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authorThomas Zimmermann <tzimmermann@suse.de>2020-04-17 08:52:37 +0200
committerThomas Zimmermann <tzimmermann@suse.de>2020-04-17 08:52:39 +0200
commit948565468cfbf7f80eef58aa7f2b7c22dd518bf8 (patch)
treedb7b44f59e01d9ffe8e2ee7b21479598a5abc7f6 /drivers/gpu
parent08d99b2c23dfa84ca5b5e5c194062a0550888b71 (diff)
parent8cdf727119289db3a98835662eb28e1c5ad835f1 (diff)
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Merge tag 'topic/phy-compliance-2020-04-08' of git://anongit.freedesktop.org/drm/drm-misc into drm-misc-next
Topic pull request for topic/phy-compliance: - Standardize DP_PHY_TEST_PATTERN name. - Add support for setting/getting test pattern from sink. - Implement DP PHY compliance to i915. Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> # gpg: Signatur vom Mi 08 Apr 2020 14:46:42 CEST # gpg: mittels RSA-Schlüssel B97BD6A80CAC4981091AE547FE558C72A67013C3 # gpg: Signatur kann nicht geprüft werden: Kein öffentlicher Schlüssel From: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/efb3d0d9-2cf7-046b-3a9b-2548d086258e@linux.intel.com
Diffstat (limited to 'drivers/gpu')
-rw-r--r--drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c2
-rw-r--r--drivers/gpu/drm/drm_dp_helper.c94
-rw-r--r--drivers/gpu/drm/i915/display/intel_display_debugfs.c12
-rw-r--r--drivers/gpu/drm/i915/display/intel_display_types.h1
-rw-r--r--drivers/gpu/drm/i915/display/intel_dp.c171
-rw-r--r--drivers/gpu/drm/i915/display/intel_dp.h1
-rw-r--r--drivers/gpu/drm/i915/display/intel_dp_link_training.c9
-rw-r--r--drivers/gpu/drm/i915/display/intel_dp_link_training.h4
-rw-r--r--drivers/gpu/drm/i915/i915_reg.h18
9 files changed, 305 insertions, 7 deletions
diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c b/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c
index 7cbb1efb4f68..aa3c45a69b5e 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c
@@ -2530,7 +2530,7 @@ static void dp_test_send_phy_test_pattern(struct dc_link *link)
/* get phy test pattern and pattern parameters from DP receiver */
core_link_read_dpcd(
link,
- DP_TEST_PHY_PATTERN,
+ DP_PHY_TEST_PATTERN,
&dpcd_test_pattern.raw,
sizeof(dpcd_test_pattern));
core_link_read_dpcd(
diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c
index c6fbe6e6bc9d..28e59d1ffa93 100644
--- a/drivers/gpu/drm/drm_dp_helper.c
+++ b/drivers/gpu/drm/drm_dp_helper.c
@@ -1533,3 +1533,97 @@ int drm_dp_dsc_sink_supported_input_bpcs(const u8 dsc_dpcd[DP_DSC_RECEIVER_CAP_S
return num_bpc;
}
EXPORT_SYMBOL(drm_dp_dsc_sink_supported_input_bpcs);
+
+/**
+ * drm_dp_get_phy_test_pattern() - get the requested pattern from the sink.
+ * @aux: DisplayPort AUX channel
+ * @data: DP phy compliance test parameters.
+ *
+ * Returns 0 on success or a negative error code on failure.
+ */
+int drm_dp_get_phy_test_pattern(struct drm_dp_aux *aux,
+ struct drm_dp_phy_test_params *data)
+{
+ int err;
+ u8 rate, lanes;
+
+ err = drm_dp_dpcd_readb(aux, DP_TEST_LINK_RATE, &rate);
+ if (err < 0)
+ return err;
+ data->link_rate = drm_dp_bw_code_to_link_rate(rate);
+
+ err = drm_dp_dpcd_readb(aux, DP_TEST_LANE_COUNT, &lanes);
+ if (err < 0)
+ return err;
+ data->num_lanes = lanes & DP_MAX_LANE_COUNT_MASK;
+
+ if (lanes & DP_ENHANCED_FRAME_CAP)
+ data->enhanced_frame_cap = true;
+
+ err = drm_dp_dpcd_readb(aux, DP_PHY_TEST_PATTERN, &data->phy_pattern);
+ if (err < 0)
+ return err;
+
+ switch (data->phy_pattern) {
+ case DP_PHY_TEST_PATTERN_80BIT_CUSTOM:
+ err = drm_dp_dpcd_read(aux, DP_TEST_80BIT_CUSTOM_PATTERN_7_0,
+ &data->custom80, sizeof(data->custom80));
+ if (err < 0)
+ return err;
+
+ break;
+ case DP_PHY_TEST_PATTERN_CP2520:
+ err = drm_dp_dpcd_read(aux, DP_TEST_HBR2_SCRAMBLER_RESET,
+ &data->hbr2_reset,
+ sizeof(data->hbr2_reset));
+ if (err < 0)
+ return err;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL(drm_dp_get_phy_test_pattern);
+
+/**
+ * drm_dp_set_phy_test_pattern() - set the pattern to the sink.
+ * @aux: DisplayPort AUX channel
+ * @data: DP phy compliance test parameters.
+ *
+ * Returns 0 on success or a negative error code on failure.
+ */
+int drm_dp_set_phy_test_pattern(struct drm_dp_aux *aux,
+ struct drm_dp_phy_test_params *data, u8 dp_rev)
+{
+ int err, i;
+ u8 link_config[2];
+ u8 test_pattern;
+
+ link_config[0] = drm_dp_link_rate_to_bw_code(data->link_rate);
+ link_config[1] = data->num_lanes;
+ if (data->enhanced_frame_cap)
+ link_config[1] |= DP_LANE_COUNT_ENHANCED_FRAME_EN;
+ err = drm_dp_dpcd_write(aux, DP_LINK_BW_SET, link_config, 2);
+ if (err < 0)
+ return err;
+
+ test_pattern = data->phy_pattern;
+ if (dp_rev < 0x12) {
+ test_pattern = (test_pattern << 2) &
+ DP_LINK_QUAL_PATTERN_11_MASK;
+ err = drm_dp_dpcd_writeb(aux, DP_TRAINING_PATTERN_SET,
+ test_pattern);
+ if (err < 0)
+ return err;
+ } else {
+ for (i = 0; i < data->num_lanes; i++) {
+ err = drm_dp_dpcd_writeb(aux,
+ DP_LINK_QUAL_LANE0_SET + i,
+ test_pattern);
+ if (err < 0)
+ return err;
+ }
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL(drm_dp_set_phy_test_pattern);
diff --git a/drivers/gpu/drm/i915/display/intel_display_debugfs.c b/drivers/gpu/drm/i915/display/intel_display_debugfs.c
index 9f736420d83f..bdeea2e02642 100644
--- a/drivers/gpu/drm/i915/display/intel_display_debugfs.c
+++ b/drivers/gpu/drm/i915/display/intel_display_debugfs.c
@@ -1320,6 +1320,16 @@ static int i915_displayport_test_data_show(struct seq_file *m, void *data)
intel_dp->compliance.test_data.vdisplay);
seq_printf(m, "bpc: %u\n",
intel_dp->compliance.test_data.bpc);
+ } else if (intel_dp->compliance.test_type ==
+ DP_TEST_LINK_PHY_TEST_PATTERN) {
+ seq_printf(m, "pattern: %d\n",
+ intel_dp->compliance.test_data.phytest.phy_pattern);
+ seq_printf(m, "Number of lanes: %d\n",
+ intel_dp->compliance.test_data.phytest.num_lanes);
+ seq_printf(m, "Link Rate: %d\n",
+ intel_dp->compliance.test_data.phytest.link_rate);
+ seq_printf(m, "level: %02x\n",
+ intel_dp->train_set[0]);
}
} else
seq_puts(m, "0");
@@ -1352,7 +1362,7 @@ static int i915_displayport_test_type_show(struct seq_file *m, void *data)
if (encoder && connector->status == connector_status_connected) {
intel_dp = enc_to_intel_dp(encoder);
- seq_printf(m, "%02lx", intel_dp->compliance.test_type);
+ seq_printf(m, "%02lx\n", intel_dp->compliance.test_type);
} else
seq_puts(m, "0");
}
diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h b/drivers/gpu/drm/i915/display/intel_display_types.h
index e67474a71761..1170a1ce4b56 100644
--- a/drivers/gpu/drm/i915/display/intel_display_types.h
+++ b/drivers/gpu/drm/i915/display/intel_display_types.h
@@ -1238,6 +1238,7 @@ struct intel_dp_compliance_data {
u8 video_pattern;
u16 hdisplay, vdisplay;
u8 bpc;
+ struct drm_dp_phy_test_params phytest;
};
struct intel_dp_compliance {
diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
index 804b1d966f66..f2ee2a0f286a 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -5001,9 +5001,180 @@ static u8 intel_dp_autotest_edid(struct intel_dp *intel_dp)
return test_result;
}
+static u8 intel_dp_prepare_phytest(struct intel_dp *intel_dp)
+{
+ struct drm_dp_phy_test_params *data =
+ &intel_dp->compliance.test_data.phytest;
+
+ if (drm_dp_get_phy_test_pattern(&intel_dp->aux, data)) {
+ DRM_DEBUG_KMS("DP Phy Test pattern AUX read failure\n");
+ return DP_TEST_NAK;
+ }
+
+ /*
+ * link_mst is set to false to avoid executing mst related code
+ * during compliance testing.
+ */
+ intel_dp->link_mst = false;
+
+ return DP_TEST_ACK;
+}
+
+static void intel_dp_phy_pattern_update(struct intel_dp *intel_dp)
+{
+ struct drm_i915_private *dev_priv =
+ to_i915(dp_to_dig_port(intel_dp)->base.base.dev);
+ struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
+ struct drm_dp_phy_test_params *data =
+ &intel_dp->compliance.test_data.phytest;
+ struct intel_crtc *crtc = to_intel_crtc(intel_dig_port->base.base.crtc);
+ enum pipe pipe = crtc->pipe;
+ u32 pattern_val;
+
+ switch (data->phy_pattern) {
+ case DP_PHY_TEST_PATTERN_NONE:
+ DRM_DEBUG_KMS("Disable Phy Test Pattern\n");
+ intel_de_write(dev_priv, DDI_DP_COMP_CTL(pipe), 0x0);
+ break;
+ case DP_PHY_TEST_PATTERN_D10_2:
+ DRM_DEBUG_KMS("Set D10.2 Phy Test Pattern\n");
+ intel_de_write(dev_priv, DDI_DP_COMP_CTL(pipe),
+ DDI_DP_COMP_CTL_ENABLE | DDI_DP_COMP_CTL_D10_2);
+ break;
+ case DP_PHY_TEST_PATTERN_ERROR_COUNT:
+ DRM_DEBUG_KMS("Set Error Count Phy Test Pattern\n");
+ intel_de_write(dev_priv, DDI_DP_COMP_CTL(pipe),
+ DDI_DP_COMP_CTL_ENABLE |
+ DDI_DP_COMP_CTL_SCRAMBLED_0);
+ break;
+ case DP_PHY_TEST_PATTERN_PRBS7:
+ DRM_DEBUG_KMS("Set PRBS7 Phy Test Pattern\n");
+ intel_de_write(dev_priv, DDI_DP_COMP_CTL(pipe),
+ DDI_DP_COMP_CTL_ENABLE | DDI_DP_COMP_CTL_PRBS7);
+ break;
+ case DP_PHY_TEST_PATTERN_80BIT_CUSTOM:
+ /*
+ * FIXME: Ideally pattern should come from DPCD 0x250. As
+ * current firmware of DPR-100 could not set it, so hardcoding
+ * now for complaince test.
+ */
+ DRM_DEBUG_KMS("Set 80Bit Custom Phy Test Pattern 0x3e0f83e0 0x0f83e0f8 0x0000f83e\n");
+ pattern_val = 0x3e0f83e0;
+ intel_de_write(dev_priv, DDI_DP_COMP_PAT(pipe, 0), pattern_val);
+ pattern_val = 0x0f83e0f8;
+ intel_de_write(dev_priv, DDI_DP_COMP_PAT(pipe, 1), pattern_val);
+ pattern_val = 0x0000f83e;
+ intel_de_write(dev_priv, DDI_DP_COMP_PAT(pipe, 2), pattern_val);
+ intel_de_write(dev_priv, DDI_DP_COMP_CTL(pipe),
+ DDI_DP_COMP_CTL_ENABLE |
+ DDI_DP_COMP_CTL_CUSTOM80);
+ break;
+ case DP_PHY_TEST_PATTERN_CP2520:
+ /*
+ * FIXME: Ideally pattern should come from DPCD 0x24A. As
+ * current firmware of DPR-100 could not set it, so hardcoding
+ * now for complaince test.
+ */
+ DRM_DEBUG_KMS("Set HBR2 compliance Phy Test Pattern\n");
+ pattern_val = 0xFB;
+ intel_de_write(dev_priv, DDI_DP_COMP_CTL(pipe),
+ DDI_DP_COMP_CTL_ENABLE | DDI_DP_COMP_CTL_HBR2 |
+ pattern_val);
+ break;
+ default:
+ WARN(1, "Invalid Phy Test Pattern\n");
+ }
+}
+
+static void
+intel_dp_autotest_phy_ddi_disable(struct intel_dp *intel_dp)
+{
+ struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
+ struct drm_device *dev = intel_dig_port->base.base.dev;
+ struct drm_i915_private *dev_priv = to_i915(dev);
+ struct intel_crtc *crtc = to_intel_crtc(intel_dig_port->base.base.crtc);
+ enum pipe pipe = crtc->pipe;
+ u32 trans_ddi_func_ctl_value, trans_conf_value, dp_tp_ctl_value;
+
+ trans_ddi_func_ctl_value = intel_de_read(dev_priv,
+ TRANS_DDI_FUNC_CTL(pipe));
+ trans_conf_value = intel_de_read(dev_priv, PIPECONF(pipe));
+ dp_tp_ctl_value = intel_de_read(dev_priv, TGL_DP_TP_CTL(pipe));
+
+ trans_ddi_func_ctl_value &= ~(TRANS_DDI_FUNC_ENABLE |
+ TGL_TRANS_DDI_PORT_MASK);
+ trans_conf_value &= ~PIPECONF_ENABLE;
+ dp_tp_ctl_value &= ~DP_TP_CTL_ENABLE;
+
+ intel_de_write(dev_priv, PIPECONF(pipe), trans_conf_value);
+ intel_de_write(dev_priv, TRANS_DDI_FUNC_CTL(pipe),
+ trans_ddi_func_ctl_value);
+ intel_de_write(dev_priv, TGL_DP_TP_CTL(pipe), dp_tp_ctl_value);
+}
+
+static void
+intel_dp_autotest_phy_ddi_enable(struct intel_dp *intel_dp, uint8_t lane_cnt)
+{
+ struct intel_digital_port *intel_dig_port = dp_to_dig_port(intel_dp);
+ struct drm_device *dev = intel_dig_port->base.base.dev;
+ struct drm_i915_private *dev_priv = to_i915(dev);
+ enum port port = intel_dig_port->base.port;
+ struct intel_crtc *crtc = to_intel_crtc(intel_dig_port->base.base.crtc);
+ enum pipe pipe = crtc->pipe;
+ u32 trans_ddi_func_ctl_value, trans_conf_value, dp_tp_ctl_value;
+
+ trans_ddi_func_ctl_value = intel_de_read(dev_priv,
+ TRANS_DDI_FUNC_CTL(pipe));
+ trans_conf_value = intel_de_read(dev_priv, PIPECONF(pipe));
+ dp_tp_ctl_value = intel_de_read(dev_priv, TGL_DP_TP_CTL(pipe));
+
+ trans_ddi_func_ctl_value |= TRANS_DDI_FUNC_ENABLE |
+ TGL_TRANS_DDI_SELECT_PORT(port);
+ trans_conf_value |= PIPECONF_ENABLE;
+ dp_tp_ctl_value |= DP_TP_CTL_ENABLE;
+
+ intel_de_write(dev_priv, PIPECONF(pipe), trans_conf_value);
+ intel_de_write(dev_priv, TGL_DP_TP_CTL(pipe), dp_tp_ctl_value);
+ intel_de_write(dev_priv, TRANS_DDI_FUNC_CTL(pipe),
+ trans_ddi_func_ctl_value);
+}
+
+void intel_dp_process_phy_request(struct intel_dp *intel_dp)
+{
+ struct drm_dp_phy_test_params *data =
+ &intel_dp->compliance.test_data.phytest;
+ u8 link_status[DP_LINK_STATUS_SIZE];
+
+ if (!intel_dp_get_link_status(intel_dp, link_status)) {
+ DRM_DEBUG_KMS("failed to get link status\n");
+ return;
+ }
+
+ /* retrieve vswing & pre-emphasis setting */
+ intel_dp_get_adjust_train(intel_dp, link_status);
+
+ intel_dp_autotest_phy_ddi_disable(intel_dp);
+
+ intel_dp_set_signal_levels(intel_dp);
+
+ intel_dp_phy_pattern_update(intel_dp);
+
+ intel_dp_autotest_phy_ddi_enable(intel_dp, data->num_lanes);
+
+ drm_dp_set_phy_test_pattern(&intel_dp->aux, data,
+ link_status[DP_DPCD_REV]);
+}
+
static u8 intel_dp_autotest_phy_pattern(struct intel_dp *intel_dp)
{
u8 test_result = DP_TEST_NAK;
+
+ test_result = intel_dp_prepare_phytest(intel_dp);
+ if (test_result != DP_TEST_ACK)
+ DRM_ERROR("Phy test preparation failed\n");
+
+ intel_dp_process_phy_request(intel_dp);
+
return test_result;
}
diff --git a/drivers/gpu/drm/i915/display/intel_dp.h b/drivers/gpu/drm/i915/display/intel_dp.h
index 0c7be8ed1423..0d22a230b32d 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.h
+++ b/drivers/gpu/drm/i915/display/intel_dp.h
@@ -115,6 +115,7 @@ void intel_dp_hdr_metadata_enable(struct intel_dp *intel_dp,
const struct intel_crtc_state *crtc_state,
const struct drm_connector_state *conn_state);
bool intel_digital_port_connected(struct intel_encoder *encoder);
+void intel_dp_process_phy_request(struct intel_dp *intel_dp);
static inline unsigned int intel_dp_unused_lane_mask(int lane_count)
{
diff --git a/drivers/gpu/drm/i915/display/intel_dp_link_training.c b/drivers/gpu/drm/i915/display/intel_dp_link_training.c
index a7defb37ab00..e4f1843170b7 100644
--- a/drivers/gpu/drm/i915/display/intel_dp_link_training.c
+++ b/drivers/gpu/drm/i915/display/intel_dp_link_training.c
@@ -34,9 +34,8 @@ intel_dp_dump_link_status(const u8 link_status[DP_LINK_STATUS_SIZE])
link_status[3], link_status[4], link_status[5]);
}
-static void
-intel_get_adjust_train(struct intel_dp *intel_dp,
- const u8 link_status[DP_LINK_STATUS_SIZE])
+void intel_dp_get_adjust_train(struct intel_dp *intel_dp,
+ const u8 link_status[DP_LINK_STATUS_SIZE])
{
u8 v = 0;
u8 p = 0;
@@ -219,7 +218,7 @@ intel_dp_link_training_clock_recovery(struct intel_dp *intel_dp)
voltage = intel_dp->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK;
/* Update training set as requested by target */
- intel_get_adjust_train(intel_dp, link_status);
+ intel_dp_get_adjust_train(intel_dp, link_status);
if (!intel_dp_update_link_train(intel_dp)) {
drm_err(&i915->drm,
"failed to update link training\n");
@@ -338,7 +337,7 @@ intel_dp_link_training_channel_equalization(struct intel_dp *intel_dp)
}
/* Update training set as requested by target */
- intel_get_adjust_train(intel_dp, link_status);
+ intel_dp_get_adjust_train(intel_dp, link_status);
if (!intel_dp_update_link_train(intel_dp)) {
drm_err(&i915->drm,
"failed to update link training\n");
diff --git a/drivers/gpu/drm/i915/display/intel_dp_link_training.h b/drivers/gpu/drm/i915/display/intel_dp_link_training.h
index 174566adcc92..01f1dabbb060 100644
--- a/drivers/gpu/drm/i915/display/intel_dp_link_training.h
+++ b/drivers/gpu/drm/i915/display/intel_dp_link_training.h
@@ -6,8 +6,12 @@
#ifndef __INTEL_DP_LINK_TRAINING_H__
#define __INTEL_DP_LINK_TRAINING_H__
+#include <drm/drm_dp_helper.h>
+
struct intel_dp;
+void intel_dp_get_adjust_train(struct intel_dp *intel_dp,
+ const u8 link_status[DP_LINK_STATUS_SIZE]);
void intel_dp_start_link_train(struct intel_dp *intel_dp);
void intel_dp_stop_link_train(struct intel_dp *intel_dp);
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 59e64acc2c56..490e9f4a287a 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -9794,6 +9794,24 @@ enum skl_power_gate {
#define DDI_BUF_BALANCE_LEG_ENABLE (1 << 31)
#define DDI_BUF_TRANS_HI(port, i) _MMIO(_PORT(port, _DDI_BUF_TRANS_A, _DDI_BUF_TRANS_B) + (i) * 8 + 4)
+/* DDI DP Compliance Control */
+#define _DDI_DP_COMP_CTL_A 0x605F0
+#define _DDI_DP_COMP_CTL_B 0x615F0
+#define DDI_DP_COMP_CTL(pipe) _MMIO_PIPE(pipe, _DDI_DP_COMP_CTL_A, _DDI_DP_COMP_CTL_B)
+#define DDI_DP_COMP_CTL_ENABLE (1 << 31)
+#define DDI_DP_COMP_CTL_D10_2 (0 << 28)
+#define DDI_DP_COMP_CTL_SCRAMBLED_0 (1 << 28)
+#define DDI_DP_COMP_CTL_PRBS7 (2 << 28)
+#define DDI_DP_COMP_CTL_CUSTOM80 (3 << 28)
+#define DDI_DP_COMP_CTL_HBR2 (4 << 28)
+#define DDI_DP_COMP_CTL_SCRAMBLED_1 (5 << 28)
+#define DDI_DP_COMP_CTL_HBR2_RESET (0xFC << 0)
+
+/* DDI DP Compliance Pattern */
+#define _DDI_DP_COMP_PAT_A 0x605F4
+#define _DDI_DP_COMP_PAT_B 0x615F4
+#define DDI_DP_COMP_PAT(pipe, i) _MMIO(_PIPE(pipe, _DDI_DP_COMP_PAT_A, _DDI_DP_COMP_PAT_B) + (i) * 4)
+
/* Sideband Interface (SBI) is programmed indirectly, via
* SBI_ADDR, which contains the register offset; and SBI_DATA,
* which contains the payload */