diff options
author | Yinghai Lu <yinghai@kernel.org> | 2014-11-19 14:30:32 -0700 |
---|---|---|
committer | Bjorn Helgaas <bhelgaas@google.com> | 2014-11-19 14:30:32 -0700 |
commit | 7fc986d8a9727e5d40da3c2c1c343da6142e82a9 (patch) | |
tree | 0f807067986ae5145945395aa499dd15c2291dac /drivers/pci | |
parent | 7a1562d4f2d01721ad07c3a326db7512077ceea9 (diff) | |
download | op-kernel-dev-7fc986d8a9727e5d40da3c2c1c343da6142e82a9.zip op-kernel-dev-7fc986d8a9727e5d40da3c2c1c343da6142e82a9.tar.gz |
PCI: Support 64-bit bridge windows if we have 64-bit dma_addr_t
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>
CC: stable@vger.kernel.org # v3.14+
Diffstat (limited to 'drivers/pci')
-rw-r--r-- | drivers/pci/probe.c | 28 |
1 files changed, 16 insertions, 12 deletions
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 6244b18..c8ca98c 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -407,15 +407,16 @@ 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; @@ -429,17 +430,20 @@ 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; |