linux/include
Daniel Vetter 1bf6ad622b drm/vblank: drop the mode argument from drm_calc_vbltimestamp_from_scanoutpos
If we restrict this helper to only kms drivers (which is the case) we
can look up the correct mode easily ourselves. But it's a bit tricky:

- All legacy drivers look at crtc->hwmode. But that is updated already
  at the beginning of the modeset helper, which means when we disable
  a pipe. Hence the final timestamps might be a bit off. But since
  this is an existing bug I'm not going to change it, but just try to
  be bug-for-bug compatible with the current code. This only applies
  to radeon&amdgpu.

- i915 tries to get it perfect by updating crtc->hwmode when the pipe
  is off (i.e. vblank->enabled = false).

- All other atomic drivers look at crtc->state->adjusted_mode. Those
  that look at state->requested_mode simply don't adjust their mode,
  so it's the same. That has two problems: Accessing crtc->state from
  interrupt handling code is unsafe, and it's updated before we shut
  down the pipe. For nonblocking modesets it's even worse.

For atomic drivers try to implement what i915 does. To do that we add
a new hwmode field to the vblank structure, and update it from
drm_calc_timestamping_constants(). For atomic drivers that's called
from the right spot by the helper library already, so all fine. But
for safety let's enforce that.

For legacy driver this function is only called at the end (oh the
fun), which is broken, so again let's not bother and just stay
bug-for-bug compatible.

The  benefit is that we can use drm_calc_vbltimestamp_from_scanoutpos
directly to implement ->get_vblank_timestamp in every driver, deleting
a lot of code.

v2: Completely new approach, trying to mimick the i915 solution.

v3: Fixup kerneldoc.

v4: Drop the WARN_ON to check that the vblank is off, atomic helpers
currently unconditionally call this. Recomputing the same stuff should
be harmless.

v5: Fix typos and move misplaced hunks to the right patches (Neil).

v6: Undo hunk movement (kbuild).

Cc: Mario Kleiner <mario.kleiner@tuebingen.mpg.de>
Cc: Eric Anholt <eric@anholt.net>
Cc: Rob Clark <robdclark@gmail.com>
Cc: linux-arm-msm@vger.kernel.org
Cc: freedreno@lists.freedesktop.org
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Acked-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170509140329.24114-4-daniel.vetter@ffwll.ch
2017-05-10 10:21:31 +02:00
..
acpi
asm-generic vmlinux.lds: add missing VMLINUX_SYMBOL macros 2017-04-08 00:47:48 -07:00
clocksource
crypto net: Work around lockdep limitation in sockets that use sockets 2017-03-09 18:23:27 -08:00
drm drm/vblank: drop the mode argument from drm_calc_vbltimestamp_from_scanoutpos 2017-05-10 10:21:31 +02:00
dt-bindings scripts/spelling.txt: add "overide" pattern and fix typo instances 2017-03-09 17:01:09 -08:00
keys KEYS: Differentiate uses of rcu_dereference_key() and user_key_payload() 2017-03-02 10:09:00 +11:00
kvm KVM: arm64: Ensure LRs are clear when they should be 2017-04-04 14:33:58 +02:00
linux video: ARM CLCD: Move registers to a separate header. 2017-05-08 12:24:06 -07:00
math-emu
media media fixes for v4.11-rc2 2017-03-09 15:50:56 -08:00
memory
misc
net sctp: get sock from transport in sctp_transport_update_pmtu 2017-04-05 07:20:06 -07:00
pcmcia
ras
rdma IB/core: Restore I/O MMU, s390 and powerpc support 2017-03-24 21:51:16 -04:00
rxrpc
scsi scsi: mpt3sas: Avoid sleeping in interrupt context 2017-03-01 21:52:13 -05:00
soc
sound sched/headers: Prepare to remove spurious <linux/sched.h> inclusion dependencies 2017-03-02 08:42:41 +01:00
target target: Fix ALUA transition state race between multiple initiators 2017-03-30 23:12:40 -07:00
trace There was some breakage with the changes for jump labels in the 4.11 merge 2017-03-07 09:37:28 -08:00
uapi Linux 4.11-rc7 2017-04-19 11:07:14 +10:00
video Linux 4.11-rc4 2017-03-28 17:34:19 +10:00
xen Merge branch 'stable/for-linus-4.11' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb 2017-03-07 10:23:17 -08:00
Kbuild