• Devarsh Thakkar's avatar
    arm64: dts: ti: k3-am62x-sk-common: Reserve 128MiB of global CMA · 9e856055
    Devarsh Thakkar authored
    Reserve 128MiB of global CMA which is also marked as re-usable
    so that OS can also use the same if peripheral drivers are not using the
    same.
    
    AM62x supports multimedia components such as GPU, dual Display and Camera.
    Assuming the worst-case scenario where all 3 are run in parallel below
    is the calculation :
    
    1) OV5640 camera sensor supports 1920x1080 resolution
    -> 1920 width x 1080 height x 2 bytesperpixel x 8 buffers
       (default in yavta) : 32MiB
    
    2) 1920x1200 Microtips LVDS panel supported
    -> 1920 width x 1080 height x 4 bytesperpixel x 2 buffers :
       16 MiB
    
    3) 1920x1080 HDMI display supported
    -> 1920 width x 1080 height x 4 bytesperpixel x 2 buffers :
       15.82 MiB which is ~16 MiB
    
    4) IMG GPU shares with display allocated buffers while rendering
       but in case some dedicated operation viz color conversion,
       keeping same window of ~16 MiB for GPU too.
    
    Total is 80 MiB and adding 32 MiB for other peripherals and extra
    16 MiB to keep as buffer for fragmentation thus rounding total to 128
    MiB.
    Signed-off-by: default avatarDevarsh Thakkar <devarsht@ti.com>
    Reviewed-by: default avatarRandolph Sapp <rs@ti.com>
    Link: https://lore.kernel.org/r/20240613150902.2173582-2-devarsht@ti.comSigned-off-by: default avatarVignesh Raghavendra <vigneshr@ti.com>
    9e856055
k3-am62x-sk-common.dtsi 13.3 KB