Snow bootblock (bloated/debug version)

This is the bloated Snow bootblock which includes:
- SPI driver
- UART, including requisite I2C, Maxim PMIC, and clock config code.
- Adjustments for magic offsets (id section, stack pointer address)

This is just a temporary solution until we have romstage loading.
Once that happens, we'll rip out all but the code necessary for
copying SPI ROM content into SRAM.

Change-Id: I2a11e272eb9b6f626b5d9783eabb4a720a1d06be
Signed-off-by: David Hendricks <dhendrix@chromium.org>
Reviewed-on: http://review.coreboot.org/2170
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>

src/arch/armv7/Makefile.inc

@@ -259,7 +259,7 @@ $(objcbfs)/bootblock.debug: $(objgenerated)/bootblock.o $(objgenerated)/bootbloc
 ifeq ($(CONFIG_COMPILER_LLVM_CLANG),y)
 	$(LD) -m armelf_linux_eabi -static -o $@.tmp -L$(obj) $< -T $(objgenerated)/bootblock.ld
 else
-	$(CC) -nostdlib -nostartfiles -static -o $@ -L$(obj) -T $(objgenerated)/bootblock.ld $<
+	$(CC) -nostdlib -nostartfiles -static -o $@ -L$(obj) -T $(objgenerated)/bootblock.ld -Wl,--start-group $< $(LIBGCC_FILE_NAME) -Wl,--end-group
 endif
 
 ################################################################################

src/arch/armv7/bootblock_simple.c

@@ -40,6 +40,7 @@ void main(unsigned long bist)
 
 	if (boot_cpu()) {
 		bootblock_mainboard_init();
+		bootblock_cpu_init();
 	}
 
 	entry = findstage(target1);

src/arch/armv7/lib/id.lds

@@ -1,6 +1,6 @@
 SECTIONS {
 	/* FIXME: determine a sensible location... */
-	. = (0x2024000) - (__id_end - __id_start);
+	. = (0x2026400);
 	.id (.): {
 		*(.id)
 	}

src/arch/armv7/romstage.ld

@@ -35,11 +35,11 @@
 OUTPUT_FORMAT("elf32-littlearm", "elf32-littlearm", "elf32-littlearm")
 OUTPUT_ARCH(arm)
 
-ENTRY(_start)
+/* ENTRY(_start) */
 
 SECTIONS
 {
-	. = CONFIG_ROMSTAGE_BASE;
+	. = 0x02023400 + 0x4000;
 
 	.romtext . : {
 		_rom = .;

src/cpu/samsung/exynos5250/Kconfig

@@ -45,7 +45,7 @@ config IRAM_TOP
 
 config SYS_INIT_SP_ADDR
 	hex
-	default 0x0204F800
+	default 0x02058000
 
 config IRAM_STACK
 	hex

src/cpu/samsung/exynos5250/bootblock.c

@@ -17,16 +17,24 @@
  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
  */
 
+#if 0
+/*
+ * Set/clear program flow prediction and return the previous state.
+ */
+static int config_branch_prediction(int set_cr_z)
+{
+	unsigned int cr;
+
+	/* System Control Register: 11th bit Z Branch prediction enable */
+	cr = get_cr();
+	set_cr(set_cr_z ? cr | CR_Z : cr & ~CR_Z);
+
+	return cr & CR_Z;
+}
+#endif
+
 void bootblock_cpu_init(void);
 void bootblock_cpu_init(void)
 {
-	/*
+	/* FIXME: this is a stub for now */
-	 * FIXME: this is a stub for now. It should eventually copy
-	 * romstage data (and maybe more) from SPI to SRAM.
-	 */
-#if 0
-	volatile unsigned long *addr = (unsigned long *)0x1004330c;
-	*addr |= 0x100;
-	while (1) ;
-#endif
 }

src/mainboard/google/snow/Kconfig

@@ -56,6 +56,10 @@ config MAINBOARD_VENDOR
 	string
 	default "Samsung"
 
+config BOOTBLOCK_MAINBOARD_INIT
+	string
+	default "mainboard/google/snow/bootblock.c"
+
 # SPL (second-phase loader) stuff
 config SPL_TEXT_BASE
 	hex