• Rodrigo Siqueira's avatar
    drm/amd/display: Add DC_FP helper to check FPU state · 0ea7ee82
    Rodrigo Siqueira authored
    To fully isolate FPU operations in a single place, we must avoid
    situations where compilers spill FP values to registers due to FP enable
    in a specific C file. Note that even if we isolate all FPU functions in
    a single file and call its interface from other files, the compiler
    might enable the use of FPU before we call DC_FP_START. Nevertheless, it
    is the programmer's responsibility to invoke DC_FP_START/END in the
    correct place. To highlight situations where developers forgot to use
    the FP protection before calling the DC FPU interface functions, we
    introduce a helper that checks if the function is invoked under FP
    protection. If not, it will trigger a kernel warning.
    
    Changes cince V3:
    - Rebase
    
    Changes cince V2 (Christian):
    - Do not use this_cpu_* between get/put_cpu_ptr().
    - In the kernel documentation, better describe restrictions.
    - Make dc_assert_fp_enabled trigger the ASSERT message.
    
    Changes since V1:
    - Remove fp_enable variables
    - Rename dc_is_fp_enabled to dc_assert_fp_enabled
    - Replace wrong variable type
    
    Cc: Harry Wentland <harry.wentland@amd.com>
    Cc: Anson Jacob <Anson.Jacob@amd.com>
    Cc: Christian König <christian.koenig@amd.com>
    Cc: Hersen Wu <hersenxs.wu@amd.com>
    Cc: Aric Cyr <aric.cyr@amd.com>
    Cc: Jun Lei <jun.lei@amd.com>
    Cc: Dmytro Laktyushkin <dmytro.laktyushkin@amd.com>
    Cc: Qingqing Zhuo <qingqing.zhuo@amd.com>
    Reported-by: default avatarkernel test robot <lkp@intel.com>
    Signed-off-by: default avatarRodrigo Siqueira <Rodrigo.Siqueira@amd.com>
    Reviewed-by: default avatarChristian König <christian.koenig@amd.com>
    Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
    0ea7ee82
dcn20_resource.c 124 KB