Sometimes the registers claiming the aperture size on 9XX chipsets lie.

So instead, use the size of the aperture BAR to determine the aperture
size for agp_i810, and don't let the 855 and above have the aperture
set. Next to nothing uses it anyway so no harm.

introduce generic_{get,set} aperture which has this behaviour so other
drivers may use it if useful.

Change inspired by what freebsd did after i noticed my aperture size was
wrong.

Tested by many, ok kettenis@.

3 files changed, 32 insertions, 95 deletions

diff --git a/sys/dev/pci/agp.c b/sys/dev/pci/agp.c
index 5ceac833b99..cfb0aa86ecc 100644
--- a/sys/dev/pci/agp.c
+++ b/sys/dev/pci/agp.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: agp.c,v 1.18 2008/03/23 08:36:41 damien Exp $ */
+/* $OpenBSD: agp.c,v 1.19 2008/03/23 19:54:47 oga Exp $ */
 /*-
  * Copyright (c) 2000 Doug Rabson
  * All rights reserved.
@@ -361,6 +361,21 @@ agp_map_aperture(struct pci_attach_args *pa, struct agp_softc *sc, u_int32_t bar
 	return (0);
 }
 
+u_int32_t
+agp_generic_get_aperture(struct agp_softc *sc)
+{
+	return (sc->sc_apsize);
+}
+
+int
+agp_generic_set_aperture(struct agp_softc *sc, u_int32_t aperture)
+{
+	if (aperture != AGP_GET_APERTURE(sc))
+		return (EINVAL);
+
+	return (0);
+}
+
 struct agp_gatt *
 agp_alloc_gatt(struct agp_softc *sc)
 {
diff --git a/sys/dev/pci/agp_i810.c b/sys/dev/pci/agp_i810.c
index ddf397cd12a..67fbb6ee66c 100644
--- a/sys/dev/pci/agp_i810.c
+++ b/sys/dev/pci/agp_i810.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: agp_i810.c,v 1.33 2008/03/23 08:36:41 damien Exp $	*/
+/*	$OpenBSD: agp_i810.c,v 1.34 2008/03/23 19:54:47 oga Exp $	*/
 /*	$NetBSD: agp_i810.c,v 1.15 2003/01/31 00:07:39 thorpej Exp $	*/
 
 /*-
@@ -86,7 +86,6 @@ struct agp_i810_softc {
 };
 
 int	agp_i810_vgamatch(struct pci_attach_args *);
-u_int32_t agp_i810_get_aperture(struct agp_softc *);
 int	agp_i810_set_aperture(struct agp_softc *, u_int32_t);
 int	agp_i810_bind_page(struct agp_softc *, off_t, bus_addr_t);
 int	agp_i810_unbind_page(struct agp_softc *, off_t);
@@ -100,7 +99,7 @@ int	agp_i810_unbind_memory(struct agp_softc *, struct agp_memory *);
 void	agp_i810_write_gatt(struct agp_i810_softc *, bus_size_t, u_int32_t);
 
 struct agp_methods agp_i810_methods = {
-	agp_i810_get_aperture,
+	agp_generic_get_aperture,
 	agp_i810_set_aperture,
 	agp_i810_bind_page,
 	agp_i810_unbind_page,
@@ -490,63 +489,15 @@ agp_i810_detach(struct agp_softc *sc)
 }
 #endif
 
-u_int32_t
-agp_i810_get_aperture(struct agp_softc *sc)
-{
-	struct agp_i810_softc *isc = sc->sc_chipc;
-	pcireg_t reg;
-
-	if (isc->chiptype == CHIP_I810) {
-		u_int16_t miscc;
-
-		reg = pci_conf_read(sc->sc_pc, sc->sc_pcitag, AGP_I810_SMRAM);
-		miscc = (u_int16_t)(reg >> 16);
-		if ((miscc & AGP_I810_MISCC_WINSIZE) ==
-		    AGP_I810_MISCC_WINSIZE_32)
-			return (32 * 1024 * 1024);
-		else
-			return (64 * 1024 * 1024);
-	} else if (isc->chiptype == CHIP_I830) {
-		u_int16_t gcc1;
-
-		reg = pci_conf_read(sc->sc_pc, sc->sc_pcitag, AGP_I830_GCC0);
-		gcc1 = (u_int16_t)(reg >> 16);
-		if ((gcc1 & AGP_I830_GCC1_GMASIZE) == AGP_I830_GCC1_GMASIZE_64)
-			return (64 * 1024 * 1024);
-		else
-			return (128 * 1024 * 1024);
-	} else if (isc->chiptype == CHIP_I915 || isc->chiptype == CHIP_G33) {
-		reg = pci_conf_read(sc->sc_pc, sc->sc_pcitag, AGP_I915_MSAC);
-		if ((reg & AGP_I915_MSAC_GMASIZE) == AGP_I915_MSAC_GMASIZE_128) {
-			return (128 * 1024 * 1024);
-		} else {
-			return (256 * 1024 * 1024);
-		}
-	} else if (isc->chiptype == CHIP_I965) {
-		reg = pci_conf_read(sc->sc_pc, sc->sc_pcitag, AGP_I965_MSAC);
-		switch (reg & AGP_I965_MSAC_GMASIZE) {
-		case AGP_I965_MSAC_GMASIZE_128:
-			return (128 * 1024 * 1024);
-		case AGP_I965_MSAC_GMASIZE_256:
-			return (256 * 1024 * 1024);
-		case AGP_I965_MSAC_GMASIZE_512:
-			return (512 * 1024 * 1024);
-		}
-	}
-
-	/* CHIP_I855 */
-	return (128 * 1024 * 1024);
-}
-
 int
 agp_i810_set_aperture(struct agp_softc *sc, u_int32_t aperture)
 {
 	struct agp_i810_softc *isc = sc->sc_chipc;
 	pcireg_t reg;
+	u_int16_t gcc1, miscc;
 
-	if (isc->chiptype == CHIP_I810) {
-		u_int16_t miscc;
-
+	switch (isc->chiptype) {
+	case CHIP_I810:
 		/*
 		 * Double check for sanity.
 		 */
@@ -567,9 +518,8 @@ agp_i810_set_aperture(struct agp_softc *sc, u_int32_t aperture)
 		reg &= 0x0000ffff;
 		reg |= ((pcireg_t)miscc) << 16;
 		pci_conf_write(sc->sc_pc, sc->sc_pcitag, AGP_I810_SMRAM, reg);
-	} else if (isc->chiptype == CHIP_I830) {
-		u_int16_t gcc1;
-
+		break;
+	case CHIP_I830:
 		if (aperture != (64 * 1024 * 1024) &&
 		    aperture != (128 * 1024 * 1024)) {
 			printf("agp: bad aperture size %d\n", aperture);
@@ -586,42 +536,12 @@ agp_i810_set_aperture(struct agp_softc *sc, u_int32_t aperture)
 		reg &= 0x0000ffff;
 		reg |= ((pcireg_t)gcc1) << 16;
 		pci_conf_write(sc->sc_pc, sc->sc_pcitag, AGP_I830_GCC0, reg);
-	} else if (isc->chiptype == CHIP_I915) {
-		if (aperture != (128 * 1024 * 1024) &&
-		    aperture != (256 * 1024 * 1024)) {
-			printf("agp: bad aperture size %d\n", aperture);
-			return (EINVAL);
-		}
-		reg = pci_conf_read(sc->sc_pc, sc->sc_pcitag, AGP_I915_MSAC);
-		reg &= ~AGP_I915_MSAC_GMASIZE;
-		if (aperture == (128 * 1024 * 1024))
-			reg |= AGP_I915_MSAC_GMASIZE_128;
-		else
-			reg |= AGP_I915_MSAC_GMASIZE_256;
-		pci_conf_write(sc->sc_pc, sc->sc_pcitag, AGP_I915_MSAC, reg);
-	} else if (isc->chiptype == CHIP_I965) {
-		reg = pci_conf_read(sc->sc_pc, sc->sc_pcitag, AGP_I965_MSAC);
-		reg &= ~AGP_I965_MSAC_GMASIZE;
-		switch (aperture) {
-		case (128 * 1024 * 1024):
-			reg |= AGP_I965_MSAC_GMASIZE_128;
-			break;
-		case (256 * 1024 * 1024):
-			reg |= AGP_I965_MSAC_GMASIZE_256;
-			break;
-		case (512 * 1024 * 1024):
-			reg |= AGP_I965_MSAC_GMASIZE_512;
-			break;
-		default:
-			printf("agp: bad aperture size %d\n", aperture);
-			return (EINVAL);
-		}
-		pci_conf_write(sc->sc_pc, sc->sc_pcitag, AGP_I965_MSAC, reg);
-	} else {	/* CHIP_I855, CHIP_G33 */
-		if (aperture != (128 * 1024 * 1024)) {
-			printf("agp: bad aperture size %d\n", aperture);
-			return (EINVAL);
-		}
+		break;
+	case CHIP_I855:
+	case CHIP_I915:
+	case CHIP_I965:
+	case CHIP_G33:
+		return agp_generic_set_aperture(sc, aperture);
 	}
 
 	return (0);
diff --git a/sys/dev/pci/agpvar.h b/sys/dev/pci/agpvar.h
index 2f8b9d9a495..5c5a0de6686 100644
--- a/sys/dev/pci/agpvar.h
+++ b/sys/dev/pci/agpvar.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: agpvar.h,v 1.11 2008/03/16 19:00:28 oga Exp $	*/
+/*	$OpenBSD: agpvar.h,v 1.12 2008/03/23 19:54:47 oga Exp $	*/
 /*	$NetBSD: agpvar.h,v 1.4 2001/10/01 21:54:48 fvdl Exp $	*/
 
 /*-
@@ -181,6 +181,8 @@ void	agp_set_pchb(struct pci_attach_args*);
 int	agp_find_caps(pci_chipset_tag_t, pcitag_t);
 int	agp_map_aperture(struct pci_attach_args *, 
 	    struct agp_softc *, u_int32_t, u_int32_t);
+u_int32_t agp_generic_get_aperture(struct agp_softc *);
+int	agp_generic_set_aperture(struct agp_softc *, u_int32_t);
 struct agp_gatt *
 	agp_alloc_gatt(struct agp_softc *);
 void	agp_free_gatt(struct agp_softc *, struct agp_gatt *);