1 // SPDX-License-Identifier: MIT
2 /*
3 * Copyright © 2016-2019 Intel Corporation
4 */
5
6 #include <linux/types.h>
7
8 #include "gt/intel_gt.h"
9 #include "intel_guc_reg.h"
10 #include "intel_huc.h"
11 #include "i915_drv.h"
12
13 /**
14 * DOC: HuC
15 *
16 * The HuC is a dedicated microcontroller for usage in media HEVC (High
17 * Efficiency Video Coding) operations. Userspace can directly use the firmware
18 * capabilities by adding HuC specific commands to batch buffers.
19 *
20 * The kernel driver is only responsible for loading the HuC firmware and
21 * triggering its security authentication, which is performed by the GuC on
22 * older platforms and by the GSC on newer ones. For the GuC to correctly
23 * perform the authentication, the HuC binary must be loaded before the GuC one.
24 * Loading the HuC is optional; however, not using the HuC might negatively
25 * impact power usage and/or performance of media workloads, depending on the
26 * use-cases.
27 * HuC must be reloaded on events that cause the WOPCM to lose its contents
28 * (S3/S4, FLR); GuC-authenticated HuC must also be reloaded on GuC/GT reset,
29 * while GSC-managed HuC will survive that.
30 *
31 * See https://github.com/intel/media-driver for the latest details on HuC
32 * functionality.
33 */
34
35 /**
36 * DOC: HuC Memory Management
37 *
38 * Similarly to the GuC, the HuC can't do any memory allocations on its own,
39 * with the difference being that the allocations for HuC usage are handled by
40 * the userspace driver instead of the kernel one. The HuC accesses the memory
41 * via the PPGTT belonging to the context loaded on the VCS executing the
42 * HuC-specific commands.
43 */
44
intel_huc_init_early(struct intel_huc * huc)45 void intel_huc_init_early(struct intel_huc *huc)
46 {
47 struct drm_i915_private *i915 = huc_to_gt(huc)->i915;
48
49 intel_uc_fw_init_early(&huc->fw, INTEL_UC_FW_TYPE_HUC);
50
51 if (GRAPHICS_VER(i915) >= 11) {
52 huc->status.reg = GEN11_HUC_KERNEL_LOAD_INFO;
53 huc->status.mask = HUC_LOAD_SUCCESSFUL;
54 huc->status.value = HUC_LOAD_SUCCESSFUL;
55 } else {
56 huc->status.reg = HUC_STATUS2;
57 huc->status.mask = HUC_FW_VERIFIED;
58 huc->status.value = HUC_FW_VERIFIED;
59 }
60 }
61
62 #define HUC_LOAD_MODE_STRING(x) (x ? "GSC" : "legacy")
check_huc_loading_mode(struct intel_huc * huc)63 static int check_huc_loading_mode(struct intel_huc *huc)
64 {
65 struct intel_gt *gt = huc_to_gt(huc);
66 bool fw_needs_gsc = intel_huc_is_loaded_by_gsc(huc);
67 bool hw_uses_gsc = false;
68
69 /*
70 * The fuse for HuC load via GSC is only valid on platforms that have
71 * GuC deprivilege.
72 */
73 if (HAS_GUC_DEPRIVILEGE(gt->i915))
74 hw_uses_gsc = intel_uncore_read(gt->uncore, GUC_SHIM_CONTROL2) &
75 GSC_LOADS_HUC;
76
77 if (fw_needs_gsc != hw_uses_gsc) {
78 drm_err(>->i915->drm,
79 "mismatch between HuC FW (%s) and HW (%s) load modes\n",
80 HUC_LOAD_MODE_STRING(fw_needs_gsc),
81 HUC_LOAD_MODE_STRING(hw_uses_gsc));
82 return -ENOEXEC;
83 }
84
85 /* make sure we can access the GSC via the mei driver if we need it */
86 if (!(IS_ENABLED(CONFIG_INTEL_MEI_PXP) && IS_ENABLED(CONFIG_INTEL_MEI_GSC)) &&
87 fw_needs_gsc) {
88 drm_info(>->i915->drm,
89 "Can't load HuC due to missing MEI modules\n");
90 return -EIO;
91 }
92
93 drm_dbg(>->i915->drm, "GSC loads huc=%s\n", str_yes_no(fw_needs_gsc));
94
95 return 0;
96 }
97
intel_huc_init(struct intel_huc * huc)98 int intel_huc_init(struct intel_huc *huc)
99 {
100 struct drm_i915_private *i915 = huc_to_gt(huc)->i915;
101 int err;
102
103 err = check_huc_loading_mode(huc);
104 if (err)
105 goto out;
106
107 err = intel_uc_fw_init(&huc->fw);
108 if (err)
109 goto out;
110
111 intel_uc_fw_change_status(&huc->fw, INTEL_UC_FIRMWARE_LOADABLE);
112
113 return 0;
114
115 out:
116 drm_info(&i915->drm, "HuC init failed with %d\n", err);
117 return err;
118 }
119
intel_huc_fini(struct intel_huc * huc)120 void intel_huc_fini(struct intel_huc *huc)
121 {
122 if (!intel_uc_fw_is_loadable(&huc->fw))
123 return;
124
125 intel_uc_fw_fini(&huc->fw);
126 }
127
128 /**
129 * intel_huc_auth() - Authenticate HuC uCode
130 * @huc: intel_huc structure
131 *
132 * Called after HuC and GuC firmware loading during intel_uc_init_hw().
133 *
134 * This function invokes the GuC action to authenticate the HuC firmware,
135 * passing the offset of the RSA signature to intel_guc_auth_huc(). It then
136 * waits for up to 50ms for firmware verification ACK.
137 */
intel_huc_auth(struct intel_huc * huc)138 int intel_huc_auth(struct intel_huc *huc)
139 {
140 struct intel_gt *gt = huc_to_gt(huc);
141 struct intel_guc *guc = >->uc.guc;
142 int ret;
143
144 if (!intel_uc_fw_is_loaded(&huc->fw))
145 return -ENOEXEC;
146
147 /* GSC will do the auth */
148 if (intel_huc_is_loaded_by_gsc(huc))
149 return -ENODEV;
150
151 ret = i915_inject_probe_error(gt->i915, -ENXIO);
152 if (ret)
153 goto fail;
154
155 GEM_BUG_ON(intel_uc_fw_is_running(&huc->fw));
156
157 ret = intel_guc_auth_huc(guc, intel_guc_ggtt_offset(guc, huc->fw.rsa_data));
158 if (ret) {
159 DRM_ERROR("HuC: GuC did not ack Auth request %d\n", ret);
160 goto fail;
161 }
162
163 /* Check authentication status, it should be done by now */
164 ret = __intel_wait_for_register(gt->uncore,
165 huc->status.reg,
166 huc->status.mask,
167 huc->status.value,
168 2, 50, NULL);
169 if (ret) {
170 DRM_ERROR("HuC: Firmware not verified %d\n", ret);
171 goto fail;
172 }
173
174 intel_uc_fw_change_status(&huc->fw, INTEL_UC_FIRMWARE_RUNNING);
175 drm_info(>->i915->drm, "HuC authenticated\n");
176 return 0;
177
178 fail:
179 i915_probe_error(gt->i915, "HuC: Authentication failed %d\n", ret);
180 intel_uc_fw_change_status(&huc->fw, INTEL_UC_FIRMWARE_LOAD_FAIL);
181 return ret;
182 }
183
huc_is_authenticated(struct intel_huc * huc)184 static bool huc_is_authenticated(struct intel_huc *huc)
185 {
186 struct intel_gt *gt = huc_to_gt(huc);
187 intel_wakeref_t wakeref;
188 u32 status = 0;
189
190 with_intel_runtime_pm(gt->uncore->rpm, wakeref)
191 status = intel_uncore_read(gt->uncore, huc->status.reg);
192
193 return (status & huc->status.mask) == huc->status.value;
194 }
195
196 /**
197 * intel_huc_check_status() - check HuC status
198 * @huc: intel_huc structure
199 *
200 * This function reads status register to verify if HuC
201 * firmware was successfully loaded.
202 *
203 * Returns:
204 * * -ENODEV if HuC is not present on this platform,
205 * * -EOPNOTSUPP if HuC firmware is disabled,
206 * * -ENOPKG if HuC firmware was not installed,
207 * * -ENOEXEC if HuC firmware is invalid or mismatched,
208 * * 0 if HuC firmware is not running,
209 * * 1 if HuC firmware is authenticated and running.
210 */
intel_huc_check_status(struct intel_huc * huc)211 int intel_huc_check_status(struct intel_huc *huc)
212 {
213 switch (__intel_uc_fw_status(&huc->fw)) {
214 case INTEL_UC_FIRMWARE_NOT_SUPPORTED:
215 return -ENODEV;
216 case INTEL_UC_FIRMWARE_DISABLED:
217 return -EOPNOTSUPP;
218 case INTEL_UC_FIRMWARE_MISSING:
219 return -ENOPKG;
220 case INTEL_UC_FIRMWARE_ERROR:
221 return -ENOEXEC;
222 default:
223 break;
224 }
225
226 return huc_is_authenticated(huc);
227 }
228
intel_huc_update_auth_status(struct intel_huc * huc)229 void intel_huc_update_auth_status(struct intel_huc *huc)
230 {
231 if (!intel_uc_fw_is_loadable(&huc->fw))
232 return;
233
234 if (huc_is_authenticated(huc))
235 intel_uc_fw_change_status(&huc->fw,
236 INTEL_UC_FIRMWARE_RUNNING);
237 }
238
239 /**
240 * intel_huc_load_status - dump information about HuC load status
241 * @huc: the HuC
242 * @p: the &drm_printer
243 *
244 * Pretty printer for HuC load status.
245 */
intel_huc_load_status(struct intel_huc * huc,struct drm_printer * p)246 void intel_huc_load_status(struct intel_huc *huc, struct drm_printer *p)
247 {
248 struct intel_gt *gt = huc_to_gt(huc);
249 intel_wakeref_t wakeref;
250
251 if (!intel_huc_is_supported(huc)) {
252 drm_printf(p, "HuC not supported\n");
253 return;
254 }
255
256 if (!intel_huc_is_wanted(huc)) {
257 drm_printf(p, "HuC disabled\n");
258 return;
259 }
260
261 intel_uc_fw_dump(&huc->fw, p);
262
263 with_intel_runtime_pm(gt->uncore->rpm, wakeref)
264 drm_printf(p, "HuC status: 0x%08x\n",
265 intel_uncore_read(gt->uncore, huc->status.reg));
266 }
267