Re: [Bug #16891] Kernel panic while loading intel module during boot

[Anisse Astier <anisse-fwwRqrJYcP2HXe+LvDLADg@public.gmane.org>]

On Sun,  3 Oct 2010 23:53:02 +0200 (CEST), "Rafael J. Wysocki" <rjw-KKrjLPT3xs0@public.gmane.org> wrote :

> This message has been generated automatically as a part of a report
> of regressions introduced between 2.6.34 and 2.6.35.
> 
> The following bug entry is on the current list of known regressions
> introduced between 2.6.34 and 2.6.35.  Please verify if it still should
> be listed and let the tracking team know (either way).
> 
> 
> Bug-Entry	: http://bugzilla.kernel.org/show_bug.cgi?id=16891
> Subject		: Kernel panic while loading intel module during boot
> Submitter	: Anisse Astier <anisse-fwwRqrJYcP2HXe+LvDLADg@public.gmane.org>
> Date		: 2010-08-24 13:19 (41 days old)
> 
> 

This bug is still valid, and should be listed as a regression.
I tried to upload on bugzilla a patch authored by Daniel Vetter that fixes
the problem, but then bugzilla went into blackhole mode.

I'll provide this patch here in the meantime in case anyone is interested.

Regards,
Anisse

---
From: Daniel Vetter <daniel.vetter-/w4YWyX8dFk@public.gmane.org>
Date: Fri, 1 Oct 2010 19:52:09 +0200
Subject: [PATCH] intel-gtt: fix 2.6.35 regression

Port of commit "intel-gtt: fix gtt_total_entries detection" to 2.6.35.

Also adds PINEVIEW_IG to IS_G33 detection list

Signed-off-by: Anisse Astier <anisse-fwwRqrJYcP2HXe+LvDLADg@public.gmane.org>
---
 drivers/char/agp/intel-agp.h |    1 +
 drivers/char/agp/intel-gtt.c |   63 ++++++++++++++++++------------------------
 2 files changed, 28 insertions(+), 36 deletions(-)

diff --git a/drivers/char/agp/intel-agp.h b/drivers/char/agp/intel-agp.h
index bc9a4ad..2fbbe63 100644
--- a/drivers/char/agp/intel-agp.h
+++ b/drivers/char/agp/intel-agp.h
@@ -226,6 +226,7 @@
 		agp_bridge->dev->device == PCI_DEVICE_ID_INTEL_Q35_HB || \
 		agp_bridge->dev->device == PCI_DEVICE_ID_INTEL_Q33_HB || \
 		agp_bridge->dev->device == PCI_DEVICE_ID_INTEL_PINEVIEW_M_HB || \
+		agp_bridge->dev->device == PCI_DEVICE_ID_INTEL_PINEVIEW_IG || \
 		agp_bridge->dev->device == PCI_DEVICE_ID_INTEL_PINEVIEW_HB)
 
 #define IS_PINEVIEW (agp_bridge->dev->device == PCI_DEVICE_ID_INTEL_PINEVIEW_M_HB || \
diff --git a/drivers/char/agp/intel-gtt.c b/drivers/char/agp/intel-gtt.c
index ed11c77..ea18f64 100644
--- a/drivers/char/agp/intel-gtt.c
+++ b/drivers/char/agp/intel-gtt.c
@@ -501,7 +501,7 @@ static void intel_i830_init_gtt_entries(void)
 
 	pci_read_config_word(agp_bridge->dev, I830_GMCH_CTRL, &gmch_ctrl);
 
-	if (IS_I965) {
+	if (IS_G33 || IS_I965) {
 		u32 pgetbl_ctl;
 		pgetbl_ctl = readl(intel_private.registers+I810_PGETBL_CTL);
 
@@ -534,22 +534,6 @@ static void intel_i830_init_gtt_entries(void)
 			size = 512;
 		}
 		size += 4; /* add in BIOS popup space */
-	} else if (IS_G33 && !IS_PINEVIEW) {
-	/* G33's GTT size defined in gmch_ctrl */
-		switch (gmch_ctrl & G33_PGETBL_SIZE_MASK) {
-		case G33_PGETBL_SIZE_1M:
-			size = 1024;
-			break;
-		case G33_PGETBL_SIZE_2M:
-			size = 2048;
-			break;
-		default:
-			dev_info(&agp_bridge->dev->dev,
-				 "unknown page table size 0x%x, assuming 512KB\n",
-				(gmch_ctrl & G33_PGETBL_SIZE_MASK));
-			size = 512;
-		}
-		size += 4;
 	} else if (IS_G4X || IS_PINEVIEW) {
 		/* On 4 series hardware, GTT stolen is separate from graphics
 		 * stolen, ignore it in stolen gtt entries counting.  However,
@@ -1220,24 +1204,31 @@ static int intel_i915_get_gtt_size(void)
 	int size;
 
 	if (IS_G33) {
-		u16 gmch_ctrl;
+		u32 pgetbl_ctl;
+		pgetbl_ctl = readl(intel_private.registers+I810_PGETBL_CTL);
 
-		/* G33's GTT size defined in gmch_ctrl */
-		pci_read_config_word(agp_bridge->dev, I830_GMCH_CTRL, &gmch_ctrl);
-		switch (gmch_ctrl & I830_GMCH_GMS_MASK) {
-		case I830_GMCH_GMS_STOLEN_512:
+		switch (pgetbl_ctl & I965_PGETBL_SIZE_MASK) {
+		case I965_PGETBL_SIZE_128KB:
+			size = 128;
+			break;
+		case I965_PGETBL_SIZE_256KB:
+			size = 256;
+			break;
+		case I965_PGETBL_SIZE_512KB:
 			size = 512;
 			break;
-		case I830_GMCH_GMS_STOLEN_1024:
+		case I965_PGETBL_SIZE_1MB:
 			size = 1024;
 			break;
-		case I830_GMCH_GMS_STOLEN_8192:
-			size = 8*1024;
+		case I965_PGETBL_SIZE_2MB:
+			size = 2048;
+			break;
+		case I965_PGETBL_SIZE_1_5MB:
+			size = 1024 + 512;
 			break;
 		default:
-			dev_info(&agp_bridge->dev->dev,
-				 "unknown page table size 0x%x, assuming 512KB\n",
-				(gmch_ctrl & I830_GMCH_GMS_MASK));
+			dev_info(&intel_private.pcidev->dev,
+				 "unknown page table size, assuming 512KB\n");
 			size = 512;
 		}
 	} else {
@@ -1269,14 +1260,6 @@ static int intel_i915_create_gatt_table(struct agp_bridge_data *bridge)
 	pci_read_config_dword(intel_private.pcidev, I915_MMADDR, &temp);
 	pci_read_config_dword(intel_private.pcidev, I915_PTEADDR, &temp2);
 
-	gtt_map_size = intel_i915_get_gtt_size();
-
-	intel_private.gtt = ioremap(temp2, gtt_map_size);
-	if (!intel_private.gtt)
-		return -ENOMEM;
-
-	intel_private.gtt_total_size = gtt_map_size / 4;
-
 	temp &= 0xfff80000;
 
 	intel_private.registers = ioremap(temp, 128 * 4096);
@@ -1285,6 +1268,14 @@ static int intel_i915_create_gatt_table(struct agp_bridge_data *bridge)
 		return -ENOMEM;
 	}
 
+	gtt_map_size = intel_i915_get_gtt_size();
+
+	intel_private.gtt = ioremap(temp2, gtt_map_size);
+	if (!intel_private.gtt)
+		return -ENOMEM;
+
+	intel_private.gtt_total_size = gtt_map_size / 4;
+
 	temp = readl(intel_private.registers+I810_PGETBL_CTL) & 0xfffff000;
 	global_cache_flush();	/* FIXME: ? */
 
-- 
1.7.0.6