[PATCH v2 1/1] drm/xe: Disable compression on SVM

[Matthew Brost]

This is not yet supported, forcefully disable by setting pat_index to
zero for CPU address mirror VMAs.

v2:
 - Use XE_CACHE_WB (Auld)
 - Only modify pat_index if compressed (Himal)

Cc: stable at vger.kernel.org
Fixes: b43e864af0d4 ("drm/xe/uapi: Add DRM_XE_VM_BIND_FLAG_CPU_ADDR_MIRROR")
Signed-off-by: Matthew Brost <matthew.brost at intel.com>
---
 drivers/gpu/drm/xe/xe_pat.c | 10 ++++++++++
 drivers/gpu/drm/xe/xe_pat.h | 10 ++++++++++
 drivers/gpu/drm/xe/xe_vm.c  |  7 ++++++-
 3 files changed, 26 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/xe/xe_pat.c b/drivers/gpu/drm/xe/xe_pat.c
index 2e7cb99ae87a..ac1767c812aa 100644
--- a/drivers/gpu/drm/xe/xe_pat.c
+++ b/drivers/gpu/drm/xe/xe_pat.c
@@ -154,6 +154,16 @@ static const struct xe_pat_table_entry xe2_pat_table[] = {
 static const struct xe_pat_table_entry xe2_pat_ats = XE2_PAT( 0, 0, 0, 0, 3, 3 );
 static const struct xe_pat_table_entry xe2_pat_pta = XE2_PAT( 0, 0, 0, 0, 3, 0 );
 
+bool xe_pat_index_get_comp_mode(struct xe_device *xe, u16 pat_index)
+{
+	WARN_ON(pat_index >= xe->pat.n_entries);
+
+	if (xe->pat.table != xe2_pat_table)
+		return false;
+
+	return xe->pat.table[pat_index].value & XE2_COMP_EN;
+}
+
 u16 xe_pat_index_get_coh_mode(struct xe_device *xe, u16 pat_index)
 {
 	WARN_ON(pat_index >= xe->pat.n_entries);
diff --git a/drivers/gpu/drm/xe/xe_pat.h b/drivers/gpu/drm/xe/xe_pat.h
index fa0dfbe525cd..8be2856a73af 100644
--- a/drivers/gpu/drm/xe/xe_pat.h
+++ b/drivers/gpu/drm/xe/xe_pat.h
@@ -58,4 +58,14 @@ void xe_pat_dump(struct xe_gt *gt, struct drm_printer *p);
  */
 u16 xe_pat_index_get_coh_mode(struct xe_device *xe, u16 pat_index);
 
+/**
+ * xe_pat_index_get_comp_mode() = Extract the compression mode for the given
+ * pat_index.
+ * @xe: xe device
+ * @pat_index: The pat_index to query
+ *
+ * Return: True if pat_index is compressed, False otherwise
+ */
+bool xe_pat_index_get_comp_mode(struct xe_device *xe, u16 pat_index);
+
 #endif
diff --git a/drivers/gpu/drm/xe/xe_vm.c b/drivers/gpu/drm/xe/xe_vm.c
index 432ea325677d..83f507ea7f30 100644
--- a/drivers/gpu/drm/xe/xe_vm.c
+++ b/drivers/gpu/drm/xe/xe_vm.c
@@ -2362,7 +2362,12 @@ vm_bind_ioctl_ops_create(struct xe_vm *vm, struct xe_vma_ops *vops,
 			op->map.is_cpu_addr_mirror = flags &
 				DRM_XE_VM_BIND_FLAG_CPU_ADDR_MIRROR;
 			op->map.dumpable = flags & DRM_XE_VM_BIND_FLAG_DUMPABLE;
-			op->map.pat_index = pat_index;
+			/* XXX: We don't support SVM + compression yet */
+			if (op->map.is_cpu_addr_mirror &&
+			    xe_pat_index_get_comp_mode(vm->xe, pat_index))
+				op->map.pat_index = vm->xe->pat.idx[XE_CACHE_WB];
+			else
+				op->map.pat_index = pat_index;
 			op->map.invalidate_on_bind =
 				__xe_vm_needs_clear_scratch_pages(vm, flags);
 		} else if (__op->op == DRM_GPUVA_OP_PREFETCH) {
-- 
2.34.1