[coreboot-gerrit] Patch set updated for coreboot: nb/intel/sandybridge/gma: add disable function

[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/11919

-gerrit

commit bb81a2eec569453cb62349a97e2bf6ca0f5f0d4a
Author: Patrick Rudolph <siro at das-labor.org>
Date:   Thu Oct 15 15:35:12 2015 +0200

    nb/intel/sandybridge/gma: add disable function
    
    Issue observed:
    In a multi GPU setup (IGD and PEG) the system still uses the IGD.
    CONFIG_ONBOARD_VGA_IS_PRIMARY has no effect on Sandy/Ivy Bridge.
    
    Test system:
    * Gigabyte GA-B75M-D3H
    * Intel Pentium CPU G2130
    * ATI Radeon HD4780
    
    Problem description:
    The GMA is missing a disable function.
    
    Problem solution:
    Add a GMA disable function. Deactivate PCI device until remaining multi
    GPU issues are resolved. Do not claim VGA decode any more.
    
    Final testing results:
    The system is able to boot using the PEG device as primary VGA
    device.
    
    Change-Id: I52af32df41ca22f808b119f3a4099849c74068b3
    Signed-off-by: Patrick Rudolph <siro at das-labor.org>
---
 src/northbridge/intel/sandybridge/gma.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/src/northbridge/intel/sandybridge/gma.c b/src/northbridge/intel/sandybridge/gma.c
index d1779db..bf340e9 100644
--- a/src/northbridge/intel/sandybridge/gma.c
+++ b/src/northbridge/intel/sandybridge/gma.c
@@ -634,6 +634,19 @@ static void gma_ssdt(device_t device)
 	drivers_intel_gma_displays_ssdt_generate(gfx);
 }
 
+/* called by pci set_vga_bridge function */
+static void gma_func0_disable(struct device *dev)
+{
+	u16 reg16;
+	device_t dev_host = dev_find_slot(0, PCI_DEVFN(0,0));
+
+	reg16 = pci_read_config16(dev_host, GGC);
+	reg16 |= (1 << 1); /* disable VGA decode */
+	pci_write_config16(dev_host, GGC, reg16);
+
+	dev->enabled = 0;
+}
+
 static struct pci_operations gma_pci_ops = {
 	.set_subsystem    = gma_set_subsystem,
 };
@@ -646,6 +659,7 @@ static struct device_operations gma_func0_ops = {
 	.init			= gma_func0_init,
 	.scan_bus		= 0,
 	.enable			= 0,
+	.disable		= gma_func0_disable,
 	.ops_pci		= &gma_pci_ops,
 };