled = false;
> }
> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
> b/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
> index 10402e07a4a7..9940909c7435 100644
> --- a/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
> +++ b/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.c
> @@ -396,6 +396,8 @@ static const struct mtk_ddp_comp_funcs ddp_ufoe =
> {
> };
>
> static const struct mtk_ddp_comp_funcs ddp_ovl_adaptor = {
> + .power_on = mtk_ovl_adaptor_power_on,
> + .power_off = mtk_ovl_adaptor_power_off,
> .clk_enable = mtk_ovl_adaptor_clk_enable,
> .clk_disable = mtk_ovl_adaptor_clk_disable,
> .config = mtk_ovl_adaptor_config,
> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h
> b/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h
> index 1c1d670cfe41..2597dd7ac0d2 100644
> --- a/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h
> +++ b/drivers/gpu/drm/mediatek/mtk_drm_ddp_comp.h
> @@ -7,6 +7,7 @@
> #define MTK_DRM_DDP_COMP_H
>
> #include <linux/io.h>
> +#include <linux/pm_runtime.h>
> #include <linux/soc/mediatek/mtk-cmdq.h>
> #include <linux/soc/mediatek/mtk-mmsys.h>
> #include <linux/soc/mediatek/mtk-mutex.h>
> @@ -46,6 +47,8 @@ enum mtk_ddp_comp_type {
> struct mtk_ddp_comp;
> struct cmdq_pkt;
> struct mtk_ddp_comp_funcs {
> + int (*power_on)(struct device *dev);
> + void (*power_off)(struct device *dev);
> int (*clk_enable)(struct device *dev);
> void (*clk_disable)(struct device *dev);
> void (*config)(struct device *dev, unsigned int w,
> @@ -91,6 +94,23 @@ struct mtk_ddp_comp {
> int encoder_index;
> };
>
> +static inline int mtk_ddp_comp_power_on(struct mtk_ddp_comp *comp)
> +{
> + if (comp->funcs && comp->funcs->power_on)
> + return comp->funcs->power_on(comp->dev);
> + else
> + return pm_runtime_resume_and_get(comp->dev);
> + return 0;
> +}
> +
> +static inline void mtk_ddp_comp_power_off(struct mtk_ddp_comp *comp)
> +{
> + if (comp->funcs && comp->funcs->power_off)
> + comp->funcs->power_off(comp->dev);
> + else
> + pm_runtime_put(comp->dev);
> +}
> +
> static inline int mtk_ddp_comp_clk_enable(struct mtk_ddp_comp *comp)
> {
> if (comp->funcs && comp->funcs->clk_enable)
> diff --git a/drivers/gpu/drm/mediatek/mtk_mdp_rdma.c
> b/drivers/gpu/drm/mediatek/mtk_mdp_rdma.c
> index cb36a961786f..8feeb6dce217 100644
> --- a/drivers/gpu/drm/mediatek/mtk_mdp_rdma.c
> +++ b/drivers/gpu/drm/mediatek/mtk_mdp_rdma.c
> @@ -243,6 +243,22 @@ size_t mtk_mdp_rdma_get_num_formats(struct
> device *dev)
> return ARRAY_SIZE(formats);
> }
>
> +int mtk_mdp_rdma_power_on(struct device *dev)
> +{
> + int ret = pm_runtime_resume_and_get(dev);
> +
> + if (ret < 0) {
> + dev_err(dev, "Failed to power on: %d\n", ret);
> + return ret;
> + }
> + return 0;
> +}
> +
> +void mtk_mdp_rdma_power_off(struct device *dev)
> +{
> + pm_runtime_put(dev);
> +}
> +
> int mtk_mdp_rdma_clk_enable(struct device *dev)
> {
> struct mtk_mdp_rdma *rdma = dev_get_drvdata(dev);