From: Ankit Nautiyal <[email protected]> Some BMG ultrajoiner configurations require support for Link M/N ratios between 10.0 and 15.0. This range is not natively supported and requires a workaround.
Wa_14021768792 enables this support by utilizing HDMI_EMP_DATA, CHICKEN_TRANS and the extended bits in the LINK_N register. Add the necessary logic to enable the workaround on applicable platforms. The underlying mechanism comes from the display C0, so it is gated on display stepping C0 and later. v2: -Don't include i915_drv.h and don't use struct drm_i915_private under display/. Use display->platform.battlemage, which names the affected platform directly, instead of IS_DGFX() combined with a display version check. (Jani) -Rebase on the reworked display WA framework, where the condition goes directly into the __intel_display_wa() switch. Bspec: 49266 Signed-off-by: Ankit Nautiyal <[email protected]> Co-developed-by: Suraj Kandpal <[email protected]> Signed-off-by: Suraj Kandpal <[email protected]> Reviewed-by: Mitul Golani <[email protected]> --- drivers/gpu/drm/i915/display/intel_display_wa.c | 9 +++++++++ drivers/gpu/drm/i915/display/intel_display_wa.h | 1 + 2 files changed, 10 insertions(+) diff --git a/drivers/gpu/drm/i915/display/intel_display_wa.c b/drivers/gpu/drm/i915/display/intel_display_wa.c index 91395076e903..e6f84dffdeb7 100644 --- a/drivers/gpu/drm/i915/display/intel_display_wa.c +++ b/drivers/gpu/drm/i915/display/intel_display_wa.c @@ -102,6 +102,15 @@ bool __intel_display_wa(struct intel_display *display, enum intel_display_wa wa, return DISPLAY_VERx100(display) == 3000 || DISPLAY_VERx100(display) == 2000 || DISPLAY_VERx100(display) == 1401; + /* + * Wa_14021768792: + * Fixes: Limitation of Link M/N ratio > 10 for specific Xe2HPD platforms. + * Workaround: Use HDMI_EMP_DATA, CHICKEN_BITs and extended bits in LINK_N + * registers to support LINK M/N ratios from > 10 but < 15. + */ + case INTEL_DISPLAY_WA_14021768792: + return display->platform.battlemage && + IS_DISPLAY_STEP(display, STEP_C0, STEP_FOREVER); case INTEL_DISPLAY_WA_14025769978: return DISPLAY_VER(display) == 35; case INTEL_DISPLAY_WA_14026643300: diff --git a/drivers/gpu/drm/i915/display/intel_display_wa.h b/drivers/gpu/drm/i915/display/intel_display_wa.h index f41e58d1d6e7..0b43c2144dcc 100644 --- a/drivers/gpu/drm/i915/display/intel_display_wa.h +++ b/drivers/gpu/drm/i915/display/intel_display_wa.h @@ -34,6 +34,7 @@ enum intel_display_wa { INTEL_DISPLAY_WA_14014191401, INTEL_DISPLAY_WA_14016740474, INTEL_DISPLAY_WA_14020863754, + INTEL_DISPLAY_WA_14021768792, INTEL_DISPLAY_WA_14025769978, INTEL_DISPLAY_WA_14026643300, INTEL_DISPLAY_WA_15013987218, -- 2.34.1
