Even though Sandy Bridge and Ivy Bridge have stolen memory, substracting it

from the GTT aperture doesn't make a lot of sense.  On some machines the
amount of stolen memory is the same size of even larger than the aperture!
So pretend that there is no stolen memory on these systems for now.

ok jsg@

1 files changed, 5 insertions, 73 deletions

diff --git a/sys/dev/pci/agp_i810.c b/sys/dev/pci/agp_i810.c
index c2485c9d0a1..a495fb6b08b 100644
--- a/sys/dev/pci/agp_i810.c
+++ b/sys/dev/pci/agp_i810.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: agp_i810.c,v 1.74 2013/03/18 12:02:56 jsg Exp $	*/
+/*	$OpenBSD: agp_i810.c,v 1.75 2013/04/05 22:26:41 kettenis Exp $	*/
 
 /*-
  * Copyright (c) 2000 Doug Rabson
@@ -506,79 +506,11 @@ agp_i810_attach(struct device *parent, struct device *self, void *aux)
 
 	case CHIP_SANDYBRIDGE:
 	case CHIP_IVYBRIDGE:
-
-		/* Stolen memory is set up at the beginning of the aperture by
-		 * the BIOS, consisting of the GATT followed by 4kb for the
-		 * BIOS display.
+		/*
+		 * Even though stolen memory exists on these machines,
+		 * it isn't necessarily mapped into the aperture.
 		 */
-
-		gcc1 = (u_int16_t)pci_conf_read(bpa.pa_pc, bpa.pa_tag,
-		    AGP_INTEL_SNB_GMCH_CTRL);
-
-		stolen = 4;
-
-		switch (gcc1 & AGP_INTEL_SNB_GMCH_GMS_STOLEN_MASK) {
-		case AGP_INTEL_SNB_GMCH_GMS_STOLEN_32M:
-			isc->stolen = (32768 - stolen) * 1024 / 4096;
-			break;
-		case AGP_INTEL_SNB_GMCH_GMS_STOLEN_64M:
-			isc->stolen = (65536 - stolen) * 1024 / 4096;
-			break;
-		case AGP_INTEL_SNB_GMCH_GMS_STOLEN_96M:
-			isc->stolen = (98304 - stolen) * 1024 / 4096;
-			break;
-		case AGP_INTEL_SNB_GMCH_GMS_STOLEN_128M:
-			isc->stolen = (131072 - stolen) * 1024 / 4096;
-			break;
-		case AGP_INTEL_SNB_GMCH_GMS_STOLEN_160M:
-			isc->stolen = (163840 - stolen) * 1024 / 4096;
-			break;
-		case AGP_INTEL_SNB_GMCH_GMS_STOLEN_192M:
-			isc->stolen = (196608 - stolen) * 1024 / 4096;
-			break;
-		case AGP_INTEL_SNB_GMCH_GMS_STOLEN_224M:
-			isc->stolen = (229376 - stolen) * 1024 / 4096;
-			break;
-		case AGP_INTEL_SNB_GMCH_GMS_STOLEN_256M:
-			isc->stolen = (262144 - stolen) * 1024 / 4096;
-			break;
-		case AGP_INTEL_SNB_GMCH_GMS_STOLEN_288M:
-			isc->stolen = (294912 - stolen) * 1024 / 4096;
-			break;
-		case AGP_INTEL_SNB_GMCH_GMS_STOLEN_320M:
-			isc->stolen = (327680 - stolen) * 1024 / 4096;
-			break;
-		case AGP_INTEL_SNB_GMCH_GMS_STOLEN_352M:
-			isc->stolen = (360448 - stolen) * 1024 / 4096;
-			break;
-		case AGP_INTEL_SNB_GMCH_GMS_STOLEN_384M:
-			isc->stolen = (393216 - stolen) * 1024 / 4096;
-			break;
-		case AGP_INTEL_SNB_GMCH_GMS_STOLEN_416M:
-			isc->stolen = (425984 - stolen) * 1024 / 4096;
-			break;
-		case AGP_INTEL_SNB_GMCH_GMS_STOLEN_448M:
-			isc->stolen = (458752 - stolen) * 1024 / 4096;
-			break;
-		case AGP_INTEL_SNB_GMCH_GMS_STOLEN_480M:
-			isc->stolen = (491520 - stolen) * 1024 / 4096;
-			break;
-		case AGP_INTEL_SNB_GMCH_GMS_STOLEN_512M:
-			isc->stolen = (524288 - stolen) * 1024 / 4096;
-			break;
-		default:
-			isc->stolen = 0;
-			printf("unknown memory configuration, disabling\n");
-			goto out;
-		}
-
-#ifdef DEBUG
-		if (isc->stolen > 0) {
-			printf(": detected %dk stolen memory",
-			    isc->stolen * 4);
-		} else
-			printf(": no preallocated video memory\n");
-#endif
+		isc->stolen = 0;
 
 		/* GATT address is already in there, make sure it's enabled */
 		gatt->ag_physical = READ4(AGP_I810_PGTBL_CTL) & ~1;