From df0700e53047662c167836bd6fdeea55d5d8dcfa Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Wed, 6 Sep 2017 20:24:24 +0100 Subject: [PATCH] drm/i915: Disable snooping (userptr, set-cache-level) on gen4 MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit The original gen4 has an issue where writes (both render and blt) into snoopable pages are lost. We've previously worked around this in userspace (ddx, igt) by simply not requesting snoopable buffers, but upon rediscovering this problem for a third time, make the kernel reject such requests with -ENODEV. This disables snooping on userspace buffers for i965g and i965gm (original gen4) machines. Signed-off-by: Chris Wilson Reviewed-by: Ville Syrjälä Link: https://patchwork.freedesktop.org/patch/msgid/20170906192424.26970-1-chris@chris-wilson.co.uk --- drivers/gpu/drm/i915/i915_pci.c | 2 ++ drivers/gpu/drm/i915/intel_device_info.c | 2 -- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_pci.c b/drivers/gpu/drm/i915/i915_pci.c index 881b5d6708aa5..e95baf3c4314e 100644 --- a/drivers/gpu/drm/i915/i915_pci.c +++ b/drivers/gpu/drm/i915/i915_pci.c @@ -168,6 +168,7 @@ static const struct intel_device_info intel_i965g_info __initconst = { .platform = INTEL_I965G, .has_overlay = 1, .hws_needs_physical = 1, + .has_snoop = false, }; static const struct intel_device_info intel_i965gm_info __initconst = { @@ -177,6 +178,7 @@ static const struct intel_device_info intel_i965gm_info __initconst = { .has_overlay = 1, .supports_tv = 1, .hws_needs_physical = 1, + .has_snoop = false, }; static const struct intel_device_info intel_g45_info __initconst = { diff --git a/drivers/gpu/drm/i915/intel_device_info.c b/drivers/gpu/drm/i915/intel_device_info.c index b17f7045c8f84..43831b09b47a0 100644 --- a/drivers/gpu/drm/i915/intel_device_info.c +++ b/drivers/gpu/drm/i915/intel_device_info.c @@ -412,8 +412,6 @@ void intel_device_info_runtime_init(struct drm_i915_private *dev_priv) else if (INTEL_INFO(dev_priv)->gen >= 9) gen9_sseu_info_init(dev_priv); - WARN_ON(info->has_snoop != !info->has_llc); - DRM_DEBUG_DRIVER("slice mask: %04x\n", info->sseu.slice_mask); DRM_DEBUG_DRIVER("slice total: %u\n", hweight8(info->sseu.slice_mask)); DRM_DEBUG_DRIVER("subslice total: %u\n", -- 2.30.2