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path: root/drivers/gpu/drm/i915/display/intel_alpm.c
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Diffstat (limited to 'drivers/gpu/drm/i915/display/intel_alpm.c')
-rw-r--r--drivers/gpu/drm/i915/display/intel_alpm.c415
1 files changed, 415 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/display/intel_alpm.c b/drivers/gpu/drm/i915/display/intel_alpm.c
new file mode 100644
index 000000000000..866b3b409c4d
--- /dev/null
+++ b/drivers/gpu/drm/i915/display/intel_alpm.c
@@ -0,0 +1,415 @@
+// 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 drm_i915_private *i915 = dp_to_i915(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 (i915->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 drm_i915_private *i915 = dp_to_i915(intel_dp);
+ int check_entry_lines;
+
+ if (DISPLAY_VER(i915) < 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 (i915->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 drm_i915_private *i915 = to_i915(crtc_state->uapi.crtc->dev);
+
+ if (DISPLAY_VER(i915) >= 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 drm_i915_private *i915 = dp_to_i915(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() - 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(i915) >= 20)
+ max_wake_lines = 68;
+ else if (DISPLAY_VER(i915) >= 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 (i915->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 drm_i915_private *i915 = dp_to_i915(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(i915) < 20)
+ return;
+
+ if (!intel_dp_as_sdp_supported(intel_dp))
+ 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 drm_i915_private *dev_priv = dp_to_i915(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(dev_priv) < 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(dev_priv,
+ PORT_ALPM_CTL(dev_priv, 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(dev_priv,
+ PORT_ALPM_LFPS_CTL(dev_priv, 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(dev_priv, ALPM_CTL(dev_priv, 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 drm_i915_private *dev_priv = to_i915(connector->base.dev);
+ 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(&dev_priv->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(dev_priv, ALPM_CTL(dev_priv, 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(&dev_priv->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 drm_i915_private *i915 = to_i915(connector->base.dev);
+ struct dentry *root = connector->base.debugfs_entry;
+
+ if (DISPLAY_VER(i915) < 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);
+}