• Jesse Barnes's avatar
    drm/i915: FIFO watermark calculation fixes · dff33cfc
    Jesse Barnes authored
    I discovered several bugs in the FIFO code that was recently applied.
    Some of them fell into the "how did this ever work" category, since in
    some cases we were using the wrong FIFO size values, and the
    calculations ended up being way off.
    
    This patch fixes all the bugs I found, and works well on my GM45, 915GM
    and 855GM test machines; but as usual with these sorts of patches
    broader testing is definitely requested (in particular this patch
    affects 830, 845 and 865 for which I don't have test hardware).
    
    Overall, the patch clarifies the watermark calculation function by
    adding some comments and debug info, and making the variable names a
    bit clearer.  The "get FIFO size" portion of the code has also been
    corrected, so we should be able to properly detect the FIFO allocations
    for each pipe, for use in the watermark calculation.
    Signed-off-by: default avatarJesse Barnes <jbarnes@virtuousgeek.org>
    Signed-off-by: default avatarEric Anholt <eric@anholt.net>
    dff33cfc
intel_display.c 93.9 KB