[PATCH v11 5/5] drm/msm/dp: Add Display Port HPD feature

From: Tanmay Shah
Date: Tue Aug 18 2020 - 01:12:42 EST


Configure HPD registers in DP controller and
enable HPD interrupt.

Add interrupt to handle HPD connect and disconnect events.

Changes in v8: None

Signed-off-by: Tanmay Shah <tanmay@xxxxxxxxxxxxxx>
---
drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c | 18 ++++
drivers/gpu/drm/msm/dp/dp_catalog.c | 63 ++++++++------
drivers/gpu/drm/msm/dp/dp_catalog.h | 5 +-
drivers/gpu/drm/msm/dp/dp_ctrl.c | 1 -
drivers/gpu/drm/msm/dp/dp_display.c | 108 ++++++++++++++++++++++--
drivers/gpu/drm/msm/dp/dp_reg.h | 12 +++
drivers/gpu/drm/msm/msm_drv.h | 6 ++
7 files changed, 180 insertions(+), 33 deletions(-)

diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
index 62bc33cb0d3a..5e977d5ff341 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
@@ -752,6 +752,23 @@ static void dpu_irq_preinstall(struct msm_kms *kms)
dpu_core_irq_preinstall(dpu_kms);
}

+static int dpu_irq_postinstall(struct msm_kms *kms)
+{
+ struct msm_drm_private *priv;
+ struct dpu_kms *dpu_kms = to_dpu_kms(kms);
+
+ if (!dpu_kms || !dpu_kms->dev)
+ return -EINVAL;
+
+ priv = dpu_kms->dev->dev_private;
+ if (!priv)
+ return -EINVAL;
+
+ msm_dp_irq_postinstall(priv->dp);
+
+ return 0;
+}
+
static void dpu_irq_uninstall(struct msm_kms *kms)
{
struct dpu_kms *dpu_kms = to_dpu_kms(kms);
@@ -762,6 +779,7 @@ static void dpu_irq_uninstall(struct msm_kms *kms)
static const struct msm_kms_funcs kms_funcs = {
.hw_init = dpu_kms_hw_init,
.irq_preinstall = dpu_irq_preinstall,
+ .irq_postinstall = dpu_irq_postinstall,
.irq_uninstall = dpu_irq_uninstall,
.irq = dpu_irq,
.enable_commit = dpu_kms_enable_commit,
diff --git a/drivers/gpu/drm/msm/dp/dp_catalog.c b/drivers/gpu/drm/msm/dp/dp_catalog.c
index e506e0756e92..d186424044b1 100644
--- a/drivers/gpu/drm/msm/dp/dp_catalog.c
+++ b/drivers/gpu/drm/msm/dp/dp_catalog.c
@@ -17,7 +17,6 @@
#define POLLING_SLEEP_US 1000
#define POLLING_TIMEOUT_US 10000

-#define REFTIMER_DEFAULT_VALUE 0x20000
#define SCRAMBLER_RESET_COUNT_VALUE 0xFC

#define DP_INTERRUPT_STATUS_ACK_SHIFT 1
@@ -731,35 +730,51 @@ void dp_catalog_ctrl_enable_irq(struct dp_catalog *dp_catalog,
}
}

-void dp_catalog_ctrl_hpd_config(struct dp_catalog *dp_catalog, bool en)
+void dp_catalog_hpd_config_intr(struct dp_catalog *dp_catalog,
+ u32 intr_mask, bool en)
{
struct dp_catalog_private *catalog = container_of(dp_catalog,
struct dp_catalog_private, dp_catalog);

- if (en) {
- u32 reftimer = dp_read_aux(catalog, REG_DP_DP_HPD_REFTIMER);
+ u32 config = dp_read_aux(catalog, REG_DP_DP_HPD_INT_MASK);

- dp_write_aux(catalog, REG_DP_DP_HPD_INT_ACK,
- DP_DP_HPD_PLUG_INT_ACK |
- DP_DP_IRQ_HPD_INT_ACK |
- DP_DP_HPD_REPLUG_INT_ACK |
- DP_DP_HPD_UNPLUG_INT_ACK);
- dp_write_aux(catalog, REG_DP_DP_HPD_INT_MASK,
- DP_DP_HPD_PLUG_INT_MASK |
- DP_DP_IRQ_HPD_INT_MASK |
- DP_DP_HPD_REPLUG_INT_MASK |
- DP_DP_HPD_UNPLUG_INT_MASK);
+ config = (en ? config | intr_mask : config & ~intr_mask);

- /* Configure REFTIMER */
- reftimer |= REFTIMER_DEFAULT_VALUE;
- dp_write_aux(catalog, REG_DP_DP_HPD_REFTIMER, reftimer);
- /* Enable HPD */
- dp_write_aux(catalog, REG_DP_DP_HPD_CTRL,
- DP_DP_HPD_CTRL_HPD_EN);
- } else {
- /* Disable HPD */
- dp_write_aux(catalog, REG_DP_DP_HPD_CTRL, 0x0);
- }
+ dp_write_aux(catalog, REG_DP_DP_HPD_INT_MASK,
+ config & DP_DP_HPD_INT_MASK);
+}
+
+void dp_catalog_ctrl_hpd_config(struct dp_catalog *dp_catalog)
+{
+ struct dp_catalog_private *catalog = container_of(dp_catalog,
+ struct dp_catalog_private, dp_catalog);
+
+ u32 reftimer = dp_read_aux(catalog, REG_DP_DP_HPD_REFTIMER);
+
+ /* enable HPD interrupts */
+ dp_catalog_hpd_config_intr(dp_catalog,
+ DP_DP_HPD_PLUG_INT_MASK | DP_DP_IRQ_HPD_INT_MASK
+ | DP_DP_HPD_UNPLUG_INT_MASK, true);
+
+ /* Configure REFTIMER and enable it */
+ reftimer |= DP_DP_HPD_REFTIMER_ENABLE;
+ dp_write_aux(catalog, REG_DP_DP_HPD_REFTIMER, reftimer);
+
+ /* Enable HPD */
+ dp_write_aux(catalog, REG_DP_DP_HPD_CTRL, DP_DP_HPD_CTRL_HPD_EN);
+}
+
+u32 dp_catalog_hpd_get_intr_status(struct dp_catalog *dp_catalog)
+{
+ struct dp_catalog_private *catalog = container_of(dp_catalog,
+ struct dp_catalog_private, dp_catalog);
+ int isr = 0;
+
+ isr = dp_read_aux(catalog, REG_DP_DP_HPD_INT_STATUS);
+ dp_write_aux(catalog, REG_DP_DP_HPD_INT_ACK,
+ (isr & DP_DP_HPD_INT_MASK));
+
+ return isr;
}

int dp_catalog_ctrl_get_interrupt(struct dp_catalog *dp_catalog)
diff --git a/drivers/gpu/drm/msm/dp/dp_catalog.h b/drivers/gpu/drm/msm/dp/dp_catalog.h
index 4cf9ad4206cc..bcd381bfc9cd 100644
--- a/drivers/gpu/drm/msm/dp/dp_catalog.h
+++ b/drivers/gpu/drm/msm/dp/dp_catalog.h
@@ -75,7 +75,10 @@ void dp_catalog_ctrl_reset(struct dp_catalog *dp_catalog);
void dp_catalog_ctrl_usb_reset(struct dp_catalog *dp_catalog, bool flip);
bool dp_catalog_ctrl_mainlink_ready(struct dp_catalog *dp_catalog);
void dp_catalog_ctrl_enable_irq(struct dp_catalog *dp_catalog, bool enable);
-void dp_catalog_ctrl_hpd_config(struct dp_catalog *dp_catalog, bool enable);
+void dp_catalog_hpd_config_intr(struct dp_catalog *dp_catalog,
+ u32 intr_mask, bool en);
+void dp_catalog_ctrl_hpd_config(struct dp_catalog *dp_catalog);
+u32 dp_catalog_hpd_get_intr_status(struct dp_catalog *dp_catalog);
void dp_catalog_ctrl_phy_reset(struct dp_catalog *dp_catalog);
void dp_catalog_ctrl_phy_lane_cfg(struct dp_catalog *dp_catalog, bool flipped,
u8 lane_cnt);
diff --git a/drivers/gpu/drm/msm/dp/dp_ctrl.c b/drivers/gpu/drm/msm/dp/dp_ctrl.c
index 9a06cbf40af1..ae07e43b541b 100644
--- a/drivers/gpu/drm/msm/dp/dp_ctrl.c
+++ b/drivers/gpu/drm/msm/dp/dp_ctrl.c
@@ -1563,7 +1563,6 @@ int dp_ctrl_on(struct dp_ctrl *dp_ctrl)
rate = ctrl->panel->link_info.rate;

dp_power_clk_enable(ctrl->power, DP_CORE_PM, true);
- dp_catalog_ctrl_hpd_config(ctrl->catalog, true);

if (ctrl->link->sink_request & DP_TEST_LINK_PHY_TEST_PATTERN) {
DRM_DEBUG_DP("using phy test link parameters\n");
diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/dp_display.c
index 86c958b21c97..36b6ee4131bb 100644
--- a/drivers/gpu/drm/msm/dp/dp_display.c
+++ b/drivers/gpu/drm/msm/dp/dp_display.c
@@ -17,6 +17,7 @@
#include "dp_power.h"
#include "dp_catalog.h"
#include "dp_aux.h"
+#include "dp_reg.h"
#include "dp_link.h"
#include "dp_panel.h"
#include "dp_ctrl.h"
@@ -36,6 +37,7 @@ struct dp_display_private {
bool power_on;
bool hpd_irq_on;
bool audio_supported;
+ atomic_t hpd_isr_status;

struct platform_device *pdev;
struct dentry *root;
@@ -54,6 +56,8 @@ struct dp_display_private {
struct dp_usbpd_cb usbpd_cb;
struct dp_display_mode dp_mode;
struct msm_dp dp_display;
+
+ struct delayed_work config_hpd_work;
};

static const struct of_device_id dp_dt_match[] = {
@@ -64,6 +68,20 @@ static const struct of_device_id dp_dt_match[] = {
static irqreturn_t dp_display_irq(int irq, void *dev_id)
{
struct dp_display_private *dp = dev_id;
+ irqreturn_t ret = IRQ_HANDLED;
+ u32 hpd_isr_status;
+
+ if (!dp) {
+ DRM_ERROR("invalid data\n");
+ return IRQ_NONE;
+ }
+
+ hpd_isr_status = dp_catalog_hpd_get_intr_status(dp->catalog);
+
+ if (hpd_isr_status & DP_DP_HPD_INT_MASK) {
+ atomic_set(&dp->hpd_isr_status, hpd_isr_status);
+ ret = IRQ_WAKE_THREAD;
+ }

/* DP controller isr */
dp_ctrl_isr(dp->ctrl);
@@ -71,6 +89,54 @@ static irqreturn_t dp_display_irq(int irq, void *dev_id)
/* DP aux isr */
dp_aux_isr(dp->aux);

+ return ret;
+}
+
+static irqreturn_t dp_display_hpd_isr_work(int irq, void *data)
+{
+ struct dp_display_private *dp;
+ struct dp_usbpd *hpd;
+ u32 isr = 0;
+
+ dp = (struct dp_display_private *)data;
+ if (!dp)
+ return IRQ_NONE;
+
+ isr = atomic_read(&dp->hpd_isr_status);
+
+ /* reset to default */
+ atomic_set(&dp->hpd_isr_status, 0);
+
+ hpd = dp->usbpd;
+ if (!hpd)
+ return IRQ_NONE;
+
+ if (isr & DP_DP_HPD_PLUG_INT_MASK &&
+ isr & DP_DP_HPD_STATE_STATUS_CONNECTED) {
+ hpd->hpd_high = 1;
+ dp->usbpd_cb.configure(&dp->pdev->dev);
+ } else if (isr & DP_DP_HPD_UNPLUG_INT_MASK &&
+ (isr & DP_DP_HPD_STATE_STATUS_MASK) ==
+ DP_DP_HPD_STATE_STATUS_DISCONNECTED) {
+
+ /* disable HPD plug interrupt until disconnect is done
+ */
+ dp_catalog_hpd_config_intr(dp->catalog,
+ DP_DP_HPD_PLUG_INT_MASK | DP_DP_IRQ_HPD_INT_MASK,
+ false);
+
+ hpd->hpd_high = 0;
+
+ /* We don't need separate work for disconnect as
+ * connect/attention interrupts are disabled
+ */
+ dp->usbpd_cb.disconnect(&dp->pdev->dev);
+
+ dp_catalog_hpd_config_intr(dp->catalog,
+ DP_DP_HPD_PLUG_INT_MASK | DP_DP_IRQ_HPD_INT_MASK,
+ true);
+ }
+
return IRQ_HANDLED;
}

@@ -212,8 +278,6 @@ static int dp_display_process_hpd_high(struct dp_display_private *dp)
int rc = 0;
struct edid *edid;

- dp_aux_init(dp->aux);
-
if (dp->link->psm_enabled)
goto notify;

@@ -270,10 +334,6 @@ static void dp_display_host_deinit(struct dp_display_private *dp)
return;
}

- dp_ctrl_host_deinit(dp->ctrl);
- dp_aux_deinit(dp->aux);
- dp_power_deinit(dp->power);
- disable_irq(dp->irq);
dp->core_initialized = false;
}

@@ -630,7 +690,8 @@ int dp_display_request_irq(struct msm_dp *dp_display)
return rc;
}

- rc = devm_request_irq(&dp->pdev->dev, dp->irq, dp_display_irq,
+ rc = devm_request_threaded_irq(&dp->pdev->dev, dp->irq,
+ dp_display_irq, dp_display_hpd_isr_work,
IRQF_TRIGGER_HIGH, "dp_display_isr", dp);
if (rc < 0) {
DRM_ERROR("failed to request IRQ%u: %d\n",
@@ -800,6 +861,39 @@ void __exit msm_dp_unregister(void)
platform_driver_unregister(&dp_display_driver);
}

+static void dp_display_config_hpd_work(struct work_struct *work)
+{
+ struct dp_display_private *dp;
+ struct delayed_work *dw = to_delayed_work(work);
+
+ dp = container_of(dw, struct dp_display_private, config_hpd_work);
+
+ dp_display_host_init(dp);
+ dp_catalog_ctrl_hpd_config(dp->catalog);
+
+ /* set default to 0 */
+ atomic_set(&dp->hpd_isr_status, 0);
+
+ /* Enable interrupt first time
+ * we are leaving dp clocks on during disconnect
+ * and never disable interrupt
+ */
+ enable_irq(dp->irq);
+}
+
+void msm_dp_irq_postinstall(struct msm_dp *dp_display)
+{
+ struct dp_display_private *dp;
+
+ if (!dp_display)
+ return;
+
+ dp = container_of(dp_display, struct dp_display_private, dp_display);
+
+ INIT_DELAYED_WORK(&dp->config_hpd_work, dp_display_config_hpd_work);
+ queue_delayed_work(system_wq, &dp->config_hpd_work, HZ * 10);
+}
+
int msm_dp_modeset_init(struct msm_dp *dp_display, struct drm_device *dev,
struct drm_encoder *encoder)
{
diff --git a/drivers/gpu/drm/msm/dp/dp_reg.h b/drivers/gpu/drm/msm/dp/dp_reg.h
index ad6f1760f893..6b3e297e4e04 100644
--- a/drivers/gpu/drm/msm/dp/dp_reg.h
+++ b/drivers/gpu/drm/msm/dp/dp_reg.h
@@ -54,10 +54,22 @@
#define DP_DP_IRQ_HPD_INT_MASK (0x00000002)
#define DP_DP_HPD_REPLUG_INT_MASK (0x00000004)
#define DP_DP_HPD_UNPLUG_INT_MASK (0x00000008)
+#define DP_DP_HPD_INT_MASK (DP_DP_HPD_PLUG_INT_MASK | \
+ DP_DP_IRQ_HPD_INT_MASK | \
+ DP_DP_HPD_REPLUG_INT_MASK | \
+ DP_DP_HPD_UNPLUG_INT_MASK)
+#define DP_DP_HPD_STATE_STATUS_CONNECTED (0x40000000)
+#define DP_DP_HPD_STATE_STATUS_PENDING (0x20000000)
+#define DP_DP_HPD_STATE_STATUS_DISCONNECTED (0x00000000)
+#define DP_DP_HPD_STATE_STATUS_MASK (0xE0000000)

#define REG_DP_DP_HPD_REFTIMER (0x00000018)
+#define DP_DP_HPD_REFTIMER_ENABLE (1 << 16)
+
#define REG_DP_DP_HPD_EVENT_TIME_0 (0x0000001C)
#define REG_DP_DP_HPD_EVENT_TIME_1 (0x00000020)
+#define DP_DP_HPD_EVENT_TIME_0_VAL (0x3E800FA)
+#define DP_DP_HPD_EVENT_TIME_1_VAL (0x1F407D0)

#define REG_DP_AUX_CTRL (0x00000030)
#define DP_AUX_CTRL_ENABLE (0x00000001)
diff --git a/drivers/gpu/drm/msm/msm_drv.h b/drivers/gpu/drm/msm/msm_drv.h
index 9360331a8f39..b4b213e57f99 100644
--- a/drivers/gpu/drm/msm/msm_drv.h
+++ b/drivers/gpu/drm/msm/msm_drv.h
@@ -390,6 +390,7 @@ int msm_dp_display_disable(struct msm_dp *dp, struct drm_encoder *encoder);
void msm_dp_display_mode_set(struct msm_dp *dp, struct drm_encoder *encoder,
struct drm_display_mode *mode,
struct drm_display_mode *adjusted_mode);
+void msm_dp_irq_postinstall(struct msm_dp *dp_display);

#else
static inline int __init msm_dp_register(void)
@@ -421,6 +422,11 @@ static inline void msm_dp_display_mode_set(struct msm_dp *dp,
struct drm_display_mode *adjusted_mode)
{
}
+
+static inline void msm_dp_irq_postinstall(struct msm_dp *dp_display)
+{
+}
+
#endif

void __init msm_mdp_register(void);
--
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