src/commonlib/bsd/elog.c

   1 /* SPDX-License-Identifier: BSD-3-Clause */
   2
   3 #include <commonlib/bsd/bcd.h>
   4 #include <commonlib/bsd/elog.h>
   5 #include <stddef.h>
   6
   7 /*
   8  * verify and validate if header is a valid coreboot Event Log header.
   9  * return CB_ERR if invalid, otherwise CB_SUCCESS.
  10  */
  11 enum cb_err elog_verify_header(const struct elog_header *header)
  12 {
  13         if (header == NULL)
  14                 return CB_ERR;
  15
  16         if (header->magic != ELOG_SIGNATURE)
  17                 return CB_ERR;
  18
  19         if (header->version != ELOG_VERSION)
  20                 return CB_ERR;
  21
  22         if (header->header_size != sizeof(*header))
  23                 return CB_ERR;
  24
  25         return CB_SUCCESS;
  26 }
  27
  28 /*
  29  * return the next elog event.
  30  * return NULL if event is invalid.
  31  */
  32 const struct event_header *elog_get_next_event(const struct event_header *event)
  33 {
  34         if (!event)
  35                 return NULL;
  36
  37         /* Point to next event */
  38         return (const struct event_header *)((const void *)(event) + event->length);
  39 }
  40
  41 /* return the data associated to the event_header. */
  42 const void *event_get_data(const struct event_header *event)
  43 {
  44         /*
  45          * Pointing to the next event returns the data, since data is the first
  46          * field right after the header.
  47          */
  48         return (const void *)(&event[1]);
  49 }
  50
  51 /* Populate timestamp in event header with given time. */
  52 void elog_fill_timestamp(struct event_header *event, uint8_t sec, uint8_t min,
  53                          uint8_t hour, uint8_t mday, uint8_t mon, uint16_t year)
  54 {
  55         event->second = bin2bcd(sec);
  56         event->minute = bin2bcd(min);
  57         event->hour = bin2bcd(hour);
  58         event->day = bin2bcd(mday);
  59         event->month = bin2bcd(mon);
  60         event->year = bin2bcd(year % 100);
  61
  62         /* Basic check of expected ranges. */
  63         if (event->month > 0x12 || event->day > 0x31 || event->hour > 0x23 ||
  64             event->minute > 0x59 || event->second > 0x59) {
  65                 event->year   = 0;
  66                 event->month  = 0;
  67                 event->day    = 0;
  68                 event->hour   = 0;
  69                 event->minute = 0;
  70                 event->second = 0;
  71         }
  72 }
  73
  74 void elog_update_checksum(struct event_header *event, uint8_t checksum)
  75 {
  76         uint8_t *event_data = (uint8_t *)event;
  77         event_data[event->length - 1] = checksum;
  78 }
  79
  80 uint8_t elog_checksum_event(const struct event_header *event)
  81 {
  82         uint8_t index, checksum = 0;
  83         const uint8_t *data = (const uint8_t *)event;
  84
  85         for (index = 0; index < event->length; index++)
  86                 checksum += data[index];
  87         return checksum;
  88 }