Mario Scheithauer has uploaded this change for review. ( https://review.coreboot.org/c/coreboot/+/35242 )
Change subject: mb/siemens/mc_apl5: Disable IGD if no EDID data available ......................................................................
mb/siemens/mc_apl5: Disable IGD if no EDID data available
To avoid possible panel failures due to incorrect timing settings for PTN3460, the internal graphic device should be disabled.
Change-Id: Ie0b9ed99fb78461bb48d6f2ff328643cd8c2cd15 Signed-off-by: Mario Scheithauer mario.scheithauer@siemens.com --- M src/mainboard/siemens/mc_apl1/variants/mc_apl5/ptn3460.c 1 file changed, 25 insertions(+), 0 deletions(-)
git pull ssh://review.coreboot.org:29418/coreboot refs/changes/42/35242/1
diff --git a/src/mainboard/siemens/mc_apl1/variants/mc_apl5/ptn3460.c b/src/mainboard/siemens/mc_apl1/variants/mc_apl5/ptn3460.c index f6fed97..2cc7dd4 100644 --- a/src/mainboard/siemens/mc_apl1/variants/mc_apl5/ptn3460.c +++ b/src/mainboard/siemens/mc_apl1/variants/mc_apl5/ptn3460.c @@ -16,9 +16,32 @@ #include <console/console.h> #include <hwilib.h> #include <device/i2c_simple.h> +#include <device/pci_ops.h> +#include <soc/pci_devs.h> #include <types.h> #include <variant/ptn3460.h>
+static void igd_disable(void) +{ + struct device *root_dev = pcidev_path_on_root(SA_DEVFN_ROOT); + uint8_t deven; + uint16_t ggc; + + /* GMCH Graphics Control Register */ + ggc = pci_read_config16(root_dev, 0x50); + /* Set size of Graphics Translation Table Memory (GGMS) [7:6] + * to 0 and select 0 MB for Graphics Memory (GMS) [15:8]. */ + ggc &= ~(0xffc0); + /* Disable IGD VGA (IVD). */ + ggc |= 0x2; + pci_write_config16(root_dev, 0x50, ggc); + /* Device Enable Register */ + deven = pci_read_config8(root_dev, 0x54); + /* Disable IGD device (D2F0EN). */ + deven &= ~(0x10); + pci_write_config8(root_dev, 0x54, deven); +} + /** * This function sets up the DP2LVDS-converter to be used with the appropriate * lcd panel. @@ -42,6 +65,8 @@ /* Get all needed information from hwinfo block. */ if (hwilib_get_field(Edid, edid_data, sizeof(edid_data)) != sizeof(edid_data)) { + /* Disable IGD to avoid panel failures. */ + igd_disable(); printk(BIOS_ERR, "LCD: No EDID data available in %s\n", hwi_block); return 1;