path: root/arch/ia64/mm/ioremap.c
AgeCommit message (Collapse)Author
2007-03-30[IA64] make ioremap avoid unsupported attributesBjorn Helgaas
Example memory map (from HP sx1000 with VGA enabled): 0x00000 - 0x9FFFF supports only WB (cacheable) access 0xA0000 - 0xBFFFF supports only UC (uncacheable) access 0xC0000 - 0xFFFFF supports only WB (cacheable) access pci_read_rom() indirectly uses ioremap(0xC0000) to read the shadow VGA option ROM. ioremap() used to default to a 16MB or 64MB UC kernel identity mapping, which would cause an MCA when reading 0xC0000 since only WB is supported there. X uses reads the option ROM to initialize devices. A smaller test case is: # echo 1 > /sys/bus/pci/devices/0000:aa:03.0/rom # cp /sys/bus/pci/devices/0000:aa:03.0/rom x To avoid this, we can use the same ioremap_page_range() strategy that most architectures use for all ioremaps. These page table mappings come out of the vmalloc area. On ia64, these are in region 5 (0xA... addresses) and typically use 16KB or 64KB mappings instead of 16MB or 64MB mappings. The smaller mappings give more flexibility to use the correct attributes. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
2007-03-30[IA64] rename ioremap variables to match i386Bjorn Helgaas
No functional change, just use the same names as i386. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
2006-08-02[IA64] sparse cleanupsKeith Owens
Fix some sparse warnings on ia64. Large constants that should be long instead of int. Use NULL instead of 0. Add some missing __iomem casts. Replace a non-C99 structure assignment. Signed-off-by: Keith Owens <kaos@sgi.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
2006-05-08[IA64] rework memory attribute aliasingBjorn Helgaas
This closes a couple holes in our attribute aliasing avoidance scheme: - The current kernel fails mmaps of some /dev/mem MMIO regions because they don't appear in the EFI memory map. This keeps X from working on the Intel Tiger box. - The current kernel allows UC mmap of the 0-1MB region of /sys/.../legacy_mem even when the chipset doesn't support UC access. This causes an MCA when starting X on HP rx7620 and rx8620 boxes in the default configuration. There's more detail in the Documentation/ia64/aliasing.txt file this adds, but the general idea is that if a region might be covered by a granule-sized kernel identity mapping, any access via /dev/mem or mmap must use the same attribute as the identity mapping. Otherwise, we fall back to using an attribute that is supported according to the EFI memory map, or to using UC if the EFI memory map doesn't mention the region. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
2006-03-30[IA64] ioremap() should prefer WB over UCBjorn Helgaas
efi_memmap_init() collects full granules of WB memory, without regard for whether they also support UC. So in order for ioremap() to work for main memory, it must prefer WB mappings when possible. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Signed-off-by: Tony Luck <tony.luck@intel.com>
2006-03-26[PATCH] ia64: ioremap: check EFI for valid memory attributesBjorn Helgaas
Check the EFI memory map so we can use the correct memory attributes for ioremap(). Previously, we always used uncacheable access, which blows up on some machines for regular system memory. Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com> Cc: Matt Domsch <Matt_Domsch@dell.com> Cc: "Tolentino, Matthew E" <matthew.e.tolentino@intel.com> Cc: "Brown, Len" <len.brown@intel.com> Cc: Andi Kleen <ak@muc.de> Acked-by: "Luck, Tony" <tony.luck@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>