linux-stable/drivers/gpu/drm
Mario Kleiner 07f18f0bb8 drm/radeon: Handle irqs only based on irq ring, not irq status regs.
Trying to resolve issues with missed vblanks and impossible
values inside delivered kms pageflip completion events showed
that radeon's irq handling sometimes doesn't handle valid irqs,
but silently skips them. This was observed for vblank interrupts.

Although those irqs have corresponding events queued in the gpu's
irq ring at time of interrupt, and therefore the corresponding
handling code gets triggered by these events, the handling code
sometimes silently skipped processing the irq. The reason for those
skips is that the handling code double-checks for each irq event if
the corresponding irq status bits in the irq status registers
are set. Sometimes those bits are not set at time of check
for valid irqs, maybe due to some hardware race on some setups?

The problem only seems to happen on some machine + card combos
sometimes, e.g., never happened during my testing of different PC
cards of the DCE-2/3/4 generation a year ago, but happens consistently
now on two different Apple Mac cards (RV730, DCE-3, Apple iMac and
Evergreen JUNIPER, DCE-4 in a Apple MacPro). It also doesn't happen
at each interrupt but only occassionally every couple of
hundred or thousand vblank interrupts.

This results in XOrg warning messages like

"[  7084.472] (WW) RADEON(0): radeon_dri2_flip_event_handler:
Pageflip completion event has impossible msc 420120 < target_msc 420121"

as well as skipped frames and problems for applications that
use kms pageflip events or vblank events, e.g., users of DRI2 and
DRI3/Present, Waylands Weston compositor, etc. See also

https://bugs.freedesktop.org/show_bug.cgi?id=85203

After some talking to Alex and Michel, we decided to fix this
by turning the double-check for asserted irq status bits into a
warning. Whenever a irq event is queued in the IH ring, always
execute the corresponding interrupt handler. Still check the irq
status bits, but only to log a DRM_DEBUG message on a mismatch.

This fixed the problems reliably on both previously failing
cards, RV-730 dual-head tested on both crtcs (pipes D1 and D2)
and a triple-output Juniper HD-5770 card tested on all three
available crtcs (D1/D2/D3). The r600 and evergreen irq handling
is therefore tested, but the cik an si handling is only compile
tested due to lack of hw.

Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Mario Kleiner <mario.kleiner.de@gmail.com>
CC: Michel Dänzer <michel.daenzer@amd.com>
CC: Alex Deucher <alexander.deucher@amd.com>
CC: <stable@vger.kernel.org> # v3.16+
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
2015-07-08 12:41:36 -04:00
..
amd Merge branch 'drm-next-4.2' of git://people.freedesktop.org/~agd5f/linux 2015-07-02 14:38:15 -07:00
armada
ast
atmel-hlcdc
bochs
bridge drm/exynos: atomic dpms support 2015-06-20 00:32:52 +09:00
cirrus
exynos drm/exynos: dsi: do not set TE GPIO direction by input 2015-06-22 20:05:03 +09:00
gma500
i2c Merge branch 'drm-tda998x-devel' of git://ftp.arm.linux.org.uk/~rmk/linux-arm into drm-next 2015-05-29 09:19:59 +10:00
i810
i915 Merge tag 'drm-intel-next-fixes-2015-07-02' of git://anongit.freedesktop.org/drm-intel 2015-07-02 14:36:40 -07:00
imx
mga
mgag200 drm/mgag200: Reject non-character-cell-aligned mode widths 2015-06-16 10:01:16 +10:00
msm drm/msm: restart queued submits after hang 2015-06-11 13:11:06 -04:00
nouveau drm/nouveau/gem: use kvfree() in u_free() 2015-06-30 19:44:59 -07:00
omapdrm drm: omapdrm: new vblank and event handling 2015-06-12 23:30:47 +03:00
panel drm/panel: simple: Add bus format for HannStar HSD100PXN1 2015-06-12 16:40:42 +02:00
qxl drm/qxl: Propagate correctly errors from qxlhw_handle_to_bo 2015-06-05 11:00:52 +10:00
r128
radeon drm/radeon: Handle irqs only based on irq ring, not irq status regs. 2015-07-08 12:41:36 -04:00
rcar-du drm: rcar-du: Use the drm atomic state duplication helpers for planes 2015-06-16 14:25:55 +03:00
rockchip drivers/gpu: include <module.h> for modular rockchip code 2015-06-16 14:12:25 -04:00
savage
shmobile
sis
sti drm/sti: vtg fix CEA-861E video format timing error 2015-06-08 15:28:28 +02:00
tdfx
tegra drm/tegra: Changes for v4.2-rc1 2015-06-18 12:53:54 +10:00
tilcdc drm/tilcdc: Add DRM_TILCDC_SLAVE_COMPAT for ti,tilcdc,slave binding support 2015-05-27 13:13:33 +03:00
ttm drm/ttm: dma: Don't crash on memory in the vmalloc range 2015-06-02 17:24:49 +10:00
udl
vgem drm/vgem: Set unique to "vgem" 2015-06-24 11:20:46 +10:00
via
virtio virtio-gpu: add locking for vbuf pool 2015-06-16 11:22:41 +02:00
vmwgfx
ati_pcigart.c
drm_agpsupport.c
drm_atomic.c drm/atomic: Extract needs_modeset function 2015-06-19 17:25:01 +02:00
drm_atomic_helper.c drm/atomic: Don't set crtc_state->enable manually 2015-06-22 13:45:33 +02:00
drm_auth.c
drm_bridge.c drm/DocBook: Add more drm_bridge documentation 2015-05-21 13:56:51 +02:00
drm_bufs.c
drm_cache.c drm: Avoid the double clflush on the last cache line in drm_clflush_virt_range() 2015-06-19 17:25:17 +02:00
drm_context.c
drm_crtc.c drm/crtc: Fix edid length computation 2015-07-04 00:52:34 +02:00
drm_crtc_helper.c drm: Add drm_atomic_set_mode_for_crtc 2015-05-26 15:50:34 +02:00
drm_crtc_internal.h
drm_debugfs.c
drm_dma.c
drm_dp_helper.c
drm_dp_mst_topology.c drm/dp/mst: close deadlock in connector destruction. 2015-06-25 11:57:23 +10:00
drm_drv.c drm: Always enable atomic API 2015-06-24 11:21:35 +10:00
drm_edid.c
drm_edid_load.c
drm_encoder_slave.c
drm_fb_cma_helper.c
drm_fb_helper.c
drm_flip_work.c
drm_fops.c drm/mode: Add user blob-creation ioctl 2015-05-22 16:18:28 +02:00
drm_gem.c
drm_gem_cma_helper.c drm/cma: Fix 64-bit size_t build warnings 2015-06-15 07:45:49 +02:00
drm_global.c
drm_hashtab.c
drm_info.c
drm_internal.h
drm_ioc32.c
drm_ioctl.c Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux 2015-06-26 13:18:51 -07:00
drm_irq.c Merge branch 'virtio-gpu-drm-next' of git://git.kraxel.org/linux into drm-next 2015-06-04 09:36:39 +10:00
drm_legacy.h
drm_lock.c
drm_memory.c
drm_mipi_dsi.c
drm_mm.c drm: clean up drm_mm debugfs output 2015-05-29 09:17:57 +10:00
drm_modes.c drm/mode: Unstatic kernel-userspace mode conversion 2015-05-22 16:18:21 +02:00
drm_modeset_lock.c
drm_of.c
drm_panel.c
drm_pci.c
drm_plane_helper.c drm/plane-helper: Adapt cursor hack to transitional helpers 2015-05-22 08:48:08 +03:00
drm_platform.c
drm_prime.c drm: prime: Document gem_prime_mmap 2015-06-19 17:50:05 +02:00
drm_probe_helper.c
drm_rect.c
drm_scatter.c
drm_sysfs.c Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux 2015-06-26 13:18:51 -07:00
drm_trace.h
drm_trace_points.c
drm_vm.c
drm_vma_manager.c
Kconfig drm/amdgpu: add core driver (v4) 2015-06-03 21:03:15 -04:00
Makefile drm/amdgpu: add core driver (v4) 2015-06-03 21:03:15 -04:00