[PATCH v3 5/7] drm/i915: Reorganize the DSI enable/disable sequence

Shobhit Kumar
2013-12-10T06:45:16Z

Basically ULPS handling during enable/disable has been moved to
pre_enable and post_disable phases. PLL and panel power disable
also has been moved to post_disable phase. The ULPS entry/exit
sequneces as suggested by HW team is as follows -

During enable time -
set DEVICE_READY --> Clear DEVICE_READY --> set DEVICE_READY

And during disable time to flush all FIFOs -
set ENTER_SLEEP --> EXIT_SLEEP --> ENTER_SLEEP

Also during disbale sequnece sub-encoder disable is moved to the end
after port is disabled.

v2: Based on comments from Ville
- Detailed epxlaination in the commit messgae
- Moved parameter changes out into another patch
- Backlight enabling will be a new patch

v3: Updated as per Jani's comments
- Removed the I915_WRITE_BITS as it is not needed
- Moved panel_reset and send_otp_cmds hooks to dsi_pre_enable
- Moved disable_panel_power hook to dsi_post_disable
- Replace hardcoding with AFE_LATCHOUT

Signed-off-by: Yogesh Mohan Marimuthu <yogesh.mohan.marimuthu@intel.com>
Signed-off-by: Shobhit Kumar <shobhit.kumar@intel.com>
---
drivers/gpu/drm/i915/intel_dsi.c | 110 +++++++++++++++++++++++++++------------
drivers/gpu/drm/i915/intel_dsi.h | 2 +
2 files changed, 79 insertions(+), 33 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_dsi.c b/drivers/gpu/drm/i915/intel_dsi.c
index 1016e7b..01b9f3a 100644
--- a/drivers/gpu/drm/i915/intel_dsi.c
+++ b/drivers/gpu/drm/i915/intel_dsi.c
@@ -101,46 +101,57 @@ static void intel_dsi_pre_pll_enable(struct intel_encoder *encoder)
vlv_enable_dsi_pll(encoder);
}

-static void intel_dsi_pre_enable(struct intel_encoder *encoder)
+void intel_dsi_device_ready(struct intel_encoder *encoder)
{
+ struct drm_i915_private *dev_priv = encoder->base.dev->dev_private;
+ struct intel_crtc *intel_crtc = to_intel_crtc(encoder->base.crtc);
+ int pipe = intel_crtc->pipe;
+ u32 val;
+
DRM_DEBUG_KMS("\n");
-}

-static void intel_dsi_enable(struct intel_encoder *encoder)
+ val = I915_READ(MIPI_PORT_CTRL(pipe));
+ I915_WRITE(MIPI_PORT_CTRL(pipe), val | LP_OUTPUT_HOLD);
+ usleep_range(1000, 1500);
+ I915_WRITE(MIPI_DEVICE_READY(pipe), DEVICE_READY | ULPS_STATE_EXIT);
+ usleep_range(2000, 2500);
+ I915_WRITE(MIPI_DEVICE_READY(pipe), DEVICE_READY);
+ usleep_range(2000, 2500);
+ I915_WRITE(MIPI_DEVICE_READY(pipe), 0x00);
+ usleep_range(2000, 2500);
+ I915_WRITE(MIPI_DEVICE_READY(pipe), DEVICE_READY);
+ usleep_range(2000, 2500);
+}
+static void intel_dsi_pre_enable(struct intel_encoder *encoder)
{
- struct drm_i915_private *dev_priv = encoder->base.dev->dev_private;
- struct intel_crtc *intel_crtc = to_intel_crtc(encoder->base.crtc);
struct intel_dsi *intel_dsi = enc_to_intel_dsi(&encoder->base);
- int pipe = intel_crtc->pipe;
- u32 temp;

DRM_DEBUG_KMS("\n");

if (intel_dsi->dev.dev_ops->panel_reset)
intel_dsi->dev.dev_ops->panel_reset(&intel_dsi->dev);

- temp = I915_READ(MIPI_DEVICE_READY(pipe));
- if ((temp & DEVICE_READY) == 0) {
- temp &= ~ULPS_STATE_MASK;
- I915_WRITE(MIPI_DEVICE_READY(pipe), temp | DEVICE_READY);
- } else if (temp & ULPS_STATE_MASK) {
- temp &= ~ULPS_STATE_MASK;
- I915_WRITE(MIPI_DEVICE_READY(pipe), temp | ULPS_STATE_EXIT);
- /*
- * We need to ensure that there is a minimum of 1 ms time
- * available before clearing the UPLS exit state.
- */
- msleep(2);
- I915_WRITE(MIPI_DEVICE_READY(pipe), temp);
- }
+ /* put device in ready state */
+ intel_dsi_device_ready(encoder);

if (intel_dsi->dev.dev_ops->send_otp_cmds)
intel_dsi->dev.dev_ops->send_otp_cmds(&intel_dsi->dev);
+}
+
+static void intel_dsi_enable(struct intel_encoder *encoder)
+{
+ struct drm_device *dev = encoder->base.dev;
+ struct drm_i915_private *dev_priv = dev->dev_private;
+ struct intel_crtc *intel_crtc = to_intel_crtc(encoder->base.crtc);
+ struct intel_dsi *intel_dsi = enc_to_intel_dsi(&encoder->base);
+ int pipe = intel_crtc->pipe;
+ u32 temp;
+
+ DRM_DEBUG_KMS("\n");

if (is_cmd_mode(intel_dsi))
I915_WRITE(MIPI_MAX_RETURN_PKT_SIZE(pipe), 8 * 4);
-
- if (is_vid_mode(intel_dsi)) {
+ else {
msleep(20); /* XXX */
dpi_send_cmd(intel_dsi, TURN_ON);
msleep(100);
@@ -157,7 +168,8 @@ static void intel_dsi_enable(struct intel_encoder *encoder)

static void intel_dsi_disable(struct intel_encoder *encoder)
{
- struct drm_i915_private *dev_priv = encoder->base.dev->dev_private;
+ struct drm_device *dev = encoder->base.dev;
+ struct drm_i915_private *dev_priv = dev->dev_private;
struct intel_crtc *intel_crtc = to_intel_crtc(encoder->base.crtc);
struct intel_dsi *intel_dsi = enc_to_intel_dsi(&encoder->base);
int pipe = intel_crtc->pipe;
@@ -165,8 +177,6 @@ static void intel_dsi_disable(struct intel_encoder *encoder)

DRM_DEBUG_KMS("\n");

- intel_dsi->dev.dev_ops->disable(&intel_dsi->dev);
-
if (is_vid_mode(intel_dsi)) {
dpi_send_cmd(intel_dsi, SHUTDOWN);
msleep(10);
@@ -179,20 +189,54 @@ static void intel_dsi_disable(struct intel_encoder *encoder)
msleep(2);
}

- temp = I915_READ(MIPI_DEVICE_READY(pipe));
- if (temp & DEVICE_READY) {
- temp &= ~DEVICE_READY;
- temp &= ~ULPS_STATE_MASK;
- I915_WRITE(MIPI_DEVICE_READY(pipe), temp);
- }
+ /* if disable packets are sent before sending shutdown packet then in
+ * some next enable sequence send turn on packet error is observed */
+ if (intel_dsi->dev.dev_ops->disable)
+ intel_dsi->dev.dev_ops->disable(&intel_dsi->dev);
}

-static void intel_dsi_post_disable(struct intel_encoder *encoder)
+void intel_dsi_clear_device_ready(struct intel_encoder *encoder)
{
+ struct drm_i915_private *dev_priv = encoder->base.dev->dev_private;
+ struct intel_crtc *intel_crtc = to_intel_crtc(encoder->base.crtc);
+ int pipe = intel_crtc->pipe;
+ u32 val;
+
DRM_DEBUG_KMS("\n");

+ I915_WRITE(MIPI_DEVICE_READY(pipe), ULPS_STATE_ENTER);
+ usleep_range(2000, 2500);
+
+ I915_WRITE(MIPI_DEVICE_READY(pipe), ULPS_STATE_EXIT);
+ usleep_range(2000, 2500);
+
+ I915_WRITE(MIPI_DEVICE_READY(pipe), ULPS_STATE_ENTER);
+ usleep_range(2000, 2500);
+
+ val = I915_READ(MIPI_PORT_CTRL(pipe));
+ I915_WRITE(MIPI_PORT_CTRL(pipe), val & ~LP_OUTPUT_HOLD);
+ usleep_range(1000, 1500);
+
+ if (wait_for(((I915_READ(MIPI_PORT_CTRL(pipe)) & AFE_LATCHOUT)
+ == 0x00000), 30))
+ DRM_ERROR("DSI LP not going Low\n");
+
+ I915_WRITE(MIPI_DEVICE_READY(pipe), 0x00);
+ usleep_range(2000, 2500);
+
vlv_disable_dsi_pll(encoder);
}
+static void intel_dsi_post_disable(struct intel_encoder *encoder)
+{
+ struct intel_dsi *intel_dsi = enc_to_intel_dsi(&encoder->base);
+
+ DRM_DEBUG_KMS("\n");
+
+ intel_dsi_clear_device_ready(encoder);
+
+ if (intel_dsi->dev.dev_ops->disable_panel_power)
+ intel_dsi->dev.dev_ops->disable_panel_power(&intel_dsi->dev);
+}

static bool intel_dsi_get_hw_state(struct intel_encoder *encoder,
enum pipe *pipe)
diff --git a/drivers/gpu/drm/i915/intel_dsi.h b/drivers/gpu/drm/i915/intel_dsi.h
index 14509d6..387dfe1 100644
--- a/drivers/gpu/drm/i915/intel_dsi.h
+++ b/drivers/gpu/drm/i915/intel_dsi.h
@@ -41,6 +41,8 @@ struct intel_dsi_dev_ops {

void (*panel_reset)(struct intel_dsi_device *dsi);

+ void (*disable_panel_power)(struct intel_dsi_device *dsi);
+
/* one time programmable commands if needed */
void (*send_otp_cmds)(struct intel_dsi_device *dsi);

--
1.8.3.2