drm/panfrost: Add an ioctl to query BO flags

This is useful when importing BOs, so we can know about cacheability
and flush the caches when needed.

v2:
- New commit

v3:
- Add Steve's R-b

v4:
- No changes

v5:
- No changes

v6:
- No changes

v7:
- No changes

v8:
- No changes

Reviewed-by: Steven Price <steven.price@arm.com>
Link: https://patch.msgid.link/20251208100841.730527-12-boris.brezillon@collabora.com
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>

2 files changed, 52 insertions, 0 deletions

diff --git a/drivers/gpu/drm/panfrost/panfrost_drv.c b/drivers/gpu/drm/panfrost/panfrost_drv.c
index 450204fdbe45..d461ecf8829d 100644
--- a/drivers/gpu/drm/panfrost/panfrost_drv.c
+++ b/drivers/gpu/drm/panfrost/panfrost_drv.c
@@ -630,6 +630,38 @@ err_ops:
 	return ret;
 }
 
+static int panfrost_ioctl_query_bo_info(struct drm_device *dev, void *data,
+					struct drm_file *file_priv)
+{
+	struct drm_panfrost_query_bo_info *args = data;
+	struct drm_gem_object *gem_obj;
+	struct panfrost_gem_object *bo;
+
+	gem_obj = drm_gem_object_lookup(file_priv, args->handle);
+	if (!gem_obj) {
+		DRM_DEBUG("Failed to look up GEM BO %d\n", args->handle);
+		return -ENOENT;
+	}
+
+	bo = to_panfrost_bo(gem_obj);
+	args->pad = 0;
+	args->create_flags = 0;
+	args->extra_flags = 0;
+
+	if (drm_gem_is_imported(gem_obj)) {
+		args->extra_flags |= DRM_PANFROST_BO_IS_IMPORTED;
+	} else {
+		if (bo->noexec)
+			args->create_flags |= PANFROST_BO_NOEXEC;
+
+		if (bo->is_heap)
+			args->create_flags |= PANFROST_BO_HEAP;
+	}
+
+	drm_gem_object_put(gem_obj);
+	return 0;
+}
+
 int panfrost_unstable_ioctl_check(void)
 {
 	if (!unstable_ioctls)
@@ -700,6 +732,7 @@ static const struct drm_ioctl_desc panfrost_drm_driver_ioctls[] = {
 	PANFROST_IOCTL(JM_CTX_CREATE,	jm_ctx_create,	DRM_RENDER_ALLOW),
 	PANFROST_IOCTL(JM_CTX_DESTROY,	jm_ctx_destroy,	DRM_RENDER_ALLOW),
 	PANFROST_IOCTL(SYNC_BO,		sync_bo,	DRM_RENDER_ALLOW),
+	PANFROST_IOCTL(QUERY_BO_INFO,	query_bo_info,	DRM_RENDER_ALLOW),
 };
 
 static void panfrost_gpu_show_fdinfo(struct panfrost_device *pfdev,
diff --git a/include/uapi/drm/panfrost_drm.h b/include/uapi/drm/panfrost_drm.h
index e194e087a0c8..36ae48ea50d3 100644
--- a/include/uapi/drm/panfrost_drm.h
+++ b/include/uapi/drm/panfrost_drm.h
@@ -25,6 +25,7 @@ extern "C" {
 #define DRM_PANFROST_JM_CTX_CREATE		0x0a
 #define DRM_PANFROST_JM_CTX_DESTROY		0x0b
 #define DRM_PANFROST_SYNC_BO			0x0c
+#define DRM_PANFROST_QUERY_BO_INFO		0x0d
 
 #define DRM_IOCTL_PANFROST_SUBMIT		DRM_IOW(DRM_COMMAND_BASE + DRM_PANFROST_SUBMIT, struct drm_panfrost_submit)
 #define DRM_IOCTL_PANFROST_WAIT_BO		DRM_IOW(DRM_COMMAND_BASE + DRM_PANFROST_WAIT_BO, struct drm_panfrost_wait_bo)
@@ -37,6 +38,7 @@ extern "C" {
 #define DRM_IOCTL_PANFROST_JM_CTX_CREATE	DRM_IOWR(DRM_COMMAND_BASE + DRM_PANFROST_JM_CTX_CREATE, struct drm_panfrost_jm_ctx_create)
 #define DRM_IOCTL_PANFROST_JM_CTX_DESTROY	DRM_IOWR(DRM_COMMAND_BASE + DRM_PANFROST_JM_CTX_DESTROY, struct drm_panfrost_jm_ctx_destroy)
 #define DRM_IOCTL_PANFROST_SYNC_BO		DRM_IOWR(DRM_COMMAND_BASE + DRM_PANFROST_SYNC_BO, struct drm_panfrost_sync_bo)
+#define DRM_IOCTL_PANFROST_QUERY_BO_INFO	DRM_IOWR(DRM_COMMAND_BASE + DRM_PANFROST_QUERY_BO_INFO, struct drm_panfrost_query_bo_info)
 
 /*
  * Unstable ioctl(s): only exposed when the unsafe unstable_ioctls module
@@ -353,6 +355,23 @@ struct drm_panfrost_sync_bo {
 	__u32 pad;
 };
 
+/** BO comes from a different subsystem. */
+#define DRM_PANFROST_BO_IS_IMPORTED (1 << 0)
+
+struct drm_panfrost_query_bo_info {
+	/** Handle of the object being queried. */
+	__u32 handle;
+
+	/** Extra flags that are not coming from the BO_CREATE ioctl(). */
+	__u32 extra_flags;
+
+	/** Flags passed at creation time. */
+	__u32 create_flags;
+
+	/** Will be zero on return. */
+	__u32 pad;
+};
+
 /* Definitions for coredump decoding in user space */
 #define PANFROSTDUMP_MAJOR 1
 #define PANFROSTDUMP_MINOR 0