bochs_pci_probe() allocates the DRM device with devm_drm_dev_alloc(),
which registers a devres action to drop the initial DRM device reference
on driver detach or probe failure.
The error path currently calls drm_dev_put() manually. If probe then
returns an error, devres will run the registered release action and put
the same device again, after the first put may already have released it.
Return the probe error directly and let devres own the final put.
Signed-off-by: Myeonghun Pak <mhun512@gmail.com>
Fixes: 04826f5886 ("drm/bochs: Allocate DRM device in struct bochs_device")
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patch.msgid.link/20260424123506.32275-1-mhun512@gmail.com
Use a vblank timer to simulate the vblank interrupt. The DRM vblank
helpers provide an implementation on top of Linux' hrtimer. Bochs
enables and disables the timer as part of the CRTC. The atomic_flush
callback sets up the event. Like vblank interrupts, the vblank timer
fires at the rate of the display refresh.
Most userspace limits its page flip rate according to the DRM vblank
event. Bochs' virtual hardware does not provide vblank interrupts, so
DRM sends each event ASAP. With the fast access time of virtual display
memory, the event rate is much higher than the display mode's refresh
rate; creating the next page flip almost immediately. This leads to
excessive CPU overhead from even small display updates, such as moving
the mouse pointer.
This problem affects bochs and all other virtual displays. See [1] for
a discussion in the context of hypervdrm.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://lore.kernel.org/dri-devel/SN6PR02MB415702B00D6D52B0EE962C98D46CA@SN6PR02MB4157.namprd02.prod.outlook.com/ # [1]
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Link: https://lore.kernel.org/r/20251008093931.19138-1-tzimmermann@suse.de
The DRM subsystem has a set of preferred, prefixed logging functions
(drm_info, drm_warn, drm_err) which improve debuggability by including
the driver and function name in the log output.
As part of the ongoing effort to modernize logging calls,
convert a dev_err() call in the bochs hardware initialization
function to its drm_err() equivalent.
This work was suggested by the DRM TODO list.
Signed-off-by: Leander Kieweg <kieweg.leander@gmail.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://lore.kernel.org/r/20250818113530.187440-1-kieweg.leander@gmail.com
Pull drm updates from Dave Airlie:
"There's a lot of rework, the panic helper support is being added to
more drivers, v3d gets support for HW superpages, scheduler
documentation, drm client and video aperture reworks, some new
MAINTAINERS added, amdgpu has the usual lots of IP refactors, Intel
has some Pantherlake enablement and xe is getting some SRIOV bits, but
just lots of stuff everywhere.
core:
- split DSC helpers from DP helpers
- clang build fixes for drm/mm test
- drop simple pipeline support for gem vram
- document submission error signaling
- move drm_rect to drm core module from kms helper
- add default client setup to most drivers
- move to video aperture helpers instead of drm ones
tests:
- new framebuffer tests
ttm:
- remove swapped and pinned BOs from TTM lru
panic:
- fix uninit spinlock
- add ABGR2101010 support
bridge:
- add TI TDP158 support
- use standard PM OPS
dma-fence:
- use read_trylock instead of read_lock to help lockdep
scheduler:
- add errno to sched start to report different errors
- add locking to drm_sched_entity_modify_sched
- improve documentation
xe:
- add drm_line_printer
- lots of refactoring
- Enable Xe2 + PES disaggregation
- add new ARL PCI ID
- SRIOV development work
- fix exec unnecessary implicit fence
- define and parse OA sync props
- forcewake refactoring
i915:
- Enable BMG/LNL ultra joiner
- Enable 10bpx + CCS scanout on ICL+, fp16/CCS on TGL+
- use DSB for plane/color mgmt
- Arrow lake PCI IDs
- lots of i915/xe display refactoring
- enable PXP GuC autoteardown
- Pantherlake (PTL) Xe3 LPD display enablement
- Allow fastset HDR infoframe changes
- write DP source OUI for non-eDP sinks
- share PCI IDs between i915 and xe
amdgpu:
- SDMA queue reset support
- SMU 13.0.6, JPEG 4.0.3 updates
- Initial runtime repartitioning support
- rework IP structs for multiple IP instances
- Fetch EDID from _DDC if available
- SMU13 zero rpm user control
- lots of fixes/cleanups
amdkfd:
- Increase event FIFO size
- add topology cap flag for per queue reset
msm:
- DPU:
- SA8775P support
- (disabled by default) MSM8917, MSM8937, MSM8953 and MSM8996 support
- Enable large framebuffer support
- Drop MSM8998 and SDM845
- DP:
- SA8775P support
- GPU:
- a7xx preemption support
- Adreno A663 support
ast:
- warn about unsupported TX chips
ivpu:
- add coredump
- add pantherlake support
rockchip:
- 4K@60Hz display enablement
- generate pll programming tables
panthor:
- add timestamp query API
- add realtime group priority
- add fdinfo support
etnaviv:
- improve handling of DMA address limits
- improve GPU hangcheck
exynos:
- Decon Exynos7870 support
mediatek:
- add OF graph support
omap:
- locking fixes
bochs:
- convert to gem/shmem from simpledrm
v3d:
- support big/super pages
- add gemfs
vc4:
- BCM2712 support refactoring
- add YUV444 format support
udmabuf:
- folio related fixes
nouveau:
- add panic support on nv50+"
* tag 'drm-next-2024-11-21' of https://gitlab.freedesktop.org/drm/kernel: (1583 commits)
drm/xe/guc: Fix dereference before NULL check
drm/amd: Fix initialization mistake for NBIO 7.7.0
Revert "drm/amd/display: parse umc_info or vram_info based on ASIC"
drm/amd/display: Fix failure to read vram info due to static BP_RESULT
drm/amdgpu: enable GTT fallback handling for dGPUs only
drm/amd/amdgpu: limit single process inside MES
drm/fourcc: add AMD_FMT_MOD_TILE_GFX9_4K_D_X
drm/amdgpu/mes12: correct kiq unmap latency
drm/amdgpu: Support vcn and jpeg error info parsing
drm/amd : Update MES API header file for v11 & v12
drm/amd/amdkfd: add/remove kfd queues on start/stop KFD scheduling
drm/amdkfd: change kfd process kref count at creation
drm/amdgpu: Cleanup shift coding style
drm/amd/amdgpu: Increase MES log buffer to dump mes scratch data
drm/amdgpu: Implement virt req_ras_err_count
drm/amdgpu: VF Query RAS Caps from Host if supported
drm/amdgpu: Add msg handlers for SRIOV RAS Telemetry
drm/amdgpu: Update SRIOV Exchange Headers for RAS Telemetry Support
drm/amd/display: 3.2.309
drm/amd/display: Adjust VSDB parser for replay feature
...
In a future patch HAS_IOPORT=n will disable inb()/outb() and friends at
compile time. We thus need to add HAS_IOPORT as dependency for those
drivers using them. In the bochs driver there is optional MMIO support
detected at runtime, warn if this isn't taken when HAS_IOPORT is not
defined.
There is also a direct and hard coded use in cirrus.c which according to
the comment is only necessary during resume. Let's just skip this as
for example s390 which doesn't have I/O port support also doesen't
support suspend/resume.
Co-developed-by: Arnd Bergmann <arnd@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@kernel.org>
Acked-by: Lucas De Marchi <lucas.demarchi@intel.com> # xe
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Call drm_client_setup() to run the kernel's default client setup
for DRM. Set fbdev_probe in struct drm_driver, so that the client
setup can start the common fbdev client.
The bochs driver specifies a preferred color mode of 32. As this
is the default if no format has been given, leave it out entirely.
v5:
- select DRM_CLIENT_SELECTION
v4:
- rebase on top of GEM-SHMEM
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240924071734.98201-52-tzimmermann@suse.de
Opt for devm_ioremap_wc() over devm_ioremap() when mapping the framebuffer.
Using devm_ioremap() results in the VA being mapped with PAT=UC-, which
considerably slows down drm_fb_memcpy(). In contrast, devm_ioremap_wc()
maps the VA with PAT set to WC, leading to better performance on platforms
where access to UC memory is much slower than WC memory.
Here's the performance data measured in a guest on the physical machine
"Sapphire Rapids XCC".
With host KVM honors guest PAT memory types, the effective memory type
for this framebuffer range is
- WC when devm_ioremap_wc() is used
- UC- when devm_ioremap() is used.
The data presented is an average from 10 execution runs.
Cycles: Avg cycles of executed bochs_primary_plane_helper_atomic_update()
from VM boot to GDM show up
Cnt: Avg cnt of executed bochs_primary_plane_helper_atomic_update()
from VM boot to GDM show up
T: Avg time of each bochs_primary_plane_helper_atomic_update().
-------------------------------------------------
| | devm_ioremap() | devm_ioremap_wc() |
|------------|----------------|-------------------|
| Cycles | 211.545M | 0.157M |
|------------|----------------|-------------------|
| Cnt | 142 | 1917 |
|------------|----------------|-------------------|
| T | 0.1748s | 0.0004s |
-------------------------------------------------
Note:
Following the rebase to [3], the previously reported GDM failure on the
VGA device [1] can no longer be reproduced, thanks to the memory management
improvements made in [2]. Despite this, I have proceeded to submit this
patch because of the noticeable performance improvements it provides.
Reported-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Closes: https://lore.kernel.org/all/87jzfutmfc.fsf@redhat.com/#t
Cc: Sean Christopherson <seanjc@google.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Yan Zhao <yan.y.zhao@intel.com>
Link: https://lore.kernel.org/all/87jzfutmfc.fsf@redhat.com/#t [1]
Link: https://patchwork.freedesktop.org/series/138086 [2]
Link: https://gitlab.freedesktop.org/drm/misc/kernel/-/tree/drm-misc-next [3]
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Tested-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Tested-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20240909131643.28915-1-yan.y.zhao@intel.com
For each mode, test the required memory against the available video
memory. Filters out modes that do not fit into display memory.
Also remove the old test against the 4 MiB limit. It is now obsolete
and did not necessarily produce correct results.
v2:
- fix __udivdi3 linker error (kernel test robot)
- fix vdisplay and hdisplay usage
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240902105546.792625-10-tzimmermann@suse.de
Replace GEM VRAM with GEM SHMEM in bochs. The new memory manager
stores buffer objects in system memory. Makes the driver's memory
management more reliably.
Most of the changes are hidden in external helpers that allocate
buffers. Replacing DRM_GEM_VRAM_DRIVER with DRM_GEM_SHMEM_DRIVER_OPS
swaps these. With GEM VRAM, the video memory was updated directly by
the DRM client. The biggest change within bochs is in atomic_update,
which now updates video memory via memcpy() from the BO in system
memory. Shadow-plane helpers maintaining the pointers to the buffer's
data, so bochs doesn't have to. The update is triggered by each page
flip's call to the framebuffer's dirty helper. The driver supports
damage clipping to minimize memcpy() overhead.
The advantage of GEM SHMEM is that it makes memory management
more reliable. Given DRM's double buffering during page flips, the
minimum amount of video memory is three times the maximum consumption
in some pathological cases. For example, if the maximum size of a GEM
buffer is 1920x1080-32 (i.e., 32-bit FullHD), the buffer size is
8 MiB. Display hardware has to provide at lease 24 MiB to reliably
page flip such configurations. This cannot always be guaranteed and
bochs already contains code to rule out <4 MiB configurations. With
GEM SHMEM, only 8 MiB of video memory are required for the given
example. Unsupported modes can be sorted out easily.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240902105546.792625-9-tzimmermann@suse.de
Remove the simple display pipeline in favor of the regular atomic
helpers in bochs. The simple-pipe helpers are considered deprecated
in DRM.
This effectivly inlines the simple-pipe code for plane and CRTC
support. Instead of a single update helper, there's now a mode-set
helper for the CRTC and an update helper for the plane. The encoder
changes type from NONE ot VIRTUAL.
Removing simple-pipe helpers from bochs will allow for related
cleanups in GEM VRAM helpers.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240902105546.792625-8-tzimmermann@suse.de
Implement a read function for struct drm_edid and read the EDID data
with drm_edit_read_custom(). Update the connector data accordingly.
The EDID data comes from the emulator itself and the connector stores
a copy in its EDID property. The drm_edid field in struct bochs_device
is therefore not required. Remove it.
If qemu provides no EDID data, install default display modes as before.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240902105546.792625-3-tzimmermann@suse.de
Myeonghun PakandThomas Zimmermann
Jani Nikula
Leander KiewegandThomas Zimmermann
Ryosuke YasuokaandJocelyn Falempe
Takashi IwaiandThomas Zimmermann
Maxime Ripard
Linus Torvalds
Niklas SchnelleandArnd Bergmann
Yan ZhaoandThomas Zimmermann