Commit aeeb5173 authored by Dave Airlie's avatar Dave Airlie
Browse files

Merge tag 'drm-intel-fixes-2021-05-27' of... 

Merge tag 'drm-intel-fixes-2021-05-27' of ssh://git.freedesktop.org/git/drm/drm-intel

 into drm-fixes

drm/i915 fixes for v5.13-rc4:
- Re-enable LTTPR non-transparent LT mode for DPCD_REV<1.4

Signed-off-by: default avatarDave Airlie <airlied@redhat.com>
From: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/875yz4bnmj.fsf@intel.com
parents b26389e8 e1185142

drivers/gpu/drm/i915/display/intel_dp_link_training.c

+33 −38
Original line number Diff line number Diff line
@@ -128,50 +128,14 @@ intel_dp_set_lttpr_transparent_mode(struct intel_dp *intel_dp, bool enable) 
	return drm_dp_dpcd_write(&intel_dp->aux, DP_PHY_REPEATER_MODE, &val, 1) == 1;

}



/**

 * intel_dp_init_lttpr_and_dprx_caps - detect LTTPR and DPRX caps, init the LTTPR link training mode

 * @intel_dp: Intel DP struct

 *

 * Read the LTTPR common and DPRX capabilities and switch to non-transparent

 * link training mode if any is detected and read the PHY capabilities for all

 * detected LTTPRs. In case of an LTTPR detection error or if the number of

 * LTTPRs is more than is supported (8), fall back to the no-LTTPR,

 * transparent mode link training mode.

 *

 * Returns:

 *   >0  if LTTPRs were detected and the non-transparent LT mode was set. The

 *       DPRX capabilities are read out.

 *    0  if no LTTPRs or more than 8 LTTPRs were detected or in case of a

 *       detection failure and the transparent LT mode was set. The DPRX

 *       capabilities are read out.

 *   <0  Reading out the DPRX capabilities failed.

 */

int intel_dp_init_lttpr_and_dprx_caps(struct intel_dp *intel_dp)

static int intel_dp_init_lttpr(struct intel_dp *intel_dp)

{

	int lttpr_count;

	bool ret;

	int i;



	ret = intel_dp_read_lttpr_common_caps(intel_dp);



	/* The DPTX shall read the DPRX caps after LTTPR detection. */

	if (drm_dp_read_dpcd_caps(&intel_dp->aux, intel_dp->dpcd)) {

		intel_dp_reset_lttpr_common_caps(intel_dp);

		return -EIO;

	}



	if (!ret)

	if (!intel_dp_read_lttpr_common_caps(intel_dp))

		return 0;



	/*

	 * The 0xF0000-0xF02FF range is only valid if the DPCD revision is

	 * at least 1.4.

	 */

	if (intel_dp->dpcd[DP_DPCD_REV] < 0x14) {

		intel_dp_reset_lttpr_common_caps(intel_dp);

		return 0;

	}



	lttpr_count = drm_dp_lttpr_count(intel_dp->lttpr_common_caps);

	/*

	 * Prevent setting LTTPR transparent mode explicitly if no LTTPRs are
@@ -211,6 +175,37 @@ int intel_dp_init_lttpr_and_dprx_caps(struct intel_dp *intel_dp) 


	return lttpr_count;

}



/**

 * intel_dp_init_lttpr_and_dprx_caps - detect LTTPR and DPRX caps, init the LTTPR link training mode

 * @intel_dp: Intel DP struct

 *

 * Read the LTTPR common and DPRX capabilities and switch to non-transparent

 * link training mode if any is detected and read the PHY capabilities for all

 * detected LTTPRs. In case of an LTTPR detection error or if the number of

 * LTTPRs is more than is supported (8), fall back to the no-LTTPR,

 * transparent mode link training mode.

 *

 * Returns:

 *   >0  if LTTPRs were detected and the non-transparent LT mode was set. The

 *       DPRX capabilities are read out.

 *    0  if no LTTPRs or more than 8 LTTPRs were detected or in case of a

 *       detection failure and the transparent LT mode was set. The DPRX

 *       capabilities are read out.

 *   <0  Reading out the DPRX capabilities failed.

 */

int intel_dp_init_lttpr_and_dprx_caps(struct intel_dp *intel_dp)

{

	int lttpr_count = intel_dp_init_lttpr(intel_dp);



	/* The DPTX shall read the DPRX caps after LTTPR detection. */

	if (drm_dp_read_dpcd_caps(&intel_dp->aux, intel_dp->dpcd)) {

		intel_dp_reset_lttpr_common_caps(intel_dp);

		return -EIO;

	}



	return lttpr_count;

}

EXPORT_SYMBOL(intel_dp_init_lttpr_and_dprx_caps);



static u8 dp_voltage_max(u8 preemph)