Move generic architectural setup out of blx_plat_arch_setup().

blx_plat_arch_setup() should only perform platform-specific
architectural setup, e.g. enabling the MMU.  This patch moves
generic architectural setup code out of blx_plat_arch_setup().

Change-Id: I4ccf56b8c4a2fa84909817779a2d97a14aaafab6

arch/aarch64/cpu/cpu_helpers.S

@@ -39,14 +39,9 @@ cpu_reset_handler:; .type cpu_reset_handler, %function
 	mov	x19, x30 // lr
 
 	/* ---------------------------------------------
-	 * As a bare minimal enable the SMP bit and the
-	 * I$ for all aarch64 processors. Also set the
-	 * exception vector to something sane.
+	 * As a bare minimal enable the SMP bit.
 	 * ---------------------------------------------
 	 */
-	adr	x0, early_exceptions
-	bl	write_vbar
-
 	bl	read_midr
 	lsr	x0, x0, #MIDR_PN_SHIFT
 	and	x0, x0, #MIDR_PN_MASK
@@ -59,8 +54,4 @@ smp_setup_begin:
 	orr	x0, x0, #CPUECTLR_SMP_BIT
 	bl	write_cpuectlr
 smp_setup_end:
-	bl	read_sctlr
-	orr	x0, x0, #SCTLR_I_BIT
-	bl	write_sctlr
-
 	ret	x19

bl1/aarch64/bl1_entrypoint.S

@@ -28,6 +28,7 @@
  * POSSIBILITY OF SUCH DAMAGE.
  */
 
+#include <arch.h>
 
 	.globl	reset_handler
 
@@ -49,6 +50,23 @@ reset_handler:; .type reset_handler, %function
 	 */
 	bl	cpu_reset_handler
 
+	/* ---------------------------------------------
+	 * Set the exception vector to something sane.
+	 * ---------------------------------------------
+	 */
+	adr	x0, early_exceptions
+	msr	vbar_el3, x0
+
+	/* ---------------------------------------------
+	 * Enable the instruction cache.
+	 * ---------------------------------------------
+	 */
+	mrs	x0, sctlr_el3
+	orr	x0, x0, #SCTLR_I_BIT
+	msr	sctlr_el3, x0
+
+	isb
+
 _wait_for_entrypoint:
 	/* ---------------------------------------------
 	 * Find the type of reset and jump to handler

bl2/aarch64/bl2_entrypoint.S

@@ -29,6 +29,7 @@
  */
 
 #include <bl_common.h>
+#include <arch.h>
 
 
 	.globl	bl2_entrypoint
@@ -59,6 +60,23 @@ bl2_entrypoint:; .type bl2_entrypoint, %function
 	bl	platform_is_primary_cpu
 	cbz	x0, _panic
 
+	/* ---------------------------------------------
+	 * Set the exception vector to something sane.
+	 * ---------------------------------------------
+	 */
+	adr	x0, early_exceptions
+	msr	vbar_el1, x0
+
+	/* ---------------------------------------------
+	 * Enable the instruction cache.
+	 * ---------------------------------------------
+	 */
+	mrs	x0, sctlr_el1
+	orr	x0, x0, #SCTLR_I_BIT
+	msr	sctlr_el1, x0
+
+	isb
+
 	/* --------------------------------------------
 	 * Give ourselves a small coherent stack to
 	 * ease the pain of initializing the MMU

bl31/aarch64/bl31_entrypoint.S

@@ -31,6 +31,7 @@
 #include <bl1.h>
 #include <bl_common.h>
 #include <platform.h>
+#include <arch.h>
 
 
 	.globl	bl31_entrypoint
@@ -50,8 +51,29 @@ bl31_entrypoint:; .type bl31_entrypoint, %function
 	 * indicating BL31 should be run, memory layout
 	 * of the trusted SRAM available to BL31 and
 	 * information about running the non-trusted
-	 * software already loaded by BL2. Check the
-	 * opcode out of paranoia.
+	 * software already loaded by BL2.
+	 * ---------------------------------------------
+	 */
+
+	/* ---------------------------------------------
+	 * Set the exception vector to something sane.
+	 * ---------------------------------------------
+	 */
+	adr	x1, runtime_exceptions
+	msr	vbar_el3, x1
+
+	/* ---------------------------------------------
+	 * Enable the instruction cache.
+	 * ---------------------------------------------
+	 */
+	mrs	x1, sctlr_el3
+	orr	x1, x1, #SCTLR_I_BIT
+	msr	sctlr_el3, x1
+
+	isb
+
+	/* ---------------------------------------------
+	 * Check the opcodes out of paranoia.
 	 * ---------------------------------------------
 	 */
 	mov	x19, #RUN_IMAGE

plat/fvp/bl2_plat_setup.c

@@ -124,24 +124,9 @@ void bl2_platform_setup()
  ******************************************************************************/
 void bl2_plat_arch_setup()
 {
-	unsigned long sctlr;
-
-	/* Enable instruction cache. */
-	sctlr = read_sctlr();
-	sctlr |= SCTLR_I_BIT;
-	write_sctlr(sctlr);
-
-	/*
-	 * Very simple exception vectors which assert if any exception other
-	 * than a single SMC call from BL2 to pass control to BL31 in EL3 is
-	 * received.
-	 */
-	write_vbar((unsigned long) early_exceptions);
-
 	configure_mmu(&bl2_tzram_layout,
 		      (unsigned long) &BL2_RO_BASE,
 		      (unsigned long) &BL2_STACKS_BASE,
 		      (unsigned long) &BL2_COHERENT_RAM_BASE,
 		      (unsigned long) &BL2_RW_BASE);
-	return;
 }

plat/fvp/bl31_plat_setup.c

@@ -166,14 +166,6 @@ void bl31_platform_setup()
  ******************************************************************************/
 void bl31_plat_arch_setup()
 {
-	unsigned long sctlr;
-
-	/* Enable instruction cache. */
-	sctlr = read_sctlr();
-	sctlr |= SCTLR_I_BIT;
-	write_sctlr(sctlr);
-
-	write_vbar((unsigned long) runtime_exceptions);
 	configure_mmu(&bl31_tzram_layout,
 		      (unsigned long) &BL31_RO_BASE,
 		      (unsigned long) &BL31_STACKS_BASE,