- 28 Oct, 2022 4 commits
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Maxime Ripard authored
In order to support higher HDMI frequencies, users have to set the hdmi_enable_4kp60 parameter in their config.txt file. We were detecting this so far by calling clk_round_rate() on the core clock with the frequency we're supposed to run at when one of those modes is enabled. Whether or not the parameter was enabled could then be inferred by the returned rate since the maximum clock rate reported by the firmware was one of the side effect of setting that parameter. However, the recent clock rework we did changed what clk_round_rate() was returning to always return the minimum allowed, and thus this test wasn't reliable anymore. Let's use the new clk_get_max_rate() function to reliably determine the maximum rate allowed on that clock and fix the 4k@60Hz output. Fixes: e9d6cea2 ("clk: bcm: rpi: Run some clocks at the minimum rate allowed") Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com> Link: https://lore.kernel.org/r/20220815-rpi-fix-4k-60-v5-4-fe9e7ac8b111@cerno.techSigned-off-by: Maxime Ripard <maxime@cerno.tech>
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Maxime Ripard authored
The firmware allows to query for its clocks the operating range of a given clock. We'll need this for some drivers (KMS, in particular) to infer the state of some configuration options, so let's create a function to do so. Acked-by: Stephen Boyd <sboyd@kernel.org> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Acked-by: Florian Fainelli <f.fainelli@gmail.com> Link: https://lore.kernel.org/r/20220815-rpi-fix-4k-60-v5-3-fe9e7ac8b111@cerno.techSigned-off-by: Maxime Ripard <maxime@cerno.tech>
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Maxime Ripard authored
We'll need the clock IDs in more drivers than just the clock driver from now on, so let's move them in the firmware header. Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Acked-by: Stephen Boyd <sboyd@kernel.org> Link: https://lore.kernel.org/r/20220815-rpi-fix-4k-60-v5-2-fe9e7ac8b111@cerno.techSigned-off-by: Maxime Ripard <maxime@cerno.tech>
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Maxime Ripard authored
A significant number of RaspberryPi drivers using the firmware don't have a phandle to it, so end up scanning the device tree to find a node with the firmware compatible. That code is duplicated everywhere, so let's introduce a helper instead. Acked-by: Florian Fainelli <f.fainelli@gmail.com> Link: https://lore.kernel.org/r/20220815-rpi-fix-4k-60-v5-1-fe9e7ac8b111@cerno.techSigned-off-by: Maxime Ripard <maxime@cerno.tech>
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- 27 Oct, 2022 2 commits
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Pin-yen Lin authored
`pm_runtime_get_sync` may return 1 on success. Fix the `if` statement here to make the code less confusing, even though additional calls to `it6505_poweron` doesn't break anything when it's already powered. This was reported by Dan Carpenter <dan.carpenter@oracle.com> in https://lore.kernel.org/all/Y1fMCs6VnxbDcB41@kili/ Fixes: 10517777 ("drm/bridge: it6505: Adapt runtime power management framework") Signed-off-by: Pin-yen Lin <treapking@chromium.org> Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org> Link: https://patchwork.freedesktop.org/patch/msgid/20221027032149.2739912-1-treapking@chromium.org
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Somalapuram Amaranath authored
Change ttm_resource structure from num_pages to size_t size in bytes. v1 -> v2: change PFN_UP(dst_mem->size) to ttm->num_pages v1 -> v2: change bo->resource->size to bo->base.size at some places v1 -> v2: remove the local variable v1 -> v2: cleanup cmp_size_smaller_first() v2 -> v3: adding missing PFN_UP in ttm_bo_vm_fault_reserved Signed-off-by: Somalapuram Amaranath <Amaranath.Somalapuram@amd.com> Link: https://patchwork.freedesktop.org/patch/msgid/20221027091237.983582-1-Amaranath.Somalapuram@amd.comReviewed-by: Christian König <christian.koenig@amd.com> Signed-off-by: Christian König <christian.koenig@amd.com>
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- 26 Oct, 2022 16 commits
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Jani Nikula authored
Convert to drm_kms_dbg/drm_err where possible, and reference the connector using [CONNECTOR:%d:%s]. Pass connectors around a bit more to enable this. Where this is not possible, unify the rest of the debugs to DRM_DEBUG_KMS. Rewrite tile debug logging to one line while at it. v2: - Use [CONNECTOR:%d:%s] throughout (Ville) - Tile debug logging revamp - Pass connector around a bit more Signed-off-by: Jani Nikula <jani.nikula@intel.com> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/e48346bfe09a632d5a5faa55e3c161b196cf21e8.1666614699.git.jani.nikula@intel.com
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Jani Nikula authored
Reference the connector using [CONNECTOR:%d:%s] in existing device based debug logging. Signed-off-by: Jani Nikula <jani.nikula@intel.com> Reviewed-by: Simon Ser <contact@emersion.fr> Link: https://patchwork.freedesktop.org/patch/msgid/5884410682bcbc032de4d3af8562c0b271edaa7f.1666614699.git.jani.nikula@intel.com
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Jani Nikula authored
Conform to device specific logging. v2: Include [CONNECTOR:%d:%s] (Ville) Signed-off-by: Jani Nikula <jani.nikula@intel.com> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/14f3a1e55729c9157aae93fc45320d05cc4cc7bc.1666614699.git.jani.nikula@intel.com
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Jani Nikula authored
The EDID loader is internal to drm, not for drivers. Signed-off-by: Jani Nikula <jani.nikula@intel.com> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/d58a59fede286caa8766e0813f4be492a7200287.1666614699.git.jani.nikula@intel.com
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Jani Nikula authored
There's a lot going on here, but the main thing is switching the firmware EDID loader to use struct drm_edid. Unfortunately, it's difficult to reasonably split to smaller pieces. Convert the EDID loader to struct drm_edid. There's a functional change in validation; it no longer tries to fix errors or filter invalid blocks. It's stricter in this sense. Hopefully this will not be an issue. As a by-product, this change also allows HF-EEODB extended EDIDs to be passed via override/firmware EDID. Signed-off-by: Jani Nikula <jani.nikula@intel.com> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/e64267c28eca483e83c802bc06ddd149bdcdfc66.1666614699.git.jani.nikula@intel.com
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Jani Nikula authored
Follow the usual naming convention by file name. Signed-off-by: Jani Nikula <jani.nikula@intel.com> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/d6714ae737d789764bd2bdb6e7c9a5f56c99eef3.1666614699.git.jani.nikula@intel.com
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Jani Nikula authored
Stop passing around something that's readily available in connector->name. Signed-off-by: Jani Nikula <jani.nikula@intel.com> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/befa53a33f2ea83094027a0e88d155779ad096e1.1666614699.git.jani.nikula@intel.com
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Jani Nikula authored
Having the EDID override debugfs directly update the EDID property is problematic. The update is partial only. The driver has no way of knowing it's been updated. Mode list is not updated. It's an inconsistent state. Detach debugfs EDID override from the property update completely. Only set and reset a separate override EDID copy from debugfs, and have it take effect only at detect (via EDID read). The copy is at connector->edid_override, protected by connector->edid_override_mutex. This also brings override EDID closer to firmware EDID in behaviour. Add validation of the override EDID which we completely lacked. Note that IGT already forces a detect whenever tests update the override EDID. v2: Add locking (Ville) Signed-off-by: Jani Nikula <jani.nikula@intel.com> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/4c875f8e06c4499f498fcf876e1233cbb155ec8a.1666614699.git.jani.nikula@intel.com
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Jani Nikula authored
We've lacked a function for immutable validity check on drm_edid. Add one. Signed-off-by: Jani Nikula <jani.nikula@intel.com> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/f96188f64e9f7f3deff348d08296609353b12316.1666614699.git.jani.nikula@intel.com
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Jani Nikula authored
Split the drm_edid block count helper to a base version that reports the block count indicated by EDID contents, and another on top that limits the block count based on size allocated for the EDID. Signed-off-by: Jani Nikula <jani.nikula@intel.com> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/a7d63878c7fb3dd6f3b987f5257897113797b94f.1666614699.git.jani.nikula@intel.com
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Jani Nikula authored
Follow the naming of both EDID override functions as well as drm_edid_connector_update(). This also matches better what the function does; a combination of EDID property update and add modes. Indeed it should later be converted to call drm_edid_connector_update(). Signed-off-by: Jani Nikula <jani.nikula@intel.com> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/ba12957e0488654e8db010a3ff1534079caec972.1666614699.git.jani.nikula@intel.com
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Jani Nikula authored
Add a function to dump the override EDID in debugfs. This hides the override EDID management better in drm_edid.c. Signed-off-by: Jani Nikula <jani.nikula@intel.com> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/74defa7b595f51e6c1f2eacd9c799d567d29f053.1666614699.git.jani.nikula@intel.com
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Jani Nikula authored
It's useful debugging information to know if and when an override EDID was set or reset. Signed-off-by: Jani Nikula <jani.nikula@intel.com> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/ae352f542b4d69398c0965e33fb2e6e34156cbfb.1666614699.git.jani.nikula@intel.com
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Jani Nikula authored
The connector->override_edid flag is strictly for EDID override debugfs management, and drivers have no business using it. Cc: Alex Deucher <alexander.deucher@amd.com> Cc: Christian König <christian.koenig@amd.com> Cc: Xinhui Pan <Xinhui.Pan@amd.com> Cc: amd-gfx@lists.freedesktop.org Signed-off-by: Jani Nikula <jani.nikula@intel.com> Reviewed-by: Harry Wentland <harry.wentland@amd.com> Acked-by: Alex Deucher <alexdeucher@gmail.com> Link: https://patchwork.freedesktop.org/patch/msgid/c901869ff8a4e3aebc4abec99c7dd7b4c224f6e6.1666614699.git.jani.nikula@intel.com
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Jani Nikula authored
The connector->override_edid flag is strictly for EDID override debugfs management, and drivers have no business using it. The check for override_edid was added in commit 30190629 ("drm/i915: Ignore TMDS clock limit for DP++ when EDID override is set") to facilitate mode list cross-checking against modes in override EDID when the connector in question isn't even connected. The dual mode detect fallback would do VBT based limiting in this case. Instead of override EDID, check for connector forcing in the fallback. v2: Simply use !connector->force (Ville) Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Signed-off-by: Jani Nikula <jani.nikula@intel.com> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/c8b45867cf37134ab40be23e22825ca45adc6041.1666614699.git.jani.nikula@intel.com
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Jani Nikula authored
For normal connector detect, there's really no point in trying dual mode detect if the connector is disconnected. We can simplify the detect sequence by skipping it. Since intel_hdmi_dp_dual_mode_detect() is only called when EDID is present, we can drop the has_edid parameter. The functional effect is speeding up disconnected connector detection ever so slightly, and, combined with firmware EDID, also stop logging about assuming dual mode adaptor. It's a bit subtle, but this will also skip dual mode detect if the connector is force connected and a) there's no EDID of any kind, normal or override/firmware or b) there's EDID but it does not indicate digital. These are corner cases no matter what, and arguably forcing should not be limited by dual mode detect. Cc: Ville Syrjälä <ville.syrjala@linux.intel.com> Signed-off-by: Jani Nikula <jani.nikula@intel.com> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/f8f2a4a147e1c87ba93269a607f71fc29c4b59f6.1666614699.git.jani.nikula@intel.com
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- 25 Oct, 2022 18 commits
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Zack Rusin authored
Fixes a warning about extra docs about a function argument that has been removed a while back: drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c:3888: warning: Excess function parameter 'sync_file' description in 'vmw_execbuf_copy_fence_user' Fixes: a0f90c88 ("drm/vmwgfx: Fix stale file descriptors on failed usercopy") Signed-off-by: Zack Rusin <zackr@vmware.com> Reviewed-by: Martin Krastev <krastevm@vmware.com> Reviewed-by: Maaz Mombasawala <mombasawalam@vmware.com> Link: https://patchwork.freedesktop.org/patch/msgid/20221022040236.616490-18-zack@kde.org
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Zack Rusin authored
It's important to get the initial size of cotables right because otherwise every app needs to start with a synchronous cotable resize. This has an measurable impact on system wide performance but is not relevant for long running single full screen apps for which the cotable resizes will happen early in the lifecycle and will continue running just fine. To eliminate the initial cotable resizes match the initial sizes to what the userspace expects. The actual result of the patch is simply setting the initial size of two of the cotables to a size that will align them to two pages instead of one. For a piglit run, before: name | total | per frame | per sec vmw_cotable_resize | 1405 | 0.12 | 1.58 vmw_execbuf_ioctl | 290805 | 25.43 | 326.05 After: name | total | per frame | per sec vmw_cotable_resize | 4 | 0.00 | 0.00 vmw_execbuf_ioctl | 281673 | 25.10 | 274.68 Signed-off-by: Zack Rusin <zackr@vmware.com> Reviewed-by: Michael Banack <banackm@vmware.com> Link: https://patchwork.freedesktop.org/patch/msgid/20221022040236.616490-17-zack@kde.org
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Zack Rusin authored
There's been a lot of cotable resizes on startup which we can track by adding a mks stat to measure both the invocation count and time spent doing cotable resizes. This is only used if kernel is configured with CONFIG_DRM_VMWGFX_MKSSTATS The stats are collected on the host size inside the vmware-stats.log file. Signed-off-by: Zack Rusin <zackr@vmware.com> Reviewed-by: Michael Banack <banackm@vmware.com> Reviewed-by: Martin Krastev <krastevm@vmware.com> Reviewed-by: Maaz Mombasawala <mombasawalam@vmware.com> Link: https://patchwork.freedesktop.org/patch/msgid/20221022040236.616490-16-zack@kde.org
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Zack Rusin authored
The explicit vblank handling was never finished. The driver never had the full implementation of vblank and what was there is emulated by DRM when the driver doesn't pretend to be implementing it itself. Let DRM handle the vblank emulation and stop pretending the driver is doing anything special with vblank. In the future it would make sense to implement helpers for full vblank handling because vkms and amdgpu_vkms already have that code. Exporting it to common helpers and having all three drivers share it would make sense (that would be largely just to allow more of igt to run). Signed-off-by: Zack Rusin <zackr@vmware.com> Reviewed-by: Maaz Mombasawala <mombasawalam@vmware.com> Reviewed-by: Martin Krastev <krastevm@vmware.com> Reviewed-by: Michael Banack <banackm@vmware.com> Link: https://patchwork.freedesktop.org/patch/msgid/20221022040236.616490-15-zack@kde.org
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Zack Rusin authored
Instead of using vmwgfx specific framebuffer implementation use the drm fb helpers. There's no change in functionality, the only difference is a reduction in the amount of code inside the vmwgfx module. drm fb helpers do not deal correctly with changes in crtc preferred mode at runtime, but the old fb code wasn't dealing with it either. Same situation applies to high-res fb consoles - the old code was limited to 1176x885 because it was checking for legacy/deprecated memory limites, the drm fb helpers are limited to the initial resolution set on fb due to first problem (drm fb helpers being unable to handle hotplug crtc preferred mode changes). This also removes the kernel config for disabling fb support which hasn't been used or supported in a very long time. Signed-off-by: Zack Rusin <zackr@vmware.com> Reviewed-by: Maaz Mombasawala <mombasawalam@vmware.com> Reviewed-by: Martin Krastev <krastevm@vmware.com> Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de> Link: https://patchwork.freedesktop.org/patch/msgid/20221022040236.616490-14-zack@kde.org
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Zack Rusin authored
Dumb buffers allow a very limited set of formats. Basically everything apart from 1, 2 and 4 is expected to return an error. Make vmwgfx follow those guidelines. This fixes igt's dumb_buffer invalid_bpp test on vmwgfx. Signed-off-by: Zack Rusin <zackr@vmware.com> Reviewed-by: Martin Krastev <krastevm@vmware.com> Reviewed-by: Maaz Mombasawala <mombasawalam@vmware.com> Link: https://patchwork.freedesktop.org/patch/msgid/20221022040236.616490-13-zack@kde.org
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Maaz Mombasawala authored
The vmwgfx driver has migrated from using the hashtable in vmwgfx_hashtab to the linux/hashtable implementation. Remove the vmwgfx_hashtab from the driver. Signed-off-by: Maaz Mombasawala <mombasawalam@vmware.com> Reviewed-by: Martin Krastev <krastevm@vmware.com> Reviewed-by: Zack Rusin <zackr@vmware.com> Signed-off-by: Zack Rusin <zackr@vmware.com> Link: https://patchwork.freedesktop.org/patch/msgid/20221022040236.616490-12-zack@kde.org
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Maaz Mombasawala authored
This is part of an effort to move from the vmwgfx_open_hash hashtable to linux/hashtable implementation. Refactor the ref_hash hashtable, used for fast lookup of reference objects associated with a ttm file. This also exposed a problem related to inconsistently using 32-bit and 64-bit keys with this hashtable. The hash function used changes depending on the size of the type, and results are not consistent across numbers, for example, hash_32(329) = 329, but hash_long(329) = 328. This would cause the lookup to fail for objects already in the hashtable, since keys of different sizes were being passed during adding and lookup. This was not an issue before because vmwgfx_open_hash always used hash_long. Fix this by always using 64-bit keys for this hashtable, which means that hash_long is always used. Signed-off-by: Maaz Mombasawala <mombasawalam@vmware.com> Reviewed-by: Zack Rusin <zackr@vmware.com> Signed-off-by: Zack Rusin <zackr@vmware.com> Link: https://patchwork.freedesktop.org/patch/msgid/20221022040236.616490-11-zack@kde.org
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Michael Banack authored
Extend the cursor diffing support to support the command-path. Signed-off-by: Michael Banack <banackm@vmware.com> Signed-off-by: Zack Rusin <zackr@vmware.com> Link: https://patchwork.freedesktop.org/patch/msgid/20221022040236.616490-10-zack@kde.org
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Michael Banack authored
Add support for cursor surfaces when using mob cursors. Signed-off-by: Michael Banack <banackm@vmware.com> Signed-off-by: Zack Rusin <zackr@vmware.com> Link: https://patchwork.freedesktop.org/patch/msgid/20221022040236.616490-9-zack@kde.org
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Michael Banack authored
Avoid making the SVGA device do extra work if the new cursor image matches the old one. Signed-off-by: Michael Banack <banackm@vmware.com> Signed-off-by: Zack Rusin <zackr@vmware.com> Link: https://patchwork.freedesktop.org/patch/msgid/20221022040236.616490-8-zack@kde.org
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Michael Banack authored
Clean up the cursor mob path by moving ownership of the mobs into the plane_state, and just leaving a cache of unused mobs in the plane itself. Signed-off-by: Michael Banack <banackm@vmware.com> Signed-off-by: Zack Rusin <zackr@vmware.com> Link: https://patchwork.freedesktop.org/patch/msgid/20221022040236.616490-7-zack@kde.org
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Maaz Mombasawala authored
Vmwgfx's hashtab implementation needs to be replaced with linux/hashtable to reduce maintenence burden. As part of this effort, refactor the res_ht hashtable used for resource validation during execbuf execution to use linux/hashtable implementation. This also refactors vmw_validation_context to use vmw_sw_context as the container for the hashtable, whereas before it used a vmwgfx_open_hash directly. This makes vmw_validation_context less generic, but there is no functional change since res_ht is the only instance where validation context used a hashtable in vmwgfx driver. Signed-off-by: Maaz Mombasawala <mombasawalam@vmware.com> Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> Signed-off-by: Zack Rusin <zackr@vmware.com> Link: https://patchwork.freedesktop.org/patch/msgid/20221022040236.616490-6-zack@kde.org
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Maaz Mombasawala authored
The object_hash hashtable for ttm objects is not being used. Remove it and perform refactoring in ttm_object init function. Signed-off-by: Maaz Mombasawala <mombasawalam@vmware.com> Reviewed-by: Zack Rusin <zackr@vmware.com> Reviewed-by: Martin Krastev <krastevm@vmware.com> Signed-off-by: Zack Rusin <zackr@vmware.com> Link: https://patchwork.freedesktop.org/patch/msgid/20221022040236.616490-5-zack@kde.org
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Maaz Mombasawala authored
Vmwgfx's hashtab implementation needs to be replaced with linux/hashtable to reduce maintenance burden. Refactor cmdbuf resource manager to use linux/hashtable.h implementation as part of this effort. Signed-off-by: Maaz Mombasawala <mombasawalam@vmware.com> Reviewed-by: Zack Rusin <zackr@vmware.com> Reviewed-by: Martin Krastev <krastevm@vmware.com> Signed-off-by: Zack Rusin <zackr@vmware.com> Link: https://patchwork.freedesktop.org/patch/msgid/20221022040236.616490-4-zack@kde.org
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Martin Krastev authored
Function vmw_mksstat_add_ioctl allocates three big arrays on stack. That triggers frame-size [-Wframe-larger-than=] warning. Refactor that function to use kmalloc_array instead. v2: Initialize page to null to avoid possible uninitialized use of it, spotted by the kernel test robot <lkp@intel.com> Signed-off-by: Martin Krastev <krastevm@vmware.com> Reviewed-by: Zack Rusin <zackr@vmware.com> Reviewed-by: Maaz Mombasawala <mombasawalam@vmware.com> Signed-off-by: Zack Rusin <zackr@vmware.com> Link: https://patchwork.freedesktop.org/patch/msgid/20221022040236.616490-3-zack@kde.org
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Zack Rusin authored
Driver id registers are a new mechanism in the svga device to hint to the device which driver is running. This should not change device behavior in any way, but might be convenient to work-around specific bugs in guest drivers. Signed-off-by: Zack Rusin <zackr@vmware.com> Reviewed-by: Martin Krastev <krastevm@vmware.com> Reviewed-by: Maaz Mombasawala <mombasawalam@vmware.com> Link: https://patchwork.freedesktop.org/patch/msgid/20221022040236.616490-2-zack@kde.org
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Luben Tuikov authored
The currently default Round-Robin GPU scheduling can result in starvation of entities which have a large number of jobs, over entities which have a very small number of jobs (single digit). This can be illustrated in the following diagram, where jobs are alphabetized to show their chronological order of arrival, where job A is the oldest, B is the second oldest, and so on, to J, the most recent job to arrive. ---> entities j | H-F-----A--E--I-- o | --G-----B-----J-- b | --------C-------- s\/ --------D-------- WLOG, assuming all jobs are "ready", then a R-R scheduling will execute them in the following order (a slice off of the top of the entities' list), H, F, A, E, I, G, B, J, C, D. However, to mitigate job starvation, we'd rather execute C and D before E, and so on, given, of course, that they're all ready to be executed. So, if all jobs are ready at this instant, the order of execution for this and the next 9 instances of picking the next job to execute, should really be, A, B, C, D, E, F, G, H, I, J, which is their chronological order. The only reason for this order to be broken, is if an older job is not yet ready, but a younger job is ready, at an instant of picking a new job to execute. For instance if job C wasn't ready at time 2, but job D was ready, then we'd pick job D, like this: 0 +1 +2 ... A, B, D, ... And from then on, C would be preferred before all other jobs, if it is ready at the time when a new job for execution is picked. So, if C became ready two steps later, the execution order would look like this: ......0 +1 +2 ... A, B, D, E, C, F, G, H, I, J This is what the FIFO GPU scheduling algorithm achieves. It uses a Red-Black tree to keep jobs sorted in chronological order, where picking the oldest job is O(1) (we use the "cached" structure), and balancing the tree is O(log n). IOW, it picks the *oldest ready* job to execute now. The implementation is already in the kernel, and this commit only changes the default GPU scheduling algorithm to use. This was tested and achieves about 1% faster performance over the Round Robin algorithm. Cc: Christian König <christian.koenig@amd.com> Cc: Alex Deucher <Alexander.Deucher@amd.com> Cc: Direct Rendering Infrastructure - Development <dri-devel@lists.freedesktop.org> Signed-off-by: Luben Tuikov <luben.tuikov@amd.com> Reviewed-by: Christian König <christian.koenig@amd.com> Link: https://patchwork.freedesktop.org/patch/msgid/20221024212634.27230-1-luben.tuikov@amd.comSigned-off-by: Christian König <christian.koenig@amd.com>
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