• Paul Walmsley's avatar
    ARM: 8334/1: amba: tegra-ahb: detect and correct bogus base address · ce7a10b0
    Paul Walmsley authored
    amba: tegra-ahb: detect and correct bogus base address
    
    From a hardware SoC integration point of view, the starting address of
    this IP block in the existing Tegra SoC DT files is off by 4 bytes
    from the actual base address.  Since we attempt to make old DT files
    forward-compatible with newer kernels, we cannot fix the IP block base
    address in old DT data. This patch works around the problem by
    detecting the four byte base address offset in the driver code, and
    correcting it if it's detected.  (In general, IP block base addresses
    almost always have a null low byte.)
    
    Future SoC DT data for Tegra AHB should use the correct Tegra AHB base
    address, in cases where there is no DT data backward compatibility
    requirement.
    
    This patch is a revision of the patch originally titled
    "amba: tegra-ahb: use correct base address for future chip support".
    This revision implements changes requested by Russell King:
    
    http://marc.info/?l=linux-tegra&m=142658851825062&w=2
    http://marc.info/?l=linux-tegra&m=142658873925178&w=2Signed-off-by: default avatarPaul Walmsley <paul@pwsan.com>
    Cc: Paul Walmsley <pwalmsley@nvidia.com>
    Cc: Alexandre Courbot <gnurou@gmail.com>
    Cc: Hiroshi DOYU <hdoyu@nvidia.com>
    Cc: Stephen Warren <swarren@wwwdotorg.org>
    Cc: Thierry Reding <thierry.reding@gmail.com>
    Cc: linux-kernel@vger.kernel.org
    Acked-by: default avatarStephen Warren <swarren@nvidia.com>
    Signed-off-by: default avatarRussell King <rmk+kernel@arm.linux.org.uk>
    ce7a10b0
tegra-ahb.c 8.08 KB