We have a need to fetch data from GPU-specific sub-devices that is not
tied to any particular engine object.
This commit provides the framework to support such queries.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
This will be required to support Volta, but also allows us to remove code
that's duplicated for each channel type already.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Introduces a new method of defining channels available from the display,
common to all channel types, allowing for more flexibility in available
channel types/counts, and reducing the amount of boiler-plate required.
This will be required to support Volta.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Engines are initialised on an as-needed basis, so this results in the
same behaviour, whilst allowing us to simplify things a bit.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
We should be reading registers to determine which subunits are really
present on a given board, and this needs to be done after DEVINIT.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Likely a rebase bug. Should have no impact in default configuration due
to using per-instance setting by default.
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
In preparation to enabling -Wvla, remove VLA. In this particular
case directly use macro NVKM_MSGQUEUE_CMDLINE_SIZE instead of local
variable cmdline_size. Also, remove cmdline_size as it is not
actually useful anymore.
The use of stack Variable Length Arrays needs to be avoided, as they
can be a vector for stack exhaustion, which can be both a runtime bug
or a security flaw. Also, in general, as code evolves it is easy to
lose track of how big a VLA can get. Thus, we can end up having runtime
failures that are hard to debug.
Also, fixed as part of the directive to remove all VLAs from
the kernel: https://lkml.org/lkml/2018/3/7/621
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Reviewed-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
gcc points out a buffer that is clearly too small to be used
in a meaningful way, as the 'sizeof(*args) + argc > sizeof(stack)'
will always fail:
In function 'memcpy',
inlined from 'nvif_vmm_map' at drivers/gpu/drm/nouveau/nvif/vmm.c:55:2:
include/linux/string.h:353:9: error: '__builtin_memcpy' offset 40 is out of the bounds [0, 16] of object 'stack' with type 'u8[16]' {aka 'unsigned char[16]'} [-Werror=array-bounds]
return __builtin_memcpy(p, q, size);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/gpu/drm/nouveau/nvif/vmm.c: In function 'nvif_vmm_map':
drivers/gpu/drm/nouveau/nvif/vmm.c:40:5: note: 'stack' declared here
This makes the buffer large enough so it should serve the purpose
that the author presumably had in mind. Alternatively we could
just get rid of it completely and simplify the code at the cost
of always doing the kmalloc (as we do in the current version).
Fixes: 920d2b5ef2 ("drm/nouveau/mmu: define user interfaces to mmu vmm opertaions")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
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Merge drm-fixes-for-v4.17-rc6-urgent into drm-next
Need to backmerge some nouveau fixes to reduce
the nouveau -next conflicts a lot.
Signed-off-by: Dave Airlie <airlied@redhat.com>
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Backmerge tag 'v4.16-rc7' into drm-next
Linux 4.16-rc7
This was requested by Daniel, and things were getting
a bit hard to reconcile, most of the conflicts were
trivial though.
It's better to use list_entry instead of list_{next/prev}_entry
as it makes the code more clear to read.
This patch replace list_entry with list_{next/prev}_entry.
Signed-off-by: Arushi Singhal <arushisinghal19971997@gmail.com>
Acked-by: Ben Skeggs <bskeggs@redhat.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/1522000893-5331-3-git-send-email-arushisinghal19971997@gmail.com
Unbinding nouveau on a dual GPU MacBook Pro oopses because we iterate
over the bl_connectors list in nouveau_backlight_exit() but skipped
initializing it in nouveau_backlight_init(). Stacktrace for posterity:
BUG: unable to handle kernel NULL pointer dereference at 0000000000000010
IP: nouveau_backlight_exit+0x2b/0x70 [nouveau]
nouveau_display_destroy+0x29/0x80 [nouveau]
nouveau_drm_unload+0x65/0xe0 [nouveau]
drm_dev_unregister+0x3c/0xe0 [drm]
drm_put_dev+0x2e/0x60 [drm]
nouveau_drm_device_remove+0x47/0x70 [nouveau]
pci_device_remove+0x36/0xb0
device_release_driver_internal+0x157/0x220
driver_detach+0x39/0x70
bus_remove_driver+0x51/0xd0
pci_unregister_driver+0x2a/0xa0
nouveau_drm_exit+0x15/0xfb0 [nouveau]
SyS_delete_module+0x18c/0x290
system_call_fast_compare_end+0xc/0x6f
Fixes: b53ac1ee12 ("drm/nouveau/bl: Do not register interface if Apple GMUX detected")
Cc: stable@vger.kernel.org # v4.10+
Cc: Pierre Moreau <pierre.morrow@free.fr>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Commit 7110c89bb8852ff8b0f88ce05b332b3fe22bd11e ("mmu: swap out round
for ALIGN") replaced two calls to round/rounddown with ALIGN/ALIGN_DOWN,
but erroneously applied ALIGN_DOWN to a different variable (addr) and left
intended variable (tail) not rounded/ALIGNed.
As a result screen corruption, X lockups are observable. An example of kernel
log of affected system with NV98 card where it was bisected:
nouveau 0000:01:00.0: gr: TRAP_M2MF 00000002 [IN]
nouveau 0000:01:00.0: gr: TRAP_M2MF 00320951 400007c0 00000000 04000000
nouveau 0000:01:00.0: gr: 00200000 [] ch 1 [000fbbe000 DRM] subc 4 class 5039
mthd 0100 data 00000000
nouveau 0000:01:00.0: fb: trapped read at 0040000000 on channel 1
[0fbbe000 DRM]
engine 00 [PGRAPH] client 03 [DISPATCH] subclient 04 [M2M_IN] reason 00000006
[NULL_DMAOBJ]
Fixes bug 105173 ("[MCP79][Regression] Unhandled NULL pointer dereference in
nvkm_object_unmap since kernel 4.15")
https://bugs.freedesktop.org/show_bug.cgi?id=105173
Fixes: 7110c89bb885 ("mmu: swap out round for ALIGN ")
Tested-by: Pierre Moreau <pierre.morrow@free.fr>
Reviewed-by: Pierre Moreau <pierre.morrow@free.fr>
Signed-off-by: Maris Nartiss <maris.nartiss@gmail.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Cc: stable@vger.kernel.org # v4.15+
Instead of calculating the size in bytes just to recalculate the number
of pages from it pass the BO directly to the function.
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Roger He <Hongbo.He@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Commit 5addcf0a5f ("nouveau: add runtime PM support (v0.9)") prevents
runtime suspend of the GPU if its integrated HDA controller is not bound
to a driver. The rationale appears to be that probing the HDA fails if
the GPU is in D3cold.
However we now use a device link to ensure that the GPU is runtime
resumed while the HDA controller is probed, rendering this safety
measure obsolete. Remove it.
Cc: Dave Airlie <airlied@redhat.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Takashi Iwai <tiwai@suse.de>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Peter Wu <peter@lekensteyn.nl>
Tested-by: Denis Lisov <dennis.lissov@gmail.com> # Nvidia Optimus
Tested-by: Peter Wu <peter@lekensteyn.nl> # Nvidia Optimus
Tested-by: Lukas Wunner <lukas@wunner.de> # MacBook Pro
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Link: https://patchwork.freedesktop.org/patch/msgid/77e0ab74f3377ea9b6acf8fab624acfb4f7dbeca.1520068884.git.lukas@wunner.de
Back in 2013, runtime PM for GPUs with integrated HDA controller was
introduced with commits 0d69704ae3 ("gpu/vga_switcheroo: add driver
control power feature. (v3)") and 246efa4a07 ("snd/hda: add runtime
suspend/resume on optimus support (v4)").
Briefly, the idea was that the HDA controller is forced on and off in
unison with the GPU.
The original code is mostly still in place even though it was never a
100% perfect solution: E.g. on access to the HDA controller, the GPU
is powered up via vga_switcheroo_runtime_resume_hdmi_audio() but there
are no provisions to keep it resumed until access to the HDA controller
has ceased: The GPU autosuspends after 5 seconds, rendering the HDA
controller inaccessible.
Additionally, a kludge is required when hda_intel.c probes: It has to
check whether the GPU is powered down (check_hdmi_disabled()) and defer
probing if so.
However in the meantime (in v4.10) the driver core has gained a feature
called device links which promises to solve such issues in a clean way:
It allows us to declare a dependency from the HDA controller (consumer)
to the GPU (supplier). The PM core then automagically ensures that the
GPU is runtime resumed as long as the HDA controller's ->probe hook is
executed and whenever the HDA controller is accessed.
By default, the HDA controller has a dependency on its parent, a PCIe
Root Port. Adding a device link creates another dependency on its
sibling:
PCIe Root Port
^ ^
| |
| |
HDA ===> GPU
The device link is not only used for runtime PM, it also guarantees that
on system sleep, the HDA controller suspends before the GPU and resumes
after the GPU, and on system shutdown the HDA controller's ->shutdown
hook is executed before the one of the GPU. It is a complete solution.
Using this functionality is as simple as calling device_link_add(),
which results in a dmesg entry like this:
pci 0000:01:00.1: Linked as a consumer to 0000:01:00.0
The code for the GPU-governed audio power management can thus be removed
(except where it's still needed for legacy manual power control).
The device link is added in a PCI quirk rather than in hda_intel.c.
It is therefore legal for the GPU to runtime suspend to D3cold even if
the HDA controller is not bound to a driver or if CONFIG_SND_HDA_INTEL
is not enabled, for accesses to the HDA controller will cause the GPU to
wake up regardless if they're occurring outside of hda_intel.c (think
config space readout via sysfs).
Contrary to the previous implementation, the HDA controller's power
state is now self-governed, rather than GPU-governed, whereas the GPU's
power state is no longer fully self-governed. (The HDA controller needs
to runtime suspend before the GPU can.)
It is thus crucial that runtime PM is always activated on the HDA
controller even if CONFIG_SND_HDA_POWER_SAVE_DEFAULT is set to 0 (which
is the default), lest the GPU stays awake. This is achieved by setting
the auto_runtime_pm flag on every codec and the AZX_DCAPS_PM_RUNTIME
flag on the HDA controller.
A side effect is that power consumption might be reduced if the GPU is
in use but the HDA controller is not, because the HDA controller is now
allowed to go to D3hot. Before, it was forced to stay in D0 as long as
the GPU was in use. (There is no reduction in power consumption on my
Nvidia GK107, but there might be on other chips.)
The code paths for legacy manual power control are adjusted such that
runtime PM is disabled during power off, thereby preventing the PM core
from resuming the HDA controller.
Note that the device link is not only added on vga_switcheroo capable
systems, but for *any* GPU with integrated HDA controller. The idea is
that the HDA controller streams audio via connectors located on the GPU,
so the GPU needs to be on for the HDA controller to do anything useful.
This commit implicitly fixes an unbalanced runtime PM ref upon unbind of
hda_intel.c: On ->probe, a runtime PM ref was previously released under
the condition "azx_has_pm_runtime(chip) || hda->use_vga_switcheroo", but
on ->remove a runtime PM ref was only acquired under the first of those
conditions. Thus, binding and unbinding the driver twice on a
vga_switcheroo capable system caused the runtime PM refcount to drop
below zero. The issue is resolved because the AZX_DCAPS_PM_RUNTIME flag
is now always set if use_vga_switcheroo is true.
For more information on device links please refer to:
https://www.kernel.org/doc/html/latest/driver-api/device_link.html
Documentation/driver-api/device_link.rst
Cc: Dave Airlie <airlied@redhat.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Takashi Iwai <tiwai@suse.de>
Reviewed-by: Peter Wu <peter@lekensteyn.nl>
Tested-by: Kai Heng Feng <kai.heng.feng@canonical.com> # AMD PowerXpress
Tested-by: Mike Lothian <mike@fireburn.co.uk> # AMD PowerXpress
Tested-by: Denis Lisov <dennis.lissov@gmail.com> # Nvidia Optimus
Tested-by: Peter Wu <peter@lekensteyn.nl> # Nvidia Optimus
Tested-by: Lukas Wunner <lukas@wunner.de> # MacBook Pro
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Link: https://patchwork.freedesktop.org/patch/msgid/51bd38360ff502a8c42b1ebf4405ee1d3f27118d.1520068884.git.lukas@wunner.de
Replace the ad-hoc iturbt_709 property with the new standard
COLOR_ENCODING property. Compiles, but not tested.
v2: Fix typos (Ilia)
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: nouveau@lists.freedesktop.org
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Ilia Mirkin <imirkin@alum.mit.edu>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180220134816.15229-1-ville.syrjala@linux.intel.com
Reviewed-by: Ilia Mirkin <imirkin@alum.mit.edu>
Acked-by: Ben Skeggs <bskeggs@redhat.com> #irc
Never used as parameter, the only driver actually using this is nouveau
and there it is initialized after the BO is initialized.
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Only used by the AGP backend and there it can be easily accessed using
ttm->bdev->glob.
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Nouveau only exposes support for XBGR2101010. Prior to the atomic
conversion, drm would pass in the wrong format in the framebuffer, but
it was always ignored -- both userspace (xf86-video-nouveau) and the
kernel driver agreed on the layout, so the fact that the format was
wrong didn't matter.
With the atomic conversion, nouveau all of a sudden started caring about
the exact format, and so the previously-working code in
xf86-video-nouveau no longer functioned since the (internally-assigned)
format from the addfb ioctl was wrong.
This change adds infrastructure to allow a drm driver to specify that it
prefers the XBGR format variant for the addfb ioctl, and makes nouveau's
nv50 display driver set it. (Prior gens had no support for 30bpp at all.)
Signed-off-by: Ilia Mirkin <imirkin@alum.mit.edu>
Cc: stable@vger.kernel.org # v4.10+
Acked-by: Ben Skeggs <bskeggs@redhat.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20180203191123.31507-1-imirkin@alum.mit.edu
drivers, a memory leak on non-blocking commits, a crash on color-eviction.
The is also meson and edid fixes, plus a fix for a doc warning.
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Merge tag 'drm-misc-fixes-2018-02-21' of git://anongit.freedesktop.org/drm/drm-misc into drm-fixes
Fixes for 4.16. I contains fixes for deadlock on runtime suspend on few
drivers, a memory leak on non-blocking commits, a crash on color-eviction.
The is also meson and edid fixes, plus a fix for a doc warning.
* tag 'drm-misc-fixes-2018-02-21' of git://anongit.freedesktop.org/drm/drm-misc:
drm/tve200: fix kernel-doc documentation comment include
drm/meson: fix vsync buffer update
drm: Handle unexpected holes in color-eviction
drm/edid: Add 6 bpc quirk for CPT panel in Asus UX303LA
drm/amdgpu: Fix deadlock on runtime suspend
drm/radeon: Fix deadlock on runtime suspend
drm/nouveau: Fix deadlock on runtime suspend
drm: Allow determining if current task is output poll worker
workqueue: Allow retrieval of current task's work struct
drm/atomic: Fix memleak on ERESTARTSYS during non-blocking commits
nouveau's ->runtime_suspend hook calls drm_kms_helper_poll_disable(),
which waits for the output poll worker to finish if it's running.
The output poll worker meanwhile calls pm_runtime_get_sync() in
nouveau_connector_detect() which waits for the ongoing suspend to finish,
causing a deadlock.
Fix by not acquiring a runtime PM ref if nouveau_connector_detect() is
called in the output poll worker's context. This is safe because
the poll worker is only enabled while runtime active and we know that
->runtime_suspend waits for it to finish.
Other contexts calling nouveau_connector_detect() do require a runtime
PM ref, these comprise:
status_store() drm sysfs interface
->fill_modes drm callback
drm_fb_helper_probe_connector_modes()
drm_mode_getconnector()
nouveau_connector_hotplug()
nouveau_display_hpd_work()
nv17_tv_set_property()
Stack trace for posterity:
INFO: task kworker/0:1:58 blocked for more than 120 seconds.
Workqueue: events output_poll_execute [drm_kms_helper]
Call Trace:
schedule+0x28/0x80
rpm_resume+0x107/0x6e0
__pm_runtime_resume+0x47/0x70
nouveau_connector_detect+0x7e/0x4a0 [nouveau]
nouveau_connector_detect_lvds+0x132/0x180 [nouveau]
drm_helper_probe_detect_ctx+0x85/0xd0 [drm_kms_helper]
output_poll_execute+0x11e/0x1c0 [drm_kms_helper]
process_one_work+0x184/0x380
worker_thread+0x2e/0x390
INFO: task kworker/0:2:252 blocked for more than 120 seconds.
Workqueue: pm pm_runtime_work
Call Trace:
schedule+0x28/0x80
schedule_timeout+0x1e3/0x370
wait_for_completion+0x123/0x190
flush_work+0x142/0x1c0
nouveau_pmops_runtime_suspend+0x7e/0xd0 [nouveau]
pci_pm_runtime_suspend+0x5c/0x180
vga_switcheroo_runtime_suspend+0x1e/0xa0
__rpm_callback+0xc1/0x200
rpm_callback+0x1f/0x70
rpm_suspend+0x13c/0x640
pm_runtime_work+0x6e/0x90
process_one_work+0x184/0x380
worker_thread+0x2e/0x390
Bugzilla: https://bugs.archlinux.org/task/53497
Bugzilla: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=870523
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=70388#c33
Fixes: 5addcf0a5f ("nouveau: add runtime PM support (v0.9)")
Cc: stable@vger.kernel.org # v3.12+: 27d4ee0307: workqueue: Allow retrieval of current task's work struct
Cc: stable@vger.kernel.org # v3.12+: 25c058ccaf: drm: Allow determining if current task is output poll worker
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Dave Airlie <airlied@redhat.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Link: https://patchwork.freedesktop.org/patch/msgid/b7d2cbb609a80f59ccabfdf479b9d5907c603ea1.1518338789.git.lukas@wunner.de
