[coreboot-gerrit] Patch set updated for coreboot: nb/x4x: Do not enable IGD when not supported

[Arthur Heymans (arthur@aheymans.xyz)]

Arthur Heymans (arthur at aheymans.xyz) just uploaded a new patch set to gerrit, which you can find at https://review.coreboot.org/18515

-gerrit

commit fbacd523cd2e5c5ccdae0013606cb38d5497e8de
Author: Arthur Heymans <arthur at aheymans.xyz>
Date:   Sun Mar 5 10:57:02 2017 +0100

    nb/x4x: Do not enable IGD when not supported
    
    According to "Intel ® 4 Series Chipset Family datasheet" in the
    description about GGC and DEVEN, CAPID0 bit46 is said to reflect the
    presence of an internal graphic device. This would allow the P43 and
    P45 chipset variants to work.
    
    Change-Id: Icdaa2862f82000de6d51278098365c63b7719f7f
    Signed-off-by: Arthur Heymans <arthur at aheymans.xyz>
---
 src/northbridge/intel/x4x/early_init.c | 25 +++++++++++++++----------
 1 file changed, 15 insertions(+), 10 deletions(-)

diff --git a/src/northbridge/intel/x4x/early_init.c b/src/northbridge/intel/x4x/early_init.c
index dfa90cc..56b7da7 100644
--- a/src/northbridge/intel/x4x/early_init.c
+++ b/src/northbridge/intel/x4x/early_init.c
@@ -56,17 +56,22 @@ void x4x_early_init(void)
 	pci_write_config8(d0f0, D0F0_PAM(5), 0x33);
 	pci_write_config8(d0f0, D0F0_PAM(6), 0x33);
 
-	/* Enable internal GFX */
-	pci_write_config32(d0f0, D0F0_DEVEN, BOARD_DEVEN);
-	/* Set preallocated IGD size from cmos */
-	u8 gfxsize;
-
-	if (get_option(&gfxsize, "gfx_uma_size") != CB_SUCCESS) {
-		/* 6 for 64MB, default if not set in cmos */
-		gfxsize = 6;
+	if (!(pci_read_config32(d0f0, D0F0_CAPID0 + 4) & (1 << (46 - 32)))) {
+		/* Enable internal GFX */
+		pci_write_config32(d0f0, D0F0_DEVEN, BOARD_DEVEN);
+		/* Set preallocated IGD size from cmos */
+		u8 gfxsize;
+
+		if (get_option(&gfxsize, "gfx_uma_size") != CB_SUCCESS) {
+			/* 6 for 64MB, default if not set in cmos */
+			gfxsize = 6;
+		}
+		pci_write_config16(d0f0, D0F0_GGC,
+				0x0100 | ((gfxsize + 1) << 4));
+	} else { /* Does not feature internal graphics */
+		pci_write_config32(d0f0, D0F0_DEVEN, D0EN | D1EN | PEG1EN);
+		pci_write_config16(d0f0, D0F0_GGC, (1 << 1));
 	}
-	pci_write_config16(d0f0, D0F0_GGC, 0x0100 | ((gfxsize + 1) << 4));
-
 	/*
 	 * Disabling IGD later is possible but somehow reclaiming its UMA
 	 * resources fails so enable/disable IGD before raminit if external