No description
  • C 98.2%
  • Assembly 1%
  • Makefile 0.3%
  • Shell 0.2%
  • Python 0.1%
Find a file
Repository files (latest commit first)
Filename Latest commit message Latest commit date
Nicholas Kazlauskas 6752bea8b0 drm/amd/display: Prevent cursor hotspot overflow for RV overlay planes
[Why]
The actual position for the cursor on the screen is essentially:

x_out = x - x_plane - x_hotspot
y_out = y - y_plane - y_hotspot

The register values for cursor position and cursor hotspot need to be
greater than zero when programmed, but we also need to subtract off
the plane position to display the cursor at the correct position.

Since we don't want x or y to be less than zero, we add the plane
position as a positive value to x_hotspot or y_hotspot. However, what
this doesn't take into account is that the hotspot registers are limited
by the maximum cursor size.

On DCN10 the cursor hotspot regitsers are masked to 0xFF, so they have
a maximum value of 0-255. Values greater this will wrap, causing the
cursor to display in the wrong position.

In practice this means that for sufficiently large plane positions, the
cursor will be drawn twice on the screen, and can cause screen flashes
or p-state WARNS depending on what the wrapped value is.

So we need a way to remove the value from x_plane and y_plane without
exceeding the maximum cursor size.

[How]
Subtract as much as x_plane/y_plane as possible from x and y and place
the remainder in the cursor hotspot register.

The value for x_hotspot and y_hotspot can still wrap around but it
won't happen in a case where the cursor is actually enabled.

The cursor plane needs to intersect at least one pixel of the plane's
rectangle to be enabled, so the cursor position + hotspot provided by
userspace must always be strictly less than the maximum cursor size for
the cursor to actually be enabled.

Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Reviewed-by: Sun peng Li <Sunpeng.Li@amd.com>
Acked-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2019-04-03 11:57:22 -05:00
arch Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-03-24 11:12:27 -07:00
block io_uring-20190323 2019-03-23 10:25:12 -07:00
certs
crypto
Documentation drm-misc-next for 5.2: 2019-03-29 14:03:01 +10:00
drivers drm/amd/display: Prevent cursor hotspot overflow for RV overlay planes 2019-04-03 11:57:22 -05:00
fs Miscellaneous ext4 bug fixes for 5.1. 2019-03-24 13:41:37 -07:00
include Merge branch 'drm-next-5.2' of git://people.freedesktop.org/~agd5f/linux into drm-next 2019-04-03 13:26:11 +10:00
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 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-03-24 11:42:10 -07:00
lib Kbuild updates for v5.1 (2nd) 2019-03-17 13:25:26 -07:00
LICENSES
mm device-dax for 5.1 2019-03-16 13:05:32 -07:00
net libceph: wait for latest osdmap in ceph_monc_blacklist_add() 2019-03-20 16:27:40 +01:00
samples Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-03-11 08:54:01 -07:00
scripts kconfig: remove stale lxdialog/.gitignore 2019-03-17 15:47:02 +09:00
security selinux: fix NULL dereference in policydb_destroy() 2019-03-18 12:19:48 -04:00
sound Merge drm/drm-next into drm-intel-next-queued 2019-03-27 18:23:53 +02:00
tools Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-03-24 11:16:27 -07:00
usr
virt ARM: some cleanups, direct physical timer assignment, cache sanitization 2019-03-15 15:00:28 -07:00
.clang-format Merge branch 'work.iov_iter' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2019-03-12 13:43:42 -07:00
.cocciconfig
.get_maintainer.ignore
.gitattributes
.gitignore
.mailmap
COPYING
CREDITS
Kbuild Kbuild updates for v5.1 2019-03-10 17:48:21 -07:00
Kconfig
MAINTAINERS Merge commit 'refs/for-upstream/mali-dp' of git://linux-arm.org/linux-ld into drm-next 2019-04-03 13:44:40 +10:00
Makefile Linux 5.1-rc2 2019-03-24 14:02:26 -07:00
README

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.