From: Abdiel Janulgue <[email protected]> For performance writes over PCIe may not be strictly ordered by default. This provides an option to expose a kernel configuration option to disable relaxed ordering and turn on strict ordering instead for debug purposes.
Signed-off-by: Abdiel Janulgue <[email protected]> Signed-off-by: Stuart Summers <[email protected]> Cc: Matthew Auld <[email protected]> --- drivers/gpu/drm/i915/Kconfig.debug | 11 +++++++++++ drivers/gpu/drm/i915/intel_memory_region.c | 12 ++++++++++++ 2 files changed, 23 insertions(+) diff --git a/drivers/gpu/drm/i915/Kconfig.debug b/drivers/gpu/drm/i915/Kconfig.debug index 206882e154bc..114240e890aa 100644 --- a/drivers/gpu/drm/i915/Kconfig.debug +++ b/drivers/gpu/drm/i915/Kconfig.debug @@ -221,3 +221,14 @@ config DRM_I915_DEBUG_RUNTIME_PM driver loading, suspend and resume operations. If in doubt, say "N" + +config DRM_I915_PCIE_STRICT_WRITE_ORDERING + bool "Enable PCIe strict ordering " + depends on DRM_I915 + default n + help + Relaxed ordering in writes is enabled by default to improve system + performance. Strict ordering can be selected instead to assist in + debugging. + + If in doubt, say "N". diff --git a/drivers/gpu/drm/i915/intel_memory_region.c b/drivers/gpu/drm/i915/intel_memory_region.c index eeea520f97ba..d564b596efda 100644 --- a/drivers/gpu/drm/i915/intel_memory_region.c +++ b/drivers/gpu/drm/i915/intel_memory_region.c @@ -280,6 +280,18 @@ int intel_memory_regions_hw_probe(struct drm_i915_private *i915) { int err, i; + /* All platforms currently have system memory */ + GEM_BUG_ON(!HAS_REGION(i915, REGION_SMEM)); + + if (IS_DGFX(i915)) { + if (IS_ENABLED(CONFIG_DRM_I915_PCIE_STRICT_WRITE_ORDERING)) + pcie_capability_clear_word(i915->drm.pdev, PCI_EXP_DEVCTL, + PCI_EXP_DEVCTL_RELAX_EN); + else + pcie_capability_set_word(i915->drm.pdev, PCI_EXP_DEVCTL, + PCI_EXP_DEVCTL_RELAX_EN); + } + for (i = 0; i < ARRAY_SIZE(i915->mm.regions); i++) { struct intel_memory_region *mem = ERR_PTR(-ENODEV); u16 type, instance; -- 2.26.2 _______________________________________________ Intel-gfx mailing list [email protected] https://lists.freedesktop.org/mailman/listinfo/intel-gfx
