1// SPDX-License-Identifier: MIT
2/*
3 * Copyright(c) 2020, Intel Corporation. All rights reserved.
4 */
5
6#include "i915_drv.h"
7
8#include "intel_pxp.h"
9#include "intel_pxp_cmd.h"
10#include "intel_pxp_gsccs.h"
11#include "intel_pxp_session.h"
12#include "intel_pxp_tee.h"
13#include "intel_pxp_types.h"
14#include "intel_pxp_regs.h"
15
16#define ARB_SESSION I915_PROTECTED_CONTENT_DEFAULT_SESSION /* shorter define */
17
18static bool intel_pxp_session_is_in_play(struct intel_pxp *pxp, u32 id)
19{
20 struct intel_uncore *uncore = pxp->ctrl_gt->uncore;
21 intel_wakeref_t wakeref;
22 u32 sip = 0;
23
24 /* if we're suspended the session is considered off */
25 with_intel_runtime_pm_if_in_use(uncore->rpm, wakeref)
26 sip = intel_uncore_read(uncore, KCR_SIP(pxp->kcr_base));
27
28 return sip & BIT(id);
29}
30
31static int pxp_wait_for_session_state(struct intel_pxp *pxp, u32 id, bool in_play)
32{
33 struct intel_uncore *uncore = pxp->ctrl_gt->uncore;
34 intel_wakeref_t wakeref;
35 u32 mask = BIT(id);
36 int ret;
37
38 /* if we're suspended the session is considered off */
39 wakeref = intel_runtime_pm_get_if_in_use(rpm: uncore->rpm);
40 if (!wakeref)
41 return in_play ? -ENODEV : 0;
42
43 ret = intel_wait_for_register(uncore,
44 KCR_SIP(pxp->kcr_base),
45 mask,
46 value: in_play ? mask : 0,
47 timeout_ms: 250);
48
49 intel_runtime_pm_put(rpm: uncore->rpm, wref: wakeref);
50
51 return ret;
52}
53
54static int pxp_create_arb_session(struct intel_pxp *pxp)
55{
56 struct intel_gt *gt = pxp->ctrl_gt;
57 int ret;
58
59 pxp->arb_is_valid = false;
60
61 if (intel_pxp_session_is_in_play(pxp, ARB_SESSION)) {
62 drm_err(&gt->i915->drm, "arb session already in play at creation time\n");
63 return -EEXIST;
64 }
65
66 if (HAS_ENGINE(pxp->ctrl_gt, GSC0))
67 ret = intel_pxp_gsccs_create_session(pxp, ARB_SESSION);
68 else
69 ret = intel_pxp_tee_cmd_create_arb_session(pxp, ARB_SESSION);
70 if (ret) {
71 drm_err(&gt->i915->drm, "tee cmd for arb session creation failed\n");
72 return ret;
73 }
74
75 ret = pxp_wait_for_session_state(pxp, ARB_SESSION, in_play: true);
76 if (ret) {
77 drm_dbg(&gt->i915->drm, "arb session failed to go in play\n");
78 return ret;
79 }
80 drm_dbg(&gt->i915->drm, "PXP ARB session is alive\n");
81
82 if (!++pxp->key_instance)
83 ++pxp->key_instance;
84
85 pxp->arb_is_valid = true;
86
87 return 0;
88}
89
90static int pxp_terminate_arb_session_and_global(struct intel_pxp *pxp)
91{
92 int ret;
93 struct intel_gt *gt = pxp->ctrl_gt;
94
95 /* must mark termination in progress calling this function */
96 GEM_WARN_ON(pxp->arb_is_valid);
97
98 /* terminate the hw sessions */
99 ret = intel_pxp_terminate_session(pxp, ARB_SESSION);
100 if (ret) {
101 drm_err(&gt->i915->drm, "Failed to submit session termination\n");
102 return ret;
103 }
104
105 ret = pxp_wait_for_session_state(pxp, ARB_SESSION, in_play: false);
106 if (ret) {
107 drm_err(&gt->i915->drm, "Session state did not clear\n");
108 return ret;
109 }
110
111 intel_uncore_write(uncore: gt->uncore, KCR_GLOBAL_TERMINATE(pxp->kcr_base), val: 1);
112
113 if (HAS_ENGINE(gt, GSC0))
114 intel_pxp_gsccs_end_arb_fw_session(pxp, ARB_SESSION);
115 else
116 intel_pxp_tee_end_arb_fw_session(pxp, ARB_SESSION);
117
118 return ret;
119}
120
121void intel_pxp_terminate(struct intel_pxp *pxp, bool post_invalidation_needs_restart)
122{
123 int ret;
124
125 pxp->hw_state_invalidated = post_invalidation_needs_restart;
126
127 /*
128 * if we fail to submit the termination there is no point in waiting for
129 * it to complete. PXP will be marked as non-active until the next
130 * termination is issued.
131 */
132 ret = pxp_terminate_arb_session_and_global(pxp);
133 if (ret)
134 complete_all(&pxp->termination);
135}
136
137static void pxp_terminate_complete(struct intel_pxp *pxp)
138{
139 /* Re-create the arb session after teardown handle complete */
140 if (fetch_and_zero(&pxp->hw_state_invalidated)) {
141 drm_dbg(&pxp->ctrl_gt->i915->drm, "PXP: creating arb_session after invalidation");
142 pxp_create_arb_session(pxp);
143 }
144
145 complete_all(&pxp->termination);
146}
147
148static void pxp_session_work(struct work_struct *work)
149{
150 struct intel_pxp *pxp = container_of(work, typeof(*pxp), session_work);
151 struct intel_gt *gt = pxp->ctrl_gt;
152 intel_wakeref_t wakeref;
153 u32 events = 0;
154
155 spin_lock_irq(lock: gt->irq_lock);
156 events = fetch_and_zero(&pxp->session_events);
157 spin_unlock_irq(lock: gt->irq_lock);
158
159 if (!events)
160 return;
161
162 drm_dbg(&gt->i915->drm, "PXP: processing event-flags 0x%08x", events);
163
164 if (events & PXP_INVAL_REQUIRED)
165 intel_pxp_invalidate(pxp);
166
167 /*
168 * If we're processing an event while suspending then don't bother,
169 * we're going to re-init everything on resume anyway.
170 */
171 wakeref = intel_runtime_pm_get_if_in_use(rpm: gt->uncore->rpm);
172 if (!wakeref)
173 return;
174
175 if (events & PXP_TERMINATION_REQUEST) {
176 events &= ~PXP_TERMINATION_COMPLETE;
177 intel_pxp_terminate(pxp, post_invalidation_needs_restart: true);
178 }
179
180 if (events & PXP_TERMINATION_COMPLETE)
181 pxp_terminate_complete(pxp);
182
183 intel_runtime_pm_put(rpm: gt->uncore->rpm, wref: wakeref);
184}
185
186void intel_pxp_session_management_init(struct intel_pxp *pxp)
187{
188 mutex_init(&pxp->arb_mutex);
189 INIT_WORK(&pxp->session_work, pxp_session_work);
190}
191

source code of linux/drivers/gpu/drm/i915/pxp/intel_pxp_session.c