[PATCH 05/18] drm/i915: Support for GuC interrupts

akash.goel
2016-08-15T14:36:28Z

From: Sagar Arun Kamble <sagar.a.kamble@intel.com>

There are certain types of interrupts which Host can receive from GuC.
GuC ukernel sends an interrupt to Host for certain events, like for
example retrieve/consume the logs generated by ukernel.
This patch adds support to receive interrupts from GuC but currently
enables & partially handles only the interrupt sent by GuC ukernel.
Future patches will add support for handling other interrupt types.

v2:
- Use common low level routines for PM IER/IIR programming (Chris)
- Rename interrupt functions to gen9_xxx from gen8_xxx (Chris)
- Replace disabling of wake ref asserts with rpm get/put (Chris)

v3:
- Update comments for more clarity. (Tvrtko)
- Remove the masking of GuC interrupt, which was kept masked till the
start of bottom half, its not really needed as there is only a
single instance of work item & wq is ordered. (Tvrtko)

v4:
- Rebase.
- Rename guc_events to pm_guc_events so as to be indicative of the
register/control block it is associated with. (Chris)
- Add handling for back to back log buffer flush interrupts.

v5:
- Move the read & clearing of register, containing Guc2Host message
bits, outside the irq spinlock. (Tvrtko)

v6:
- Move the log buffer flush interrupt related stuff to the following
patch so as to do only generic bits in this patch. (Tvrtko)
- Rebase.

Signed-off-by: Sagar Arun Kamble <sagar.a.kamble@intel.com>
Signed-off-by: Akash Goel <akash.goel@intel.com>
---
drivers/gpu/drm/i915/i915_drv.h | 1 +
drivers/gpu/drm/i915/i915_guc_submission.c | 5 +++
drivers/gpu/drm/i915/i915_irq.c | 63 ++++++++++++++++++++++++++++--
drivers/gpu/drm/i915/i915_reg.h | 11 ++++++
drivers/gpu/drm/i915/intel_drv.h | 3 ++
drivers/gpu/drm/i915/intel_guc.h | 3 ++
drivers/gpu/drm/i915/intel_guc_loader.c | 4 ++
7 files changed, 86 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index a187ea7..08553b9 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -1783,6 +1783,7 @@ struct drm_i915_private {
u32 pm_imr;
u32 pm_ier;
u32 pm_rps_events;
+ u32 pm_guc_events;
u32 pipestat_irq_mask[I915_MAX_PIPES];

struct i915_hotplug hotplug;
diff --git a/drivers/gpu/drm/i915/i915_guc_submission.c b/drivers/gpu/drm/i915/i915_guc_submission.c
index 34fb893..b062da6 100644
--- a/drivers/gpu/drm/i915/i915_guc_submission.c
+++ b/drivers/gpu/drm/i915/i915_guc_submission.c
@@ -1055,6 +1055,8 @@ int intel_guc_suspend(struct drm_device *dev)
if (guc->guc_fw.guc_fw_load_status != GUC_FIRMWARE_SUCCESS)
return 0;

+ gen9_disable_guc_interrupts(dev_priv);
+
ctx = dev_priv->kernel_context;

data[0] = HOST2GUC_ACTION_ENTER_S_STATE;
@@ -1081,6 +1083,9 @@ int intel_guc_resume(struct drm_device *dev)
if (guc->guc_fw.guc_fw_load_status != GUC_FIRMWARE_SUCCESS)
return 0;

+ if (i915.guc_log_level >= 0)
+ gen9_enable_guc_interrupts(dev_priv);
+
ctx = dev_priv->kernel_context;

data[0] = HOST2GUC_ACTION_EXIT_S_STATE;
diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index 83d708a..eb4774f 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -170,6 +170,7 @@ static void gen5_assert_iir_is_zero(struct drm_i915_private *dev_priv,
} while (0)

static void gen6_rps_irq_handler(struct drm_i915_private *dev_priv, u32 pm_iir);
+static void gen9_guc_irq_handler(struct drm_i915_private *dev_priv, u32 pm_iir);

/* For display hotplug interrupt */
static inline void
@@ -411,6 +412,38 @@ void gen6_disable_rps_interrupts(struct drm_i915_private *dev_priv)
gen6_reset_rps_interrupts(dev_priv);
}

+void gen9_reset_guc_interrupts(struct drm_i915_private *dev_priv)
+{
+ spin_lock_irq(&dev_priv->irq_lock);
+ gen6_reset_pm_iir(dev_priv, dev_priv->pm_guc_events);
+ spin_unlock_irq(&dev_priv->irq_lock);
+}
+
+void gen9_enable_guc_interrupts(struct drm_i915_private *dev_priv)
+{
+ spin_lock_irq(&dev_priv->irq_lock);
+ if (!dev_priv->guc.interrupts_enabled) {
+ WARN_ON_ONCE(I915_READ(gen6_pm_iir(dev_priv)) &
+ dev_priv->pm_guc_events);
+ dev_priv->guc.interrupts_enabled = true;
+ gen6_enable_pm_irq(dev_priv, dev_priv->pm_guc_events);
+ }
+ spin_unlock_irq(&dev_priv->irq_lock);
+}
+
+void gen9_disable_guc_interrupts(struct drm_i915_private *dev_priv)
+{
+ spin_lock_irq(&dev_priv->irq_lock);
+ dev_priv->guc.interrupts_enabled = false;
+
+ gen6_disable_pm_irq(dev_priv, dev_priv->pm_guc_events);
+
+ spin_unlock_irq(&dev_priv->irq_lock);
+ synchronize_irq(dev_priv->drm.irq);
+
+ gen9_reset_guc_interrupts(dev_priv);
+}
+
/**
* bdw_update_port_irq - update DE port interrupt
* @dev_priv: driver private
@@ -1339,11 +1372,13 @@ static irqreturn_t gen8_gt_irq_ack(struct drm_i915_private *dev_priv,
DRM_ERROR("The master control interrupt lied (GT3)!\n");
}

- if (master_ctl & GEN8_GT_PM_IRQ) {
+ if (master_ctl & (GEN8_GT_PM_IRQ | GEN8_GT_GUC_IRQ)) {
gt_iir[2] = I915_READ_FW(GEN8_GT_IIR(2));
- if (gt_iir[2] & dev_priv->pm_rps_events) {
+ if (gt_iir[2] & (dev_priv->pm_rps_events |
+ dev_priv->pm_guc_events)) {
I915_WRITE_FW(GEN8_GT_IIR(2),
- gt_iir[2] & dev_priv->pm_rps_events);
+ gt_iir[2] & (dev_priv->pm_rps_events |
+ dev_priv->pm_guc_events));
ret = IRQ_HANDLED;
} else
DRM_ERROR("The master control interrupt lied (PM)!\n");
@@ -1375,6 +1410,9 @@ static void gen8_gt_irq_handler(struct drm_i915_private *dev_priv,

if (gt_iir[2] & dev_priv->pm_rps_events)
gen6_rps_irq_handler(dev_priv, gt_iir[2]);
+
+ if (gt_iir[2] & dev_priv->pm_guc_events)
+ gen9_guc_irq_handler(dev_priv, gt_iir[2]);
}

static bool bxt_port_hotplug_long_detect(enum port port, u32 val)
@@ -1621,6 +1659,20 @@ static void gen6_rps_irq_handler(struct drm_i915_private *dev_priv, u32 pm_iir)
}
}

+static void gen9_guc_irq_handler(struct drm_i915_private *dev_priv, u32 gt_iir)
+{
+ bool interrupts_enabled;
+
+ if (gt_iir & GEN9_GUC_TO_HOST_INT_EVENT) {
+ spin_lock(&dev_priv->irq_lock);
+ interrupts_enabled = dev_priv->guc.interrupts_enabled;
+ spin_unlock(&dev_priv->irq_lock);
+ if (interrupts_enabled) {
+ /* TODO: Handle events for which GuC interrupted host */
+ }
+ }
+}
+
static bool intel_pipe_handle_vblank(struct drm_i915_private *dev_priv,
enum pipe pipe)
{
@@ -3722,7 +3774,7 @@ static void gen8_gt_irq_postinstall(struct drm_i915_private *dev_priv)
GEN8_IRQ_INIT_NDX(GT, 1, ~gt_interrupts[1], gt_interrupts[1]);
/*
* RPS interrupts will get enabled/disabled on demand when RPS itself
- * is enabled/disabled.
+ * is enabled/disabled. Same wil be the case for GuC interrupts.
*/
GEN8_IRQ_INIT_NDX(GT, 2, dev_priv->pm_imr, dev_priv->pm_ier);
GEN8_IRQ_INIT_NDX(GT, 3, ~gt_interrupts[3], gt_interrupts[3]);
@@ -4508,6 +4560,9 @@ void intel_irq_init(struct drm_i915_private *dev_priv)
INIT_WORK(&dev_priv->rps.work, gen6_pm_rps_work);
INIT_WORK(&dev_priv->l3_parity.error_work, ivybridge_parity_work);

+ if (HAS_GUC_SCHED(dev))
+ dev_priv->pm_guc_events = GEN9_GUC_TO_HOST_INT_EVENT;
+
/* Let's track the enabled rps events */
if (IS_VALLEYVIEW(dev_priv))
/* WaGsvRC0ResidencyMethod:vlv */
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index d4adf28..cab089a 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -6011,6 +6011,7 @@ enum {
#define GEN8_DE_PIPE_A_IRQ (1<<16)
#define GEN8_DE_PIPE_IRQ(pipe) (1<<(16+(pipe)))
#define GEN8_GT_VECS_IRQ (1<<6)
+#define GEN8_GT_GUC_IRQ (1<<5)
#define GEN8_GT_PM_IRQ (1<<4)
#define GEN8_GT_VCS2_IRQ (1<<3)
#define GEN8_GT_VCS1_IRQ (1<<2)
@@ -6022,6 +6023,16 @@ enum {
#define GEN8_GT_IIR(which) _MMIO(0x44308 + (0x10 * (which)))
#define GEN8_GT_IER(which) _MMIO(0x4430c + (0x10 * (which)))

+#define GEN9_GUC_TO_HOST_INT_EVENT (1<<31)
+#define GEN9_GUC_EXEC_ERROR_EVENT (1<<30)
+#define GEN9_GUC_DISPLAY_EVENT (1<<29)
+#define GEN9_GUC_SEMA_SIGNAL_EVENT (1<<28)
+#define GEN9_GUC_IOMMU_MSG_EVENT (1<<27)
+#define GEN9_GUC_DB_RING_EVENT (1<<26)
+#define GEN9_GUC_DMA_DONE_EVENT (1<<25)
+#define GEN9_GUC_FATAL_ERROR_EVENT (1<<24)
+#define GEN9_GUC_NOTIFICATION_EVENT (1<<23)
+
#define GEN8_RCS_IRQ_SHIFT 0
#define GEN8_BCS_IRQ_SHIFT 16
#define GEN8_VCS1_IRQ_SHIFT 0
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index 9b99a84..f7f16ac 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -1120,6 +1120,9 @@ void gen8_irq_power_well_post_enable(struct drm_i915_private *dev_priv,
unsigned int pipe_mask);
void gen8_irq_power_well_pre_disable(struct drm_i915_private *dev_priv,
unsigned int pipe_mask);
+void gen9_reset_guc_interrupts(struct drm_i915_private *dev_priv);
+void gen9_enable_guc_interrupts(struct drm_i915_private *dev_priv);
+void gen9_disable_guc_interrupts(struct drm_i915_private *dev_priv);

/* intel_crt.c */
void intel_crt_init(struct drm_device *dev);
diff --git a/drivers/gpu/drm/i915/intel_guc.h b/drivers/gpu/drm/i915/intel_guc.h
index d32023c..1fc63fe 100644
--- a/drivers/gpu/drm/i915/intel_guc.h
+++ b/drivers/gpu/drm/i915/intel_guc.h
@@ -130,6 +130,9 @@ struct intel_guc {
struct intel_guc_fw guc_fw;
struct intel_guc_log log;

+ /* GuC2Host interrupt related state */
+ bool interrupts_enabled;
+
struct i915_vma *ads_vma;
struct i915_vma *ctx_pool_vma;
struct ida ctx_ids;
diff --git a/drivers/gpu/drm/i915/intel_guc_loader.c b/drivers/gpu/drm/i915/intel_guc_loader.c
index 6fd24d9..ef35e99 100644
--- a/drivers/gpu/drm/i915/intel_guc_loader.c
+++ b/drivers/gpu/drm/i915/intel_guc_loader.c
@@ -464,6 +464,7 @@ int intel_guc_setup(struct drm_device *dev)
}

direct_interrupts_to_host(dev_priv);
+ gen9_reset_guc_interrupts(dev_priv);

guc_fw->guc_fw_load_status = GUC_FIRMWARE_PENDING;

@@ -510,6 +511,9 @@ int intel_guc_setup(struct drm_device *dev)
intel_guc_fw_status_repr(guc_fw->guc_fw_load_status));

if (i915.enable_guc_submission) {
+ if (i915.guc_log_level >= 0)
+ gen9_enable_guc_interrupts(dev_priv);
+
err = i915_guc_submission_enable(dev_priv);
if (err)
goto fail;
--
1.9.2