Re: [RFC PATCH v2 1/3] drm/fourcc: Add 'bpp' field for formats with non-integer bytes-per-pixel
On Wed, Sep 12, 2018 at 5:27 PM, Liviu Dudau wrote: > On Mon, Sep 10, 2018 at 09:53:25PM +0200, Daniel Vetter wrote: >> On Mon, Sep 10, 2018 at 09:50:03AM +0100, Brian Starkey wrote: >> > Hi, >> > >> > On Fri, Sep 07, 2018 at 09:28:44PM +0200, Daniel Vetter wrote: >> > > On Fri, Sep 07, 2018 at 01:45:36PM +0100, Brian Starkey wrote: >> > > > Hi Daniel, >> > > > >> > > > On Fri, Aug 31, 2018 at 10:17:30AM +0200, Daniel Vetter wrote: >> > > > > On Thu, Aug 23, 2018 at 04:23:41PM +0100, Brian Starkey wrote: >> > > > > > Some formats have a non-integer number of bytes per pixel, which >> > > > > > can't >> > > > > > be handled with the existing 'cpp' field in drm_format_info. To >> > > > > > handle >> > > > > > these formats, add a 'bpp' field, which is only used if cpp[0] == >> > > > > > 0. >> > > > > > >> > > > > > This updates all the users of format->cpp in the core DRM code, >> > > > > > converting them to use a new function to get the bits-per-pixel >> > > > > > for any >> > > > > > format. >> > > > > > >> > > > > > It's assumed that drivers will use the 'bpp' field when they add >> > > > > > support >> > > > > > for pixel formats with non-integer bytes-per-pixel. >> > > > > > >> > > > > > Signed-off-by: Brian Starkey >> > > > > >> > > > > I assume you still require that stuff is eventually aligned to >> > > > > bytes? In >> > > > > that case, can we subsume this into the tile work Alex is doing? It's >> > > > > essentially just another special case of having storage-size units >> > > > > measured in bytes which span more than 1x1 pixel. And I kinda don't >> > > > > want a >> > > > > metric pile of special cases here in the format code, because that >> > > > > just >> > > > > means every driver handles a different subset, with different bugs. >> > > > > -Daniel >> > > > >> > > > Sorry for the delay, been struggling to free some cycles to think >> > > > about this. >> > > > >> > > > I'm not sure how to pull this in with the tiling stuff. In the AFBC >> > > > case then our AFBC superblocks are always nice round numbers (256 >> > > > pixels), and so it does end up being a multiple of bytes. >> > > > >> > > > However, AFBC supports different superblock sizes, so picking just one >> > > > doesn't really work out, and putting AFBC in the core format table >> > > > which reflects AFBC doesn't seem good. >> > > > >> > > > We could make something up (e.g. call these formats "tiled" with 2x4 >> > > > tiles, which guarantees a multiple of 8), but it would be an >> > > > arbitrarily-selected lie, which often seems to spell trouble. If we >> > > > did do that, would you re-define cpp as "bytes-per-tile"? Otherwise >> > > > we still need to add a new field anyway. >> > > > >> > > > What's the pile of special cases you're worried about? The helper I've >> > > > added here means that drivers which need to care can use one API and >> > > > not implement their own bugs. >> > > >> > > I'm confused ... the new bits-per-pixel stuff you're adding here is for >> > > yuv formats, not afbc. I'm just suggesting we have only 1 way of >> > > describing such formats that need more descriptive power than cpp, >> > > whether >> > > they have some kind of pixel-groups or small tiles. >> > >> > Well, not really. The three formats which have non-integer cpp are: >> > DRM_FORMAT_VUY101010, DRM_FORMAT_YUV420_8BIT and >> > DRM_FORMAT_YUV420_10BIT. These formats are only valid with non-linear >> > modifiers (no linear encoding is defined). Mali only supports them >> > with AFBC. >> > >> > The formats themselves have no notion of tiling or grouping - the >> > modifier adds that. I'm not aware of any non-AFBC uses of these >> > formats, so I don't want to "make up" a small-tile layout restriction >> > for them. >> >> Ah, I missed that. >> >> > > For very special stuff like afbc you need to validate in the driver >> > > anyway, too complicated. So I have no idea why you bring this up here? >> > >> > Sure, we can just let drivers provide their own format_info's for >> > these, if that's what you prefer. The core format checking code can >> > error out if it ever encounters them. >> >> It's format_info we're talking about. What I mean is that you just set all >> these to 0 and let the format_info code ignore it. And then having a >> bespoke drm_format_check_afbc helper function or similar, which checks all >> the layout restrictions of afbc. >> >> I still maintain that bpp and tile_size are equavalent, and we really >> don't need both. Both are defacto a form of numerator/denumerator. If you >> don't like that you have to introduce "fake" tiles for afbc, then we can >> rename tile_size to numerator and tile_h/w to denumerator_h/w. Doesn't >> change one bit of the math. bpp simply hardcodes a denumerator of 8, and I >> don't see why we need that special case. Except if you love to write >> redundant self tests for all the math :-) > > My $.02 worth of thoughts: > > I get the fact that Daniel doesn't like us to add 3 new variables into >
Re: [RFC PATCH v2 1/3] drm/fourcc: Add 'bpp' field for formats with non-integer bytes-per-pixel
On Wed, Sep 12, 2018 at 3:52 PM, Brian Starkey wrote: > On Mon, Sep 10, 2018 at 09:53:25PM +0200, Daniel Vetter wrote: >> >> On Mon, Sep 10, 2018 at 09:50:03AM +0100, Brian Starkey wrote: >>> >>> Hi, >>> >>> On Fri, Sep 07, 2018 at 09:28:44PM +0200, Daniel Vetter wrote: >>> > On Fri, Sep 07, 2018 at 01:45:36PM +0100, Brian Starkey wrote: >>> > > Hi Daniel, >>> > > >>> > > On Fri, Aug 31, 2018 at 10:17:30AM +0200, Daniel Vetter wrote: >>> > > > On Thu, Aug 23, 2018 at 04:23:41PM +0100, Brian Starkey wrote: >>> > > > > Some formats have a non-integer number of bytes per pixel, which >>> > > > > can't >>> > > > > be handled with the existing 'cpp' field in drm_format_info. To >>> > > > > handle >>> > > > > these formats, add a 'bpp' field, which is only used if cpp[0] == >>> > > > > 0. >>> > > > > >>> > > > > This updates all the users of format->cpp in the core DRM code, >>> > > > > converting them to use a new function to get the bits-per-pixel >>> > > > > for any >>> > > > > format. >>> > > > > >>> > > > > It's assumed that drivers will use the 'bpp' field when they add >>> > > > > support >>> > > > > for pixel formats with non-integer bytes-per-pixel. >>> > > > > >>> > > > > Signed-off-by: Brian Starkey >>> > > > >>> > > > I assume you still require that stuff is eventually aligned to >>> > > > bytes? In >>> > > > that case, can we subsume this into the tile work Alex is doing? >>> > > > It's >>> > > > essentially just another special case of having storage-size units >>> > > > measured in bytes which span more than 1x1 pixel. And I kinda don't >>> > > > want a >>> > > > metric pile of special cases here in the format code, because that >>> > > > just >>> > > > means every driver handles a different subset, with different bugs. >>> > > > -Daniel >>> > > >>> > > Sorry for the delay, been struggling to free some cycles to think >>> > > about this. >>> > > >>> > > I'm not sure how to pull this in with the tiling stuff. In the AFBC >>> > > case then our AFBC superblocks are always nice round numbers (256 >>> > > pixels), and so it does end up being a multiple of bytes. >>> > > >>> > > However, AFBC supports different superblock sizes, so picking just >>> > > one >>> > > doesn't really work out, and putting AFBC in the core format table >>> > > which reflects AFBC doesn't seem good. >>> > > >>> > > We could make something up (e.g. call these formats "tiled" with 2x4 >>> > > tiles, which guarantees a multiple of 8), but it would be an >>> > > arbitrarily-selected lie, which often seems to spell trouble. If we >>> > > did do that, would you re-define cpp as "bytes-per-tile"? Otherwise >>> > > we still need to add a new field anyway. >>> > > >>> > > What's the pile of special cases you're worried about? The helper >>> > > I've >>> > > added here means that drivers which need to care can use one API and >>> > > not implement their own bugs. >>> > >>> > I'm confused ... the new bits-per-pixel stuff you're adding here is for >>> > yuv formats, not afbc. I'm just suggesting we have only 1 way of >>> > describing such formats that need more descriptive power than cpp, >>> > whether >>> > they have some kind of pixel-groups or small tiles. >>> >>> Well, not really. The three formats which have non-integer cpp are: >>> DRM_FORMAT_VUY101010, DRM_FORMAT_YUV420_8BIT and >>> DRM_FORMAT_YUV420_10BIT. These formats are only valid with non-linear >>> modifiers (no linear encoding is defined). Mali only supports them >>> with AFBC. >>> >>> The formats themselves have no notion of tiling or grouping - the >>> modifier adds that. I'm not aware of any non-AFBC uses of these >>> formats, so I don't want to "make up" a small-tile layout restriction >>> for them. >> >> >> Ah, I missed that. >> >>> > For very special stuff like afbc you need to validate in the driver >>> > anyway, too complicated. So I have no idea why you bring this up here? >>> >>> Sure, we can just let drivers provide their own format_info's for >>> these, if that's what you prefer. The core format checking code can >>> error out if it ever encounters them. >> >> >> It's format_info we're talking about. What I mean is that you just set all >> these to 0 and let the format_info code ignore it. And then having a >> bespoke drm_format_check_afbc helper function or similar, which checks all >> the layout restrictions of afbc. >> >> I still maintain that bpp and tile_size are equavalent, and we really >> don't need both. Both are defacto a form of numerator/denumerator. If you >> don't like that you have to introduce "fake" tiles for afbc, then we can >> rename tile_size to numerator and tile_h/w to denumerator_h/w. Doesn't >> change one bit of the math. bpp simply hardcodes a denumerator of 8, and I >> don't see why we need that special case. Except if you love to write >> redundant self tests for all the math :-) >> >> So two options that I think are reasonable: >> - one common numerator/denumerator. I don't care how you call that >> bikeshed. > > > Sorry for being
Re: [RFC PATCH v2 1/3] drm/fourcc: Add 'bpp' field for formats with non-integer bytes-per-pixel
On Wed, Sep 12, 2018 at 04:27:04PM +0100, Liviu Dudau wrote: On Mon, Sep 10, 2018 at 09:53:25PM +0200, Daniel Vetter wrote: On Mon, Sep 10, 2018 at 09:50:03AM +0100, Brian Starkey wrote: > Hi, > > On Fri, Sep 07, 2018 at 09:28:44PM +0200, Daniel Vetter wrote: > > On Fri, Sep 07, 2018 at 01:45:36PM +0100, Brian Starkey wrote: > > > Hi Daniel, > > > > > > On Fri, Aug 31, 2018 at 10:17:30AM +0200, Daniel Vetter wrote: > > > > On Thu, Aug 23, 2018 at 04:23:41PM +0100, Brian Starkey wrote: > > > > > Some formats have a non-integer number of bytes per pixel, which can't > > > > > be handled with the existing 'cpp' field in drm_format_info. To handle > > > > > these formats, add a 'bpp' field, which is only used if cpp[0] == 0. > > > > > > > > > > This updates all the users of format->cpp in the core DRM code, > > > > > converting them to use a new function to get the bits-per-pixel for any > > > > > format. > > > > > > > > > > It's assumed that drivers will use the 'bpp' field when they add support > > > > > for pixel formats with non-integer bytes-per-pixel. > > > > > > > > > > Signed-off-by: Brian Starkey > > > > > > > > I assume you still require that stuff is eventually aligned to bytes? In > > > > that case, can we subsume this into the tile work Alex is doing? It's > > > > essentially just another special case of having storage-size units > > > > measured in bytes which span more than 1x1 pixel. And I kinda don't want a > > > > metric pile of special cases here in the format code, because that just > > > > means every driver handles a different subset, with different bugs. > > > > -Daniel > > > > > > Sorry for the delay, been struggling to free some cycles to think > > > about this. > > > > > > I'm not sure how to pull this in with the tiling stuff. In the AFBC > > > case then our AFBC superblocks are always nice round numbers (256 > > > pixels), and so it does end up being a multiple of bytes. > > > > > > However, AFBC supports different superblock sizes, so picking just one > > > doesn't really work out, and putting AFBC in the core format table > > > which reflects AFBC doesn't seem good. > > > > > > We could make something up (e.g. call these formats "tiled" with 2x4 > > > tiles, which guarantees a multiple of 8), but it would be an > > > arbitrarily-selected lie, which often seems to spell trouble. If we > > > did do that, would you re-define cpp as "bytes-per-tile"? Otherwise > > > we still need to add a new field anyway. > > > > > > What's the pile of special cases you're worried about? The helper I've > > > added here means that drivers which need to care can use one API and > > > not implement their own bugs. > > > > I'm confused ... the new bits-per-pixel stuff you're adding here is for > > yuv formats, not afbc. I'm just suggesting we have only 1 way of > > describing such formats that need more descriptive power than cpp, whether > > they have some kind of pixel-groups or small tiles. > > Well, not really. The three formats which have non-integer cpp are: > DRM_FORMAT_VUY101010, DRM_FORMAT_YUV420_8BIT and > DRM_FORMAT_YUV420_10BIT. These formats are only valid with non-linear > modifiers (no linear encoding is defined). Mali only supports them > with AFBC. > > The formats themselves have no notion of tiling or grouping - the > modifier adds that. I'm not aware of any non-AFBC uses of these > formats, so I don't want to "make up" a small-tile layout restriction > for them. Ah, I missed that. > > For very special stuff like afbc you need to validate in the driver > > anyway, too complicated. So I have no idea why you bring this up here? > > Sure, we can just let drivers provide their own format_info's for > these, if that's what you prefer. The core format checking code can > error out if it ever encounters them. It's format_info we're talking about. What I mean is that you just set all these to 0 and let the format_info code ignore it. And then having a bespoke drm_format_check_afbc helper function or similar, which checks all the layout restrictions of afbc. I still maintain that bpp and tile_size are equavalent, and we really don't need both. Both are defacto a form of numerator/denumerator. If you don't like that you have to introduce "fake" tiles for afbc, then we can rename tile_size to numerator and tile_h/w to denumerator_h/w. Doesn't change one bit of the math. bpp simply hardcodes a denumerator of 8, and I don't see why we need that special case. Except if you love to write redundant self tests for all the math :-) My $.02 worth of thoughts: I get the fact that Daniel doesn't like us to add 3 new variables into format_info (bpp, tile_w, tile_h) and that adding a "bits_per_unit" variable should be able to take care of linear (where unit = 1 pixel) and tiled (where unit = tile_w * tile_h pixels) formats. And I also see Daniel's option 2 below, where he says it is reasonable to check AFBC without using format_info. However, the problem we are trying to solve is 2 fold: we ar
Re: [RFC PATCH v2 1/3] drm/fourcc: Add 'bpp' field for formats with non-integer bytes-per-pixel
On Mon, Sep 10, 2018 at 09:53:25PM +0200, Daniel Vetter wrote: > On Mon, Sep 10, 2018 at 09:50:03AM +0100, Brian Starkey wrote: > > Hi, > > > > On Fri, Sep 07, 2018 at 09:28:44PM +0200, Daniel Vetter wrote: > > > On Fri, Sep 07, 2018 at 01:45:36PM +0100, Brian Starkey wrote: > > > > Hi Daniel, > > > > > > > > On Fri, Aug 31, 2018 at 10:17:30AM +0200, Daniel Vetter wrote: > > > > > On Thu, Aug 23, 2018 at 04:23:41PM +0100, Brian Starkey wrote: > > > > > > Some formats have a non-integer number of bytes per pixel, which > > > > > > can't > > > > > > be handled with the existing 'cpp' field in drm_format_info. To > > > > > > handle > > > > > > these formats, add a 'bpp' field, which is only used if cpp[0] == 0. > > > > > > > > > > > > This updates all the users of format->cpp in the core DRM code, > > > > > > converting them to use a new function to get the bits-per-pixel for > > > > > > any > > > > > > format. > > > > > > > > > > > > It's assumed that drivers will use the 'bpp' field when they add > > > > > > support > > > > > > for pixel formats with non-integer bytes-per-pixel. > > > > > > > > > > > > Signed-off-by: Brian Starkey > > > > > > > > > > I assume you still require that stuff is eventually aligned to bytes? > > > > > In > > > > > that case, can we subsume this into the tile work Alex is doing? It's > > > > > essentially just another special case of having storage-size units > > > > > measured in bytes which span more than 1x1 pixel. And I kinda don't > > > > > want a > > > > > metric pile of special cases here in the format code, because that > > > > > just > > > > > means every driver handles a different subset, with different bugs. > > > > > -Daniel > > > > > > > > Sorry for the delay, been struggling to free some cycles to think > > > > about this. > > > > > > > > I'm not sure how to pull this in with the tiling stuff. In the AFBC > > > > case then our AFBC superblocks are always nice round numbers (256 > > > > pixels), and so it does end up being a multiple of bytes. > > > > > > > > However, AFBC supports different superblock sizes, so picking just one > > > > doesn't really work out, and putting AFBC in the core format table > > > > which reflects AFBC doesn't seem good. > > > > > > > > We could make something up (e.g. call these formats "tiled" with 2x4 > > > > tiles, which guarantees a multiple of 8), but it would be an > > > > arbitrarily-selected lie, which often seems to spell trouble. If we > > > > did do that, would you re-define cpp as "bytes-per-tile"? Otherwise > > > > we still need to add a new field anyway. > > > > > > > > What's the pile of special cases you're worried about? The helper I've > > > > added here means that drivers which need to care can use one API and > > > > not implement their own bugs. > > > > > > I'm confused ... the new bits-per-pixel stuff you're adding here is for > > > yuv formats, not afbc. I'm just suggesting we have only 1 way of > > > describing such formats that need more descriptive power than cpp, whether > > > they have some kind of pixel-groups or small tiles. > > > > Well, not really. The three formats which have non-integer cpp are: > > DRM_FORMAT_VUY101010, DRM_FORMAT_YUV420_8BIT and > > DRM_FORMAT_YUV420_10BIT. These formats are only valid with non-linear > > modifiers (no linear encoding is defined). Mali only supports them > > with AFBC. > > > > The formats themselves have no notion of tiling or grouping - the > > modifier adds that. I'm not aware of any non-AFBC uses of these > > formats, so I don't want to "make up" a small-tile layout restriction > > for them. > > Ah, I missed that. > > > > For very special stuff like afbc you need to validate in the driver > > > anyway, too complicated. So I have no idea why you bring this up here? > > > > Sure, we can just let drivers provide their own format_info's for > > these, if that's what you prefer. The core format checking code can > > error out if it ever encounters them. > > It's format_info we're talking about. What I mean is that you just set all > these to 0 and let the format_info code ignore it. And then having a > bespoke drm_format_check_afbc helper function or similar, which checks all > the layout restrictions of afbc. > > I still maintain that bpp and tile_size are equavalent, and we really > don't need both. Both are defacto a form of numerator/denumerator. If you > don't like that you have to introduce "fake" tiles for afbc, then we can > rename tile_size to numerator and tile_h/w to denumerator_h/w. Doesn't > change one bit of the math. bpp simply hardcodes a denumerator of 8, and I > don't see why we need that special case. Except if you love to write > redundant self tests for all the math :-) My $.02 worth of thoughts: I get the fact that Daniel doesn't like us to add 3 new variables into format_info (bpp, tile_w, tile_h) and that adding a "bits_per_unit" variable should be able to take care of linear (where unit = 1 pixel) and tiled (where unit = ti
Re: [RFC PATCH v2 1/3] drm/fourcc: Add 'bpp' field for formats with non-integer bytes-per-pixel
On Mon, Sep 10, 2018 at 09:53:25PM +0200, Daniel Vetter wrote: On Mon, Sep 10, 2018 at 09:50:03AM +0100, Brian Starkey wrote: Hi, On Fri, Sep 07, 2018 at 09:28:44PM +0200, Daniel Vetter wrote: > On Fri, Sep 07, 2018 at 01:45:36PM +0100, Brian Starkey wrote: > > Hi Daniel, > > > > On Fri, Aug 31, 2018 at 10:17:30AM +0200, Daniel Vetter wrote: > > > On Thu, Aug 23, 2018 at 04:23:41PM +0100, Brian Starkey wrote: > > > > Some formats have a non-integer number of bytes per pixel, which can't > > > > be handled with the existing 'cpp' field in drm_format_info. To handle > > > > these formats, add a 'bpp' field, which is only used if cpp[0] == 0. > > > > > > > > This updates all the users of format->cpp in the core DRM code, > > > > converting them to use a new function to get the bits-per-pixel for any > > > > format. > > > > > > > > It's assumed that drivers will use the 'bpp' field when they add support > > > > for pixel formats with non-integer bytes-per-pixel. > > > > > > > > Signed-off-by: Brian Starkey > > > > > > I assume you still require that stuff is eventually aligned to bytes? In > > > that case, can we subsume this into the tile work Alex is doing? It's > > > essentially just another special case of having storage-size units > > > measured in bytes which span more than 1x1 pixel. And I kinda don't want a > > > metric pile of special cases here in the format code, because that just > > > means every driver handles a different subset, with different bugs. > > > -Daniel > > > > Sorry for the delay, been struggling to free some cycles to think > > about this. > > > > I'm not sure how to pull this in with the tiling stuff. In the AFBC > > case then our AFBC superblocks are always nice round numbers (256 > > pixels), and so it does end up being a multiple of bytes. > > > > However, AFBC supports different superblock sizes, so picking just one > > doesn't really work out, and putting AFBC in the core format table > > which reflects AFBC doesn't seem good. > > > > We could make something up (e.g. call these formats "tiled" with 2x4 > > tiles, which guarantees a multiple of 8), but it would be an > > arbitrarily-selected lie, which often seems to spell trouble. If we > > did do that, would you re-define cpp as "bytes-per-tile"? Otherwise > > we still need to add a new field anyway. > > > > What's the pile of special cases you're worried about? The helper I've > > added here means that drivers which need to care can use one API and > > not implement their own bugs. > > I'm confused ... the new bits-per-pixel stuff you're adding here is for > yuv formats, not afbc. I'm just suggesting we have only 1 way of > describing such formats that need more descriptive power than cpp, whether > they have some kind of pixel-groups or small tiles. Well, not really. The three formats which have non-integer cpp are: DRM_FORMAT_VUY101010, DRM_FORMAT_YUV420_8BIT and DRM_FORMAT_YUV420_10BIT. These formats are only valid with non-linear modifiers (no linear encoding is defined). Mali only supports them with AFBC. The formats themselves have no notion of tiling or grouping - the modifier adds that. I'm not aware of any non-AFBC uses of these formats, so I don't want to "make up" a small-tile layout restriction for them. Ah, I missed that. > For very special stuff like afbc you need to validate in the driver > anyway, too complicated. So I have no idea why you bring this up here? Sure, we can just let drivers provide their own format_info's for these, if that's what you prefer. The core format checking code can error out if it ever encounters them. It's format_info we're talking about. What I mean is that you just set all these to 0 and let the format_info code ignore it. And then having a bespoke drm_format_check_afbc helper function or similar, which checks all the layout restrictions of afbc. I still maintain that bpp and tile_size are equavalent, and we really don't need both. Both are defacto a form of numerator/denumerator. If you don't like that you have to introduce "fake" tiles for afbc, then we can rename tile_size to numerator and tile_h/w to denumerator_h/w. Doesn't change one bit of the math. bpp simply hardcodes a denumerator of 8, and I don't see why we need that special case. Except if you love to write redundant self tests for all the math :-) So two options that I think are reasonable: - one common numerator/denumerator. I don't care how you call that bikeshed. Sorry for being dense, but I'm still struggling to get my head around what you're suggesting. In particular "bpp simply hardcodes a denumerator of 8" didn't make any sense to me. Could you give concrete examples for how you think this would look for e.g. - DRM_FORMAT_VUY101010. 30-bits per pixel, no tiling. - DRM_FORMAT_Y0L2. 16-bits per pixel, 2x2 pixel tiles I think we need two things: - The size, in bits, of a tile - The width and height, in pixels, of a tile (currently implicitly 1x1) Do you disagree? Are you just saying that in
Re: [RFC PATCH v2 1/3] drm/fourcc: Add 'bpp' field for formats with non-integer bytes-per-pixel
On Mon, Sep 10, 2018 at 09:50:03AM +0100, Brian Starkey wrote: > Hi, > > On Fri, Sep 07, 2018 at 09:28:44PM +0200, Daniel Vetter wrote: > > On Fri, Sep 07, 2018 at 01:45:36PM +0100, Brian Starkey wrote: > > > Hi Daniel, > > > > > > On Fri, Aug 31, 2018 at 10:17:30AM +0200, Daniel Vetter wrote: > > > > On Thu, Aug 23, 2018 at 04:23:41PM +0100, Brian Starkey wrote: > > > > > Some formats have a non-integer number of bytes per pixel, which can't > > > > > be handled with the existing 'cpp' field in drm_format_info. To handle > > > > > these formats, add a 'bpp' field, which is only used if cpp[0] == 0. > > > > > > > > > > This updates all the users of format->cpp in the core DRM code, > > > > > converting them to use a new function to get the bits-per-pixel for > > > > > any > > > > > format. > > > > > > > > > > It's assumed that drivers will use the 'bpp' field when they add > > > > > support > > > > > for pixel formats with non-integer bytes-per-pixel. > > > > > > > > > > Signed-off-by: Brian Starkey > > > > > > > > I assume you still require that stuff is eventually aligned to bytes? In > > > > that case, can we subsume this into the tile work Alex is doing? It's > > > > essentially just another special case of having storage-size units > > > > measured in bytes which span more than 1x1 pixel. And I kinda don't > > > > want a > > > > metric pile of special cases here in the format code, because that just > > > > means every driver handles a different subset, with different bugs. > > > > -Daniel > > > > > > Sorry for the delay, been struggling to free some cycles to think > > > about this. > > > > > > I'm not sure how to pull this in with the tiling stuff. In the AFBC > > > case then our AFBC superblocks are always nice round numbers (256 > > > pixels), and so it does end up being a multiple of bytes. > > > > > > However, AFBC supports different superblock sizes, so picking just one > > > doesn't really work out, and putting AFBC in the core format table > > > which reflects AFBC doesn't seem good. > > > > > > We could make something up (e.g. call these formats "tiled" with 2x4 > > > tiles, which guarantees a multiple of 8), but it would be an > > > arbitrarily-selected lie, which often seems to spell trouble. If we > > > did do that, would you re-define cpp as "bytes-per-tile"? Otherwise > > > we still need to add a new field anyway. > > > > > > What's the pile of special cases you're worried about? The helper I've > > > added here means that drivers which need to care can use one API and > > > not implement their own bugs. > > > > I'm confused ... the new bits-per-pixel stuff you're adding here is for > > yuv formats, not afbc. I'm just suggesting we have only 1 way of > > describing such formats that need more descriptive power than cpp, whether > > they have some kind of pixel-groups or small tiles. > > Well, not really. The three formats which have non-integer cpp are: > DRM_FORMAT_VUY101010, DRM_FORMAT_YUV420_8BIT and > DRM_FORMAT_YUV420_10BIT. These formats are only valid with non-linear > modifiers (no linear encoding is defined). Mali only supports them > with AFBC. > > The formats themselves have no notion of tiling or grouping - the > modifier adds that. I'm not aware of any non-AFBC uses of these > formats, so I don't want to "make up" a small-tile layout restriction > for them. Ah, I missed that. > > For very special stuff like afbc you need to validate in the driver > > anyway, too complicated. So I have no idea why you bring this up here? > > Sure, we can just let drivers provide their own format_info's for > these, if that's what you prefer. The core format checking code can > error out if it ever encounters them. It's format_info we're talking about. What I mean is that you just set all these to 0 and let the format_info code ignore it. And then having a bespoke drm_format_check_afbc helper function or similar, which checks all the layout restrictions of afbc. I still maintain that bpp and tile_size are equavalent, and we really don't need both. Both are defacto a form of numerator/denumerator. If you don't like that you have to introduce "fake" tiles for afbc, then we can rename tile_size to numerator and tile_h/w to denumerator_h/w. Doesn't change one bit of the math. bpp simply hardcodes a denumerator of 8, and I don't see why we need that special case. Except if you love to write redundant self tests for all the math :-) So two options that I think are reasonable: - one common numerator/denumerator. I don't care how you call that bikeshed. - don't check afbc using format_info, have your own helper that does that using custom code. Cheers, Daniel > Cheers, > -Brian > > > -Daniel > > > > > > > > Cheers, > > > -Brian > > > > > > > > > > > > --- > > > > > drivers/gpu/drm/drm_fb_cma_helper.c | 6 +++- > > > > > drivers/gpu/drm/drm_fb_helper.c | 8 +++-- > > > > > drivers/gpu/drm/drm_fourcc.c | 50 > > > > > ++
Re: [RFC PATCH v2 1/3] drm/fourcc: Add 'bpp' field for formats with non-integer bytes-per-pixel
Hi Ayan, On Mon, Sep 10, 2018 at 03:11:34PM +0100, Ayan Halder wrote: On Fri, Aug 31, 2018 at 10:17:30AM +0200, Daniel Vetter wrote: On Thu, Aug 23, 2018 at 04:23:41PM +0100, Brian Starkey wrote: [snip] >unsigned int min_size; > + u8 bpp = drm_format_info_plane_bpp(fb->format, i); You might want to pass info here instead of fb->format because fb is NULL. ie drm_format_info_plane_bpp(info, i); Thanks, good catch. I have to admit I only compile-tested these. -Brian ___ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel
Re: [RFC PATCH v2 1/3] drm/fourcc: Add 'bpp' field for formats with non-integer bytes-per-pixel
On Fri, Aug 31, 2018 at 10:17:30AM +0200, Daniel Vetter wrote:
> On Thu, Aug 23, 2018 at 04:23:41PM +0100, Brian Starkey wrote:
> > Some formats have a non-integer number of bytes per pixel, which can't
> > be handled with the existing 'cpp' field in drm_format_info. To handle
> > these formats, add a 'bpp' field, which is only used if cpp[0] == 0.
> >
> > This updates all the users of format->cpp in the core DRM code,
> > converting them to use a new function to get the bits-per-pixel for any
> > format.
> >
> > It's assumed that drivers will use the 'bpp' field when they add support
> > for pixel formats with non-integer bytes-per-pixel.
> >
> > Signed-off-by: Brian Starkey
>
> I assume you still require that stuff is eventually aligned to bytes? In
> that case, can we subsume this into the tile work Alex is doing? It's
> essentially just another special case of having storage-size units
> measured in bytes which span more than 1x1 pixel. And I kinda don't want a
> metric pile of special cases here in the format code, because that just
> means every driver handles a different subset, with different bugs.
> -Daniel
>
> > ---
> > drivers/gpu/drm/drm_fb_cma_helper.c | 6 +++-
> > drivers/gpu/drm/drm_fb_helper.c | 8 +++--
> > drivers/gpu/drm/drm_fourcc.c | 50
> >
> > drivers/gpu/drm/drm_framebuffer.c| 8 ++---
> > drivers/gpu/drm/drm_gem_framebuffer_helper.c | 3 +-
> > include/drm/drm_fourcc.h | 4 +++
> > 6 files changed, 70 insertions(+), 9 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/drm_fb_cma_helper.c
> > b/drivers/gpu/drm/drm_fb_cma_helper.c
> > index 186d00adfb5f..e279d70d3e60 100644
> > --- a/drivers/gpu/drm/drm_fb_cma_helper.c
> > +++ b/drivers/gpu/drm/drm_fb_cma_helper.c
> > @@ -118,13 +118,17 @@ dma_addr_t drm_fb_cma_get_gem_addr(struct
> > drm_framebuffer *fb,
> > {
> > struct drm_gem_cma_object *obj;
> > dma_addr_t paddr;
> > + u8 bpp = drm_format_info_plane_bpp(fb->format, plane);
> > +
> > + /* This can't work for non-integer bytes-per-pixel */
> > + WARN_ON(bpp % 8);
> >
> > obj = drm_fb_cma_get_gem_obj(fb, plane);
> > if (!obj)
> > return 0;
> >
> > paddr = obj->paddr + fb->offsets[plane];
> > - paddr += fb->format->cpp[plane] * (state->src_x >> 16);
> > + paddr += (bpp / 8) * (state->src_x >> 16);
> > paddr += fb->pitches[plane] * (state->src_y >> 16);
> >
> > return paddr;
> > diff --git a/drivers/gpu/drm/drm_fb_helper.c
> > b/drivers/gpu/drm/drm_fb_helper.c
> > index 0646b108030b..ab369f250af4 100644
> > --- a/drivers/gpu/drm/drm_fb_helper.c
> > +++ b/drivers/gpu/drm/drm_fb_helper.c
> > @@ -1572,6 +1572,7 @@ int drm_fb_helper_check_var(struct fb_var_screeninfo
> > *var,
> > struct drm_fb_helper *fb_helper = info->par;
> > struct drm_framebuffer *fb = fb_helper->fb;
> > int depth;
> > + u8 bpp = drm_format_info_plane_bpp(fb->format, 0);
> >
> > if (var->pixclock != 0 || in_dbg_master())
> > return -EINVAL;
> > @@ -1580,14 +1581,14 @@ int drm_fb_helper_check_var(struct
> > fb_var_screeninfo *var,
> > * Changes struct fb_var_screeninfo are currently not pushed back
> > * to KMS, hence fail if different settings are requested.
> > */
> > - if (var->bits_per_pixel != fb->format->cpp[0] * 8 ||
> > + if (var->bits_per_pixel != bpp ||
> > var->xres > fb->width || var->yres > fb->height ||
> > var->xres_virtual > fb->width || var->yres_virtual > fb->height) {
> > DRM_DEBUG("fb requested width/height/bpp can't fit in current
> > fb "
> > "request %dx%d-%d (virtual %dx%d) > %dx%d-%d\n",
> > var->xres, var->yres, var->bits_per_pixel,
> > var->xres_virtual, var->yres_virtual,
> > - fb->width, fb->height, fb->format->cpp[0] * 8);
> > + fb->width, fb->height, bpp);
> > return -EINVAL;
> > }
> >
> > @@ -1949,11 +1950,12 @@ void drm_fb_helper_fill_var(struct fb_info *info,
> > struct drm_fb_helper *fb_helpe
> > uint32_t fb_width, uint32_t fb_height)
> > {
> > struct drm_framebuffer *fb = fb_helper->fb;
> > + u8 bpp = drm_format_info_plane_bpp(fb->format, 0);
> >
> > info->pseudo_palette = fb_helper->pseudo_palette;
> > info->var.xres_virtual = fb->width;
> > info->var.yres_virtual = fb->height;
> > - info->var.bits_per_pixel = fb->format->cpp[0] * 8;
> > + info->var.bits_per_pixel = bpp;
> > info->var.accel_flags = FB_ACCELF_TEXT;
> > info->var.xoffset = 0;
> > info->var.yoffset = 0;
> > diff --git a/drivers/gpu/drm/drm_fourcc.c b/drivers/gpu/drm/drm_fourcc.c
> > index 3b42c25bd58d..bb28919c32f3 100644
> > --- a/drivers/gpu/drm/drm_fourcc.c
> > +++ b/drivers/gpu/drm/drm_fourcc.c
> > @@ -272,10 +272,60 @@ int drm_format_plane_cpp(uint32_t format, int plane)
> >
Re: [RFC PATCH v2 1/3] drm/fourcc: Add 'bpp' field for formats with non-integer bytes-per-pixel
Hi,
On Fri, Sep 07, 2018 at 09:28:44PM +0200, Daniel Vetter wrote:
On Fri, Sep 07, 2018 at 01:45:36PM +0100, Brian Starkey wrote:
Hi Daniel,
On Fri, Aug 31, 2018 at 10:17:30AM +0200, Daniel Vetter wrote:
> On Thu, Aug 23, 2018 at 04:23:41PM +0100, Brian Starkey wrote:
> > Some formats have a non-integer number of bytes per pixel, which can't
> > be handled with the existing 'cpp' field in drm_format_info. To handle
> > these formats, add a 'bpp' field, which is only used if cpp[0] == 0.
> >
> > This updates all the users of format->cpp in the core DRM code,
> > converting them to use a new function to get the bits-per-pixel for any
> > format.
> >
> > It's assumed that drivers will use the 'bpp' field when they add support
> > for pixel formats with non-integer bytes-per-pixel.
> >
> > Signed-off-by: Brian Starkey
>
> I assume you still require that stuff is eventually aligned to bytes? In
> that case, can we subsume this into the tile work Alex is doing? It's
> essentially just another special case of having storage-size units
> measured in bytes which span more than 1x1 pixel. And I kinda don't want a
> metric pile of special cases here in the format code, because that just
> means every driver handles a different subset, with different bugs.
> -Daniel
Sorry for the delay, been struggling to free some cycles to think
about this.
I'm not sure how to pull this in with the tiling stuff. In the AFBC
case then our AFBC superblocks are always nice round numbers (256
pixels), and so it does end up being a multiple of bytes.
However, AFBC supports different superblock sizes, so picking just one
doesn't really work out, and putting AFBC in the core format table
which reflects AFBC doesn't seem good.
We could make something up (e.g. call these formats "tiled" with 2x4
tiles, which guarantees a multiple of 8), but it would be an
arbitrarily-selected lie, which often seems to spell trouble. If we
did do that, would you re-define cpp as "bytes-per-tile"? Otherwise
we still need to add a new field anyway.
What's the pile of special cases you're worried about? The helper I've
added here means that drivers which need to care can use one API and
not implement their own bugs.
I'm confused ... the new bits-per-pixel stuff you're adding here is for
yuv formats, not afbc. I'm just suggesting we have only 1 way of
describing such formats that need more descriptive power than cpp, whether
they have some kind of pixel-groups or small tiles.
Well, not really. The three formats which have non-integer cpp are:
DRM_FORMAT_VUY101010, DRM_FORMAT_YUV420_8BIT and
DRM_FORMAT_YUV420_10BIT. These formats are only valid with non-linear
modifiers (no linear encoding is defined). Mali only supports them
with AFBC.
The formats themselves have no notion of tiling or grouping - the
modifier adds that. I'm not aware of any non-AFBC uses of these
formats, so I don't want to "make up" a small-tile layout restriction
for them.
For very special stuff like afbc you need to validate in the driver
anyway, too complicated. So I have no idea why you bring this up here?
Sure, we can just let drivers provide their own format_info's for
these, if that's what you prefer. The core format checking code can
error out if it ever encounters them.
Cheers,
-Brian
-Daniel
Cheers,
-Brian
>
> > ---
> > drivers/gpu/drm/drm_fb_cma_helper.c | 6 +++-
> > drivers/gpu/drm/drm_fb_helper.c | 8 +++--
> > drivers/gpu/drm/drm_fourcc.c | 50
> > drivers/gpu/drm/drm_framebuffer.c| 8 ++---
> > drivers/gpu/drm/drm_gem_framebuffer_helper.c | 3 +-
> > include/drm/drm_fourcc.h | 4 +++
> > 6 files changed, 70 insertions(+), 9 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/drm_fb_cma_helper.c
b/drivers/gpu/drm/drm_fb_cma_helper.c
> > index 186d00adfb5f..e279d70d3e60 100644
> > --- a/drivers/gpu/drm/drm_fb_cma_helper.c
> > +++ b/drivers/gpu/drm/drm_fb_cma_helper.c
> > @@ -118,13 +118,17 @@ dma_addr_t drm_fb_cma_get_gem_addr(struct
drm_framebuffer *fb,
> > {
> > struct drm_gem_cma_object *obj;
> > dma_addr_t paddr;
> > + u8 bpp = drm_format_info_plane_bpp(fb->format, plane);
> > +
> > + /* This can't work for non-integer bytes-per-pixel */
> > + WARN_ON(bpp % 8);
> >
> > obj = drm_fb_cma_get_gem_obj(fb, plane);
> > if (!obj)
> > return 0;
> >
> > paddr = obj->paddr + fb->offsets[plane];
> > - paddr += fb->format->cpp[plane] * (state->src_x >> 16);
> > + paddr += (bpp / 8) * (state->src_x >> 16);
> > paddr += fb->pitches[plane] * (state->src_y >> 16);
> >
> > return paddr;
> > diff --git a/drivers/gpu/drm/drm_fb_helper.c
b/drivers/gpu/drm/drm_fb_helper.c
> > index 0646b108030b..ab369f250af4 100644
> > --- a/drivers/gpu/drm/drm_fb_helper.c
> > +++ b/drivers/gpu/drm/drm_fb_helper.c
> > @@ -1572,6 +1572,7 @@ int drm_fb_helper_check_var(struct fb_var_screeninfo
*var,
> >
Re: [RFC PATCH v2 1/3] drm/fourcc: Add 'bpp' field for formats with non-integer bytes-per-pixel
On Fri, Sep 07, 2018 at 01:45:36PM +0100, Brian Starkey wrote:
> Hi Daniel,
>
> On Fri, Aug 31, 2018 at 10:17:30AM +0200, Daniel Vetter wrote:
> > On Thu, Aug 23, 2018 at 04:23:41PM +0100, Brian Starkey wrote:
> > > Some formats have a non-integer number of bytes per pixel, which can't
> > > be handled with the existing 'cpp' field in drm_format_info. To handle
> > > these formats, add a 'bpp' field, which is only used if cpp[0] == 0.
> > >
> > > This updates all the users of format->cpp in the core DRM code,
> > > converting them to use a new function to get the bits-per-pixel for any
> > > format.
> > >
> > > It's assumed that drivers will use the 'bpp' field when they add support
> > > for pixel formats with non-integer bytes-per-pixel.
> > >
> > > Signed-off-by: Brian Starkey
> >
> > I assume you still require that stuff is eventually aligned to bytes? In
> > that case, can we subsume this into the tile work Alex is doing? It's
> > essentially just another special case of having storage-size units
> > measured in bytes which span more than 1x1 pixel. And I kinda don't want a
> > metric pile of special cases here in the format code, because that just
> > means every driver handles a different subset, with different bugs.
> > -Daniel
>
> Sorry for the delay, been struggling to free some cycles to think
> about this.
>
> I'm not sure how to pull this in with the tiling stuff. In the AFBC
> case then our AFBC superblocks are always nice round numbers (256
> pixels), and so it does end up being a multiple of bytes.
>
> However, AFBC supports different superblock sizes, so picking just one
> doesn't really work out, and putting AFBC in the core format table
> which reflects AFBC doesn't seem good.
>
> We could make something up (e.g. call these formats "tiled" with 2x4
> tiles, which guarantees a multiple of 8), but it would be an
> arbitrarily-selected lie, which often seems to spell trouble. If we
> did do that, would you re-define cpp as "bytes-per-tile"? Otherwise
> we still need to add a new field anyway.
>
> What's the pile of special cases you're worried about? The helper I've
> added here means that drivers which need to care can use one API and
> not implement their own bugs.
I'm confused ... the new bits-per-pixel stuff you're adding here is for
yuv formats, not afbc. I'm just suggesting we have only 1 way of
describing such formats that need more descriptive power than cpp, whether
they have some kind of pixel-groups or small tiles.
For very special stuff like afbc you need to validate in the driver
anyway, too complicated. So I have no idea why you bring this up here?
-Daniel
>
> Cheers,
> -Brian
>
> >
> > > ---
> > > drivers/gpu/drm/drm_fb_cma_helper.c | 6 +++-
> > > drivers/gpu/drm/drm_fb_helper.c | 8 +++--
> > > drivers/gpu/drm/drm_fourcc.c | 50
> > >
> > > drivers/gpu/drm/drm_framebuffer.c| 8 ++---
> > > drivers/gpu/drm/drm_gem_framebuffer_helper.c | 3 +-
> > > include/drm/drm_fourcc.h | 4 +++
> > > 6 files changed, 70 insertions(+), 9 deletions(-)
> > >
> > > diff --git a/drivers/gpu/drm/drm_fb_cma_helper.c
> > > b/drivers/gpu/drm/drm_fb_cma_helper.c
> > > index 186d00adfb5f..e279d70d3e60 100644
> > > --- a/drivers/gpu/drm/drm_fb_cma_helper.c
> > > +++ b/drivers/gpu/drm/drm_fb_cma_helper.c
> > > @@ -118,13 +118,17 @@ dma_addr_t drm_fb_cma_get_gem_addr(struct
> > > drm_framebuffer *fb,
> > > {
> > > struct drm_gem_cma_object *obj;
> > > dma_addr_t paddr;
> > > + u8 bpp = drm_format_info_plane_bpp(fb->format, plane);
> > > +
> > > + /* This can't work for non-integer bytes-per-pixel */
> > > + WARN_ON(bpp % 8);
> > >
> > > obj = drm_fb_cma_get_gem_obj(fb, plane);
> > > if (!obj)
> > > return 0;
> > >
> > > paddr = obj->paddr + fb->offsets[plane];
> > > - paddr += fb->format->cpp[plane] * (state->src_x >> 16);
> > > + paddr += (bpp / 8) * (state->src_x >> 16);
> > > paddr += fb->pitches[plane] * (state->src_y >> 16);
> > >
> > > return paddr;
> > > diff --git a/drivers/gpu/drm/drm_fb_helper.c
> > > b/drivers/gpu/drm/drm_fb_helper.c
> > > index 0646b108030b..ab369f250af4 100644
> > > --- a/drivers/gpu/drm/drm_fb_helper.c
> > > +++ b/drivers/gpu/drm/drm_fb_helper.c
> > > @@ -1572,6 +1572,7 @@ int drm_fb_helper_check_var(struct
> > > fb_var_screeninfo *var,
> > > struct drm_fb_helper *fb_helper = info->par;
> > > struct drm_framebuffer *fb = fb_helper->fb;
> > > int depth;
> > > + u8 bpp = drm_format_info_plane_bpp(fb->format, 0);
> > >
> > > if (var->pixclock != 0 || in_dbg_master())
> > > return -EINVAL;
> > > @@ -1580,14 +1581,14 @@ int drm_fb_helper_check_var(struct
> > > fb_var_screeninfo *var,
> > >* Changes struct fb_var_screeninfo are currently not pushed back
> > >* to KMS, hence fail if different settings are requested.
> > >*/
> > > - if (var->bits_per_pixel != fb->format->cpp[0] * 8 ||
> > > + i
Re: [RFC PATCH v2 1/3] drm/fourcc: Add 'bpp' field for formats with non-integer bytes-per-pixel
Hi Daniel,
On Fri, Aug 31, 2018 at 10:17:30AM +0200, Daniel Vetter wrote:
On Thu, Aug 23, 2018 at 04:23:41PM +0100, Brian Starkey wrote:
Some formats have a non-integer number of bytes per pixel, which can't
be handled with the existing 'cpp' field in drm_format_info. To handle
these formats, add a 'bpp' field, which is only used if cpp[0] == 0.
This updates all the users of format->cpp in the core DRM code,
converting them to use a new function to get the bits-per-pixel for any
format.
It's assumed that drivers will use the 'bpp' field when they add support
for pixel formats with non-integer bytes-per-pixel.
Signed-off-by: Brian Starkey
I assume you still require that stuff is eventually aligned to bytes? In
that case, can we subsume this into the tile work Alex is doing? It's
essentially just another special case of having storage-size units
measured in bytes which span more than 1x1 pixel. And I kinda don't want a
metric pile of special cases here in the format code, because that just
means every driver handles a different subset, with different bugs.
-Daniel
Sorry for the delay, been struggling to free some cycles to think
about this.
I'm not sure how to pull this in with the tiling stuff. In the AFBC
case then our AFBC superblocks are always nice round numbers (256
pixels), and so it does end up being a multiple of bytes.
However, AFBC supports different superblock sizes, so picking just one
doesn't really work out, and putting AFBC in the core format table
which reflects AFBC doesn't seem good.
We could make something up (e.g. call these formats "tiled" with 2x4
tiles, which guarantees a multiple of 8), but it would be an
arbitrarily-selected lie, which often seems to spell trouble. If we
did do that, would you re-define cpp as "bytes-per-tile"? Otherwise
we still need to add a new field anyway.
What's the pile of special cases you're worried about? The helper I've
added here means that drivers which need to care can use one API and
not implement their own bugs.
Cheers,
-Brian
---
drivers/gpu/drm/drm_fb_cma_helper.c | 6 +++-
drivers/gpu/drm/drm_fb_helper.c | 8 +++--
drivers/gpu/drm/drm_fourcc.c | 50
drivers/gpu/drm/drm_framebuffer.c| 8 ++---
drivers/gpu/drm/drm_gem_framebuffer_helper.c | 3 +-
include/drm/drm_fourcc.h | 4 +++
6 files changed, 70 insertions(+), 9 deletions(-)
diff --git a/drivers/gpu/drm/drm_fb_cma_helper.c
b/drivers/gpu/drm/drm_fb_cma_helper.c
index 186d00adfb5f..e279d70d3e60 100644
--- a/drivers/gpu/drm/drm_fb_cma_helper.c
+++ b/drivers/gpu/drm/drm_fb_cma_helper.c
@@ -118,13 +118,17 @@ dma_addr_t drm_fb_cma_get_gem_addr(struct drm_framebuffer
*fb,
{
struct drm_gem_cma_object *obj;
dma_addr_t paddr;
+ u8 bpp = drm_format_info_plane_bpp(fb->format, plane);
+
+ /* This can't work for non-integer bytes-per-pixel */
+ WARN_ON(bpp % 8);
obj = drm_fb_cma_get_gem_obj(fb, plane);
if (!obj)
return 0;
paddr = obj->paddr + fb->offsets[plane];
- paddr += fb->format->cpp[plane] * (state->src_x >> 16);
+ paddr += (bpp / 8) * (state->src_x >> 16);
paddr += fb->pitches[plane] * (state->src_y >> 16);
return paddr;
diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
index 0646b108030b..ab369f250af4 100644
--- a/drivers/gpu/drm/drm_fb_helper.c
+++ b/drivers/gpu/drm/drm_fb_helper.c
@@ -1572,6 +1572,7 @@ int drm_fb_helper_check_var(struct fb_var_screeninfo *var,
struct drm_fb_helper *fb_helper = info->par;
struct drm_framebuffer *fb = fb_helper->fb;
int depth;
+ u8 bpp = drm_format_info_plane_bpp(fb->format, 0);
if (var->pixclock != 0 || in_dbg_master())
return -EINVAL;
@@ -1580,14 +1581,14 @@ int drm_fb_helper_check_var(struct fb_var_screeninfo
*var,
* Changes struct fb_var_screeninfo are currently not pushed back
* to KMS, hence fail if different settings are requested.
*/
- if (var->bits_per_pixel != fb->format->cpp[0] * 8 ||
+ if (var->bits_per_pixel != bpp ||
var->xres > fb->width || var->yres > fb->height ||
var->xres_virtual > fb->width || var->yres_virtual > fb->height) {
DRM_DEBUG("fb requested width/height/bpp can't fit in current fb
"
"request %dx%d-%d (virtual %dx%d) > %dx%d-%d\n",
var->xres, var->yres, var->bits_per_pixel,
var->xres_virtual, var->yres_virtual,
- fb->width, fb->height, fb->format->cpp[0] * 8);
+ fb->width, fb->height, bpp);
return -EINVAL;
}
@@ -1949,11 +1950,12 @@ void drm_fb_helper_fill_var(struct fb_info *info,
struct drm_fb_helper *fb_helpe
uint32_t fb_width, uint32_t fb_height)
{
struct drm
Re: [RFC PATCH v2 1/3] drm/fourcc: Add 'bpp' field for formats with non-integer bytes-per-pixel
On Thu, Aug 23, 2018 at 04:23:41PM +0100, Brian Starkey wrote:
> Some formats have a non-integer number of bytes per pixel, which can't
> be handled with the existing 'cpp' field in drm_format_info. To handle
> these formats, add a 'bpp' field, which is only used if cpp[0] == 0.
>
> This updates all the users of format->cpp in the core DRM code,
> converting them to use a new function to get the bits-per-pixel for any
> format.
>
> It's assumed that drivers will use the 'bpp' field when they add support
> for pixel formats with non-integer bytes-per-pixel.
>
> Signed-off-by: Brian Starkey
I assume you still require that stuff is eventually aligned to bytes? In
that case, can we subsume this into the tile work Alex is doing? It's
essentially just another special case of having storage-size units
measured in bytes which span more than 1x1 pixel. And I kinda don't want a
metric pile of special cases here in the format code, because that just
means every driver handles a different subset, with different bugs.
-Daniel
> ---
> drivers/gpu/drm/drm_fb_cma_helper.c | 6 +++-
> drivers/gpu/drm/drm_fb_helper.c | 8 +++--
> drivers/gpu/drm/drm_fourcc.c | 50
>
> drivers/gpu/drm/drm_framebuffer.c| 8 ++---
> drivers/gpu/drm/drm_gem_framebuffer_helper.c | 3 +-
> include/drm/drm_fourcc.h | 4 +++
> 6 files changed, 70 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/gpu/drm/drm_fb_cma_helper.c
> b/drivers/gpu/drm/drm_fb_cma_helper.c
> index 186d00adfb5f..e279d70d3e60 100644
> --- a/drivers/gpu/drm/drm_fb_cma_helper.c
> +++ b/drivers/gpu/drm/drm_fb_cma_helper.c
> @@ -118,13 +118,17 @@ dma_addr_t drm_fb_cma_get_gem_addr(struct
> drm_framebuffer *fb,
> {
> struct drm_gem_cma_object *obj;
> dma_addr_t paddr;
> + u8 bpp = drm_format_info_plane_bpp(fb->format, plane);
> +
> + /* This can't work for non-integer bytes-per-pixel */
> + WARN_ON(bpp % 8);
>
> obj = drm_fb_cma_get_gem_obj(fb, plane);
> if (!obj)
> return 0;
>
> paddr = obj->paddr + fb->offsets[plane];
> - paddr += fb->format->cpp[plane] * (state->src_x >> 16);
> + paddr += (bpp / 8) * (state->src_x >> 16);
> paddr += fb->pitches[plane] * (state->src_y >> 16);
>
> return paddr;
> diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
> index 0646b108030b..ab369f250af4 100644
> --- a/drivers/gpu/drm/drm_fb_helper.c
> +++ b/drivers/gpu/drm/drm_fb_helper.c
> @@ -1572,6 +1572,7 @@ int drm_fb_helper_check_var(struct fb_var_screeninfo
> *var,
> struct drm_fb_helper *fb_helper = info->par;
> struct drm_framebuffer *fb = fb_helper->fb;
> int depth;
> + u8 bpp = drm_format_info_plane_bpp(fb->format, 0);
>
> if (var->pixclock != 0 || in_dbg_master())
> return -EINVAL;
> @@ -1580,14 +1581,14 @@ int drm_fb_helper_check_var(struct fb_var_screeninfo
> *var,
>* Changes struct fb_var_screeninfo are currently not pushed back
>* to KMS, hence fail if different settings are requested.
>*/
> - if (var->bits_per_pixel != fb->format->cpp[0] * 8 ||
> + if (var->bits_per_pixel != bpp ||
> var->xres > fb->width || var->yres > fb->height ||
> var->xres_virtual > fb->width || var->yres_virtual > fb->height) {
> DRM_DEBUG("fb requested width/height/bpp can't fit in current
> fb "
> "request %dx%d-%d (virtual %dx%d) > %dx%d-%d\n",
> var->xres, var->yres, var->bits_per_pixel,
> var->xres_virtual, var->yres_virtual,
> - fb->width, fb->height, fb->format->cpp[0] * 8);
> + fb->width, fb->height, bpp);
> return -EINVAL;
> }
>
> @@ -1949,11 +1950,12 @@ void drm_fb_helper_fill_var(struct fb_info *info,
> struct drm_fb_helper *fb_helpe
> uint32_t fb_width, uint32_t fb_height)
> {
> struct drm_framebuffer *fb = fb_helper->fb;
> + u8 bpp = drm_format_info_plane_bpp(fb->format, 0);
>
> info->pseudo_palette = fb_helper->pseudo_palette;
> info->var.xres_virtual = fb->width;
> info->var.yres_virtual = fb->height;
> - info->var.bits_per_pixel = fb->format->cpp[0] * 8;
> + info->var.bits_per_pixel = bpp;
> info->var.accel_flags = FB_ACCELF_TEXT;
> info->var.xoffset = 0;
> info->var.yoffset = 0;
> diff --git a/drivers/gpu/drm/drm_fourcc.c b/drivers/gpu/drm/drm_fourcc.c
> index 3b42c25bd58d..bb28919c32f3 100644
> --- a/drivers/gpu/drm/drm_fourcc.c
> +++ b/drivers/gpu/drm/drm_fourcc.c
> @@ -272,10 +272,60 @@ int drm_format_plane_cpp(uint32_t format, int plane)
> if (!info || plane >= info->num_planes)
> return 0;
>
> + /*
> + * Not valid for formats with non-integer cpp,
> + * use drm_format{_info}_plane_bpp instead
> +
[RFC PATCH v2 1/3] drm/fourcc: Add 'bpp' field for formats with non-integer bytes-per-pixel
Some formats have a non-integer number of bytes per pixel, which can't
be handled with the existing 'cpp' field in drm_format_info. To handle
these formats, add a 'bpp' field, which is only used if cpp[0] == 0.
This updates all the users of format->cpp in the core DRM code,
converting them to use a new function to get the bits-per-pixel for any
format.
It's assumed that drivers will use the 'bpp' field when they add support
for pixel formats with non-integer bytes-per-pixel.
Signed-off-by: Brian Starkey
---
drivers/gpu/drm/drm_fb_cma_helper.c | 6 +++-
drivers/gpu/drm/drm_fb_helper.c | 8 +++--
drivers/gpu/drm/drm_fourcc.c | 50
drivers/gpu/drm/drm_framebuffer.c| 8 ++---
drivers/gpu/drm/drm_gem_framebuffer_helper.c | 3 +-
include/drm/drm_fourcc.h | 4 +++
6 files changed, 70 insertions(+), 9 deletions(-)
diff --git a/drivers/gpu/drm/drm_fb_cma_helper.c
b/drivers/gpu/drm/drm_fb_cma_helper.c
index 186d00adfb5f..e279d70d3e60 100644
--- a/drivers/gpu/drm/drm_fb_cma_helper.c
+++ b/drivers/gpu/drm/drm_fb_cma_helper.c
@@ -118,13 +118,17 @@ dma_addr_t drm_fb_cma_get_gem_addr(struct drm_framebuffer
*fb,
{
struct drm_gem_cma_object *obj;
dma_addr_t paddr;
+ u8 bpp = drm_format_info_plane_bpp(fb->format, plane);
+
+ /* This can't work for non-integer bytes-per-pixel */
+ WARN_ON(bpp % 8);
obj = drm_fb_cma_get_gem_obj(fb, plane);
if (!obj)
return 0;
paddr = obj->paddr + fb->offsets[plane];
- paddr += fb->format->cpp[plane] * (state->src_x >> 16);
+ paddr += (bpp / 8) * (state->src_x >> 16);
paddr += fb->pitches[plane] * (state->src_y >> 16);
return paddr;
diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
index 0646b108030b..ab369f250af4 100644
--- a/drivers/gpu/drm/drm_fb_helper.c
+++ b/drivers/gpu/drm/drm_fb_helper.c
@@ -1572,6 +1572,7 @@ int drm_fb_helper_check_var(struct fb_var_screeninfo *var,
struct drm_fb_helper *fb_helper = info->par;
struct drm_framebuffer *fb = fb_helper->fb;
int depth;
+ u8 bpp = drm_format_info_plane_bpp(fb->format, 0);
if (var->pixclock != 0 || in_dbg_master())
return -EINVAL;
@@ -1580,14 +1581,14 @@ int drm_fb_helper_check_var(struct fb_var_screeninfo
*var,
* Changes struct fb_var_screeninfo are currently not pushed back
* to KMS, hence fail if different settings are requested.
*/
- if (var->bits_per_pixel != fb->format->cpp[0] * 8 ||
+ if (var->bits_per_pixel != bpp ||
var->xres > fb->width || var->yres > fb->height ||
var->xres_virtual > fb->width || var->yres_virtual > fb->height) {
DRM_DEBUG("fb requested width/height/bpp can't fit in current
fb "
"request %dx%d-%d (virtual %dx%d) > %dx%d-%d\n",
var->xres, var->yres, var->bits_per_pixel,
var->xres_virtual, var->yres_virtual,
- fb->width, fb->height, fb->format->cpp[0] * 8);
+ fb->width, fb->height, bpp);
return -EINVAL;
}
@@ -1949,11 +1950,12 @@ void drm_fb_helper_fill_var(struct fb_info *info,
struct drm_fb_helper *fb_helpe
uint32_t fb_width, uint32_t fb_height)
{
struct drm_framebuffer *fb = fb_helper->fb;
+ u8 bpp = drm_format_info_plane_bpp(fb->format, 0);
info->pseudo_palette = fb_helper->pseudo_palette;
info->var.xres_virtual = fb->width;
info->var.yres_virtual = fb->height;
- info->var.bits_per_pixel = fb->format->cpp[0] * 8;
+ info->var.bits_per_pixel = bpp;
info->var.accel_flags = FB_ACCELF_TEXT;
info->var.xoffset = 0;
info->var.yoffset = 0;
diff --git a/drivers/gpu/drm/drm_fourcc.c b/drivers/gpu/drm/drm_fourcc.c
index 3b42c25bd58d..bb28919c32f3 100644
--- a/drivers/gpu/drm/drm_fourcc.c
+++ b/drivers/gpu/drm/drm_fourcc.c
@@ -272,10 +272,60 @@ int drm_format_plane_cpp(uint32_t format, int plane)
if (!info || plane >= info->num_planes)
return 0;
+ /*
+* Not valid for formats with non-integer cpp,
+* use drm_format{_info}_plane_bpp instead
+*/
+ WARN_ON(!info->cpp[0]);
+
return info->cpp[plane];
}
EXPORT_SYMBOL(drm_format_plane_cpp);
+/**
+ * drm_format_plane_bpp - determine the bits per pixel value
+ * @format: pixel format (DRM_FORMAT_*)
+ * @plane: plane index
+ *
+ * Returns:
+ * The bits per pixel value for the specified plane.
+ */
+int drm_format_plane_bpp(uint32_t format, int plane)
+{
+ const struct drm_format_info *info;
+
+ info = drm_format_info(format);
+ if (!info)
+ return 0;
+
+ return drm_format_info_plane_bpp(info, plane);
+}
+EXPORT_SYMBOL(drm_format_plane_bpp);
+
+
