video: mb862xxfb: use pre-initialized configuration for PCI GDCs

If the bootloader has already initialized the display
controller, do not re-initialize it in the driver. Take over
the bootloader's configuration instead. This is already supported
for non PCI GDCs Lime and Mint. Add this functionality for PCI
GDCs Coral-P and Coral-PA. It is useful to avoid flicker and
also avoids unneeded init delays while booting.

Signed-off-by: Anatolij Gustschin <agust@denx.de>

1 files changed, 12 insertions, 4 deletions

diff --git a/drivers/video/mb862xx/mb862xxfb.c b/drivers/video/mb862xx/mb862xxfb.c
index 825795894daa..a1b81e73394c 100644
--- a/drivers/video/mb862xx/mb862xxfb.c
+++ b/drivers/video/mb862xx/mb862xxfb.c
@@ -746,13 +746,21 @@ static int coralp_init(struct mb862xxfb_par *par)
         cn = (ver & GC_CID_CNAME_MSK) >> 8;
         ver = ver & GC_CID_VERSION_MSK;
         if (cn == 3) {
+                unsigned long reg;
+
                 dev_info(par->dev, "Fujitsu Coral-%s GDC Rev.%d found\n",\
                          (ver == 6) ? "P" : (ver == 8) ? "PA" : "?",
                          par->pdev->revision);
-                outreg(host, GC_CCF, GC_CCF_CGE_166 | GC_CCF_COT_133);
-                udelay(200);
-                outreg(host, GC_MMR, GC_MMR_CORALP_EVB_VAL);
-                udelay(10);
+                reg = inreg(disp, GC_DCM1);
+                if (reg & GC_DCM01_DEN && reg & GC_DCM01_L0E)
+                        par->pre_init = 1;
+
+                if (!par->pre_init) {
+                        outreg(host, GC_CCF, GC_CCF_CGE_166 | GC_CCF_COT_133);
+                        udelay(200);
+                        outreg(host, GC_MMR, GC_MMR_CORALP_EVB_VAL);
+                        udelay(10);
+                }
                 /* Clear interrupt status */
                 outreg(host, GC_IST, 0);
         } else {