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authorYinghai Lu <yinghai@kernel.org>2014-11-19 14:30:32 -0700
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2014-12-06 15:55:34 -0800
commit2e99947798542d714d47e577d1c410ee8d830424 (patch)
tree0f404296e55ca5f1ef36698a8b8518bf36f587d7
parent8b25535501e3c9d8403fef20c3c272399394bc4f (diff)
PCI: Support 64-bit bridge windows if we have 64-bit dma_addr_t
commit 7fc986d8a9727e5d40da3c2c1c343da6142e82a9 upstream. Aaron reported that a 32-bit x86 kernel with Physical Address Extension (PAE) support complains about bridge prefetchable memory windows above 4GB: pci_bus 0000:00: root bus resource [mem 0x380000000000-0x383fffffffff] ... pci 0000:03:00.0: reg 0x10: [mem 0x383fffc00000-0x383fffdfffff 64bit pref] pci 0000:03:00.0: reg 0x20: [mem 0x383fffe04000-0x383fffe07fff 64bit pref] pci 0000:03:00.1: reg 0x10: [mem 0x383fffa00000-0x383fffbfffff 64bit pref] pci 0000:03:00.1: reg 0x20: [mem 0x383fffe00000-0x383fffe03fff 64bit pref] pci 0000:00:02.2: PCI bridge to [bus 03-04] pci 0000:00:02.2: bridge window [io 0x1000-0x1fff] pci 0000:00:02.2: bridge window [mem 0x91900000-0x91cfffff] pci 0000:00:02.2: can't handle 64-bit address space for bridge In this kernel, unsigned long is 32 bits and dma_addr_t is 64 bits. Previously we used "unsigned long" to hold the bridge window address. But this is a bus address, so we should use dma_addr_t instead. Use dma_addr_t to hold the bridge window base and limit. The question of whether the CPU can actually *address* the window is separate and depends on what the physical address space of the CPU is and whether the host bridge does any address translation. [bhelgaas: fix "shift count > width of type", changelog, stable tag] Fixes: d56dbf5bab8c ("PCI: Allocate 64-bit BARs above 4G when possible") Link: https://bugzilla.kernel.org/show_bug.cgi?id=88131 Reported-by: Aaron Ma <mapengyu@gmail.com> Tested-by: Aaron Ma <mapengyu@gmail.com> Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r--drivers/pci/probe.c29
1 files changed, 16 insertions, 13 deletions
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 6e34498ec9f0..34dff3a09b98 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -395,15 +395,16 @@ static void pci_read_bridge_mmio_pref(struct pci_bus *child)
{
struct pci_dev *dev = child->self;
u16 mem_base_lo, mem_limit_lo;
- unsigned long base, limit;
+ u64 base64, limit64;
+ dma_addr_t base, limit;
struct pci_bus_region region;
struct resource *res;
res = child->resource[2];
pci_read_config_word(dev, PCI_PREF_MEMORY_BASE, &mem_base_lo);
pci_read_config_word(dev, PCI_PREF_MEMORY_LIMIT, &mem_limit_lo);
- base = ((unsigned long) mem_base_lo & PCI_PREF_RANGE_MASK) << 16;
- limit = ((unsigned long) mem_limit_lo & PCI_PREF_RANGE_MASK) << 16;
+ base64 = (mem_base_lo & PCI_PREF_RANGE_MASK) << 16;
+ limit64 = (mem_limit_lo & PCI_PREF_RANGE_MASK) << 16;
if ((mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) == PCI_PREF_RANGE_TYPE_64) {
u32 mem_base_hi, mem_limit_hi;
@@ -417,18 +418,20 @@ static void pci_read_bridge_mmio_pref(struct pci_bus *child)
* this, just assume they are not being used.
*/
if (mem_base_hi <= mem_limit_hi) {
-#if BITS_PER_LONG == 64
- base |= ((unsigned long) mem_base_hi) << 32;
- limit |= ((unsigned long) mem_limit_hi) << 32;
-#else
- if (mem_base_hi || mem_limit_hi) {
- dev_err(&dev->dev, "can't handle 64-bit "
- "address space for bridge\n");
- return;
- }
-#endif
+ base64 |= (u64) mem_base_hi << 32;
+ limit64 |= (u64) mem_limit_hi << 32;
}
}
+
+ base = (dma_addr_t) base64;
+ limit = (dma_addr_t) limit64;
+
+ if (base != base64) {
+ dev_err(&dev->dev, "can't handle bridge window above 4GB (bus address %#010llx)\n",
+ (unsigned long long) base64);
+ return;
+ }
+
if (base <= limit) {
res->flags = (mem_base_lo & PCI_PREF_RANGE_TYPE_MASK) |
IORESOURCE_MEM | IORESOURCE_PREFETCH;