[PATCH 3/6] drm/i915/lvds: Restore initial HW state during encoder enabling

Imre Deak
2016-08-09T11:34:16Z

Atm the LVDS encoder depends on the PPS HW context being saved/restored
from generic suspend/resume code. Since the PPS is specific to the LVDS
and eDP encoders a cleaner way is to reinitialize it during encoder
enabling, so do this here for LVDS. Follow-up patches will init the PPS
for the eDP encoder similarly and remove the suspend/resume time save /
restore.

Signed-off-by: Imre Deak <imre.deak@intel.com>
---
drivers/gpu/drm/i915/i915_reg.h | 1 +
drivers/gpu/drm/i915/intel_lvds.c | 103 +++++++++++++++++++++++++++++++++-----
2 files changed, 91 insertions(+), 13 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 889508f..da82744 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -3710,6 +3710,7 @@ enum {

#define _PP_ON_DELAYS 0x61208
#define PP_ON_DELAYS(pps_idx) _MMIO_PPS(pps_idx, _PP_ON_DELAYS)
+#define PANEL_PORT_SELECT_SHIFT 30
#define PANEL_PORT_SELECT_MASK (3 << 30)
#define PANEL_PORT_SELECT_LVDS (0 << 30)
#define PANEL_PORT_SELECT_DPA (1 << 30)
diff --git a/drivers/gpu/drm/i915/intel_lvds.c b/drivers/gpu/drm/i915/intel_lvds.c
index c5739fc..d5158e5 100644
--- a/drivers/gpu/drm/i915/intel_lvds.c
+++ b/drivers/gpu/drm/i915/intel_lvds.c
@@ -48,6 +48,20 @@ struct intel_lvds_connector {
struct notifier_block lid_notifier;
};

+struct intel_lvds_pps {
+ /* 100us units */
+ int t1_t2;
+ int t3;
+ int t4;
+ int t5;
+ int tx;
+
+ int divider;
+
+ int port;
+ bool reset_on_powerdown;
+};
+
struct intel_lvds_encoder {
struct intel_encoder base;

@@ -55,6 +69,9 @@ struct intel_lvds_encoder {
i915_reg_t reg;
u32 a3_power;

+ struct intel_lvds_pps init_pps;
+ u32 init_lvds_val;
+
struct intel_lvds_connector *attached_connector;
};

@@ -136,6 +153,72 @@ static void intel_lvds_get_config(struct intel_encoder *encoder,
pipe_config->base.adjusted_mode.crtc_clock = pipe_config->port_clock;
}

+static void intel_lvds_pps_get_hw_state(struct drm_i915_private *dev_priv,
+ struct intel_lvds_pps *pps)
+{
+ u32 val;
+
+ pps->reset_on_powerdown = I915_READ(PP_CONTROL(0)) & PANEL_POWER_RESET;
+
+ val = I915_READ(PP_ON_DELAYS(0));
+ pps->port = (val & PANEL_PORT_SELECT_MASK) >>
+ PANEL_PORT_SELECT_SHIFT;
+ pps->t1_t2 = (val & PANEL_POWER_UP_DELAY_MASK) >>
+ PANEL_POWER_UP_DELAY_SHIFT;
+ pps->t5 = (val & PANEL_LIGHT_ON_DELAY_MASK) >>
+ PANEL_LIGHT_ON_DELAY_SHIFT;
+
+ val = I915_READ(PP_OFF_DELAYS(0));
+ pps->t3 = (val & PANEL_POWER_DOWN_DELAY_MASK) >>
+ PANEL_POWER_DOWN_DELAY_SHIFT;
+ pps->tx = (val & PANEL_LIGHT_OFF_DELAY_MASK) >>
+ PANEL_LIGHT_OFF_DELAY_SHIFT;
+
+ val = I915_READ(PP_DIVISOR(0));
+ pps->divider = (val & PP_REFERENCE_DIVIDER_MASK) >>
+ PP_REFERENCE_DIVIDER_SHIFT;
+ /* Convert from 100ms to 100us units */
+ pps->t4 = ((val & PANEL_POWER_CYCLE_DELAY_MASK) >>
+ PANEL_POWER_CYCLE_DELAY_SHIFT) * 1000;
+
+ if (INTEL_INFO(dev_priv)->gen <= 4 &&
+ pps->t1_t2 == 0 && pps->t5 == 0 && pps->t3 == 0 && pps->tx == 0) {
+ DRM_DEBUG_KMS("Panel power timings uninitialized, "
+ "setting defaults\n");
+ /* Set T2 to 40ms and T5 to 200ms in 100 usec units */
+ pps->t1_t2 = 40 * 10;
+ pps->t5 = 200 * 10;
+ /* Set T3 to 35ms and Tx to 200ms in 100 usec units */
+ pps->t3 = 35 * 10;
+ pps->tx = 200 * 10;
+ }
+
+ DRM_DEBUG_DRIVER("LVDS PPS:t1+t2 %d t3 %d t4 %d t5 %d tx %d "
+ "divider %d port %d reset_on_powerdown %d\n",
+ pps->t1_t2, pps->t3, pps->t4, pps->t5, pps->tx,
+ pps->divider, pps->port, pps->reset_on_powerdown);
+}
+
+static void intel_lvds_pps_init_hw(struct drm_i915_private *dev_priv,
+ struct intel_lvds_pps *pps)
+{
+ u32 val;
+
+ val = I915_READ(PP_CONTROL(0));
+ WARN_ON((val & PANEL_UNLOCK_MASK) != PANEL_UNLOCK_REGS);
+ if (pps->reset_on_powerdown)
+ val |= PANEL_POWER_RESET;
+ I915_WRITE(PP_CONTROL(0), val);
+
+ I915_WRITE(PP_ON_DELAYS(0), (pps->port << PANEL_PORT_SELECT_SHIFT) |
+ (pps->t1_t2 << PANEL_POWER_UP_DELAY_SHIFT) |
+ (pps->t5 << PANEL_LIGHT_ON_DELAY_SHIFT));
+ I915_WRITE(PP_OFF_DELAYS(0), (pps->t3 << PANEL_POWER_DOWN_DELAY_SHIFT) |
+ (pps->tx << PANEL_LIGHT_OFF_DELAY_SHIFT));
+ I915_WRITE(PP_DIVISOR(0), (pps->divider << PP_REFERENCE_DIVIDER_SHIFT) |
+ ((pps->t4 / 1000) << PANEL_POWER_CYCLE_DELAY_SHIFT));
+}
+
static void intel_pre_enable_lvds(struct intel_encoder *encoder)
{
struct intel_lvds_encoder *lvds_encoder = to_lvds_encoder(&encoder->base);
@@ -154,7 +237,9 @@ static void intel_pre_enable_lvds(struct intel_encoder *encoder)
assert_pll_disabled(dev_priv, pipe);
}

- temp = I915_READ(lvds_encoder->reg);
+ intel_lvds_pps_init_hw(dev_priv, &lvds_encoder->init_pps);
+
+ temp = lvds_encoder->init_lvds_val;
temp |= LVDS_PORT_EN | LVDS_A0A2_CLKA_POWER_UP;

if (HAS_PCH_CPT(dev)) {
@@ -922,18 +1007,6 @@ void intel_lvds_init(struct drm_device *dev)
DRM_DEBUG_KMS("LVDS is not present in VBT, but enabled anyway\n");
}

- /* Set the Panel Power On/Off timings if uninitialized. */
- if (INTEL_INFO(dev_priv)->gen < 5 &&
- I915_READ(PP_ON_DELAYS(0)) == 0 && I915_READ(PP_OFF_DELAYS(0)) == 0) {
- /* Set T2 to 40ms and T5 to 200ms */
- I915_WRITE(PP_ON_DELAYS(0), 0x019007d0);
-
- /* Set T3 to 35ms and Tx to 200ms */
- I915_WRITE(PP_OFF_DELAYS(0), 0x015e07d0);
-
- DRM_DEBUG_KMS("Panel power timings uninitialized, setting defaults\n");
- }
-
lvds_encoder = kzalloc(sizeof(*lvds_encoder), GFP_KERNEL);
if (!lvds_encoder)
return;
@@ -999,6 +1072,10 @@ void intel_lvds_init(struct drm_device *dev)
dev->mode_config.scaling_mode_property,
DRM_MODE_SCALE_ASPECT);
intel_connector->panel.fitting_mode = DRM_MODE_SCALE_ASPECT;
+
+ intel_lvds_pps_get_hw_state(dev_priv, &lvds_encoder->init_pps);
+ lvds_encoder->init_lvds_val = lvds;
+
/*
* LVDS discovery:
* 1) check for EDID on DDC
--
2.5.0