• Alexander Bigga's avatar
    [MIPS] Alchemy: Fix PCI-memory access · 8a93c496
    Alexander Bigga authored
        
        The problem was introduced in 2.6.18.3 with the casting of some
        36bit-defines (PCI memory) in au1000.h to resource_size_t which may be
        u32 or u64 depending on the experimental CONFIG_RESOURCES_64BIT.
        
        With unset CONFIG_RESOURCES_64BIT, the pci-memory cannot be accessed
        because the ioremap in arch/mips/au1000/common/pci.c already used the
        truncated addresses.
        With set CONFIG_RESOURCES_64BIT, things get even worse, because PCI-scan
        aborts, due to resource conflict: request_resource() in arch/mips/pci/pci.c
        fails because the maximum iomem-address is 0xffffffff (32bit) but the
        pci-memory-start-address is 0x440000000 (36bit).
        
        To get pci working again, I propose the following patch:
        
        1. remove the resource_size_t-casting from au1000.h again
        2. make the casting in arch/mips/au1000/common/pci.c (it's allowed and
        necessary here. The 36bit-handling will be done in __fixup_bigphys_addr).
        
        With this patch pci works again like in 2.6.18.2, the gcc-compile warnings
        in pci.c are gone and it doesn't depend on CONFIG_EXPERIMENTAL.
    Signed-off-by: default avatarAlexander Bigga <ab@mycable.de>
    Signed-off-by: default avatarRalf Baechle <ralf@linux-mips.org>
    
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    8a93c496
pci.c 3.07 KB