smbios: Allow writing to the coreboot version string
When U-Boot is booted from coreboot the SMBIOS tables are written by
coreboot, not U-Boot. The existing method of updating the BIOS version
string does not work in that case, since gd->smbios_version is only set
when U-Boot writes the tables.
Add a new function which allows the version to be updated by parsing the
tables and writing the string in the correct place. Since coreboot
provides a pointer to the SMBIOS tables in its sysinfo structure, this
makes it easy to do the update.
Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/lib/smbios-parser.c b/lib/smbios-parser.c
index b89f988..34203f9 100644
--- a/lib/smbios-parser.c
+++ b/lib/smbios-parser.c
@@ -3,6 +3,8 @@
* Copyright (C) 2020, Bachmann electronic GmbH
*/
+#define LOG_CATEGORY LOGC_BOOT
+
#include <common.h>
#include <smbios.h>
@@ -94,3 +96,39 @@
return string_from_smbios_table(header, index);
}
+
+int smbios_update_version_full(void *smbios_tab, const char *version)
+{
+ const struct smbios_header *hdr;
+ struct smbios_type0 *bios;
+ uint old_len, len;
+ char *ptr;
+
+ log_info("Updating SMBIOS table at %p\n", smbios_tab);
+ hdr = smbios_header(smbios_tab, SMBIOS_BIOS_INFORMATION);
+ if (!hdr)
+ return log_msg_ret("tab", -ENOENT);
+ bios = (struct smbios_type0 *)hdr;
+ ptr = (char *)smbios_string(hdr, bios->bios_ver);
+ if (!ptr)
+ return log_msg_ret("str", -ENOMEDIUM);
+
+ /*
+ * This string is supposed to have at least enough bytes and is
+ * padded with spaces. Update it, taking care not to move the
+ * \0 terminator, so that other strings in the string table
+ * are not disturbed. See smbios_add_string()
+ */
+ old_len = strnlen(ptr, SMBIOS_STR_MAX);
+ len = strnlen(version, SMBIOS_STR_MAX);
+ if (len > old_len)
+ return log_ret(-ENOSPC);
+
+ log_debug("Replacing SMBIOS type 0 version string '%s'\n", ptr);
+ memcpy(ptr, version, len);
+#ifdef LOG_DEBUG
+ print_buffer((ulong)ptr, ptr, 1, old_len + 1, 0);
+#endif
+
+ return 0;
+}