[PATCH] Fix for broken SB600 64 bit DMA issue - generic way

[PATCH] Fix for broken SB600 64 bit DMA issue - generic way

[Sandor Bodo-Merle]

---
 drivers/ata/ahci.c |   68 +++++++++++++++++++++++++++++++++++++++-------------
 1 files changed, 51 insertions(+), 17 deletions(-)

diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c
index fe3eba5..9ae19a5 100644
--- a/drivers/ata/ahci.c
+++ b/drivers/ata/ahci.c
@@ -2602,33 +2602,66 @@ static void ahci_p5wdh_workaround(struct ata_host *host)
 	}
 }
 
+const static struct dmi_system_id *dmi_64bit_dma_ok = NULL;
+static int ahci_asus_m2a_vm_32bit_only(const struct dmi_system_id *);
+
 /*
- * SB600 ahci controller on ASUS M2A-VM can't do 64bit DMA with older
- * BIOS.  The oldest version known to be broken is 0901 and working is
- * 1501 which was released on 2007-10-26.  Force 32bit DMA on anything
- * older than 1501.  Please read bko#9412 for more info.
+ * There are broken MoBo's with SB600 ahci controller, which can't do
+ * 64bit DMA.
+ * So far ASUS M2A-VM with older BIOS and Gigabyte GA-MA69VM-S2
+ * were reported as broken.
  */
-static bool ahci_asus_m2a_vm_32bit_only(struct pci_dev *pdev)
+static bool ahci_broken_system_32bit_only(struct pci_dev *pdev)
 {
 	static const struct dmi_system_id sysids[] = {
 		{
+			.callback = ahci_asus_m2a_vm_32bit_only,
 			.ident = "ASUS M2A-VM",
 			.matches = {
 				DMI_MATCH(DMI_BOARD_VENDOR,
 					  "ASUSTeK Computer INC."),
 				DMI_MATCH(DMI_BOARD_NAME, "M2A-VM"),
 			},
+			.driver_data = (void *)"10/26", /* cutoff BIOS date - mm/dd */
 		},
-		{ }
+		{
+			.ident = "Gigabyte GA-MA69VM-S2",
+			.matches = {
+				DMI_MATCH(DMI_BOARD_VENDOR,
+						"Gigabyte Technology Co., Ltd."),
+				DMI_MATCH(DMI_BOARD_NAME, "GA-MA69VM-S2"),
+			},
+		},
+		{ } /* terminate list */
 	};
-	const char *cutoff_mmdd = "10/26";
-	const char *date;
-	int year;
 
+	/* No matches found */
 	if (pdev->bus->number != 0 || pdev->devfn != PCI_DEVFN(0x12, 0) ||
-	    !dmi_check_system(sysids))
+		!dmi_check_system(sysids))
+		return false;
+
+	/* Working version found by callback */
+	if (dmi_64bit_dma_ok)
 		return false;
 
+  dev_printk(KERN_WARNING, &pdev->dev, "SB600 controller can't do 64 bit DMA on this motherboard, "
+      "forcing 32bit DMA\n");
+
+  return true;
+}
+
+/*
+ * SB600 ahci controller on ASUS M2A-VM can't do 64bit DMA with older
+ * BIOS.  The oldest version known to be broken is 0901 and working is
+ * 1501 which was released on 2007-10-26.  Force 32bit DMA on anything
+ * older than 1501.  Please read bko#9412 for more info.
+ */
+static int ahci_asus_m2a_vm_32bit_only(const struct dmi_system_id *d)
+{
+	const char *cutoff_mmdd = (const char *)d->driver_data;
+	const char *date;
+	int year;
+
 	/*
 	 * Argh.... both version and date are free form strings.
 	 * Let's hope they're using the same date format across
@@ -2638,13 +2671,14 @@ static bool ahci_asus_m2a_vm_32bit_only(struct pci_dev *pdev)
 	year = dmi_get_year(DMI_BIOS_DATE);
 	if (date && strlen(date) >= 10 && date[2] == '/' && date[5] == '/' &&
 	    (year > 2007 ||
-	     (year == 2007 && strncmp(date, cutoff_mmdd, 5) >= 0)))
-		return false;
+	     (year == 2007 && strncmp(date, cutoff_mmdd, 5) >= 0))) {
+		dmi_64bit_dma_ok = d;
+		return 0;
+	}
 
-	dev_printk(KERN_WARNING, &pdev->dev, "ASUS M2A-VM: BIOS too old, "
-		   "forcing 32bit DMA, update BIOS\n");
+	printk(KERN_WARNING "ASUS M2A-VM: BIOS too old, update BIOS\n");
 
-	return true;
+	return 1;
 }
 
 static bool ahci_broken_system_poweroff(struct pci_dev *pdev)
@@ -2857,8 +2891,8 @@ static int ahci_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 	if (board_id == board_ahci_sb700 && pdev->revision >= 0x40)
 		hpriv->flags &= ~AHCI_HFLAG_IGN_SERR_INTERNAL;
 
-	/* apply ASUS M2A_VM quirk */
-	if (ahci_asus_m2a_vm_32bit_only(pdev))
+	/* apply SB600 64bit DMA quirk */
+	if (ahci_broken_system_32bit_only(pdev))
 		hpriv->flags |= AHCI_HFLAG_32BIT_ONLY;
 
 	if (!(hpriv->flags & AHCI_HFLAG_NO_MSI))
-- 
1.6.3.3

Re: [PATCH] Fix for broken SB600 64 bit DMA issue - generic way

[Tejun Heo]

Hello, Sandor, Shane.

I redid this patch with proper dmi_get_date() implementation.  Your
code was fine but the custom parsing looked a tad bit too
out-of-place.  :-(

  http://thread.gmane.org/gmane.linux.ide/42360

It would be great if you can find out whether more recent BIOSen don't
have the issue.  It would be best if you can find exactly which BIOS
revision fixes the problem by stepping through each update but if you
don't have the time then just testing the latest one should do for the
time being.

Thanks.

-- 
tejun