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Gwan-gyeong Mun 16668f486f drm/i915/dp: Change a link bandwidth computation for DP
Data M/N calculations were assumed a bpp as RGB format. But when we are
using YCbCr 4:2:0 output format on DP, we should change bpp calculations
as YCbCr 4:2:0 format. The pipe_bpp value was assumed RGB format,
therefore, it was multiplied with 3. But YCbCr 4:2:0 requires a multiplier
value to 1.5.
Therefore we need to divide pipe_bpp to 2 while DP output uses YCbCr4:2:0
format.
 - RGB format bpp = bpc x 3
 - YCbCr 4:2:0 format bpp = bpc x 1.5

But Link M/N values are calculated and applied based on the Full Clock for
YCbCr 4:2:0. And DP YCbCr 4:2:0 does not need to pixel clock double for
a dotclock caluation. Only for HDMI YCbCr 4:2:0 needs to pixel clock double
for a dot clock calculation.

It only affects dp and edp port which use YCbCr 4:2:0 output format.
And for now, it does not consider a use case of DSC + YCbCr 4:2:0.

v2:
  Addressed review comments from Ville.
  Remove a changing of pipe_bpp on intel_ddi_set_pipe_settings().
  Because the pipe is running at the full bpp, keep pipe_bpp as RGB
  even though YCbCr 4:2:0 output format is used.
  Add a link bandwidth computation for YCbCr4:2:0 output format.

v3:
  Addressed reivew comments from Ville.
  In order to make codes simple, it adds and uses intel_dp_output_bpp()
  function.

v6:
  Link M/N values are calculated and applied based on the Full Clock for
  YCbCr420. The Bit per Pixel needs to be adjusted for YUV420 mode as it
  requires only half of the RGB case.
    - Link M/N values are calculated and applied based on the Full Clock
    - Data M/N values needs to be calculated considering the data is half
      due to subsampling
  Remove a doubling of pixel clock on a dot clock calculator for
  DP YCbCr 4:2:0.
  Rebase and remove a duplicate setting of vsc_sdp.DB17.
  Add a setting of dynamic range bit to  vsc_sdp.DB17.
  Change Content Type bit to "Graphics" from "Not defined".
  Change a dividing of pipe_bpp to muliplying to constant values on a
  switch-case statement.

v7:
  Addressed review comments from Ville.
  Move a setting of dynamic range bit and a setting of bpc which is based
  on pipe_bpp to a "drm/i915/dp: Program VSC Header and DB for Pixel
  Encoding/Colorimetry Format" commit.
  Change Content Type bit to "Not defined" from "Graphics".

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Gwan-gyeong Mun <gwan-gyeong.mun@intel.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190521121721.32010-6-gwan-gyeong.mun@intel.com
2019-05-23 09:49:44 +03:00
arch Merge tag 'drm-intel-next-2019-04-17' of git://anongit.freedesktop.org/drm/drm-intel into drm-next 2019-04-24 10:02:20 +10:00
block block: do not leak memory in bio_copy_user_iov() 2019-04-10 16:14:40 -06:00
certs kexec, KEYS: Make use of platform keyring for signature verify 2019-02-04 17:34:07 -05:00
crypto lib/lzo: separate lzo-rle from lzo 2019-03-07 18:32:03 -08:00
Documentation drm: revocation check at drm subsystem 2019-05-09 09:44:41 +02:00
drivers drm/i915/dp: Change a link bandwidth computation for DP 2019-05-23 09:49:44 +03:00
fs Merge branch 'page-refs' (page ref overflow) 2019-04-14 15:09:40 -07:00
include drm: Rename struct edp_vsc_psr to struct dp_sdp 2019-05-23 09:49:32 +03:00
init init/main: add checks for the return value of memblock_alloc*() 2019-03-12 10:04:02 -07:00
ipc Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2019-03-12 14:08:19 -07:00
kernel Merge branch 'page-refs' (page ref overflow) 2019-04-14 15:09:40 -07:00
lib Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2019-04-09 16:20:59 -10:00
LICENSES LICENSES: Add GCC runtime library exception text 2019-01-16 14:54:15 -07:00
mm Merge branch 'page-refs' (page ref overflow) 2019-04-14 15:09:40 -07:00
net Revert "SUNRPC: Micro-optimise when the task is known not to be sleeping" 2019-04-11 15:41:14 -04:00
samples Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-03-11 08:54:01 -07:00
scripts fs: stream_open - opener for stream-like files so that read and write can run simultaneously without deadlock 2019-04-06 07:01:55 -10:00
security apparmor: Restore Y/N in /sys for apparmor's "enabled" 2019-04-10 04:24:48 -07:00
sound Linux 5.1-rc5 2019-04-15 15:51:49 +10:00
tools for-linus-20190412 2019-04-13 16:23:16 -07:00
usr user/Makefile: Fix typo and capitalization in comment section 2018-12-11 00:18:03 +09:00
virt KVM/ARM fixes for 5.1 2019-03-28 19:07:30 +01:00
.clang-format clang-format: Update with the latest for_each macro list 2019-04-12 12:49:54 +02:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore kbuild: Add support for DT binding schema checks 2018-12-13 09:41:32 -06:00
.mailmap Update Nicolas Pitre's email address 2019-04-02 18:12:44 -10:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS Char/Misc driver patches for 5.1-rc1 2019-03-06 14:18:59 -08:00
Kbuild Kbuild updates for v5.1 2019-03-10 17:48:21 -07:00
Kconfig kconfig: move the "Executable file formats" menu to fs/Kconfig.binfmt 2018-08-02 08:06:55 +09:00
MAINTAINERS drm-misc-next for v5.2: 2019-04-24 10:12:50 +10:00
Makefile Linux 5.1-rc5 2019-04-14 15:17:41 -07:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.