rpi: move plat_helpers.S to common

The plat_helpers.S file was almost identical between its RPi3 and RPi4
versions. Unify the two files, moving it into the common/ directory.

This adds a plat_rpi_get_model() function, which can be used to trigger
RPi4 specific action, detected at runtime. We use that to do the RPi4
specific L2 cache initialisation.

Change-Id: I2295704fd6dde7c76fe83b6d98c7bf998d4bf074
Signed-off-by: Andre Przywara <andre.przywara@arm.com>

plat/rpi/common/aarch64/plat_helpers.S

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015-2019, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2015-2020, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -20,6 +20,7 @@
 	.globl	plat_reset_handler
 	.globl	plat_rpi3_calc_core_pos
 	.globl	plat_secondary_cold_boot_setup
+	.globl	plat_rpi_get_model
 
 	/* -----------------------------------------------------
 	 *  unsigned int plat_my_core_pos(void)
@@ -56,7 +57,7 @@ endfunc plat_rpi3_calc_core_pos
 func plat_is_my_cpu_primary
 	mrs	x0, mpidr_el1
 	and	x0, x0, #(MPIDR_CLUSTER_MASK | MPIDR_CPU_MASK)
-	cmp	x0, #RPI4_PRIMARY_CPU
+	cmp	x0, #RPI_PRIMARY_CPU
 	cset	w0, eq
 	ret
 endfunc plat_is_my_cpu_primary
@@ -164,11 +165,38 @@ func plat_crash_console_flush
 	b	console_16550_core_flush
 endfunc plat_crash_console_flush
 
+	/* ---------------------------------------------
+	 * int plat_rpi_get_model()
+	 * Macro to determine whether we are running on
+	 * a Raspberry Pi 3 or 4. Just checks the MIDR for
+	 * being either a Cortex-A72 or a Cortex-A53.
+	 * Out : return 4 if RPi4, 3 otherwise.
+	 * Clobber list : x0
+	 * ---------------------------------------------
+	 */
+	.macro _plat_rpi_get_model
+	mrs	x0, midr_el1
+	and	x0, x0, #0xf0	/* Isolate low byte of part number */
+	cmp	w0, #0x80	/* Cortex-A72 (RPi4) is 0xd08, A53 is 0xd03 */
+	mov	w0, #3
+	csinc	w0, w0, w0, ne
+	.endm
+
+	func plat_rpi_get_model
+	_plat_rpi_get_model
+	ret
+	endfunc plat_rpi_get_model
+
 	/* ---------------------------------------------
 	 * void plat_reset_handler(void);
 	 * ---------------------------------------------
 	 */
 func plat_reset_handler
+	/* L2 cache setup only needed on RPi4 */
+	_plat_rpi_get_model
+	cmp	w0, #4
+	b.ne	1f
+
 	/* ------------------------------------------------
 	 * Set L2 read/write cache latency:
 	 * - L2 Data RAM latency: 3 cycles (0b010)
@@ -181,5 +209,6 @@ func plat_reset_handler
 	msr	CORTEX_A72_L2CTLR_EL1, x0
 	isb
 
+1:
 	ret
 endfunc plat_reset_handler

plat/rpi/common/include/rpi_shared.h

@@ -36,4 +36,6 @@ void plat_rpi3_io_setup(void);
 /* VideoCore firmware commands */
 int rpi3_vc_hardware_get_board_revision(uint32_t *revision);
 
+int plat_rpi_get_model(void);
+
 #endif /* RPI3_PRIVATE_H */

plat/rpi/rpi3/aarch64/plat_helpers.S

@@ -1,163 +0,0 @@
-/*
- * Copyright (c) 2015-2018, ARM Limited and Contributors. All rights reserved.
- *
- * SPDX-License-Identifier: BSD-3-Clause
- */
-
-#include <arch.h>
-#include <asm_macros.S>
-#include <assert_macros.S>
-#include <platform_def.h>
-
-	.globl	plat_crash_console_flush
-	.globl	plat_crash_console_init
-	.globl	plat_crash_console_putc
-	.globl	platform_mem_init
-	.globl	plat_get_my_entrypoint
-	.globl	plat_is_my_cpu_primary
-	.globl	plat_my_core_pos
-	.globl	plat_rpi3_calc_core_pos
-	.globl	plat_secondary_cold_boot_setup
-
-	/* -----------------------------------------------------
-	 *  unsigned int plat_my_core_pos(void)
-	 *
-	 *  This function uses the plat_rpi3_calc_core_pos()
-	 *  definition to get the index of the calling CPU.
-	 * -----------------------------------------------------
-	 */
-func plat_my_core_pos
-	mrs	x0, mpidr_el1
-	b	plat_rpi3_calc_core_pos
-endfunc plat_my_core_pos
-
-	/* -----------------------------------------------------
-	 *  unsigned int plat_rpi3_calc_core_pos(u_register_t mpidr);
-	 *
-	 *  CorePos = (ClusterId * 4) + CoreId
-	 * -----------------------------------------------------
-	 */
-func plat_rpi3_calc_core_pos
-	and	x1, x0, #MPIDR_CPU_MASK
-	and	x0, x0, #MPIDR_CLUSTER_MASK
-	add	x0, x1, x0, LSR #6
-	ret
-endfunc plat_rpi3_calc_core_pos
-
-	/* -----------------------------------------------------
-	 * unsigned int plat_is_my_cpu_primary (void);
-	 *
-	 * Find out whether the current cpu is the primary
-	 * cpu.
-	 * -----------------------------------------------------
-	 */
-func plat_is_my_cpu_primary
-	mrs	x0, mpidr_el1
-	and	x0, x0, #(MPIDR_CLUSTER_MASK | MPIDR_CPU_MASK)
-	cmp	x0, #RPI3_PRIMARY_CPU
-	cset	w0, eq
-	ret
-endfunc plat_is_my_cpu_primary
-
-	/* -----------------------------------------------------
-	 * void plat_secondary_cold_boot_setup (void);
-	 *
-	 * This function performs any platform specific actions
-	 * needed for a secondary cpu after a cold reset e.g
-	 * mark the cpu's presence, mechanism to place it in a
-	 * holding pen etc.
-	 * -----------------------------------------------------
-	 */
-func plat_secondary_cold_boot_setup
-	/* Calculate address of our hold entry */
-	bl	plat_my_core_pos
-	lsl	x0, x0, #3
-	mov_imm	x2, PLAT_RPI3_TM_HOLD_BASE
-	add	x0, x0, x2
-
-	/*
-	 * This code runs way before requesting the warmboot of this core,
-	 * so it is possible to clear the mailbox before getting a request
-	 * to boot.
-	 */
-	mov	x1, PLAT_RPI3_TM_HOLD_STATE_WAIT
-	str	x1,[x0]
-
-	/* Wait until we have a go */
-poll_mailbox:
-	wfe
-	ldr	x1, [x0]
-	cmp	x1, PLAT_RPI3_TM_HOLD_STATE_GO
-	bne	poll_mailbox
-
-	/* Jump to the provided entrypoint */
-	mov_imm	x0, PLAT_RPI3_TM_ENTRYPOINT
-	ldr	x1, [x0]
-	br	x1
-endfunc plat_secondary_cold_boot_setup
-
-	/* ---------------------------------------------------------------------
-	 * uintptr_t plat_get_my_entrypoint (void);
-	 *
-	 * Main job of this routine is to distinguish between a cold and a warm
-	 * boot.
-	 *
-	 * This functions returns:
-	 *  - 0 for a cold boot.
-	 *  - Any other value for a warm boot.
-	 * ---------------------------------------------------------------------
-	 */
-func plat_get_my_entrypoint
-	/* TODO: support warm boot */
-	mov	x0, #0
-	ret
-endfunc plat_get_my_entrypoint
-
-	/* ---------------------------------------------
-	 * void platform_mem_init (void);
-	 *
-	 * No need to carry out any memory initialization.
-	 * ---------------------------------------------
-	 */
-func platform_mem_init
-	ret
-endfunc platform_mem_init
-
-	/* ---------------------------------------------
-	 * int plat_crash_console_init(void)
-	 * Function to initialize the crash console
-	 * without a C Runtime to print crash report.
-	 * Clobber list : x0 - x3
-	 * ---------------------------------------------
-	 */
-func plat_crash_console_init
-	mov_imm	x0, PLAT_RPI_MINI_UART_BASE
-	mov	x1, xzr
-	mov	x2, xzr
-	b	console_16550_core_init
-endfunc plat_crash_console_init
-
-	/* ---------------------------------------------
-	 * int plat_crash_console_putc(int c)
-	 * Function to print a character on the crash
-	 * console without a C Runtime.
-	 * Clobber list : x1, x2
-	 * ---------------------------------------------
-	 */
-func plat_crash_console_putc
-	mov_imm	x1, PLAT_RPI_MINI_UART_BASE
-	b	console_16550_core_putc
-endfunc plat_crash_console_putc
-
-	/* ---------------------------------------------
-	 * int plat_crash_console_flush()
-	 * Function to force a write of all buffered
-	 * data that hasn't been output.
-	 * Out : return -1 on error else return 0.
-	 * Clobber list : x0, x1
-	 * ---------------------------------------------
-	 */
-func plat_crash_console_flush
-	mov_imm	x0, PLAT_RPI_MINI_UART_BASE
-	b	console_16550_core_flush
-endfunc plat_crash_console_flush

plat/rpi/rpi3/include/platform_def.h

@@ -24,7 +24,7 @@
 #define PLATFORM_CLUSTER0_CORE_COUNT	PLATFORM_MAX_CPUS_PER_CLUSTER
 #define PLATFORM_CORE_COUNT		PLATFORM_CLUSTER0_CORE_COUNT
 
-#define RPI3_PRIMARY_CPU		U(0)
+#define RPI_PRIMARY_CPU			U(0)
 
 #define PLAT_MAX_PWR_LVL		MPIDR_AFFLVL1
 #define PLAT_NUM_PWR_DOMAINS		(PLATFORM_CLUSTER_COUNT + \

plat/rpi/rpi3/platform.mk

@@ -15,6 +15,7 @@ PLAT_BL_COMMON_SOURCES	:=	drivers/ti/uart/aarch64/16550_console.S	\
 				drivers/gpio/gpio.c			\
 				drivers/delay_timer/delay_timer.c	\
 				drivers/rpi3/gpio/rpi3_gpio.c		\
+				plat/rpi/common/aarch64/plat_helpers.S	\
 				plat/rpi/common/rpi3_common.c		\
 				${XLAT_TABLES_LIB_SRCS}
 
@@ -23,7 +24,6 @@ BL1_SOURCES		+=	drivers/io/io_fip.c			\
 				drivers/io/io_storage.c			\
 				lib/cpus/aarch64/cortex_a53.S		\
 				plat/common/aarch64/platform_mp_stack.S	\
-				plat/rpi/rpi3/aarch64/plat_helpers.S	\
 				plat/rpi/rpi3/rpi3_bl1_setup.c		\
 				plat/rpi/common/rpi3_io_storage.c	\
 				drivers/rpi3/mailbox/rpi3_mbox.c	\
@@ -38,7 +38,6 @@ BL2_SOURCES		+=	common/desc_image_load.c		\
 				drivers/mmc/mmc.c			\
 				drivers/rpi3/sdhost/rpi3_sdhost.c	\
 				plat/common/aarch64/platform_mp_stack.S	\
-				plat/rpi/rpi3/aarch64/plat_helpers.S	\
 				plat/rpi/rpi3/aarch64/rpi3_bl2_mem_params_desc.c \
 				plat/rpi/rpi3/rpi3_bl2_setup.c		\
 				plat/rpi/common/rpi3_image_load.c	\
@@ -46,7 +45,6 @@ BL2_SOURCES		+=	common/desc_image_load.c		\
 
 BL31_SOURCES		+=	lib/cpus/aarch64/cortex_a53.S		\
 				plat/common/plat_psci_common.c		\
-				plat/rpi/rpi3/aarch64/plat_helpers.S	\
 				plat/rpi/rpi3/rpi3_bl31_setup.c		\
 				plat/rpi/common/rpi3_pm.c		\
 				plat/rpi/common/rpi3_topology.c		\

plat/rpi/rpi4/include/platform_def.h

@@ -24,7 +24,7 @@
 #define PLATFORM_CLUSTER0_CORE_COUNT	PLATFORM_MAX_CPUS_PER_CLUSTER
 #define PLATFORM_CORE_COUNT		PLATFORM_CLUSTER0_CORE_COUNT
 
-#define RPI4_PRIMARY_CPU		U(0)
+#define RPI_PRIMARY_CPU			U(0)
 
 #define PLAT_MAX_PWR_LVL		MPIDR_AFFLVL1
 #define PLAT_NUM_PWR_DOMAINS		(PLATFORM_CLUSTER_COUNT + \

plat/rpi/rpi4/platform.mk

@@ -16,7 +16,7 @@ PLAT_BL_COMMON_SOURCES	:=	drivers/ti/uart/aarch64/16550_console.S	\
 				${XLAT_TABLES_LIB_SRCS}
 
 BL31_SOURCES		+=	lib/cpus/aarch64/cortex_a72.S		\
-				plat/rpi/rpi4/aarch64/plat_helpers.S	\
+				plat/rpi/common/aarch64/plat_helpers.S	\
 				plat/rpi/rpi4/aarch64/armstub8_header.S	\
 				drivers/arm/gic/common/gic_common.c     \
 				drivers/arm/gic/v2/gicv2_helpers.c      \