From: Christian König <christian.koenig@xxxxxxx>
Most BIOS don't enable this because of compatibility reasons.
Manually enable a 64bit BAR of 64GB size so that we have
enough room for PCI devices.
Signed-off-by: Christian König <christian.koenig at amd.com>
---
arch/x86/pci/fixup.c | 53 ++++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 53 insertions(+)
diff --git a/arch/x86/pci/fixup.c b/arch/x86/pci/fixup.c
index 6d52b94..bff5242 100644
--- a/arch/x86/pci/fixup.c
+++ b/arch/x86/pci/fixup.c
@@ -571,3 +571,56 @@ DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x2fc0, pci_invalid_bar);
DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x6f60, pci_invalid_bar);
DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x6fa0, pci_invalid_bar);
DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x6fc0, pci_invalid_bar);
+
+static void pci_amd_enable_64bit_bar(struct pci_dev *dev)
+{
+ const uint64_t size = 64ULL * 1024 * 1024 * 1024;
+ uint32_t base, limit, high;
+ struct resource *res;
+ unsigned i;
+ int r;
+
+ for (i = 0; i < 8; ++i) {
+
+ pci_read_config_dword(dev, 0x80 + i * 0x8, &base);
+ pci_read_config_dword(dev, 0x180 + i * 0x4, &high);
+
+ /* Is this slot free? */
+ if ((base & 0x3) == 0x0)
+ break;
+
+ base >>= 8;
+ base |= high << 24;
+
+ /* Abort if a slot already configures a 64bit BAR. */
+ if (base > 0x10000)
+ return;
+
+ }
+
+ if (i == 8)
+ return;
+
+ res = kzalloc(sizeof(*res), GFP_KERNEL);
+ res->flags = IORESOURCE_MEM | IORESOURCE_PREFETCH | IORESOURCE_MEM_64 |
+ IORESOURCE_WINDOW;
+ res->name = dev->bus->name;
+ r = allocate_resource(&iomem_resource, res, size, 0x100000000,
+ 0xfd00000000, size, NULL, NULL);
+ if (r) {
+ kfree(res);
+ return;
+ }
+
+ base = ((res->start >> 8) & 0xffffff00) | 0x3;
+ limit = ((res->end + 1) >> 8) & 0xffffff00;
+ high = ((res->start >> 40) & 0xff) |
+ ((((res->end + 1) >> 40) & 0xff) << 16);
+
+ pci_write_config_dword(dev, 0x180 + i * 0x4, high);
+ pci_write_config_dword(dev, 0x84 + i * 0x8, limit);
+ pci_write_config_dword(dev, 0x80 + i * 0x8, base);
+
+ pci_bus_add_resource(dev->bus, res, 0);
+}
+DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_AMD, 0x141b, pci_amd_enable_64bit_bar);
--
2.7.4
