[v0.81][ARM][Refactoring] Refactoring and very basic ARM support

src/common/udev.c

@@ -10,8 +10,8 @@
 #ifdef ARCH_X86
   #include "../x86/cpuid.h"
 #else
-  #include "../arm/cpuid.h"
-#endif  
+  #include "../arm/midr.h"
+#endif
 
 #define _PATH_SYS_SYSTEM    "/sys/devices/system"
 #define _PATH_SYS_CPU       _PATH_SYS_SYSTEM"/cpu"
@@ -77,3 +77,145 @@ long get_max_freq_from_file() {
 long get_min_freq_from_file() {
   return get_freq_from_file(_PATH_FREQUENCY_MIN);
 }
+
+#ifdef ARCH_ARM
+
+#define UNKNOWN -1
+#define _PATH_CPUINFO "/proc/cpuinfo"
+
+#define CPUINFO_CPU_IMPLEMENTER_STR  "CPU implementer\t: "
+#define CPUINFO_CPU_ARCHITECTURE_STR "CPU architecture: "
+#define CPUINFO_CPU_VARIANT_STR      "CPU variant\t: "
+#define CPUINFO_CPU_PART_STR         "CPU part\t: "
+#define CPUINFO_CPU_REVISION_STR     "CPU revision\t: "
+
+#define CPUINFO_CPU_STRING "processor"
+
+int get_ncores_from_cpuinfo() {
+  int fd = open(_PATH_CPUINFO, O_RDONLY);
+
+  if(fd == -1) {
+    perror("open");
+    return UNKNOWN;
+  }
+
+  //File exists, read it
+  int bytes_read = 0;
+  int offset = 0;
+  int block = 128;
+  char* buf = malloc(sizeof(char)*DEFAULT_FILE_SIZE);
+  memset(buf, 0, sizeof(char)*DEFAULT_FILE_SIZE);
+
+  while (  (bytes_read = read(fd, buf+offset, block)) > 0 ) {
+    offset += bytes_read;
+  }
+
+  int ncores = 0;
+  char* tmp = buf;
+  do {
+    tmp++;
+    ncores++;
+    tmp = strstr(tmp, CPUINFO_CPU_STRING);
+  } while(tmp != NULL);
+
+  free(buf);
+
+  if (close(fd) == -1) {
+    perror("close");
+  }
+
+  return ncores;
+}
+
+long parse_cpuinfo_field(char* buf, char* field_str, int field_base) {
+  char* tmp = strstr(buf, field_str);
+  if(tmp == NULL) return -1;
+  tmp += strlen(field_str);
+
+  char* end;
+  errno = 0;
+  long ret = strtol(tmp, &end, field_base);
+  if(errno != 0) {
+    perror("strtol");
+    return -1;
+  }
+
+  return ret;
+}
+// https://developer.arm.com/docs/ddi0595/h/aarch32-system-registers/midr
+// https://static.docs.arm.com/ddi0595/h/SysReg_xml_v86A-2020-06.pdf
+uint32_t get_midr_from_cpuinfo(uint32_t core) {
+  int fd = open(_PATH_CPUINFO, O_RDONLY);
+
+  if(fd == -1) {
+    perror("open");
+    return UNKNOWN;
+  }
+
+  //File exists, read it
+  int bytes_read = 0;
+  int offset = 0;
+  int block = 128;
+  char* buf = malloc(sizeof(char)*DEFAULT_FILE_SIZE);
+  memset(buf, 0, sizeof(char)*DEFAULT_FILE_SIZE);
+
+  while (  (bytes_read = read(fd, buf+offset, block)) > 0 ) {
+    offset += bytes_read;
+  }
+
+  char* tmp = buf;
+  uint32_t current_core = 0;
+  while(core != current_core && tmp != NULL) {
+    tmp++;
+    current_core++;
+    tmp = strstr(tmp, CPUINFO_CPU_STRING);
+  }
+
+  uint32_t cpu_implementer;
+  uint32_t cpu_architecture;
+  uint32_t cpu_variant;
+  uint32_t cpu_part;
+  uint32_t cpu_revision;
+  uint32_t midr = 0;
+  long ret;
+
+  if ((ret = parse_cpuinfo_field(tmp, CPUINFO_CPU_IMPLEMENTER_STR, 16)) < 0) {
+    printf("Failed parsing cpu_implementer\n");
+    return 0;
+  }
+  cpu_implementer = (uint32_t) ret;
+
+  if ((ret = parse_cpuinfo_field(tmp, CPUINFO_CPU_ARCHITECTURE_STR, 10)) < 0) {
+    printf("Failed parsing cpu_architecture\n");
+    return 0;
+  }
+  cpu_architecture = (uint32_t) 0xF; // Why?
+
+  if ((ret = parse_cpuinfo_field(tmp, CPUINFO_CPU_VARIANT_STR, 16)) < 0) {
+    printf("Failed parsing cpu_variant\n");
+    return 0;
+  }
+  cpu_variant = (uint32_t) ret;
+
+  if ((ret = parse_cpuinfo_field(tmp, CPUINFO_CPU_PART_STR, 16)) < 0) {
+    printf("Failed parsing cpu_part\n");
+    return 0;
+  }
+  cpu_part = (uint32_t) ret;
+
+  if ((ret = parse_cpuinfo_field(tmp, CPUINFO_CPU_REVISION_STR, 10)) < 0) {
+    printf("Failed parsing cpu_revision\n");
+    return 0;
+  }
+  cpu_revision = (uint32_t) ret;
+
+  midr = midr_set_implementer(midr, cpu_implementer);
+  midr = midr_set_variant(midr, cpu_variant);
+  midr = midr_set_architecture(midr, cpu_architecture);
+  midr = midr_set_part(midr, cpu_part);
+  midr = midr_set_revision(midr, cpu_revision);
+
+  return midr;
+}
+
+#endif /* ARCH_ARM */