[U-Boot] [PATCH v2 2/3] x86: baytrail: Add fsp-header verification for secure boot fsp

[Anatolij Gustschin <agust@denx.de>]

From: Markus Valentin <mv@denx.de>

Introduce a new Kconfig variable for secure boot on baytrail 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 v2:
 - use if (IS_ENABLED(CONFIG_*)) instead of #ifdef
 - s/SB/Secure Boot/
 - minor Kconfig help cleanup

 arch/x86/Kconfig                       | 13 ++++++++++++-
 arch/x86/include/asm/fsp/fsp_support.h |  2 ++
 arch/x86/lib/fsp/fsp_support.c         | 18 ++++++++++++++++++
 3 files changed, 32 insertions(+), 1 deletion(-)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 9ead3eb..8cea393 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -348,7 +348,8 @@ 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.
@@ -400,6 +401,16 @@ config FSP_BROKEN_HOB
 	  do not overwrite the important boot service data which is used by
 	  FSP, otherwise the subsequent call to fsp_notify() will fail.
 
+config BAYTRAIL_SECURE_BOOT
+	bool "Enable Secure Boot on BayTrail"
+	depends on HAVE_FSP
+	default n
+	help
+	  Use the SecureBoot Features of the BayTrail 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 SecureBoot.
+
 config ENABLE_MRC_CACHE
 	bool "Enable MRC cache"
 	depends on !EFI && !SYS_COREBOOT
diff --git a/arch/x86/include/asm/fsp/fsp_support.h b/arch/x86/include/asm/fsp/fsp_support.h
index 61d811f..bae17bc 100644
--- a/arch/x86/include/asm/fsp/fsp_support.h
+++ b/arch/x86/include/asm/fsp/fsp_support.h
@@ -21,6 +21,8 @@
 #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 a480361..0bbd9ae 100644
--- a/arch/x86/lib/fsp/fsp_support.c
+++ b/arch/x86/lib/fsp/fsp_support.c
@@ -120,6 +120,14 @@ 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("Secure Boot: 1st & 2nd FSP headers don't match");
+	}
+
 	config_data.common.fsp_hdr = fsp_hdr;
 	config_data.common.stack_top = stack_top;
 	config_data.common.boot_mode = boot_mode;
@@ -134,6 +142,16 @@ void fsp_init(u32 stack_top, u32 boot_mode, void *nvs_buf)
 
 	fsp_upd = &config_data.fsp_upd;
 
+	if (IS_ENABLED(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");
+	}
+
 	/* Copy default data from Flash */
 	memcpy(fsp_upd, (void *)(fsp_hdr->img_base + fsp_vpd->upd_offset),
 	       sizeof(struct upd_region));
-- 
2.7.4