Simplify intel_dp_max_data_rate() using drm_dp_bw_channel_coding_efficiency() to calculate the max data rate for both DP1.4 and UHBR link rates. This trades a redundant multiply/divide for readability.
Cc: Jani Nikula <[email protected]> Signed-off-by: Imre Deak <[email protected]> --- drivers/gpu/drm/i915/display/intel_dp.c | 26 ++++++++++++------------- 1 file changed, 12 insertions(+), 14 deletions(-) diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c index 209c27167e057..a93e8f6429d85 100644 --- a/drivers/gpu/drm/i915/display/intel_dp.c +++ b/drivers/gpu/drm/i915/display/intel_dp.c @@ -405,29 +405,27 @@ int intel_dp_effective_data_rate(int pixel_clock, int bpp_x16, int intel_dp_max_data_rate(int max_link_rate, int max_lanes) { - if (max_link_rate >= 1000000) { - /* - * UHBR rates always use 128b/132b channel encoding, and have - * 97.71% data bandwidth efficiency. Consider max_link_rate the - * link bit rate in units of 10000 bps. - */ - int max_link_rate_kbps = max_link_rate * 10; - - max_link_rate_kbps = DIV_ROUND_DOWN_ULL(mul_u32_u32(max_link_rate_kbps, 9671), 10000); - max_link_rate = max_link_rate_kbps / 8; - } + int ch_coding_efficiency = + drm_dp_bw_channel_coding_efficiency(drm_dp_is_uhbr_rate(max_link_rate)); + int max_link_rate_kbps = max_link_rate * 10; + /* + * UHBR rates always use 128b/132b channel encoding, and have + * 97.71% data bandwidth efficiency. Consider max_link_rate the + * link bit rate in units of 10000 bps. + */ /* * Lower than UHBR rates always use 8b/10b channel encoding, and have * 80% data bandwidth efficiency for SST non-FEC. However, this turns - * out to be a nop by coincidence, and can be skipped: + * out to be a nop by coincidence: * * int max_link_rate_kbps = max_link_rate * 10; * max_link_rate_kbps = DIV_ROUND_DOWN_ULL(max_link_rate_kbps * 8, 10); * max_link_rate = max_link_rate_kbps / 8; */ - - return max_link_rate * max_lanes; + return DIV_ROUND_DOWN_ULL(mul_u32_u32(max_link_rate_kbps * max_lanes, + ch_coding_efficiency), + 1000000 * 8); } bool intel_dp_can_bigjoiner(struct intel_dp *intel_dp) -- 2.39.2
