drm/ast: Remove device POSTing and config from chip detection

There's way too much going on in ast_detect_chip(). Move the POST
and config code from the top of the function into the caller. No
functional changes.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Jocelyn Falempe <jfalempe@redhat.com>
Tested-by: Jocelyn Falempe <jfalempe@redhat.com> # AST2600
Link: https://patchwork.freedesktop.org/patch/msgid/20230621130032.3568-6-tzimmermann@suse.de

diff --git a/drivers/gpu/drm/ast/ast_main.c b/drivers/gpu/drm/ast/ast_main.c
index 862fdf0..c6987e0 100644 (file)
--- a/drivers/gpu/drm/ast/ast_main.c
+++ b/drivers/gpu/drm/ast/ast_main.c
@@ -44,7 +44,6 @@ static void ast_detect_config_mode(struct drm_device *dev, u32 *scu_rev)
 
        /* Defaults */
        ast->config_mode = ast_use_defaults;
-       *scu_rev = 0xffffffff;
 
        /* Check if we have device-tree properties */
        if (np && !of_property_read_u32(np, "aspeed,scu-revision-id",
@@ -92,32 +91,11 @@ static void ast_detect_config_mode(struct drm_device *dev, u32 *scu_rev)
        drm_info(dev, "P2A bridge disabled, using default configuration\n");
 }
 
-static int ast_detect_chip(struct drm_device *dev, bool *need_post)
+static int ast_detect_chip(struct drm_device *dev, bool need_post, u32 scu_rev)
 {
        struct ast_device *ast = to_ast_device(dev);
        struct pci_dev *pdev = to_pci_dev(dev->dev);
-       uint32_t jreg, scu_rev;
-
-       /*
-        * If VGA isn't enabled, we need to enable now or subsequent
-        * access to the scratch registers will fail. We also inform
-        * our caller that it needs to POST the chip
-        * (Assumption: VGA not enabled -> need to POST)
-        */
-       if (!ast_is_vga_enabled(dev)) {
-               ast_enable_vga(dev);
-               drm_info(dev, "VGA not enabled on entry, requesting chip POST\n");
-               *need_post = true;
-       } else
-               *need_post = false;
-
-
-       /* Enable extended register access */
-       ast_open_key(ast);
-       ast_enable_mmio(dev);
-
-       /* Find out whether P2A works or whether to use device-tree */
-       ast_detect_config_mode(dev, &scu_rev);
+       uint32_t jreg;
 
        /* Identify chipset */
        if (pdev->revision >= 0x50) {
@@ -195,7 +173,7 @@ static int ast_detect_chip(struct drm_device *dev, bool *need_post)
         * is at power-on reset, otherwise we'll incorrectly "detect" a
         * SIL164 when there is none.
         */
-       if (!*need_post) {
+       if (!need_post) {
                jreg = ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xa3, 0xff);
                if (jreg & 0x80)
                        ast->tx_chip_types = AST_TX_SIL164_BIT;
@@ -384,8 +362,9 @@ struct ast_device *ast_device_create(const struct drm_driver *drv,
 {
        struct drm_device *dev;
        struct ast_device *ast;
-       bool need_post;
+       bool need_post = false;
        int ret = 0;
+       u32 scu_rev = 0xffffffff;
 
        ast = devm_drm_dev_alloc(&pdev->dev, drv, struct ast_device, base);
        if (IS_ERR(ast))
@@ -420,7 +399,26 @@ struct ast_device *ast_device_create(const struct drm_driver *drv,
                        return ERR_PTR(-EIO);
        }
 
-       ast_detect_chip(dev, &need_post);
+       if (!ast_is_vga_enabled(dev)) {
+               drm_info(dev, "VGA not enabled on entry, requesting chip POST\n");
+               need_post = true;
+       }
+
+       /*
+        * If VGA isn't enabled, we need to enable now or subsequent
+        * access to the scratch registers will fail.
+        */
+       if (need_post)
+               ast_enable_vga(dev);
+
+       /* Enable extended register access */
+       ast_open_key(ast);
+       ast_enable_mmio(dev);
+
+       /* Find out whether P2A works or whether to use device-tree */
+       ast_detect_config_mode(dev, &scu_rev);
+
+       ast_detect_chip(dev, need_post, scu_rev);
 
        ret = ast_get_dram_info(dev);
        if (ret)