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-rw-r--r--drivers/gpu/drm/drm_dp_helper.c83
-rw-r--r--drivers/gpu/drm/i915/i915_drv.h3
-rw-r--r--drivers/gpu/drm/i915/intel_display.c22
-rw-r--r--drivers/gpu/drm/i915/intel_dp.c45
-rw-r--r--drivers/gpu/drm/i915/intel_dp_mst.c5
-rw-r--r--drivers/gpu/drm/i915/intel_drv.h13
-rw-r--r--drivers/gpu/drm/i915/intel_lspcon.c2
-rw-r--r--include/drm/drm_dp_helper.h51
8 files changed, 166 insertions, 58 deletions
diff --git a/drivers/gpu/drm/drm_dp_helper.c b/drivers/gpu/drm/drm_dp_helper.c
index 3e5f52110ea1..213fb837e1c4 100644
--- a/drivers/gpu/drm/drm_dp_helper.c
+++ b/drivers/gpu/drm/drm_dp_helper.c
@@ -1208,3 +1208,86 @@ int drm_dp_stop_crc(struct drm_dp_aux *aux)
return 0;
}
EXPORT_SYMBOL(drm_dp_stop_crc);
+
+struct dpcd_quirk {
+ u8 oui[3];
+ bool is_branch;
+ u32 quirks;
+};
+
+#define OUI(first, second, third) { (first), (second), (third) }
+
+static const struct dpcd_quirk dpcd_quirk_list[] = {
+ /* Analogix 7737 needs reduced M and N at HBR2 link rates */
+ { OUI(0x00, 0x22, 0xb9), true, BIT(DP_DPCD_QUIRK_LIMITED_M_N) },
+};
+
+#undef OUI
+
+/*
+ * Get a bit mask of DPCD quirks for the sink/branch device identified by
+ * ident. The quirk data is shared but it's up to the drivers to act on the
+ * data.
+ *
+ * For now, only the OUI (first three bytes) is used, but this may be extended
+ * to device identification string and hardware/firmware revisions later.
+ */
+static u32
+drm_dp_get_quirks(const struct drm_dp_dpcd_ident *ident, bool is_branch)
+{
+ const struct dpcd_quirk *quirk;
+ u32 quirks = 0;
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(dpcd_quirk_list); i++) {
+ quirk = &dpcd_quirk_list[i];
+
+ if (quirk->is_branch != is_branch)
+ continue;
+
+ if (memcmp(quirk->oui, ident->oui, sizeof(ident->oui)) != 0)
+ continue;
+
+ quirks |= quirk->quirks;
+ }
+
+ return quirks;
+}
+
+/**
+ * drm_dp_read_desc - read sink/branch descriptor from DPCD
+ * @aux: DisplayPort AUX channel
+ * @desc: Device decriptor to fill from DPCD
+ * @is_branch: true for branch devices, false for sink devices
+ *
+ * Read DPCD 0x400 (sink) or 0x500 (branch) into @desc. Also debug log the
+ * identification.
+ *
+ * Returns 0 on success or a negative error code on failure.
+ */
+int drm_dp_read_desc(struct drm_dp_aux *aux, struct drm_dp_desc *desc,
+ bool is_branch)
+{
+ struct drm_dp_dpcd_ident *ident = &desc->ident;
+ unsigned int offset = is_branch ? DP_BRANCH_OUI : DP_SINK_OUI;
+ int ret, dev_id_len;
+
+ ret = drm_dp_dpcd_read(aux, offset, ident, sizeof(*ident));
+ if (ret < 0)
+ return ret;
+
+ desc->quirks = drm_dp_get_quirks(ident, is_branch);
+
+ dev_id_len = strnlen(ident->device_id, sizeof(ident->device_id));
+
+ DRM_DEBUG_KMS("DP %s: OUI %*phD dev-ID %*pE HW-rev %d.%d SW-rev %d.%d quirks 0x%04x\n",
+ is_branch ? "branch" : "sink",
+ (int)sizeof(ident->oui), ident->oui,
+ dev_id_len, ident->device_id,
+ ident->hw_rev >> 4, ident->hw_rev & 0xf,
+ ident->sw_major_rev, ident->sw_minor_rev,
+ desc->quirks);
+
+ return 0;
+}
+EXPORT_SYMBOL(drm_dp_read_desc);
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index c9b0949f6c1a..963f6d4481f7 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -562,7 +562,8 @@ struct intel_link_m_n {
void intel_link_compute_m_n(int bpp, int nlanes,
int pixel_clock, int link_clock,
- struct intel_link_m_n *m_n);
+ struct intel_link_m_n *m_n,
+ bool reduce_m_n);
/* Interface history:
*
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 3617927af269..3cabe52a4e3b 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -6101,7 +6101,7 @@ retry:
pipe_config->fdi_lanes = lane;
intel_link_compute_m_n(pipe_config->pipe_bpp, lane, fdi_dotclock,
- link_bw, &pipe_config->fdi_m_n);
+ link_bw, &pipe_config->fdi_m_n, false);
ret = ironlake_check_fdi_lanes(dev, intel_crtc->pipe, pipe_config);
if (ret == -EINVAL && pipe_config->pipe_bpp > 6*3) {
@@ -6277,7 +6277,8 @@ intel_reduce_m_n_ratio(uint32_t *num, uint32_t *den)
}
static void compute_m_n(unsigned int m, unsigned int n,
- uint32_t *ret_m, uint32_t *ret_n)
+ uint32_t *ret_m, uint32_t *ret_n,
+ bool reduce_m_n)
{
/*
* Reduce M/N as much as possible without loss in precision. Several DP
@@ -6285,9 +6286,11 @@ static void compute_m_n(unsigned int m, unsigned int n,
* values. The passed in values are more likely to have the least
* significant bits zero than M after rounding below, so do this first.
*/
- while ((m & 1) == 0 && (n & 1) == 0) {
- m >>= 1;
- n >>= 1;
+ if (reduce_m_n) {
+ while ((m & 1) == 0 && (n & 1) == 0) {
+ m >>= 1;
+ n >>= 1;
+ }
}
*ret_n = min_t(unsigned int, roundup_pow_of_two(n), DATA_LINK_N_MAX);
@@ -6298,16 +6301,19 @@ static void compute_m_n(unsigned int m, unsigned int n,
void
intel_link_compute_m_n(int bits_per_pixel, int nlanes,
int pixel_clock, int link_clock,
- struct intel_link_m_n *m_n)
+ struct intel_link_m_n *m_n,
+ bool reduce_m_n)
{
m_n->tu = 64;
compute_m_n(bits_per_pixel * pixel_clock,
link_clock * nlanes * 8,
- &m_n->gmch_m, &m_n->gmch_n);
+ &m_n->gmch_m, &m_n->gmch_n,
+ reduce_m_n);
compute_m_n(pixel_clock, link_clock,
- &m_n->link_m, &m_n->link_n);
+ &m_n->link_m, &m_n->link_n,
+ reduce_m_n);
}
static inline bool intel_panel_use_ssc(struct drm_i915_private *dev_priv)
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index ee77b519835c..fc691b8b317c 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -1507,37 +1507,6 @@ static void intel_dp_print_rates(struct intel_dp *intel_dp)
DRM_DEBUG_KMS("common rates: %s\n", str);
}
-bool
-__intel_dp_read_desc(struct intel_dp *intel_dp, struct intel_dp_desc *desc)
-{
- u32 base = drm_dp_is_branch(intel_dp->dpcd) ? DP_BRANCH_OUI :
- DP_SINK_OUI;
-
- return drm_dp_dpcd_read(&intel_dp->aux, base, desc, sizeof(*desc)) ==
- sizeof(*desc);
-}
-
-bool intel_dp_read_desc(struct intel_dp *intel_dp)
-{
- struct intel_dp_desc *desc = &intel_dp->desc;
- bool oui_sup = intel_dp->dpcd[DP_DOWN_STREAM_PORT_COUNT] &
- DP_OUI_SUPPORT;
- int dev_id_len;
-
- if (!__intel_dp_read_desc(intel_dp, desc))
- return false;
-
- dev_id_len = strnlen(desc->device_id, sizeof(desc->device_id));
- DRM_DEBUG_KMS("DP %s: OUI %*phD%s dev-ID %*pE HW-rev %d.%d SW-rev %d.%d\n",
- drm_dp_is_branch(intel_dp->dpcd) ? "branch" : "sink",
- (int)sizeof(desc->oui), desc->oui, oui_sup ? "" : "(NS)",
- dev_id_len, desc->device_id,
- desc->hw_rev >> 4, desc->hw_rev & 0xf,
- desc->sw_major_rev, desc->sw_minor_rev);
-
- return true;
-}
-
static int rate_to_index(int find, const int *rates)
{
int i = 0;
@@ -1624,6 +1593,8 @@ intel_dp_compute_config(struct intel_encoder *encoder,
int common_rates[DP_MAX_SUPPORTED_RATES] = {};
int common_len;
uint8_t link_bw, rate_select;
+ bool reduce_m_n = drm_dp_has_quirk(&intel_dp->desc,
+ DP_DPCD_QUIRK_LIMITED_M_N);
common_len = intel_dp_common_rates(intel_dp, common_rates);
@@ -1753,7 +1724,8 @@ found:
intel_link_compute_m_n(bpp, lane_count,
adjusted_mode->crtc_clock,
pipe_config->port_clock,
- &pipe_config->dp_m_n);
+ &pipe_config->dp_m_n,
+ reduce_m_n);
if (intel_connector->panel.downclock_mode != NULL &&
dev_priv->drrs.type == SEAMLESS_DRRS_SUPPORT) {
@@ -1761,7 +1733,8 @@ found:
intel_link_compute_m_n(bpp, lane_count,
intel_connector->panel.downclock_mode->clock,
pipe_config->port_clock,
- &pipe_config->dp_m2_n2);
+ &pipe_config->dp_m2_n2,
+ reduce_m_n);
}
/*
@@ -3622,7 +3595,8 @@ intel_edp_init_dpcd(struct intel_dp *intel_dp)
if (!intel_dp_read_dpcd(intel_dp))
return false;
- intel_dp_read_desc(intel_dp);
+ drm_dp_read_desc(&intel_dp->aux, &intel_dp->desc,
+ drm_dp_is_branch(intel_dp->dpcd));
if (intel_dp->dpcd[DP_DPCD_REV] >= 0x11)
dev_priv->no_aux_handshake = intel_dp->dpcd[DP_MAX_DOWNSPREAD] &
@@ -4624,7 +4598,8 @@ intel_dp_long_pulse(struct intel_connector *intel_connector)
intel_dp_print_rates(intel_dp);
- intel_dp_read_desc(intel_dp);
+ drm_dp_read_desc(&intel_dp->aux, &intel_dp->desc,
+ drm_dp_is_branch(intel_dp->dpcd));
intel_dp_configure_mst(intel_dp);
diff --git a/drivers/gpu/drm/i915/intel_dp_mst.c b/drivers/gpu/drm/i915/intel_dp_mst.c
index c1f62eb07c07..989e25577ac0 100644
--- a/drivers/gpu/drm/i915/intel_dp_mst.c
+++ b/drivers/gpu/drm/i915/intel_dp_mst.c
@@ -44,6 +44,8 @@ static bool intel_dp_mst_compute_config(struct intel_encoder *encoder,
int lane_count, slots;
const struct drm_display_mode *adjusted_mode = &pipe_config->base.adjusted_mode;
int mst_pbn;
+ bool reduce_m_n = drm_dp_has_quirk(&intel_dp->desc,
+ DP_DPCD_QUIRK_LIMITED_M_N);
pipe_config->has_pch_encoder = false;
bpp = 24;
@@ -75,7 +77,8 @@ static bool intel_dp_mst_compute_config(struct intel_encoder *encoder,
intel_link_compute_m_n(bpp, lane_count,
adjusted_mode->crtc_clock,
pipe_config->port_clock,
- &pipe_config->dp_m_n);
+ &pipe_config->dp_m_n,
+ reduce_m_n);
pipe_config->dp_m_n.tu = slots;
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index aaee3949a422..f630c7af5020 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -906,14 +906,6 @@ enum link_m_n_set {
M2_N2
};
-struct intel_dp_desc {
- u8 oui[3];
- u8 device_id[6];
- u8 hw_rev;
- u8 sw_major_rev;
- u8 sw_minor_rev;
-} __packed;
-
struct intel_dp_compliance_data {
unsigned long edid;
uint8_t video_pattern;
@@ -957,7 +949,7 @@ struct intel_dp {
/* Max link BW for the sink as per DPCD registers */
int max_sink_link_bw;
/* sink or branch descriptor */
- struct intel_dp_desc desc;
+ struct drm_dp_desc desc;
struct drm_dp_aux aux;
enum intel_display_power_domain aux_power_domain;
uint8_t train_set[4];
@@ -1532,9 +1524,6 @@ static inline unsigned int intel_dp_unused_lane_mask(int lane_count)
}
bool intel_dp_read_dpcd(struct intel_dp *intel_dp);
-bool __intel_dp_read_desc(struct intel_dp *intel_dp,
- struct intel_dp_desc *desc);
-bool intel_dp_read_desc(struct intel_dp *intel_dp);
int intel_dp_link_required(int pixel_clock, int bpp);
int intel_dp_max_data_rate(int max_link_clock, int max_lanes);
bool intel_digital_port_connected(struct drm_i915_private *dev_priv,
diff --git a/drivers/gpu/drm/i915/intel_lspcon.c b/drivers/gpu/drm/i915/intel_lspcon.c
index 71cbe9c08932..5abef482eacf 100644
--- a/drivers/gpu/drm/i915/intel_lspcon.c
+++ b/drivers/gpu/drm/i915/intel_lspcon.c
@@ -240,7 +240,7 @@ bool lspcon_init(struct intel_digital_port *intel_dig_port)
return false;
}
- intel_dp_read_desc(dp);
+ drm_dp_read_desc(&dp->aux, &dp->desc, drm_dp_is_branch(dp->dpcd));
DRM_DEBUG_KMS("Success: LSPCON init\n");
return true;
diff --git a/include/drm/drm_dp_helper.h b/include/drm/drm_dp_helper.h
index c0bd0d7651a9..bb837310c07e 100644
--- a/include/drm/drm_dp_helper.h
+++ b/include/drm/drm_dp_helper.h
@@ -913,4 +913,55 @@ void drm_dp_aux_unregister(struct drm_dp_aux *aux);
int drm_dp_start_crc(struct drm_dp_aux *aux, struct drm_crtc *crtc);
int drm_dp_stop_crc(struct drm_dp_aux *aux);
+struct drm_dp_dpcd_ident {
+ u8 oui[3];
+ u8 device_id[6];
+ u8 hw_rev;
+ u8 sw_major_rev;
+ u8 sw_minor_rev;
+} __packed;
+
+/**
+ * struct drm_dp_desc - DP branch/sink device descriptor
+ * @ident: DP device identification from DPCD 0x400 (sink) or 0x500 (branch).
+ * @quirks: Quirks; use drm_dp_has_quirk() to query for the quirks.
+ */
+struct drm_dp_desc {
+ struct drm_dp_dpcd_ident ident;
+ u32 quirks;
+};
+
+int drm_dp_read_desc(struct drm_dp_aux *aux, struct drm_dp_desc *desc,
+ bool is_branch);
+
+/**
+ * enum drm_dp_quirk - Display Port sink/branch device specific quirks
+ *
+ * Display Port sink and branch devices in the wild have a variety of bugs, try
+ * to collect them here. The quirks are shared, but it's up to the drivers to
+ * implement workarounds for them.
+ */
+enum drm_dp_quirk {
+ /**
+ * @DP_DPCD_QUIRK_LIMITED_M_N:
+ *
+ * The device requires main link attributes Mvid and Nvid to be limited
+ * to 16 bits.
+ */
+ DP_DPCD_QUIRK_LIMITED_M_N,
+};
+
+/**
+ * drm_dp_has_quirk() - does the DP device have a specific quirk
+ * @desc: Device decriptor filled by drm_dp_read_desc()
+ * @quirk: Quirk to query for
+ *
+ * Return true if DP device identified by @desc has @quirk.
+ */
+static inline bool
+drm_dp_has_quirk(const struct drm_dp_desc *desc, enum drm_dp_quirk quirk)
+{
+ return desc->quirks & BIT(quirk);
+}
+
#endif /* _DRM_DP_HELPER_H_ */
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-18 22:32:58 +0000