From: Ville Syrjälä <[email protected]>
We use forcewake to prevent the SoC from actually entering
PC8 while performing the PC8 disable sequence. Hide that
behind a new parent interface to eliminate the naked
forcewake/uncore usage from the display power code.
v2: Mark the interface optional and warn if
someone calls it when not provided (Jani)
Include the header to make sure the extern
declaration matches the definition (Jani)
v3: Rebase due to shuffling
Reviewed-by: Jani Nikula <[email protected]>
Signed-off-by: Ville Syrjälä <[email protected]>
---
drivers/gpu/drm/i915/Makefile | 1 +
.../drm/i915/display/intel_display_power.c | 8 ++---
drivers/gpu/drm/i915/display/intel_parent.c | 17 ++++++++++
drivers/gpu/drm/i915/display/intel_parent.h | 4 +++
drivers/gpu/drm/i915/i915_display_pc8.c | 31 +++++++++++++++++++
drivers/gpu/drm/i915/i915_display_pc8.h | 9 ++++++
drivers/gpu/drm/i915/i915_driver.c | 2 ++
include/drm/intel/display_parent_interface.h | 8 +++++
8 files changed, 76 insertions(+), 4 deletions(-)
create mode 100644 drivers/gpu/drm/i915/i915_display_pc8.c
create mode 100644 drivers/gpu/drm/i915/i915_display_pc8.h
diff --git a/drivers/gpu/drm/i915/Makefile b/drivers/gpu/drm/i915/Makefile
index f01b5d8a07c7..5f7b2bbe448c 100644
--- a/drivers/gpu/drm/i915/Makefile
+++ b/drivers/gpu/drm/i915/Makefile
@@ -76,6 +76,7 @@ i915-$(CONFIG_PERF_EVENTS) += \
# core display adaptation
i915-y += \
+ i915_display_pc8.o \
i915_hdcp_gsc.o \
i915_panic.o
diff --git a/drivers/gpu/drm/i915/display/intel_display_power.c
b/drivers/gpu/drm/i915/display/intel_display_power.c
index 9f323c39d798..47042a4c3a30 100644
--- a/drivers/gpu/drm/i915/display/intel_display_power.c
+++ b/drivers/gpu/drm/i915/display/intel_display_power.c
@@ -1339,10 +1339,10 @@ static void hsw_restore_lcpll(struct intel_display
*display)
return;
/*
- * Make sure we're not on PC8 state before disabling PC8, otherwise
- * we'll hang the machine. To prevent PC8 state, just enable force_wake.
+ * Make sure we're not on PC8 state before disabling
+ * PC8, otherwise we'll hang the machine.
*/
- intel_uncore_forcewake_get(&dev_priv->uncore, FORCEWAKE_ALL);
+ intel_parent_pc8_block(display);
if (val & LCPLL_POWER_DOWN_ALLOW) {
val &= ~LCPLL_POWER_DOWN_ALLOW;
@@ -1372,7 +1372,7 @@ static void hsw_restore_lcpll(struct intel_display
*display)
"Switching back to LCPLL failed\n");
}
- intel_uncore_forcewake_put(&dev_priv->uncore, FORCEWAKE_ALL);
+ intel_parent_pc8_unblock(display);
intel_update_cdclk(display);
intel_cdclk_dump_config(display, &display->cdclk.hw, "Current CDCLK");
diff --git a/drivers/gpu/drm/i915/display/intel_parent.c
b/drivers/gpu/drm/i915/display/intel_parent.c
index 9b1a84a439e9..72ae553f79a4 100644
--- a/drivers/gpu/drm/i915/display/intel_parent.c
+++ b/drivers/gpu/drm/i915/display/intel_parent.c
@@ -75,6 +75,23 @@ void intel_parent_panic_finish(struct intel_display
*display, struct intel_panic
display->parent->panic->finish(panic);
}
+/* pc8 */
+void intel_parent_pc8_block(struct intel_display *display)
+{
+ if (drm_WARN_ON_ONCE(display->drm, !display->parent->pc8))
+ return;
+
+ display->parent->pc8->block(display->drm);
+}
+
+void intel_parent_pc8_unblock(struct intel_display *display)
+{
+ if (drm_WARN_ON_ONCE(display->drm, !display->parent->pc8))
+ return;
+
+ display->parent->pc8->unblock(display->drm);
+}
+
/* rps */
bool intel_parent_rps_available(struct intel_display *display)
{
diff --git a/drivers/gpu/drm/i915/display/intel_parent.h
b/drivers/gpu/drm/i915/display/intel_parent.h
index a2a631fba118..47cdc14f9aa2 100644
--- a/drivers/gpu/drm/i915/display/intel_parent.h
+++ b/drivers/gpu/drm/i915/display/intel_parent.h
@@ -32,6 +32,10 @@ struct intel_panic *intel_parent_panic_alloc(struct
intel_display *display);
int intel_parent_panic_setup(struct intel_display *display, struct intel_panic
*panic, struct drm_scanout_buffer *sb);
void intel_parent_panic_finish(struct intel_display *display, struct
intel_panic *panic);
+/* pc8 */
+void intel_parent_pc8_block(struct intel_display *display);
+void intel_parent_pc8_unblock(struct intel_display *display);
+
/* rps */
bool intel_parent_rps_available(struct intel_display *display);
void intel_parent_rps_boost_if_not_started(struct intel_display *display,
struct dma_fence *fence);
diff --git a/drivers/gpu/drm/i915/i915_display_pc8.c
b/drivers/gpu/drm/i915/i915_display_pc8.c
new file mode 100644
index 000000000000..2af5dbab20ef
--- /dev/null
+++ b/drivers/gpu/drm/i915/i915_display_pc8.c
@@ -0,0 +1,31 @@
+// SPDX-License-Identifier: MIT
+/*
+ * Copyright 2025, Intel Corporation.
+ */
+
+#include <drm/drm_print.h>
+#include <drm/intel/display_parent_interface.h>
+
+#include "i915_display_pc8.h"
+#include "i915_drv.h"
+#include "intel_uncore.h"
+
+static void i915_display_pc8_block(struct drm_device *drm)
+{
+ struct intel_uncore *uncore = &to_i915(drm)->uncore;
+
+ /* to prevent PC8 state, just enable force_wake */
+ intel_uncore_forcewake_get(uncore, FORCEWAKE_ALL);
+}
+
+static void i915_display_pc8_unblock(struct drm_device *drm)
+{
+ struct intel_uncore *uncore = &to_i915(drm)->uncore;
+
+ intel_uncore_forcewake_put(uncore, FORCEWAKE_ALL);
+}
+
+const struct intel_display_pc8_interface i915_display_pc8_interface = {
+ .block = i915_display_pc8_block,
+ .unblock = i915_display_pc8_unblock,
+};
diff --git a/drivers/gpu/drm/i915/i915_display_pc8.h
b/drivers/gpu/drm/i915/i915_display_pc8.h
new file mode 100644
index 000000000000..717f313d2a21
--- /dev/null
+++ b/drivers/gpu/drm/i915/i915_display_pc8.h
@@ -0,0 +1,9 @@
+/* SPDX-License-Identifier: MIT */
+/* Copyright © 2025 Intel Corporation */
+
+#ifndef __I915_DISPLAY_PC8_H__
+#define __I915_DISPLAY_PC8_H__
+
+extern const struct intel_display_pc8_interface i915_display_pc8_interface;
+
+#endif /* __I915_DISPLAY_PC8_H__ */
diff --git a/drivers/gpu/drm/i915/i915_driver.c
b/drivers/gpu/drm/i915/i915_driver.c
index 75f503e52e70..e025273e9ab1 100644
--- a/drivers/gpu/drm/i915/i915_driver.c
+++ b/drivers/gpu/drm/i915/i915_driver.c
@@ -89,6 +89,7 @@
#include "pxp/intel_pxp_pm.h"
#include "i915_debugfs.h"
+#include "i915_display_pc8.h"
#include "i915_driver.h"
#include "i915_drm_client.h"
#include "i915_drv.h"
@@ -765,6 +766,7 @@ static const struct intel_display_parent_interface parent =
{
.hdcp = &i915_display_hdcp_interface,
.irq = &i915_display_irq_interface,
.panic = &i915_display_panic_interface,
+ .pc8 = &i915_display_pc8_interface,
.rpm = &i915_display_rpm_interface,
.rps = &i915_display_rps_interface,
.stolen = &i915_display_stolen_interface,
diff --git a/include/drm/intel/display_parent_interface.h
b/include/drm/intel/display_parent_interface.h
index 55d4df714645..10c50b42844e 100644
--- a/include/drm/intel/display_parent_interface.h
+++ b/include/drm/intel/display_parent_interface.h
@@ -36,6 +36,11 @@ struct intel_display_panic_interface {
void (*finish)(struct intel_panic *panic);
};
+struct intel_display_pc8_interface {
+ void (*block)(struct drm_device *drm);
+ void (*unblock)(struct drm_device *drm);
+};
+
struct intel_display_rpm_interface {
struct ref_tracker *(*get)(const struct drm_device *drm);
struct ref_tracker *(*get_raw)(const struct drm_device *drm);
@@ -96,6 +101,9 @@ struct intel_display_parent_interface {
/** @panic: Panic interface */
const struct intel_display_panic_interface *panic;
+ /** @pc8: PC8 interface. Optional. */
+ const struct intel_display_pc8_interface *pc8;
+
/** @rpm: Runtime PM functions */
const struct intel_display_rpm_interface *rpm;
--
2.51.2
