Upon enabling histogram an interrupt is trigerred after the generation
of the statistics. This patch registers the histogram interrupt and
handles the interrupt.
v2: Added intel_crtc backpointer to intel_histogram struct (Jani)
Removed histogram_wq and instead use dev_priv->unodered_eq (Jani)
v3: Replaced drm_i915_private with intel_display (Suraj)
Refactored the histogram read code (Jani)
v4: Rebased after addressing comments on patch 1
Signed-off-by: Arun R Murthy <arun.r.murthy@xxxxxxxxx>
---
.../gpu/drm/i915/display/intel_display_irq.c | 6 +-
.../gpu/drm/i915/display/intel_histogram.c | 93 +++++++++++++++++++
.../gpu/drm/i915/display/intel_histogram.h | 3 +
drivers/gpu/drm/i915/i915_reg.h | 5 +-
4 files changed, 104 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/i915/display/intel_display_irq.c b/drivers/gpu/drm/i915/display/intel_display_irq.c
index f0d3bdb5fc60..cb60c9db4418 100644
--- a/drivers/gpu/drm/i915/display/intel_display_irq.c
+++ b/drivers/gpu/drm/i915/display/intel_display_irq.c
@@ -20,6 +20,7 @@
#include "intel_fdi_regs.h"
#include "intel_fifo_underrun.h"
#include "intel_gmbus.h"
+#include "intel_histogram.h"
#include "intel_hotplug_irq.h"
#include "intel_pipe_crc_regs.h"
#include "intel_pmdemand.h"
@@ -1179,6 +1180,9 @@ void gen8_de_irq_handler(struct drm_i915_private *dev_priv, u32 master_ctl)
if (iir & GEN8_PIPE_FIFO_UNDERRUN)
intel_cpu_fifo_underrun_irq_handler(dev_priv, pipe);
+ if (iir & GEN9_PIPE_HISTOGRAM_EVENT)
+ intel_histogram_irq_handler(display, pipe);
+
fault_errors = iir & gen8_de_pipe_fault_mask(dev_priv);
if (fault_errors)
drm_err_ratelimited(&dev_priv->drm,
@@ -1764,7 +1768,7 @@ void gen8_de_irq_postinstall(struct drm_i915_private *dev_priv)
struct intel_uncore *uncore = &dev_priv->uncore;
u32 de_pipe_masked = gen8_de_pipe_fault_mask(dev_priv) |
- GEN8_PIPE_CDCLK_CRC_DONE;
+ GEN8_PIPE_CDCLK_CRC_DONE | GEN9_PIPE_HISTOGRAM_EVENT;
u32 de_pipe_enables;
u32 de_port_masked = gen8_de_port_aux_mask(dev_priv);
u32 de_port_enables;
diff --git a/drivers/gpu/drm/i915/display/intel_histogram.c b/drivers/gpu/drm/i915/display/intel_histogram.c
index e751977fc6f7..16f29923ef10 100644
--- a/drivers/gpu/drm/i915/display/intel_histogram.c
+++ b/drivers/gpu/drm/i915/display/intel_histogram.c
@@ -18,6 +18,8 @@
#define HISTOGRAM_GUARDBAND_THRESHOLD_DEFAULT 300 // 3.0% of the pipe's current pixel count.
#define HISTOGRAM_GUARDBAND_PRECISION_FACTOR 10000 // Precision factor for threshold guardband.
#define HISTOGRAM_DEFAULT_GUARDBAND_DELAY 0x04
+#define HISTOGRAM_BIN_READ_RETRY_COUNT 5
+#define HISTOGRAM_BIN_READ_DELAY 2
struct intel_histogram {
struct intel_crtc *crtc;
@@ -27,6 +29,92 @@ struct intel_histogram {
u32 bin_data[HISTOGRAM_BIN_COUNT];
};
+static bool intel_histogram_get_data(struct intel_crtc *intel_crtc)
+{
+ struct intel_display *display = to_intel_display(intel_crtc);
+ struct intel_histogram *histogram = intel_crtc->histogram;
+ u8 index, retry_count;
+ u32 dpstbin;
+
+ index = 0;
+ retry_count = 0;
+
+ while (index < HISTOGRAM_BIN_COUNT) {
+ dpstbin = intel_de_read(display, DPST_BIN(intel_crtc->pipe));
+ if (!(dpstbin & DPST_BIN_BUSY)) {
+ histogram->bin_data[index] = dpstbin & DPST_BIN_DATA_MASK;
+ index++;
+ } else {
+ /*
+ * If DPST_BIN busy bit is set, then set the
+ * DPST_CTL bin reg index to 0 and proceed
+ * from beginning.
+ */
+ retry_count++;
+ if (retry_count > HISTOGRAM_BIN_READ_RETRY_COUNT) {
+ drm_err(display->drm, "Histogram bin read failed with max retry\n");
+ return false;
+ }
+ /* Add a delay before retrying */
+ fsleep(HISTOGRAM_BIN_READ_DELAY);
+ index = 0;
+ intel_de_rmw(display, DPST_CTL(intel_crtc->pipe),
+ DPST_CTL_BIN_REG_FUNC_SEL |
+ DPST_CTL_BIN_REG_MASK, 0);
+ }
+ }
+ return true;
+}
+
+static void intel_histogram_handle_int_work(struct work_struct *work)
+{
+ struct intel_histogram *histogram = container_of(work,
+ struct intel_histogram, work.work);
+ struct intel_crtc *intel_crtc = histogram->crtc;
+ struct intel_display *display = to_intel_display(intel_crtc);
+ char *histogram_event[] = {"HISTOGRAM=1", NULL};
+
+ /*
+ * TODO: PSR to be exited while reading the Histogram data
+ * Set DPST_CTL Bin Reg function select to TC
+ * Set DPST_CTL Bin Register Index to 0
+ */
+ intel_de_rmw(display, DPST_CTL(intel_crtc->pipe),
+ DPST_CTL_BIN_REG_FUNC_SEL | DPST_CTL_BIN_REG_MASK, 0);
+ if (intel_histogram_get_data(intel_crtc)) {
+ /* Notify user for Histogram rediness */
+ if (kobject_uevent_env(&display->drm->primary->kdev->kobj,
+ KOBJ_CHANGE, histogram_event))
+ drm_err(display->drm,
+ "sending HISTOGRAM event failed\n");
+ }
+
+ /* Enable histogram interrupt */
+ intel_de_rmw(display, DPST_GUARD(intel_crtc->pipe), DPST_GUARD_HIST_INT_EN,
+ DPST_GUARD_HIST_INT_EN);
+
+ /* Clear histogram interrupt by setting histogram interrupt status bit*/
+ intel_de_rmw(display, DPST_GUARD(intel_crtc->pipe),
+ DPST_GUARD_HIST_EVENT_STATUS, 1);
+}
+
+void intel_histogram_irq_handler(struct intel_display *display, enum pipe pipe)
+{
+ struct intel_crtc *intel_crtc =
+ to_intel_crtc(drm_crtc_from_index(display->drm, pipe));
+ struct intel_histogram *histogram = intel_crtc->histogram;
+ struct drm_i915_private *i915 = to_i915(intel_crtc->base.dev);
+
+ if (!histogram->enable) {
+ drm_err(display->drm,
+ "spurious interrupt, histogram not enabled\n");
+ return;
+ }
+
+ queue_delayed_work(i915->unordered_wq,
+ &histogram->work, 0);
+}
+
int intel_histogram_atomic_check(struct intel_crtc *intel_crtc)
{
struct intel_histogram *histogram = intel_crtc->histogram;
@@ -113,6 +201,7 @@ static void intel_histogram_disable(struct intel_crtc *intel_crtc)
intel_de_rmw(display, DPST_CTL(pipe),
DPST_CTL_IE_HIST_EN, 0);
+ cancel_delayed_work(&histogram->work);
histogram->enable = false;
}
@@ -174,6 +263,7 @@ void intel_histogram_finish(struct intel_crtc *intel_crtc)
{
struct intel_histogram *histogram = intel_crtc->histogram;
+ cancel_delayed_work_sync(&histogram->work);
kfree(histogram);
}
@@ -191,5 +281,8 @@ int intel_histogram_init(struct intel_crtc *intel_crtc)
histogram->crtc = intel_crtc;
histogram->can_enable = false;
+ INIT_DEFERRABLE_WORK(&histogram->work,
+ intel_histogram_handle_int_work);
+
return 0;
}
diff --git a/drivers/gpu/drm/i915/display/intel_histogram.h b/drivers/gpu/drm/i915/display/intel_histogram.h
index 9d66724f9c53..14f2425e3038 100644
--- a/drivers/gpu/drm/i915/display/intel_histogram.h
+++ b/drivers/gpu/drm/i915/display/intel_histogram.h
@@ -9,6 +9,8 @@
#include <linux/types.h>
struct intel_crtc;
+struct intel_display;
+enum pipe;
#define HISTOGRAM_BIN_COUNT 32
#define HISTOGRAM_IET_LENGTH 33
@@ -27,6 +29,7 @@ enum intel_global_hist_lut {
};
int intel_histogram_atomic_check(struct intel_crtc *intel_crtc);
+void intel_histogram_irq_handler(struct intel_display *display, enum pipe pipe);
int intel_histogram_update(struct intel_crtc *intel_crtc, bool enable);
int intel_histogram_set_iet_lut(struct intel_crtc *intel_crtc, u32 *data);
int intel_histogram_init(struct intel_crtc *intel_crtc);
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 7a35be56b7ef..40a7c6a77bcc 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -1605,7 +1605,7 @@
#define PIPE_HOTPLUG_INTERRUPT_ENABLE (1UL << 26)
#define PIPE_VSYNC_INTERRUPT_ENABLE (1UL << 25)
#define PIPE_DISPLAY_LINE_COMPARE_ENABLE (1UL << 24)
-#define PIPE_DPST_EVENT_ENABLE (1UL << 23)
+#define PIPE_HISTOGRAM_EVENT_ENABLE (1UL << 23)
#define SPRITE0_FLIP_DONE_INT_EN_VLV (1UL << 22)
#define PIPE_LEGACY_BLC_EVENT_ENABLE (1UL << 22)
#define PIPE_ODD_FIELD_INTERRUPT_ENABLE (1UL << 21)
@@ -1628,7 +1628,7 @@
#define PIPE_HOTPLUG_INTERRUPT_STATUS (1UL << 10)
#define PIPE_VSYNC_INTERRUPT_STATUS (1UL << 9)
#define PIPE_DISPLAY_LINE_COMPARE_STATUS (1UL << 8)
-#define PIPE_DPST_EVENT_STATUS (1UL << 7)
+#define PIPE_HISTOGRAM_EVENT_STATUS (1UL << 7)
#define PIPE_A_PSR_STATUS_VLV (1UL << 6)
#define PIPE_LEGACY_BLC_EVENT_STATUS (1UL << 6)
#define PIPE_ODD_FIELD_INTERRUPT_STATUS (1UL << 5)
@@ -2470,6 +2470,7 @@
#define GEN12_DSB_1_INT REG_BIT(14) /* tgl+ */
#define GEN12_DSB_0_INT REG_BIT(13) /* tgl+ */
#define GEN12_DSB_INT(dsb_id) REG_BIT(13 + (dsb_id))
+#define GEN9_PIPE_HISTOGRAM_EVENT REG_BIT(12) /* skl+ */
#define GEN9_PIPE_CURSOR_FAULT REG_BIT(11) /* skl+ */
#define GEN9_PIPE_PLANE4_FAULT REG_BIT(10) /* skl+ */
#define GEN8_PIPE_CURSOR_FAULT REG_BIT(10) /* bdw */
--
2.25.1
