drm/i915/pxp: Add MTL hw-plumbing enabling for KCR operation

Add MTL hw-plumbing enabling for KCR operation under PXP
which includes:

1. Updating 'pick-gt' to get the media tile for
   KCR interrupt handling
2. Adding MTL's KCR registers for PXP operation
   (init, status-checking, etc.).

While doing #2, lets create a separate registers header file for PXP
to be consistent with other i915 global subsystems.
Signed-off-by: Alan Previn <alan.previn.teres.alexis@intel.com>
Reviewed-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: Radhakrishna Sripada <radhakrishna.sripada@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230511231738.1077674-3-alan.previn.teres.alexis@intel.com

drivers/gpu/drm/i915/gt/intel_gt_irq.c

@@ -106,7 +106,8 @@ static struct intel_gt *pick_gt(struct intel_gt *gt, u8 class, u8 instance)
 	case OTHER_CLASS:
 		if (instance == OTHER_GSC_HECI_2_INSTANCE)
 			return media_gt;
-		if (instance == OTHER_GSC_INSTANCE && HAS_ENGINE(media_gt, GSC0))
+		if ((instance == OTHER_GSC_INSTANCE || instance == OTHER_KCR_INSTANCE) &&
+		    HAS_ENGINE(media_gt, GSC0))
 			return media_gt;
 		fallthrough;
 	default:

drivers/gpu/drm/i915/pxp/intel_pxp.c

@@ -14,6 +14,7 @@
 #include "intel_pxp.h"
 #include "intel_pxp_gsccs.h"
 #include "intel_pxp_irq.h"
+#include "intel_pxp_regs.h"
 #include "intel_pxp_session.h"
 #include "intel_pxp_tee.h"
 #include "intel_pxp_types.h"
@@ -61,21 +62,22 @@ bool intel_pxp_is_active(const struct intel_pxp *pxp)
 	return IS_ENABLED(CONFIG_DRM_I915_PXP) && pxp && pxp->arb_is_valid;
 }
 
-/* KCR register definitions */
-#define KCR_INIT _MMIO(0x320f0)
-/* Setting KCR Init bit is required after system boot */
-#define KCR_INIT_ALLOW_DISPLAY_ME_WRITES REG_BIT(14)
+static void kcr_pxp_set_status(const struct intel_pxp *pxp, bool enable)
+{
+	u32 val = enable ? _MASKED_BIT_ENABLE(KCR_INIT_ALLOW_DISPLAY_ME_WRITES) :
+		  _MASKED_BIT_DISABLE(KCR_INIT_ALLOW_DISPLAY_ME_WRITES);
+
+	intel_uncore_write(pxp->ctrl_gt->uncore, KCR_INIT(pxp->kcr_base), val);
+}
 
-static void kcr_pxp_enable(struct intel_gt *gt)
+static void kcr_pxp_enable(const struct intel_pxp *pxp)
 {
-	intel_uncore_write(gt->uncore, KCR_INIT,
-			   _MASKED_BIT_ENABLE(KCR_INIT_ALLOW_DISPLAY_ME_WRITES));
+	kcr_pxp_set_status(pxp, true);
 }
 
-static void kcr_pxp_disable(struct intel_gt *gt)
+static void kcr_pxp_disable(const struct intel_pxp *pxp)
 {
-	intel_uncore_write(gt->uncore, KCR_INIT,
-			   _MASKED_BIT_DISABLE(KCR_INIT_ALLOW_DISPLAY_ME_WRITES));
+	kcr_pxp_set_status(pxp, false);
 }
 
 static int create_vcs_context(struct intel_pxp *pxp)
@@ -127,6 +129,11 @@ static void pxp_init_full(struct intel_pxp *pxp)
 	init_completion(&pxp->termination);
 	complete_all(&pxp->termination);
 
+	if (pxp->ctrl_gt->type == GT_MEDIA)
+		pxp->kcr_base = MTL_KCR_BASE;
+	else
+		pxp->kcr_base = GEN12_KCR_BASE;
+
 	intel_pxp_session_management_init(pxp);
 
 	ret = create_vcs_context(pxp);
@@ -369,14 +376,13 @@ int intel_pxp_start(struct intel_pxp *pxp)
 
 void intel_pxp_init_hw(struct intel_pxp *pxp)
 {
-	kcr_pxp_enable(pxp->ctrl_gt);
+	kcr_pxp_enable(pxp);
 	intel_pxp_irq_enable(pxp);
 }
 
 void intel_pxp_fini_hw(struct intel_pxp *pxp)
 {
-	kcr_pxp_disable(pxp->ctrl_gt);
-
+	kcr_pxp_disable(pxp);
 	intel_pxp_irq_disable(pxp);
 }
 

drivers/gpu/drm/i915/pxp/intel_pxp_regs.h

+/* SPDX-License-Identifier: MIT */
+/*
+ * Copyright(c) 2023, Intel Corporation. All rights reserved.
+ */
+
+#ifndef __INTEL_PXP_REGS_H__
+#define __INTEL_PXP_REGS_H__
+
+#include "i915_reg_defs.h"
+
+/* KCR subsystem register base address */
+#define GEN12_KCR_BASE 0x32000
+#define MTL_KCR_BASE 0x386000
+
+/* KCR enable/disable control */
+#define KCR_INIT(base) _MMIO((base) + 0xf0)
+
+/* Setting KCR Init bit is required after system boot */
+#define KCR_INIT_ALLOW_DISPLAY_ME_WRITES REG_BIT(14)
+
+/* KCR hwdrm session in play status 0-31 */
+#define KCR_SIP(base) _MMIO((base) + 0x260)
+
+/* PXP global terminate register for session termination */
+#define KCR_GLOBAL_TERMINATE(base) _MMIO((base) + 0xf8)
+
+#endif /* __INTEL_PXP_REGS_H__ */

drivers/gpu/drm/i915/pxp/intel_pxp_session.c

@@ -10,14 +10,10 @@
 #include "intel_pxp_session.h"
 #include "intel_pxp_tee.h"
 #include "intel_pxp_types.h"
+#include "intel_pxp_regs.h"
 
 #define ARB_SESSION I915_PROTECTED_CONTENT_DEFAULT_SESSION /* shorter define */
 
-#define GEN12_KCR_SIP _MMIO(0x32260) /* KCR hwdrm session in play 0-31 */
-
-/* PXP global terminate register for session termination */
-#define PXP_GLOBAL_TERMINATE _MMIO(0x320f8)
-
 static bool intel_pxp_session_is_in_play(struct intel_pxp *pxp, u32 id)
 {
 	struct intel_uncore *uncore = pxp->ctrl_gt->uncore;
@@ -26,7 +22,7 @@ static bool intel_pxp_session_is_in_play(struct intel_pxp *pxp, u32 id)
 
 	/* if we're suspended the session is considered off */
 	with_intel_runtime_pm_if_in_use(uncore->rpm, wakeref)
-		sip = intel_uncore_read(uncore, GEN12_KCR_SIP);
+		sip = intel_uncore_read(uncore, KCR_SIP(pxp->kcr_base));
 
 	return sip & BIT(id);
 }
@@ -44,7 +40,7 @@ static int pxp_wait_for_session_state(struct intel_pxp *pxp, u32 id, bool in_pla
 		return in_play ? -ENODEV : 0;
 
 	ret = intel_wait_for_register(uncore,
-				      GEN12_KCR_SIP,
+				      KCR_SIP(pxp->kcr_base),
 				      mask,
 				      in_play ? mask : 0,
 				      100);
@@ -108,7 +104,7 @@ static int pxp_terminate_arb_session_and_global(struct intel_pxp *pxp)
 		return ret;
 	}
 
-	intel_uncore_write(gt->uncore, PXP_GLOBAL_TERMINATE, 1);
+	intel_uncore_write(gt->uncore, KCR_GLOBAL_TERMINATE(pxp->kcr_base), 1);
 
 	intel_pxp_tee_end_arb_fw_session(pxp, ARB_SESSION);
 

drivers/gpu/drm/i915/pxp/intel_pxp_types.h

@@ -26,6 +26,12 @@ struct intel_pxp {
 	 */
 	struct intel_gt *ctrl_gt;
 
+	/**
+	 * @kcr_base: base mmio offset for the KCR engine which is different on legacy platforms
+	 * vs newer platforms where the KCR is inside the media-tile.
+	 */
+	u32 kcr_base;
+
 	/**
 	 * @gsccs_res: resources for request submission for platforms that have a GSC engine.
 	 */