[coreboot-gerrit] Patch set updated for coreboot: intel sandybridge: don't turn off PEG

[Patrick Rudolph (siro@das-labor.org)]

Patrick Rudolph (siro at das-labor.org) just uploaded a new patch set to gerrit, which you can find at http://review.coreboot.org/11058

-gerrit

commit 2aebc87ad7658cdf0f295b1a25ee479c27d21485
Author: Patrick Rudolph <siro at das-labor.org>
Date:   Tue Jul 28 07:51:10 2015 +0200

    intel sandybridge: don't turn off PEG
    
    Don't disable PEG bits while turning on IGD.
    Fixes PCI device enumeration of PEG devices.
    
    Test system:
         * Intel Pentium CPU G2130
         * Gigabyte GA-B75M-D3H
    
    Change-Id: I2d6522504e4404f2d57f9c319351d08317aefdcb
    Signed-off-by: Patrick Rudolph <siro at das-labor.org>
---
 src/northbridge/intel/sandybridge/early_init.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/northbridge/intel/sandybridge/early_init.c b/src/northbridge/intel/sandybridge/early_init.c
index e77cf22..7b60ec7 100644
--- a/src/northbridge/intel/sandybridge/early_init.c
+++ b/src/northbridge/intel/sandybridge/early_init.c
@@ -155,6 +155,7 @@ static void sandybridge_setup_graphics(void)
 void sandybridge_early_initialization(int chipset_type)
 {
 	u32 capid0_a;
+	u32 deven;
 	u8 reg8;
 
 	/* Device ID Override Enable should be done very early */
@@ -172,8 +173,9 @@ void sandybridge_early_initialization(int chipset_type)
 	/* Setup all BARs required for early PCIe and raminit */
 	sandybridge_setup_bars();
 
-	/* Device Enable */
-	pci_write_config32(PCI_DEV(0, 0, 0), DEVEN, DEVEN_HOST | DEVEN_IGD);
+	/* Device Enable, don't touch PEG bits */
+	deven = pci_read_config32(PCI_DEV(0, 0, 0), DEVEN) | DEVEN_IGD;
+	pci_write_config32(PCI_DEV(0, 0, 0), DEVEN, deven);
 
 	sandybridge_setup_graphics();
 }