<feed xmlns='http://www.w3.org/2005/Atom'>
<title>BMC/Intel-BMC/linux.git/drivers/gpu/drm/drm_fourcc.c, branch dev-5.2</title>
<subtitle>Intel OpenBMC Linux kernel source tree (mirror)</subtitle>
<id>https://git.radix-linux.su/BMC/Intel-BMC/linux.git/atom?h=dev-5.2</id>
<link rel='self' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/atom?h=dev-5.2'/>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/'/>
<updated>2019-03-21T08:49:04+00:00</updated>
<entry>
<title>drm/fourcc: Fix conflicting Y41x definitions</title>
<updated>2019-03-21T08:49:04+00:00</updated>
<author>
<name>Maarten Lankhorst</name>
<email>maarten.lankhorst@linux.intel.com</email>
</author>
<published>2019-03-19T12:17:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=ff01e6971ecd9ba6a9c0538c46d713f38a751f11'/>
<id>urn:sha1:ff01e6971ecd9ba6a9c0538c46d713f38a751f11</id>
<content type='text'>
There has unfortunately been a conflict with the following 3 commits:

commit e9961ab95af81b8d29054361cd5f0c575102cf87
Author: Ayan Kumar Halder &lt;ayan.halder@arm.com&gt;
Date:   Fri Nov 9 17:21:12 2018 +0000
    drm: Added a new format DRM_FORMAT_XVYU2101010

commit 7ba0fee247ee7a36b3bfbed68f6988d980aa3aa3
Author: Brian Starkey &lt;brian.starkey@arm.com&gt;
Date:   Fri Oct 5 10:27:00 2018 +0100

    drm/fourcc: Add AFBC yuv fourccs for Mali

and

commit 50bf5d7d595fd0705ef3785f80e679b6da501e5b
Author: Swati Sharma &lt;swati2.sharma@intel.com&gt;
Date:   Mon Mar 4 17:26:33 2019 +0530

    drm: Add Y2xx and Y4xx (xx:10/12/16) format definitions and fourcc

Unfortunately gcc didn't warn about the redefinitions, because the
double defines were the set to same value, and gcc apparently no longer
warns about that.

Fix this by using new XYVU for i915, without alpha, and making the
Y41x definitions match msdn, with alpha.

Fortunately we caught it early, and the conflict hasn't even landed in
drm-next yet.

Signed-off-by: Maarten Lankhorst &lt;maarten.lankhorst@linux.intel.com&gt;
Cc: Brian Starkey &lt;Brian.Starkey@arm.com&gt;
Cc: Swati Sharma &lt;swati2.sharma@intel.com&gt;
Cc: Ayan Kumar Halder &lt;ayan.halder@arm.com&gt;
Cc: malidp@foss.arm.com
Cc: Daniel Vetter &lt;daniel@ffwll.ch&gt;
Cc: Maxime Ripard &lt;maxime.ripard@bootlin.com&gt;
Cc: Sean Paul &lt;sean@poorly.run&gt;
Cc: Dave Airlie &lt;airlied@linux.ie&gt;
Cc: Liviu Dudau &lt;Liviu.Dudau@arm.com&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/20190319121702.6814-1-maarten.lankhorst@linux.intel.com
Acked-by: Jani Nikula &lt;jani.nikula@intel.com&gt; #irc
Acked-by: Sean Paul &lt;sean@poorly.run&gt;
Reviewed-by: Ayan Kumar halder &lt;ayan.halder@arm.com&gt;
</content>
</entry>
<entry>
<title>Merge tag 'topic/hdr-formats-2019-03-13' of git://anongit.freedesktop.org/drm/drm-misc into drm-misc-next</title>
<updated>2019-03-13T18:08:05+00:00</updated>
<author>
<name>Sean Paul</name>
<email>seanpaul@chromium.org</email>
</author>
<published>2019-03-13T18:07:32+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=f435fe83d56b8b804c4204246bccba7749f605f9'/>
<id>urn:sha1:f435fe83d56b8b804c4204246bccba7749f605f9</id>
<content type='text'>
Add support for floating point half-width formats.

Signed-off-by: Sean Paul &lt;seanpaul@chromium.org&gt;

From: Maarten Lankhorst &lt;maarten.lankhorst@linux.intel.com&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/00b96cd5-91c7-5677-9620-b138c7a92303@linux.intel.com
</content>
</entry>
<entry>
<title>drm/fourcc: Add 64 bpp half float formats</title>
<updated>2019-03-13T10:10:31+00:00</updated>
<author>
<name>Kevin Strasser</name>
<email>kevin.strasser@intel.com</email>
</author>
<published>2019-03-13T00:38:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=88ab9c76d191ad8645b483f31e2b394b0f3e280e'/>
<id>urn:sha1:88ab9c76d191ad8645b483f31e2b394b0f3e280e</id>
<content type='text'>
Add 64 bpp 16:16:16:16 half float pixel formats. Each 16 bit component is
formatted in IEEE-754 half-precision float (binary16) 1:5:10
MSb-sign:exponent:fraction form.

This patch attempts to address the feedback provided when 2 of these
formats were previosly proposed:
  https://patchwork.kernel.org/patch/10072545/

v2:
- Fixed cpp (Ville)
- Added detail pixel formatting (Ville)
- Ordered formats in header (Ville)

v5:
- .depth should be 0 for new formats (Maarten)

Cc: Tina Zhang &lt;tina.zhang@intel.com&gt;
Cc: Uma Shankar &lt;uma.shankar@intel.com&gt;
Cc: Shashank Sharma &lt;shashank.sharma@intel.com&gt;
Cc: David Airlie &lt;airlied@linux.ie&gt;
Cc: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Cc: dri-devel@lists.freedesktop.org
Signed-off-by: Kevin Strasser &lt;kevin.strasser@intel.com&gt;
Reviewed-by: Ville Syrjälä &lt;ville.syrjala@linux.intel.com&gt;
Reviewed-by: Maarten Lankhorst &lt;maarten.lankhorst@linux.intel.com&gt;
Reviewed-by: Adam Jackson &lt;ajax@redhat.com&gt;
Signed-off-by: Maarten Lankhorst &lt;maarten.lankhorst@linux.intel.com&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/1552437513-22648-2-git-send-email-kevin.strasser@intel.com
</content>
</entry>
<entry>
<title>drm: Added a new format DRM_FORMAT_XVYU2101010</title>
<updated>2019-03-12T18:25:05+00:00</updated>
<author>
<name>Ayan Kumar Halder</name>
<email>ayan.halder@arm.com</email>
</author>
<published>2018-11-09T17:21:12+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=e9961ab95af81b8d29054361cd5f0c575102cf87'/>
<id>urn:sha1:e9961ab95af81b8d29054361cd5f0c575102cf87</id>
<content type='text'>
This new format is supported by DP550 and DP650

Changes since v3 (series):
- Added the ack
- Rebased on the latest drm-misc-next

Signed-off-by: Ayan Kumar halder &lt;ayan.halder@arm.com&gt;
Reviewed-by: Liviu Dudau &lt;liviu.dudau@arm.com&gt;
Acked-by: Alyssa Rosenzweig &lt;alyssa@rosenzweig.io&gt;
Link: https://patchwork.freedesktop.org/patch/291758/?series=57895&amp;rev=1
</content>
</entry>
<entry>
<title>drm/fourcc: Add AFBC yuv fourccs for Mali</title>
<updated>2019-03-12T18:24:55+00:00</updated>
<author>
<name>Brian Starkey</name>
<email>brian.starkey@arm.com</email>
</author>
<published>2018-10-05T09:27:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=7ba0fee247ee7a36b3bfbed68f6988d980aa3aa3'/>
<id>urn:sha1:7ba0fee247ee7a36b3bfbed68f6988d980aa3aa3</id>
<content type='text'>
As we look to enable AFBC using DRM format modifiers, we run into
problems which we've historically handled via vendor-private details
(i.e. gralloc, on Android).

AFBC (as an encoding) is fully flexible, and for example YUV data can
be encoded into 1, 2 or 3 encoded "planes", much like the linear
equivalents. Component order is also meaningful, as AFBC doesn't
necessarily care about what each "channel" of the data it encodes
contains. Therefore ABGR8888 and RGBA8888 can be encoded in AFBC with
different representations. Similarly, 'X' components may be encoded
into AFBC streams in cases where a decoder expects to decode a 4th
component.

In addition, AFBC is a licensable IP, meaning that to support the
ecosystem we need to ensure that _all_ AFBC users are able to describe
the encodings that they need. This is much better achieved by
preserving meaning in the fourcc codes when they are combined with an
AFBC modifier.

In essence, we want to use the modifier to describe the parameters of
the AFBC encode/decode, and use the fourcc code to describe the data
being encoded/decoded.

To do anything different would be to introduce redundancy - we would
need to duplicate in the modifier information which is _already_
conveyed clearly and non-ambigiously by a fourcc code.

I hope that for RGB this is non-controversial.
(BGRA8888 + MODIFIER_AFBC) is a different format from
(RGBA8888 + MODIFIER_AFBC).

Possibly more controversial is that (XBGR8888 + MODIFIER_AFBC)
is different from (BGR888 + MODIFIER_AFBC). I understand that in some
schemes it is not the case - but in AFBC it is so.

Where we run into problems is where there are not already fourcc codes
which represent the data which the AFBC encoder/decoder is processing.
To that end, we want to introduce new fourcc codes to describe the
data being encoded/decoded, in the places where none of the existing
fourcc codes are applicable.

Where we don't support an equivalent non-compressed layout, or where
no "obvious" linear layout exists, we are proposing adding fourcc
codes which have no associated linear layout - because any layout we
proposed would be completely arbitrary.

Some formats are following the naming conventions from [2].

The summary of the new formats is:
 DRM_FORMAT_VUY888 - Packed 8-bit YUV 444. Y followed by U then V.
 DRM_FORMAT_VUY101010 - Packed 10-bit YUV 444. Y followed by U then
                        V. No defined linear encoding.
 DRM_FORMAT_Y210 - Packed 10-bit YUV 422. Y followed by U (then Y)
                   then V. 10-bit samples in 16-bit words.
 DRM_FORMAT_Y410 - Packed 10-bit YUV 444, with 2-bit alpha.
 DRM_FORMAT_P210 - Semi-planar 10-bit YUV 422. Y plane, followed by
                   interleaved U-then-V plane. 10-bit samples in
                   16-bit words.
 DRM_FORMAT_YUV420_8BIT - Packed 8-bit YUV 420. Y followed by U then
                          V. No defined linear encoding
 DRM_FORMAT_YUV420_10BIT - Packed 10-bit YUV 420. Y followed by U
                           then V. No defined linear encoding

Please also note that in the absence of AFBC, we would still need to
add Y410, Y210 and P210.

Full rationale follows:

YUV 444 8-bit, 1-plane
----------------------
 The currently defined AYUV format encodes a 4th alpha component,
 which makes it unsuitable for representing a 3-component YUV 444
 AFBC stream.

 The proposed[1] XYUV format which is supported by Mali-DP in linear
 layout is also unsuitable, because the component order is the
 opposite of the AFBC version, and it encodes a 4th 'X' component.

 DRM_FORMAT_VUY888 is the "obvious" format for a 3-component, packed,
 YUV 444 8-bit format, with the component order which our HW expects to
 encode/decode. It conforms to the same naming convention as the
 existing packed YUV 444 format.
 The naming here is meant to be consistent with DRM_FORMAT_AYUV and
 DRM_FORMAT_XYUV[1]

YUV 444 10-bit, 1-plane
-----------------------
 There is no currently-defined YUV 444 10-bit format in
 drm_fourcc.h, irrespective of number of planes.

 The proposed[1] XVYU2101010 format which is supported by Mali-DP in
 linear layout uses the wrong component order, and also encodes a 4th
 'X' component, which doesn't match the AFBC version of YUV 444
 10-bit which we support.

 DRM_FORMAT_Y410 is the same layout as XVYU2101010, but with 2 bits of
 alpha.  This format is supported with linear layout by Mali GPUs. The
 naming follows[2].

 There is no "obvious" linear encoding for a 3-component 10:10:10
 packed format, and so DRM_FORMAT_VUY101010 defines a component
 order, but not a bit encoding. Again, the naming is meant to be
 consistent with DRM_FORMAT_AYUV.

YUV 422 8-bit, 1-plane
----------------------
 The existing DRM_FORMAT_YUYV (and the other component orders) are
 single-planar YUV 422 8-bit formats. Following the convention of
 the component orders of the RGB formats, YUYV has the correct
 component order for our AFBC encoding (Y followed by U followed by
 V). We can use YUYV for AFBC YUV 422 8-bit.

YUV 422 10-bit, 1-plane
-----------------------
 There is no currently-defined YUV 422 10-bit format in drm_fourcc.h

 DRM_FORMAT_Y210 is analogous to YUYV, but with 10-bits per sample
 packed into the upper 10-bits of 16-bit samples. This format is
 supported in both linear and AFBC by Mali GPUs.

YUV 422 10-bit, 2-plane
-----------------------
 The recently defined DRM_FORMAT_P010 format is a 10-bit semi-planar
 YUV 420 format, which has the correct component ordering for an AFBC
 2-plane YUV 420 buffer. The linear layout contains meaningless padding
 bits, which will not be encoded in an AFBC stream.

YUV 420 8-bit, 1-plane
----------------------
 There is no currently defined single-planar YUV 420, 8-bit format
 in drm_fourcc.h. There's differing opinions on whether using the
 existing fourcc-implied n_planes where possible is a good idea or
 not when using modifiers.

 For me, it's much more "obvious" to use NV12 for 2-plane AFBC and
 YUV420 for 3-plane AFBC. This keeps the aforementioned separation
 between the AFBC codec settings (in the modifier) and the pixel data
 format (in the fourcc). With different vendors using AFBC, this helps
 to ensure that there is no confusion in interoperation. It also
 ensures that the AFBC modifiers describe AFBC itself (which is a
 licensable component), and not implementation details which are not
 defined by AFBC.

 The proposed[1] X0L0 format which Mali-DP supports with Linear layout
 is unsuitable, as it contains a 4th 'X' component, and our AFBC
 decoder expects only 3 components.

 To that end, we propose a new YUV 420 8-bit format. There is no
 "obvious" linear encoding for a 3-component 8:8:8, 420, packed format,
 and so DRM_FORMAT_YUV420_8BIT defines a component order, but not a
 bit encoding. I'm happy to hear different naming suggestions.

YUV 420 8-bit, 2-, 3-plane
--------------------------
 These already exist, we can use NV12 and YUV420.

YUV 420 10-bit, 1-plane
-----------------------
 As above, no current definition exists, and X0L2 encodes a 4th 'X'
 channel.

 Analogous to DRM_FORMAT_YUV420_8BIT, we define DRM_FORMAT_YUV420_10BIT.

[1] https://lists.freedesktop.org/archives/dri-devel/2018-July/184598.html
[2] https://docs.microsoft.com/en-us/windows/desktop/medfound/10-bit-and-16-bit-yuv-video-formats

Changes since RFC v1:
 - Fix confusing subsampling vs bit-depth X:X:X notation in
   descriptions (danvet)
 - Rename DRM_FORMAT_AVYU1101010 to DRM_FORMAT_Y410 (Lisa Wu)
 - Add drm_format_info structures for the new formats, using the
   new 'bpp' field for those with non-integer bytes-per-pixel
 - Rebase, including Juha-Pekka Heikkila's format definitions

Changes since RFC v2:
- Rebase on top of latest changes in drm-misc-next
- Change the description of DRM_FORMAT_P210 in __drm_format_info and
drm_fourcc.h so as to make it consistent with other DRM_FORMAT_PXXX
formats.

Changes since v3:
- Added the ack
- Rebased on the latest drm-misc-next

Signed-off-by: Brian Starkey &lt;brian.starkey@arm.com&gt;
Signed-off-by: Ayan Kumar Halder &lt;ayan.halder@arm.com&gt;
Reviewed-by: Liviu Dudau &lt;liviu.dudau@arm.com&gt;
Acked-by: Alyssa Rosenzweig &lt;alyssa@rosenzweig.io&gt;
Link: https://patchwork.freedesktop.org/patch/291759/?series=57895&amp;rev=1
</content>
</entry>
<entry>
<title>drm: Add Y2xx and Y4xx (xx:10/12/16) format definitions and fourcc</title>
<updated>2019-03-05T11:47:54+00:00</updated>
<author>
<name>Swati Sharma</name>
<email>swati2.sharma@intel.com</email>
</author>
<published>2019-03-04T11:56:33+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=50bf5d7d595fd0705ef3785f80e679b6da501e5b'/>
<id>urn:sha1:50bf5d7d595fd0705ef3785f80e679b6da501e5b</id>
<content type='text'>
The following pixel formats are packed format that follows 4:2:2
chroma sampling. For memory represenation each component is
allocated 16 bits each. Thus each pixel occupies 32bit.

Y210:	For each component, valid data occupies MSB 10 bits.
	LSB 6 bits are filled with zeroes.
Y212:	For each component, valid data occupies MSB 12 bits.
	LSB 4 bits are filled with zeroes.
Y216:	For each component valid data occupies 16 bits,
	doesn't require any padding bits.

First 16 bits stores the Y value and the next 16 bits stores one
of the chroma samples alternatively. The first luma sample will
be accompanied by first U sample and second luma sample is
accompanied by the first V sample.

The following pixel formats are packed format that follows 4:4:4
chroma sampling. Channels are arranged in the order UYVA in
increasing memory order.

Y410:	Each color component occupies 10 bits and X component
	takes 2 bits, thus each pixel occupies 32 bits.
Y412:   Each color component is 16 bits where valid data
	occupies MSB 12 bits. LSB 4 bits are filled with zeroes.
	Thus, each pixel occupies 64 bits.
Y416:   Each color component occupies 16 bits for valid data,
	doesn't require any padding bits. Thus, each pixel
	occupies 64 bits.

v3: fixed missing tab for XYUV8888 (JP)

Signed-off-by: Swati Sharma &lt;swati2.sharma@intel.com&gt;
Signed-off-by: Vidya Srinivas &lt;vidya.srinivas@intel.com&gt;
Reviewed-by: Juha-Pekka Heikkila &lt;juhapekka.heikkila@gmail.com&gt;
Signed-off-by: Maarten Lankhorst &lt;maarten.lankhorst@linux.intel.com&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/1551700595-21481-5-git-send-email-swati2.sharma@intel.com
</content>
</entry>
<entry>
<title>drm/fourcc: Add new P010, P016 video format</title>
<updated>2019-02-08T21:17:08+00:00</updated>
<author>
<name>Randy Li</name>
<email>ayaka@soulik.info</email>
</author>
<published>2019-01-09T19:57:09+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=05f8bc82fc428dbaf41764e95167dd759769f33d'/>
<id>urn:sha1:05f8bc82fc428dbaf41764e95167dd759769f33d</id>
<content type='text'>
P010 is a planar 4:2:0 YUV with interleaved UV plane, 10 bits per
channel video format.

P012 is a planar 4:2:0 YUV 12 bits per channel

P016 is a planar 4:2:0 YUV with interleaved UV plane, 16 bits per
channel video format.

V3: Added P012 and fixed cpp for P010.
V4: format definition refined per review.
V5: Format comment block for each new pixel format.
V6: reversed Cb/Cr order in comments.
v7: reversed Cb/Cr order in comments of header files, remove
the wrong part of commit message.
V8: reversed V7 changes except commit message and rebased.
v9: used the new properties to describe those format and
rebased.

Cc: Daniel Stone &lt;daniel@fooishbar.org&gt;
Cc: Ville Syrjälä &lt;ville.syrjala@linux.intel.com&gt;

Signed-off-by: Randy Li &lt;ayaka@soulik.info&gt;
Signed-off-by: Clint Taylor &lt;clinton.a.taylor@intel.com&gt;
Reviewed-by: Ayan Kumar Halder &lt;ayan.halder@arm.com&gt;
Reviewed-by: Neil Armstrong &lt;narmstrong@baylibre.com&gt;
Reviewed-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Signed-off-by: Neil Armstrong &lt;narmstrong@baylibre.com&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/20190109195710.28501-2-ayaka@soulik.info
</content>
</entry>
<entry>
<title>drm: Introduce new DRM_FORMAT_XYUV</title>
<updated>2018-11-20T14:20:13+00:00</updated>
<author>
<name>Stanislav Lisovskiy</name>
<email>stanislav.lisovskiy@intel.com</email>
</author>
<published>2018-11-09T09:39:15+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=61e49394a31aee438e026e553a1422e13e0309d9'/>
<id>urn:sha1:61e49394a31aee438e026e553a1422e13e0309d9</id>
<content type='text'>
v5: This is YUV444 packed format same as AYUV, but without alpha,
    as supported by i915.

v6: Removed unneeded initializer for new XYUV format.

v7: Added is_yuv field initialization according to latest
    drm_fourcc format structure initialization changes.

v8: Edited commit message to be more clear about skl+, renamed
    PLANE_CTL_FORMAT_AYUV to PLANE_CTL_FORMAT_XYUV as this format
    doesn't support per-pixel alpha. Fixed minor code issues.

v9: Moved DRM format check to proper place in intel_framebuffer_init.

v10: Changed DRM_FORMAT_XYUV to be DRM_FORMAT_XYUV8888

v11: Fixed rebase conflict, caused by added new formats to drm-tip
     meanwhile.

Reviewed-by: Alexandru Gheorghe &lt;alexandru-cosmin.gheorghe@arm.com&gt;
Signed-off-by: Stanislav Lisovskiy &lt;stanislav.lisovskiy@intel.com&gt;
[vsyrjala: Removed stray tab and sorted the formats differently]
Signed-off-by: Ville Syrjälä &lt;ville.syrjala@linux.intel.com&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/20181109093916.25858-2-stanislav.lisovskiy@intel.com
</content>
</entry>
<entry>
<title>drm/fourcc: Add fourcc for Mali linear tiled formats</title>
<updated>2018-11-02T09:55:44+00:00</updated>
<author>
<name>Alexandru Gheorghe</name>
<email>alexandru-cosmin.gheorghe@arm.com</email>
</author>
<published>2018-11-01T15:11:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=697b6b85042ef0fb9838e3100700eed727c211e9'/>
<id>urn:sha1:697b6b85042ef0fb9838e3100700eed727c211e9</id>
<content type='text'>
Mali-DP implements a number of tiled yuv formats which are not
currently described in drm_fourcc.h.
This adds those definitions and describes their memory layout by
using the newly added char_per_block, block_w, block_h.

Reviewed-by: Brian Starkey &lt;brian.starkey@arm.com&gt;
Reviewed-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Signed-off-by: Alexandru Gheorghe &lt;alexandru-cosmin.gheorghe@arm.com&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/20181101151051.1509-3-alexandru-cosmin.gheorghe@arm.com
</content>
</entry>
<entry>
<title>drm/fourcc: Add char_per_block, block_w and block_h in drm_format_info</title>
<updated>2018-11-02T09:55:27+00:00</updated>
<author>
<name>Alexandru Gheorghe</name>
<email>alexandru-cosmin.gheorghe@arm.com</email>
</author>
<published>2018-11-01T17:02:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=042bf753842ddbddcf3d4c29f21a8905d6a33e79'/>
<id>urn:sha1:042bf753842ddbddcf3d4c29f21a8905d6a33e79</id>
<content type='text'>
For some pixel formats .cpp structure in drm_format info it's not
enough to describe the peculiarities of the pixel layout, for example
tiled formats or packed formats at bit level.

What's implemented here is to add three new members to drm_format_info
that could describe such formats:

- char_per_block[3]
- block_w[3]
- block_h[3]

char_per_block will be put in a union alongside cpp, for transparent
compatibility  with the existing format descriptions.

Regarding, block_w and block_h they are intended to be used through
their equivalent getters drm_format_info_block_width /
drm_format_info_block_height, the reason of the getters is to abstract
the fact that for normal formats block_w and block_h will be unset/0,
but the methods will be returning 1.

Additionally, convenience function drm_format_info_min_pitch had been
added that computes the minimum required pitch for a given pixel
format and buffer width.

Using that the following drm core functions had been updated to
generically handle both block and non-block formats:

- drm_fb_cma_get_gem_addr: for block formats it will just return the
  beginning of the block.
- framebuffer_check: Use the newly added drm_format_info_min_pitch.
- drm_gem_fb_create_with_funcs: Use the newly added
  drm_format_info_min_pitch.
- In places where is not expecting to handle block formats, like fbdev
  helpers I just added some warnings in case the block width/height
  are greater than 1.

Changes since v3:
 - Add helper function for computing the minimum required pitch.
 - Improve/cleanup documentation

Changes since v8:
 - Fixed build on 32bits arm architectures, with:

-       return DIV_ROUND_UP((u64)buffer_width * info-&gt;char_per_block[plane],
+       return DIV_ROUND_UP_ULL((u64)buffer_width * info-&gt;char_per_block[plane],

Reviewed-by: Brian Starkey &lt;brian.starkey@arm.com&gt;
Reviewed-by: Daniel Vetter &lt;daniel.vetter@ffwll.ch&gt;
Signed-off-by: Alexandru Gheorghe &lt;alexandru-cosmin.gheorghe@arm.com&gt;
Link: https://patchwork.freedesktop.org/patch/msgid/20181101170055.5433-1-alexandru-cosmin.gheorghe@arm.com
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