1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright © 2022 Intel Corporation
4  */
5 
6 #include <linux/types.h>
7 
8 #include "gt/intel_gt.h"
9 #include "gt/intel_gt_print.h"
10 #include "intel_gsc_fw.h"
11 #include "intel_gsc_proxy.h"
12 #include "intel_gsc_uc.h"
13 #include "i915_drv.h"
14 #include "i915_reg.h"
15 
16 static void gsc_work(struct work_struct *work)
17 {
18 	struct intel_gsc_uc *gsc = container_of(work, typeof(*gsc), work);
19 	struct intel_gt *gt = gsc_uc_to_gt(gsc);
20 	intel_wakeref_t wakeref;
21 	u32 actions;
22 	int ret;
23 
24 	wakeref = intel_runtime_pm_get(gt->uncore->rpm);
25 
26 	spin_lock_irq(gt->irq_lock);
27 	actions = gsc->gsc_work_actions;
28 	gsc->gsc_work_actions = 0;
29 	spin_unlock_irq(gt->irq_lock);
30 
31 	if (actions & GSC_ACTION_FW_LOAD) {
32 		ret = intel_gsc_uc_fw_upload(gsc);
33 		if (!ret)
34 			/* setup proxy on a new load */
35 			actions |= GSC_ACTION_SW_PROXY;
36 		else if (ret != -EEXIST)
37 			goto out_put;
38 
39 		/*
40 		 * The HuC auth can be done both before or after the proxy init;
41 		 * if done after, a proxy request will be issued and must be
42 		 * serviced before the authentication can complete.
43 		 * Since this worker also handles proxy requests, we can't
44 		 * perform an action that requires the proxy from within it and
45 		 * then stall waiting for it, because we'd be blocking the
46 		 * service path. Therefore, it is easier for us to load HuC
47 		 * first and do proxy later. The GSC will ack the HuC auth and
48 		 * then send the HuC proxy request as part of the proxy init
49 		 * flow.
50 		 * Note that we can only do the GSC auth if the GuC auth was
51 		 * successful.
52 		 */
53 		if (intel_uc_uses_huc(&gt->uc) &&
54 		    intel_huc_is_authenticated(&gt->uc.huc, INTEL_HUC_AUTH_BY_GUC))
55 			intel_huc_auth(&gt->uc.huc, INTEL_HUC_AUTH_BY_GSC);
56 	}
57 
58 	if (actions & GSC_ACTION_SW_PROXY) {
59 		if (!intel_gsc_uc_fw_init_done(gsc)) {
60 			gt_err(gt, "Proxy request received with GSC not loaded!\n");
61 			goto out_put;
62 		}
63 
64 		ret = intel_gsc_proxy_request_handler(gsc);
65 		if (ret)
66 			goto out_put;
67 
68 		/* mark the GSC FW init as done the first time we run this */
69 		if (actions & GSC_ACTION_FW_LOAD) {
70 			/*
71 			 * If there is a proxy establishment error, the GSC might still
72 			 * complete the request handling cleanly, so we need to check the
73 			 * status register to check if the proxy init was actually successful
74 			 */
75 			if (intel_gsc_uc_fw_proxy_init_done(gsc, false)) {
76 				drm_dbg(&gt->i915->drm, "GSC Proxy initialized\n");
77 				intel_uc_fw_change_status(&gsc->fw, INTEL_UC_FIRMWARE_RUNNING);
78 			} else {
79 				drm_err(&gt->i915->drm,
80 					"GSC status reports proxy init not complete\n");
81 			}
82 		}
83 	}
84 
85 out_put:
86 	intel_runtime_pm_put(gt->uncore->rpm, wakeref);
87 }
88 
89 static bool gsc_engine_supported(struct intel_gt *gt)
90 {
91 	intel_engine_mask_t mask;
92 
93 	/*
94 	 * We reach here from i915_driver_early_probe for the primary GT before
95 	 * its engine mask is set, so we use the device info engine mask for it.
96 	 * For other GTs we expect the GT-specific mask to be set before we
97 	 * call this function.
98 	 */
99 	GEM_BUG_ON(!gt_is_root(gt) && !gt->info.engine_mask);
100 
101 	if (gt_is_root(gt))
102 		mask = RUNTIME_INFO(gt->i915)->platform_engine_mask;
103 	else
104 		mask = gt->info.engine_mask;
105 
106 	return __HAS_ENGINE(mask, GSC0);
107 }
108 
109 void intel_gsc_uc_init_early(struct intel_gsc_uc *gsc)
110 {
111 	struct intel_gt *gt = gsc_uc_to_gt(gsc);
112 
113 	/*
114 	 * GSC FW needs to be copied to a dedicated memory allocations for
115 	 * loading (see gsc->local), so we don't need to GGTT map the FW image
116 	 * itself into GGTT.
117 	 */
118 	intel_uc_fw_init_early(&gsc->fw, INTEL_UC_FW_TYPE_GSC, false);
119 	INIT_WORK(&gsc->work, gsc_work);
120 
121 	/* we can arrive here from i915_driver_early_probe for primary
122 	 * GT with it being not fully setup hence check device info's
123 	 * engine mask
124 	 */
125 	if (!gsc_engine_supported(gt)) {
126 		intel_uc_fw_change_status(&gsc->fw, INTEL_UC_FIRMWARE_NOT_SUPPORTED);
127 		return;
128 	}
129 
130 	gsc->wq = alloc_ordered_workqueue("i915_gsc", 0);
131 	if (!gsc->wq) {
132 		gt_err(gt, "failed to allocate WQ for GSC, disabling FW\n");
133 		intel_uc_fw_change_status(&gsc->fw, INTEL_UC_FIRMWARE_NOT_SUPPORTED);
134 	}
135 }
136 
137 static int gsc_allocate_and_map_vma(struct intel_gsc_uc *gsc, u32 size)
138 {
139 	struct intel_gt *gt = gsc_uc_to_gt(gsc);
140 	struct drm_i915_gem_object *obj;
141 	struct i915_vma *vma;
142 	void __iomem *vaddr;
143 	int ret = 0;
144 
145 	/*
146 	 * The GSC FW doesn't immediately suspend after becoming idle, so there
147 	 * is a chance that it could still be awake after we successfully
148 	 * return from the  pci suspend function, even if there are no pending
149 	 * operations.
150 	 * The FW might therefore try to access memory for its suspend operation
151 	 * after the kernel has completed the HW suspend flow; this can cause
152 	 * issues if the FW is mapped in normal RAM memory, as some of the
153 	 * involved HW units might've already lost power.
154 	 * The driver must therefore avoid this situation and the recommended
155 	 * way to do so is to use stolen memory for the GSC memory allocation,
156 	 * because stolen memory takes a different path in HW and it is
157 	 * guaranteed to always work as long as the GPU itself is awake (which
158 	 * it must be if the GSC is awake).
159 	 */
160 	obj = i915_gem_object_create_stolen(gt->i915, size);
161 	if (IS_ERR(obj))
162 		return PTR_ERR(obj);
163 
164 	vma = i915_gem_object_ggtt_pin(obj, NULL, 0, 0, 0);
165 	if (IS_ERR(vma)) {
166 		ret = PTR_ERR(vma);
167 		goto err;
168 	}
169 
170 	vaddr = i915_vma_pin_iomap(vma);
171 	i915_vma_unpin(vma);
172 	if (IS_ERR(vaddr)) {
173 		ret = PTR_ERR(vaddr);
174 		goto err;
175 	}
176 
177 	i915_vma_make_unshrinkable(vma);
178 
179 	gsc->local = vma;
180 	gsc->local_vaddr = vaddr;
181 
182 	return 0;
183 
184 err:
185 	i915_gem_object_put(obj);
186 	return ret;
187 }
188 
189 static void gsc_unmap_and_free_vma(struct intel_gsc_uc *gsc)
190 {
191 	struct i915_vma *vma = fetch_and_zero(&gsc->local);
192 
193 	if (!vma)
194 		return;
195 
196 	gsc->local_vaddr = NULL;
197 	i915_vma_unpin_iomap(vma);
198 	i915_gem_object_put(vma->obj);
199 }
200 
201 int intel_gsc_uc_init(struct intel_gsc_uc *gsc)
202 {
203 	static struct lock_class_key gsc_lock;
204 	struct intel_gt *gt = gsc_uc_to_gt(gsc);
205 	struct intel_engine_cs *engine = gt->engine[GSC0];
206 	struct intel_context *ce;
207 	int err;
208 
209 	err = intel_uc_fw_init(&gsc->fw);
210 	if (err)
211 		goto out;
212 
213 	err = gsc_allocate_and_map_vma(gsc, SZ_4M);
214 	if (err)
215 		goto out_fw;
216 
217 	ce = intel_engine_create_pinned_context(engine, engine->gt->vm, SZ_4K,
218 						I915_GEM_HWS_GSC_ADDR,
219 						&gsc_lock, "gsc_context");
220 	if (IS_ERR(ce)) {
221 		gt_err(gt, "failed to create GSC CS ctx for FW communication\n");
222 		err =  PTR_ERR(ce);
223 		goto out_vma;
224 	}
225 
226 	gsc->ce = ce;
227 
228 	/* if we fail to init proxy we still want to load GSC for PM */
229 	intel_gsc_proxy_init(gsc);
230 
231 	intel_uc_fw_change_status(&gsc->fw, INTEL_UC_FIRMWARE_LOADABLE);
232 
233 	return 0;
234 
235 out_vma:
236 	gsc_unmap_and_free_vma(gsc);
237 out_fw:
238 	intel_uc_fw_fini(&gsc->fw);
239 out:
240 	gt_probe_error(gt, "GSC init failed %pe\n", ERR_PTR(err));
241 	return err;
242 }
243 
244 void intel_gsc_uc_fini(struct intel_gsc_uc *gsc)
245 {
246 	if (!intel_uc_fw_is_loadable(&gsc->fw))
247 		return;
248 
249 	flush_work(&gsc->work);
250 	if (gsc->wq) {
251 		destroy_workqueue(gsc->wq);
252 		gsc->wq = NULL;
253 	}
254 
255 	intel_gsc_proxy_fini(gsc);
256 
257 	if (gsc->ce)
258 		intel_engine_destroy_pinned_context(fetch_and_zero(&gsc->ce));
259 
260 	gsc_unmap_and_free_vma(gsc);
261 
262 	intel_uc_fw_fini(&gsc->fw);
263 }
264 
265 void intel_gsc_uc_flush_work(struct intel_gsc_uc *gsc)
266 {
267 	if (!intel_uc_fw_is_loadable(&gsc->fw))
268 		return;
269 
270 	flush_work(&gsc->work);
271 }
272 
273 void intel_gsc_uc_resume(struct intel_gsc_uc *gsc)
274 {
275 	if (!intel_uc_fw_is_loadable(&gsc->fw))
276 		return;
277 
278 	/*
279 	 * we only want to start the GSC worker from here in the actual resume
280 	 * flow and not during driver load. This is because GSC load is slow and
281 	 * therefore we want to make sure that the default state init completes
282 	 * first to not slow down the init thread. A separate call to
283 	 * intel_gsc_uc_load_start will ensure that the GSC is loaded during
284 	 * driver load.
285 	 */
286 	if (!gsc_uc_to_gt(gsc)->engine[GSC0]->default_state)
287 		return;
288 
289 	intel_gsc_uc_load_start(gsc);
290 }
291 
292 void intel_gsc_uc_load_start(struct intel_gsc_uc *gsc)
293 {
294 	struct intel_gt *gt = gsc_uc_to_gt(gsc);
295 
296 	if (!intel_uc_fw_is_loadable(&gsc->fw))
297 		return;
298 
299 	if (intel_gsc_uc_fw_init_done(gsc))
300 		return;
301 
302 	spin_lock_irq(gt->irq_lock);
303 	gsc->gsc_work_actions |= GSC_ACTION_FW_LOAD;
304 	spin_unlock_irq(gt->irq_lock);
305 
306 	queue_work(gsc->wq, &gsc->work);
307 }
308 
309 void intel_gsc_uc_load_status(struct intel_gsc_uc *gsc, struct drm_printer *p)
310 {
311 	struct intel_gt *gt = gsc_uc_to_gt(gsc);
312 	struct intel_uncore *uncore = gt->uncore;
313 	intel_wakeref_t wakeref;
314 
315 	if (!intel_gsc_uc_is_supported(gsc)) {
316 		drm_printf(p, "GSC not supported\n");
317 		return;
318 	}
319 
320 	if (!intel_gsc_uc_is_wanted(gsc)) {
321 		drm_printf(p, "GSC disabled\n");
322 		return;
323 	}
324 
325 	drm_printf(p, "GSC firmware: %s\n", gsc->fw.file_selected.path);
326 	if (gsc->fw.file_selected.path != gsc->fw.file_wanted.path)
327 		drm_printf(p, "GSC firmware wanted: %s\n", gsc->fw.file_wanted.path);
328 	drm_printf(p, "\tstatus: %s\n", intel_uc_fw_status_repr(gsc->fw.status));
329 
330 	drm_printf(p, "Release: %u.%u.%u.%u\n",
331 		   gsc->release.major, gsc->release.minor,
332 		   gsc->release.patch, gsc->release.build);
333 
334 	drm_printf(p, "Compatibility Version: %u.%u [min expected %u.%u]\n",
335 		   gsc->fw.file_selected.ver.major, gsc->fw.file_selected.ver.minor,
336 		   gsc->fw.file_wanted.ver.major, gsc->fw.file_wanted.ver.minor);
337 
338 	drm_printf(p, "SVN: %u\n", gsc->security_version);
339 
340 	with_intel_runtime_pm(uncore->rpm, wakeref) {
341 		u32 i;
342 
343 		for (i = 1; i <= 6; i++) {
344 			u32 status = intel_uncore_read(uncore,
345 						       HECI_FWSTS(MTL_GSC_HECI1_BASE, i));
346 			drm_printf(p, "HECI1 FWSTST%u = 0x%08x\n", i, status);
347 		}
348 	}
349 }
350