[PATCH 3/6] Blacklist PCI-E chipsets depending on Hypertransport MSI capabality

From: Brice Goglin
Date: Tue Jun 20 2006 - 22:31:09 EST


[PATCH 3/6] Blacklist PCI-E chipsets depending on Hypertransport MSI capabality

Introduce msi_ht_cap_enabled() to check the MSI capability in the
Hypertransport configuration space.
It is used in a generic quirk quirk_msi_ht_cap() to check whether
MSI is enabled on hypertransport chipset, and a nVidia specific quirk
quirk_nvidia_ck804_msi_ht_cap() where two 2 HT MSI mappings have to
be checked.
Both quirks set the PCI_BUS_FLAGS_NO_MSI flags when MSI is disabled.

Signed-off-by: Brice Goglin <brice@xxxxxxxx>
---
This patch will conflict with
pci/pci-nvidia-quirk-to-make-aer-pci-e-extended-capability-visible.patch
(currently in Greg K-H's patchset) since they both add
PCI_DEVICE_ID_NVIDIA_CK804_PCIE in pci_ids.h.
The first part of the changes in include/linux/pci_ids.h would have
to be dropped.

drivers/pci/quirks.c | 64 ++++++++++++++++++++++++++++++++++++++++++++++++
include/linux/pci_ids.h | 2 +
2 files changed, 66 insertions(+)

Index: linux-mm/drivers/pci/quirks.c
===================================================================
--- linux-mm.orig/drivers/pci/quirks.c 2006-06-20 22:03:27.000000000 -0400
+++ linux-mm/drivers/pci/quirks.c 2006-06-20 22:03:45.000000000 -0400
@@ -1557,6 +1557,70 @@
DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_8131_BRIDGE, quirk_disable_msi);
DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_SERVERWORKS, PCI_DEVICE_ID_SERVERWORKS_GCNB_LE,
quirk_disable_msi);
+
+/* Returns 1 if the HT MSI capability is found and enabled */
+static pci_bus_flags_t __devinit msi_ht_cap_enabled(struct pci_dev *dev)
+{
+ u8 cap_off;
+ int nbcap = 0;
+ cap_off = PCI_CAPABILITY_LIST - 1;
+
+ /* go through all caps looking for a hypertransport msi mapping */
+ while (pci_read_config_byte(dev, cap_off + 1, &cap_off) == 0 &&
+ nbcap++ <= 256 / 4) {
+ u32 cap_hdr;
+ if (cap_off == 0 || cap_off == 0xff)
+ break;
+ cap_off &= 0xfc;
+ /* msi mapping section according to hypertransport spec */
+ if (pci_read_config_dword(dev, cap_off, &cap_hdr) == 0
+ && (cap_hdr & 0xff) == PCI_CAP_ID_HT /* hypertransport cap */
+ && (cap_hdr & 0xf8000000) == 0xa8000000 /* msi mapping */) {
+ printk(KERN_INFO "PCI: Found HT MSI mapping on %s with capability %s\n",
+ pci_name(dev), cap_hdr & 0x10000 ? "enabled" : "disabled");
+ return (cap_hdr & 0x10000) != 0; /* msi mapping cap enabled */
+ }
+ }
+ return 0;
+}
+
+/* Check the hypertransport MSI mapping to know whether MSI is enabled or not */
+static void __devinit quirk_msi_ht_cap(struct pci_dev *dev)
+{
+ if (!dev->subordinate)
+ return;
+
+ if (!msi_ht_cap_enabled(dev)) {
+ printk(KERN_WARNING "PCI: MSI quirk detected. "
+ "PCI_BUS_FLAGS_NO_MSI set for %s subordinate bus.\n",
+ pci_name(dev));
+ dev->subordinate->bus_flags |= PCI_BUS_FLAGS_NO_MSI;
+ }
+}
+DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_SERVERWORKS, PCI_DEVICE_ID_SERVERWORKS_HT2000_PCIE, quirk_msi_ht_cap);
+
+/* The nVidia CK804 chipset may have 2 HT MSI mappings.
+ * MSI are supported if the MSI capability set in any of these mappings.
+ */
+static void __devinit quirk_nvidia_ck804_msi_ht_cap(struct pci_dev *dev)
+{
+ struct pci_dev *pdev;
+
+ if (!dev->subordinate)
+ return;
+
+ /* check HT MSI cap on this chipset and the root one.
+ * a single one having MSI is enough to be sure that MSI are supported.
+ */
+ pdev = pci_find_slot(dev->bus->number, 0);
+ if (!msi_ht_cap_enabled(dev) && !msi_ht_cap_enabled(pdev)) {
+ printk(KERN_WARNING "PCI: MSI quirk detected. "
+ "PCI_BUS_FLAGS_NO_MSI set for %s subordinate bus.\n",
+ pci_name(dev));
+ dev->subordinate->bus_flags |= PCI_BUS_FLAGS_NO_MSI;
+ }
+}
+DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_CK804_PCIE, quirk_nvidia_ck804_msi_ht_cap);
#endif /* CONFIG_PCI_MSI */

EXPORT_SYMBOL(pcie_mch_quirk);
Index: linux-mm/include/linux/pci_ids.h
===================================================================
--- linux-mm.orig/include/linux/pci_ids.h 2006-06-20 22:02:02.000000000 -0400
+++ linux-mm/include/linux/pci_ids.h 2006-06-20 22:03:30.000000000 -0400
@@ -1027,6 +1027,7 @@
#define PCI_DEVICE_ID_NVIDIA_NVENET_8 0x0056
#define PCI_DEVICE_ID_NVIDIA_NVENET_9 0x0057
#define PCI_DEVICE_ID_NVIDIA_CK804_AUDIO 0x0059
+#define PCI_DEVICE_ID_NVIDIA_CK804_PCIE 0x005d
#define PCI_DEVICE_ID_NVIDIA_NFORCE2_SMBUS 0x0064
#define PCI_DEVICE_ID_NVIDIA_NFORCE2_IDE 0x0065
#define PCI_DEVICE_ID_NVIDIA_NVENET_2 0x0066
@@ -1405,6 +1406,7 @@
#define PCI_DEVICE_ID_SERVERWORKS_LE 0x0009
#define PCI_DEVICE_ID_SERVERWORKS_GCNB_LE 0x0017
#define PCI_DEVICE_ID_SERVERWORKS_EPB 0x0103
+#define PCI_DEVICE_ID_SERVERWORKS_HT2000_PCIE 0x0132
#define PCI_DEVICE_ID_SERVERWORKS_OSB4 0x0200
#define PCI_DEVICE_ID_SERVERWORKS_CSB5 0x0201
#define PCI_DEVICE_ID_SERVERWORKS_CSB6 0x0203
-
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