Re: [PATCH v5 2/4] Revert "drm/tegra: Move drm_dp_link helpers to Tegra DRM"
From: Dmitry Osipenko
Date: Tue Dec 10 2019 - 14:14:45 EST
10.12.2019 08:53, allen ÐÐÑÐÑ:
> This reverts commit 9a42c7c647a9ad0f7ebb147a52eda3dcb7c84292.
Commit messsage must explain reason of the changes made in the patch.
> Signed-off-by: Allen Chen <allen.chen@xxxxxxxxxx>
> ---
> drivers/gpu/drm/drm_dp_helper.c | 128 ++++++
> drivers/gpu/drm/tegra/Makefile | 1 -
> drivers/gpu/drm/tegra/dp.c | 876 ----------------------------------------
> drivers/gpu/drm/tegra/dp.h | 177 --------
> drivers/gpu/drm/tegra/dpaux.c | 1 -
> drivers/gpu/drm/tegra/sor.c | 1 -
> include/drm/drm_dp_helper.h | 16 +
> 7 files changed, 144 insertions(+), 1056 deletions(-)
> delete mode 100644 drivers/gpu/drm/tegra/dp.c
> delete mode 100644 drivers/gpu/drm/tegra/dp.h
>
> diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c
> index 2c7870a..f567141 100644
> --- a/drivers/gpu/drm/drm_dp_helper.c
> +++ b/drivers/gpu/drm/drm_dp_helper.c
> @@ -352,6 +352,134 @@ int drm_dp_dpcd_read_link_status(struct drm_dp_aux *aux,
> EXPORT_SYMBOL(drm_dp_dpcd_read_link_status);
>
> /**
> + * drm_dp_link_probe() - probe a DisplayPort link for capabilities
> + * @aux: DisplayPort AUX channel
> + * @link: pointer to structure in which to return link capabilities
> + *
> + * The structure filled in by this function can usually be passed directly
> + * into drm_dp_link_power_up() and drm_dp_link_configure() to power up and
> + * configure the link based on the link's capabilities.
> + *
> + * Returns 0 on success or a negative error code on failure.
> + */
> +int drm_dp_link_probe(struct drm_dp_aux *aux, struct drm_dp_link *link)
> +{
> + u8 values[3];
> + int err;
> +
> + memset(link, 0, sizeof(*link));
> +
> + err = drm_dp_dpcd_read(aux, DP_DPCD_REV, values, sizeof(values));
> + if (err < 0)
> + return err;
> +
> + link->revision = values[0];
> + link->rate = drm_dp_bw_code_to_link_rate(values[1]);
> + link->num_lanes = values[2] & DP_MAX_LANE_COUNT_MASK;
> +
> + if (values[2] & DP_ENHANCED_FRAME_CAP)
> + link->capabilities |= DP_LINK_CAP_ENHANCED_FRAMING;
> +
> + return 0;
> +}
> +EXPORT_SYMBOL(drm_dp_link_probe);
> +
> +/**
> + * drm_dp_link_power_up() - power up a DisplayPort link
> + * @aux: DisplayPort AUX channel
> + * @link: pointer to a structure containing the link configuration
> + *
> + * Returns 0 on success or a negative error code on failure.
> + */
> +int drm_dp_link_power_up(struct drm_dp_aux *aux, struct drm_dp_link *link)
> +{
> + u8 value;
> + int err;
> +
> + /* DP_SET_POWER register is only available on DPCD v1.1 and later */
> + if (link->revision < 0x11)
> + return 0;
> +
> + err = drm_dp_dpcd_readb(aux, DP_SET_POWER, &value);
> + if (err < 0)
> + return err;
> +
> + value &= ~DP_SET_POWER_MASK;
> + value |= DP_SET_POWER_D0;
> +
> + err = drm_dp_dpcd_writeb(aux, DP_SET_POWER, value);
> + if (err < 0)
> + return err;
> +
> + /*
> + * According to the DP 1.1 specification, a "Sink Device must exit the
> + * power saving state within 1 ms" (Section 2.5.3.1, Table 5-52, "Sink
> + * Control Field" (register 0x600).
> + */
> + usleep_range(1000, 2000);
> +
> + return 0;
> +}
> +EXPORT_SYMBOL(drm_dp_link_power_up);
> +
> +/**
> + * drm_dp_link_power_down() - power down a DisplayPort link
> + * @aux: DisplayPort AUX channel
> + * @link: pointer to a structure containing the link configuration
> + *
> + * Returns 0 on success or a negative error code on failure.
> + */
> +int drm_dp_link_power_down(struct drm_dp_aux *aux, struct drm_dp_link *link)
> +{
> + u8 value;
> + int err;
> +
> + /* DP_SET_POWER register is only available on DPCD v1.1 and later */
> + if (link->revision < 0x11)
> + return 0;
> +
> + err = drm_dp_dpcd_readb(aux, DP_SET_POWER, &value);
> + if (err < 0)
> + return err;
> +
> + value &= ~DP_SET_POWER_MASK;
> + value |= DP_SET_POWER_D3;
> +
> + err = drm_dp_dpcd_writeb(aux, DP_SET_POWER, value);
> + if (err < 0)
> + return err;
> +
> + return 0;
> +}
> +EXPORT_SYMBOL(drm_dp_link_power_down);
> +
> +/**
> + * drm_dp_link_configure() - configure a DisplayPort link
> + * @aux: DisplayPort AUX channel
> + * @link: pointer to a structure containing the link configuration
> + *
> + * Returns 0 on success or a negative error code on failure.
> + */
> +int drm_dp_link_configure(struct drm_dp_aux *aux, struct drm_dp_link *link)
> +{
> + u8 values[2];
> + int err;
> +
> + values[0] = drm_dp_link_rate_to_bw_code(link->rate);
> + values[1] = link->num_lanes;
> +
> + if (link->capabilities & DP_LINK_CAP_ENHANCED_FRAMING)
> + values[1] |= DP_LANE_COUNT_ENHANCED_FRAME_EN;
> +
> + err = drm_dp_dpcd_write(aux, DP_LINK_BW_SET, values, sizeof(values));
> + if (err < 0)
> + return err;
> +
> + return 0;
> +}
> +EXPORT_SYMBOL(drm_dp_link_configure);
> +
> +/**
> * drm_dp_downstream_max_clock() - extract branch device max
> * pixel rate for legacy VGA
> * converter or max TMDS clock
> diff --git a/drivers/gpu/drm/tegra/Makefile b/drivers/gpu/drm/tegra/Makefile
> index d6cf202..33c463e 100644
> --- a/drivers/gpu/drm/tegra/Makefile
> +++ b/drivers/gpu/drm/tegra/Makefile
> @@ -5,7 +5,6 @@ tegra-drm-y := \
> drm.o \
> gem.o \
> fb.o \
> - dp.o \
> hub.o \
> plane.o \
> dc.o \
> diff --git a/drivers/gpu/drm/tegra/dp.c b/drivers/gpu/drm/tegra/dp.c
> deleted file mode 100644
> index 70dfb7d..00000000
> --- a/drivers/gpu/drm/tegra/dp.c
> +++ /dev/null
> @@ -1,876 +0,0 @@
> -// SPDX-License-Identifier: MIT
> -/*
> - * Copyright (C) 2013-2019 NVIDIA Corporation
> - * Copyright (C) 2015 Rob Clark
> - */
> -
> -#include <drm/drm_crtc.h>
> -#include <drm/drm_dp_helper.h>
> -#include <drm/drm_print.h>
> -
> -#include "dp.h"
> -
> -static const u8 drm_dp_edp_revisions[] = { 0x11, 0x12, 0x13, 0x14 };
> -
> -static void drm_dp_link_caps_reset(struct drm_dp_link_caps *caps)
> -{
> - caps->enhanced_framing = false;
> - caps->tps3_supported = false;
> - caps->fast_training = false;
> - caps->channel_coding = false;
> - caps->alternate_scrambler_reset = false;
> -}
> -
> -void drm_dp_link_caps_copy(struct drm_dp_link_caps *dest,
> - const struct drm_dp_link_caps *src)
> -{
> - dest->enhanced_framing = src->enhanced_framing;
> - dest->tps3_supported = src->tps3_supported;
> - dest->fast_training = src->fast_training;
> - dest->channel_coding = src->channel_coding;
> - dest->alternate_scrambler_reset = src->alternate_scrambler_reset;
> -}
> -
> -static void drm_dp_link_reset(struct drm_dp_link *link)
> -{
> - unsigned int i;
> -
> - if (!link)
> - return;
> -
> - link->revision = 0;
> - link->max_rate = 0;
> - link->max_lanes = 0;
> -
> - drm_dp_link_caps_reset(&link->caps);
> - link->aux_rd_interval.cr = 0;
> - link->aux_rd_interval.ce = 0;
> - link->edp = 0;
> -
> - link->rate = 0;
> - link->lanes = 0;
> -
> - for (i = 0; i < DP_MAX_SUPPORTED_RATES; i++)
> - link->rates[i] = 0;
> -
> - link->num_rates = 0;
> -}
> -
> -/**
> - * drm_dp_link_add_rate() - add a rate to the list of supported rates
> - * @link: the link to add the rate to
> - * @rate: the rate to add
> - *
> - * Add a link rate to the list of supported link rates.
> - *
> - * Returns:
> - * 0 on success or one of the following negative error codes on failure:
> - * - ENOSPC if the maximum number of supported rates has been reached
> - * - EEXISTS if the link already supports this rate
> - *
> - * See also:
> - * drm_dp_link_remove_rate()
> - */
> -int drm_dp_link_add_rate(struct drm_dp_link *link, unsigned long rate)
> -{
> - unsigned int i, pivot;
> -
> - if (link->num_rates == DP_MAX_SUPPORTED_RATES)
> - return -ENOSPC;
> -
> - for (pivot = 0; pivot < link->num_rates; pivot++)
> - if (rate <= link->rates[pivot])
> - break;
> -
> - if (pivot != link->num_rates && rate == link->rates[pivot])
> - return -EEXIST;
> -
> - for (i = link->num_rates; i > pivot; i--)
> - link->rates[i] = link->rates[i - 1];
> -
> - link->rates[pivot] = rate;
> - link->num_rates++;
> -
> - return 0;
> -}
> -
> -/**
> - * drm_dp_link_remove_rate() - remove a rate from the list of supported rates
> - * @link: the link from which to remove the rate
> - * @rate: the rate to remove
> - *
> - * Removes a link rate from the list of supported link rates.
> - *
> - * Returns:
> - * 0 on success or one of the following negative error codes on failure:
> - * - EINVAL if the specified rate is not among the supported rates
> - *
> - * See also:
> - * drm_dp_link_add_rate()
> - */
> -int drm_dp_link_remove_rate(struct drm_dp_link *link, unsigned long rate)
> -{
> - unsigned int i;
> -
> - for (i = 0; i < link->num_rates; i++)
> - if (rate == link->rates[i])
> - break;
> -
> - if (i == link->num_rates)
> - return -EINVAL;
> -
> - link->num_rates--;
> -
> - while (i < link->num_rates) {
> - link->rates[i] = link->rates[i + 1];
> - i++;
> - }
> -
> - return 0;
> -}
> -
> -/**
> - * drm_dp_link_update_rates() - normalize the supported link rates array
> - * @link: the link for which to normalize the supported link rates
> - *
> - * Users should call this function after they've manually modified the array
> - * of supported link rates. This function removes any stale entries, compacts
> - * the array and updates the supported link rate count. Note that calling the
> - * drm_dp_link_remove_rate() function already does this janitorial work.
> - *
> - * See also:
> - * drm_dp_link_add_rate(), drm_dp_link_remove_rate()
> - */
> -void drm_dp_link_update_rates(struct drm_dp_link *link)
> -{
> - unsigned int i, count = 0;
> -
> - for (i = 0; i < link->num_rates; i++) {
> - if (link->rates[i] != 0)
> - link->rates[count++] = link->rates[i];
> - }
> -
> - for (i = count; i < link->num_rates; i++)
> - link->rates[i] = 0;
> -
> - link->num_rates = count;
> -}
> -
> -/**
> - * drm_dp_link_probe() - probe a DisplayPort link for capabilities
> - * @aux: DisplayPort AUX channel
> - * @link: pointer to structure in which to return link capabilities
> - *
> - * The structure filled in by this function can usually be passed directly
> - * into drm_dp_link_power_up() and drm_dp_link_configure() to power up and
> - * configure the link based on the link's capabilities.
> - *
> - * Returns 0 on success or a negative error code on failure.
> - */
> -int drm_dp_link_probe(struct drm_dp_aux *aux, struct drm_dp_link *link)
> -{
> - u8 dpcd[DP_RECEIVER_CAP_SIZE], value;
> - unsigned int rd_interval;
> - int err;
> -
> - drm_dp_link_reset(link);
> -
> - err = drm_dp_dpcd_read(aux, DP_DPCD_REV, dpcd, sizeof(dpcd));
> - if (err < 0)
> - return err;
> -
> - link->revision = dpcd[DP_DPCD_REV];
> - link->max_rate = drm_dp_max_link_rate(dpcd);
> - link->max_lanes = drm_dp_max_lane_count(dpcd);
> -
> - link->caps.enhanced_framing = drm_dp_enhanced_frame_cap(dpcd);
> - link->caps.tps3_supported = drm_dp_tps3_supported(dpcd);
> - link->caps.fast_training = drm_dp_fast_training_cap(dpcd);
> - link->caps.channel_coding = drm_dp_channel_coding_supported(dpcd);
> -
> - if (drm_dp_alternate_scrambler_reset_cap(dpcd)) {
> - link->caps.alternate_scrambler_reset = true;
> -
> - err = drm_dp_dpcd_readb(aux, DP_EDP_DPCD_REV, &value);
> - if (err < 0)
> - return err;
> -
> - if (value >= ARRAY_SIZE(drm_dp_edp_revisions))
> - DRM_ERROR("unsupported eDP version: %02x\n", value);
> - else
> - link->edp = drm_dp_edp_revisions[value];
> - }
> -
> - /*
> - * The DPCD stores the AUX read interval in units of 4 ms. There are
> - * two special cases:
> - *
> - * 1) if the TRAINING_AUX_RD_INTERVAL field is 0, the clock recovery
> - * and channel equalization should use 100 us or 400 us AUX read
> - * intervals, respectively
> - *
> - * 2) for DP v1.4 and above, clock recovery should always use 100 us
> - * AUX read intervals
> - */
> - rd_interval = dpcd[DP_TRAINING_AUX_RD_INTERVAL] &
> - DP_TRAINING_AUX_RD_MASK;
> -
> - if (rd_interval > 4) {
> - DRM_DEBUG_KMS("AUX interval %u out of range (max. 4)\n",
> - rd_interval);
> - rd_interval = 4;
> - }
> -
> - rd_interval *= 4 * USEC_PER_MSEC;
> -
> - if (rd_interval == 0 || link->revision >= DP_DPCD_REV_14)
> - link->aux_rd_interval.cr = 100;
> -
> - if (rd_interval == 0)
> - link->aux_rd_interval.ce = 400;
> -
> - link->rate = link->max_rate;
> - link->lanes = link->max_lanes;
> -
> - /* Parse SUPPORTED_LINK_RATES from eDP 1.4 */
> - if (link->edp >= 0x14) {
> - u8 supported_rates[DP_MAX_SUPPORTED_RATES * 2];
> - unsigned int i;
> - u16 rate;
> -
> - err = drm_dp_dpcd_read(aux, DP_SUPPORTED_LINK_RATES,
> - supported_rates,
> - sizeof(supported_rates));
> - if (err < 0)
> - return err;
> -
> - for (i = 0; i < DP_MAX_SUPPORTED_RATES; i++) {
> - rate = supported_rates[i * 2 + 1] << 8 |
> - supported_rates[i * 2 + 0];
> -
> - drm_dp_link_add_rate(link, rate * 200);
> - }
> - }
> -
> - return 0;
> -}
> -
> -/**
> - * drm_dp_link_power_up() - power up a DisplayPort link
> - * @aux: DisplayPort AUX channel
> - * @link: pointer to a structure containing the link configuration
> - *
> - * Returns 0 on success or a negative error code on failure.
> - */
> -int drm_dp_link_power_up(struct drm_dp_aux *aux, struct drm_dp_link *link)
> -{
> - u8 value;
> - int err;
> -
> - /* DP_SET_POWER register is only available on DPCD v1.1 and later */
> - if (link->revision < 0x11)
> - return 0;
> -
> - err = drm_dp_dpcd_readb(aux, DP_SET_POWER, &value);
> - if (err < 0)
> - return err;
> -
> - value &= ~DP_SET_POWER_MASK;
> - value |= DP_SET_POWER_D0;
> -
> - err = drm_dp_dpcd_writeb(aux, DP_SET_POWER, value);
> - if (err < 0)
> - return err;
> -
> - /*
> - * According to the DP 1.1 specification, a "Sink Device must exit the
> - * power saving state within 1 ms" (Section 2.5.3.1, Table 5-52, "Sink
> - * Control Field" (register 0x600).
> - */
> - usleep_range(1000, 2000);
> -
> - return 0;
> -}
> -
> -/**
> - * drm_dp_link_power_down() - power down a DisplayPort link
> - * @aux: DisplayPort AUX channel
> - * @link: pointer to a structure containing the link configuration
> - *
> - * Returns 0 on success or a negative error code on failure.
> - */
> -int drm_dp_link_power_down(struct drm_dp_aux *aux, struct drm_dp_link *link)
> -{
> - u8 value;
> - int err;
> -
> - /* DP_SET_POWER register is only available on DPCD v1.1 and later */
> - if (link->revision < 0x11)
> - return 0;
> -
> - err = drm_dp_dpcd_readb(aux, DP_SET_POWER, &value);
> - if (err < 0)
> - return err;
> -
> - value &= ~DP_SET_POWER_MASK;
> - value |= DP_SET_POWER_D3;
> -
> - err = drm_dp_dpcd_writeb(aux, DP_SET_POWER, value);
> - if (err < 0)
> - return err;
> -
> - return 0;
> -}
> -
> -/**
> - * drm_dp_link_configure() - configure a DisplayPort link
> - * @aux: DisplayPort AUX channel
> - * @link: pointer to a structure containing the link configuration
> - *
> - * Returns 0 on success or a negative error code on failure.
> - */
> -int drm_dp_link_configure(struct drm_dp_aux *aux, struct drm_dp_link *link)
> -{
> - u8 values[2], value;
> - int err;
> -
> - if (link->ops && link->ops->configure) {
> - err = link->ops->configure(link);
> - if (err < 0) {
> - DRM_ERROR("failed to configure DP link: %d\n", err);
> - return err;
> - }
> - }
> -
> - values[0] = drm_dp_link_rate_to_bw_code(link->rate);
> - values[1] = link->lanes;
> -
> - if (link->caps.enhanced_framing)
> - values[1] |= DP_LANE_COUNT_ENHANCED_FRAME_EN;
> -
> - err = drm_dp_dpcd_write(aux, DP_LINK_BW_SET, values, sizeof(values));
> - if (err < 0)
> - return err;
> -
> - if (link->caps.channel_coding)
> - value = DP_SET_ANSI_8B10B;
> - else
> - value = 0;
> -
> - err = drm_dp_dpcd_writeb(aux, DP_MAIN_LINK_CHANNEL_CODING_SET, value);
> - if (err < 0)
> - return err;
> -
> - if (link->caps.alternate_scrambler_reset) {
> - err = drm_dp_dpcd_writeb(aux, DP_EDP_CONFIGURATION_SET,
> - DP_ALTERNATE_SCRAMBLER_RESET_ENABLE);
> - if (err < 0)
> - return err;
> - }
> -
> - return 0;
> -}
> -
> -/**
> - * drm_dp_link_choose() - choose the lowest possible configuration for a mode
> - * @link: DRM DP link object
> - * @mode: DRM display mode
> - * @info: DRM display information
> - *
> - * According to the eDP specification, a source should select a configuration
> - * with the lowest number of lanes and the lowest possible link rate that can
> - * match the bitrate requirements of a video mode. However it must ensure not
> - * to exceed the capabilities of the sink.
> - *
> - * Returns: 0 on success or a negative error code on failure.
> - */
> -int drm_dp_link_choose(struct drm_dp_link *link,
> - const struct drm_display_mode *mode,
> - const struct drm_display_info *info)
> -{
> - /* available link symbol clock rates */
> - static const unsigned int rates[3] = { 162000, 270000, 540000 };
> - /* available number of lanes */
> - static const unsigned int lanes[3] = { 1, 2, 4 };
> - unsigned long requirement, capacity;
> - unsigned int rate = link->max_rate;
> - unsigned int i, j;
> -
> - /* bandwidth requirement */
> - requirement = mode->clock * info->bpc * 3;
> -
> - for (i = 0; i < ARRAY_SIZE(lanes) && lanes[i] <= link->max_lanes; i++) {
> - for (j = 0; j < ARRAY_SIZE(rates) && rates[j] <= rate; j++) {
> - /*
> - * Capacity for this combination of lanes and rate,
> - * factoring in the ANSI 8B/10B encoding.
> - *
> - * Link rates in the DRM DP helpers are really link
> - * symbol frequencies, so a tenth of the actual rate
> - * of the link.
> - */
> - capacity = lanes[i] * (rates[j] * 10) * 8 / 10;
> -
> - if (capacity >= requirement) {
> - DRM_DEBUG_KMS("using %u lanes at %u kHz (%lu/%lu kbps)\n",
> - lanes[i], rates[j], requirement,
> - capacity);
> - link->lanes = lanes[i];
> - link->rate = rates[j];
> - return 0;
> - }
> - }
> - }
> -
> - return -ERANGE;
> -}
> -
> -/**
> - * DOC: Link training
> - *
> - * These functions contain common logic and helpers to implement DisplayPort
> - * link training.
> - */
> -
> -/**
> - * drm_dp_link_train_init() - initialize DisplayPort link training state
> - * @train: DisplayPort link training state
> - */
> -void drm_dp_link_train_init(struct drm_dp_link_train *train)
> -{
> - struct drm_dp_link_train_set *request = &train->request;
> - struct drm_dp_link_train_set *adjust = &train->adjust;
> - unsigned int i;
> -
> - for (i = 0; i < 4; i++) {
> - request->voltage_swing[i] = 0;
> - adjust->voltage_swing[i] = 0;
> -
> - request->pre_emphasis[i] = 0;
> - adjust->pre_emphasis[i] = 0;
> -
> - request->post_cursor[i] = 0;
> - adjust->post_cursor[i] = 0;
> - }
> -
> - train->pattern = DP_TRAINING_PATTERN_DISABLE;
> - train->clock_recovered = false;
> - train->channel_equalized = false;
> -}
> -
> -static bool drm_dp_link_train_valid(const struct drm_dp_link_train *train)
> -{
> - return train->clock_recovered && train->channel_equalized;
> -}
> -
> -static int drm_dp_link_apply_training(struct drm_dp_link *link)
> -{
> - struct drm_dp_link_train_set *request = &link->train.request;
> - unsigned int lanes = link->lanes, *vs, *pe, *pc, i;
> - struct drm_dp_aux *aux = link->aux;
> - u8 values[4], pattern = 0;
> - int err;
> -
> - err = link->ops->apply_training(link);
> - if (err < 0) {
> - DRM_ERROR("failed to apply link training: %d\n", err);
> - return err;
> - }
> -
> - vs = request->voltage_swing;
> - pe = request->pre_emphasis;
> - pc = request->post_cursor;
> -
> - /* write currently selected voltage-swing and pre-emphasis levels */
> - for (i = 0; i < lanes; i++)
> - values[i] = DP_TRAIN_VOLTAGE_SWING_LEVEL(vs[i]) |
> - DP_TRAIN_PRE_EMPHASIS_LEVEL(pe[i]);
> -
> - err = drm_dp_dpcd_write(aux, DP_TRAINING_LANE0_SET, values, lanes);
> - if (err < 0) {
> - DRM_ERROR("failed to set training parameters: %d\n", err);
> - return err;
> - }
> -
> - /* write currently selected post-cursor level (if supported) */
> - if (link->revision >= 0x12 && link->rate == 540000) {
> - values[0] = values[1] = 0;
> -
> - for (i = 0; i < lanes; i++)
> - values[i / 2] |= DP_LANE_POST_CURSOR(i, pc[i]);
> -
> - err = drm_dp_dpcd_write(aux, DP_TRAINING_LANE0_1_SET2, values,
> - DIV_ROUND_UP(lanes, 2));
> - if (err < 0) {
> - DRM_ERROR("failed to set post-cursor: %d\n", err);
> - return err;
> - }
> - }
> -
> - /* write link pattern */
> - if (link->train.pattern != DP_TRAINING_PATTERN_DISABLE)
> - pattern |= DP_LINK_SCRAMBLING_DISABLE;
> -
> - pattern |= link->train.pattern;
> -
> - err = drm_dp_dpcd_writeb(aux, DP_TRAINING_PATTERN_SET, pattern);
> - if (err < 0) {
> - DRM_ERROR("failed to set training pattern: %d\n", err);
> - return err;
> - }
> -
> - return 0;
> -}
> -
> -static void drm_dp_link_train_wait(struct drm_dp_link *link)
> -{
> - unsigned long min = 0;
> -
> - switch (link->train.pattern) {
> - case DP_TRAINING_PATTERN_1:
> - min = link->aux_rd_interval.cr;
> - break;
> -
> - case DP_TRAINING_PATTERN_2:
> - case DP_TRAINING_PATTERN_3:
> - min = link->aux_rd_interval.ce;
> - break;
> -
> - default:
> - break;
> - }
> -
> - if (min > 0)
> - usleep_range(min, 2 * min);
> -}
> -
> -static void drm_dp_link_get_adjustments(struct drm_dp_link *link,
> - u8 status[DP_LINK_STATUS_SIZE])
> -{
> - struct drm_dp_link_train_set *adjust = &link->train.adjust;
> - unsigned int i;
> -
> - for (i = 0; i < link->lanes; i++) {
> - adjust->voltage_swing[i] =
> - drm_dp_get_adjust_request_voltage(status, i) >>
> - DP_TRAIN_VOLTAGE_SWING_SHIFT;
> -
> - adjust->pre_emphasis[i] =
> - drm_dp_get_adjust_request_pre_emphasis(status, i) >>
> - DP_TRAIN_PRE_EMPHASIS_SHIFT;
> -
> - adjust->post_cursor[i] =
> - drm_dp_get_adjust_request_post_cursor(status, i);
> - }
> -}
> -
> -static void drm_dp_link_train_adjust(struct drm_dp_link_train *train)
> -{
> - struct drm_dp_link_train_set *request = &train->request;
> - struct drm_dp_link_train_set *adjust = &train->adjust;
> - unsigned int i;
> -
> - for (i = 0; i < 4; i++)
> - if (request->voltage_swing[i] != adjust->voltage_swing[i])
> - request->voltage_swing[i] = adjust->voltage_swing[i];
> -
> - for (i = 0; i < 4; i++)
> - if (request->pre_emphasis[i] != adjust->pre_emphasis[i])
> - request->pre_emphasis[i] = adjust->pre_emphasis[i];
> -
> - for (i = 0; i < 4; i++)
> - if (request->post_cursor[i] != adjust->post_cursor[i])
> - request->post_cursor[i] = adjust->post_cursor[i];
> -}
> -
> -static int drm_dp_link_recover_clock(struct drm_dp_link *link)
> -{
> - u8 status[DP_LINK_STATUS_SIZE];
> - int err;
> -
> - err = drm_dp_link_apply_training(link);
> - if (err < 0)
> - return err;
> -
> - drm_dp_link_train_wait(link);
> -
> - err = drm_dp_dpcd_read_link_status(link->aux, status);
> - if (err < 0) {
> - DRM_ERROR("failed to read link status: %d\n", err);
> - return err;
> - }
> -
> - if (!drm_dp_clock_recovery_ok(status, link->lanes))
> - drm_dp_link_get_adjustments(link, status);
> - else
> - link->train.clock_recovered = true;
> -
> - return 0;
> -}
> -
> -static int drm_dp_link_clock_recovery(struct drm_dp_link *link)
> -{
> - unsigned int repeat;
> - int err;
> -
> - /* start clock recovery using training pattern 1 */
> - link->train.pattern = DP_TRAINING_PATTERN_1;
> -
> - for (repeat = 1; repeat < 5; repeat++) {
> - err = drm_dp_link_recover_clock(link);
> - if (err < 0) {
> - DRM_ERROR("failed to recover clock: %d\n", err);
> - return err;
> - }
> -
> - if (link->train.clock_recovered)
> - break;
> -
> - drm_dp_link_train_adjust(&link->train);
> - }
> -
> - return 0;
> -}
> -
> -static int drm_dp_link_equalize_channel(struct drm_dp_link *link)
> -{
> - struct drm_dp_aux *aux = link->aux;
> - u8 status[DP_LINK_STATUS_SIZE];
> - int err;
> -
> - err = drm_dp_link_apply_training(link);
> - if (err < 0)
> - return err;
> -
> - drm_dp_link_train_wait(link);
> -
> - err = drm_dp_dpcd_read_link_status(aux, status);
> - if (err < 0) {
> - DRM_ERROR("failed to read link status: %d\n", err);
> - return err;
> - }
> -
> - if (!drm_dp_clock_recovery_ok(status, link->lanes)) {
> - DRM_ERROR("clock recovery lost while equalizing channel\n");
> - link->train.clock_recovered = false;
> - return 0;
> - }
> -
> - if (!drm_dp_channel_eq_ok(status, link->lanes))
> - drm_dp_link_get_adjustments(link, status);
> - else
> - link->train.channel_equalized = true;
> -
> - return 0;
> -}
> -
> -static int drm_dp_link_channel_equalization(struct drm_dp_link *link)
> -{
> - unsigned int repeat;
> - int err;
> -
> - /* start channel equalization using pattern 2 or 3 */
> - if (link->caps.tps3_supported)
> - link->train.pattern = DP_TRAINING_PATTERN_3;
> - else
> - link->train.pattern = DP_TRAINING_PATTERN_2;
> -
> - for (repeat = 1; repeat < 5; repeat++) {
> - err = drm_dp_link_equalize_channel(link);
> - if (err < 0) {
> - DRM_ERROR("failed to equalize channel: %d\n", err);
> - return err;
> - }
> -
> - if (link->train.channel_equalized)
> - break;
> -
> - drm_dp_link_train_adjust(&link->train);
> - }
> -
> - return 0;
> -}
> -
> -static int drm_dp_link_downgrade(struct drm_dp_link *link)
> -{
> - switch (link->rate) {
> - case 162000:
> - return -EINVAL;
> -
> - case 270000:
> - link->rate = 162000;
> - break;
> -
> - case 540000:
> - link->rate = 270000;
> - return 0;
> - }
> -
> - return 0;
> -}
> -
> -static void drm_dp_link_train_disable(struct drm_dp_link *link)
> -{
> - int err;
> -
> - link->train.pattern = DP_TRAINING_PATTERN_DISABLE;
> -
> - err = drm_dp_link_apply_training(link);
> - if (err < 0)
> - DRM_ERROR("failed to disable link training: %d\n", err);
> -}
> -
> -static int drm_dp_link_train_full(struct drm_dp_link *link)
> -{
> - int err;
> -
> -retry:
> - DRM_DEBUG_KMS("full-training link: %u lane%s at %u MHz\n",
> - link->lanes, (link->lanes > 1) ? "s" : "",
> - link->rate / 100);
> -
> - err = drm_dp_link_configure(link->aux, link);
> - if (err < 0) {
> - DRM_ERROR("failed to configure DP link: %d\n", err);
> - return err;
> - }
> -
> - err = drm_dp_link_clock_recovery(link);
> - if (err < 0) {
> - DRM_ERROR("clock recovery failed: %d\n", err);
> - goto out;
> - }
> -
> - if (!link->train.clock_recovered) {
> - DRM_ERROR("clock recovery failed, downgrading link\n");
> -
> - err = drm_dp_link_downgrade(link);
> - if (err < 0)
> - goto out;
> -
> - goto retry;
> - }
> -
> - DRM_DEBUG_KMS("clock recovery succeeded\n");
> -
> - err = drm_dp_link_channel_equalization(link);
> - if (err < 0) {
> - DRM_ERROR("channel equalization failed: %d\n", err);
> - goto out;
> - }
> -
> - if (!link->train.channel_equalized) {
> - DRM_ERROR("channel equalization failed, downgrading link\n");
> -
> - err = drm_dp_link_downgrade(link);
> - if (err < 0)
> - goto out;
> -
> - goto retry;
> - }
> -
> - DRM_DEBUG_KMS("channel equalization succeeded\n");
> -
> -out:
> - drm_dp_link_train_disable(link);
> - return err;
> -}
> -
> -static int drm_dp_link_train_fast(struct drm_dp_link *link)
> -{
> - u8 status[DP_LINK_STATUS_SIZE];
> - int err;
> -
> - DRM_DEBUG_KMS("fast-training link: %u lane%s at %u MHz\n",
> - link->lanes, (link->lanes > 1) ? "s" : "",
> - link->rate / 100);
> -
> - err = drm_dp_link_configure(link->aux, link);
> - if (err < 0) {
> - DRM_ERROR("failed to configure DP link: %d\n", err);
> - return err;
> - }
> -
> - /* transmit training pattern 1 for 500 microseconds */
> - link->train.pattern = DP_TRAINING_PATTERN_1;
> -
> - err = drm_dp_link_apply_training(link);
> - if (err < 0)
> - goto out;
> -
> - usleep_range(500, 1000);
> -
> - /* transmit training pattern 2 or 3 for 500 microseconds */
> - if (link->caps.tps3_supported)
> - link->train.pattern = DP_TRAINING_PATTERN_3;
> - else
> - link->train.pattern = DP_TRAINING_PATTERN_2;
> -
> - err = drm_dp_link_apply_training(link);
> - if (err < 0)
> - goto out;
> -
> - usleep_range(500, 1000);
> -
> - err = drm_dp_dpcd_read_link_status(link->aux, status);
> - if (err < 0) {
> - DRM_ERROR("failed to read link status: %d\n", err);
> - goto out;
> - }
> -
> - if (!drm_dp_clock_recovery_ok(status, link->lanes)) {
> - DRM_ERROR("clock recovery failed\n");
> - err = -EIO;
> - }
> -
> - if (!drm_dp_channel_eq_ok(status, link->lanes)) {
> - DRM_ERROR("channel equalization failed\n");
> - err = -EIO;
> - }
> -
> -out:
> - drm_dp_link_train_disable(link);
> - return err;
> -}
> -
> -/**
> - * drm_dp_link_train() - perform DisplayPort link training
> - * @link: a DP link object
> - *
> - * Uses the context stored in the DP link object to perform link training. It
> - * is expected that drivers will call drm_dp_link_probe() to obtain the link
> - * capabilities before performing link training.
> - *
> - * If the sink supports fast link training (no AUX CH handshake) and valid
> - * training settings are available, this function will try to perform fast
> - * link training and fall back to full link training on failure.
> - *
> - * Returns: 0 on success or a negative error code on failure.
> - */
> -int drm_dp_link_train(struct drm_dp_link *link)
> -{
> - int err;
> -
> - drm_dp_link_train_init(&link->train);
> -
> - if (link->caps.fast_training) {
> - if (drm_dp_link_train_valid(&link->train)) {
> - err = drm_dp_link_train_fast(link);
> - if (err < 0)
> - DRM_ERROR("fast link training failed: %d\n",
> - err);
> - else
> - return 0;
> - } else {
> - DRM_DEBUG_KMS("training parameters not available\n");
> - }
> - } else {
> - DRM_DEBUG_KMS("fast link training not supported\n");
> - }
> -
> - err = drm_dp_link_train_full(link);
> - if (err < 0)
> - DRM_ERROR("full link training failed: %d\n", err);
> -
> - return err;
> -}
> diff --git a/drivers/gpu/drm/tegra/dp.h b/drivers/gpu/drm/tegra/dp.h
> deleted file mode 100644
> index cb12ed0..00000000
> --- a/drivers/gpu/drm/tegra/dp.h
> +++ /dev/null
> @@ -1,177 +0,0 @@
> -/* SPDX-License-Identifier: MIT */
> -/*
> - * Copyright (C) 2013-2019 NVIDIA Corporation.
> - * Copyright (C) 2015 Rob Clark
> - */
> -
> -#ifndef DRM_TEGRA_DP_H
> -#define DRM_TEGRA_DP_H 1
> -
> -#include <linux/types.h>
> -
> -struct drm_display_info;
> -struct drm_display_mode;
> -struct drm_dp_aux;
> -struct drm_dp_link;
> -
> -/**
> - * struct drm_dp_link_caps - DP link capabilities
> - */
> -struct drm_dp_link_caps {
> - /**
> - * @enhanced_framing:
> - *
> - * enhanced framing capability (mandatory as of DP 1.2)
> - */
> - bool enhanced_framing;
> -
> - /**
> - * tps3_supported:
> - *
> - * training pattern sequence 3 supported for equalization
> - */
> - bool tps3_supported;
> -
> - /**
> - * @fast_training:
> - *
> - * AUX CH handshake not required for link training
> - */
> - bool fast_training;
> -
> - /**
> - * @channel_coding:
> - *
> - * ANSI 8B/10B channel coding capability
> - */
> - bool channel_coding;
> -
> - /**
> - * @alternate_scrambler_reset:
> - *
> - * eDP alternate scrambler reset capability
> - */
> - bool alternate_scrambler_reset;
> -};
> -
> -void drm_dp_link_caps_copy(struct drm_dp_link_caps *dest,
> - const struct drm_dp_link_caps *src);
> -
> -/**
> - * struct drm_dp_link_ops - DP link operations
> - */
> -struct drm_dp_link_ops {
> - /**
> - * @apply_training:
> - */
> - int (*apply_training)(struct drm_dp_link *link);
> -
> - /**
> - * @configure:
> - */
> - int (*configure)(struct drm_dp_link *link);
> -};
> -
> -#define DP_TRAIN_VOLTAGE_SWING_LEVEL(x) ((x) << 0)
> -#define DP_TRAIN_PRE_EMPHASIS_LEVEL(x) ((x) << 3)
> -#define DP_LANE_POST_CURSOR(i, x) (((x) & 0x3) << (((i) & 1) << 2))
> -
> -/**
> - * struct drm_dp_link_train_set - link training settings
> - * @voltage_swing: per-lane voltage swing
> - * @pre_emphasis: per-lane pre-emphasis
> - * @post_cursor: per-lane post-cursor
> - */
> -struct drm_dp_link_train_set {
> - unsigned int voltage_swing[4];
> - unsigned int pre_emphasis[4];
> - unsigned int post_cursor[4];
> -};
> -
> -/**
> - * struct drm_dp_link_train - link training state information
> - * @request: currently requested settings
> - * @adjust: adjustments requested by sink
> - * @pattern: currently requested training pattern
> - * @clock_recovered: flag to track if clock recovery has completed
> - * @channel_equalized: flag to track if channel equalization has completed
> - */
> -struct drm_dp_link_train {
> - struct drm_dp_link_train_set request;
> - struct drm_dp_link_train_set adjust;
> -
> - unsigned int pattern;
> -
> - bool clock_recovered;
> - bool channel_equalized;
> -};
> -
> -/**
> - * struct drm_dp_link - DP link capabilities and configuration
> - * @revision: DP specification revision supported on the link
> - * @max_rate: maximum clock rate supported on the link
> - * @max_lanes: maximum number of lanes supported on the link
> - * @caps: capabilities supported on the link (see &drm_dp_link_caps)
> - * @aux_rd_interval: AUX read interval to use for training (in microseconds)
> - * @edp: eDP revision (0x11: eDP 1.1, 0x12: eDP 1.2, ...)
> - * @rate: currently configured link rate
> - * @lanes: currently configured number of lanes
> - * @rates: additional supported link rates in kHz (eDP 1.4)
> - * @num_rates: number of additional supported link rates (eDP 1.4)
> - */
> -struct drm_dp_link {
> - unsigned char revision;
> - unsigned int max_rate;
> - unsigned int max_lanes;
> -
> - struct drm_dp_link_caps caps;
> -
> - /**
> - * @cr: clock recovery read interval
> - * @ce: channel equalization read interval
> - */
> - struct {
> - unsigned int cr;
> - unsigned int ce;
> - } aux_rd_interval;
> -
> - unsigned char edp;
> -
> - unsigned int rate;
> - unsigned int lanes;
> -
> - unsigned long rates[DP_MAX_SUPPORTED_RATES];
> - unsigned int num_rates;
> -
> - /**
> - * @ops: DP link operations
> - */
> - const struct drm_dp_link_ops *ops;
> -
> - /**
> - * @aux: DP AUX channel
> - */
> - struct drm_dp_aux *aux;
> -
> - /**
> - * @train: DP link training state
> - */
> - struct drm_dp_link_train train;
> -};
> -
> -int drm_dp_link_add_rate(struct drm_dp_link *link, unsigned long rate);
> -int drm_dp_link_remove_rate(struct drm_dp_link *link, unsigned long rate);
> -void drm_dp_link_update_rates(struct drm_dp_link *link);
> -
> -int drm_dp_link_probe(struct drm_dp_aux *aux, struct drm_dp_link *link);
> -int drm_dp_link_power_up(struct drm_dp_aux *aux, struct drm_dp_link *link);
> -int drm_dp_link_power_down(struct drm_dp_aux *aux, struct drm_dp_link *link);
> -int drm_dp_link_configure(struct drm_dp_aux *aux, struct drm_dp_link *link);
> -int drm_dp_link_choose(struct drm_dp_link *link,
> - const struct drm_display_mode *mode,
> - const struct drm_display_info *info);
> -
> -void drm_dp_link_train_init(struct drm_dp_link_train *train);
> -int drm_dp_link_train(struct drm_dp_link *link);
> -
> -#endif
> diff --git a/drivers/gpu/drm/tegra/dpaux.c b/drivers/gpu/drm/tegra/dpaux.c
> index 622cdf1..066177a 100644
> --- a/drivers/gpu/drm/tegra/dpaux.c
> +++ b/drivers/gpu/drm/tegra/dpaux.c
> @@ -23,7 +23,6 @@
> #include <drm/drm_dp_helper.h>
> #include <drm/drm_panel.h>
>
> -#include "dp.h"
> #include "dpaux.h"
> #include "drm.h"
> #include "trace.h"
> diff --git a/drivers/gpu/drm/tegra/sor.c b/drivers/gpu/drm/tegra/sor.c
> index 615cb31..29c3ae8 100644
> --- a/drivers/gpu/drm/tegra/sor.c
> +++ b/drivers/gpu/drm/tegra/sor.c
> @@ -25,7 +25,6 @@
> #include <drm/drm_scdc_helper.h>
>
> #include "dc.h"
> -#include "dp.h"
> #include "drm.h"
> #include "hda.h"
> #include "sor.h"
> diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h
> index 51ecb51..04f6c0b 100644
> --- a/include/drm/drm_dp_helper.h
> +++ b/include/drm/drm_dp_helper.h
> @@ -1455,6 +1455,22 @@ static inline ssize_t drm_dp_dpcd_writeb(struct drm_dp_aux *aux,
> int drm_dp_dpcd_read_link_status(struct drm_dp_aux *aux,
> u8 status[DP_LINK_STATUS_SIZE]);
>
> +/*
> + * DisplayPort link
> + */
> +#define DP_LINK_CAP_ENHANCED_FRAMING (1 << 0)
> +
> +struct drm_dp_link {
> + unsigned char revision;
> + unsigned int rate;
> + unsigned int num_lanes;
> + unsigned long capabilities;
> +};
> +
> +int drm_dp_link_probe(struct drm_dp_aux *aux, struct drm_dp_link *link);
> +int drm_dp_link_power_up(struct drm_dp_aux *aux, struct drm_dp_link *link);
> +int drm_dp_link_power_down(struct drm_dp_aux *aux, struct drm_dp_link *link);
> +int drm_dp_link_configure(struct drm_dp_aux *aux, struct drm_dp_link *link);
> int drm_dp_downstream_max_clock(const u8 dpcd[DP_RECEIVER_CAP_SIZE],
> const u8 port_cap[4]);
> int drm_dp_downstream_max_bpc(const u8 dpcd[DP_RECEIVER_CAP_SIZE],
>