Convert gm12u320 to direct primary plane, CRTC and encoder setup.
Keep shadow-plane helper state, framebuffer access helpers and
no-scaling plane-state check from simple-KMS path.
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Tested-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Ze Huang <ze.huang@oss.qualcomm.com>
---
drivers/gpu/drm/tiny/gm12u320.c | 132 ++++++++++++++++++++++++++++++++--------
1 file changed, 107 insertions(+), 25 deletions(-)
diff --git a/drivers/gpu/drm/tiny/gm12u320.c b/drivers/gpu/drm/tiny/gm12u320.c
index d73dfebb4353..df60968856e5 100644
--- a/drivers/gpu/drm/tiny/gm12u320.c
+++ b/drivers/gpu/drm/tiny/gm12u320.c
@@ -8,6 +8,7 @@
#include <linux/usb.h>
#include <drm/clients/drm_client_setup.h>
+#include <drm/drm_atomic.h>
#include <drm/drm_atomic_helper.h>
#include <drm/drm_atomic_state_helper.h>
#include <drm/drm_connector.h>
@@ -27,7 +28,6 @@
#include <drm/drm_modeset_helper_vtables.h>
#include <drm/drm_print.h>
#include <drm/drm_probe_helper.h>
-#include <drm/drm_simple_kms_helper.h>
static bool eco_mode;
module_param(eco_mode, bool, 0644);
@@ -87,7 +87,9 @@ MODULE_PARM_DESC(eco_mode, "Turn on Eco mode (less bright, more silent)");
struct gm12u320_device {
struct drm_device dev;
- struct drm_simple_display_pipe pipe;
+ struct drm_plane plane;
+ struct drm_crtc crtc;
+ struct drm_encoder encoder;
struct drm_connector conn;
unsigned char *cmd_buf;
unsigned char *data_buf[GM12U320_BLOCK_COUNT];
@@ -102,7 +104,10 @@ struct gm12u320_device {
} fb_update;
};
-#define to_gm12u320(__dev) container_of(__dev, struct gm12u320_device, dev)
+static struct gm12u320_device *to_gm12u320(struct drm_device *__dev)
+{
+ return container_of(__dev, struct gm12u320_device, dev);
+}
static const char cmd_data[CMD_SIZE] = {
0x55, 0x53, 0x42, 0x43, 0x00, 0x00, 0x00, 0x00,
@@ -554,43 +559,104 @@ static int gm12u320_conn_init(struct gm12u320_device *gm12u320)
}
/* ------------------------------------------------------------------ */
-/* gm12u320 (simple) display pipe */
+/* gm12u320 display pipe */
-static void gm12u320_pipe_enable(struct drm_simple_display_pipe *pipe,
- struct drm_crtc_state *crtc_state,
- struct drm_plane_state *plane_state)
+static void gm12u320_crtc_helper_atomic_enable(struct drm_crtc *crtc,
+ struct drm_atomic_commit *commit)
{
struct drm_rect rect = { 0, 0, GM12U320_USER_WIDTH, GM12U320_HEIGHT };
- struct gm12u320_device *gm12u320 = to_gm12u320(pipe->crtc.dev);
+ struct gm12u320_device *gm12u320 = to_gm12u320(crtc->dev);
+ struct drm_plane_state *plane_state = gm12u320->plane.state;
struct drm_shadow_plane_state *shadow_plane_state = to_drm_shadow_plane_state(plane_state);
gm12u320->fb_update.draw_status_timeout = FIRST_FRAME_TIMEOUT;
gm12u320_fb_mark_dirty(plane_state->fb, &shadow_plane_state->data[0], &rect);
}
-static void gm12u320_pipe_disable(struct drm_simple_display_pipe *pipe)
+static void gm12u320_crtc_helper_atomic_disable(struct drm_crtc *crtc,
+ struct drm_atomic_commit *commit)
{
- struct gm12u320_device *gm12u320 = to_gm12u320(pipe->crtc.dev);
+ struct gm12u320_device *gm12u320 = to_gm12u320(crtc->dev);
gm12u320_stop_fb_update(gm12u320);
}
-static void gm12u320_pipe_update(struct drm_simple_display_pipe *pipe,
- struct drm_plane_state *old_state)
+static void gm12u320_plane_helper_atomic_update(struct drm_plane *plane,
+ struct drm_atomic_commit *commit)
{
- struct drm_plane_state *state = pipe->plane.state;
+ struct drm_plane_state *old_state = drm_atomic_get_old_plane_state(commit, plane);
+ struct drm_plane_state *state = drm_atomic_get_new_plane_state(commit, plane);
struct drm_shadow_plane_state *shadow_plane_state = to_drm_shadow_plane_state(state);
struct drm_rect rect;
+ if (!state->fb)
+ return;
+
if (drm_atomic_helper_damage_merged(old_state, state, &rect))
gm12u320_fb_mark_dirty(state->fb, &shadow_plane_state->data[0], &rect);
}
-static const struct drm_simple_display_pipe_funcs gm12u320_pipe_funcs = {
- .enable = gm12u320_pipe_enable,
- .disable = gm12u320_pipe_disable,
- .update = gm12u320_pipe_update,
- DRM_GEM_SIMPLE_DISPLAY_PIPE_SHADOW_PLANE_FUNCS,
+static const struct drm_plane_funcs gm12u320_plane_funcs = {
+ .update_plane = drm_atomic_helper_update_plane,
+ .disable_plane = drm_atomic_helper_disable_plane,
+ .destroy = drm_plane_cleanup,
+ DRM_GEM_SHADOW_PLANE_FUNCS,
+};
+
+static int gm12u320_plane_helper_atomic_check(struct drm_plane *plane,
+ struct drm_atomic_commit *commit)
+{
+ struct drm_plane_state *plane_state = drm_atomic_get_new_plane_state(commit, plane);
+ struct drm_crtc *crtc = plane_state->crtc;
+ struct drm_crtc_state *crtc_state = NULL;
+
+ if (crtc)
+ crtc_state = drm_atomic_get_new_crtc_state(commit, crtc);
+
+ return drm_atomic_helper_check_plane_state(plane_state, crtc_state,
+ DRM_PLANE_NO_SCALING,
+ DRM_PLANE_NO_SCALING,
+ false, false);
+}
+
+static const struct drm_plane_helper_funcs gm12u320_plane_helper_funcs = {
+ DRM_GEM_SHADOW_PLANE_HELPER_FUNCS,
+ .atomic_check = gm12u320_plane_helper_atomic_check,
+ .atomic_update = gm12u320_plane_helper_atomic_update,
+};
+
+static int gm12u320_crtc_helper_atomic_check(struct drm_crtc *crtc,
+ struct drm_atomic_commit *commit)
+{
+ struct drm_crtc_state *crtc_state = drm_atomic_get_new_crtc_state(commit, crtc);
+ int ret;
+
+ if (crtc_state->enable) {
+ ret = drm_atomic_helper_check_crtc_primary_plane(crtc_state);
+ if (ret)
+ return ret;
+ }
+
+ return drm_atomic_add_affected_planes(commit, crtc);
+}
+
+static const struct drm_crtc_helper_funcs gm12u320_crtc_helper_funcs = {
+ .atomic_check = gm12u320_crtc_helper_atomic_check,
+ .atomic_enable = gm12u320_crtc_helper_atomic_enable,
+ .atomic_disable = gm12u320_crtc_helper_atomic_disable,
+};
+
+static const struct drm_crtc_funcs gm12u320_crtc_funcs = {
+ .set_config = drm_atomic_helper_set_config,
+ .page_flip = drm_atomic_helper_page_flip,
+ .reset = drm_atomic_helper_crtc_reset,
+ .destroy = drm_crtc_cleanup,
+ .atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
+ .atomic_destroy_state = drm_atomic_helper_crtc_destroy_state,
+};
+
+static const struct drm_encoder_funcs gm12u320_encoder_funcs = {
+ .destroy = drm_encoder_cleanup,
};
static const uint32_t gm12u320_pipe_formats[] = {
@@ -677,13 +743,29 @@ static int gm12u320_usb_probe(struct usb_interface *interface,
if (ret)
return ret;
- ret = drm_simple_display_pipe_init(&gm12u320->dev,
- &gm12u320->pipe,
- &gm12u320_pipe_funcs,
- gm12u320_pipe_formats,
- ARRAY_SIZE(gm12u320_pipe_formats),
- gm12u320_pipe_modifiers,
- &gm12u320->conn);
+ ret = drm_universal_plane_init(dev, &gm12u320->plane, 0,
+ &gm12u320_plane_funcs,
+ gm12u320_pipe_formats,
+ ARRAY_SIZE(gm12u320_pipe_formats),
+ gm12u320_pipe_modifiers,
+ DRM_PLANE_TYPE_PRIMARY, NULL);
+ if (ret)
+ return ret;
+ drm_plane_helper_add(&gm12u320->plane, &gm12u320_plane_helper_funcs);
+
+ ret = drm_crtc_init_with_planes(dev, &gm12u320->crtc, &gm12u320->plane, NULL,
+ &gm12u320_crtc_funcs, NULL);
+ if (ret)
+ return ret;
+ drm_crtc_helper_add(&gm12u320->crtc, &gm12u320_crtc_helper_funcs);
+
+ ret = drm_encoder_init(dev, &gm12u320->encoder, &gm12u320_encoder_funcs,
+ DRM_MODE_ENCODER_NONE, NULL);
+ if (ret)
+ return ret;
+ gm12u320->encoder.possible_crtcs = drm_crtc_mask(&gm12u320->crtc);
+
+ ret = drm_connector_attach_encoder(&gm12u320->conn, &gm12u320->encoder);
if (ret)
return ret;
--
2.43.0Hi
Am 16.07.26 um 11:01 schrieb Ze Huang:
> Convert gm12u320 to direct primary plane, CRTC and encoder setup.
>
> Keep shadow-plane helper state, framebuffer access helpers and
> no-scaling plane-state check from simple-KMS path.
>
> Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
> Tested-by: Thomas Zimmermann <tzimmermann@suse.de>
> Signed-off-by: Ze Huang <ze.huang@oss.qualcomm.com>
> ---
> drivers/gpu/drm/tiny/gm12u320.c | 132 ++++++++++++++++++++++++++++++++--------
> 1 file changed, 107 insertions(+), 25 deletions(-)
>
[...]
>
> -static void gm12u320_pipe_enable(struct drm_simple_display_pipe *pipe,
> - struct drm_crtc_state *crtc_state,
> - struct drm_plane_state *plane_state)
> +static void gm12u320_crtc_helper_atomic_enable(struct drm_crtc *crtc,
> + struct drm_atomic_commit *commit)
> {
> struct drm_rect rect = { 0, 0, GM12U320_USER_WIDTH, GM12U320_HEIGHT };
> - struct gm12u320_device *gm12u320 = to_gm12u320(pipe->crtc.dev);
> + struct gm12u320_device *gm12u320 = to_gm12u320(crtc->dev);
> + struct drm_plane_state *plane_state = gm12u320->plane.state;
Did you see the reply from the Sashiko bot?
What happens is that user space can apply multiple atomic commits in a
row, but they are applied to hardware asynchronously. So if you take the
plane state here directly from the plane, it could have been replaced by
a later atomic commit already. Rather get the correct plane state with
the helper drm_atomic_get_new_plane_state(). I did not look at all of
the series' patches for this problem, but the rule applies to all of the
mode-setting code. Best regards Thomas
> struct drm_shadow_plane_state *shadow_plane_state = to_drm_shadow_plane_state(plane_state);
>
> gm12u320->fb_update.draw_status_timeout = FIRST_FRAME_TIMEOUT;
> gm12u320_fb_mark_dirty(plane_state->fb, &shadow_plane_state->data[0], &rect);
> }
>
> -static void gm12u320_pipe_disable(struct drm_simple_display_pipe *pipe)
> +static void gm12u320_crtc_helper_atomic_disable(struct drm_crtc *crtc,
> + struct drm_atomic_commit *commit)
> {
> - struct gm12u320_device *gm12u320 = to_gm12u320(pipe->crtc.dev);
> + struct gm12u320_device *gm12u320 = to_gm12u320(crtc->dev);
>
> gm12u320_stop_fb_update(gm12u320);
> }
>
> -static void gm12u320_pipe_update(struct drm_simple_display_pipe *pipe,
> - struct drm_plane_state *old_state)
> +static void gm12u320_plane_helper_atomic_update(struct drm_plane *plane,
> + struct drm_atomic_commit *commit)
> {
> - struct drm_plane_state *state = pipe->plane.state;
> + struct drm_plane_state *old_state = drm_atomic_get_old_plane_state(commit, plane);
> + struct drm_plane_state *state = drm_atomic_get_new_plane_state(commit, plane);
> struct drm_shadow_plane_state *shadow_plane_state = to_drm_shadow_plane_state(state);
> struct drm_rect rect;
>
> + if (!state->fb)
> + return;
> +
> if (drm_atomic_helper_damage_merged(old_state, state, &rect))
> gm12u320_fb_mark_dirty(state->fb, &shadow_plane_state->data[0], &rect);
> }
>
> -static const struct drm_simple_display_pipe_funcs gm12u320_pipe_funcs = {
> - .enable = gm12u320_pipe_enable,
> - .disable = gm12u320_pipe_disable,
> - .update = gm12u320_pipe_update,
> - DRM_GEM_SIMPLE_DISPLAY_PIPE_SHADOW_PLANE_FUNCS,
> +static const struct drm_plane_funcs gm12u320_plane_funcs = {
> + .update_plane = drm_atomic_helper_update_plane,
> + .disable_plane = drm_atomic_helper_disable_plane,
> + .destroy = drm_plane_cleanup,
> + DRM_GEM_SHADOW_PLANE_FUNCS,
> +};
> +
> +static int gm12u320_plane_helper_atomic_check(struct drm_plane *plane,
> + struct drm_atomic_commit *commit)
> +{
> + struct drm_plane_state *plane_state = drm_atomic_get_new_plane_state(commit, plane);
> + struct drm_crtc *crtc = plane_state->crtc;
> + struct drm_crtc_state *crtc_state = NULL;
> +
> + if (crtc)
> + crtc_state = drm_atomic_get_new_crtc_state(commit, crtc);
> +
> + return drm_atomic_helper_check_plane_state(plane_state, crtc_state,
> + DRM_PLANE_NO_SCALING,
> + DRM_PLANE_NO_SCALING,
> + false, false);
> +}
> +
> +static const struct drm_plane_helper_funcs gm12u320_plane_helper_funcs = {
> + DRM_GEM_SHADOW_PLANE_HELPER_FUNCS,
> + .atomic_check = gm12u320_plane_helper_atomic_check,
> + .atomic_update = gm12u320_plane_helper_atomic_update,
> +};
> +
> +static int gm12u320_crtc_helper_atomic_check(struct drm_crtc *crtc,
> + struct drm_atomic_commit *commit)
> +{
> + struct drm_crtc_state *crtc_state = drm_atomic_get_new_crtc_state(commit, crtc);
> + int ret;
> +
> + if (crtc_state->enable) {
> + ret = drm_atomic_helper_check_crtc_primary_plane(crtc_state);
> + if (ret)
> + return ret;
> + }
> +
> + return drm_atomic_add_affected_planes(commit, crtc);
> +}
> +
> +static const struct drm_crtc_helper_funcs gm12u320_crtc_helper_funcs = {
> + .atomic_check = gm12u320_crtc_helper_atomic_check,
> + .atomic_enable = gm12u320_crtc_helper_atomic_enable,
> + .atomic_disable = gm12u320_crtc_helper_atomic_disable,
> +};
> +
> +static const struct drm_crtc_funcs gm12u320_crtc_funcs = {
> + .set_config = drm_atomic_helper_set_config,
> + .page_flip = drm_atomic_helper_page_flip,
> + .reset = drm_atomic_helper_crtc_reset,
> + .destroy = drm_crtc_cleanup,
> + .atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
> + .atomic_destroy_state = drm_atomic_helper_crtc_destroy_state,
> +};
> +
> +static const struct drm_encoder_funcs gm12u320_encoder_funcs = {
> + .destroy = drm_encoder_cleanup,
> };
>
> static const uint32_t gm12u320_pipe_formats[] = {
> @@ -677,13 +743,29 @@ static int gm12u320_usb_probe(struct usb_interface *interface,
> if (ret)
> return ret;
>
> - ret = drm_simple_display_pipe_init(&gm12u320->dev,
> - &gm12u320->pipe,
> - &gm12u320_pipe_funcs,
> - gm12u320_pipe_formats,
> - ARRAY_SIZE(gm12u320_pipe_formats),
> - gm12u320_pipe_modifiers,
> - &gm12u320->conn);
> + ret = drm_universal_plane_init(dev, &gm12u320->plane, 0,
> + &gm12u320_plane_funcs,
> + gm12u320_pipe_formats,
> + ARRAY_SIZE(gm12u320_pipe_formats),
> + gm12u320_pipe_modifiers,
> + DRM_PLANE_TYPE_PRIMARY, NULL);
> + if (ret)
> + return ret;
> + drm_plane_helper_add(&gm12u320->plane, &gm12u320_plane_helper_funcs);
> +
> + ret = drm_crtc_init_with_planes(dev, &gm12u320->crtc, &gm12u320->plane, NULL,
> + &gm12u320_crtc_funcs, NULL);
> + if (ret)
> + return ret;
> + drm_crtc_helper_add(&gm12u320->crtc, &gm12u320_crtc_helper_funcs);
> +
> + ret = drm_encoder_init(dev, &gm12u320->encoder, &gm12u320_encoder_funcs,
> + DRM_MODE_ENCODER_NONE, NULL);
> + if (ret)
> + return ret;
> + gm12u320->encoder.possible_crtcs = drm_crtc_mask(&gm12u320->crtc);
> +
> + ret = drm_connector_attach_encoder(&gm12u320->conn, &gm12u320->encoder);
> if (ret)
> return ret;
>
>
--
--
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Frankenstr. 146, 90461 Nürnberg, Germany, www.suse.com
GF: Jochen Jaser, Andrew McDonald, (HRB 36809, AG Nürnberg)
On Fri Jul 17, 2026 at 3:18 PM CST, Thomas Zimmermann wrote:
> Hi
>
> Am 16.07.26 um 11:01 schrieb Ze Huang:
>> Convert gm12u320 to direct primary plane, CRTC and encoder setup.
>>
>> Keep shadow-plane helper state, framebuffer access helpers and
>> no-scaling plane-state check from simple-KMS path.
>>
>> Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
>> Tested-by: Thomas Zimmermann <tzimmermann@suse.de>
>> Signed-off-by: Ze Huang <ze.huang@oss.qualcomm.com>
>> ---
>> drivers/gpu/drm/tiny/gm12u320.c | 132 ++++++++++++++++++++++++++++++++--------
>> 1 file changed, 107 insertions(+), 25 deletions(-)
>>
> [...]
>>
>> -static void gm12u320_pipe_enable(struct drm_simple_display_pipe *pipe,
>> - struct drm_crtc_state *crtc_state,
>> - struct drm_plane_state *plane_state)
>> +static void gm12u320_crtc_helper_atomic_enable(struct drm_crtc *crtc,
>> + struct drm_atomic_commit *commit)
>> {
>> struct drm_rect rect = { 0, 0, GM12U320_USER_WIDTH, GM12U320_HEIGHT };
>> - struct gm12u320_device *gm12u320 = to_gm12u320(pipe->crtc.dev);
>> + struct gm12u320_device *gm12u320 = to_gm12u320(crtc->dev);
>> + struct drm_plane_state *plane_state = gm12u320->plane.state;
>
> Did you see the reply from the Sashiko bot?
>
> What happens is that user space can apply multiple atomic commits in a
> row, but they are applied to hardware asynchronously. So if you take the
> plane state here directly from the plane, it could have been replaced by
> a later atomic commit already. Rather get the correct plane state with
> the helper drm_atomic_get_new_plane_state().
>
I think I misunderstood this point. I had assumed that
drm_atomic_get_*_state() was only needed for the state object directly
matching the helper callback, for example crtc_state in
*_crtc_helper_atomic_enable() and plane_state in
*_plane_helper_atomic_update(), while other state could be accessed via
the device-private structure.
From your explanation, I see that this is wrong. In the atomic commit
path, any state associated with the current commit should be obtained
through drm_atomic_get_*_state(), because the object’s ->state may
already refer to a later commit.
> I did not look at all of the series' patches for this problem, but the rule
> applies to all of the mode-setting code.
>
> Best regards
> Thomas
This affects other patches in the series as well, and some drivers may
need additional fixes in internal helpers too, e.g. arc_pgu_set_pxl_fmt()
in arcpgu.c [1].
I will audit the full series and fix such cases in the next version.
Best regards
Ze
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