[Intel-gfx] [PATCH 1/1] intel: query for LLC support

[Eugeni Dodonov]

This adds support for querying the kernel about the LLC support in the
hardware.

In case the ioctl fails, we assume that it is present on GEN6 and GEN7.

Signed-off-by: Eugeni Dodonov <eugeni.dodonov at intel.com>
---
 include/drm/i915_drm.h   |    1 +
 intel/intel_bufmgr_gem.c |   12 ++++++++++++
 2 files changed, 13 insertions(+), 0 deletions(-)

diff --git a/include/drm/i915_drm.h b/include/drm/i915_drm.h
index de72496..af3ce17 100644
--- a/include/drm/i915_drm.h
+++ b/include/drm/i915_drm.h
@@ -287,6 +287,7 @@ typedef struct drm_i915_irq_wait {
 #define I915_PARAM_HAS_EXEC_CONSTANTS	 14
 #define I915_PARAM_HAS_RELAXED_DELTA	 15
 #define I915_PARAM_HAS_GEN7_SOL_RESET	 16
+#define I915_PARAM_HAS_LLC		 17
 
 typedef struct drm_i915_getparam {
 	int param;
diff --git a/intel/intel_bufmgr_gem.c b/intel/intel_bufmgr_gem.c
index 2b4fab1..9bbf10d 100644
--- a/intel/intel_bufmgr_gem.c
+++ b/intel/intel_bufmgr_gem.c
@@ -107,6 +107,7 @@ typedef struct _drm_intel_bufmgr_gem {
 	unsigned int has_bsd : 1;
 	unsigned int has_blt : 1;
 	unsigned int has_relaxed_fencing : 1;
+	unsigned int has_llc : 1;
 	unsigned int bo_reuse : 1;
 	bool fenced_relocs;
 } drm_intel_bufmgr_gem;
@@ -2352,6 +2353,17 @@ drm_intel_bufmgr_gem_init(int fd, int batch_size)
 	ret = drmIoctl(bufmgr_gem->fd, DRM_IOCTL_I915_GETPARAM, &gp);
 	bufmgr_gem->has_relaxed_fencing = ret == 0;
 
+	gp.param = I915_PARAM_HAS_LLC;
+	ret = drmIoctl(bufmgr_gem->fd, DRM_IOCTL_I915_GETPARAM, &gp);
+	if (ret == -EINVAL) {
+		/* Kernel does not supports HAS_LLC query, fallback to GPU
+		 * generation detection and assume that we have LLC on GEN6/7
+		 */
+		bufmgr_gem->has_llc = (IS_GEN6(bufmgr_gem->pci_device) |
+				IS_GEN7(bufmgr_gem->pci_device));
+	}
+	bufmgr_gem->has_llc = ret == 0;
+
 	if (bufmgr_gem->gen < 4) {
 		gp.param = I915_PARAM_NUM_FENCES_AVAIL;
 		gp.value = &bufmgr_gem->available_fences;
-- 
1.7.8.3