[PATCH v7 1/2] drm/xe: Decouple GuC RC code from xe_guc_pc

[Vinay Belgaumkar <vinay.belgaumkar@intel.com>]

Move enable/disable GuC RC logic into the new file. This will
allow us to independently enable/disable GuC RC and not rely
on SLPC related functions. GuC already provides separate H2G
interfaces to setup GuC RC and SLPC.

Cc: Riana Tauro <riana.tauro@intel.com>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Signed-off-by: Vinay Belgaumkar <vinay.belgaumkar@intel.com>
---
v2: Comments (Michal W), remove duplicate c6_enable calls from
xe_guc_pc.

v3: Clarify crosss interactions between xe_guc_rc and xe_guc_pc
(Michal W)

v4: More comments (Michal W)

v5: Remove rc_init and use enable/disable (Riana)

v6: Link to kernel docs (Riana)

v7: Don't call devm_add_action_or_reset() in rc_enable (Michal W)
---
 Documentation/gpu/xe/xe_firmware.rst |   3 +
 drivers/gpu/drm/xe/Makefile          |   1 +
 drivers/gpu/drm/xe/xe_gt.c           |   1 -
 drivers/gpu/drm/xe/xe_guc.c          |   6 ++
 drivers/gpu/drm/xe/xe_guc_pc.c       |  70 +++------------
 drivers/gpu/drm/xe/xe_guc_pc.h       |   1 -
 drivers/gpu/drm/xe/xe_guc_rc.c       | 129 +++++++++++++++++++++++++++
 drivers/gpu/drm/xe/xe_guc_rc.h       |  15 ++++
 drivers/gpu/drm/xe/xe_uc.c           |  10 +--
 drivers/gpu/drm/xe/xe_uc.h           |   1 -
 10 files changed, 172 insertions(+), 65 deletions(-)
 create mode 100644 drivers/gpu/drm/xe/xe_guc_rc.c
 create mode 100644 drivers/gpu/drm/xe/xe_guc_rc.h

diff --git a/Documentation/gpu/xe/xe_firmware.rst b/Documentation/gpu/xe/xe_firmware.rst
index 5d23e9f27391..9c15a300bc62 100644
--- a/Documentation/gpu/xe/xe_firmware.rst
+++ b/Documentation/gpu/xe/xe_firmware.rst
@@ -31,6 +31,9 @@ GuC Power Conservation (PC)
 .. kernel-doc:: drivers/gpu/drm/xe/xe_guc_pc.c
    :doc: GuC Power Conservation (PC)
 
+.. kernel-doc:: drivers/gpu/drm/xe/xe_guc_rc.c
+   :doc: GuC Render C-states (GuC RC)
+
 PCIe Gen5 Limitations
 =====================
 
diff --git a/drivers/gpu/drm/xe/Makefile b/drivers/gpu/drm/xe/Makefile
index 51a9a531fb7e..41ec698b3cc1 100644
--- a/drivers/gpu/drm/xe/Makefile
+++ b/drivers/gpu/drm/xe/Makefile
@@ -74,6 +74,7 @@ xe-y += xe_bb.o \
 	xe_guc_log.o \
 	xe_guc_pagefault.o \
 	xe_guc_pc.o \
+	xe_guc_rc.o \
 	xe_guc_submit.o \
 	xe_guc_tlb_inval.o \
 	xe_heci_gsc.o \
diff --git a/drivers/gpu/drm/xe/xe_gt.c b/drivers/gpu/drm/xe/xe_gt.c
index 9d090d0f2438..c8a1d44bbf3a 100644
--- a/drivers/gpu/drm/xe/xe_gt.c
+++ b/drivers/gpu/drm/xe/xe_gt.c
@@ -852,7 +852,6 @@ static void gt_reset_worker(struct work_struct *w)
 	if (IS_SRIOV_PF(gt_to_xe(gt)))
 		xe_gt_sriov_pf_stop_prepare(gt);
 
-	xe_uc_gucrc_disable(&gt->uc);
 	xe_uc_stop_prepare(&gt->uc);
 	xe_pagefault_reset(gt_to_xe(gt), gt);
 
diff --git a/drivers/gpu/drm/xe/xe_guc.c b/drivers/gpu/drm/xe/xe_guc.c
index 2efc4678fa73..dc198d499da3 100644
--- a/drivers/gpu/drm/xe/xe_guc.c
+++ b/drivers/gpu/drm/xe/xe_guc.c
@@ -35,6 +35,7 @@
 #include "xe_guc_klv_helpers.h"
 #include "xe_guc_log.h"
 #include "xe_guc_pc.h"
+#include "xe_guc_rc.h"
 #include "xe_guc_relay.h"
 #include "xe_guc_submit.h"
 #include "xe_memirq.h"
@@ -880,6 +881,10 @@ int xe_guc_init_post_hwconfig(struct xe_guc *guc)
 	if (ret)
 		return ret;
 
+	ret = xe_guc_rc_init(guc);
+	if (ret)
+		return ret;
+
 	ret = xe_guc_engine_activity_init(guc);
 	if (ret)
 		return ret;
@@ -1620,6 +1625,7 @@ void xe_guc_stop_prepare(struct xe_guc *guc)
 	if (!IS_SRIOV_VF(guc_to_xe(guc))) {
 		int err;
 
+		xe_guc_rc_disable(guc);
 		err = xe_guc_pc_stop(&guc->pc);
 		xe_gt_WARN(guc_to_gt(guc), err, "Failed to stop GuC PC: %pe\n",
 			   ERR_PTR(err));
diff --git a/drivers/gpu/drm/xe/xe_guc_pc.c b/drivers/gpu/drm/xe/xe_guc_pc.c
index 5e5495a39a3c..878eb273c3e6 100644
--- a/drivers/gpu/drm/xe/xe_guc_pc.c
+++ b/drivers/gpu/drm/xe/xe_guc_pc.c
@@ -92,6 +92,17 @@
  * Render-C states is also a GuC PC feature that is now enabled in Xe for
  * all platforms.
  *
+ * Implementation details:
+ * -----------------------
+ * The implementation for GuC Power Management features is split as follows:
+ *
+ * xe_guc_rc:  Logic for handling GuC RC
+ * xe_gt_idle: Host side logic for RC6 and Coarse Power gating (CPG)
+ * xe_guc_pc:  Logic for all other SLPC related features
+ *
+ * There is some cross interaction between these where host C6 will need to be
+ * enabled when we plan to skip GuC RC. Also, the GuC RC mode is currently
+ * overridden through 0x3003 which is an SLPC H2G call.
  */
 
 static struct xe_guc *pc_to_guc(struct xe_guc_pc *pc)
@@ -253,22 +264,6 @@ static int pc_action_unset_param(struct xe_guc_pc *pc, u8 id)
 	return ret;
 }
 
-static int pc_action_setup_gucrc(struct xe_guc_pc *pc, u32 mode)
-{
-	struct xe_guc_ct *ct = pc_to_ct(pc);
-	u32 action[] = {
-		GUC_ACTION_HOST2GUC_SETUP_PC_GUCRC,
-		mode,
-	};
-	int ret;
-
-	ret = xe_guc_ct_send(ct, action, ARRAY_SIZE(action), 0, 0);
-	if (ret && !(xe_device_wedged(pc_to_xe(pc)) && ret == -ECANCELED))
-		xe_gt_err(pc_to_gt(pc), "GuC RC enable mode=%u failed: %pe\n",
-			  mode, ERR_PTR(ret));
-	return ret;
-}
-
 static u32 decode_freq(u32 raw)
 {
 	return DIV_ROUND_CLOSEST(raw * GT_FREQUENCY_MULTIPLIER,
@@ -1050,30 +1045,6 @@ int xe_guc_pc_restore_stashed_freq(struct xe_guc_pc *pc)
 	return ret;
 }
 
-/**
- * xe_guc_pc_gucrc_disable - Disable GuC RC
- * @pc: Xe_GuC_PC instance
- *
- * Disables GuC RC by taking control of RC6 back from GuC.
- *
- * Return: 0 on success, negative error code on error.
- */
-int xe_guc_pc_gucrc_disable(struct xe_guc_pc *pc)
-{
-	struct xe_device *xe = pc_to_xe(pc);
-	struct xe_gt *gt = pc_to_gt(pc);
-	int ret = 0;
-
-	if (xe->info.skip_guc_pc)
-		return 0;
-
-	ret = pc_action_setup_gucrc(pc, GUCRC_HOST_CONTROL);
-	if (ret)
-		return ret;
-
-	return xe_gt_idle_disable_c6(gt);
-}
-
 /**
  * xe_guc_pc_override_gucrc_mode - override GUCRC mode
  * @pc: Xe_GuC_PC instance
@@ -1247,9 +1218,6 @@ int xe_guc_pc_start(struct xe_guc_pc *pc)
 		return -ETIMEDOUT;
 
 	if (xe->info.skip_guc_pc) {
-		if (xe->info.platform != XE_PVC)
-			xe_gt_idle_enable_c6(gt);
-
 		/* Request max possible since dynamic freq mgmt is not enabled */
 		pc_set_cur_freq(pc, UINT_MAX);
 		return 0;
@@ -1291,15 +1259,6 @@ int xe_guc_pc_start(struct xe_guc_pc *pc)
 	if (ret)
 		return ret;
 
-	if (xe->info.platform == XE_PVC) {
-		xe_guc_pc_gucrc_disable(pc);
-		return 0;
-	}
-
-	ret = pc_action_setup_gucrc(pc, GUCRC_FIRMWARE_CONTROL);
-	if (ret)
-		return ret;
-
 	/* Enable SLPC Optimized Strategy for compute */
 	ret = pc_action_set_strategy(pc, SLPC_OPTIMIZED_STRATEGY_COMPUTE);
 
@@ -1319,10 +1278,8 @@ int xe_guc_pc_stop(struct xe_guc_pc *pc)
 {
 	struct xe_device *xe = pc_to_xe(pc);
 
-	if (xe->info.skip_guc_pc) {
-		xe_gt_idle_disable_c6(pc_to_gt(pc));
+	if (xe->info.skip_guc_pc)
 		return 0;
-	}
 
 	mutex_lock(&pc->freq_lock);
 	pc->freq_ready = false;
@@ -1343,8 +1300,7 @@ static void xe_guc_pc_fini_hw(void *arg)
 	if (xe_device_wedged(xe))
 		return;
 
-	CLASS(xe_force_wake, fw_ref)(gt_to_fw(pc_to_gt(pc)), XE_FORCEWAKE_ALL);
-	xe_guc_pc_gucrc_disable(pc);
+	CLASS(xe_force_wake, fw_ref)(gt_to_fw(pc_to_gt(pc)), XE_FW_GT);
 	XE_WARN_ON(xe_guc_pc_stop(pc));
 
 	/* Bind requested freq to mert_freq_cap before unload */
diff --git a/drivers/gpu/drm/xe/xe_guc_pc.h b/drivers/gpu/drm/xe/xe_guc_pc.h
index 0e31396f103c..1b95873b262e 100644
--- a/drivers/gpu/drm/xe/xe_guc_pc.h
+++ b/drivers/gpu/drm/xe/xe_guc_pc.h
@@ -15,7 +15,6 @@ struct drm_printer;
 int xe_guc_pc_init(struct xe_guc_pc *pc);
 int xe_guc_pc_start(struct xe_guc_pc *pc);
 int xe_guc_pc_stop(struct xe_guc_pc *pc);
-int xe_guc_pc_gucrc_disable(struct xe_guc_pc *pc);
 int xe_guc_pc_override_gucrc_mode(struct xe_guc_pc *pc, enum slpc_gucrc_mode mode);
 int xe_guc_pc_unset_gucrc_mode(struct xe_guc_pc *pc);
 void xe_guc_pc_print(struct xe_guc_pc *pc, struct drm_printer *p);
diff --git a/drivers/gpu/drm/xe/xe_guc_rc.c b/drivers/gpu/drm/xe/xe_guc_rc.c
new file mode 100644
index 000000000000..55eeee7b1011
--- /dev/null
+++ b/drivers/gpu/drm/xe/xe_guc_rc.c
@@ -0,0 +1,129 @@
+// SPDX-License-Identifier: MIT
+/*
+ * Copyright © 2026 Intel Corporation
+ */
+
+#include <drm/drm_print.h>
+
+#include "abi/guc_actions_slpc_abi.h"
+#include "xe_device.h"
+#include "xe_force_wake.h"
+#include "xe_gt.h"
+#include "xe_gt_idle.h"
+#include "xe_gt_printk.h"
+#include "xe_guc.h"
+#include "xe_guc_ct.h"
+#include "xe_guc_rc.h"
+#include "xe_pm.h"
+
+/**
+ * DOC: GuC RC (Render C-states)
+ *
+ * GuC handles the GT transition to deeper C-states in conjunction with Pcode.
+ * GuC RC can be enabled independently of the frequency component in SLPC,
+ * which is also controlled by GuC.
+ *
+ * This file will contain all H2G related logic for handling Render C-states.
+ * There are some calls to xe_gt_idle, where we enable host C6 when GuC RC is
+ * skipped. GuC RC is mostly independent of xe_guc_pc with the exception of
+ * functions that override the mode for which we have to rely on the SLPC H2G
+ * calls.
+ */
+
+static int guc_action_setup_gucrc(struct xe_guc *guc, u32 control)
+{
+	u32 action[] = {
+		GUC_ACTION_HOST2GUC_SETUP_PC_GUCRC,
+		control,
+	};
+	int ret;
+
+	ret = xe_guc_ct_send(&guc->ct, action, ARRAY_SIZE(action), 0, 0);
+	if (ret && !(xe_device_wedged(guc_to_xe(guc)) && ret == -ECANCELED))
+		xe_gt_err(guc_to_gt(guc),
+			  "GuC RC setup %s(%u) failed (%pe)\n",
+			   control == GUCRC_HOST_CONTROL ? "HOST_CONTROL" :
+			   control == GUCRC_FIRMWARE_CONTROL ? "FIRMWARE_CONTROL" :
+			   "UNKNOWN", control, ERR_PTR(ret));
+	return ret;
+}
+
+/**
+ * xe_guc_rc_disable() - Disable GuC RC
+ * @guc: Xe GuC instance
+ *
+ * Disables GuC RC by taking control of RC6 back from GuC.
+ */
+void xe_guc_rc_disable(struct xe_guc *guc)
+{
+	struct xe_device *xe = guc_to_xe(guc);
+
+	if (!xe->info.skip_guc_pc && xe->info.platform != XE_PVC)
+		if (guc_action_setup_gucrc(guc, GUCRC_HOST_CONTROL))
+			return;
+
+	xe_gt_WARN_ON(guc_to_gt(guc), xe_gt_idle_disable_c6(guc_to_gt(guc)));
+}
+
+static void xe_guc_rc_fini_hw(void *arg)
+{
+	struct xe_guc *guc = arg;
+	struct xe_device *xe = guc_to_xe(guc);
+	struct xe_gt *gt = guc_to_gt(guc);
+
+	if (xe_device_wedged(xe))
+		return;
+
+	CLASS(xe_force_wake, fw_ref)(gt_to_fw(gt), XE_FW_GT);
+	xe_guc_rc_disable(guc);
+}
+
+/**
+ * xe_guc_rc_init() - Init GuC RC
+ * @guc: Xe GuC instance
+ *
+ * Add callback action for GuC RC
+ *
+ * Return: 0 on success, negative error code on error.
+ */
+int xe_guc_rc_init(struct xe_guc *guc)
+{
+	struct xe_device *xe = guc_to_xe(guc);
+	struct xe_gt *gt = guc_to_gt(guc);
+
+	xe_gt_assert(gt, xe_device_uc_enabled(xe));
+
+	return devm_add_action_or_reset(xe->drm.dev, xe_guc_rc_fini_hw, guc);
+}
+
+/**
+ * xe_guc_rc_enable() - Enable GuC RC feature if applicable
+ * @guc: Xe GuC instance
+ *
+ * Enables GuC RC feature.
+ *
+ * Return: 0 on success, negative error code on error.
+ */
+int xe_guc_rc_enable(struct xe_guc *guc)
+{
+	struct xe_device *xe = guc_to_xe(guc);
+	struct xe_gt *gt = guc_to_gt(guc);
+
+	xe_gt_assert(gt, xe_device_uc_enabled(xe));
+
+	CLASS(xe_force_wake, fw_ref)(gt_to_fw(gt), XE_FW_GT);
+	if (!xe_force_wake_ref_has_domain(fw_ref.domains, XE_FW_GT))
+		return -ETIMEDOUT;
+
+	if (xe->info.platform == XE_PVC) {
+		xe_guc_rc_disable(guc);
+		return 0;
+	}
+
+	if (xe->info.skip_guc_pc) {
+		xe_gt_idle_enable_c6(gt);
+		return 0;
+	}
+
+	return guc_action_setup_gucrc(guc, GUCRC_FIRMWARE_CONTROL);
+}
diff --git a/drivers/gpu/drm/xe/xe_guc_rc.h b/drivers/gpu/drm/xe/xe_guc_rc.h
new file mode 100644
index 000000000000..35fabb82cb0e
--- /dev/null
+++ b/drivers/gpu/drm/xe/xe_guc_rc.h
@@ -0,0 +1,15 @@
+/* SPDX-License-Identifier: MIT */
+/*
+ * Copyright © 2026 Intel Corporation
+ */
+
+#ifndef _XE_GUC_RC_H_
+#define _XE_GUC_RC_H_
+
+struct xe_guc;
+
+int xe_guc_rc_init(struct xe_guc *guc);
+void xe_guc_rc_disable(struct xe_guc *guc);
+int xe_guc_rc_enable(struct xe_guc *guc);
+
+#endif
diff --git a/drivers/gpu/drm/xe/xe_uc.c b/drivers/gpu/drm/xe/xe_uc.c
index 3f63c2a7e86d..d9aa845a308d 100644
--- a/drivers/gpu/drm/xe/xe_uc.c
+++ b/drivers/gpu/drm/xe/xe_uc.c
@@ -13,6 +13,7 @@
 #include "xe_gt_sriov_vf.h"
 #include "xe_guc.h"
 #include "xe_guc_pc.h"
+#include "xe_guc_rc.h"
 #include "xe_guc_engine_activity.h"
 #include "xe_huc.h"
 #include "xe_sriov.h"
@@ -214,6 +215,10 @@ int xe_uc_load_hw(struct xe_uc *uc)
 	if (ret)
 		goto err_out;
 
+	ret = xe_guc_rc_enable(&uc->guc);
+	if (ret)
+		goto err_out;
+
 	xe_guc_engine_activity_enable_stats(&uc->guc);
 
 	/* We don't fail the driver load if HuC fails to auth */
@@ -242,11 +247,6 @@ int xe_uc_reset_prepare(struct xe_uc *uc)
 	return xe_guc_reset_prepare(&uc->guc);
 }
 
-void xe_uc_gucrc_disable(struct xe_uc *uc)
-{
-	XE_WARN_ON(xe_guc_pc_gucrc_disable(&uc->guc.pc));
-}
-
 void xe_uc_stop_prepare(struct xe_uc *uc)
 {
 	xe_gsc_stop_prepare(&uc->gsc);
diff --git a/drivers/gpu/drm/xe/xe_uc.h b/drivers/gpu/drm/xe/xe_uc.h
index 5398da1a8097..255a54a8f876 100644
--- a/drivers/gpu/drm/xe/xe_uc.h
+++ b/drivers/gpu/drm/xe/xe_uc.h
@@ -12,7 +12,6 @@ int xe_uc_init_noalloc(struct xe_uc *uc);
 int xe_uc_init(struct xe_uc *uc);
 int xe_uc_init_post_hwconfig(struct xe_uc *uc);
 int xe_uc_load_hw(struct xe_uc *uc);
-void xe_uc_gucrc_disable(struct xe_uc *uc);
 int xe_uc_reset_prepare(struct xe_uc *uc);
 void xe_uc_runtime_resume(struct xe_uc *uc);
 void xe_uc_runtime_suspend(struct xe_uc *uc);
-- 
2.38.1