On 10/15/23 04:45, Simon Glass wrote:
When the SMBIOS table is written to an address above 4GB a 32-bit table
address is not large enough.
Use an SMBIOS3 table in that case.
Note that we cannot use efi_allocate_pages() since this function has
nothing to do with EFI. There is no equivalent function to allocate
memory below 4GB in U-Boot. One solution would be to create a separate
malloc() pool, or just always put the malloc() pool below 4GB.
Signed-off-by: Simon Glass <s...@chromium.org>
---
Changes in v2:
- Check the end of the table rather than the start.
include/smbios.h | 22 +++++++++++++++++++++-
lib/smbios.c | 24 +++++++++++++++++++-----
2 files changed, 40 insertions(+), 6 deletions(-)
diff --git a/include/smbios.h b/include/smbios.h
index c9df2706f5a6..ddabb558299e 100644
--- a/include/smbios.h
+++ b/include/smbios.h
@@ -12,7 +12,8 @@
/* SMBIOS spec version implemented */
#define SMBIOS_MAJOR_VER 3
-#define SMBIOS_MINOR_VER 0
+#define SMBIOS_MINOR_VER 7
+
enum {
SMBIOS_STR_MAX = 64, /* Maximum length allowed for a string */
@@ -54,6 +55,25 @@ struct __packed smbios_entry {
u8 bcd_rev;
};
+struct __packed smbios3_entry {
+ u8 anchor[5];
+ u8 checksum;
+ u8 length;
+ u8 major_ver;
+
+ u8 minor_ver;
+ u8 docrev;
+ u8 entry_point_rev;
+ u8 reserved;
+ u32 max_struct_size;
+
+ u64 struct_table_address;
+};
+
+/* These two structures should use the same amount of 16-byte-aligned space */
+static_assert(ALIGN(16, sizeof(struct smbios_entry)) ==
+ ALIGN(16, sizeof(struct smbios3_entry)));
+
/* BIOS characteristics */
#define BIOS_CHARACTERISTICS_PCI_SUPPORTED (1 << 7)
#define BIOS_CHARACTERISTICS_UPGRADEABLE (1 << 11)
diff --git a/lib/smbios.c b/lib/smbios.c
index c7a557bc9b7b..92e98388084f 100644
--- a/lib/smbios.c
+++ b/lib/smbios.c
@@ -487,7 +487,11 @@ ulong write_smbios_table(ulong addr)
addr = ALIGN(addr, 16);
start_addr = addr;
- addr += sizeof(struct smbios_entry);
+ /*
+ * So far we don't know which struct will be used, but they both end
+ * up using the same amount of 16-bit-aligned space
+ */
+ addr += max(sizeof(struct smbios_entry), sizeof(struct smbios3_entry));
addr = ALIGN(addr, 16);
tables = addr;
@@ -512,14 +516,24 @@ ulong write_smbios_table(ulong addr)
* sandbox's DRAM buffer.
*/
table_addr = (ulong)map_sysmem(tables, 0);
- if (sizeof(table_addr) > sizeof(u32) && table_addr > (ulong)UINT_MAX) {
+ if (sizeof(table_addr) > sizeof(u32) && addr >= (ulong)UINT_MAX) {
You have to check the end of the the last SMBIOS structure not the start
of the first SMBIOS structure against UINT_MAX.
+ struct smbios3_entry *se;
/*
* We need to put this >32-bit pointer into the table but the
* field is only 32 bits wide.
*/
- printf("WARNING: SMBIOS table_address overflow %llx\n",
- (unsigned long long)table_addr);
- addr = 0;
+ printf("WARNING: Using SMBIOS3.0 due to table-address overflow
%lx\n",
+ table_addr);
This should be log_debug().
+ se = map_sysmem(start_addr, sizeof(struct smbios_entry));
+ memset(se, '\0', sizeof(struct smbios_entry));
+ memcpy(se->anchor, "_SM3_", 5);
+ se->length = sizeof(struct smbios3_entry);
+ se->major_ver = SMBIOS_MAJOR_VER;
+ se->minor_ver = SMBIOS_MINOR_VER;
+ se->docrev = 0;
+ se->entry_point_rev = 1;
+ se->max_struct_size = len;
+ se->struct_table_address = table_addr;
You must fill the checksum:
se->checksum = table_compute_checksum(se, sizeof(struct smbios3_entry));
With the checksum filled I can use dmidecode in Linux based on the
SMBIOS3 table:
ubuntu@ubuntu:~$ sudo dmidecode
# dmidecode 3.5
# SMBIOS3 entry point at 0x27ef53000
Found SMBIOS entry point in EFI, reading table from /dev/mem.
SMBIOS 3.7.0 present.
# SMBIOS implementations newer than version 3.5.0 are not
# fully supported by this version of dmidecode.
Table at 0x27EF53020.
Handle 0x0000, DMI type 0, 24 bytes
BIOS Information
Vendor: U-Boot
...
Best regards
Heinrich
} else {
struct smbios_entry *se;
