x86, microcode, AMD: Exit early on success
[firefly-linux-kernel-4.4.55.git] / arch / x86 / kernel / microcode_amd.c
1 /*
2  *  AMD CPU Microcode Update Driver for Linux
3  *  Copyright (C) 2008 Advanced Micro Devices Inc.
4  *
5  *  Author: Peter Oruba <peter.oruba@amd.com>
6  *
7  *  Based on work by:
8  *  Tigran Aivazian <tigran@aivazian.fsnet.co.uk>
9  *
10  *  This driver allows to upgrade microcode on AMD
11  *  family 0x10 and 0x11 processors.
12  *
13  *  Licensed under the terms of the GNU General Public
14  *  License version 2. See file COPYING for details.
15  */
16
17 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
18
19 #include <linux/firmware.h>
20 #include <linux/pci_ids.h>
21 #include <linux/uaccess.h>
22 #include <linux/vmalloc.h>
23 #include <linux/kernel.h>
24 #include <linux/module.h>
25 #include <linux/pci.h>
26
27 #include <asm/microcode.h>
28 #include <asm/processor.h>
29 #include <asm/msr.h>
30
31 MODULE_DESCRIPTION("AMD Microcode Update Driver");
32 MODULE_AUTHOR("Peter Oruba");
33 MODULE_LICENSE("GPL v2");
34
35 #define UCODE_MAGIC                0x00414d44
36 #define UCODE_EQUIV_CPU_TABLE_TYPE 0x00000000
37 #define UCODE_UCODE_TYPE           0x00000001
38
39 struct equiv_cpu_entry {
40         u32     installed_cpu;
41         u32     fixed_errata_mask;
42         u32     fixed_errata_compare;
43         u16     equiv_cpu;
44         u16     res;
45 } __attribute__((packed));
46
47 struct microcode_header_amd {
48         u32     data_code;
49         u32     patch_id;
50         u16     mc_patch_data_id;
51         u8      mc_patch_data_len;
52         u8      init_flag;
53         u32     mc_patch_data_checksum;
54         u32     nb_dev_id;
55         u32     sb_dev_id;
56         u16     processor_rev_id;
57         u8      nb_rev_id;
58         u8      sb_rev_id;
59         u8      bios_api_rev;
60         u8      reserved1[3];
61         u32     match_reg[8];
62 } __attribute__((packed));
63
64 struct microcode_amd {
65         struct microcode_header_amd     hdr;
66         unsigned int                    mpb[0];
67 };
68
69 #define SECTION_HDR_SIZE        8
70 #define CONTAINER_HDR_SZ        12
71
72 static struct equiv_cpu_entry *equiv_cpu_table;
73
74 /* page-sized ucode patch buffer */
75 void *patch;
76
77 static int collect_cpu_info_amd(int cpu, struct cpu_signature *csig)
78 {
79         struct cpuinfo_x86 *c = &cpu_data(cpu);
80
81         if (c->x86_vendor != X86_VENDOR_AMD || c->x86 < 0x10) {
82                 pr_warning("CPU%d: family %d not supported\n", cpu, c->x86);
83                 return -1;
84         }
85
86         csig->rev = c->microcode;
87         pr_info("CPU%d: patch_level=0x%08x\n", cpu, csig->rev);
88
89         return 0;
90 }
91
92 static unsigned int verify_ucode_size(int cpu, u32 patch_size,
93                                       unsigned int size)
94 {
95         struct cpuinfo_x86 *c = &cpu_data(cpu);
96         u32 max_size;
97
98 #define F1XH_MPB_MAX_SIZE 2048
99 #define F14H_MPB_MAX_SIZE 1824
100 #define F15H_MPB_MAX_SIZE 4096
101
102         switch (c->x86) {
103         case 0x14:
104                 max_size = F14H_MPB_MAX_SIZE;
105                 break;
106         case 0x15:
107                 max_size = F15H_MPB_MAX_SIZE;
108                 break;
109         default:
110                 max_size = F1XH_MPB_MAX_SIZE;
111                 break;
112         }
113
114         if (patch_size > min_t(u32, size, max_size)) {
115                 pr_err("patch size mismatch\n");
116                 return 0;
117         }
118
119         return patch_size;
120 }
121
122 static u16 find_equiv_id(void)
123 {
124         unsigned int current_cpu_id, i = 0;
125
126         BUG_ON(equiv_cpu_table == NULL);
127
128         current_cpu_id = cpuid_eax(0x00000001);
129
130         while (equiv_cpu_table[i].installed_cpu != 0) {
131                 if (current_cpu_id == equiv_cpu_table[i].installed_cpu)
132                         return equiv_cpu_table[i].equiv_cpu;
133
134                 i++;
135         }
136         return 0;
137 }
138
139 /*
140  * we signal a good patch is found by returning its size > 0
141  */
142 static int get_matching_microcode(int cpu, const u8 *ucode_ptr,
143                                   unsigned int leftover_size, int rev,
144                                   unsigned int *current_size)
145 {
146         struct microcode_header_amd *mc_hdr;
147         unsigned int actual_size;
148         u16 equiv_cpu_id;
149
150         /* size of the current patch we're staring at */
151         *current_size = *(u32 *)(ucode_ptr + 4) + SECTION_HDR_SIZE;
152
153         equiv_cpu_id = find_equiv_id();
154         if (!equiv_cpu_id)
155                 return 0;
156
157         /*
158          * let's look at the patch header itself now
159          */
160         mc_hdr = (struct microcode_header_amd *)(ucode_ptr + SECTION_HDR_SIZE);
161
162         if (mc_hdr->processor_rev_id != equiv_cpu_id)
163                 return 0;
164
165         /* ucode might be chipset specific -- currently we don't support this */
166         if (mc_hdr->nb_dev_id || mc_hdr->sb_dev_id) {
167                 pr_err("CPU%d: chipset specific code not yet supported\n",
168                        cpu);
169                 return 0;
170         }
171
172         if (mc_hdr->patch_id <= rev)
173                 return 0;
174
175         /*
176          * now that the header looks sane, verify its size
177          */
178         actual_size = verify_ucode_size(cpu, *current_size, leftover_size);
179         if (!actual_size)
180                 return 0;
181
182         /* clear the patch buffer */
183         memset(patch, 0, PAGE_SIZE);
184
185         /* all looks ok, get the binary patch */
186         get_ucode_data(patch, ucode_ptr + SECTION_HDR_SIZE, actual_size);
187
188         return actual_size;
189 }
190
191 static int apply_microcode_amd(int cpu)
192 {
193         u32 rev, dummy;
194         int cpu_num = raw_smp_processor_id();
195         struct ucode_cpu_info *uci = ucode_cpu_info + cpu_num;
196         struct microcode_amd *mc_amd = uci->mc;
197         struct cpuinfo_x86 *c = &cpu_data(cpu);
198
199         /* We should bind the task to the CPU */
200         BUG_ON(cpu_num != cpu);
201
202         if (mc_amd == NULL)
203                 return 0;
204
205         wrmsrl(MSR_AMD64_PATCH_LOADER, (u64)(long)&mc_amd->hdr.data_code);
206         /* get patch id after patching */
207         rdmsr(MSR_AMD64_PATCH_LEVEL, rev, dummy);
208
209         /* check current patch id and patch's id for match */
210         if (rev != mc_amd->hdr.patch_id) {
211                 pr_err("CPU%d: update failed for patch_level=0x%08x\n",
212                        cpu, mc_amd->hdr.patch_id);
213                 return -1;
214         }
215
216         pr_info("CPU%d: new patch_level=0x%08x\n", cpu, rev);
217         uci->cpu_sig.rev = rev;
218         c->microcode = rev;
219
220         return 0;
221 }
222
223 static int install_equiv_cpu_table(const u8 *buf)
224 {
225         unsigned int *ibuf = (unsigned int *)buf;
226         unsigned int type = ibuf[1];
227         unsigned int size = ibuf[2];
228
229         if (type != UCODE_EQUIV_CPU_TABLE_TYPE || !size) {
230                 pr_err("empty section/"
231                        "invalid type field in container file section header\n");
232                 return -EINVAL;
233         }
234
235         equiv_cpu_table = vmalloc(size);
236         if (!equiv_cpu_table) {
237                 pr_err("failed to allocate equivalent CPU table\n");
238                 return -ENOMEM;
239         }
240
241         get_ucode_data(equiv_cpu_table, buf + CONTAINER_HDR_SZ, size);
242
243         /* add header length */
244         return size + CONTAINER_HDR_SZ;
245 }
246
247 static void free_equiv_cpu_table(void)
248 {
249         vfree(equiv_cpu_table);
250         equiv_cpu_table = NULL;
251 }
252
253 static enum ucode_state
254 generic_load_microcode(int cpu, const u8 *data, size_t size)
255 {
256         struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
257         struct microcode_header_amd *mc_hdr = NULL;
258         unsigned int mc_size, leftover, current_size = 0;
259         int offset;
260         const u8 *ucode_ptr = data;
261         void *new_mc = NULL;
262         unsigned int new_rev = uci->cpu_sig.rev;
263         enum ucode_state state = UCODE_ERROR;
264
265         offset = install_equiv_cpu_table(ucode_ptr);
266         if (offset < 0) {
267                 pr_err("failed to create equivalent cpu table\n");
268                 goto out;
269         }
270         ucode_ptr += offset;
271         leftover = size - offset;
272
273         if (*(u32 *)ucode_ptr != UCODE_UCODE_TYPE) {
274                 pr_err("invalid type field in container file section header\n");
275                 goto free_table;
276         }
277
278         while (leftover) {
279                 mc_size = get_matching_microcode(cpu, ucode_ptr, leftover,
280                                                  new_rev, &current_size);
281                 if (mc_size) {
282                         mc_hdr  = patch;
283                         new_mc  = patch;
284                         new_rev = mc_hdr->patch_id;
285                         goto out_ok;
286                 }
287
288                 ucode_ptr += current_size;
289                 leftover  -= current_size;
290         }
291
292         if (!new_mc) {
293                 state = UCODE_NFOUND;
294                 goto free_table;
295         }
296
297 out_ok:
298         uci->mc = new_mc;
299         state = UCODE_OK;
300         pr_debug("CPU%d update ucode (0x%08x -> 0x%08x)\n",
301                  cpu, uci->cpu_sig.rev, new_rev);
302
303 free_table:
304         free_equiv_cpu_table();
305
306 out:
307         return state;
308 }
309
310 static enum ucode_state request_microcode_amd(int cpu, struct device *device)
311 {
312         const char *fw_name = "amd-ucode/microcode_amd.bin";
313         const struct firmware *fw;
314         enum ucode_state ret = UCODE_NFOUND;
315
316         if (request_firmware(&fw, fw_name, device)) {
317                 pr_err("failed to load file %s\n", fw_name);
318                 goto out;
319         }
320
321         ret = UCODE_ERROR;
322         if (*(u32 *)fw->data != UCODE_MAGIC) {
323                 pr_err("invalid magic value (0x%08x)\n", *(u32 *)fw->data);
324                 goto fw_release;
325         }
326
327         ret = generic_load_microcode(cpu, fw->data, fw->size);
328
329 fw_release:
330         release_firmware(fw);
331
332 out:
333         return ret;
334 }
335
336 static enum ucode_state
337 request_microcode_user(int cpu, const void __user *buf, size_t size)
338 {
339         pr_info("AMD microcode update via /dev/cpu/microcode not supported\n");
340         return UCODE_ERROR;
341 }
342
343 static void microcode_fini_cpu_amd(int cpu)
344 {
345         struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
346
347         uci->mc = NULL;
348 }
349
350 static struct microcode_ops microcode_amd_ops = {
351         .request_microcode_user           = request_microcode_user,
352         .request_microcode_fw             = request_microcode_amd,
353         .collect_cpu_info                 = collect_cpu_info_amd,
354         .apply_microcode                  = apply_microcode_amd,
355         .microcode_fini_cpu               = microcode_fini_cpu_amd,
356 };
357
358 struct microcode_ops * __init init_amd_microcode(void)
359 {
360         patch = (void *)get_zeroed_page(GFP_KERNEL);
361         if (!patch)
362                 return NULL;
363
364         return &microcode_amd_ops;
365 }
366
367 void __exit exit_amd_microcode(void)
368 {
369         free_page((unsigned long)patch);
370 }