x86: Ensure IDT and GDT remain 16-byte aligned post relocation

Some CPUs have strict alignment requirements for these tables

Signed-off-by: Graeme Russ <graeme.russ@gmail.com>

diff --git a/arch/x86/cpu/interrupts.c b/arch/x86/cpu/interrupts.c
index e007511..e0958eb 100644 (file)
--- a/arch/x86/cpu/interrupts.c
+++ b/arch/x86/cpu/interrupts.c
@@ -174,7 +174,7 @@ struct desc_ptr {
        unsigned short segment;
 } __packed;
 
-struct idt_entry idt[256];
+struct idt_entry idt[256] __attribute__((aligned(16)));
 
 struct desc_ptr idt_ptr;
 

diff --git a/arch/x86/lib/board.c b/arch/x86/lib/board.c
index b445179..244a021 100644 (file)
--- a/arch/x86/lib/board.c
+++ b/arch/x86/lib/board.c
@@ -161,19 +161,26 @@ gd_t *gd;
 
 static int calculate_relocation_address(void)
 {
-       void *text_start = &__text_start;
-       void *bss_end = &__bss_end;
-       void *dest_addr;
+       ulong text_start = (ulong)&__text_start;
+       ulong bss_end = (ulong)&__bss_end;
+       ulong dest_addr;
        ulong rel_offset;
 
        /* Calculate destination RAM Address and relocation offset */
-       dest_addr = (void *)gd->ram_size;
+       dest_addr = gd->ram_size;
        dest_addr -= CONFIG_SYS_STACK_SIZE;
        dest_addr -= (bss_end - text_start);
+
+       /*
+        * Round destination address down to 16-byte boundary to keep
+        * IDT and GDT 16-byte aligned
+        */
+       dest_addr &= ~15;
+
        rel_offset = dest_addr - text_start;
 
        gd->start_addr_sp = gd->ram_size;
-       gd->relocaddr = (ulong)dest_addr;
+       gd->relocaddr = dest_addr;
        gd->reloc_off = rel_offset;
 
        return 0;