2023-02-21 08:12:42

by Yongqiang Niu

[permalink] [raw]
Subject: [PATCH v2] drm/mediatek: add dma buffer control for drm plane disable

dma buffer release before overlay disable, that will cause
m4u translation fault warning.

add dma buffer control flow in mediatek driver:
get dma buffer when drm plane disable
put dma buffer when overlay really disable

Signed-off-by: Yongqiang Niu <[email protected]>
---
drivers/gpu/drm/mediatek/mtk_drm_crtc.c | 19 +++++++++++++++++--
drivers/gpu/drm/mediatek/mtk_drm_plane.c | 12 ++++++++++++
drivers/gpu/drm/mediatek/mtk_drm_plane.h | 1 +
3 files changed, 30 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
index 5071f1263216..ff7924d8a167 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
+++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
@@ -4,6 +4,7 @@
*/

#include <linux/clk.h>
+#include <linux/dma-buf.h>
#include <linux/dma-mapping.h>
#include <linux/mailbox_controller.h>
#include <linux/pm_runtime.h>
@@ -282,6 +283,14 @@ struct mtk_ddp_comp *mtk_drm_ddp_comp_for_plane(struct drm_crtc *crtc,
return NULL;
}

+static void mtk_drm_dma_buf_put(struct mtk_plane_state *plane_state)
+{
+ if (plane_state && plane_state->pending.dma_buf) {
+ dma_buf_put(plane_state->pending.dma_buf);
+ plane_state->pending.dma_buf = NULL;
+ }
+}
+
#if IS_REACHABLE(CONFIG_MTK_CMDQ)
static void ddp_cmdq_cb(struct mbox_client *cl, void *mssg)
{
@@ -306,6 +315,7 @@ static void ddp_cmdq_cb(struct mbox_client *cl, void *mssg)
plane_state = to_mtk_plane_state(plane->state);

plane_state->pending.config = false;
+ mtk_drm_dma_buf_put(plane_state);
}
mtk_crtc->pending_planes = false;
}
@@ -318,6 +328,7 @@ static void ddp_cmdq_cb(struct mbox_client *cl, void *mssg)
plane_state = to_mtk_plane_state(plane->state);

plane_state->pending.async_config = false;
+ mtk_drm_dma_buf_put(plane_state);
}
mtk_crtc->pending_async_planes = false;
}
@@ -498,8 +509,10 @@ static void mtk_crtc_ddp_config(struct drm_crtc *crtc,
mtk_ddp_comp_layer_config(comp, local_layer,
plane_state,
cmdq_handle);
- if (!cmdq_handle)
+ if (!cmdq_handle) {
plane_state->pending.config = false;
+ mtk_drm_dma_buf_put(plane_state);
+ }
}

if (!cmdq_handle)
@@ -523,8 +536,10 @@ static void mtk_crtc_ddp_config(struct drm_crtc *crtc,
mtk_ddp_comp_layer_config(comp, local_layer,
plane_state,
cmdq_handle);
- if (!cmdq_handle)
+ if (!cmdq_handle) {
plane_state->pending.async_config = false;
+ mtk_drm_dma_buf_put(plane_state);
+ }
}

if (!cmdq_handle)
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_plane.c b/drivers/gpu/drm/mediatek/mtk_drm_plane.c
index d54fbf34b000..16495a057c42 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_plane.c
+++ b/drivers/gpu/drm/mediatek/mtk_drm_plane.c
@@ -12,6 +12,7 @@
#include <drm/drm_framebuffer.h>
#include <drm/drm_gem_atomic_helper.h>
#include <linux/align.h>
+#include <linux/dma-buf.h>

#include "mtk_drm_crtc.h"
#include "mtk_drm_ddp_comp.h"
@@ -280,6 +281,17 @@ static void mtk_plane_atomic_disable(struct drm_plane *plane,
struct drm_plane_state *new_state = drm_atomic_get_new_plane_state(state,
plane);
struct mtk_plane_state *mtk_plane_state = to_mtk_plane_state(new_state);
+ struct drm_plane_state *old_state = drm_atomic_get_old_plane_state(state,
+ plane);
+
+ if (old_state && old_state->fb) {
+ struct drm_gem_object *gem = old_state->fb->obj[0];
+
+ if (gem && gem->dma_buf) {
+ get_dma_buf(gem->dma_buf);
+ mtk_plane_state->pending.dma_buf = gem->dma_buf;
+ }
+ }
mtk_plane_state->pending.enable = false;
wmb(); /* Make sure the above parameter is set before update */
mtk_plane_state->pending.dirty = true;
diff --git a/drivers/gpu/drm/mediatek/mtk_drm_plane.h b/drivers/gpu/drm/mediatek/mtk_drm_plane.h
index 8f39011cdbfc..b724e56b7283 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_plane.h
+++ b/drivers/gpu/drm/mediatek/mtk_drm_plane.h
@@ -33,6 +33,7 @@ struct mtk_plane_pending_state {
bool async_dirty;
bool async_config;
enum drm_color_encoding color_encoding;
+ struct dma_buf *dma_buf;
};

struct mtk_plane_state {
--
2.25.1



2023-02-27 02:25:52

by Chun-Kuang Hu

[permalink] [raw]
Subject: Re: [PATCH v2] drm/mediatek: add dma buffer control for drm plane disable

Hi, Yongqiang:

Yongqiang Niu <[email protected]> 於 2023年2月21日 週二 下午4:12寫道:
>
> dma buffer release before overlay disable, that will cause
> m4u translation fault warning.
>
> add dma buffer control flow in mediatek driver:
> get dma buffer when drm plane disable
> put dma buffer when overlay really disable

Add Fixes tag.

>
> Signed-off-by: Yongqiang Niu <[email protected]>
> ---
> drivers/gpu/drm/mediatek/mtk_drm_crtc.c | 19 +++++++++++++++++--
> drivers/gpu/drm/mediatek/mtk_drm_plane.c | 12 ++++++++++++
> drivers/gpu/drm/mediatek/mtk_drm_plane.h | 1 +
> 3 files changed, 30 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> index 5071f1263216..ff7924d8a167 100644
> --- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> +++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
> @@ -4,6 +4,7 @@
> */
>
> #include <linux/clk.h>
> +#include <linux/dma-buf.h>
> #include <linux/dma-mapping.h>
> #include <linux/mailbox_controller.h>
> #include <linux/pm_runtime.h>
> @@ -282,6 +283,14 @@ struct mtk_ddp_comp *mtk_drm_ddp_comp_for_plane(struct drm_crtc *crtc,
> return NULL;
> }
>
> +static void mtk_drm_dma_buf_put(struct mtk_plane_state *plane_state)
> +{
> + if (plane_state && plane_state->pending.dma_buf) {
> + dma_buf_put(plane_state->pending.dma_buf);
> + plane_state->pending.dma_buf = NULL;
> + }
> +}
> +
> #if IS_REACHABLE(CONFIG_MTK_CMDQ)
> static void ddp_cmdq_cb(struct mbox_client *cl, void *mssg)
> {
> @@ -306,6 +315,7 @@ static void ddp_cmdq_cb(struct mbox_client *cl, void *mssg)
> plane_state = to_mtk_plane_state(plane->state);
>
> plane_state->pending.config = false;
> + mtk_drm_dma_buf_put(plane_state);
> }
> mtk_crtc->pending_planes = false;
> }
> @@ -318,6 +328,7 @@ static void ddp_cmdq_cb(struct mbox_client *cl, void *mssg)
> plane_state = to_mtk_plane_state(plane->state);
>
> plane_state->pending.async_config = false;
> + mtk_drm_dma_buf_put(plane_state);
> }
> mtk_crtc->pending_async_planes = false;
> }
> @@ -498,8 +509,10 @@ static void mtk_crtc_ddp_config(struct drm_crtc *crtc,
> mtk_ddp_comp_layer_config(comp, local_layer,
> plane_state,
> cmdq_handle);
> - if (!cmdq_handle)
> + if (!cmdq_handle) {
> plane_state->pending.config = false;
> + mtk_drm_dma_buf_put(plane_state);

In shadow register case, it would also call into here, but it should
put dma buf in irq handler.

> + }
> }
>
> if (!cmdq_handle)
> @@ -523,8 +536,10 @@ static void mtk_crtc_ddp_config(struct drm_crtc *crtc,
> mtk_ddp_comp_layer_config(comp, local_layer,
> plane_state,
> cmdq_handle);
> - if (!cmdq_handle)
> + if (!cmdq_handle) {
> plane_state->pending.async_config = false;
> + mtk_drm_dma_buf_put(plane_state);
> + }
> }
>
> if (!cmdq_handle)
> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_plane.c b/drivers/gpu/drm/mediatek/mtk_drm_plane.c
> index d54fbf34b000..16495a057c42 100644
> --- a/drivers/gpu/drm/mediatek/mtk_drm_plane.c
> +++ b/drivers/gpu/drm/mediatek/mtk_drm_plane.c
> @@ -12,6 +12,7 @@
> #include <drm/drm_framebuffer.h>
> #include <drm/drm_gem_atomic_helper.h>
> #include <linux/align.h>
> +#include <linux/dma-buf.h>
>
> #include "mtk_drm_crtc.h"
> #include "mtk_drm_ddp_comp.h"
> @@ -280,6 +281,17 @@ static void mtk_plane_atomic_disable(struct drm_plane *plane,
> struct drm_plane_state *new_state = drm_atomic_get_new_plane_state(state,
> plane);
> struct mtk_plane_state *mtk_plane_state = to_mtk_plane_state(new_state);
> + struct drm_plane_state *old_state = drm_atomic_get_old_plane_state(state,
> + plane);
> +
> + if (old_state && old_state->fb) {
> + struct drm_gem_object *gem = old_state->fb->obj[0];
> +
> + if (gem && gem->dma_buf) {
> + get_dma_buf(gem->dma_buf);
> + mtk_plane_state->pending.dma_buf = gem->dma_buf;

Should we check old pending.dma_buf is null here or somewhere else?
I would like to make sure that old dma buf is put before new dma buf
need to be put.

Regards,
Chun-Kuang.

> + }
> + }
> mtk_plane_state->pending.enable = false;
> wmb(); /* Make sure the above parameter is set before update */
> mtk_plane_state->pending.dirty = true;
> diff --git a/drivers/gpu/drm/mediatek/mtk_drm_plane.h b/drivers/gpu/drm/mediatek/mtk_drm_plane.h
> index 8f39011cdbfc..b724e56b7283 100644
> --- a/drivers/gpu/drm/mediatek/mtk_drm_plane.h
> +++ b/drivers/gpu/drm/mediatek/mtk_drm_plane.h
> @@ -33,6 +33,7 @@ struct mtk_plane_pending_state {
> bool async_dirty;
> bool async_config;
> enum drm_color_encoding color_encoding;
> + struct dma_buf *dma_buf;
> };
>
> struct mtk_plane_state {
> --
> 2.25.1
>