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authorLinus Torvalds <torvalds@linux-foundation.org>2021-04-26 19:09:18 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2021-04-26 19:09:18 +0300
commit98ee795b21733a370bfdb3ba4359d2e31e6db514 (patch)
tree61c5008625eebde02dfde1ca8acd25bd64faad76 /tools/arch/x86/kcpuid/kcpuid.c
parent2c5ce2dba26afb39d426d9c06fd1c8e5057936d7 (diff)
parentf281854fa743f3474b2d0d69533301f48cf0e184 (diff)
downloadlinux-98ee795b21733a370bfdb3ba4359d2e31e6db514.tar.xz
Merge tag 'x86_misc_for_v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 tool update from Borislav Petkov: "A new kcpuid tool to dump the raw CPUID leafs of a CPU. It has the CPUID bit definitions in a separate csv file which allows for adding support for new CPUID leafs and bits without having to update the tool. The main use case for the tool is hw enablement on preproduction x86 hardware" * tag 'x86_misc_for_v5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: tools/x86/kcpuid: Add AMD leaf 0x8000001E tools/x86/kcpuid: Check last token too selftests/x86: Add a missing .note.GNU-stack section to thunks_32.S tools/x86/kcpuid: Add AMD Secure Encryption leaf tools/x86: Add a kcpuid tool to show raw CPU features
Diffstat (limited to 'tools/arch/x86/kcpuid/kcpuid.c')
-rw-r--r--tools/arch/x86/kcpuid/kcpuid.c657
1 files changed, 657 insertions, 0 deletions
diff --git a/tools/arch/x86/kcpuid/kcpuid.c b/tools/arch/x86/kcpuid/kcpuid.c
new file mode 100644
index 000000000000..dae75511fef7
--- /dev/null
+++ b/tools/arch/x86/kcpuid/kcpuid.c
@@ -0,0 +1,657 @@
+// SPDX-License-Identifier: GPL-2.0
+#define _GNU_SOURCE
+
+#include <stdio.h>
+#include <stdbool.h>
+#include <stdlib.h>
+#include <string.h>
+#include <getopt.h>
+
+#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
+
+typedef unsigned int u32;
+typedef unsigned long long u64;
+
+char *def_csv = "/usr/share/misc/cpuid.csv";
+char *user_csv;
+
+
+/* Cover both single-bit flag and multiple-bits fields */
+struct bits_desc {
+ /* start and end bits */
+ int start, end;
+ /* 0 or 1 for 1-bit flag */
+ int value;
+ char simp[32];
+ char detail[256];
+};
+
+/* descriptor info for eax/ebx/ecx/edx */
+struct reg_desc {
+ /* number of valid entries */
+ int nr;
+ struct bits_desc descs[32];
+};
+
+enum {
+ R_EAX = 0,
+ R_EBX,
+ R_ECX,
+ R_EDX,
+ NR_REGS
+};
+
+struct subleaf {
+ u32 index;
+ u32 sub;
+ u32 eax, ebx, ecx, edx;
+ struct reg_desc info[NR_REGS];
+};
+
+/* Represent one leaf (basic or extended) */
+struct cpuid_func {
+ /*
+ * Array of subleafs for this func, if there is no subleafs
+ * then the leafs[0] is the main leaf
+ */
+ struct subleaf *leafs;
+ int nr;
+};
+
+struct cpuid_range {
+ /* array of main leafs */
+ struct cpuid_func *funcs;
+ /* number of valid leafs */
+ int nr;
+ bool is_ext;
+};
+
+/*
+ * basic: basic functions range: [0... ]
+ * ext: extended functions range: [0x80000000... ]
+ */
+struct cpuid_range *leafs_basic, *leafs_ext;
+
+static int num_leafs;
+static bool is_amd;
+static bool show_details;
+static bool show_raw;
+static bool show_flags_only = true;
+static u32 user_index = 0xFFFFFFFF;
+static u32 user_sub = 0xFFFFFFFF;
+static int flines;
+
+static inline void cpuid(u32 *eax, u32 *ebx, u32 *ecx, u32 *edx)
+{
+ /* ecx is often an input as well as an output. */
+ asm volatile("cpuid"
+ : "=a" (*eax),
+ "=b" (*ebx),
+ "=c" (*ecx),
+ "=d" (*edx)
+ : "0" (*eax), "2" (*ecx));
+}
+
+static inline bool has_subleafs(u32 f)
+{
+ if (f == 0x7 || f == 0xd)
+ return true;
+
+ if (is_amd) {
+ if (f == 0x8000001d)
+ return true;
+ return false;
+ }
+
+ switch (f) {
+ case 0x4:
+ case 0xb:
+ case 0xf:
+ case 0x10:
+ case 0x14:
+ case 0x18:
+ case 0x1f:
+ return true;
+ default:
+ return false;
+ }
+}
+
+static void leaf_print_raw(struct subleaf *leaf)
+{
+ if (has_subleafs(leaf->index)) {
+ if (leaf->sub == 0)
+ printf("0x%08x: subleafs:\n", leaf->index);
+
+ printf(" %2d: EAX=0x%08x, EBX=0x%08x, ECX=0x%08x, EDX=0x%08x\n",
+ leaf->sub, leaf->eax, leaf->ebx, leaf->ecx, leaf->edx);
+ } else {
+ printf("0x%08x: EAX=0x%08x, EBX=0x%08x, ECX=0x%08x, EDX=0x%08x\n",
+ leaf->index, leaf->eax, leaf->ebx, leaf->ecx, leaf->edx);
+ }
+}
+
+/* Return true is the input eax/ebx/ecx/edx are all zero */
+static bool cpuid_store(struct cpuid_range *range, u32 f, int subleaf,
+ u32 a, u32 b, u32 c, u32 d)
+{
+ struct cpuid_func *func;
+ struct subleaf *leaf;
+ int s = 0;
+
+ if (a == 0 && b == 0 && c == 0 && d == 0)
+ return true;
+
+ /*
+ * Cut off vendor-prefix from CPUID function as we're using it as an
+ * index into ->funcs.
+ */
+ func = &range->funcs[f & 0xffff];
+
+ if (!func->leafs) {
+ func->leafs = malloc(sizeof(struct subleaf));
+ if (!func->leafs)
+ perror("malloc func leaf");
+
+ func->nr = 1;
+ } else {
+ s = func->nr;
+ func->leafs = realloc(func->leafs, (s + 1) * sizeof(*leaf));
+ if (!func->leafs)
+ perror("realloc f->leafs");
+
+ func->nr++;
+ }
+
+ leaf = &func->leafs[s];
+
+ leaf->index = f;
+ leaf->sub = subleaf;
+ leaf->eax = a;
+ leaf->ebx = b;
+ leaf->ecx = c;
+ leaf->edx = d;
+
+ return false;
+}
+
+static void raw_dump_range(struct cpuid_range *range)
+{
+ u32 f;
+ int i;
+
+ printf("%s Leafs :\n", range->is_ext ? "Extended" : "Basic");
+ printf("================\n");
+
+ for (f = 0; (int)f < range->nr; f++) {
+ struct cpuid_func *func = &range->funcs[f];
+ u32 index = f;
+
+ if (range->is_ext)
+ index += 0x80000000;
+
+ /* Skip leaf without valid items */
+ if (!func->nr)
+ continue;
+
+ /* First item is the main leaf, followed by all subleafs */
+ for (i = 0; i < func->nr; i++)
+ leaf_print_raw(&func->leafs[i]);
+ }
+}
+
+#define MAX_SUBLEAF_NUM 32
+struct cpuid_range *setup_cpuid_range(u32 input_eax)
+{
+ u32 max_func, idx_func;
+ int subleaf;
+ struct cpuid_range *range;
+ u32 eax, ebx, ecx, edx;
+ u32 f = input_eax;
+ int max_subleaf;
+ bool allzero;
+
+ eax = input_eax;
+ ebx = ecx = edx = 0;
+
+ cpuid(&eax, &ebx, &ecx, &edx);
+ max_func = eax;
+ idx_func = (max_func & 0xffff) + 1;
+
+ range = malloc(sizeof(struct cpuid_range));
+ if (!range)
+ perror("malloc range");
+
+ if (input_eax & 0x80000000)
+ range->is_ext = true;
+ else
+ range->is_ext = false;
+
+ range->funcs = malloc(sizeof(struct cpuid_func) * idx_func);
+ if (!range->funcs)
+ perror("malloc range->funcs");
+
+ range->nr = idx_func;
+ memset(range->funcs, 0, sizeof(struct cpuid_func) * idx_func);
+
+ for (; f <= max_func; f++) {
+ eax = f;
+ subleaf = ecx = 0;
+
+ cpuid(&eax, &ebx, &ecx, &edx);
+ allzero = cpuid_store(range, f, subleaf, eax, ebx, ecx, edx);
+ if (allzero)
+ continue;
+ num_leafs++;
+
+ if (!has_subleafs(f))
+ continue;
+
+ max_subleaf = MAX_SUBLEAF_NUM;
+
+ /*
+ * Some can provide the exact number of subleafs,
+ * others have to be tried (0xf)
+ */
+ if (f == 0x7 || f == 0x14 || f == 0x17 || f == 0x18)
+ max_subleaf = (eax & 0xff) + 1;
+
+ if (f == 0xb)
+ max_subleaf = 2;
+
+ for (subleaf = 1; subleaf < max_subleaf; subleaf++) {
+ eax = f;
+ ecx = subleaf;
+
+ cpuid(&eax, &ebx, &ecx, &edx);
+ allzero = cpuid_store(range, f, subleaf,
+ eax, ebx, ecx, edx);
+ if (allzero)
+ continue;
+ num_leafs++;
+ }
+
+ }
+
+ return range;
+}
+
+/*
+ * The basic row format for cpuid.csv is
+ * LEAF,SUBLEAF,register_name,bits,short name,long description
+ *
+ * like:
+ * 0, 0, EAX, 31:0, max_basic_leafs, Max input value for supported subleafs
+ * 1, 0, ECX, 0, sse3, Streaming SIMD Extensions 3(SSE3)
+ */
+static int parse_line(char *line)
+{
+ char *str;
+ int i;
+ struct cpuid_range *range;
+ struct cpuid_func *func;
+ struct subleaf *leaf;
+ u32 index;
+ u32 sub;
+ char buffer[512];
+ char *buf;
+ /*
+ * Tokens:
+ * 1. leaf
+ * 2. subleaf
+ * 3. register
+ * 4. bits
+ * 5. short name
+ * 6. long detail
+ */
+ char *tokens[6];
+ struct reg_desc *reg;
+ struct bits_desc *bdesc;
+ int reg_index;
+ char *start, *end;
+
+ /* Skip comments and NULL line */
+ if (line[0] == '#' || line[0] == '\n')
+ return 0;
+
+ strncpy(buffer, line, 511);
+ buffer[511] = 0;
+ str = buffer;
+ for (i = 0; i < 5; i++) {
+ tokens[i] = strtok(str, ",");
+ if (!tokens[i])
+ goto err_exit;
+ str = NULL;
+ }
+ tokens[5] = strtok(str, "\n");
+ if (!tokens[5])
+ goto err_exit;
+
+ /* index/main-leaf */
+ index = strtoull(tokens[0], NULL, 0);
+
+ if (index & 0x80000000)
+ range = leafs_ext;
+ else
+ range = leafs_basic;
+
+ index &= 0x7FFFFFFF;
+ /* Skip line parsing for non-existing indexes */
+ if ((int)index >= range->nr)
+ return -1;
+
+ func = &range->funcs[index];
+
+ /* Return if the index has no valid item on this platform */
+ if (!func->nr)
+ return 0;
+
+ /* subleaf */
+ sub = strtoul(tokens[1], NULL, 0);
+ if ((int)sub > func->nr)
+ return -1;
+
+ leaf = &func->leafs[sub];
+ buf = tokens[2];
+
+ if (strcasestr(buf, "EAX"))
+ reg_index = R_EAX;
+ else if (strcasestr(buf, "EBX"))
+ reg_index = R_EBX;
+ else if (strcasestr(buf, "ECX"))
+ reg_index = R_ECX;
+ else if (strcasestr(buf, "EDX"))
+ reg_index = R_EDX;
+ else
+ goto err_exit;
+
+ reg = &leaf->info[reg_index];
+ bdesc = &reg->descs[reg->nr++];
+
+ /* bit flag or bits field */
+ buf = tokens[3];
+
+ end = strtok(buf, ":");
+ bdesc->end = strtoul(end, NULL, 0);
+ bdesc->start = bdesc->end;
+
+ /* start != NULL means it is bit fields */
+ start = strtok(NULL, ":");
+ if (start)
+ bdesc->start = strtoul(start, NULL, 0);
+
+ strcpy(bdesc->simp, tokens[4]);
+ strcpy(bdesc->detail, tokens[5]);
+ return 0;
+
+err_exit:
+ printf("Warning: wrong line format:\n");
+ printf("\tline[%d]: %s\n", flines, line);
+ return -1;
+}
+
+/* Parse csv file, and construct the array of all leafs and subleafs */
+static void parse_text(void)
+{
+ FILE *file;
+ char *filename, *line = NULL;
+ size_t len = 0;
+ int ret;
+
+ if (show_raw)
+ return;
+
+ filename = user_csv ? user_csv : def_csv;
+ file = fopen(filename, "r");
+ if (!file) {
+ /* Fallback to a csv in the same dir */
+ file = fopen("./cpuid.csv", "r");
+ }
+
+ if (!file) {
+ printf("Fail to open '%s'\n", filename);
+ return;
+ }
+
+ while (1) {
+ ret = getline(&line, &len, file);
+ flines++;
+ if (ret > 0)
+ parse_line(line);
+
+ if (feof(file))
+ break;
+ }
+
+ fclose(file);
+}
+
+
+/* Decode every eax/ebx/ecx/edx */
+static void decode_bits(u32 value, struct reg_desc *rdesc)
+{
+ struct bits_desc *bdesc;
+ int start, end, i;
+ u32 mask;
+
+ for (i = 0; i < rdesc->nr; i++) {
+ bdesc = &rdesc->descs[i];
+
+ start = bdesc->start;
+ end = bdesc->end;
+ if (start == end) {
+ /* single bit flag */
+ if (value & (1 << start))
+ printf("\t%-20s %s%s\n",
+ bdesc->simp,
+ show_details ? "-" : "",
+ show_details ? bdesc->detail : ""
+ );
+ } else {
+ /* bit fields */
+ if (show_flags_only)
+ continue;
+
+ mask = ((u64)1 << (end - start + 1)) - 1;
+ printf("\t%-20s\t: 0x%-8x\t%s%s\n",
+ bdesc->simp,
+ (value >> start) & mask,
+ show_details ? "-" : "",
+ show_details ? bdesc->detail : ""
+ );
+ }
+ }
+}
+
+static void show_leaf(struct subleaf *leaf)
+{
+ if (!leaf)
+ return;
+
+ if (show_raw)
+ leaf_print_raw(leaf);
+
+ decode_bits(leaf->eax, &leaf->info[R_EAX]);
+ decode_bits(leaf->ebx, &leaf->info[R_EBX]);
+ decode_bits(leaf->ecx, &leaf->info[R_ECX]);
+ decode_bits(leaf->edx, &leaf->info[R_EDX]);
+}
+
+static void show_func(struct cpuid_func *func)
+{
+ int i;
+
+ if (!func)
+ return;
+
+ for (i = 0; i < func->nr; i++)
+ show_leaf(&func->leafs[i]);
+}
+
+static void show_range(struct cpuid_range *range)
+{
+ int i;
+
+ for (i = 0; i < range->nr; i++)
+ show_func(&range->funcs[i]);
+}
+
+static inline struct cpuid_func *index_to_func(u32 index)
+{
+ struct cpuid_range *range;
+
+ range = (index & 0x80000000) ? leafs_ext : leafs_basic;
+ index &= 0x7FFFFFFF;
+
+ if (((index & 0xFFFF) + 1) > (u32)range->nr) {
+ printf("ERR: invalid input index (0x%x)\n", index);
+ return NULL;
+ }
+ return &range->funcs[index];
+}
+
+static void show_info(void)
+{
+ struct cpuid_func *func;
+
+ if (show_raw) {
+ /* Show all of the raw output of 'cpuid' instr */
+ raw_dump_range(leafs_basic);
+ raw_dump_range(leafs_ext);
+ return;
+ }
+
+ if (user_index != 0xFFFFFFFF) {
+ /* Only show specific leaf/subleaf info */
+ func = index_to_func(user_index);
+ if (!func)
+ return;
+
+ /* Dump the raw data also */
+ show_raw = true;
+
+ if (user_sub != 0xFFFFFFFF) {
+ if (user_sub + 1 <= (u32)func->nr) {
+ show_leaf(&func->leafs[user_sub]);
+ return;
+ }
+
+ printf("ERR: invalid input subleaf (0x%x)\n", user_sub);
+ }
+
+ show_func(func);
+ return;
+ }
+
+ printf("CPU features:\n=============\n\n");
+ show_range(leafs_basic);
+ show_range(leafs_ext);
+}
+
+static void setup_platform_cpuid(void)
+{
+ u32 eax, ebx, ecx, edx;
+
+ /* Check vendor */
+ eax = ebx = ecx = edx = 0;
+ cpuid(&eax, &ebx, &ecx, &edx);
+
+ /* "htuA" */
+ if (ebx == 0x68747541)
+ is_amd = true;
+
+ /* Setup leafs for the basic and extended range */
+ leafs_basic = setup_cpuid_range(0x0);
+ leafs_ext = setup_cpuid_range(0x80000000);
+}
+
+static void usage(void)
+{
+ printf("kcpuid [-abdfhr] [-l leaf] [-s subleaf]\n"
+ "\t-a|--all Show both bit flags and complex bit fields info\n"
+ "\t-b|--bitflags Show boolean flags only\n"
+ "\t-d|--detail Show details of the flag/fields (default)\n"
+ "\t-f|--flags Specify the cpuid csv file\n"
+ "\t-h|--help Show usage info\n"
+ "\t-l|--leaf=index Specify the leaf you want to check\n"
+ "\t-r|--raw Show raw cpuid data\n"
+ "\t-s|--subleaf=sub Specify the subleaf you want to check\n"
+ );
+}
+
+static struct option opts[] = {
+ { "all", no_argument, NULL, 'a' }, /* show both bit flags and fields */
+ { "bitflags", no_argument, NULL, 'b' }, /* only show bit flags, default on */
+ { "detail", no_argument, NULL, 'd' }, /* show detail descriptions */
+ { "file", required_argument, NULL, 'f' }, /* use user's cpuid file */
+ { "help", no_argument, NULL, 'h'}, /* show usage */
+ { "leaf", required_argument, NULL, 'l'}, /* only check a specific leaf */
+ { "raw", no_argument, NULL, 'r'}, /* show raw CPUID leaf data */
+ { "subleaf", required_argument, NULL, 's'}, /* check a specific subleaf */
+ { NULL, 0, NULL, 0 }
+};
+
+static int parse_options(int argc, char *argv[])
+{
+ int c;
+
+ while ((c = getopt_long(argc, argv, "abdf:hl:rs:",
+ opts, NULL)) != -1)
+ switch (c) {
+ case 'a':
+ show_flags_only = false;
+ break;
+ case 'b':
+ show_flags_only = true;
+ break;
+ case 'd':
+ show_details = true;
+ break;
+ case 'f':
+ user_csv = optarg;
+ break;
+ case 'h':
+ usage();
+ exit(1);
+ break;
+ case 'l':
+ /* main leaf */
+ user_index = strtoul(optarg, NULL, 0);
+ break;
+ case 'r':
+ show_raw = true;
+ break;
+ case 's':
+ /* subleaf */
+ user_sub = strtoul(optarg, NULL, 0);
+ break;
+ default:
+ printf("%s: Invalid option '%c'\n", argv[0], optopt);
+ return -1;
+ }
+
+ return 0;
+}
+
+/*
+ * Do 4 things in turn:
+ * 1. Parse user options
+ * 2. Parse and store all the CPUID leaf data supported on this platform
+ * 2. Parse the csv file, while skipping leafs which are not available
+ * on this platform
+ * 3. Print leafs info based on user options
+ */
+int main(int argc, char *argv[])
+{
+ if (parse_options(argc, argv))
+ return -1;
+
+ /* Setup the cpuid leafs of current platform */
+ setup_platform_cpuid();
+
+ /* Read and parse the 'cpuid.csv' */
+ parse_text();
+
+ show_info();
+ return 0;
+}