pan/kmod: Expose the BO flags supported by a pan_kmod_device

Will be needed to let the frontend know if it can use cached CPU-mappings,
and it allows us to extend the set of supported flags without introducing
a new field if we ever have to.

Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Christoph Pillmayer <christoph.pillmayer@arm.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/36385>

src/panfrost/lib/kmod/pan_kmod.h

@@ -102,6 +102,13 @@ enum pan_kmod_bo_flags {
     * is called.
     */
    PAN_KMOD_BO_FLAG_GPU_UNCACHED = BITFIELD_BIT(5),
+
+   /* CPU map the buffer object in userspace by forcing the "Write-Back
+    * Cacheable" cacheability attribute. The mapping otherwise uses the
+    * "Non-Cacheable" attribute if the ACE-Lite coherency protocol isn't
+    * supported by the GPU.
+    */
+   PAN_KMOD_BO_FLAG_WB_MMAP = BITFIELD_BIT(6),
 };
 
 /* Allowed group priority flags. */
@@ -213,6 +220,9 @@ struct pan_kmod_dev_props {
 
    /* A mask of flags containing the allowed group priorities. */
    enum pan_kmod_group_allow_priority_flags allowed_group_priorities_mask;
+
+   /* Mask of BO flags supported by the KMD. */
+   uint32_t supported_bo_flags;
 };
 
 /* Memory allocator for kmod internal allocations. */

src/panfrost/lib/kmod/panfrost_kmod.c

@@ -197,6 +197,12 @@ panfrost_dev_query_props(struct panfrost_kmod_dev *panfrost_dev)
    if (prios & BITFIELD_BIT(PANFROST_JM_CTX_PRIORITY_HIGH))
       props->allowed_group_priorities_mask |=
          PAN_KMOD_GROUP_ALLOW_PRIORITY_HIGH;
+
+   props->supported_bo_flags = PAN_KMOD_BO_FLAG_EXECUTABLE |
+                               PAN_KMOD_BO_FLAG_ALLOC_ON_FAULT |
+                               PAN_KMOD_BO_FLAG_NO_MMAP;
+   if (pan_kmod_driver_version_at_least(&dev->driver, 1, 6))
+      props->supported_bo_flags |= PAN_KMOD_BO_FLAG_WB_MMAP;
 }
 
 static struct pan_kmod_dev *
@@ -250,6 +256,11 @@ to_panfrost_bo_flags(struct pan_kmod_dev *dev, uint32_t flags)
          panfrost_flags |= PANFROST_BO_NOEXEC;
    }
 
+   if (flags & PAN_KMOD_BO_FLAG_WB_MMAP) {
+      assert(!(flags & PAN_KMOD_BO_FLAG_NO_MMAP));
+      panfrost_flags |= PANFROST_BO_WB_MMAP;
+   }
+
    return panfrost_flags;
 }
 

src/panfrost/lib/kmod/panthor_kmod.c

@@ -171,12 +171,18 @@ panthor_dev_query_props(struct panthor_kmod_dev *panthor_dev)
 
       .allowed_group_priorities_mask = to_kmod_group_allow_priority_flags(
          panthor_dev->props.group_priorities.allowed_mask),
+
+      .supported_bo_flags = PAN_KMOD_BO_FLAG_EXECUTABLE |
+                            PAN_KMOD_BO_FLAG_NO_MMAP |
+                            PAN_KMOD_BO_FLAG_GPU_UNCACHED,
    };
 
-   if (panthor_dev->base.driver.version.major > 1 ||
-       panthor_dev->base.driver.version.minor >= 6)
+   if (pan_kmod_driver_version_at_least(&panthor_dev->base.driver, 1, 6))
       props->timestamp_device_coherent = true;
 
+   if (pan_kmod_driver_version_at_least(&panthor_dev->base.driver, 1, 7))
+      props->supported_bo_flags |= PAN_KMOD_BO_FLAG_WB_MMAP;
+
    static_assert(sizeof(props->texture_features) ==
                     sizeof(panthor_dev->props.gpu.texture_features),
                  "Mismatch in texture_features array size");
@@ -333,6 +339,11 @@ to_panthor_bo_flags(uint32_t flags)
    if (flags & PAN_KMOD_BO_FLAG_NO_MMAP)
       panthor_flags |= DRM_PANTHOR_BO_NO_MMAP;
 
+   if (flags & PAN_KMOD_BO_FLAG_WB_MMAP) {
+      assert(!(flags & PAN_KMOD_BO_FLAG_NO_MMAP));
+      panthor_flags |= DRM_PANTHOR_BO_WB_MMAP;
+   }
+
    return panthor_flags;
 }