From 0864c565a274ddbc23dda667d71524e7efbbef8f Mon Sep 17 00:00:00 2001 From: Simon Glass Date: Wed, 16 May 2018 09:42:19 -0600 Subject: [PATCH] efi: Update some comments related to smbios tables Clarify the operation of this code with some additional comments. Signed-off-by: Simon Glass Reviewed-by: Heinrich Schuchardt Signed-off-by: Alexander Graf --- include/efi_loader.h | 7 +++++++ include/smbios.h | 5 +++-- lib/efi_loader/efi_smbios.c | 7 ++++++- 3 files changed, 16 insertions(+), 3 deletions(-) diff --git a/include/efi_loader.h b/include/efi_loader.h index 0c286bf..c66252a 100644 --- a/include/efi_loader.h +++ b/include/efi_loader.h @@ -214,6 +214,13 @@ efi_status_t efi_net_register(void); /* Called by bootefi to make the watchdog available */ efi_status_t efi_watchdog_register(void); /* Called by bootefi to make SMBIOS tables available */ +/** + * efi_smbios_register() - write out SMBIOS tables + * + * Called by bootefi to make SMBIOS tables available + * + * @return 0 if OK, -ENOMEM if no memory is available for the tables + */ efi_status_t efi_smbios_register(void); struct efi_simple_file_system_protocol * diff --git a/include/smbios.h b/include/smbios.h index 79880ef..97b9ddc 100644 --- a/include/smbios.h +++ b/include/smbios.h @@ -231,8 +231,9 @@ typedef int (*smbios_write_type)(ulong *addr, int handle); * * This writes SMBIOS table at a given address. * - * @addr: start address to write SMBIOS table - * @return: end address of SMBIOS table + * @addr: start address to write SMBIOS table. If this is not + * 16-byte-aligned then it will be aligned before the table is written + * @return: end address of SMBIOS table (and start address for next entry) */ ulong write_smbios_table(ulong addr); diff --git a/lib/efi_loader/efi_smbios.c b/lib/efi_loader/efi_smbios.c index 482436e..7c3fc8a 100644 --- a/lib/efi_loader/efi_smbios.c +++ b/lib/efi_loader/efi_smbios.c @@ -29,7 +29,12 @@ efi_status_t efi_smbios_register(void) if (ret != EFI_SUCCESS) return ret; - /* Generate SMBIOS tables */ + /* + * Generate SMBIOS tables - we know that efi_allocate_pages() returns + * a 4k-aligned address, so it is safe to assume that + * write_smbios_table() will write the table at that address. + */ + assert(!(dmi & 0xf)); write_smbios_table(dmi); /* And expose them to our EFI payload */