[coreboot-gerrit] Change in coreboot[master]: program layout: align to 64 bytes when Boot Guard is enabled

[Michał Żygowski (Code Review)]

Michał Żygowski has uploaded this change for review. ( https://review.coreboot.org/c/coreboot/+/43401 )

Change subject: program layout: align to 64 bytes when Boot Guard is enabled
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program layout: align to 64 bytes when Boot Guard is enabled

FIT entries for IBB segmnets have 64 byte granularity. Enforce the
64 bytes alignment on all programs and FIT table to ensure the
entires for IBB will be added correctly.

Signed-off-by: Michał Żygowski 
Change-Id: I3ce09e24d716fe9845104205bc934bd2a0efc9cb
---
M src/arch/x86/memlayout.ld
M src/cpu/intel/fit/fit.S
M src/lib/program.ld
3 files changed, 24 insertions(+), 0 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/01/43401/1

diff --git a/src/arch/x86/memlayout.ld b/src/arch/x86/memlayout.ld
index 3659cc9..605ed24 100644
--- a/src/arch/x86/memlayout.ld
+++ b/src/arch/x86/memlayout.ld
@@ -47,3 +47,8 @@
 #include <cpu/intel/fit/fit.ld>
 #endif
 #endif  /* ENV_BOOTBLOCK */
+
+/* Each program stage needs to be 64 bytes aligned to be added as FIT entry */
+#if CONFIG_INTEL_BOOTGUARD
+. = ALIGN(64);
+#endif
diff --git a/src/cpu/intel/fit/fit.S b/src/cpu/intel/fit/fit.S
index 3b7396c..037918a 100644
--- a/src/cpu/intel/fit/fit.S
+++ b/src/cpu/intel/fit/fit.S
@@ -9,7 +9,15 @@
 .previous

.section .text
+#if CONFIG(INTEL_BOOTGUARD)
+/*
+ * FIT must be excluded from IBB with BootGuard. As the IBB segments have 64
+ * byte granularity, align the FIT to 64 bytes.
+ */
+.align 64
+#else
 .align 16
+#endif
 .global fit_table
 .global fit_table_end
 fit_table:
@@ -28,5 +36,12 @@
 /* Checksum byte - must add to zero. */
 .byte 0x7d
 .fill CONFIG_CPU_INTEL_NUM_FIT_ENTRIES*16
+#if CONFIG(INTEL_BOOTGUARD)
+/*
+ * Just in case the FIT does not end on 64 byte aligned address, maintain the
+ * 64 byte boundaries of IBB segments.
+ */
+.align 64
+#endif
 fit_table_end:
 .previous
diff --git a/src/lib/program.ld b/src/lib/program.ld
index 88a3126..ee105e3 100644
--- a/src/lib/program.ld
+++ b/src/lib/program.ld
@@ -48,6 +48,10 @@
    *(.rodata);
    *(.rodata.*);
    . = ALIGN(ARCH_POINTER_ALIGN_SIZE);
+#if CONFIG_INTEL_BOOTGUARD
+/* Each program stage needs to be 64 bytes aligned to be added as FIT entry */
+	. = ALIGN(64);
+#endif
    _etext = .;
 } : to_load