--- linux-2.6.11-rc2-tank/drivers/video/aty/radeon_pm.c.orig	2005-01-24 23:52:17.000000000 +0200
+++ linux-2.6.11-rc2-tank/drivers/video/aty/radeon_pm.c	2005-01-25 00:00:24.000000000 +0200
@@ -25,8 +25,39 @@
 #include <asm/pmac_feature.h>
 #endif
 
+/* For detecting supported PC laptops */
+#ifdef CONFIG_X86
+#include <linux/dmi.h>
+#endif
+
 #include "ati_ids.h"
 
+#ifdef CONFIG_X86
+/* This array holds a list of supported PC laptops.
+ * Currently only few IBM models are tested.
+ * If you want to experiment, use dmidecode to find out
+ * vendor and product codes for Your laptop.
+ */
+static struct dmi_system_id __devinitdata radeonfb_dmi_table[] = {
+	{
+		.ident = "IBM ThinkPad T41 (2373-2FG)",
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "IBM"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "23732FG"),
+		},
+	},
+	{
+		/* Reported by Volker Braun <vbraun@physics.upenn.edu> */
+		.ident = "IBM ThinkPad T41 (2379-DJU)",
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "IBM"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "2379DJU"),
+		},
+	},
+	{ },
+};
+#endif
+
 void radeon_pm_disable_dynamic_mode(struct radeonfb_info *rinfo)
 {
 	u32 tmp;
@@ -853,6 +884,13 @@
 	tmp = INPLL( pllMCLK_MISC) | MCLK_MISC__EN_MCLK_TRISTATE_IN_SUSPEND;
 	OUTPLL( pllMCLK_MISC, tmp);
 
+	/* BUS_CNTL1__MOBILE_PLATORM_SEL setting is northbridge chipset
+	 * and radeon chip dependent. Thus we only enable it on Mac for
+	 * now (until we get more info on how to compute the correct 
+	 * value for various X86 bridges).
+	 */
+
+#ifdef CONFIG_PPC_PMAC
 	/* AGP PLL control */
 	if (rinfo->family <= CHIP_FAMILY_RV280) {
 		OUTREG(BUS_CNTL1, INREG(BUS_CNTL1) |  BUS_CNTL1__AGPCLK_VALID);
@@ -864,6 +902,7 @@
 		OUTREG(BUS_CNTL1, INREG(BUS_CNTL1));
 		OUTREG(BUS_CNTL1, (INREG(BUS_CNTL1) & ~0x4000) | 0x8000);
 	}
+#endif
 
 	OUTREG(CRTC_OFFSET_CNTL, (INREG(CRTC_OFFSET_CNTL)
 				  & ~CRTC_OFFSET_CNTL__CRTC_STEREO_SYNC_OUT_EN));
@@ -2748,6 +2787,24 @@
 		OUTREG(TV_DAC_CNTL, INREG(TV_DAC_CNTL) | 0x07000000);
 	}
 #endif /* defined(CONFIG_PM) && defined(CONFIG_PPC_OF) */
+
+/* The PM code also works on some PC laptops.
+ * Only a few models are actually tested so Your mileage may vary.
+ * We can do D2 on at least M7 and M9 on some IBM ThinkPad T41 models.
+ */
+#if defined(CONFIG_PM) && defined(CONFIG_X86)
+	if (dmi_check_system(radeonfb_dmi_table)) {
+		if (rinfo->is_mobility && rinfo->pm_reg &&
+		    rinfo->family <= CHIP_FAMILY_RV250)
+			rinfo->pm_mode |= radeon_pm_d2;
+
+		/* Power down TV DAC, that saves a significant amount of power,
+		 * we'll have something better once we actually have some TVOut
+		 * support
+		 */
+		OUTREG(TV_DAC_CNTL, INREG(TV_DAC_CNTL) | 0x07000000);
+	}
+#endif /* defined(CONFIG_PM) && defined(CONFIG_X86) */
 }
 
 void radeonfb_pm_exit(struct radeonfb_info *rinfo)