1 // SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
2 /*
3  * Copyright(c) 2021 Intel Corporation
4  */
5 
6 #include "iwl-drv.h"
7 #include "pnvm.h"
8 #include "iwl-prph.h"
9 #include "iwl-io.h"
10 
11 #include "fw/uefi.h"
12 #include "fw/api/alive.h"
13 #include <linux/efi.h>
14 
15 #define IWL_EFI_VAR_GUID EFI_GUID(0x92daaf2f, 0xc02b, 0x455b,	\
16 				  0xb2, 0xec, 0xf5, 0xa3,	\
17 				  0x59, 0x4f, 0x4a, 0xea)
18 
19 void *iwl_uefi_get_pnvm(struct iwl_trans *trans, size_t *len)
20 {
21 	struct efivar_entry *pnvm_efivar;
22 	void *data;
23 	unsigned long package_size;
24 	int err;
25 
26 	*len = 0;
27 
28 	pnvm_efivar = kzalloc(sizeof(*pnvm_efivar), GFP_KERNEL);
29 	if (!pnvm_efivar)
30 		return ERR_PTR(-ENOMEM);
31 
32 	memcpy(&pnvm_efivar->var.VariableName, IWL_UEFI_OEM_PNVM_NAME,
33 	       sizeof(IWL_UEFI_OEM_PNVM_NAME));
34 	pnvm_efivar->var.VendorGuid = IWL_EFI_VAR_GUID;
35 
36 	/*
37 	 * TODO: we hardcode a maximum length here, because reading
38 	 * from the UEFI is not working.  To implement this properly,
39 	 * we have to call efivar_entry_size().
40 	 */
41 	package_size = IWL_HARDCODED_PNVM_SIZE;
42 
43 	data = kmalloc(package_size, GFP_KERNEL);
44 	if (!data) {
45 		data = ERR_PTR(-ENOMEM);
46 		goto out;
47 	}
48 
49 	err = efivar_entry_get(pnvm_efivar, NULL, &package_size, data);
50 	if (err) {
51 		IWL_DEBUG_FW(trans,
52 			     "PNVM UEFI variable not found %d (len %lu)\n",
53 			     err, package_size);
54 		kfree(data);
55 		data = ERR_PTR(err);
56 		goto out;
57 	}
58 
59 	IWL_DEBUG_FW(trans, "Read PNVM from UEFI with size %lu\n", package_size);
60 	*len = package_size;
61 
62 out:
63 	kfree(pnvm_efivar);
64 
65 	return data;
66 }
67 
68 static void *iwl_uefi_reduce_power_section(struct iwl_trans *trans,
69 					   const u8 *data, size_t len)
70 {
71 	struct iwl_ucode_tlv *tlv;
72 	u8 *reduce_power_data = NULL, *tmp;
73 	u32 size = 0;
74 
75 	IWL_DEBUG_FW(trans, "Handling REDUCE_POWER section\n");
76 
77 	while (len >= sizeof(*tlv)) {
78 		u32 tlv_len, tlv_type;
79 
80 		len -= sizeof(*tlv);
81 		tlv = (void *)data;
82 
83 		tlv_len = le32_to_cpu(tlv->length);
84 		tlv_type = le32_to_cpu(tlv->type);
85 
86 		if (len < tlv_len) {
87 			IWL_ERR(trans, "invalid TLV len: %zd/%u\n",
88 				len, tlv_len);
89 			kfree(reduce_power_data);
90 			reduce_power_data = ERR_PTR(-EINVAL);
91 			goto out;
92 		}
93 
94 		data += sizeof(*tlv);
95 
96 		switch (tlv_type) {
97 		case IWL_UCODE_TLV_MEM_DESC: {
98 			IWL_DEBUG_FW(trans,
99 				     "Got IWL_UCODE_TLV_MEM_DESC len %d\n",
100 				     tlv_len);
101 
102 			IWL_DEBUG_FW(trans, "Adding data (size %d)\n", tlv_len);
103 
104 			tmp = krealloc(reduce_power_data, size + tlv_len, GFP_KERNEL);
105 			if (!tmp) {
106 				IWL_DEBUG_FW(trans,
107 					     "Couldn't allocate (more) reduce_power_data\n");
108 
109 				kfree(reduce_power_data);
110 				reduce_power_data = ERR_PTR(-ENOMEM);
111 				goto out;
112 			}
113 
114 			reduce_power_data = tmp;
115 
116 			memcpy(reduce_power_data + size, data, tlv_len);
117 
118 			size += tlv_len;
119 
120 			break;
121 		}
122 		case IWL_UCODE_TLV_PNVM_SKU:
123 			IWL_DEBUG_FW(trans,
124 				     "New REDUCE_POWER section started, stop parsing.\n");
125 			goto done;
126 		default:
127 			IWL_DEBUG_FW(trans, "Found TLV 0x%0x, len %d\n",
128 				     tlv_type, tlv_len);
129 			break;
130 		}
131 
132 		len -= ALIGN(tlv_len, 4);
133 		data += ALIGN(tlv_len, 4);
134 	}
135 
136 done:
137 	if (!size) {
138 		IWL_DEBUG_FW(trans, "Empty REDUCE_POWER, skipping.\n");
139 		/* Better safe than sorry, but 'reduce_power_data' should
140 		 * always be NULL if !size.
141 		 */
142 		kfree(reduce_power_data);
143 		reduce_power_data = ERR_PTR(-ENOENT);
144 		goto out;
145 	}
146 
147 	IWL_INFO(trans, "loaded REDUCE_POWER\n");
148 
149 out:
150 	return reduce_power_data;
151 }
152 
153 static void *iwl_uefi_reduce_power_parse(struct iwl_trans *trans,
154 					 const u8 *data, size_t len)
155 {
156 	struct iwl_ucode_tlv *tlv;
157 	void *sec_data;
158 
159 	IWL_DEBUG_FW(trans, "Parsing REDUCE_POWER data\n");
160 
161 	while (len >= sizeof(*tlv)) {
162 		u32 tlv_len, tlv_type;
163 
164 		len -= sizeof(*tlv);
165 		tlv = (void *)data;
166 
167 		tlv_len = le32_to_cpu(tlv->length);
168 		tlv_type = le32_to_cpu(tlv->type);
169 
170 		if (len < tlv_len) {
171 			IWL_ERR(trans, "invalid TLV len: %zd/%u\n",
172 				len, tlv_len);
173 			return ERR_PTR(-EINVAL);
174 		}
175 
176 		if (tlv_type == IWL_UCODE_TLV_PNVM_SKU) {
177 			struct iwl_sku_id *sku_id =
178 				(void *)(data + sizeof(*tlv));
179 
180 			IWL_DEBUG_FW(trans,
181 				     "Got IWL_UCODE_TLV_PNVM_SKU len %d\n",
182 				     tlv_len);
183 			IWL_DEBUG_FW(trans, "sku_id 0x%0x 0x%0x 0x%0x\n",
184 				     le32_to_cpu(sku_id->data[0]),
185 				     le32_to_cpu(sku_id->data[1]),
186 				     le32_to_cpu(sku_id->data[2]));
187 
188 			data += sizeof(*tlv) + ALIGN(tlv_len, 4);
189 			len -= ALIGN(tlv_len, 4);
190 
191 			if (trans->sku_id[0] == le32_to_cpu(sku_id->data[0]) &&
192 			    trans->sku_id[1] == le32_to_cpu(sku_id->data[1]) &&
193 			    trans->sku_id[2] == le32_to_cpu(sku_id->data[2])) {
194 				sec_data = iwl_uefi_reduce_power_section(trans,
195 									 data,
196 									 len);
197 				if (!IS_ERR(sec_data))
198 					return sec_data;
199 			} else {
200 				IWL_DEBUG_FW(trans, "SKU ID didn't match!\n");
201 			}
202 		} else {
203 			data += sizeof(*tlv) + ALIGN(tlv_len, 4);
204 			len -= ALIGN(tlv_len, 4);
205 		}
206 	}
207 
208 	return ERR_PTR(-ENOENT);
209 }
210 
211 void *iwl_uefi_get_reduced_power(struct iwl_trans *trans, size_t *len)
212 {
213 	struct efivar_entry *reduce_power_efivar;
214 	struct pnvm_sku_package *package;
215 	void *data = NULL;
216 	unsigned long package_size;
217 	int err;
218 
219 	*len = 0;
220 
221 	reduce_power_efivar = kzalloc(sizeof(*reduce_power_efivar), GFP_KERNEL);
222 	if (!reduce_power_efivar)
223 		return ERR_PTR(-ENOMEM);
224 
225 	memcpy(&reduce_power_efivar->var.VariableName, IWL_UEFI_REDUCED_POWER_NAME,
226 	       sizeof(IWL_UEFI_REDUCED_POWER_NAME));
227 	reduce_power_efivar->var.VendorGuid = IWL_EFI_VAR_GUID;
228 
229 	/*
230 	 * TODO: we hardcode a maximum length here, because reading
231 	 * from the UEFI is not working.  To implement this properly,
232 	 * we have to call efivar_entry_size().
233 	 */
234 	package_size = IWL_HARDCODED_REDUCE_POWER_SIZE;
235 
236 	package = kmalloc(package_size, GFP_KERNEL);
237 	if (!package) {
238 		package = ERR_PTR(-ENOMEM);
239 		goto out;
240 	}
241 
242 	err = efivar_entry_get(reduce_power_efivar, NULL, &package_size, package);
243 	if (err) {
244 		IWL_DEBUG_FW(trans,
245 			     "Reduced Power UEFI variable not found %d (len %lu)\n",
246 			     err, package_size);
247 		kfree(package);
248 		data = ERR_PTR(err);
249 		goto out;
250 	}
251 
252 	IWL_DEBUG_FW(trans, "Read reduced power from UEFI with size %lu\n",
253 		     package_size);
254 	*len = package_size;
255 
256 	IWL_DEBUG_FW(trans, "rev %d, total_size %d, n_skus %d\n",
257 		     package->rev, package->total_size, package->n_skus);
258 
259 	data = iwl_uefi_reduce_power_parse(trans, package->data,
260 					   *len - sizeof(*package));
261 
262 	kfree(package);
263 
264 out:
265 	kfree(reduce_power_efivar);
266 
267 	return data;
268 }
269