From: Thomas Zimmermann <tzimmermann@suse.de>
Date: Wed, 26 Nov 2025 09:40:09 +0000 (+0100)
Subject: drm/ast: Support cursor buffers objects in I/O memory
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ef4ed8621a15ea4979dd6c5bde436ae228c4bdfe;p=thirdparty%2Fkernel%2Flinux.git

drm/ast: Support cursor buffers objects in I/O memory

Copy the ARGB4444 cursor buffer to system memory if it is located in
I/O memory. While this cannot happen with ast's native GEM objects, an
imported buffer object might be on the external device's I/O memory.

If the cursor buffer is located in system memory continue to use it
directly.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Jocelyn Falempe <jfalempe@redhat.com>>
Link: https://patch.msgid.link/20251126094626.41985-3-tzimmermann@suse.de
---

diff --git a/drivers/gpu/drm/ast/ast_cursor.c b/drivers/gpu/drm/ast/ast_cursor.c
index 24d696df8fcda..8d473ed2738cf 100644
--- a/drivers/gpu/drm/ast/ast_cursor.c
+++ b/drivers/gpu/drm/ast/ast_cursor.c
@@ -191,7 +191,20 @@ static const u8 *ast_cursor_plane_get_argb4444(struct ast_cursor_plane *ast_curs
 
 	switch (fb->format->format) {
 	case DRM_FORMAT_ARGB4444:
-		argb4444 = shadow_plane_state->data[0].vaddr;
+		if (shadow_plane_state->data[0].is_iomem) {
+			struct iosys_map argb4444_dst[DRM_FORMAT_MAX_PLANES] = {
+				IOSYS_MAP_INIT_VADDR(ast_cursor_plane->argb4444),
+			};
+			unsigned int argb4444_dst_pitch[DRM_FORMAT_MAX_PLANES] = {
+				AST_HWC_PITCH,
+			};
+
+			drm_fb_memcpy(argb4444_dst, argb4444_dst_pitch,
+				      shadow_plane_state->data, fb, clip);
+			argb4444 = argb4444_dst[0].vaddr;
+		} else {
+			argb4444 = shadow_plane_state->data[0].vaddr;
+		}
 		break;
 	case DRM_FORMAT_ARGB8888:
 		{