diff mbox series

[01/15] drm/i915/plane: warn on non-zero plane offset

Message ID 0988d237e56c56568f035053da8e2e2308a17d3a.1685119007.git.jani.nikula@intel.com (mailing list archive)
State New, archived
Headers show
Series drm/i915: re-enable -Wunused-but-set-variable | expand

Commit Message

Jani Nikula May 26, 2023, 4:37 p.m. UTC 
We assume the plane offset is 0. Warn if it's not. This also fixes a
warn on unused but set variable offset.

Suggested-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
---
 drivers/gpu/drm/i915/display/i9xx_plane.c          | 2 ++
 drivers/gpu/drm/i915/display/skl_universal_plane.c | 1 +
 2 files changed, 3 insertions(+)

Comments

Ville Syrjala May 26, 2023, 4:49 p.m. UTC | #1 
On Fri, May 26, 2023 at 07:37:54PM +0300, Jani Nikula wrote:
> We assume the plane offset is 0. Warn if it's not. This also fixes a
> warn on unused but set variable offset.
> 
> Suggested-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
> Signed-off-by: Jani Nikula <jani.nikula@intel.com>
> ---
>  drivers/gpu/drm/i915/display/i9xx_plane.c          | 2 ++
>  drivers/gpu/drm/i915/display/skl_universal_plane.c | 1 +
>  2 files changed, 3 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/display/i9xx_plane.c b/drivers/gpu/drm/i915/display/i9xx_plane.c
> index 616654adbfb8..b52a681ca85e 100644
> --- a/drivers/gpu/drm/i915/display/i9xx_plane.c
> +++ b/drivers/gpu/drm/i915/display/i9xx_plane.c
> @@ -1037,6 +1037,8 @@ i9xx_get_initial_plane_config(struct intel_crtc *crtc,
>  	}
>  	plane_config->base = base;
>  
> +	drm_WARN_ON(&dev_priv->drm, offset != 0);
> +

The gen2/3 codepath doesn't appear to initialize offset at all.

With that fixed this is
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>

>  	val = intel_de_read(dev_priv, PIPESRC(pipe));
>  	fb->width = REG_FIELD_GET(PIPESRC_WIDTH_MASK, val) + 1;
>  	fb->height = REG_FIELD_GET(PIPESRC_HEIGHT_MASK, val) + 1;
> diff --git a/drivers/gpu/drm/i915/display/skl_universal_plane.c b/drivers/gpu/drm/i915/display/skl_universal_plane.c
> index 36070d86550f..6b01a0b68b97 100644
> --- a/drivers/gpu/drm/i915/display/skl_universal_plane.c
> +++ b/drivers/gpu/drm/i915/display/skl_universal_plane.c
> @@ -2529,6 +2529,7 @@ skl_get_initial_plane_config(struct intel_crtc *crtc,
>  	plane_config->base = base;
>  
>  	offset = intel_de_read(dev_priv, PLANE_OFFSET(pipe, plane_id));
> +	drm_WARN_ON(&dev_priv->drm, offset != 0);
>  
>  	val = intel_de_read(dev_priv, PLANE_SIZE(pipe, plane_id));
>  	fb->height = REG_FIELD_GET(PLANE_HEIGHT_MASK, val) + 1;
> -- 
> 2.39.2
Jani Nikula May 26, 2023, 5:22 p.m. UTC | #2 
On Fri, 26 May 2023, Ville Syrjälä <ville.syrjala@linux.intel.com> wrote:
> On Fri, May 26, 2023 at 07:37:54PM +0300, Jani Nikula wrote:
>> We assume the plane offset is 0. Warn if it's not. This also fixes a
>> warn on unused but set variable offset.
>> 
>> Suggested-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
>> Signed-off-by: Jani Nikula <jani.nikula@intel.com>
>> ---
>>  drivers/gpu/drm/i915/display/i9xx_plane.c          | 2 ++
>>  drivers/gpu/drm/i915/display/skl_universal_plane.c | 1 +
>>  2 files changed, 3 insertions(+)
>> 
>> diff --git a/drivers/gpu/drm/i915/display/i9xx_plane.c b/drivers/gpu/drm/i915/display/i9xx_plane.c
>> index 616654adbfb8..b52a681ca85e 100644
>> --- a/drivers/gpu/drm/i915/display/i9xx_plane.c
>> +++ b/drivers/gpu/drm/i915/display/i9xx_plane.c
>> @@ -1037,6 +1037,8 @@ i9xx_get_initial_plane_config(struct intel_crtc *crtc,
>>  	}
>>  	plane_config->base = base;
>>  
>> +	drm_WARN_ON(&dev_priv->drm, offset != 0);
>> +
>
> The gen2/3 codepath doesn't appear to initialize offset at all.

Right. I wonder why I didn't get a warning about using an uninitialized
variable.

>
> With that fixed this is
> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>

Thanks, v2 sent.


>
>>  	val = intel_de_read(dev_priv, PIPESRC(pipe));
>>  	fb->width = REG_FIELD_GET(PIPESRC_WIDTH_MASK, val) + 1;
>>  	fb->height = REG_FIELD_GET(PIPESRC_HEIGHT_MASK, val) + 1;
>> diff --git a/drivers/gpu/drm/i915/display/skl_universal_plane.c b/drivers/gpu/drm/i915/display/skl_universal_plane.c
>> index 36070d86550f..6b01a0b68b97 100644
>> --- a/drivers/gpu/drm/i915/display/skl_universal_plane.c
>> +++ b/drivers/gpu/drm/i915/display/skl_universal_plane.c
>> @@ -2529,6 +2529,7 @@ skl_get_initial_plane_config(struct intel_crtc *crtc,
>>  	plane_config->base = base;
>>  
>>  	offset = intel_de_read(dev_priv, PLANE_OFFSET(pipe, plane_id));
>> +	drm_WARN_ON(&dev_priv->drm, offset != 0);
>>  
>>  	val = intel_de_read(dev_priv, PLANE_SIZE(pipe, plane_id));
>>  	fb->height = REG_FIELD_GET(PLANE_HEIGHT_MASK, val) + 1;
>> -- 
>> 2.39.2
kernel test robot May 27, 2023, 12:27 a.m. UTC | #3 
Hi Jani,

kernel test robot noticed the following build errors:

[auto build test ERROR on drm-tip/drm-tip]

url:    https://github.com/intel-lab-lkp/linux/commits/Jani-Nikula/drm-i915-plane-warn-on-non-zero-plane-offset/20230527-003951
base:   git://anongit.freedesktop.org/drm/drm-tip drm-tip
patch link:    https://lore.kernel.org/r/0988d237e56c56568f035053da8e2e2308a17d3a.1685119007.git.jani.nikula%40intel.com
patch subject: [Intel-gfx] [PATCH 01/15] drm/i915/plane: warn on non-zero plane offset
config: x86_64-randconfig-x056-20230526 (https://download.01.org/0day-ci/archive/20230527/202305270846.ZA7bj1cg-lkp@intel.com/config)
compiler: clang version 14.0.6 (https://github.com/llvm/llvm-project f28c006a5895fc0e329fe15fead81e37457cb1d1)
reproduce (this is a W=1 build):
        mkdir -p ~/bin
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/intel-lab-lkp/linux/commit/40c3d9e9221e230ab6f0b2e3051b6c4566a1e852
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Jani-Nikula/drm-i915-plane-warn-on-non-zero-plane-offset/20230527-003951
        git checkout 40c3d9e9221e230ab6f0b2e3051b6c4566a1e852
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang ~/bin/make.cross W=1 O=build_dir ARCH=x86_64 olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang ~/bin/make.cross W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash drivers/gpu/drm/i915/

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202305270846.ZA7bj1cg-lkp@intel.com/

All errors (new ones prefixed by >>):

>> drivers/gpu/drm/i915/display/i9xx_plane.c:1027:13: error: variable 'offset' is used uninitialized whenever 'if' condition is false [-Werror,-Wsometimes-uninitialized]
           } else if (DISPLAY_VER(dev_priv) >= 4) {
                      ^~~~~~~~~~~~~~~~~~~~~~~~~~
   drivers/gpu/drm/i915/i915_drv.h:433:27: note: expanded from macro 'DISPLAY_VER'
   #define DISPLAY_VER(i915)       (DISPLAY_RUNTIME_INFO(i915)->ip.ver)
                                   ^
   drivers/gpu/drm/i915/display/i9xx_plane.c:1040:30: note: uninitialized use occurs here
           drm_WARN_ON(&dev_priv->drm, offset != 0);
                                       ^~~~~~
   include/drm/drm_print.h:630:19: note: expanded from macro 'drm_WARN_ON'
           drm_WARN((drm), (x), "%s",                                      \
                            ^
   include/drm/drm_print.h:620:7: note: expanded from macro 'drm_WARN'
           WARN(condition, "%s %s: " format,                               \
                ^~~~~~~~~
   include/asm-generic/bug.h:131:25: note: expanded from macro 'WARN'
           int __ret_warn_on = !!(condition);                              \
                                  ^~~~~~~~~
   drivers/gpu/drm/i915/display/i9xx_plane.c:1027:9: note: remove the 'if' if its condition is always true
           } else if (DISPLAY_VER(dev_priv) >= 4) {
                  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   drivers/gpu/drm/i915/display/i9xx_plane.c:983:23: note: initialize the variable 'offset' to silence this warning
           u32 val, base, offset;
                                ^
                                 = 0
   1 error generated.


vim +1027 drivers/gpu/drm/i915/display/i9xx_plane.c

2a3014490cd18a Dave Airlie   2021-02-05   973  
2a3014490cd18a Dave Airlie   2021-02-05   974  void
2a3014490cd18a Dave Airlie   2021-02-05   975  i9xx_get_initial_plane_config(struct intel_crtc *crtc,
2a3014490cd18a Dave Airlie   2021-02-05   976  			      struct intel_initial_plane_config *plane_config)
2a3014490cd18a Dave Airlie   2021-02-05   977  {
2a3014490cd18a Dave Airlie   2021-02-05   978  	struct drm_device *dev = crtc->base.dev;
2a3014490cd18a Dave Airlie   2021-02-05   979  	struct drm_i915_private *dev_priv = to_i915(dev);
2a3014490cd18a Dave Airlie   2021-02-05   980  	struct intel_plane *plane = to_intel_plane(crtc->base.primary);
2a3014490cd18a Dave Airlie   2021-02-05   981  	enum i9xx_plane_id i9xx_plane = plane->i9xx_plane;
2a3014490cd18a Dave Airlie   2021-02-05   982  	enum pipe pipe;
2a3014490cd18a Dave Airlie   2021-02-05   983  	u32 val, base, offset;
2a3014490cd18a Dave Airlie   2021-02-05   984  	int fourcc, pixel_format;
2a3014490cd18a Dave Airlie   2021-02-05   985  	unsigned int aligned_height;
2a3014490cd18a Dave Airlie   2021-02-05   986  	struct drm_framebuffer *fb;
2a3014490cd18a Dave Airlie   2021-02-05   987  	struct intel_framebuffer *intel_fb;
2a3014490cd18a Dave Airlie   2021-02-05   988  
2a3014490cd18a Dave Airlie   2021-02-05   989  	if (!plane->get_hw_state(plane, &pipe))
2a3014490cd18a Dave Airlie   2021-02-05   990  		return;
2a3014490cd18a Dave Airlie   2021-02-05   991  
2a3014490cd18a Dave Airlie   2021-02-05   992  	drm_WARN_ON(dev, pipe != crtc->pipe);
2a3014490cd18a Dave Airlie   2021-02-05   993  
2a3014490cd18a Dave Airlie   2021-02-05   994  	intel_fb = kzalloc(sizeof(*intel_fb), GFP_KERNEL);
2a3014490cd18a Dave Airlie   2021-02-05   995  	if (!intel_fb) {
2a3014490cd18a Dave Airlie   2021-02-05   996  		drm_dbg_kms(&dev_priv->drm, "failed to alloc fb\n");
2a3014490cd18a Dave Airlie   2021-02-05   997  		return;
2a3014490cd18a Dave Airlie   2021-02-05   998  	}
2a3014490cd18a Dave Airlie   2021-02-05   999  
2a3014490cd18a Dave Airlie   2021-02-05  1000  	fb = &intel_fb->base;
2a3014490cd18a Dave Airlie   2021-02-05  1001  
2a3014490cd18a Dave Airlie   2021-02-05  1002  	fb->dev = dev;
2a3014490cd18a Dave Airlie   2021-02-05  1003  
2a3014490cd18a Dave Airlie   2021-02-05  1004  	val = intel_de_read(dev_priv, DSPCNTR(i9xx_plane));
2a3014490cd18a Dave Airlie   2021-02-05  1005  
005e95377249cb Matt Roper    2021-03-19  1006  	if (DISPLAY_VER(dev_priv) >= 4) {
428cb15d5b0031 Ville Syrjälä 2022-01-21  1007  		if (val & DISP_TILED) {
2a3014490cd18a Dave Airlie   2021-02-05  1008  			plane_config->tiling = I915_TILING_X;
2a3014490cd18a Dave Airlie   2021-02-05  1009  			fb->modifier = I915_FORMAT_MOD_X_TILED;
2a3014490cd18a Dave Airlie   2021-02-05  1010  		}
2a3014490cd18a Dave Airlie   2021-02-05  1011  
428cb15d5b0031 Ville Syrjälä 2022-01-21  1012  		if (val & DISP_ROTATE_180)
2a3014490cd18a Dave Airlie   2021-02-05  1013  			plane_config->rotation = DRM_MODE_ROTATE_180;
2a3014490cd18a Dave Airlie   2021-02-05  1014  	}
2a3014490cd18a Dave Airlie   2021-02-05  1015  
2a3014490cd18a Dave Airlie   2021-02-05  1016  	if (IS_CHERRYVIEW(dev_priv) && pipe == PIPE_B &&
428cb15d5b0031 Ville Syrjälä 2022-01-21  1017  	    val & DISP_MIRROR)
2a3014490cd18a Dave Airlie   2021-02-05  1018  		plane_config->rotation |= DRM_MODE_REFLECT_X;
2a3014490cd18a Dave Airlie   2021-02-05  1019  
428cb15d5b0031 Ville Syrjälä 2022-01-21  1020  	pixel_format = val & DISP_FORMAT_MASK;
2a3014490cd18a Dave Airlie   2021-02-05  1021  	fourcc = i9xx_format_to_fourcc(pixel_format);
2a3014490cd18a Dave Airlie   2021-02-05  1022  	fb->format = drm_format_info(fourcc);
2a3014490cd18a Dave Airlie   2021-02-05  1023  
2a3014490cd18a Dave Airlie   2021-02-05  1024  	if (IS_HASWELL(dev_priv) || IS_BROADWELL(dev_priv)) {
2a3014490cd18a Dave Airlie   2021-02-05  1025  		offset = intel_de_read(dev_priv, DSPOFFSET(i9xx_plane));
428cb15d5b0031 Ville Syrjälä 2022-01-21  1026  		base = intel_de_read(dev_priv, DSPSURF(i9xx_plane)) & DISP_ADDR_MASK;
005e95377249cb Matt Roper    2021-03-19 @1027  	} else if (DISPLAY_VER(dev_priv) >= 4) {
kernel test robot May 27, 2023, 1:50 a.m. UTC | #4 
Hi Jani,

kernel test robot noticed the following build warnings:

[auto build test WARNING on drm-tip/drm-tip]

url:    https://github.com/intel-lab-lkp/linux/commits/Jani-Nikula/drm-i915-plane-warn-on-non-zero-plane-offset/20230527-003951
base:   git://anongit.freedesktop.org/drm/drm-tip drm-tip
patch link:    https://lore.kernel.org/r/0988d237e56c56568f035053da8e2e2308a17d3a.1685119007.git.jani.nikula%40intel.com
patch subject: [Intel-gfx] [PATCH 01/15] drm/i915/plane: warn on non-zero plane offset
config: i386-randconfig-i076-20230526 (https://download.01.org/0day-ci/archive/20230527/202305270919.ttCZVsAy-lkp@intel.com/config)
compiler: clang version 14.0.6 (https://github.com/llvm/llvm-project f28c006a5895fc0e329fe15fead81e37457cb1d1)
reproduce (this is a W=1 build):
        mkdir -p ~/bin
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/intel-lab-lkp/linux/commit/40c3d9e9221e230ab6f0b2e3051b6c4566a1e852
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Jani-Nikula/drm-i915-plane-warn-on-non-zero-plane-offset/20230527-003951
        git checkout 40c3d9e9221e230ab6f0b2e3051b6c4566a1e852
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang ~/bin/make.cross W=1 O=build_dir ARCH=i386 olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang ~/bin/make.cross W=1 O=build_dir ARCH=i386 SHELL=/bin/bash drivers/gpu/drm/i915/

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202305270919.ttCZVsAy-lkp@intel.com/

All warnings (new ones prefixed by >>):

>> drivers/gpu/drm/i915/display/i9xx_plane.c:1027:13: warning: variable 'offset' is used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized]
           } else if (DISPLAY_VER(dev_priv) >= 4) {
                      ^~~~~~~~~~~~~~~~~~~~~~~~~~
   drivers/gpu/drm/i915/i915_drv.h:433:27: note: expanded from macro 'DISPLAY_VER'
   #define DISPLAY_VER(i915)       (DISPLAY_RUNTIME_INFO(i915)->ip.ver)
                                   ^
   drivers/gpu/drm/i915/display/i9xx_plane.c:1040:30: note: uninitialized use occurs here
           drm_WARN_ON(&dev_priv->drm, offset != 0);
                                       ^~~~~~
   include/drm/drm_print.h:630:19: note: expanded from macro 'drm_WARN_ON'
           drm_WARN((drm), (x), "%s",                                      \
                            ^
   include/drm/drm_print.h:620:7: note: expanded from macro 'drm_WARN'
           WARN(condition, "%s %s: " format,                               \
                ^~~~~~~~~
   include/asm-generic/bug.h:131:25: note: expanded from macro 'WARN'
           int __ret_warn_on = !!(condition);                              \
                                  ^~~~~~~~~
   drivers/gpu/drm/i915/display/i9xx_plane.c:1027:9: note: remove the 'if' if its condition is always true
           } else if (DISPLAY_VER(dev_priv) >= 4) {
                  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   drivers/gpu/drm/i915/display/i9xx_plane.c:983:23: note: initialize the variable 'offset' to silence this warning
           u32 val, base, offset;
                                ^
                                 = 0
   1 warning generated.


vim +1027 drivers/gpu/drm/i915/display/i9xx_plane.c

2a3014490cd18a Dave Airlie   2021-02-05   973  
2a3014490cd18a Dave Airlie   2021-02-05   974  void
2a3014490cd18a Dave Airlie   2021-02-05   975  i9xx_get_initial_plane_config(struct intel_crtc *crtc,
2a3014490cd18a Dave Airlie   2021-02-05   976  			      struct intel_initial_plane_config *plane_config)
2a3014490cd18a Dave Airlie   2021-02-05   977  {
2a3014490cd18a Dave Airlie   2021-02-05   978  	struct drm_device *dev = crtc->base.dev;
2a3014490cd18a Dave Airlie   2021-02-05   979  	struct drm_i915_private *dev_priv = to_i915(dev);
2a3014490cd18a Dave Airlie   2021-02-05   980  	struct intel_plane *plane = to_intel_plane(crtc->base.primary);
2a3014490cd18a Dave Airlie   2021-02-05   981  	enum i9xx_plane_id i9xx_plane = plane->i9xx_plane;
2a3014490cd18a Dave Airlie   2021-02-05   982  	enum pipe pipe;
2a3014490cd18a Dave Airlie   2021-02-05   983  	u32 val, base, offset;
2a3014490cd18a Dave Airlie   2021-02-05   984  	int fourcc, pixel_format;
2a3014490cd18a Dave Airlie   2021-02-05   985  	unsigned int aligned_height;
2a3014490cd18a Dave Airlie   2021-02-05   986  	struct drm_framebuffer *fb;
2a3014490cd18a Dave Airlie   2021-02-05   987  	struct intel_framebuffer *intel_fb;
2a3014490cd18a Dave Airlie   2021-02-05   988  
2a3014490cd18a Dave Airlie   2021-02-05   989  	if (!plane->get_hw_state(plane, &pipe))
2a3014490cd18a Dave Airlie   2021-02-05   990  		return;
2a3014490cd18a Dave Airlie   2021-02-05   991  
2a3014490cd18a Dave Airlie   2021-02-05   992  	drm_WARN_ON(dev, pipe != crtc->pipe);
2a3014490cd18a Dave Airlie   2021-02-05   993  
2a3014490cd18a Dave Airlie   2021-02-05   994  	intel_fb = kzalloc(sizeof(*intel_fb), GFP_KERNEL);
2a3014490cd18a Dave Airlie   2021-02-05   995  	if (!intel_fb) {
2a3014490cd18a Dave Airlie   2021-02-05   996  		drm_dbg_kms(&dev_priv->drm, "failed to alloc fb\n");
2a3014490cd18a Dave Airlie   2021-02-05   997  		return;
2a3014490cd18a Dave Airlie   2021-02-05   998  	}
2a3014490cd18a Dave Airlie   2021-02-05   999  
2a3014490cd18a Dave Airlie   2021-02-05  1000  	fb = &intel_fb->base;
2a3014490cd18a Dave Airlie   2021-02-05  1001  
2a3014490cd18a Dave Airlie   2021-02-05  1002  	fb->dev = dev;
2a3014490cd18a Dave Airlie   2021-02-05  1003  
2a3014490cd18a Dave Airlie   2021-02-05  1004  	val = intel_de_read(dev_priv, DSPCNTR(i9xx_plane));
2a3014490cd18a Dave Airlie   2021-02-05  1005  
005e95377249cb Matt Roper    2021-03-19  1006  	if (DISPLAY_VER(dev_priv) >= 4) {
428cb15d5b0031 Ville Syrjälä 2022-01-21  1007  		if (val & DISP_TILED) {
2a3014490cd18a Dave Airlie   2021-02-05  1008  			plane_config->tiling = I915_TILING_X;
2a3014490cd18a Dave Airlie   2021-02-05  1009  			fb->modifier = I915_FORMAT_MOD_X_TILED;
2a3014490cd18a Dave Airlie   2021-02-05  1010  		}
2a3014490cd18a Dave Airlie   2021-02-05  1011  
428cb15d5b0031 Ville Syrjälä 2022-01-21  1012  		if (val & DISP_ROTATE_180)
2a3014490cd18a Dave Airlie   2021-02-05  1013  			plane_config->rotation = DRM_MODE_ROTATE_180;
2a3014490cd18a Dave Airlie   2021-02-05  1014  	}
2a3014490cd18a Dave Airlie   2021-02-05  1015  
2a3014490cd18a Dave Airlie   2021-02-05  1016  	if (IS_CHERRYVIEW(dev_priv) && pipe == PIPE_B &&
428cb15d5b0031 Ville Syrjälä 2022-01-21  1017  	    val & DISP_MIRROR)
2a3014490cd18a Dave Airlie   2021-02-05  1018  		plane_config->rotation |= DRM_MODE_REFLECT_X;
2a3014490cd18a Dave Airlie   2021-02-05  1019  
428cb15d5b0031 Ville Syrjälä 2022-01-21  1020  	pixel_format = val & DISP_FORMAT_MASK;
2a3014490cd18a Dave Airlie   2021-02-05  1021  	fourcc = i9xx_format_to_fourcc(pixel_format);
2a3014490cd18a Dave Airlie   2021-02-05  1022  	fb->format = drm_format_info(fourcc);
2a3014490cd18a Dave Airlie   2021-02-05  1023  
2a3014490cd18a Dave Airlie   2021-02-05  1024  	if (IS_HASWELL(dev_priv) || IS_BROADWELL(dev_priv)) {
2a3014490cd18a Dave Airlie   2021-02-05  1025  		offset = intel_de_read(dev_priv, DSPOFFSET(i9xx_plane));
428cb15d5b0031 Ville Syrjälä 2022-01-21  1026  		base = intel_de_read(dev_priv, DSPSURF(i9xx_plane)) & DISP_ADDR_MASK;
005e95377249cb Matt Roper    2021-03-19 @1027  	} else if (DISPLAY_VER(dev_priv) >= 4) {
Dan Carpenter May 29, 2023, 9:24 a.m. UTC | #5 
Hi Jani,

kernel test robot noticed the following build warnings:

url:    https://github.com/intel-lab-lkp/linux/commits/Jani-Nikula/drm-i915-plane-warn-on-non-zero-plane-offset/20230527-003951
base:   git://anongit.freedesktop.org/drm/drm-tip drm-tip
patch link:    https://lore.kernel.org/r/0988d237e56c56568f035053da8e2e2308a17d3a.1685119007.git.jani.nikula%40intel.com
patch subject: [Intel-gfx] [PATCH 01/15] drm/i915/plane: warn on non-zero plane offset
config: x86_64-randconfig-m031-20230526 (https://download.01.org/0day-ci/archive/20230528/202305280453.8yzCMS2i-lkp@intel.com/config)
compiler: gcc-11 (Debian 11.3.0-12) 11.3.0

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>
| Reported-by: Dan Carpenter <error27@gmail.com>
| Closes: https://lore.kernel.org/r/202305280453.8yzCMS2i-lkp@intel.com/

smatch warnings:
drivers/gpu/drm/i915/display/i9xx_plane.c:1040 i9xx_get_initial_plane_config() error: uninitialized symbol 'offset'.

vim +/offset +1040 drivers/gpu/drm/i915/display/i9xx_plane.c

2a3014490cd18a Dave Airlie   2021-02-05   974  void
2a3014490cd18a Dave Airlie   2021-02-05   975  i9xx_get_initial_plane_config(struct intel_crtc *crtc,
2a3014490cd18a Dave Airlie   2021-02-05   976  			      struct intel_initial_plane_config *plane_config)
2a3014490cd18a Dave Airlie   2021-02-05   977  {
2a3014490cd18a Dave Airlie   2021-02-05   978  	struct drm_device *dev = crtc->base.dev;
2a3014490cd18a Dave Airlie   2021-02-05   979  	struct drm_i915_private *dev_priv = to_i915(dev);
2a3014490cd18a Dave Airlie   2021-02-05   980  	struct intel_plane *plane = to_intel_plane(crtc->base.primary);
2a3014490cd18a Dave Airlie   2021-02-05   981  	enum i9xx_plane_id i9xx_plane = plane->i9xx_plane;
2a3014490cd18a Dave Airlie   2021-02-05   982  	enum pipe pipe;
2a3014490cd18a Dave Airlie   2021-02-05   983  	u32 val, base, offset;
2a3014490cd18a Dave Airlie   2021-02-05   984  	int fourcc, pixel_format;
2a3014490cd18a Dave Airlie   2021-02-05   985  	unsigned int aligned_height;
2a3014490cd18a Dave Airlie   2021-02-05   986  	struct drm_framebuffer *fb;
2a3014490cd18a Dave Airlie   2021-02-05   987  	struct intel_framebuffer *intel_fb;
2a3014490cd18a Dave Airlie   2021-02-05   988  
2a3014490cd18a Dave Airlie   2021-02-05   989  	if (!plane->get_hw_state(plane, &pipe))
2a3014490cd18a Dave Airlie   2021-02-05   990  		return;
2a3014490cd18a Dave Airlie   2021-02-05   991  
2a3014490cd18a Dave Airlie   2021-02-05   992  	drm_WARN_ON(dev, pipe != crtc->pipe);
2a3014490cd18a Dave Airlie   2021-02-05   993  
2a3014490cd18a Dave Airlie   2021-02-05   994  	intel_fb = kzalloc(sizeof(*intel_fb), GFP_KERNEL);
2a3014490cd18a Dave Airlie   2021-02-05   995  	if (!intel_fb) {
2a3014490cd18a Dave Airlie   2021-02-05   996  		drm_dbg_kms(&dev_priv->drm, "failed to alloc fb\n");
2a3014490cd18a Dave Airlie   2021-02-05   997  		return;
2a3014490cd18a Dave Airlie   2021-02-05   998  	}
2a3014490cd18a Dave Airlie   2021-02-05   999  
2a3014490cd18a Dave Airlie   2021-02-05  1000  	fb = &intel_fb->base;
2a3014490cd18a Dave Airlie   2021-02-05  1001  
2a3014490cd18a Dave Airlie   2021-02-05  1002  	fb->dev = dev;
2a3014490cd18a Dave Airlie   2021-02-05  1003  
2a3014490cd18a Dave Airlie   2021-02-05  1004  	val = intel_de_read(dev_priv, DSPCNTR(i9xx_plane));
2a3014490cd18a Dave Airlie   2021-02-05  1005  
005e95377249cb Matt Roper    2021-03-19  1006  	if (DISPLAY_VER(dev_priv) >= 4) {
428cb15d5b0031 Ville Syrjälä 2022-01-21  1007  		if (val & DISP_TILED) {
2a3014490cd18a Dave Airlie   2021-02-05  1008  			plane_config->tiling = I915_TILING_X;
2a3014490cd18a Dave Airlie   2021-02-05  1009  			fb->modifier = I915_FORMAT_MOD_X_TILED;
2a3014490cd18a Dave Airlie   2021-02-05  1010  		}
2a3014490cd18a Dave Airlie   2021-02-05  1011  
428cb15d5b0031 Ville Syrjälä 2022-01-21  1012  		if (val & DISP_ROTATE_180)
2a3014490cd18a Dave Airlie   2021-02-05  1013  			plane_config->rotation = DRM_MODE_ROTATE_180;
2a3014490cd18a Dave Airlie   2021-02-05  1014  	}
2a3014490cd18a Dave Airlie   2021-02-05  1015  
2a3014490cd18a Dave Airlie   2021-02-05  1016  	if (IS_CHERRYVIEW(dev_priv) && pipe == PIPE_B &&
428cb15d5b0031 Ville Syrjälä 2022-01-21  1017  	    val & DISP_MIRROR)
2a3014490cd18a Dave Airlie   2021-02-05  1018  		plane_config->rotation |= DRM_MODE_REFLECT_X;
2a3014490cd18a Dave Airlie   2021-02-05  1019  
428cb15d5b0031 Ville Syrjälä 2022-01-21  1020  	pixel_format = val & DISP_FORMAT_MASK;
2a3014490cd18a Dave Airlie   2021-02-05  1021  	fourcc = i9xx_format_to_fourcc(pixel_format);
2a3014490cd18a Dave Airlie   2021-02-05  1022  	fb->format = drm_format_info(fourcc);
2a3014490cd18a Dave Airlie   2021-02-05  1023  
2a3014490cd18a Dave Airlie   2021-02-05  1024  	if (IS_HASWELL(dev_priv) || IS_BROADWELL(dev_priv)) {
2a3014490cd18a Dave Airlie   2021-02-05  1025  		offset = intel_de_read(dev_priv, DSPOFFSET(i9xx_plane));
428cb15d5b0031 Ville Syrjälä 2022-01-21  1026  		base = intel_de_read(dev_priv, DSPSURF(i9xx_plane)) & DISP_ADDR_MASK;
005e95377249cb Matt Roper    2021-03-19  1027  	} else if (DISPLAY_VER(dev_priv) >= 4) {
2a3014490cd18a Dave Airlie   2021-02-05  1028  		if (plane_config->tiling)
2a3014490cd18a Dave Airlie   2021-02-05  1029  			offset = intel_de_read(dev_priv,
2a3014490cd18a Dave Airlie   2021-02-05  1030  					       DSPTILEOFF(i9xx_plane));
2a3014490cd18a Dave Airlie   2021-02-05  1031  		else
2a3014490cd18a Dave Airlie   2021-02-05  1032  			offset = intel_de_read(dev_priv,
2a3014490cd18a Dave Airlie   2021-02-05  1033  					       DSPLINOFF(i9xx_plane));
428cb15d5b0031 Ville Syrjälä 2022-01-21  1034  		base = intel_de_read(dev_priv, DSPSURF(i9xx_plane)) & DISP_ADDR_MASK;
2a3014490cd18a Dave Airlie   2021-02-05  1035  	} else {
2a3014490cd18a Dave Airlie   2021-02-05  1036  		base = intel_de_read(dev_priv, DSPADDR(i9xx_plane));

offset not initialized on this path.

2a3014490cd18a Dave Airlie   2021-02-05  1037  	}
2a3014490cd18a Dave Airlie   2021-02-05  1038  	plane_config->base = base;
2a3014490cd18a Dave Airlie   2021-02-05  1039  
40c3d9e9221e23 Jani Nikula   2023-05-26 @1040  	drm_WARN_ON(&dev_priv->drm, offset != 0);
Jani Nikula May 29, 2023, 10:04 a.m. UTC | #6 
On Mon, 29 May 2023, Dan Carpenter <dan.carpenter@linaro.org> wrote:
> Hi Jani,
>
> kernel test robot noticed the following build warnings:

Thanks, v2 already on the list:

https://patchwork.freedesktop.org/patch/msgid/20230526172218.1597394-1-jani.nikula@intel.com


>
> url:    https://github.com/intel-lab-lkp/linux/commits/Jani-Nikula/drm-i915-plane-warn-on-non-zero-plane-offset/20230527-003951
> base:   git://anongit.freedesktop.org/drm/drm-tip drm-tip
> patch link:    https://lore.kernel.org/r/0988d237e56c56568f035053da8e2e2308a17d3a.1685119007.git.jani.nikula%40intel.com
> patch subject: [Intel-gfx] [PATCH 01/15] drm/i915/plane: warn on non-zero plane offset
> config: x86_64-randconfig-m031-20230526 (https://download.01.org/0day-ci/archive/20230528/202305280453.8yzCMS2i-lkp@intel.com/config)
> compiler: gcc-11 (Debian 11.3.0-12) 11.3.0
>
> If you fix the issue, kindly add following tag where applicable
> | Reported-by: kernel test robot <lkp@intel.com>
> | Reported-by: Dan Carpenter <error27@gmail.com>
> | Closes: https://lore.kernel.org/r/202305280453.8yzCMS2i-lkp@intel.com/
>
> smatch warnings:
> drivers/gpu/drm/i915/display/i9xx_plane.c:1040 i9xx_get_initial_plane_config() error: uninitialized symbol 'offset'.
>
> vim +/offset +1040 drivers/gpu/drm/i915/display/i9xx_plane.c
>
> 2a3014490cd18a Dave Airlie   2021-02-05   974  void
> 2a3014490cd18a Dave Airlie   2021-02-05   975  i9xx_get_initial_plane_config(struct intel_crtc *crtc,
> 2a3014490cd18a Dave Airlie   2021-02-05   976  			      struct intel_initial_plane_config *plane_config)
> 2a3014490cd18a Dave Airlie   2021-02-05   977  {
> 2a3014490cd18a Dave Airlie   2021-02-05   978  	struct drm_device *dev = crtc->base.dev;
> 2a3014490cd18a Dave Airlie   2021-02-05   979  	struct drm_i915_private *dev_priv = to_i915(dev);
> 2a3014490cd18a Dave Airlie   2021-02-05   980  	struct intel_plane *plane = to_intel_plane(crtc->base.primary);
> 2a3014490cd18a Dave Airlie   2021-02-05   981  	enum i9xx_plane_id i9xx_plane = plane->i9xx_plane;
> 2a3014490cd18a Dave Airlie   2021-02-05   982  	enum pipe pipe;
> 2a3014490cd18a Dave Airlie   2021-02-05   983  	u32 val, base, offset;
> 2a3014490cd18a Dave Airlie   2021-02-05   984  	int fourcc, pixel_format;
> 2a3014490cd18a Dave Airlie   2021-02-05   985  	unsigned int aligned_height;
> 2a3014490cd18a Dave Airlie   2021-02-05   986  	struct drm_framebuffer *fb;
> 2a3014490cd18a Dave Airlie   2021-02-05   987  	struct intel_framebuffer *intel_fb;
> 2a3014490cd18a Dave Airlie   2021-02-05   988  
> 2a3014490cd18a Dave Airlie   2021-02-05   989  	if (!plane->get_hw_state(plane, &pipe))
> 2a3014490cd18a Dave Airlie   2021-02-05   990  		return;
> 2a3014490cd18a Dave Airlie   2021-02-05   991  
> 2a3014490cd18a Dave Airlie   2021-02-05   992  	drm_WARN_ON(dev, pipe != crtc->pipe);
> 2a3014490cd18a Dave Airlie   2021-02-05   993  
> 2a3014490cd18a Dave Airlie   2021-02-05   994  	intel_fb = kzalloc(sizeof(*intel_fb), GFP_KERNEL);
> 2a3014490cd18a Dave Airlie   2021-02-05   995  	if (!intel_fb) {
> 2a3014490cd18a Dave Airlie   2021-02-05   996  		drm_dbg_kms(&dev_priv->drm, "failed to alloc fb\n");
> 2a3014490cd18a Dave Airlie   2021-02-05   997  		return;
> 2a3014490cd18a Dave Airlie   2021-02-05   998  	}
> 2a3014490cd18a Dave Airlie   2021-02-05   999  
> 2a3014490cd18a Dave Airlie   2021-02-05  1000  	fb = &intel_fb->base;
> 2a3014490cd18a Dave Airlie   2021-02-05  1001  
> 2a3014490cd18a Dave Airlie   2021-02-05  1002  	fb->dev = dev;
> 2a3014490cd18a Dave Airlie   2021-02-05  1003  
> 2a3014490cd18a Dave Airlie   2021-02-05  1004  	val = intel_de_read(dev_priv, DSPCNTR(i9xx_plane));
> 2a3014490cd18a Dave Airlie   2021-02-05  1005  
> 005e95377249cb Matt Roper    2021-03-19  1006  	if (DISPLAY_VER(dev_priv) >= 4) {
> 428cb15d5b0031 Ville Syrjälä 2022-01-21  1007  		if (val & DISP_TILED) {
> 2a3014490cd18a Dave Airlie   2021-02-05  1008  			plane_config->tiling = I915_TILING_X;
> 2a3014490cd18a Dave Airlie   2021-02-05  1009  			fb->modifier = I915_FORMAT_MOD_X_TILED;
> 2a3014490cd18a Dave Airlie   2021-02-05  1010  		}
> 2a3014490cd18a Dave Airlie   2021-02-05  1011  
> 428cb15d5b0031 Ville Syrjälä 2022-01-21  1012  		if (val & DISP_ROTATE_180)
> 2a3014490cd18a Dave Airlie   2021-02-05  1013  			plane_config->rotation = DRM_MODE_ROTATE_180;
> 2a3014490cd18a Dave Airlie   2021-02-05  1014  	}
> 2a3014490cd18a Dave Airlie   2021-02-05  1015  
> 2a3014490cd18a Dave Airlie   2021-02-05  1016  	if (IS_CHERRYVIEW(dev_priv) && pipe == PIPE_B &&
> 428cb15d5b0031 Ville Syrjälä 2022-01-21  1017  	    val & DISP_MIRROR)
> 2a3014490cd18a Dave Airlie   2021-02-05  1018  		plane_config->rotation |= DRM_MODE_REFLECT_X;
> 2a3014490cd18a Dave Airlie   2021-02-05  1019  
> 428cb15d5b0031 Ville Syrjälä 2022-01-21  1020  	pixel_format = val & DISP_FORMAT_MASK;
> 2a3014490cd18a Dave Airlie   2021-02-05  1021  	fourcc = i9xx_format_to_fourcc(pixel_format);
> 2a3014490cd18a Dave Airlie   2021-02-05  1022  	fb->format = drm_format_info(fourcc);
> 2a3014490cd18a Dave Airlie   2021-02-05  1023  
> 2a3014490cd18a Dave Airlie   2021-02-05  1024  	if (IS_HASWELL(dev_priv) || IS_BROADWELL(dev_priv)) {
> 2a3014490cd18a Dave Airlie   2021-02-05  1025  		offset = intel_de_read(dev_priv, DSPOFFSET(i9xx_plane));
> 428cb15d5b0031 Ville Syrjälä 2022-01-21  1026  		base = intel_de_read(dev_priv, DSPSURF(i9xx_plane)) & DISP_ADDR_MASK;
> 005e95377249cb Matt Roper    2021-03-19  1027  	} else if (DISPLAY_VER(dev_priv) >= 4) {
> 2a3014490cd18a Dave Airlie   2021-02-05  1028  		if (plane_config->tiling)
> 2a3014490cd18a Dave Airlie   2021-02-05  1029  			offset = intel_de_read(dev_priv,
> 2a3014490cd18a Dave Airlie   2021-02-05  1030  					       DSPTILEOFF(i9xx_plane));
> 2a3014490cd18a Dave Airlie   2021-02-05  1031  		else
> 2a3014490cd18a Dave Airlie   2021-02-05  1032  			offset = intel_de_read(dev_priv,
> 2a3014490cd18a Dave Airlie   2021-02-05  1033  					       DSPLINOFF(i9xx_plane));
> 428cb15d5b0031 Ville Syrjälä 2022-01-21  1034  		base = intel_de_read(dev_priv, DSPSURF(i9xx_plane)) & DISP_ADDR_MASK;
> 2a3014490cd18a Dave Airlie   2021-02-05  1035  	} else {
> 2a3014490cd18a Dave Airlie   2021-02-05  1036  		base = intel_de_read(dev_priv, DSPADDR(i9xx_plane));
>
> offset not initialized on this path.
>
> 2a3014490cd18a Dave Airlie   2021-02-05  1037  	}
> 2a3014490cd18a Dave Airlie   2021-02-05  1038  	plane_config->base = base;
> 2a3014490cd18a Dave Airlie   2021-02-05  1039  
> 40c3d9e9221e23 Jani Nikula   2023-05-26 @1040  	drm_WARN_ON(&dev_priv->drm, offset != 0);
diff mbox series

Patch

diff --git a/drivers/gpu/drm/i915/display/i9xx_plane.c b/drivers/gpu/drm/i915/display/i9xx_plane.c
index 616654adbfb8..b52a681ca85e 100644
--- a/drivers/gpu/drm/i915/display/i9xx_plane.c
+++ b/drivers/gpu/drm/i915/display/i9xx_plane.c
@@ -1037,6 +1037,8 @@  i9xx_get_initial_plane_config(struct intel_crtc *crtc,
 	}
 	plane_config->base = base;
 
+	drm_WARN_ON(&dev_priv->drm, offset != 0);
+
 	val = intel_de_read(dev_priv, PIPESRC(pipe));
 	fb->width = REG_FIELD_GET(PIPESRC_WIDTH_MASK, val) + 1;
 	fb->height = REG_FIELD_GET(PIPESRC_HEIGHT_MASK, val) + 1;
diff --git a/drivers/gpu/drm/i915/display/skl_universal_plane.c b/drivers/gpu/drm/i915/display/skl_universal_plane.c
index 36070d86550f..6b01a0b68b97 100644
--- a/drivers/gpu/drm/i915/display/skl_universal_plane.c
+++ b/drivers/gpu/drm/i915/display/skl_universal_plane.c
@@ -2529,6 +2529,7 @@  skl_get_initial_plane_config(struct intel_crtc *crtc,
 	plane_config->base = base;
 
 	offset = intel_de_read(dev_priv, PLANE_OFFSET(pipe, plane_id));
+	drm_WARN_ON(&dev_priv->drm, offset != 0);
 
 	val = intel_de_read(dev_priv, PLANE_SIZE(pipe, plane_id));
 	fb->height = REG_FIELD_GET(PLANE_HEIGHT_MASK, val) + 1;