[coreboot-gerrit] Change in coreboot[master]: soc/intel/cannonlake: Fix DMAR when no iGPU is present

[Angel Pons (Code Review)]

Angel Pons has submitted this change. ( https://review.coreboot.org/c/coreboot/+/43994 )

Change subject: soc/intel/cannonlake: Fix DMAR when no iGPU is present
......................................................................

soc/intel/cannonlake: Fix DMAR when no iGPU is present

Don't emit RMRR for the iGPU if it's not present. This is done on
other platforms as well.

Fixes an DMAR error seen in dmesg on platforms without iGPU.

Change-Id: Iafe86e6938a120b707aaae935cb8168f790bb22f
Signed-off-by: Patrick Rudolph 
Reviewed-on: https://review.coreboot.org/c/coreboot/+/43994
Reviewed-by: Angel Pons 
Tested-by: build bot (Jenkins) 
---
M src/soc/intel/cannonlake/acpi.c
1 file changed, 11 insertions(+), 8 deletions(-)

Approvals:
  build bot (Jenkins): Verified
  Angel Pons: Looks good to me, approved

diff --git a/src/soc/intel/cannonlake/acpi.c b/src/soc/intel/cannonlake/acpi.c
index 3f3ba10..f061c30 100644
--- a/src/soc/intel/cannonlake/acpi.c
+++ b/src/soc/intel/cannonlake/acpi.c
@@ -285,8 +285,8 @@
    struct device *const igfx_dev = pcidev_path_on_root(SA_DEVFN_IGD);
    uint64_t gfxvtbar = MCHBAR64(GFXVTBAR) & VTBAR_MASK;
    bool gfxvten = MCHBAR32(GFXVTBAR) & VTBAR_ENABLED;
-
-	if (igfx_dev && igfx_dev->enabled && gfxvtbar && gfxvten) {
+	const bool emit_igd = igfx_dev && igfx_dev->enabled && gfxvtbar && gfxvten;
+	if (emit_igd) {
    	unsigned long tmp = current;

current += acpi_create_dmar_drhd(current, 0, 0, gfxvtbar);
@@ -326,12 +326,15 @@
    	acpi_dmar_drhd_fixup(tmp, current);
    }

-	/* Add RMRR entry */
-	const unsigned long tmp = current;
-	current += acpi_create_dmar_rmrr(current, 0,
-		sa_get_gsm_base(), sa_get_tolud_base() - 1);
-	current += acpi_create_dmar_ds_pci(current, 0, 2, 0);
-	acpi_dmar_rmrr_fixup(tmp, current);
+	/* Add RMRR entry after all DRHD entries */
+	if (emit_igd) {
+		const unsigned long tmp = current;
+
+		current += acpi_create_dmar_rmrr(current, 0,
+			sa_get_gsm_base(), sa_get_tolud_base() - 1);
+		current += acpi_create_dmar_ds_pci(current, 0, 2, 0);
+		acpi_dmar_rmrr_fixup(tmp, current);
+	}

return current;
 }