Re: [PATCH 2/9] drm/aspeed: replace struct drm_simple_display_pipe with regular atomic helpers

["Ze Huang" <ze.huang@xxxxxxxxxxxxxxxx>]

On Mon Jul 6, 2026 at 4:31 PM CST, Thomas Zimmermann wrote:
> Hi,
>
> common points from my arcgpu review applied here as well. See below for 
> a new other things.
>
> Am 04.07.26 um 20:31 schrieb Ze Huang:
>> Replace simple display pipe with explicit plane, CRTC and encoder
>> objects. Move callbacks to plane and CRTC helpers, with vblank handling
>> through drm_crtc_funcs.
>>
>> This removes intermediate simple-pipe layer and uses standard atomic
>> helper wiring.
>>
>> Signed-off-by: Ze Huang <ze.huang@xxxxxxxxxxxxxxxx>
>> ---
>>   drivers/gpu/drm/aspeed/aspeed_gfx.h      |   5 +-
>>   drivers/gpu/drm/aspeed/aspeed_gfx_crtc.c | 156 
>> +++++++++++++++++++++++--------
>>   drivers/gpu/drm/aspeed/aspeed_gfx_drv.c  |   3 +-
>>   3 files changed, 123 insertions(+), 41 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/aspeed/aspeed_gfx.h 
>> b/drivers/gpu/drm/aspeed/aspeed_gfx.h
>> index 4e6a442c3886..a34811564c0d 100644
>> --- a/drivers/gpu/drm/aspeed/aspeed_gfx.h
>> +++ b/drivers/gpu/drm/aspeed/aspeed_gfx.h
>> @@ -2,7 +2,6 @@
>>   /* Copyright 2018 IBM Corporation */
>>   
>>   #include <drm/drm_device.h>
>> -#include <drm/drm_simple_kms_helper.h>
>>   
>>   struct aspeed_gfx {
>>      struct drm_device               drm;
>> @@ -17,7 +16,9 @@ struct aspeed_gfx {
>>      u32                             throd_val;
>>      u32                             scan_line_max;
>>   
>> -    struct drm_simple_display_pipe  pipe;
>> +    struct drm_plane                plane;
>> +    struct drm_crtc                 crtc;
>> +    struct drm_encoder              encoder;
>>      struct drm_connector            connector;
>>   };
>>   #define to_aspeed_gfx(x) container_of(x, struct aspeed_gfx, drm)
>> diff --git a/drivers/gpu/drm/aspeed/aspeed_gfx_crtc.c 
>> b/drivers/gpu/drm/aspeed/aspeed_gfx_crtc.c
>> index 7877a57b8e26..3294795c31c4 100644
>> --- a/drivers/gpu/drm/aspeed/aspeed_gfx_crtc.c
>> +++ b/drivers/gpu/drm/aspeed/aspeed_gfx_crtc.c
>> @@ -5,6 +5,8 @@
>>   #include <linux/reset.h>
>>   #include <linux/regmap.h>
>>   
>> +#include <drm/drm_atomic.h>
>> +#include <drm/drm_atomic_helper.h>
>>   #include <drm/drm_device.h>
>>   #include <drm/drm_fb_dma_helper.h>
>>   #include <drm/drm_fourcc.h>
>> @@ -12,20 +14,13 @@
>>   #include <drm/drm_gem_atomic_helper.h>
>>   #include <drm/drm_gem_dma_helper.h>
>>   #include <drm/drm_panel.h>
>> -#include <drm/drm_simple_kms_helper.h>
>>   #include <drm/drm_vblank.h>
>>   
>>   #include "aspeed_gfx.h"
>>   
>> -static struct aspeed_gfx *
>> -drm_pipe_to_aspeed_gfx(struct drm_simple_display_pipe *pipe)
>> -{
>> -    return container_of(pipe, struct aspeed_gfx, pipe);
>> -}
>> -
>
> Please create a new helper
>
>    struct drm_aspeed_gfx *to_aspeed_gfx(drm_device *drm)
>
> that does the upcast.
>

Will do

>>   static int aspeed_gfx_set_pixel_fmt(struct aspeed_gfx *priv, u32 *bpp)
>>   {
>> -    struct drm_crtc *crtc = &priv->pipe.crtc;
>> +    struct drm_crtc *crtc = &priv->crtc;
>>      struct drm_device *drm = crtc->dev;
>>      const u32 format = crtc->primary->state->fb->format->format;
>>      u32 ctrl1;
>> @@ -79,7 +74,7 @@ static void aspeed_gfx_disable_controller(struct 
>> aspeed_gfx *priv)
>>   
>>   static void aspeed_gfx_crtc_mode_set_nofb(struct aspeed_gfx *priv)
>>   {
>> -    struct drm_display_mode *m = &priv->pipe.crtc.state->adjusted_mode;
>> +    struct drm_display_mode *m = &priv->crtc.state->adjusted_mode;
>>      u32 ctrl1, d_offset, t_count, bpp;
>>      int err;
>>   
>> @@ -139,33 +134,31 @@ static void aspeed_gfx_crtc_mode_set_nofb(struct 
>> aspeed_gfx *priv)
>>      writel(priv->throd_val, priv->base + CRT_THROD);
>>   }
>>   
>> -static void aspeed_gfx_pipe_enable(struct drm_simple_display_pipe *pipe,
>> -                          struct drm_crtc_state *crtc_state,
>> -                          struct drm_plane_state *plane_state)
>> +static void aspeed_gfx_crtc_helper_atomic_enable(struct drm_crtc *crtc,
>> +                                             struct drm_atomic_commit 
>> *state)
>
> Please see my comment on arcgpu for the new naming of 'state'.
>

OK

>>   {
>> -    struct aspeed_gfx *priv = drm_pipe_to_aspeed_gfx(pipe);
>> -    struct drm_crtc *crtc = &pipe->crtc;
>> +    struct aspeed_gfx *priv = container_of(crtc, struct aspeed_gfx, crtc);
>
> Please use  your helper  to_aspeed_gfx(crtc->dev)  to do the upcast.  
> Here any in other places.
>

OK

>>   
>>      aspeed_gfx_crtc_mode_set_nofb(priv);
>>      aspeed_gfx_enable_controller(priv);
>>      drm_crtc_vblank_on(crtc);
>>   }
>>   
>> -static void aspeed_gfx_pipe_disable(struct drm_simple_display_pipe *pipe)
>> +static void aspeed_gfx_crtc_helper_atomic_disable(struct drm_crtc *crtc,
>> +                                              struct drm_atomic_commit 
>> *state)
>>   {
>> -    struct aspeed_gfx *priv = drm_pipe_to_aspeed_gfx(pipe);
>> -    struct drm_crtc *crtc = &pipe->crtc;
>> +    struct aspeed_gfx *priv = container_of(crtc, struct aspeed_gfx, crtc);
>
> Another upcast issue
>

Acknowledged

>>   
>>      drm_crtc_vblank_off(crtc);
>>      aspeed_gfx_disable_controller(priv);
>>   }
>>   
>> -static void aspeed_gfx_pipe_update(struct drm_simple_display_pipe *pipe,
>> -                               struct drm_plane_state *plane_state)
>> +static void aspeed_gfx_plane_helper_atomic_update(struct drm_plane *plane,
>> +                                              struct drm_atomic_commit 
>> *state)
>>   {
>> -    struct aspeed_gfx *priv = drm_pipe_to_aspeed_gfx(pipe);
>> -    struct drm_crtc *crtc = &pipe->crtc;
>> -    struct drm_framebuffer *fb = pipe->plane.state->fb;
>> +    struct aspeed_gfx *priv = container_of(plane, struct aspeed_gfx, plane);
>
> to_aspeed_gfx(plane->dev)
>

Acknowledged

>> +    struct drm_crtc *crtc = &priv->crtc;
>> +    struct drm_framebuffer *fb = plane->state->fb;
>>      struct drm_pending_vblank_event *event;
>>      struct drm_gem_dma_object *gem;
>>   
>> @@ -190,9 +183,9 @@ static void aspeed_gfx_pipe_update(struct 
>> drm_simple_display_pipe *pipe,
>>      writel(gem->dma_addr, priv->base + CRT_ADDR);
>>   }
>>   
>> -static int aspeed_gfx_enable_vblank(struct drm_simple_display_pipe *pipe)
>> +static int aspeed_gfx_crtc_enable_vblank(struct drm_crtc *crtc)
>>   {
>> -    struct aspeed_gfx *priv = drm_pipe_to_aspeed_gfx(pipe);
>> +    struct aspeed_gfx *priv = container_of(crtc, struct aspeed_gfx, crtc);
>>      u32 reg = readl(priv->base + CRT_CTRL1);
>>   
>>      /* Clear pending VBLANK IRQ */
>> @@ -204,9 +197,9 @@ static int aspeed_gfx_enable_vblank(struct 
>> drm_simple_display_pipe *pipe)
>>      return 0;
>>   }
>>   
>> -static void aspeed_gfx_disable_vblank(struct drm_simple_display_pipe *pipe)
>> +static void aspeed_gfx_crtc_disable_vblank(struct drm_crtc *crtc)
>>   {
>> -    struct aspeed_gfx *priv = drm_pipe_to_aspeed_gfx(pipe);
>> +    struct aspeed_gfx *priv = container_of(crtc, struct aspeed_gfx, crtc);
>>      u32 reg = readl(priv->base + CRT_CTRL1);
>>   
>>      reg &= ~CRT_CTRL_VERTICAL_INTR_EN;
>> @@ -216,12 +209,75 @@ static void aspeed_gfx_disable_vblank(struct 
>> drm_simple_display_pipe *pipe)
>>      writel(reg | CRT_CTRL_VERTICAL_INTR_STS, priv->base + CRT_CTRL1);
>>   }
>>   
>> -static const struct drm_simple_display_pipe_funcs aspeed_gfx_funcs = {
>> -    .enable         = aspeed_gfx_pipe_enable,
>> -    .disable        = aspeed_gfx_pipe_disable,
>> -    .update         = aspeed_gfx_pipe_update,
>> -    .enable_vblank  = aspeed_gfx_enable_vblank,
>> -    .disable_vblank = aspeed_gfx_disable_vblank,
>> +static int aspeed_gfx_plane_helper_atomic_check(struct drm_plane *plane,
>> +                                            struct drm_atomic_commit *state)
>> +{
>> +    struct drm_plane_state *plane_state = 
>> drm_atomic_get_new_plane_state(state, plane);
>> +    struct drm_crtc *crtc = plane_state->crtc;
>> +    struct drm_crtc_state *crtc_state = NULL;
>> +    int ret;
>> +
>> +    if (crtc)
>> +            crtc_state = drm_atomic_get_new_crtc_state(state, crtc);
>> +
>> +    ret = drm_atomic_helper_check_plane_state(plane_state, crtc_state,
>> +                                              DRM_PLANE_NO_SCALING,
>> +                                              DRM_PLANE_NO_SCALING,
>> +                                              false, false);
>> +    return ret;
>> +}
>
> Return directly.
>

OK

>> +
>> +static const struct drm_plane_helper_funcs aspeed_gfx_plane_helper_funcs = {
>> +    .prepare_fb     = drm_gem_plane_helper_prepare_fb,
>> +    .atomic_check   = aspeed_gfx_plane_helper_atomic_check,
>> +    .atomic_update  = aspeed_gfx_plane_helper_atomic_update,
>> +};
>> +
>> +static const struct drm_plane_funcs aspeed_gfx_plane_funcs = {
>> +    .update_plane           = drm_atomic_helper_update_plane,
>> +    .disable_plane          = drm_atomic_helper_disable_plane,
>> +    .destroy                = drm_plane_cleanup,
>> +    .reset                  = drm_atomic_helper_plane_reset,
>> +    .atomic_duplicate_state = drm_atomic_helper_plane_duplicate_state,
>> +    .atomic_destroy_state   = drm_atomic_helper_plane_destroy_state,
>> +};
>> +
>> +static int aspeed_gfx_crtc_helper_atomic_check(struct drm_crtc *crtc,
>> +                                           struct drm_atomic_commit *state)
>> +{
>> +    struct drm_crtc_state *crtc_state = 
>> drm_atomic_get_new_crtc_state(state, crtc);
>> +    int ret;
>> +
>> +    if (!crtc_state->enable)
>> +            goto out;
>> +
>> +    ret = drm_atomic_helper_check_crtc_primary_plane(crtc_state);
>> +    if (ret)
>> +            return ret;
>> +
>> +out:
>> +    return drm_atomic_add_affected_planes(state, crtc);
>> +}
>
> See arcpgu on a possible style improvement.
>

Will do, thanks


> Best regards
> Thomas
>

[ ... ]