[xen staging-4.14] VT-d: Tylersburg errata apply to further steppings

[patchbot@xxxxxxx]

commit 26b885cbdd2458b32434a4d20b921b49bd623adb
Author:     Jan Beulich <jbeulich@xxxxxxxx>
AuthorDate: Wed Aug 25 15:11:11 2021 +0200
Commit:     Jan Beulich <jbeulich@xxxxxxxx>
CommitDate: Wed Aug 25 15:11:11 2021 +0200

    VT-d: Tylersburg errata apply to further steppings
    
    While for 5500 and 5520 chipsets only B3 and C2 are mentioned in the
    spec update, X58's also mentions B2, and searching the internet suggests
    systems with this stepping are actually in use. Even worse, for X58
    erratum #69 is marked applicable even to C2. Split the check to cover
    all applicable steppings and to also report applicable errata numbers in
    the log message. The splitting requires using the DMI port instead of
    the System Management Registers device, but that's then in line (also
    revision checking wise) with the spec updates.
    
    Fixes: 6890cebc6a98 ("VT-d: deal with 5500/5520/X58 errata")
    Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
    Reviewed-by: Kevin Tian <kevin.tian@xxxxxxxxx>
    master commit: 517a90d1ca09ce00e50d46ac25566cc3bd2eb34d
    master date: 2021-08-18 09:44:14 +0200
---
 xen/drivers/passthrough/vtd/quirks.c | 34 +++++++++++++++++++++++++---------
 1 file changed, 25 insertions(+), 9 deletions(-)

diff --git a/xen/drivers/passthrough/vtd/quirks.c 
b/xen/drivers/passthrough/vtd/quirks.c
index 5594270678..1de2578378 100644
--- a/xen/drivers/passthrough/vtd/quirks.c
+++ b/xen/drivers/passthrough/vtd/quirks.c
@@ -268,26 +268,42 @@ static int __init parse_snb_timeout(const char *s)
 }
 custom_param("snb_igd_quirk", parse_snb_timeout);
 
-/* 5500/5520/X58 Chipset Interrupt remapping errata, for stepping B-3.
- * Fixed in stepping C-2. */
+/*
+ * 5500/5520/X58 chipset interrupt remapping errata, for steppings B2 and B3.
+ * Fixed in stepping C2 except on X58.
+ */
 static void __init tylersburg_intremap_quirk(void)
 {
-    uint32_t bus, device;
+    unsigned int bus;
     uint8_t rev;
 
     for ( bus = 0; bus < 0x100; bus++ )
     {
-        /* Match on System Management Registers on Device 20 Function 0 */
-        device = pci_conf_read32(PCI_SBDF(0, bus, 20, 0), PCI_VENDOR_ID);
-        rev = pci_conf_read8(PCI_SBDF(0, bus, 20, 0), PCI_REVISION_ID);
+        /* Match on DMI port (Device 0 Function 0) */
+        rev = pci_conf_read8(PCI_SBDF(0, bus, 0, 0), PCI_REVISION_ID);
 
-        if ( rev == 0x13 && device == 0x342e8086 )
+        switch ( pci_conf_read32(PCI_SBDF(0, bus, 0, 0), PCI_VENDOR_ID) )
         {
+        default:
+            continue;
+
+        case 0x34038086: case 0x34068086:
+            if ( rev >= 0x22 )
+                continue;
+            printk(XENLOG_WARNING VTDPREFIX
+                   "Disabling IOMMU due to Intel 5500/5520 chipset errata #47 
and #53\n");
+            iommu_enable = false;
+            break;
+
+        case 0x34058086:
             printk(XENLOG_WARNING VTDPREFIX
-                   "Disabling IOMMU due to Intel 5500/5520/X58 Chipset errata 
#47, #53\n");
-            iommu_enable = 0;
+                   "Disabling IOMMU due to Intel X58 chipset %s\n",
+                   rev < 0x22 ? "errata #62 and #69" : "erratum #69");
+            iommu_enable = false;
             break;
         }
+
+        break;
     }
 }
 
--
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