arch/x86/smbios.c: Allow creating entries for empty DIMM slots
Properly handle meminfo DIMMs with `dimm_size` of 0, which represent
empty slots. This allows platform code to create dummy meminfo DIMMs
so that SMBIOS tables have type 17 entries for empty DIMM slots.
Change-Id: I17ae83edf94483bd2eeef5524ff82721c196b8ba
Signed-off-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/64035
Reviewed-by: Jonathan Zhang <jonzhang@fb.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
diff --git a/src/arch/x86/smbios.c b/src/arch/x86/smbios.c
index 5b8df5bc..8d9de7c 100644
--- a/src/arch/x86/smbios.c
+++ b/src/arch/x86/smbios.c
@@ -277,6 +277,26 @@
return smbios_full_table_len(&t->header, t->eos);
}
+static int create_smbios_type17_for_empty_slot(struct dimm_info *dimm,
+ unsigned long *current, int *handle,
+ int type16_handle)
+{
+ struct smbios_type17 *t = smbios_carve_table(*current, SMBIOS_MEMORY_DEVICE,
+ sizeof(*t), *handle);
+ t->phys_memory_array_handle = type16_handle;
+ /* no handle for error information */
+ t->memory_error_information_handle = 0xfffe;
+ t->total_width = 0xffff; /* Unknown */
+ t->data_width = 0xffff; /* Unknown */
+ t->form_factor = 0x2; /* Unknown */
+ smbios_fill_dimm_locator(dimm, t); /* Device and Bank */
+ t->memory_type = 0x2; /* Unknown */
+ t->type_detail = 0x2; /* Unknown */
+
+ *handle += 1;
+ return smbios_full_table_len(&t->header, t->eos);
+}
+
#define VERSION_VPD "firmware_version"
static const char *vpd_get_bios_version(void)
{
@@ -947,15 +967,19 @@
printk(BIOS_INFO, "Create SMBIOS type 17\n");
for (i = 0; i < meminfo->dimm_cnt && i < ARRAY_SIZE(meminfo->dimm); i++) {
- struct dimm_info *dimm;
- dimm = &meminfo->dimm[i];
+ struct dimm_info *d = &meminfo->dimm[i];
/*
* Windows 10 GetPhysicallyInstalledSystemMemory functions reads SMBIOS tables
* type 16 and type 17. The type 17 tables need to point to a type 16 table.
* Otherwise, the physical installed memory size is guessed from the system
* memory map, which results in a slightly smaller value than the actual size.
*/
- const int len = create_smbios_type17_for_dimm(dimm, current, handle, type16);
+ int len;
+ if (d->dimm_size > 0)
+ len = create_smbios_type17_for_dimm(d, current, handle, type16);
+ else
+ len = create_smbios_type17_for_empty_slot(d, current, handle, type16);
+
*current += len;
totallen += len;
}
@@ -1046,6 +1070,9 @@
for (i = 0; i < meminfo->dimm_cnt && i < ARRAY_SIZE(meminfo->dimm); i++) {
struct dimm_info *dimm;
dimm = &meminfo->dimm[i];
+ if (dimm->dimm_size == 0)
+ continue;
+
u32 end_addr = start_addr + (dimm->dimm_size << 10) - 1;
totallen += smbios_write_type20_table(current, handle, start_addr, end_addr,
type17_handle, type19_handle);