drm/ast: astdp: Test firmware status once during probing

Test for running ASTDP firmware during probe. Do not bother testing
this later. We cannot do much anyway if the firmware fails. Do not
initialize the ASTDP conenctor if the test fails during device probing.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reported-by: Shixiong Ou <oushixiong@kylinos.cn>
Tested-by: Shixiong Ou <oushixiong@kylinos.cn>
Reviewed-by: Jocelyn Falempe <jfalempe@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240717143319.104012-3-tzimmermann@suse.de

drivers/gpu/drm/ast/ast_dp.c

@@ -9,8 +9,6 @@
 
 bool ast_astdp_is_connected(struct ast_device *ast)
 {
-	if (!ast_get_index_reg_mask(ast, AST_IO_VGACRI, 0xD1, ASTDP_MCU_FW_EXECUTING))
-		return false;
 	if (!ast_get_index_reg_mask(ast, AST_IO_VGACRI, 0xDF, ASTDP_HPD))
 		return false;
 	if (!ast_get_index_reg_mask(ast, AST_IO_VGACRI, 0xDC, ASTDP_LINK_SUCCESS))
@@ -24,13 +22,11 @@ int ast_astdp_read_edid(struct drm_device *dev, u8 *ediddata)
 	u8 i = 0, j = 0;
 
 	/*
-	 * CRD1[b5]: DP MCU FW is executing
 	 * CRDC[b0]: DP link success
 	 * CRDF[b0]: DP HPD
 	 * CRE5[b0]: Host reading EDID process is done
 	 */
-	if (!(ast_get_index_reg_mask(ast, AST_IO_VGACRI, 0xD1, ASTDP_MCU_FW_EXECUTING) &&
-		ast_get_index_reg_mask(ast, AST_IO_VGACRI, 0xDC, ASTDP_LINK_SUCCESS) &&
+	if (!(ast_get_index_reg_mask(ast, AST_IO_VGACRI, 0xDC, ASTDP_LINK_SUCCESS) &&
 		ast_get_index_reg_mask(ast, AST_IO_VGACRI, 0xDF, ASTDP_HPD) &&
 		ast_get_index_reg_mask(ast, AST_IO_VGACRI, 0xE5,
 								ASTDP_HOST_EDID_READ_DONE_MASK))) {
@@ -64,9 +60,7 @@ int ast_astdp_read_edid(struct drm_device *dev, u8 *ediddata)
 			 */
 			mdelay(j+1);
 
-			if (!(ast_get_index_reg_mask(ast, AST_IO_VGACRI, 0xD1,
-							ASTDP_MCU_FW_EXECUTING) &&
-				ast_get_index_reg_mask(ast, AST_IO_VGACRI, 0xDC,
+			if (!(ast_get_index_reg_mask(ast, AST_IO_VGACRI, 0xDC,
 							ASTDP_LINK_SUCCESS) &&
 				ast_get_index_reg_mask(ast, AST_IO_VGACRI, 0xDF, ASTDP_HPD))) {
 				goto err_astdp_jump_out_loop_of_edid;
@@ -115,8 +109,6 @@ int ast_astdp_read_edid(struct drm_device *dev, u8 *ediddata)
 	return (~(j+256) + 1);
 
 err_astdp_edid_not_ready:
-	if (!(ast_get_index_reg_mask(ast, AST_IO_VGACRI, 0xD1, ASTDP_MCU_FW_EXECUTING)))
-		return (~0xD1 + 1);
 	if (!(ast_get_index_reg_mask(ast, AST_IO_VGACRI, 0xDC, ASTDP_LINK_SUCCESS)))
 		return (~0xDC + 1);
 	if (!(ast_get_index_reg_mask(ast, AST_IO_VGACRI, 0xDF, ASTDP_HPD)))
@@ -130,32 +122,29 @@ int ast_astdp_read_edid(struct drm_device *dev, u8 *ediddata)
 /*
  * Launch Aspeed DP
  */
-void ast_dp_launch(struct drm_device *dev)
+int ast_dp_launch(struct ast_device *ast)
 {
-	u32 i = 0;
-	u8 bDPExecute = 1;
-	struct ast_device *ast = to_ast_device(dev);
+	struct drm_device *dev = &ast->base;
+	unsigned int i = 10;
 
-	// Wait one second then timeout.
-	while (ast_get_index_reg_mask(ast, AST_IO_VGACRI, 0xD1, ASTDP_MCU_FW_EXECUTING) !=
-		ASTDP_MCU_FW_EXECUTING) {
-		i++;
-		// wait 100 ms
-		msleep(100);
+	while (i) {
+		u8 vgacrd1 = ast_get_index_reg(ast, AST_IO_VGACRI, 0xd1);
 
-		if (i >= 10) {
-			// DP would not be ready.
-			bDPExecute = 0;
+		if (vgacrd1 & AST_IO_VGACRD1_MCU_FW_EXECUTING)
 			break;
+		--i;
+		msleep(100);
 	}
-	}
-
-	if (!bDPExecute)
+	if (!i) {
 		drm_err(dev, "Wait DPMCU executing timeout\n");
+		return -ENODEV;
+	}
 
 	ast_set_index_reg_mask(ast, AST_IO_VGACRI, 0xE5,
 			       (u8) ~ASTDP_HOST_EDID_READ_DONE_MASK,
 			       ASTDP_HOST_EDID_READ_DONE);
+
+	return 0;
 }
 
 

drivers/gpu/drm/ast/ast_drv.h

@@ -471,7 +471,7 @@ void ast_init_3rdtx(struct drm_device *dev);
 /* aspeed DP */
 bool ast_astdp_is_connected(struct ast_device *ast);
 int ast_astdp_read_edid(struct drm_device *dev, u8 *ediddata);
-void ast_dp_launch(struct drm_device *dev);
+int ast_dp_launch(struct ast_device *ast);
 void ast_dp_power_on_off(struct drm_device *dev, bool no);
 void ast_dp_set_on_off(struct drm_device *dev, bool no);
 void ast_dp_set_mode(struct drm_crtc *crtc, struct ast_vbios_mode_info *vbios_mode);

drivers/gpu/drm/ast/ast_main.c

@@ -115,8 +115,10 @@ static void ast_detect_tx_chip(struct ast_device *ast, bool need_post)
 	} else if (IS_AST_GEN7(ast)) {
 		if (ast_get_index_reg_mask(ast, AST_IO_VGACRI, 0xD1, TX_TYPE_MASK) ==
 		    ASTDP_DPMCU_TX) {
+			int ret = ast_dp_launch(ast);
+
+			if (!ret)
 				ast->tx_chip_types = AST_TX_ASTDP_BIT;
-			ast_dp_launch(&ast->base);
 		}
 	}
 

drivers/gpu/drm/ast/ast_post.c

@@ -351,7 +351,7 @@ void ast_post_gpu(struct drm_device *dev)
 
 	if (IS_AST_GEN7(ast)) {
 		if (ast->tx_chip_types & AST_TX_ASTDP_BIT)
-			ast_dp_launch(dev);
+			ast_dp_launch(ast);
 	} else if (ast->config_mode == ast_use_p2a) {
 		if (IS_AST_GEN6(ast))
 			ast_post_chip_2500(dev);

drivers/gpu/drm/ast/ast_reg.h

@@ -37,6 +37,8 @@
 #define AST_IO_VGACRCB_HWC_16BPP	BIT(0) /* set: ARGB4444, cleared: 2bpp palette */
 #define AST_IO_VGACRCB_HWC_ENABLED	BIT(1)
 
+#define AST_IO_VGACRD1_MCU_FW_EXECUTING	BIT(5)
+
 #define AST_IO_VGAIR1_R			(0x5A)
 #define AST_IO_VGAIR1_VREFRESH		BIT(3)
 
@@ -67,12 +69,10 @@
 #define AST_DP_VIDEO_ENABLE		BIT(0)
 
 /*
- * CRD1[b5]: DP MCU FW is executing
  * CRDC[b0]: DP link success
  * CRDF[b0]: DP HPD
  * CRE5[b0]: Host reading EDID process is done
  */
-#define ASTDP_MCU_FW_EXECUTING		BIT(5)
 #define ASTDP_LINK_SUCCESS		BIT(0)
 #define ASTDP_HPD			BIT(0)
 #define ASTDP_HOST_EDID_READ_DONE	BIT(0)