Re: [PATCH] pci: don't enable too many HT MSI mapping

[Yinghai Lu]

please check this one
v1 is pulled by Linus from Jesse's pci tree already, and v3 is needed
to be applied on top of v1

YH
[PATCH] pci: don't enable too much HT MSI mapping -v3

Impact: fix bug

Prakash reported that his c51-mcp51 system ondie sound card doesn't work MSI
but if he hack out the HT-MSI on mcp51, the MSI will work well with sound card.

this patch rework the nv_msi_ht_cap_quirk()
and will only try to avoid to enable ht_msi on device following that root dev,
and don't touch that root dev

v3: will enable c51...

Reported-by: Prakash Punnoor <prakash@xxxxxxxxxx>
Signed-off-by: Yinghai Lu <yinghai@xxxxxxxxxx>

---
 drivers/pci/quirks.c |   31 ++++++++++++++++++++++++++-----
 1 file changed, 26 insertions(+), 5 deletions(-)

Index: linux-2.6/drivers/pci/quirks.c
===================================================================
--- linux-2.6.orig/drivers/pci/quirks.c
+++ linux-2.6/drivers/pci/quirks.c
@@ -2077,6 +2077,10 @@ static void __devinit nv_ht_enable_msi_m
 	if (!found)
 		return;
 
+	/* don't enable host_bridge directly here */
+	if (host_bridge == dev)
+		goto out;
+
 	/* root did that ! */
 	if (msi_ht_cap_enabled(host_bridge))
 		goto out;
@@ -2097,7 +2101,7 @@ static void __devinit ht_disable_msi_map
 
 		if (pci_read_config_byte(dev, pos + HT_MSI_FLAGS,
 					 &flags) == 0) {
-			dev_info(&dev->dev, "Enabling HT MSI Mapping\n");
+			dev_info(&dev->dev, "Disabling HT MSI Mapping\n");
 
 			pci_write_config_byte(dev, pos + HT_MSI_FLAGS,
 					      flags & ~HT_MSI_FLAGS_ENABLE);
@@ -2135,7 +2139,7 @@ static int __devinit ht_check_msi_mappin
 	return found;
 }
 
-static void __devinit nv_msi_ht_cap_quirk(struct pci_dev *dev)
+static void __devinit __nv_msi_ht_cap_quirk(struct pci_dev *dev, int all)
 {
 	struct pci_dev *host_bridge;
 	int pos;
@@ -2164,7 +2168,10 @@ static void __devinit nv_msi_ht_cap_quir
 		/* Host bridge is to HT */
 		if (found == 1) {
 			/* it is not enabled, try to enable it */
-			nv_ht_enable_msi_mapping(dev);
+			if (all)
+				ht_enable_msi_mapping(dev);
+			else
+				nv_ht_enable_msi_mapping(dev);
 		}
 		return;
 	}
@@ -2176,8 +2183,22 @@ static void __devinit nv_msi_ht_cap_quir
 	/* Host bridge is not to HT, disable HT MSI mapping on this device */
 	ht_disable_msi_mapping(dev);
 }
-DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_NVIDIA, PCI_ANY_ID, nv_msi_ht_cap_quirk);
-DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_AL, PCI_ANY_ID, nv_msi_ht_cap_quirk);
+
+static void __devinit nv_msi_ht_cap_quirk_all(struct pci_dev *dev)
+{
+	return __nv_msi_ht_cap_quirk(dev, 1);
+}
+
+static void __devinit nv_msi_ht_cap_quirk_leaf(struct pci_dev *dev)
+{
+	return __nv_msi_ht_cap_quirk(dev, 0);
+}
+
+/* werid?, c51/mcp51 need c51 ht msi to be enable to make mcp51 ht msi working */
+DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_NVIDIA, 0x02f0, nv_msi_ht_cap_quirk_all);
+DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_NVIDIA, PCI_ANY_ID, nv_msi_ht_cap_quirk_leaf);
+
+DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_AL, PCI_ANY_ID, nv_msi_ht_cap_quirk_all);
 
 static void __devinit quirk_msi_intx_disable_bug(struct pci_dev *dev)
 {