[smbios] Add support for the 64-bit SMBIOS3 entry point

Support UEFI systems that provide only 64-bit versions of the SMBIOS
entry point.

Signed-off-by: Michael Brown <mcb30@ipxe.org>

2 files changed, 35 insertions, 18 deletions

diff --git a/src/interface/efi/efi_smbios.c b/src/interface/efi/efi_smbios.c
index 304f95a..d7877b0 100644
--- a/src/interface/efi/efi_smbios.c
+++ b/src/interface/efi/efi_smbios.c
@@ -34,6 +34,10 @@ FILE_LICENCE ( GPL2_OR_LATER );
 static struct smbios_entry *smbios_entry;
 EFI_USE_TABLE ( SMBIOS_TABLE, &smbios_entry, 0 );
 
+/** SMBIOS configuration table */
+static struct smbios3_entry *smbios3_entry;
+EFI_USE_TABLE ( SMBIOS3_TABLE, &smbios3_entry, 0 );
+
 /**
  * Find SMBIOS
  *
@@ -42,26 +46,34 @@ EFI_USE_TABLE ( SMBIOS_TABLE, &smbios_entry, 0 );
  */
 static int efi_find_smbios ( struct smbios *smbios ) {
 
-	if ( ! smbios_entry ) {
-		DBG ( "No SMBIOS table provided\n" );
-		return -ENODEV;
+	/* Use 64-bit table if present */
+	if ( smbios3_entry && ( smbios3_entry->signature == SMBIOS3_SIGNATURE ) ) {
+		smbios->address = phys_to_user ( smbios3_entry->smbios_address );
+		smbios->len = smbios3_entry->smbios_len;
+		smbios->count = 0;
+		smbios->version =
+			SMBIOS_VERSION ( smbios3_entry->major, smbios3_entry->minor );
+		DBG ( "Found 64-bit SMBIOS v%d.%d entry point at %p (%lx+%zx)\n",
+		      smbios3_entry->major, smbios3_entry->minor, smbios3_entry,
+		      user_to_phys ( smbios->address, 0 ), smbios->len );
+		return 0;
 	}
 
-	if ( smbios_entry->signature != SMBIOS_SIGNATURE ) {
-		DBG ( "Invalid SMBIOS signature\n" );
-		return -ENODEV;
+	/* Otherwise, use 32-bit table if present */
+	if ( smbios_entry && ( smbios_entry->signature == SMBIOS_SIGNATURE ) ) {
+		smbios->address = phys_to_user ( smbios_entry->smbios_address );
+		smbios->len = smbios_entry->smbios_len;
+		smbios->count = smbios_entry->smbios_count;
+		smbios->version =
+			SMBIOS_VERSION ( smbios_entry->major, smbios_entry->minor );
+		DBG ( "Found 32-bit SMBIOS v%d.%d entry point at %p (%lx+%zx)\n",
+		      smbios_entry->major, smbios_entry->minor, smbios_entry,
+		      user_to_phys ( smbios->address, 0 ), smbios->len );
+		return 0;
 	}
 
-	smbios->address = phys_to_user ( smbios_entry->smbios_address );
-	smbios->len = smbios_entry->smbios_len;
-	smbios->count = smbios_entry->smbios_count;
-	smbios->version =
-		SMBIOS_VERSION ( smbios_entry->major, smbios_entry->minor );
-	DBG ( "Found SMBIOS v%d.%d entry point at %p (%x+%zx)\n",
-	      smbios_entry->major, smbios_entry->minor, smbios_entry,
-	      smbios_entry->smbios_address, smbios->len );
-
-	return 0;
+	DBG ( "No SMBIOS table provided\n" );
+	return -ENODEV;
 }
 
 PROVIDE_SMBIOS ( efi, find_smbios, efi_find_smbios );
diff --git a/src/interface/smbios/smbios.c b/src/interface/smbios/smbios.c
index 1dcf819..5bd76f1 100644
--- a/src/interface/smbios/smbios.c
+++ b/src/interface/smbios/smbios.c
@@ -130,8 +130,8 @@ int find_smbios_structure ( unsigned int type, unsigned int instance,
 	assert ( smbios.address != UNULL );
 
 	/* Scan through list of structures */
-	while ( ( ( offset + sizeof ( structure->header ) ) < smbios.len )
-		&& ( count < smbios.count ) ) {
+	while ( ( ( offset + sizeof ( structure->header ) ) < smbios.len ) &&
+		( ( smbios.count == 0 ) || ( count < smbios.count ) ) ) {
 
 		/* Read next SMBIOS structure header */
 		copy_from_user ( &structure->header, smbios.address, offset,
@@ -157,6 +157,11 @@ int find_smbios_structure ( unsigned int type, unsigned int instance,
 		      "strings length %zx\n", offset, structure->header.type,
 		      structure->header.len, structure->strings_len );
 
+		/* Stop if we have reached an end-of-table marker */
+		if ( ( smbios.count == 0 ) &&
+		     ( structure->header.type == SMBIOS_TYPE_END ) )
+			break;
+
 		/* If this is the structure we want, return */
 		if ( ( structure->header.type == type ) &&
 		     ( instance-- == 0 ) ) {