[PATCH 2/7] drm/i915: Remove link_status field from intel_dp structure

Keith Packard
2011-11-02T06:21:08Z

No persistent data was ever stored here, so link_status is instead
allocated on the stack as needed.

Signed-off-by: Keith Packard <keithp@keithp.com>
---
drivers/gpu/drm/i915/intel_dp.c | 65 +++++++++++++++++++++-----------------
1 files changed, 36 insertions(+), 29 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index efe5f9e..2c0c482 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -58,7 +58,6 @@ struct intel_dp {
struct i2c_algo_dp_aux_data algo;
bool is_pch_edp;
uint8_t train_set[4];
- uint8_t link_status[DP_LINK_STATUS_SIZE];
int panel_power_up_delay;
int panel_power_down_delay;
int panel_power_cycle_delay;
@@ -1285,11 +1284,11 @@ intel_dp_aux_native_read_retry(struct intel_dp *intel_dp, uint16_t address,
* link status information
*/
static bool
-intel_dp_get_link_status(struct intel_dp *intel_dp)
+intel_dp_get_link_status(struct intel_dp *intel_dp, uint8_t link_status[DP_LINK_STATUS_SIZE])
{
return intel_dp_aux_native_read_retry(intel_dp,
DP_LANE0_1_STATUS,
- intel_dp->link_status,
+ link_status,
DP_LINK_STATUS_SIZE);
}

@@ -1301,27 +1300,25 @@ intel_dp_link_status(uint8_t link_status[DP_LINK_STATUS_SIZE],
}

static uint8_t
-intel_get_adjust_request_voltage(uint8_t link_status[DP_LINK_STATUS_SIZE],
+intel_get_adjust_request_voltage(uint8_t adjust_request[2],
int lane)
{
- int i = DP_ADJUST_REQUEST_LANE0_1 + (lane >> 1);
int s = ((lane & 1) ?
DP_ADJUST_VOLTAGE_SWING_LANE1_SHIFT :
DP_ADJUST_VOLTAGE_SWING_LANE0_SHIFT);
- uint8_t l = intel_dp_link_status(link_status, i);
+ uint8_t l = adjust_request[lane>>1];

return ((l >> s) & 3) << DP_TRAIN_VOLTAGE_SWING_SHIFT;
}

static uint8_t
-intel_get_adjust_request_pre_emphasis(uint8_t link_status[DP_LINK_STATUS_SIZE],
+intel_get_adjust_request_pre_emphasis(uint8_t adjust_request[2],
int lane)
{
- int i = DP_ADJUST_REQUEST_LANE0_1 + (lane >> 1);
int s = ((lane & 1) ?
DP_ADJUST_PRE_EMPHASIS_LANE1_SHIFT :
DP_ADJUST_PRE_EMPHASIS_LANE0_SHIFT);
- uint8_t l = intel_dp_link_status(link_status, i);
+ uint8_t l = adjust_request[lane>>1];

return ((l >> s) & 3) << DP_TRAIN_PRE_EMPHASIS_SHIFT;
}
@@ -1362,15 +1359,18 @@ intel_dp_pre_emphasis_max(uint8_t voltage_swing)
}

static void
-intel_get_adjust_train(struct intel_dp *intel_dp)
+intel_get_adjust_train(struct intel_dp *intel_dp, uint8_t link_status[DP_LINK_STATUS_SIZE])
{
+ struct drm_device *dev = intel_dp->base.base.dev;
uint8_t v = 0;
uint8_t p = 0;
int lane;
+ uint8_t *adjust_request = link_status + (DP_ADJUST_REQUEST_LANE0_1 - DP_LANE0_1_STATUS);
+ int voltage_max;

for (lane = 0; lane < intel_dp->lane_count; lane++) {
- uint8_t this_v = intel_get_adjust_request_voltage(intel_dp->link_status, lane);
- uint8_t this_p = intel_get_adjust_request_pre_emphasis(intel_dp->link_status, lane);
+ uint8_t this_v = intel_get_adjust_request_voltage(adjust_request, lane);
+ uint8_t this_p = intel_get_adjust_request_pre_emphasis(adjust_request, lane);

if (this_v > v)
v = this_v;
@@ -1389,7 +1389,7 @@ intel_get_adjust_train(struct intel_dp *intel_dp)
}

static uint32_t
-intel_dp_signal_levels(uint8_t train_set, int lane_count)
+intel_dp_signal_levels(uint8_t train_set)
{
uint32_t signal_levels = 0;

@@ -1458,9 +1458,8 @@ static uint8_t
intel_get_lane_status(uint8_t link_status[DP_LINK_STATUS_SIZE],
int lane)
{
- int i = DP_LANE0_1_STATUS + (lane >> 1);
int s = (lane & 1) * 4;
- uint8_t l = intel_dp_link_status(link_status, i);
+ uint8_t l = link_status[lane>>1];

return (l >> s) & 0xf;
}
@@ -1485,18 +1484,18 @@ intel_clock_recovery_ok(uint8_t link_status[DP_LINK_STATUS_SIZE], int lane_count
DP_LANE_CHANNEL_EQ_DONE|\
DP_LANE_SYMBOL_LOCKED)
static bool
-intel_channel_eq_ok(struct intel_dp *intel_dp)
+intel_channel_eq_ok(struct intel_dp *intel_dp, uint8_t link_status[DP_LINK_STATUS_SIZE])
{
uint8_t lane_align;
uint8_t lane_status;
int lane;

- lane_align = intel_dp_link_status(intel_dp->link_status,
+ lane_align = intel_dp_link_status(link_status,
DP_LANE_ALIGN_STATUS_UPDATED);
if ((lane_align & DP_INTERLANE_ALIGN_DONE) == 0)
return false;
for (lane = 0; lane < intel_dp->lane_count; lane++) {
- lane_status = intel_get_lane_status(intel_dp->link_status, lane);
+ lane_status = intel_get_lane_status(link_status, lane);
if ((lane_status & CHANNEL_EQ_BITS) != CHANNEL_EQ_BITS)
return false;
}
@@ -1569,12 +1568,14 @@ intel_dp_start_link_train(struct intel_dp *intel_dp)
clock_recovery = false;
for (;;) {
/* Use intel_dp->train_set[0] to set the voltage and pre emphasis values */
+ uint8_t link_status[DP_LINK_STATUS_SIZE];
uint32_t signal_levels;
if (IS_GEN6(dev) && is_edp(intel_dp)) {
signal_levels = intel_gen6_edp_signal_levels(intel_dp->train_set[0]);
DP = (DP & ~EDP_LINK_TRAIN_VOL_EMP_MASK_SNB) | signal_levels;
} else {
- signal_levels = intel_dp_signal_levels(intel_dp->train_set[0], intel_dp->lane_count);
+ signal_levels = intel_dp_signal_levels(intel_dp->train_set[0]);
+ DRM_DEBUG_KMS("training pattern 1 signal levels %08x\n", signal_levels);
DP = (DP & ~(DP_VOLTAGE_MASK|DP_PRE_EMPHASIS_MASK)) | signal_levels;
}

@@ -1590,10 +1591,13 @@ intel_dp_start_link_train(struct intel_dp *intel_dp)
/* Set training pattern 1 */

udelay(100);
- if (!intel_dp_get_link_status(intel_dp))
+ if (!intel_dp_get_link_status(intel_dp, link_status)) {
+ DRM_ERROR("failed to get link status\n");
break;
+ }

- if (intel_clock_recovery_ok(intel_dp->link_status, intel_dp->lane_count)) {
+ if (intel_clock_recovery_ok(link_status, intel_dp->lane_count)) {
+ DRM_DEBUG_KMS("clock recovery OK\n");
clock_recovery = true;
break;
}
@@ -1615,7 +1619,7 @@ intel_dp_start_link_train(struct intel_dp *intel_dp)
voltage = intel_dp->train_set[0] & DP_TRAIN_VOLTAGE_SWING_MASK;

/* Compute new intel_dp->train_set as requested by target */
- intel_get_adjust_train(intel_dp);
+ intel_get_adjust_train(intel_dp, link_status);
}

intel_dp->DP = DP;
@@ -1638,6 +1642,7 @@ intel_dp_complete_link_train(struct intel_dp *intel_dp)
for (;;) {
/* Use intel_dp->train_set[0] to set the voltage and pre emphasis values */
uint32_t signal_levels;
+ uint8_t link_status[DP_LINK_STATUS_SIZE];

if (cr_tries > 5) {
DRM_ERROR("failed to train DP, aborting\n");
@@ -1649,7 +1654,8 @@ intel_dp_complete_link_train(struct intel_dp *intel_dp)
signal_levels = intel_gen6_edp_signal_levels(intel_dp->train_set[0]);
DP = (DP & ~EDP_LINK_TRAIN_VOL_EMP_MASK_SNB) | signal_levels;
} else {
- signal_levels = intel_dp_signal_levels(intel_dp->train_set[0], intel_dp->lane_count);
+ signal_levels = intel_dp_signal_levels(intel_dp->train_set[0]);
+ DRM_DEBUG_KMS("training pattern 1 signal levels %08x\n", signal_levels);
DP = (DP & ~(DP_VOLTAGE_MASK|DP_PRE_EMPHASIS_MASK)) | signal_levels;
}

@@ -1665,17 +1671,17 @@ intel_dp_complete_link_train(struct intel_dp *intel_dp)
break;

udelay(400);
- if (!intel_dp_get_link_status(intel_dp))
+ if (!intel_dp_get_link_status(intel_dp, link_status))
break;

/* Make sure clock is still ok */
- if (!intel_clock_recovery_ok(intel_dp->link_status, intel_dp->lane_count)) {
+ if (!intel_clock_recovery_ok(link_status, intel_dp->lane_count)) {
intel_dp_start_link_train(intel_dp);
cr_tries++;
continue;
}

- if (intel_channel_eq_ok(intel_dp)) {
+ if (intel_channel_eq_ok(intel_dp, link_status)) {
channel_eq = true;
break;
}
@@ -1690,7 +1696,7 @@ intel_dp_complete_link_train(struct intel_dp *intel_dp)
}

/* Compute new intel_dp->train_set as requested by target */
- intel_get_adjust_train(intel_dp);
+ intel_get_adjust_train(intel_dp, link_status);
++tries;
}

@@ -1822,6 +1828,7 @@ static void
intel_dp_check_link_status(struct intel_dp *intel_dp)
{
u8 sink_irq_vector;
+ u8 link_status[DP_LINK_STATUS_SIZE];

if (intel_dp->dpms_mode != DRM_MODE_DPMS_ON)
return;
@@ -1830,7 +1837,7 @@ intel_dp_check_link_status(struct intel_dp *intel_dp)
return;

/* Try to read receiver status if the link appears to be up */
- if (!intel_dp_get_link_status(intel_dp)) {
+ if (!intel_dp_get_link_status(intel_dp, link_status)) {
intel_dp_link_down(intel_dp);
return;
}
@@ -1855,7 +1862,7 @@ intel_dp_check_link_status(struct intel_dp *intel_dp)
DRM_DEBUG_DRIVER("CP or sink specific irq unhandled\n");
}

- if (!intel_channel_eq_ok(intel_dp)) {
+ if (!intel_channel_eq_ok(intel_dp, link_status)) {
DRM_DEBUG_KMS("%s: channel EQ not ok, retraining\n",
drm_get_encoder_name(&intel_dp->base.base));
intel_dp_start_link_train(intel_dp);
--
1.7.7