1// SPDX-License-Identifier: MIT
2/*
3 * Copyright �� 2013-2021 Intel Corporation
4 */
5
6#include "i915_drv.h"
7#include "i915_reg.h"
8#include "intel_pcode.h"
9
10static int gen6_check_mailbox_status(u32 mbox)
11{
12	switch (mbox & GEN6_PCODE_ERROR_MASK) {
13	case GEN6_PCODE_SUCCESS:
14		return 0;
15	case GEN6_PCODE_UNIMPLEMENTED_CMD:
16		return -ENODEV;
17	case GEN6_PCODE_ILLEGAL_CMD:
18		return -ENXIO;
19	case GEN6_PCODE_MIN_FREQ_TABLE_GT_RATIO_OUT_OF_RANGE:
20	case GEN7_PCODE_MIN_FREQ_TABLE_GT_RATIO_OUT_OF_RANGE:
21		return -EOVERFLOW;
22	case GEN6_PCODE_TIMEOUT:
23		return -ETIMEDOUT;
24	default:
25		MISSING_CASE(mbox & GEN6_PCODE_ERROR_MASK);
26		return 0;
27	}
28}
29
30static int gen7_check_mailbox_status(u32 mbox)
31{
32	switch (mbox & GEN6_PCODE_ERROR_MASK) {
33	case GEN6_PCODE_SUCCESS:
34		return 0;
35	case GEN6_PCODE_ILLEGAL_CMD:
36		return -ENXIO;
37	case GEN7_PCODE_TIMEOUT:
38		return -ETIMEDOUT;
39	case GEN7_PCODE_ILLEGAL_DATA:
40		return -EINVAL;
41	case GEN11_PCODE_ILLEGAL_SUBCOMMAND:
42		return -ENXIO;
43	case GEN11_PCODE_LOCKED:
44		return -EBUSY;
45	case GEN11_PCODE_REJECTED:
46		return -EACCES;
47	case GEN7_PCODE_MIN_FREQ_TABLE_GT_RATIO_OUT_OF_RANGE:
48		return -EOVERFLOW;
49	default:
50		MISSING_CASE(mbox & GEN6_PCODE_ERROR_MASK);
51		return 0;
52	}
53}
54
55static int __snb_pcode_rw(struct intel_uncore *uncore, u32 mbox,
56			  u32 *val, u32 *val1,
57			  int fast_timeout_us, int slow_timeout_ms,
58			  bool is_read)
59{
60	lockdep_assert_held(&uncore->i915->sb_lock);
61
62	/*
63	 * GEN6_PCODE_* are outside of the forcewake domain, we can use
64	 * intel_uncore_read/write_fw variants to reduce the amount of work
65	 * required when reading/writing.
66	 */
67
68	if (intel_uncore_read_fw(uncore, GEN6_PCODE_MAILBOX) & GEN6_PCODE_READY)
69		return -EAGAIN;
70
71	intel_uncore_write_fw(uncore, GEN6_PCODE_DATA, *val);
72	intel_uncore_write_fw(uncore, GEN6_PCODE_DATA1, val1 ? *val1 : 0);
73	intel_uncore_write_fw(uncore,
74			      GEN6_PCODE_MAILBOX, GEN6_PCODE_READY | mbox);
75
76	if (__intel_wait_for_register_fw(uncore,
77					 GEN6_PCODE_MAILBOX,
78					 GEN6_PCODE_READY, 0,
79					 fast_timeout_us,
80					 slow_timeout_ms,
81					 &mbox))
82		return -ETIMEDOUT;
83
84	if (is_read)
85		*val = intel_uncore_read_fw(uncore, GEN6_PCODE_DATA);
86	if (is_read && val1)
87		*val1 = intel_uncore_read_fw(uncore, GEN6_PCODE_DATA1);
88
89	if (GRAPHICS_VER(uncore->i915) > 6)
90		return gen7_check_mailbox_status(mbox);
91	else
92		return gen6_check_mailbox_status(mbox);
93}
94
95int snb_pcode_read(struct intel_uncore *uncore, u32 mbox, u32 *val, u32 *val1)
96{
97	int err;
98
99	mutex_lock(&uncore->i915->sb_lock);
100	err = __snb_pcode_rw(uncore, mbox, val, val1, 500, 20, true);
101	mutex_unlock(&uncore->i915->sb_lock);
102
103	if (err) {
104		drm_dbg(&uncore->i915->drm,
105			"warning: pcode (read from mbox %x) mailbox access failed for %ps: %d\n",
106			mbox, __builtin_return_address(0), err);
107	}
108
109	return err;
110}
111
112int snb_pcode_write_timeout(struct intel_uncore *uncore, u32 mbox, u32 val,
113			    int fast_timeout_us, int slow_timeout_ms)
114{
115	int err;
116
117	mutex_lock(&uncore->i915->sb_lock);
118	err = __snb_pcode_rw(uncore, mbox, &val, NULL,
119			     fast_timeout_us, slow_timeout_ms, false);
120	mutex_unlock(&uncore->i915->sb_lock);
121
122	if (err) {
123		drm_dbg(&uncore->i915->drm,
124			"warning: pcode (write of 0x%08x to mbox %x) mailbox access failed for %ps: %d\n",
125			val, mbox, __builtin_return_address(0), err);
126	}
127
128	return err;
129}
130
131static bool skl_pcode_try_request(struct intel_uncore *uncore, u32 mbox,
132				  u32 request, u32 reply_mask, u32 reply,
133				  u32 *status)
134{
135	*status = __snb_pcode_rw(uncore, mbox, &request, NULL, 500, 0, true);
136
137	return (*status == 0) && ((request & reply_mask) == reply);
138}
139
140/**
141 * skl_pcode_request - send PCODE request until acknowledgment
142 * @uncore: uncore
143 * @mbox: PCODE mailbox ID the request is targeted for
144 * @request: request ID
145 * @reply_mask: mask used to check for request acknowledgment
146 * @reply: value used to check for request acknowledgment
147 * @timeout_base_ms: timeout for polling with preemption enabled
148 *
149 * Keep resending the @request to @mbox until PCODE acknowledges it, PCODE
150 * reports an error or an overall timeout of @timeout_base_ms+50 ms expires.
151 * The request is acknowledged once the PCODE reply dword equals @reply after
152 * applying @reply_mask. Polling is first attempted with preemption enabled
153 * for @timeout_base_ms and if this times out for another 50 ms with
154 * preemption disabled.
155 *
156 * Returns 0 on success, %-ETIMEDOUT in case of a timeout, <0 in case of some
157 * other error as reported by PCODE.
158 */
159int skl_pcode_request(struct intel_uncore *uncore, u32 mbox, u32 request,
160		      u32 reply_mask, u32 reply, int timeout_base_ms)
161{
162	u32 status;
163	int ret;
164
165	mutex_lock(&uncore->i915->sb_lock);
166
167#define COND \
168	skl_pcode_try_request(uncore, mbox, request, reply_mask, reply, &status)
169
170	/*
171	 * Prime the PCODE by doing a request first. Normally it guarantees
172	 * that a subsequent request, at most @timeout_base_ms later, succeeds.
173	 * _wait_for() doesn't guarantee when its passed condition is evaluated
174	 * first, so send the first request explicitly.
175	 */
176	if (COND) {
177		ret = 0;
178		goto out;
179	}
180	ret = _wait_for(COND, timeout_base_ms * 1000, 10, 10);
181	if (!ret)
182		goto out;
183
184	/*
185	 * The above can time out if the number of requests was low (2 in the
186	 * worst case) _and_ PCODE was busy for some reason even after a
187	 * (queued) request and @timeout_base_ms delay. As a workaround retry
188	 * the poll with preemption disabled to maximize the number of
189	 * requests. Increase the timeout from @timeout_base_ms to 50ms to
190	 * account for interrupts that could reduce the number of these
191	 * requests, and for any quirks of the PCODE firmware that delays
192	 * the request completion.
193	 */
194	drm_dbg_kms(&uncore->i915->drm,
195		    "PCODE timeout, retrying with preemption disabled\n");
196	drm_WARN_ON_ONCE(&uncore->i915->drm, timeout_base_ms > 3);
197	preempt_disable();
198	ret = wait_for_atomic(COND, 50);
199	preempt_enable();
200
201out:
202	mutex_unlock(&uncore->i915->sb_lock);
203	return status ? status : ret;
204#undef COND
205}
206
207static int pcode_init_wait(struct intel_uncore *uncore, int timeout_ms)
208{
209	if (__intel_wait_for_register_fw(uncore,
210					 GEN6_PCODE_MAILBOX,
211					 GEN6_PCODE_READY, 0,
212					 500, timeout_ms,
213					 NULL))
214		return -EPROBE_DEFER;
215
216	return skl_pcode_request(uncore,
217				 DG1_PCODE_STATUS,
218				 DG1_UNCORE_GET_INIT_STATUS,
219				 DG1_UNCORE_INIT_STATUS_COMPLETE,
220				 DG1_UNCORE_INIT_STATUS_COMPLETE, timeout_ms);
221}
222
223int intel_pcode_init(struct intel_uncore *uncore)
224{
225	int err;
226
227	if (!IS_DGFX(uncore->i915))
228		return 0;
229
230	/*
231	 * Wait 10 seconds so that the punit to settle and complete
232	 * any outstanding transactions upon module load
233	 */
234	err = pcode_init_wait(uncore, 10000);
235
236	if (err) {
237		drm_notice(&uncore->i915->drm,
238			   "Waiting for HW initialisation...\n");
239		err = pcode_init_wait(uncore, 180000);
240	}
241
242	return err;
243}
244
245int snb_pcode_read_p(struct intel_uncore *uncore, u32 mbcmd, u32 p1, u32 p2, u32 *val)
246{
247	intel_wakeref_t wakeref;
248	u32 mbox;
249	int err;
250
251	mbox = REG_FIELD_PREP(GEN6_PCODE_MB_COMMAND, mbcmd)
252		| REG_FIELD_PREP(GEN6_PCODE_MB_PARAM1, p1)
253		| REG_FIELD_PREP(GEN6_PCODE_MB_PARAM2, p2);
254
255	with_intel_runtime_pm(uncore->rpm, wakeref)
256		err = snb_pcode_read(uncore, mbox, val, NULL);
257
258	return err;
259}
260
261int snb_pcode_write_p(struct intel_uncore *uncore, u32 mbcmd, u32 p1, u32 p2, u32 val)
262{
263	intel_wakeref_t wakeref;
264	u32 mbox;
265	int err;
266
267	mbox = REG_FIELD_PREP(GEN6_PCODE_MB_COMMAND, mbcmd)
268		| REG_FIELD_PREP(GEN6_PCODE_MB_PARAM1, p1)
269		| REG_FIELD_PREP(GEN6_PCODE_MB_PARAM2, p2);
270
271	with_intel_runtime_pm(uncore->rpm, wakeref)
272		err = snb_pcode_write(uncore, mbox, val);
273
274	return err;
275}
276