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_huc.h"
10 #include "i915_drv.h"
11 
intel_huc_init_early(struct intel_huc * huc)12 void intel_huc_init_early(struct intel_huc *huc)
13 {
14 	struct drm_i915_private *i915 = huc_to_gt(huc)->i915;
15 
16 	intel_huc_fw_init_early(huc);
17 
18 	if (INTEL_GEN(i915) >= 11) {
19 		huc->status.reg = GEN11_HUC_KERNEL_LOAD_INFO;
20 		huc->status.mask = HUC_LOAD_SUCCESSFUL;
21 		huc->status.value = HUC_LOAD_SUCCESSFUL;
22 	} else {
23 		huc->status.reg = HUC_STATUS2;
24 		huc->status.mask = HUC_FW_VERIFIED;
25 		huc->status.value = HUC_FW_VERIFIED;
26 	}
27 }
28 
intel_huc_rsa_data_create(struct intel_huc * huc)29 static int intel_huc_rsa_data_create(struct intel_huc *huc)
30 {
31 	struct intel_gt *gt = huc_to_gt(huc);
32 	struct intel_guc *guc = &gt->uc.guc;
33 	struct i915_vma *vma;
34 	size_t copied;
35 	void *vaddr;
36 	int err;
37 
38 	err = i915_inject_load_error(gt->i915, -ENXIO);
39 	if (err)
40 		return err;
41 
42 	/*
43 	 * HuC firmware will sit above GUC_GGTT_TOP and will not map
44 	 * through GTT. Unfortunately, this means GuC cannot perform
45 	 * the HuC auth. as the rsa offset now falls within the GuC
46 	 * inaccessible range. We resort to perma-pinning an additional
47 	 * vma within the accessible range that only contains the rsa
48 	 * signature. The GuC can use this extra pinning to perform
49 	 * the authentication since its GGTT offset will be GuC
50 	 * accessible.
51 	 */
52 	GEM_BUG_ON(huc->fw.rsa_size > PAGE_SIZE);
53 	vma = intel_guc_allocate_vma(guc, PAGE_SIZE);
54 	if (IS_ERR(vma))
55 		return PTR_ERR(vma);
56 
57 	vaddr = i915_gem_object_pin_map(vma->obj, I915_MAP_WB);
58 	if (IS_ERR(vaddr)) {
59 		i915_vma_unpin_and_release(&vma, 0);
60 		return PTR_ERR(vaddr);
61 	}
62 
63 	copied = intel_uc_fw_copy_rsa(&huc->fw, vaddr, vma->size);
64 	GEM_BUG_ON(copied < huc->fw.rsa_size);
65 
66 	i915_gem_object_unpin_map(vma->obj);
67 
68 	huc->rsa_data = vma;
69 
70 	return 0;
71 }
72 
intel_huc_rsa_data_destroy(struct intel_huc * huc)73 static void intel_huc_rsa_data_destroy(struct intel_huc *huc)
74 {
75 	i915_vma_unpin_and_release(&huc->rsa_data, 0);
76 }
77 
intel_huc_init(struct intel_huc * huc)78 int intel_huc_init(struct intel_huc *huc)
79 {
80 	struct drm_i915_private *i915 = huc_to_gt(huc)->i915;
81 	int err;
82 
83 	err = intel_uc_fw_init(&huc->fw);
84 	if (err)
85 		goto out;
86 
87 	/*
88 	 * HuC firmware image is outside GuC accessible range.
89 	 * Copy the RSA signature out of the image into
90 	 * a perma-pinned region set aside for it
91 	 */
92 	err = intel_huc_rsa_data_create(huc);
93 	if (err)
94 		goto out_fini;
95 
96 	return 0;
97 
98 out_fini:
99 	intel_uc_fw_fini(&huc->fw);
100 out:
101 	intel_uc_fw_cleanup_fetch(&huc->fw);
102 	DRM_DEV_DEBUG_DRIVER(i915->drm.dev, "failed with %d\n", err);
103 	return err;
104 }
105 
intel_huc_fini(struct intel_huc * huc)106 void intel_huc_fini(struct intel_huc *huc)
107 {
108 	if (!intel_uc_fw_is_available(&huc->fw))
109 		return;
110 
111 	intel_huc_rsa_data_destroy(huc);
112 	intel_uc_fw_fini(&huc->fw);
113 }
114 
115 /**
116  * intel_huc_auth() - Authenticate HuC uCode
117  * @huc: intel_huc structure
118  *
119  * Called after HuC and GuC firmware loading during intel_uc_init_hw().
120  *
121  * This function pins HuC firmware image object into GGTT.
122  * Then it invokes GuC action to authenticate passing the offset to RSA
123  * signature through intel_guc_auth_huc(). It then waits for 50ms for
124  * firmware verification ACK and unpins the object.
125  */
intel_huc_auth(struct intel_huc * huc)126 int intel_huc_auth(struct intel_huc *huc)
127 {
128 	struct intel_gt *gt = huc_to_gt(huc);
129 	struct intel_guc *guc = &gt->uc.guc;
130 	int ret;
131 
132 	GEM_BUG_ON(intel_huc_is_authenticated(huc));
133 
134 	if (!intel_uc_fw_is_loaded(&huc->fw))
135 		return -ENOEXEC;
136 
137 	ret = i915_inject_load_error(gt->i915, -ENXIO);
138 	if (ret)
139 		goto fail;
140 
141 	ret = intel_guc_auth_huc(guc,
142 				 intel_guc_ggtt_offset(guc, huc->rsa_data));
143 	if (ret) {
144 		DRM_ERROR("HuC: GuC did not ack Auth request %d\n", ret);
145 		goto fail;
146 	}
147 
148 	/* Check authentication status, it should be done by now */
149 	ret = __intel_wait_for_register(gt->uncore,
150 					huc->status.reg,
151 					huc->status.mask,
152 					huc->status.value,
153 					2, 50, NULL);
154 	if (ret) {
155 		DRM_ERROR("HuC: Firmware not verified %d\n", ret);
156 		goto fail;
157 	}
158 
159 	intel_uc_fw_change_status(&huc->fw, INTEL_UC_FIRMWARE_RUNNING);
160 	return 0;
161 
162 fail:
163 	i915_probe_error(gt->i915, "HuC: Authentication failed %d\n", ret);
164 	intel_uc_fw_change_status(&huc->fw, INTEL_UC_FIRMWARE_FAIL);
165 	return ret;
166 }
167 
168 /**
169  * intel_huc_check_status() - check HuC status
170  * @huc: intel_huc structure
171  *
172  * This function reads status register to verify if HuC
173  * firmware was successfully loaded.
174  *
175  * Returns: 1 if HuC firmware is loaded and verified,
176  * 0 if HuC firmware is not loaded and -ENODEV if HuC
177  * is not present on this platform.
178  */
intel_huc_check_status(struct intel_huc * huc)179 int intel_huc_check_status(struct intel_huc *huc)
180 {
181 	struct intel_gt *gt = huc_to_gt(huc);
182 	intel_wakeref_t wakeref;
183 	u32 status = 0;
184 
185 	if (!intel_huc_is_supported(huc))
186 		return -ENODEV;
187 
188 	with_intel_runtime_pm(&gt->i915->runtime_pm, wakeref)
189 		status = intel_uncore_read(gt->uncore, huc->status.reg);
190 
191 	return (status & huc->status.mask) == huc->status.value;
192 }
193