xref: /linux/drivers/gpu/drm/xe/xe_force_wake.c (revision 7f4f3b14e8079ecde096bd734af10e30d40c27b7)
1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright © 2022 Intel Corporation
4  */
5 
6 #include "xe_force_wake.h"
7 
8 #include <drm/drm_util.h>
9 
10 #include "regs/xe_gt_regs.h"
11 #include "regs/xe_reg_defs.h"
12 #include "xe_gt.h"
13 #include "xe_gt_printk.h"
14 #include "xe_mmio.h"
15 #include "xe_sriov.h"
16 
17 #define XE_FORCE_WAKE_ACK_TIMEOUT_MS	50
18 
19 static const char *str_wake_sleep(bool wake)
20 {
21 	return wake ? "wake" : "sleep";
22 }
23 
24 static void mark_domain_initialized(struct xe_force_wake *fw,
25 				    enum xe_force_wake_domain_id id)
26 {
27 	fw->initialized_domains |= BIT(id);
28 }
29 
30 static void init_domain(struct xe_force_wake *fw,
31 			enum xe_force_wake_domain_id id,
32 			struct xe_reg reg, struct xe_reg ack)
33 {
34 	struct xe_force_wake_domain *domain = &fw->domains[id];
35 
36 	domain->id = id;
37 	domain->reg_ctl = reg;
38 	domain->reg_ack = ack;
39 	domain->val = FORCEWAKE_MT(FORCEWAKE_KERNEL);
40 	domain->mask = FORCEWAKE_MT_MASK(FORCEWAKE_KERNEL);
41 
42 	mark_domain_initialized(fw, id);
43 }
44 
45 void xe_force_wake_init_gt(struct xe_gt *gt, struct xe_force_wake *fw)
46 {
47 	struct xe_device *xe = gt_to_xe(gt);
48 
49 	fw->gt = gt;
50 	spin_lock_init(&fw->lock);
51 
52 	/* Assuming gen11+ so assert this assumption is correct */
53 	xe_gt_assert(gt, GRAPHICS_VER(gt_to_xe(gt)) >= 11);
54 
55 	if (xe->info.graphics_verx100 >= 1270) {
56 		init_domain(fw, XE_FW_DOMAIN_ID_GT,
57 			    FORCEWAKE_GT,
58 			    FORCEWAKE_ACK_GT_MTL);
59 	} else {
60 		init_domain(fw, XE_FW_DOMAIN_ID_GT,
61 			    FORCEWAKE_GT,
62 			    FORCEWAKE_ACK_GT);
63 	}
64 }
65 
66 void xe_force_wake_init_engines(struct xe_gt *gt, struct xe_force_wake *fw)
67 {
68 	int i, j;
69 
70 	/* Assuming gen11+ so assert this assumption is correct */
71 	xe_gt_assert(gt, GRAPHICS_VER(gt_to_xe(gt)) >= 11);
72 
73 	if (!xe_gt_is_media_type(gt))
74 		init_domain(fw, XE_FW_DOMAIN_ID_RENDER,
75 			    FORCEWAKE_RENDER,
76 			    FORCEWAKE_ACK_RENDER);
77 
78 	for (i = XE_HW_ENGINE_VCS0, j = 0; i <= XE_HW_ENGINE_VCS7; ++i, ++j) {
79 		if (!(gt->info.engine_mask & BIT(i)))
80 			continue;
81 
82 		init_domain(fw, XE_FW_DOMAIN_ID_MEDIA_VDBOX0 + j,
83 			    FORCEWAKE_MEDIA_VDBOX(j),
84 			    FORCEWAKE_ACK_MEDIA_VDBOX(j));
85 	}
86 
87 	for (i = XE_HW_ENGINE_VECS0, j = 0; i <= XE_HW_ENGINE_VECS3; ++i, ++j) {
88 		if (!(gt->info.engine_mask & BIT(i)))
89 			continue;
90 
91 		init_domain(fw, XE_FW_DOMAIN_ID_MEDIA_VEBOX0 + j,
92 			    FORCEWAKE_MEDIA_VEBOX(j),
93 			    FORCEWAKE_ACK_MEDIA_VEBOX(j));
94 	}
95 
96 	if (gt->info.engine_mask & BIT(XE_HW_ENGINE_GSCCS0))
97 		init_domain(fw, XE_FW_DOMAIN_ID_GSC,
98 			    FORCEWAKE_GSC,
99 			    FORCEWAKE_ACK_GSC);
100 }
101 
102 static void __domain_ctl(struct xe_gt *gt, struct xe_force_wake_domain *domain, bool wake)
103 {
104 	if (IS_SRIOV_VF(gt_to_xe(gt)))
105 		return;
106 
107 	xe_mmio_write32(&gt->mmio, domain->reg_ctl, domain->mask | (wake ? domain->val : 0));
108 }
109 
110 static int __domain_wait(struct xe_gt *gt, struct xe_force_wake_domain *domain, bool wake)
111 {
112 	u32 value;
113 	int ret;
114 
115 	if (IS_SRIOV_VF(gt_to_xe(gt)))
116 		return 0;
117 
118 	ret = xe_mmio_wait32(&gt->mmio, domain->reg_ack, domain->val, wake ? domain->val : 0,
119 			     XE_FORCE_WAKE_ACK_TIMEOUT_MS * USEC_PER_MSEC,
120 			     &value, true);
121 	if (ret)
122 		xe_gt_err(gt, "Force wake domain %d failed to ack %s (%pe) reg[%#x] = %#x\n",
123 			  domain->id, str_wake_sleep(wake), ERR_PTR(ret),
124 			  domain->reg_ack.addr, value);
125 	if (value == ~0) {
126 		xe_gt_err(gt,
127 			  "Force wake domain %d: %s. MMIO unreliable (forcewake register returns 0xFFFFFFFF)!\n",
128 			  domain->id, str_wake_sleep(wake));
129 		ret = -EIO;
130 	}
131 
132 	return ret;
133 }
134 
135 static void domain_wake(struct xe_gt *gt, struct xe_force_wake_domain *domain)
136 {
137 	__domain_ctl(gt, domain, true);
138 }
139 
140 static int domain_wake_wait(struct xe_gt *gt,
141 			    struct xe_force_wake_domain *domain)
142 {
143 	return __domain_wait(gt, domain, true);
144 }
145 
146 static void domain_sleep(struct xe_gt *gt, struct xe_force_wake_domain *domain)
147 {
148 	__domain_ctl(gt, domain, false);
149 }
150 
151 static int domain_sleep_wait(struct xe_gt *gt,
152 			     struct xe_force_wake_domain *domain)
153 {
154 	return __domain_wait(gt, domain, false);
155 }
156 
157 #define for_each_fw_domain_masked(domain__, mask__, fw__, tmp__) \
158 	for (tmp__ = (mask__); tmp__; tmp__ &= ~BIT(ffs(tmp__) - 1)) \
159 		for_each_if((domain__ = ((fw__)->domains + \
160 					 (ffs(tmp__) - 1))) && \
161 					 domain__->reg_ctl.addr)
162 
163 /**
164  * xe_force_wake_get() : Increase the domain refcount
165  * @fw: struct xe_force_wake
166  * @domains: forcewake domains to get refcount on
167  *
168  * This function wakes up @domains if they are asleep and takes references.
169  * If requested domain is XE_FORCEWAKE_ALL then only applicable/initialized
170  * domains will be considered for refcount and it is a caller responsibility
171  * to check returned ref if it includes any specific domain by using
172  * xe_force_wake_ref_has_domain() function. Caller must call
173  * xe_force_wake_put() function to decrease incremented refcounts.
174  *
175  * Return: opaque reference to woken domains or zero if none of requested
176  * domains were awake.
177  */
178 unsigned int __must_check xe_force_wake_get(struct xe_force_wake *fw,
179 					    enum xe_force_wake_domains domains)
180 {
181 	struct xe_gt *gt = fw->gt;
182 	struct xe_force_wake_domain *domain;
183 	unsigned int ref_incr = 0, awake_rqst = 0, awake_failed = 0;
184 	unsigned int tmp, ref_rqst;
185 	unsigned long flags;
186 
187 	xe_gt_assert(gt, is_power_of_2(domains));
188 	xe_gt_assert(gt, domains <= XE_FORCEWAKE_ALL);
189 	xe_gt_assert(gt, domains == XE_FORCEWAKE_ALL || fw->initialized_domains & domains);
190 
191 	ref_rqst = (domains == XE_FORCEWAKE_ALL) ? fw->initialized_domains : domains;
192 	spin_lock_irqsave(&fw->lock, flags);
193 	for_each_fw_domain_masked(domain, ref_rqst, fw, tmp) {
194 		if (!domain->ref++) {
195 			awake_rqst |= BIT(domain->id);
196 			domain_wake(gt, domain);
197 		}
198 		ref_incr |= BIT(domain->id);
199 	}
200 	for_each_fw_domain_masked(domain, awake_rqst, fw, tmp) {
201 		if (domain_wake_wait(gt, domain) == 0) {
202 			fw->awake_domains |= BIT(domain->id);
203 		} else {
204 			awake_failed |= BIT(domain->id);
205 			--domain->ref;
206 		}
207 	}
208 	ref_incr &= ~awake_failed;
209 	spin_unlock_irqrestore(&fw->lock, flags);
210 
211 	xe_gt_WARN(gt, awake_failed, "Forcewake domain%s %#x failed to acknowledge awake request\n",
212 		   str_plural(hweight_long(awake_failed)), awake_failed);
213 
214 	if (domains == XE_FORCEWAKE_ALL && ref_incr == fw->initialized_domains)
215 		ref_incr |= XE_FORCEWAKE_ALL;
216 
217 	return ref_incr;
218 }
219 
220 /**
221  * xe_force_wake_put - Decrement the refcount and put domain to sleep if refcount becomes 0
222  * @fw: Pointer to the force wake structure
223  * @fw_ref: return of xe_force_wake_get()
224  *
225  * This function reduces the reference counts for domains in fw_ref. If
226  * refcount for any of the specified domain reaches 0, it puts the domain to sleep
227  * and waits for acknowledgment for domain to sleep within 50 milisec timeout.
228  * Warns in case of timeout of ack from domain.
229  */
230 void xe_force_wake_put(struct xe_force_wake *fw, unsigned int fw_ref)
231 {
232 	struct xe_gt *gt = fw->gt;
233 	struct xe_force_wake_domain *domain;
234 	unsigned int tmp, sleep = 0;
235 	unsigned long flags;
236 	int ack_fail = 0;
237 
238 	/*
239 	 * Avoid unnecessary lock and unlock when the function is called
240 	 * in error path of individual domains.
241 	 */
242 	if (!fw_ref)
243 		return;
244 
245 	if (xe_force_wake_ref_has_domain(fw_ref, XE_FORCEWAKE_ALL))
246 		fw_ref = fw->initialized_domains;
247 
248 	spin_lock_irqsave(&fw->lock, flags);
249 	for_each_fw_domain_masked(domain, fw_ref, fw, tmp) {
250 		xe_gt_assert(gt, domain->ref);
251 
252 		if (!--domain->ref) {
253 			sleep |= BIT(domain->id);
254 			domain_sleep(gt, domain);
255 		}
256 	}
257 	for_each_fw_domain_masked(domain, sleep, fw, tmp) {
258 		if (domain_sleep_wait(gt, domain) == 0)
259 			fw->awake_domains &= ~BIT(domain->id);
260 		else
261 			ack_fail |= BIT(domain->id);
262 	}
263 	spin_unlock_irqrestore(&fw->lock, flags);
264 
265 	xe_gt_WARN(gt, ack_fail, "Forcewake domain%s %#x failed to acknowledge sleep request\n",
266 		   str_plural(hweight_long(ack_fail)), ack_fail);
267 }
268