x86: Add support for passing tables into U-Boot

The EFI stub provides information to U-Boot in a table. This includes the
memory map which is needed to decide where to relocate U-Boot. Collect this
information in the early init code and store it in global_data.

Fix up the BIST code at the same time since we don't have it when booting
from EFI and can assume it is 0.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

arch/x86/cpu/start.S

@@ -42,6 +42,13 @@ _x86boot_start:
 
 	/* Tell 32-bit code it is being entered from an in-RAM copy */
 	movl	$GD_FLG_WARM_BOOT, %ebx
+
+	/*
+	 * Zero the BIST (Built-In Self Test) value since we don't have it.
+	 * It must be 0 or the previous loader would have reported an error.
+	 */
+	movl	$0, %ebp
+
 	jmp	1f
 
 	/* Add a way for tools to discover the _start entry point */
@@ -53,9 +60,13 @@ _start:
 	 * Set %ebx to GD_FLG_COLD_BOOT to indicate this.
 	 */
 	movl	$GD_FLG_COLD_BOOT, %ebx
-1:
+
 	/* Save BIST */
 	movl	%eax, %ebp
+1:
+
+	/* Save table pointer */
+	movl	%ecx, %esi
 
 	/* Load the segement registers to match the GDT loaded in start16.S */
 	movl	$(X86_GDT_ENTRY_32BIT_DS * X86_GDT_ENTRY_SIZE), %eax
@@ -133,7 +144,13 @@ car_init_ret:
 	movl	%esi, (%edx)
 
 skip_hob:
+#else
+	/* Store table pointer */
+	movl	%esp, %edx
+	addl	$GD_TABLE, %edx
+	movl	%esi, (%edx)
 #endif
+
 	/* Setup first parameter to setup_gdt, pointer to global_data */
 	movl	%esp, %eax
 

arch/x86/include/asm/global_data.h

@@ -69,6 +69,7 @@ struct arch_global_data {
 	char *mrc_output;
 	unsigned int mrc_output_len;
 	void *gdt;			/* Global descriptor table */
+	ulong table;			/* Table pointer from previous loader */
 };
 
 #endif

arch/x86/lib/asm-offsets.c

@@ -21,5 +21,6 @@ int main(void)
 #ifdef CONFIG_HAVE_FSP
 	DEFINE(GD_HOB_LIST, offsetof(gd_t, arch.hob_list));
 #endif
+	DEFINE(GD_TABLE, offsetof(gd_t, arch.table));
 	return 0;
 }