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

Source file repositories/reference/linux-study-clean/drivers/gpu/drm/i915/pxp/intel_pxp_session.c

File Facts

System
Linux kernel
Corpus path
drivers/gpu/drm/i915/pxp/intel_pxp_session.c
Extension
.c
Size
4858 bytes
Lines
193
Domain
Driver Families
Bucket
drivers/gpu
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

// SPDX-License-Identifier: MIT
/*
 * Copyright(c) 2020, Intel Corporation. All rights reserved.
 */

#include <drm/drm_print.h>

#include "i915_drv.h"

#include "intel_pxp.h"
#include "intel_pxp_cmd.h"
#include "intel_pxp_gsccs.h"
#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 */

static bool intel_pxp_session_is_in_play(struct intel_pxp *pxp, u32 id)
{
	struct intel_uncore *uncore = pxp->ctrl_gt->uncore;
	intel_wakeref_t wakeref;
	u32 sip = 0;

	/* if we're suspended the session is considered off */
	with_intel_runtime_pm_if_in_use(uncore->rpm, wakeref)
		sip = intel_uncore_read(uncore, KCR_SIP(pxp->kcr_base));

	return sip & BIT(id);
}

static int pxp_wait_for_session_state(struct intel_pxp *pxp, u32 id, bool in_play)
{
	struct intel_uncore *uncore = pxp->ctrl_gt->uncore;
	intel_wakeref_t wakeref;
	u32 mask = BIT(id);
	int ret;

	/* if we're suspended the session is considered off */
	wakeref = intel_runtime_pm_get_if_in_use(uncore->rpm);
	if (!wakeref)
		return in_play ? -ENODEV : 0;

	ret = intel_wait_for_register(uncore,
				      KCR_SIP(pxp->kcr_base),
				      mask,
				      in_play ? mask : 0,
				      250);

	intel_runtime_pm_put(uncore->rpm, wakeref);

	return ret;
}

static int pxp_create_arb_session(struct intel_pxp *pxp)
{
	struct intel_gt *gt = pxp->ctrl_gt;
	int ret;

	pxp->arb_is_valid = false;

	if (intel_pxp_session_is_in_play(pxp, ARB_SESSION)) {
		drm_err(&gt->i915->drm, "arb session already in play at creation time\n");
		return -EEXIST;
	}

	if (HAS_ENGINE(pxp->ctrl_gt, GSC0))
		ret = intel_pxp_gsccs_create_session(pxp, ARB_SESSION);
	else
		ret = intel_pxp_tee_cmd_create_arb_session(pxp, ARB_SESSION);
	if (ret) {
		drm_err(&gt->i915->drm, "tee cmd for arb session creation failed\n");
		return ret;
	}

	ret = pxp_wait_for_session_state(pxp, ARB_SESSION, true);
	if (ret) {
		drm_dbg(&gt->i915->drm, "arb session failed to go in play\n");
		return ret;
	}
	drm_dbg(&gt->i915->drm, "PXP ARB session is alive\n");

	if (!++pxp->key_instance)
		++pxp->key_instance;

	pxp->arb_is_valid = true;

	return 0;
}

Annotation

Implementation Notes