[U-Boot] [PATCH v3 1/6] x86: baytrail: Add fsp-header verification for secure boot FSP

Anatolij Gustschin
2017-11-17T01:13:05Z

From: Markus Valentin <mv@denx.de>

Introduce a new Kconfig variable for secure boot on Bay Trail based
platforms. If this variable is set, the build process tries to use
fsp-sb.bin instead of fsp.bin (-sb is the secure boot enabled FSP).

Also check the two FSP headers against each other and print if secure
boot is enabled or not.

Signed-off-by: Markus Valentin <mv@denx.de>
Signed-off-by: Anatolij Gustschin <agust@denx.de>
---
Changes in v3:
- move BAYTRAIL_SECURE_BOOT to arch/x86/cpu/baytrail/Kconfig
- Kconfig help text improvements
- fix crownbay build breakage

Changes in v2:
- use if (IS_ENABLED(CONFIG_*)) instead of #ifdef
- s/SB/Secure Boot/
- minor Kconfig help cleanup

arch/x86/Kconfig | 3 ++-
arch/x86/cpu/baytrail/Kconfig | 10 ++++++++++
arch/x86/include/asm/fsp/fsp_support.h | 2 ++
arch/x86/lib/fsp/fsp_support.c | 24 ++++++++++++++++++++++++
4 files changed, 38 insertions(+), 1 deletion(-)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 98c56ad7dc..6755e92748 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -350,7 +350,8 @@ config HAVE_FSP
config FSP_FILE
string "Firmware Support Package binary filename"
depends on HAVE_FSP
- default "fsp.bin"
+ default "fsp.bin" if !BAYTRAIL_SECURE_BOOT
+ default "fsp-sb.bin" if BAYTRAIL_SECURE_BOOT
help
The filename of the file to use as Firmware Support Package binary
in the board directory.
diff --git a/arch/x86/cpu/baytrail/Kconfig b/arch/x86/cpu/baytrail/Kconfig
index 1d876b1927..ff244fcd68 100644
--- a/arch/x86/cpu/baytrail/Kconfig
+++ b/arch/x86/cpu/baytrail/Kconfig
@@ -39,4 +39,14 @@ config DEBUG_UART
bool
select DEBUG_UART_BOARD_INIT

+config BAYTRAIL_SECURE_BOOT
+ bool "Enable Secure Boot on Bay Trail"
+ depends on HAVE_FSP
+ default n
+ help
+ Use the secure boot feature of the Bay Trail platform. This switch
+ enables the usage of the secure-boot enabled fsp.bin (fsp-sb.bin).
+ For your board you need to provide this yourself. You can reconfigure
+ your FSP with the Intel BCT tool to enable secure boot.
+
endif
diff --git a/arch/x86/include/asm/fsp/fsp_support.h b/arch/x86/include/asm/fsp/fsp_support.h
index df3add008c..124a4148a0 100644
--- a/arch/x86/include/asm/fsp/fsp_support.h
+++ b/arch/x86/include/asm/fsp/fsp_support.h
@@ -22,6 +22,8 @@
#define FSP_LOWMEM_BASE 0x100000UL
#define FSP_HIGHMEM_BASE 0x100000000ULL
#define UPD_TERMINATOR 0x55AA
+#define FSP_FIRST_HEADER_OFFSET 0x94
+#define FSP_SECOND_HEADER_OFFSET 0x20494

/**
diff --git a/arch/x86/lib/fsp/fsp_support.c b/arch/x86/lib/fsp/fsp_support.c
index e0c49be635..d79a6e900a 100644
--- a/arch/x86/lib/fsp/fsp_support.c
+++ b/arch/x86/lib/fsp/fsp_support.c
@@ -97,6 +97,8 @@ void fsp_continue(u32 status, void *hob_list)
fsp_init_done(hob_list);
}

+#define SB_PRFX "Secure Boot:"
+
void fsp_init(u32 stack_top, u32 boot_mode, void *nvs_buf)
{
struct fsp_config_data config_data;
@@ -116,6 +118,14 @@ void fsp_init(u32 stack_top, u32 boot_mode, void *nvs_buf)
panic("Invalid FSP header");
}

+ if (IS_ENABLED(CONFIG_BAYTRAIL_SECURE_BOOT)) {
+ /* Compare primary and secondary header */
+ if (memcmp((void *)(CONFIG_FSP_ADDR + FSP_FIRST_HEADER_OFFSET),
+ (void *)(CONFIG_FSP_ADDR + FSP_SECOND_HEADER_OFFSET),
+ fsp_hdr->hdr_len))
+ panic("%s 1st & 2nd FSP headers don't match", SB_PRFX);
+ }
+
config_data.common.fsp_hdr = fsp_hdr;
config_data.common.stack_top = stack_top;
config_data.common.boot_mode = boot_mode;
@@ -130,6 +140,20 @@ void fsp_init(u32 stack_top, u32 boot_mode, void *nvs_buf)

fsp_upd = &config_data.fsp_upd;

+ /*
+ * On some platforms there is no 'enable_secure_boot' field
+ * in VPD region struct, so we have to use ifdef here.
+ */
+ #ifdef CONFIG_BAYTRAIL_SECURE_BOOT
+ /*
+ * If the enable secure boot flag is not 1, secure boot has not
+ * been activated in the FSP which results in the TXE-Engine not
+ * getting loaded
+ */
+ printf("FSP: Secure Boot %sabled\n",
+ fsp_vpd->enable_secure_boot == 1 ? "en" : "dis");
+ #endif
+
/* Copy default data from Flash */
memcpy(fsp_upd, (void *)(fsp_hdr->img_base + fsp_vpd->upd_offset),
sizeof(struct upd_region));
--
2.11.0