// SPDX-License-Identifier: MIT
/*
* Copyright 2024, Intel Corporation.
*/
#include "intel_alpm.h"
#include "intel_crtc.h"
#include "intel_de.h"
#include "intel_display_types.h"
#include "intel_dp.h"
#include "intel_dp_aux.h"
#include "intel_psr_regs.h"
bool intel_alpm_aux_wake_supported(struct intel_dp *intel_dp)
{
return intel_dp->alpm_dpcd & DP_ALPM_CAP;
}
bool intel_alpm_aux_less_wake_supported(struct intel_dp *intel_dp)
{
return intel_dp->alpm_dpcd & DP_ALPM_AUX_LESS_CAP;
}
void intel_alpm_init_dpcd(struct intel_dp *intel_dp)
{
u8 dpcd;
if (drm_dp_dpcd_readb(&intel_dp->aux, DP_RECEIVER_ALPM_CAP, &dpcd) < 0)
return;
intel_dp->alpm_dpcd = dpcd;
}
/*
* See Bspec: 71632 for the table
*
* Silence_period = tSilence,Min + ((tSilence,Max - tSilence,Min) / 2)
*
* Half cycle duration:
*
* Link rates 1.62 - 4.32 and tLFPS_Cycle = 70 ns
* FLOOR( (Link Rate * tLFPS_Cycle) / (2 * 10) )
*
* Link rates 5.4 - 8.1
* PORT_ALPM_LFPS_CTL[ LFPS Cycle Count ] = 10
* LFPS Period chosen is the mid-point of the min:max values from the table
* FLOOR( LFPS Period in Symbol clocks /
* (2 * PORT_ALPM_LFPS_CTL[ LFPS Cycle Count ]) )
*/
static bool _lnl_get_silence_period_and_lfps_half_cycle(int link_rate,
int *silence_period,
int *lfps_half_cycle)
{
switch (link_rate) {
case 162000:
*silence_period = 20;
*lfps_half_cycle = 5;
break;
case 216000:
*silence_period = 27;
*lfps_half_cycle = 7;
break;
case 243000:
*silence_period = 31;
*lfps_half_cycle = 8;
break;
case 270000:
*silence_period = 34;
*lfps_half_cycle = 9;
break;
case 324000:
*silence_period = 41;
*lfps_half_cycle = 11;
break;
case 432000:
*silence_period = 56;
*lfps_half_cycle = 15;
break;
case 540000:
*silence_period = 69;
*lfps_half_cycle = 12;
break;
case 648000:
*silence_period = 84;
*lfps_half_cycle = 15;
break;
case 675000:
*silence_period = 87;
*lfps_half_cycle = 15;
break;
case 810000:
*silence_period = 104;
*lfps_half_cycle = 19;
break;
default:
*silence_period = *lfps_half_cycle = -1;
return false;
}
return true;
}
/*
* AUX-Less Wake Time = CEILING( ((PHY P2 to P0) + tLFPS_Period, Max+
* tSilence, Max+ tPHY Establishment + tCDS) / tline)
* For the "PHY P2 to P0" latency see the PHY Power Control page
* (PHY P2 to P0) : https://gfxspecs.intel.com/Predator/Home/Index/68965
* : 12 us
* The tLFPS_Period, Max term is 800ns
* The tSilence, Max term is 180ns
* The tPHY Establishment (a.k.a. t1) term is 50us
* The tCDS term is 1 or 2 times t2
* t2 = Number ML_PHY_LOCK * tML_PHY_LOCK
* Number ML_PHY_LOCK = ( 7 + CEILING( 6.5us / tML_PHY_LOCK ) + 1)
* Rounding up the 6.5us padding to the next ML_PHY_LOCK boundary and
* adding the "+ 1" term ensures all ML_PHY_LOCK sequences that start
* within the CDS period complete within the CDS period regardless of
* entry into the period
* tML_PHY_LOCK = TPS4 Length * ( 10 / (Link Rate in MHz) )
* TPS4 Length = 252 Symbols
*/
static int _lnl_compute_aux_less_wake_time(int port_clock)
{
int tphy2_p2_to_p0 = 12 * 1000;
int tlfps_period_max = 800;
int tsilence_max = 180;
int t1 = 50 * 1000;
int tps4 = 252;
/* port_clock is link rate in 10kbit/s units */
int tml_phy_lock = 1000 * 1000 * tps4 / port_clock;
int num_ml_phy_lock = 7 + DIV_ROUND_UP(6500, tml_phy_lock) + 1;
int t2 = num_ml_phy_lock * tml_phy_lock;
int tcds = 1 * t2;
return DIV_ROUND_UP(tphy2_p2_to_p0 + tlfps_period_max + tsilence_max +
t1 + tcds, 1000);
}
static int
_lnl_compute_aux_less_alpm_params(struct intel_dp *intel_dp,
const struct intel_crtc_state *crtc_state)
{
struct intel_display *display = to_intel_display(intel_dp);
int aux_less_wake_time, aux_less_wake_lines, silence_period,
lfps_half_cycle;
aux_less_wake_time =
_lnl_compute_aux_less_wake_time(crtc_state->port_clock);
aux_less_wake_lines = intel_usecs_to_scanlines(&crtc_state->hw.adjusted_mode,
aux_less_wake_time);
if (!_lnl_get_silence_period_and_lfps_half_cycle(crtc_state->port_clock,
&silence_period,
&lfps_half_cycle))
return false;
if (aux_less_wake_lines > ALPM_CTL_AUX_LESS_WAKE_TIME_MASK ||
silence_period > PORT_ALPM_CTL_SILENCE_PERIOD_MASK ||
lfps_half_cycle > PORT_ALPM_LFPS_CTL_LAST_LFPS_HALF_CYCLE_DURATION_MASK)
return false;
if (display->params.psr_safest_params)
aux_less_wake_lines = ALPM_CTL_AUX_LESS_WAKE_TIME_MASK;
intel_dp->alpm_parameters.aux_less_wake_lines = aux_less_wake_lines;
intel_dp->alpm_parameters.silence_period_sym_clocks = silence_period;
intel_dp->alpm_parameters.lfps_half_cycle_num_of_syms = lfps_half_cycle;
return true;
}
static bool _lnl_compute_alpm_params(struct intel_dp *intel_dp,
const struct intel_crtc_state *crtc_state)
{
struct intel_display *display = to_intel_display(intel_dp);
int check_entry_lines;
if (DISPLAY_VER(display) < 20)
return true;
/* ALPM Entry Check = 2 + CEILING( 5us /tline ) */
check_entry_lines = 2 +
intel_usecs_to_scanlines(&crtc_state->hw.adjusted_mode, 5);
if (check_entry_lines > 15)
return false;
if (!_lnl_compute_aux_less_alpm_params(intel_dp, crtc_state))
return false;
if (display->params.psr_safest_params)
check_entry_lines = 15;
intel_dp->alpm_parameters.check_entry_lines = check_entry_lines;
return true;
}
/*
* IO wake time for DISPLAY_VER < 12 is not directly mentioned in Bspec. There
* are 50 us io wake time and 32 us fast wake time. Clearly preharge pulses are
* not (improperly) included in 32 us fast wake time. 50 us - 32 us = 18 us.
*/
static int skl_io_buffer_wake_time(void)
{
return 18;
}
static int tgl_io_buffer_wake_time(void)
{
return 10;
}
static int io_buffer_wake_time(const struct intel_crtc_state *crtc_state)
{
struct intel_display *display = to_intel_display(crtc_state);
if (DISPLAY_VER(display) >= 12)
return tgl_io_buffer_wake_time();
else
return skl_io_buffer_wake_time();
}
bool intel_alpm_compute_params(struct intel_dp *intel_dp,
const struct intel_crtc_state *crtc_state)
{
struct intel_display *display = to_intel_display(intel_dp);
int io_wake_lines, io_wake_time, fast_wake_lines, fast_wake_time;
int tfw_exit_latency = 20; /* eDP spec */
int phy_wake = 4; /* eDP spec */
int preamble = 8; /* eDP spec */
int precharge = intel_dp_aux_fw_sync_len(intel_dp) - preamble;
u8 max_wake_lines;
io_wake_time = max(precharge, io_buffer_wake_time(crtc_state)) +
preamble + phy_wake + tfw_exit_latency;
fast_wake_time = precharge + preamble + phy_wake +
tfw_exit_latency;
if (DISPLAY_VER(display) >= 20)
max_wake_lines = 68;
else if (DISPLAY_VER(display) >= 12)
max_wake_lines = 12;
else
max_wake_lines = 8;
io_wake_lines = intel_usecs_to_scanlines(
&crtc_state->hw.adjusted_mode, io_wake_time);
fast_wake_lines = intel_usecs_to_scanlines(
&crtc_state->hw.adjusted_mode, fast_wake_time);
if (io_wake_lines > max_wake_lines ||
fast_wake_lines > max_wake_lines)
return false;
if (!_lnl_compute_alpm_params(intel_dp, crtc_state))
return false;
if (display->params.psr_safest_params)
io_wake_lines = fast_wake_lines = max_wake_lines;
/* According to Bspec lower limit should be set as 7 lines. */
intel_dp->alpm_parameters.io_wake_lines = max(io_wake_lines, 7);
intel_dp->alpm_parameters.fast_wake_lines = max(fast_wake_lines, 7);
return true;
}
void intel_alpm_lobf_compute_config(struct intel_dp *intel_dp,
struct intel_crtc_state *crtc_state,
struct drm_connector_state *conn_state)
{
struct intel_display *display = to_intel_display(intel_dp);
struct drm_display_mode *adjusted_mode = &crtc_state->hw.adjusted_mode;
int waketime_in_lines, first_sdp_position;
int context_latency, guardband;
if (!intel_dp_is_edp(intel_dp))
return;
if (DISPLAY_VER(display) < 20)
return;
if (!intel_dp->as_sdp_supported)
return;
if (crtc_state->has_psr)
return;
if (!(intel_alpm_aux_wake_supported(intel_dp) ||
intel_alpm_aux_less_wake_supported(intel_dp)))
return;
if (!intel_alpm_compute_params(intel_dp, crtc_state))
return;
context_latency = adjusted_mode->crtc_vblank_start - adjusted_mode->crtc_vdisplay;
guardband = adjusted_mode->crtc_vtotal -
adjusted_mode->crtc_vdisplay - context_latency;
first_sdp_position = adjusted_mode->crtc_vtotal - adjusted_mode->crtc_vsync_start;
if (intel_alpm_aux_less_wake_supported(intel_dp))
waketime_in_lines = intel_dp->alpm_parameters.io_wake_lines;
else
waketime_in_lines = intel_dp->alpm_parameters.aux_less_wake_lines;
crtc_state->has_lobf = (context_latency + guardband) >
(first_sdp_position + waketime_in_lines);
}
static void lnl_alpm_configure(struct intel_dp *intel_dp,
const struct intel_crtc_state *crtc_state)
{
struct intel_display *display = to_intel_display(intel_dp);
enum transcoder cpu_transcoder = crtc_state->cpu_transcoder;
enum port port = dp_to_dig_port(intel_dp)->base.port;
u32 alpm_ctl;
if (DISPLAY_VER(display) < 20 ||
(!intel_dp->psr.sel_update_enabled && !intel_dp_is_edp(intel_dp)))
return;
/*
* Panel Replay on eDP is always using ALPM aux less. I.e. no need to
* check panel support at this point.
*/
if ((intel_dp->psr.panel_replay_enabled && intel_dp_is_edp(intel_dp)) ||
(crtc_state->has_lobf && intel_alpm_aux_less_wake_supported(intel_dp))) {
alpm_ctl = ALPM_CTL_ALPM_ENABLE |
ALPM_CTL_ALPM_AUX_LESS_ENABLE |
ALPM_CTL_AUX_LESS_SLEEP_HOLD_TIME_50_SYMBOLS |
ALPM_CTL_AUX_LESS_WAKE_TIME(intel_dp->alpm_parameters.aux_less_wake_lines);
intel_de_write(display,
PORT_ALPM_CTL(display, port),
PORT_ALPM_CTL_ALPM_AUX_LESS_ENABLE |
PORT_ALPM_CTL_MAX_PHY_SWING_SETUP(15) |
PORT_ALPM_CTL_MAX_PHY_SWING_HOLD(0) |
PORT_ALPM_CTL_SILENCE_PERIOD(
intel_dp->alpm_parameters.silence_period_sym_clocks));
intel_de_write(display,
PORT_ALPM_LFPS_CTL(display, port),
PORT_ALPM_LFPS_CTL_LFPS_CYCLE_COUNT(10) |
PORT_ALPM_LFPS_CTL_LFPS_HALF_CYCLE_DURATION(
intel_dp->alpm_parameters.lfps_half_cycle_num_of_syms) |
PORT_ALPM_LFPS_CTL_FIRST_LFPS_HALF_CYCLE_DURATION(
intel_dp->alpm_parameters.lfps_half_cycle_num_of_syms) |
PORT_ALPM_LFPS_CTL_LAST_LFPS_HALF_CYCLE_DURATION(
intel_dp->alpm_parameters.lfps_half_cycle_num_of_syms));
} else {
alpm_ctl = ALPM_CTL_EXTENDED_FAST_WAKE_ENABLE |
ALPM_CTL_EXTENDED_FAST_WAKE_TIME(intel_dp->alpm_parameters.fast_wake_lines);
}
if (crtc_state->has_lobf)
alpm_ctl |= ALPM_CTL_LOBF_ENABLE;
alpm_ctl |= ALPM_CTL_ALPM_ENTRY_CHECK(intel_dp->alpm_parameters.check_entry_lines);
intel_de_write(display, ALPM_CTL(display, cpu_transcoder), alpm_ctl);
}
void intel_alpm_configure(struct intel_dp *intel_dp,
const struct intel_crtc_state *crtc_state)
{
lnl_alpm_configure(intel_dp, crtc_state);
}
static int i915_edp_lobf_info_show(struct seq_file *m, void *data)
{
struct intel_connector *connector = m->private;
struct intel_display *display = to_intel_display(connector);
struct drm_crtc *crtc;
struct intel_crtc_state *crtc_state;
enum transcoder cpu_transcoder;
u32 alpm_ctl;
int ret;
ret = drm_modeset_lock_single_interruptible(&display->drm->mode_config.connection_mutex);
if (ret)
return ret;
crtc = connector->base.state->crtc;
if (connector->base.status != connector_status_connected || !crtc) {
ret = -ENODEV;
goto out;
}
crtc_state = to_intel_crtc_state(crtc->state);
cpu_transcoder = crtc_state->cpu_transcoder;
alpm_ctl = intel_de_read(display, ALPM_CTL(display, cpu_transcoder));
seq_printf(m, "LOBF status: %s\n", str_enabled_disabled(alpm_ctl & ALPM_CTL_LOBF_ENABLE));
seq_printf(m, "Aux-wake alpm status: %s\n",
str_enabled_disabled(!(alpm_ctl & ALPM_CTL_ALPM_AUX_LESS_ENABLE)));
seq_printf(m, "Aux-less alpm status: %s\n",
str_enabled_disabled(alpm_ctl & ALPM_CTL_ALPM_AUX_LESS_ENABLE));
out:
drm_modeset_unlock(&display->drm->mode_config.connection_mutex);
return ret;
}
DEFINE_SHOW_ATTRIBUTE(i915_edp_lobf_info);
void intel_alpm_lobf_debugfs_add(struct intel_connector *connector)
{
struct intel_display *display = to_intel_display(connector);
struct dentry *root = connector->base.debugfs_entry;
if (DISPLAY_VER(display) < 20 ||
connector->base.connector_type != DRM_MODE_CONNECTOR_eDP)
return;
debugfs_create_file("i915_edp_lobf_info", 0444, root,
connector, &i915_edp_lobf_info_fops);
}
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