Merge branch 'for-next/rpi4'

25 files changed, 659 insertions, 221 deletions

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 8a1d75c19b..59fce0c601 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -60,6 +60,8 @@ config ARCH_BCM283X
 	select OFTREE
 	select OFDEVICE
 	select HAVE_PBL_MULTI_IMAGES
+	select CPU_SUPPORTS_32BIT_KERNEL
+	select CPU_SUPPORTS_64BIT_KERNEL
 
 config ARCH_CLPS711X
 	bool "Cirrus Logic EP711x/EP721x/EP731x"
@@ -276,7 +278,7 @@ config ARCH_ZYNQMP
 	select OFDEVICE
 	select OFTREE
 	select RELOCATABLE
-	select SYS_SUPPORTS_64BIT_KERNEL
+	select CPU_SUPPORTS_64BIT_KERNEL
 	select HAS_MACB
 
 config ARCH_ARM64_VIRT
@@ -286,7 +288,7 @@ config ARCH_ARM64_VIRT
 	select OFDEVICE
 	select OFTREE
 	select RELOCATABLE
-	select SYS_SUPPORTS_64BIT_KERNEL
+	select CPU_SUPPORTS_64BIT_KERNEL
 	select ARM_AMBA
 	select BOARD_ARM_VIRT
 	select HW_HAS_PCI
@@ -397,13 +399,13 @@ choice
 
 config 32BIT
 	bool "32-bit barebox"
-	depends on CPU_SUPPORTS_32BIT_KERNEL && SYS_SUPPORTS_32BIT_KERNEL
+	depends on CPU_SUPPORTS_32BIT_KERNEL
 	help
 	  Select this option if you want to build a 32-bit barebox.
 
 config 64BIT
 	bool "64-bit barebox"
-	depends on CPU_SUPPORTS_64BIT_KERNEL && SYS_SUPPORTS_64BIT_KERNEL
+	depends on CPU_SUPPORTS_64BIT_KERNEL
 	select ARCH_DMA_ADDR_T_64BIT
 	help
 	  Select this option if you want to build a 64-bit barebox.
diff --git a/arch/arm/boards/raspberry-pi/Makefile b/arch/arm/boards/raspberry-pi/Makefile
index 6f995b5640..e4f91b4979 100644
--- a/arch/arm/boards/raspberry-pi/Makefile
+++ b/arch/arm/boards/raspberry-pi/Makefile
@@ -2,4 +2,5 @@
 
 obj-$(CONFIG_MACH_RPI_COMMON) += rpi-common.o
 lwl-y += lowlevel.o
+obj-pbl-y += mbox-helpers.o
 bbenv-y += defaultenv-rpi
diff --git a/arch/arm/boards/raspberry-pi/lowlevel.c b/arch/arm/boards/raspberry-pi/lowlevel.c
index 7b9809b86c..5ead895767 100644
--- a/arch/arm/boards/raspberry-pi/lowlevel.c
+++ b/arch/arm/boards/raspberry-pi/lowlevel.c
@@ -4,7 +4,10 @@
 #include <asm/cache.h>
 #include <common.h>
 #include <linux/sizes.h>
+#include <asm/unaligned.h>
 #include <mach/platform.h>
+#include <debug_ll.h>
+#include <mach/mbox.h>
 #include <of.h>
 
 #include "lowlevel.h"
@@ -33,7 +36,7 @@ static void copy_vc_fdt(void *dest, void *src, unsigned long max_size)
 	memmove(dest, src, size);
 }
 
-/* A pointer to the FDT created by VideoCore was passed to us in r2. We
+/* A pointer to the FDT created by VideoCore was passed to us in x0/r2. We
  * reserve some memory just above the region used for Barebox and copy
  * this FDT there. We fetch it from there later in rpi_devices_init().
  */
@@ -45,8 +48,6 @@ static inline void start_raspberry_pi(unsigned long memsize, void *fdt,
 {
 	unsigned long endmem = rpi_stack_top(memsize);
 
-	arm_cpu_lowlevel_init();
-
 	copy_vc_fdt((void *)endmem, vc_fdt, VIDEOCORE_FDT_SZ);
 
 	fdt += get_runtime_offset();
@@ -54,29 +55,123 @@ static inline void start_raspberry_pi(unsigned long memsize, void *fdt,
 	barebox_arm_entry(BCM2835_SDRAM_BASE, endmem - BCM2835_SDRAM_BASE, fdt);
 }
 
-#define RPI_ENTRY_FUNCTION(name, memsize, r2) \
-	ENTRY_FUNCTION_WITHSTACK(name, rpi_stack_top(memsize), __r0, __r1, r2)
+#ifdef CONFIG_CPU_V8
+#define RPI_ENTRY_FUNCTION(name, memsize, fdt) \
+	ENTRY_FUNCTION_WITHSTACK(name, rpi_stack_top(memsize), fdt, __x1, __x2)
+#else
+#define RPI_ENTRY_FUNCTION(name, memsize, fdt) \
+	ENTRY_FUNCTION_WITHSTACK(name, rpi_stack_top(memsize), __r0, __r1, fdt)
+#endif
+
+extern char __dtb_z_bcm2835_rpi_start[];
+extern char __dtb_z_bcm2836_rpi_2_start[];
+extern char __dtb_z_bcm2837_rpi_3_start[];
+extern char __dtb_z_bcm2837_rpi_cm3_start[];
+extern char __dtb_z_bcm2711_rpi_4_start[];
+
+RPI_ENTRY_FUNCTION(start_raspberry_pi1, SZ_128M, fdt)
+{
+	arm_cpu_lowlevel_init();
+
+	start_raspberry_pi(SZ_128M, __dtb_z_bcm2835_rpi_start, (void *)fdt);
+}
+
+RPI_ENTRY_FUNCTION(start_raspberry_pi2, SZ_512M, fdt)
+{
+	arm_cpu_lowlevel_init();
+
+	start_raspberry_pi(SZ_512M, __dtb_z_bcm2836_rpi_2_start, (void *)fdt);
+}
 
-extern char __dtb_bcm2835_rpi_start[];
-RPI_ENTRY_FUNCTION(start_raspberry_pi1, SZ_128M, r2)
+RPI_ENTRY_FUNCTION(start_raspberry_pi3, SZ_512M, fdt)
 {
-	start_raspberry_pi(SZ_128M, __dtb_bcm2835_rpi_start, (void *)r2);
+	arm_cpu_lowlevel_init();
+
+	start_raspberry_pi(SZ_512M, __dtb_z_bcm2837_rpi_3_start, (void *)fdt);
 }
 
-extern char __dtb_bcm2836_rpi_2_start[];
-RPI_ENTRY_FUNCTION(start_raspberry_pi2, SZ_512M, r2)
+RPI_ENTRY_FUNCTION(start_raspberry_pi_cm3, SZ_512M, fdt)
 {
-	start_raspberry_pi(SZ_512M, __dtb_bcm2836_rpi_2_start, (void *)r2);
+	arm_cpu_lowlevel_init();
+
+	start_raspberry_pi(SZ_512M, __dtb_z_bcm2837_rpi_cm3_start, (void *)fdt);
 }
 
-extern char __dtb_bcm2837_rpi_3_start[];
-RPI_ENTRY_FUNCTION(start_raspberry_pi3, SZ_512M, r2)
+#define DT_IF_ENABLED(dt, cfg) \
+	(IS_ENABLED(cfg) ? (dt) : NULL)
+
+static void *rpi_get_board_fdt(int rev)
 {
-	start_raspberry_pi(SZ_512M, __dtb_bcm2837_rpi_3_start, (void *)r2);
+	if (!(rev & 0x800000))
+		return DT_IF_ENABLED(__dtb_z_bcm2835_rpi_start, CONFIG_MACH_RPI);
+
+	switch (((rev >> 4) & 0xff)) {
+	case BCM2835_BOARD_REV_A:
+	case BCM2835_BOARD_REV_B:
+	case BCM2835_BOARD_REV_A_PLUS:
+	case BCM2835_BOARD_REV_B_PLUS:
+	case BCM2835_BOARD_REV_CM1:
+	case BCM2835_BOARD_REV_ZERO:
+	case BCM2835_BOARD_REV_ZERO_W:
+		return DT_IF_ENABLED(__dtb_z_bcm2835_rpi_start, CONFIG_MACH_RPI);
+
+	case BCM2836_BOARD_REV_2_B:
+		return DT_IF_ENABLED(__dtb_z_bcm2836_rpi_2_start, CONFIG_MACH_RPI2);
+
+	case BCM2837_BOARD_REV_3_B:
+	case BCM2837B0_BOARD_REV_3B_PLUS:
+	case BCM2837B0_BOARD_REV_3A_PLUS:
+	case BCM2837B0_BOARD_REV_ZERO_2:
+		return DT_IF_ENABLED(__dtb_z_bcm2837_rpi_3_start, CONFIG_MACH_RPI3);
+
+	case BCM2837_BOARD_REV_CM3:
+	case BCM2837B0_BOARD_REV_CM3_PLUS:
+		return DT_IF_ENABLED(__dtb_z_bcm2837_rpi_cm3_start, CONFIG_MACH_RPI_CM3);
+
+	case BCM2711_BOARD_REV_4_B:
+	case BCM2711_BOARD_REV_400:
+	case BCM2711_BOARD_REV_CM4:
+		return DT_IF_ENABLED(__dtb_z_bcm2711_rpi_4_start, CONFIG_MACH_RPI4);
+	}
+
+	return NULL;
 }
 
-extern char __dtb_bcm2837_rpi_cm3_start[];
-RPI_ENTRY_FUNCTION(start_raspberry_pi_cm3, SZ_512M, r2)
+RPI_ENTRY_FUNCTION(start_raspberry_pi_generic, SZ_128M, vc_fdt)
 {
-	start_raspberry_pi(SZ_512M, __dtb_bcm2837_rpi_cm3_start, (void *)r2);
+	void *fdt = NULL;
+	ssize_t memsize;
+	int rev;
+
+	arm_cpu_lowlevel_init();
+
+	debug_ll_init();
+
+	putc_ll('>');
+
+	relocate_to_current_adr();
+	setup_c();
+
+	memsize = rpi_get_arm_mem();
+	if (memsize < 0) {
+		pr_warn("mbox: failed to query ARM memory size. 128M assumed.\n");
+		memsize = SZ_128M;
+	}
+
+	rev = rpi_get_board_rev();
+	if (rev >= 0) {
+		pr_debug("Detected revision %08x\n", rev);
+		fdt = rpi_get_board_fdt(rev);
+	}
+
+	if (!fdt) {
+		fdt = (void *)vc_fdt;
+
+		pr_warn("Unknown Rpi board with rev %08x.\n", rev);
+
+		if (get_unaligned_be32(fdt) != 0xd00dfeed)
+			panic("No suitable built-in or videocore-supplied DT\n");
+	}
+
+	start_raspberry_pi(memsize, fdt, (void *)vc_fdt);
 }
diff --git a/arch/arm/boards/raspberry-pi/lowlevel.h b/arch/arm/boards/raspberry-pi/lowlevel.h
index eacf973fb6..a29860d607 100644
--- a/arch/arm/boards/raspberry-pi/lowlevel.h
+++ b/arch/arm/boards/raspberry-pi/lowlevel.h
@@ -3,9 +3,14 @@
 #ifndef __ARCH_ARM_BOARDS_LOWLEVEL_H__
 #define __ARCH_ARM_BOARDS_LOWLEVEL_H__
 
+#include <linux/types.h>
 #include <linux/sizes.h>
 
 #define VIDEOCORE_FDT_SZ SZ_1M
 #define VIDEOCORE_FDT_ERROR 0xdeadfeed
 
+ssize_t rpi_get_arm_mem(void);
+int rpi_get_usbethaddr(u8 mac[6]);
+int rpi_get_board_rev(void);
+
 #endif /* __ARCH_ARM_BOARDS_LOWLEVEL_H__ */
diff --git a/arch/arm/boards/raspberry-pi/mbox-helpers.c b/arch/arm/boards/raspberry-pi/mbox-helpers.c
new file mode 100644
index 0000000000..9f252c68ff
--- /dev/null
+++ b/arch/arm/boards/raspberry-pi/mbox-helpers.c
@@ -0,0 +1,73 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+// SPDX-FileCopyrightText: 2009 Carlo Caione <carlo@carlocaione.org>
+
+#include <mach/mbox.h>
+#include "lowlevel.h"
+
+struct msg_get_arm_mem {
+	struct bcm2835_mbox_hdr hdr;
+	struct bcm2835_mbox_tag_get_arm_mem get_arm_mem;
+	u32 end_tag;
+};
+
+struct msg_get_board_rev {
+	struct bcm2835_mbox_hdr hdr;
+	struct bcm2835_mbox_tag_get_board_rev get_board_rev;
+	u32 end_tag;
+};
+
+struct msg_get_mac_address {
+	struct bcm2835_mbox_hdr hdr;
+	struct bcm2835_mbox_tag_get_mac_address get_mac_address;
+	u32 end_tag;
+};
+
+ssize_t rpi_get_arm_mem(void)
+{
+	BCM2835_MBOX_STACK_ALIGN(struct msg_get_arm_mem, msg);
+	int ret;
+
+	BCM2835_MBOX_INIT_HDR(msg);
+	BCM2835_MBOX_INIT_TAG(&msg->get_arm_mem, GET_ARM_MEMORY);
+
+	ret = bcm2835_mbox_call_prop(BCM2835_MBOX_PROP_CHAN, &msg->hdr);
+	if (ret)
+		return ret;
+
+	return msg->get_arm_mem.body.resp.mem_size;
+}
+
+int rpi_get_usbethaddr(u8 mac[6])
+{
+	BCM2835_MBOX_STACK_ALIGN(struct msg_get_mac_address, msg);
+	int ret;
+
+	BCM2835_MBOX_INIT_HDR(msg);
+	BCM2835_MBOX_INIT_TAG(&msg->get_mac_address, GET_MAC_ADDRESS);
+
+	ret = bcm2835_mbox_call_prop(BCM2835_MBOX_PROP_CHAN, &msg->hdr);
+	if (ret) {
+		pr_info("bcm2835: Could not query MAC address\n");
+		return ret;
+	}
+
+	memcpy(mac, msg->get_mac_address.body.resp.mac, 6);
+	return 0;
+}
+
+int rpi_get_board_rev(void)
+{
+	int ret;
+
+	BCM2835_MBOX_STACK_ALIGN(struct msg_get_board_rev, msg);
+	BCM2835_MBOX_INIT_HDR(msg);
+	BCM2835_MBOX_INIT_TAG(&msg->get_board_rev, GET_BOARD_REV);
+
+	ret = bcm2835_mbox_call_prop(BCM2835_MBOX_PROP_CHAN, &msg->hdr);
+	if (ret) {
+		pr_err("Could not query board revision\n");
+		return ret;
+	}
+
+	return msg->get_board_rev.body.resp.rev;
+}
diff --git a/arch/arm/boards/raspberry-pi/rpi-common.c b/arch/arm/boards/raspberry-pi/rpi-common.c
index 05d59ae6bf..77935e5c88 100644
--- a/arch/arm/boards/raspberry-pi/rpi-common.c
+++ b/arch/arm/boards/raspberry-pi/rpi-common.c
@@ -23,13 +23,28 @@
 #include <linux/sizes.h>
 #include <globalvar.h>
 #include <asm/system_info.h>
+#include <reset_source.h>
 
 #include <mach/core.h>
 #include <mach/mbox.h>
 #include <mach/platform.h>
 
+#include <soc/bcm283x/wdt.h>
+
 #include "lowlevel.h"
 
+//https://www.raspberrypi.com/documentation/computers/raspberry-pi.html#BOOT_ORDER
+static const char * const boot_mode_names[] = {
+	[0x0] = "unknown",
+	[0x1] = "sd",
+	[0x2] = "net",
+	[0x3] = "rpiboot",
+	[0x4] = "usbmsd",
+	[0x5] = "usbc",
+	[0x6] = "nvme",
+	[0x7] = "http",
+};
+
 struct rpi_priv;
 struct rpi_machine_data {
 	int (*init)(struct rpi_priv *priv);
@@ -45,57 +60,14 @@ struct rpi_priv {
 	const char *name;
 };
 
-struct msg_get_arm_mem {
-	struct bcm2835_mbox_hdr hdr;
-	struct bcm2835_mbox_tag_get_arm_mem get_arm_mem;
-	u32 end_tag;
-};
-
-struct msg_get_board_rev {
-	struct bcm2835_mbox_hdr hdr;
-	struct bcm2835_mbox_tag_get_board_rev get_board_rev;
-	u32 end_tag;
-};
-
-struct msg_get_mac_address {
-	struct bcm2835_mbox_hdr hdr;
-	struct bcm2835_mbox_tag_get_mac_address get_mac_address;
-	u32 end_tag;
-};
-
-static int rpi_get_arm_mem(u32 *size)
-{
-	BCM2835_MBOX_STACK_ALIGN(struct msg_get_arm_mem, msg);
-	int ret;
-
-	BCM2835_MBOX_INIT_HDR(msg);
-	BCM2835_MBOX_INIT_TAG(&msg->get_arm_mem, GET_ARM_MEMORY);
-
-	ret = bcm2835_mbox_call_prop(BCM2835_MBOX_PROP_CHAN, &msg->hdr);
-	if (ret)
-		return ret;
-
-	*size = msg->get_arm_mem.body.resp.mem_size;
-
-	return 0;
-}
-
 static void rpi_set_usbethaddr(void)
 {
-	BCM2835_MBOX_STACK_ALIGN(struct msg_get_mac_address, msg);
-	int ret;
+	u8 mac[ETH_ALEN];
 
-	BCM2835_MBOX_INIT_HDR(msg);
-	BCM2835_MBOX_INIT_TAG(&msg->get_mac_address, GET_MAC_ADDRESS);
+	if (rpi_get_usbethaddr(mac))
+		return; /* Ignore error; not critical */
 
-	ret = bcm2835_mbox_call_prop(BCM2835_MBOX_PROP_CHAN, &msg->hdr);
-	if (ret) {
-		printf("bcm2835: Could not query MAC address\n");
-		/* Ignore error; not critical */
-		return;
-	}
-
-	eth_register_ethaddr(0, msg->get_mac_address.body.resp.mac);
+	eth_register_ethaddr(0, mac);
 }
 
 static void rpi_set_usbotg(const char *alias)
@@ -185,48 +157,19 @@ static int rpi_0_w_init(struct rpi_priv *priv)
 	return of_device_disable_by_alias("serial0");
 }
 
-static int rpi_get_board_rev(struct rpi_priv *priv)
-{
-	int ret;
-
-	BCM2835_MBOX_STACK_ALIGN(struct msg_get_board_rev, msg);
-	BCM2835_MBOX_INIT_HDR(msg);
-	BCM2835_MBOX_INIT_TAG(&msg->get_board_rev, GET_BOARD_REV);
-
-	ret = bcm2835_mbox_call_prop(BCM2835_MBOX_PROP_CHAN, &msg->hdr);
-	if (ret) {
-		dev_err(priv->dev, "Could not query board revision\n");
-		return ret;
-	}
-
-	/* Comments from u-boot:
-	 * For details of old-vs-new scheme, see:
-	 * https://github.com/pimoroni/RPi.version/blob/master/RPi/version.py
-	 * http://www.raspberrypi.org/forums/viewtopic.php?f=63&t=99293&p=690282
-	 * (a few posts down)
-	 *
-	 * For the RPi 1, bit 24 is the "warranty bit", so we mask off just the
-	 * lower byte to use as the board rev:
-	 * http://www.raspberrypi.org/forums/viewtopic.php?f=63&t=98367&start=250
-	 * http://www.raspberrypi.org/forums/viewtopic.php?f=31&t=20594
-	 */
-	priv->hw_id = msg->get_board_rev.body.resp.rev;
-
-	return 0;
-}
-
 static int rpi_mem_init(void)
 {
-	u32 size = 0;
-	int ret;
+	ssize_t size;
 
-	ret = rpi_get_arm_mem(&size);
-	if (ret)
+	size = rpi_get_arm_mem();
+	if (size < 0) {
 		printf("could not query ARM memory size\n");
+		size = get_ram_size((ulong *) BCM2835_SDRAM_BASE, SZ_128M);
+	}
 
 	bcm2835_add_device_sdram(size);
 
-	return ret;
+	return 0;
 }
 mem_initcall(rpi_mem_init);
 
@@ -258,54 +201,133 @@ static int rpi_env_init(void)
 	return 0;
 }
 
-/* Extract /chosen/bootargs from the VideoCore FDT into vc.bootargs
- * global variable. */
-static int rpi_vc_fdt_bootargs(void *fdt)
+/* Some string properties in fdt passed to us from vc may be
+ * malformed by not being null terminated, so just create and
+ * return a fixed copy.
+ */
+static char *of_read_vc_string(struct device_node *node,
+			       const char *prop_name)
+{
+	int len;
+	const char *str;
+
+	str = of_get_property(node, prop_name, &len);
+	if (!str) {
+		pr_warn("no property '%s' found in vc fdt's '%s' node\n",
+			prop_name, node->full_name);
+		return NULL;
+	}
+	return xstrndup(str, len);
+}
+
+static enum reset_src_type rpi_decode_pm_rsts(struct device_node *chosen,
+					      struct device_node *bootloader)
 {
-	int ret = 0;
-	struct device_node *root = NULL, *node;
-	const char *cmdline;
+	u32 pm_rsts;
+	int ret;
+
+	ret = of_property_read_u32(chosen, "pm_rsts", &pm_rsts);
+	if (ret && bootloader)
+		 ret = of_property_read_u32(bootloader, "rsts", &pm_rsts);
+
+	if (ret) {
+		pr_warn("'pm_rsts' value not found in vc fdt\n");
+		return RESET_UKWN;
+	}
+	/*
+	 * https://github.com/raspberrypi/linux/issues/932#issuecomment-93989581
+	 */
+
+	if (pm_rsts & PM_RSTS_HADPOR_SET)
+		return RESET_POR;
+	if (pm_rsts & PM_RSTS_HADDR_SET)
+		return RESET_JTAG;
+	if (pm_rsts & PM_RSTS_HADWR_SET)
+		return RESET_WDG;
+	if (pm_rsts & PM_RSTS_HADSR_SET)
+		return RESET_RST;
+
+	return RESET_UKWN;
+}
+
+static u32 rpi_boot_mode, rpi_boot_part;
+/* Extract useful information from the VideoCore FDT we got.
+ * Some parameters are defined here:
+ * https://www.raspberrypi.com/documentation/computers/configuration.html#part4
+ */
+static void rpi_vc_fdt_parse(void *fdt)
+{
+	int ret;
+	struct device_node *root, *chosen, *bootloader;
+	char *str;
 
 	root = of_unflatten_dtb(fdt, INT_MAX);
-	if (IS_ERR(root)) {
-		ret = PTR_ERR(root);
-		root = NULL;
-		goto out;
+	if (IS_ERR(root))
+		return;
+
+	str = of_read_vc_string(root, "serial-number");
+	if (str) {
+		barebox_set_serial_number(str);
+		free(str);
 	}
 
-	node = of_find_node_by_path_from(root, "/chosen");
-	if (!node) {
-		pr_err("no /chosen node\n");
-		ret = -ENOENT;
-		goto out;
+	str = of_read_vc_string(root, "model");
+	if (str) {
+		barebox_set_model(str);
+		free(str);
 	}
 
-	cmdline = of_get_property(node, "bootargs", NULL);
-	if (!cmdline) {
-		pr_err("no bootargs property in the /chosen node\n");
-		ret = -ENOENT;
+	chosen = of_find_node_by_path_from(root, "/chosen");
+	if (!chosen) {
+		pr_err("no '/chosen' node found in vc fdt\n");
 		goto out;
 	}
 
-	globalvar_add_simple("vc.bootargs", cmdline);
+	bootloader = of_find_node_by_name(chosen, "bootloader");
 
-	switch(cpu_architecture()) {
-	case CPU_ARCH_ARMv6:
-		globalvar_add_simple("vc.kernel", "kernel.img");
-		break;
-	case CPU_ARCH_ARMv7:
-		globalvar_add_simple("vc.kernel", "kernel7.img");
-		break;
-	case CPU_ARCH_ARMv8:
-		globalvar_add_simple("vc.kernel", "kernel7l.img");
-		break;
+	str = of_read_vc_string(chosen, "bootargs");
+	if (str) {
+		globalvar_add_simple("vc.bootargs", str);
+		free(str);
 	}
 
+	str = of_read_vc_string(chosen, "overlay_prefix");
+	if (str) {
+		globalvar_add_simple("vc.overlay_prefix", str);
+		free(str);
+	}
+
+	str = of_read_vc_string(chosen, "os_prefix");
+	if (str) {
+		globalvar_add_simple("vc.os_prefix", str);
+		free(str);
+	}
+
+	ret = of_property_read_u32(chosen, "boot-mode", &rpi_boot_mode);
+	if (ret && bootloader)
+		ret = of_property_read_u32(bootloader, "boot-mode", &rpi_boot_mode);
+	if (ret)
+		pr_debug("'boot-mode' property not found in vc fdt\n");
+	else
+		globalvar_add_simple_enum("vc.boot_mode", &rpi_boot_mode,
+					  boot_mode_names,
+					  ARRAY_SIZE(boot_mode_names));
+
+	ret = of_property_read_u32(chosen, "partition", &rpi_boot_part);
+	if (ret && bootloader)
+		ret = of_property_read_u32(bootloader, "partition", &rpi_boot_part);
+	if (ret)
+		pr_debug("'partition' property not found in vc fdt\n");
+	else
+		globalvar_add_simple_int("vc.boot_partition", &rpi_boot_part, "%u");
+
+	if (IS_ENABLED(CONFIG_RESET_SOURCE))
+		reset_source_set(rpi_decode_pm_rsts(chosen, bootloader));
+
 out:
 	if (root)
 		of_delete_node(root);
-
-	return ret;
+	return;
 }
 
 static void rpi_vc_fdt(void)
@@ -313,7 +335,6 @@ static void rpi_vc_fdt(void)
 	void *saved_vc_fdt;
 	struct fdt_header *oftree;
 	unsigned long magic, size;
-	int ret;
 
 	/* VideoCore FDT was copied in PBL just above Barebox memory */
 	saved_vc_fdt = (void *)(arm_mem_endmem_get());
@@ -332,16 +353,23 @@ static void rpi_vc_fdt(void)
 		return;
 
 	size = be32_to_cpu(oftree->totalsize);
-	if (write_file("/vc.dtb", saved_vc_fdt, size)) {
+	if (write_file("/vc.dtb", saved_vc_fdt, size))
 		pr_err("failed to save videocore fdt to a file\n");
-		return;
-	}
 
-	ret = rpi_vc_fdt_bootargs(saved_vc_fdt);
-	if (ret) {
-		pr_err("failed to extract bootargs from videocore fdt: %d\n",
-									ret);
-		return;
+	rpi_vc_fdt_parse(saved_vc_fdt);
+}
+
+static void rpi_set_kernel_name(void) {
+	switch(cpu_architecture()) {
+	case CPU_ARCH_ARMv6:
+		globalvar_add_simple("vc.kernel", "kernel.img");
+		break;
+	case CPU_ARCH_ARMv7:
+		globalvar_add_simple("vc.kernel", "kernel7.img");
+		break;
+	case CPU_ARCH_ARMv8:
+		globalvar_add_simple("vc.kernel", "kernel8.img");
+		break;
 	}
 }
 
@@ -355,6 +383,18 @@ static const struct rpi_machine_data *rpi_get_dcfg(struct rpi_priv *priv)
 		return NULL;
 	}
 
+	/* Comments from u-boot:
+	 * For details of old-vs-new scheme, see:
+	 * https://github.com/pimoroni/RPi.version/blob/master/RPi/version.py
+	 * http://www.raspberrypi.org/forums/viewtopic.php?f=63&t=99293&p=690282
+	 * (a few posts down)
+	 *
+	 * For the RPi 1, bit 24 is the "warranty bit", so we mask off just the
+	 * lower byte to use as the board rev:
+	 * http://www.raspberrypi.org/forums/viewtopic.php?f=63&t=98367&start=250
+	 * http://www.raspberrypi.org/forums/viewtopic.php?f=31&t=20594
+	 */
+
 	for (; dcfg->hw_id != U8_MAX; dcfg++) {
 		if (priv->hw_id & 0x800000) {
 			if (dcfg->hw_id != ((priv->hw_id >> 4) & 0xff))
@@ -386,10 +426,12 @@ static int rpi_devices_probe(struct device_d *dev)
 	priv = xzalloc(sizeof(*priv));
 	priv->dev = dev;
 
-	ret = rpi_get_board_rev(priv);
-	if (ret)
+	ret = rpi_get_board_rev();
+	if (ret < 0)
 		goto free_priv;
 
+	priv->hw_id = ret;
+
 	dcfg = rpi_get_dcfg(priv);
 	if (IS_ERR(dcfg))
 		goto free_priv;
@@ -406,6 +448,7 @@ static int rpi_devices_probe(struct device_d *dev)
 	armlinux_set_architecture(MACH_TYPE_BCM2708);
 	rpi_env_init();
 	rpi_vc_fdt();
+	rpi_set_kernel_name();
 
 	if (dcfg && dcfg->init)
 		dcfg->init(priv);
@@ -532,6 +575,18 @@ static const struct rpi_machine_data rpi_3_ids[] = {
 	},
 };
 
+static const struct rpi_machine_data rpi_4_ids[] = {
+	{
+		.hw_id = BCM2711_BOARD_REV_4_B,
+	}, {
+		.hw_id = BCM2711_BOARD_REV_400,
+	}, {
+		.hw_id = BCM2711_BOARD_REV_CM4,
+	}, {
+		.hw_id = U8_MAX
+	},
+};
+
 static const struct of_device_id rpi_of_match[] = {
 	/* BCM2835 based Boards */
 	{ .compatible = "raspberrypi,model-a", .data = rpi_1_ids },
@@ -556,6 +611,11 @@ static const struct of_device_id rpi_of_match[] = {
 	{ .compatible = "raspberrypi,3-compute-module", .data = rpi_3_ids },
 	{ .compatible = "raspberrypi,3-compute-module-lite", .data = rpi_3_ids },
 
+	/* BCM2711 based Boards */
+	{ .compatible = "raspberrypi,4-model-b", .data = rpi_4_ids },
+	{ .compatible = "raspberrypi,4-compute-module", .data = rpi_4_ids },
+	{ .compatible = "raspberrypi,400", .data = rpi_4_ids },
+
 	{ /* sentinel */ },
 };
 BAREBOX_DEEP_PROBE_ENABLE(rpi_of_match);
diff --git a/arch/arm/configs/rpi_defconfig b/arch/arm/configs/rpi_defconfig
index e0e1497481..e7d695f8ae 100644
--- a/arch/arm/configs/rpi_defconfig
+++ b/arch/arm/configs/rpi_defconfig
@@ -24,7 +24,6 @@ CONFIG_BOOTM_OFTREE=y
 CONFIG_BLSPEC=y
 CONFIG_CONSOLE_ALLOW_COLOR=y
 CONFIG_DEFAULT_ENVIRONMENT_GENERIC_NEW=y
-CONFIG_DEFAULT_ENVIRONMENT_PATH=""
 CONFIG_CMD_DMESG=y
 CONFIG_LONGHELP=y
 CONFIG_CMD_IOMEM=y
@@ -83,6 +82,8 @@ CONFIG_SERIAL_AMBA_PL011=y
 CONFIG_DRIVER_SERIAL_NS16550=y
 CONFIG_NET_USB=y
 CONFIG_NET_USB_SMSC95XX=y
+CONFIG_I2C=y
+CONFIG_I2C_BCM283X=y
 CONFIG_USB_HOST=y
 CONFIG_USB_DWC2_HOST=y
 CONFIG_MCI=y
diff --git a/arch/arm/configs/rpi_v8a_defconfig b/arch/arm/configs/rpi_v8a_defconfig
new file mode 100644
index 0000000000..e218311a72
--- /dev/null
+++ b/arch/arm/configs/rpi_v8a_defconfig
@@ -0,0 +1,112 @@
+CONFIG_ARCH_BCM283X=y
+CONFIG_MACH_RPI3=y
+CONFIG_MACH_RPI_CM3=y
+CONFIG_MACH_RPI4=y
+CONFIG_64BIT=y
+CONFIG_IMAGE_COMPRESSION_NONE=y
+CONFIG_MMU=y
+# CONFIG_MMU_EARLY is not set
+CONFIG_MALLOC_SIZE=0x0
+CONFIG_MALLOC_TLSF=y
+CONFIG_KALLSYMS=y
+CONFIG_PROMPT="R-Pi> "
+CONFIG_HUSH_FANCY_PROMPT=y
+CONFIG_CMDLINE_EDITING=y
+CONFIG_AUTO_COMPLETE=y
+CONFIG_MENU=y
+CONFIG_BOOTM_SHOW_TYPE=y
+CONFIG_BOOTM_VERBOSE=y
+CONFIG_BOOTM_INITRD=y
+CONFIG_BOOTM_OFTREE=y
+CONFIG_BLSPEC=y
+CONFIG_CONSOLE_ACTIVATE_ALL=y
+CONFIG_CONSOLE_ALLOW_COLOR=y
+CONFIG_PBL_CONSOLE=y
+CONFIG_DEFAULT_ENVIRONMENT_GENERIC_NEW=y
+CONFIG_CMD_DMESG=y
+CONFIG_LONGHELP=y
+CONFIG_CMD_IOMEM=y
+CONFIG_CMD_IMD=y
+CONFIG_CMD_MEMINFO=y
+CONFIG_CMD_REGULATOR=y
+CONFIG_CMD_GO=y
+CONFIG_CMD_LOADB=y
+CONFIG_CMD_LOADY=y
+CONFIG_CMD_RESET=y
+CONFIG_CMD_UIMAGE=y
+CONFIG_CMD_PARTITION=y
+CONFIG_CMD_EXPORT=y
+CONFIG_CMD_DEFAULTENV=y
+CONFIG_CMD_LOADENV=y
+CONFIG_CMD_PRINTENV=y
+CONFIG_CMD_MAGICVAR=y
+CONFIG_CMD_MAGICVAR_HELP=y
+CONFIG_CMD_SAVEENV=y
+CONFIG_CMD_CMP=y
+CONFIG_CMD_FILETYPE=y
+CONFIG_CMD_LN=y
+CONFIG_CMD_MD5SUM=y
+CONFIG_CMD_SHA1SUM=y
+CONFIG_CMD_SHA256SUM=y
+CONFIG_CMD_UNCOMPRESS=y
+CONFIG_CMD_LET=y
+CONFIG_CMD_MSLEEP=y
+CONFIG_CMD_SLEEP=y
+CONFIG_CMD_DHCP=y
+CONFIG_CMD_MIITOOL=y
+CONFIG_CMD_PING=y
+CONFIG_CMD_ECHO_E=y
+CONFIG_CMD_EDIT=y
+CONFIG_CMD_LOGIN=y
+CONFIG_CMD_MENU=y
+CONFIG_CMD_MENU_MANAGEMENT=y
+CONFIG_CMD_PASSWD=y
+CONFIG_CMD_READLINE=y
+CONFIG_CMD_TIMEOUT=y
+CONFIG_CMD_CRC=y
+CONFIG_CMD_CRC_CMP=y
+CONFIG_CMD_MM=y
+CONFIG_CMD_CLK=y
+CONFIG_CMD_DETECT=y
+CONFIG_CMD_GPIO=y
+CONFIG_CMD_LED=y
+CONFIG_CMD_LED_TRIGGER=y
+CONFIG_CMD_WD=y
+CONFIG_CMD_OF_NODE=y
+CONFIG_CMD_OF_PROPERTY=y
+CONFIG_CMD_OFTREE=y
+CONFIG_CMD_TIME=y
+CONFIG_NET=y
+CONFIG_SERIAL_AMBA_PL011=y
+CONFIG_DRIVER_SERIAL_NS16550=y
+CONFIG_NET_USB=y
+CONFIG_NET_USB_SMSC95XX=y
+CONFIG_I2C=y
+CONFIG_I2C_BCM283X=y
+CONFIG_USB_HOST=y
+CONFIG_USB_DWC2_HOST=y
+CONFIG_USB_DWC2_GADGET=y
+CONFIG_USB_GADGET=y
+# CONFIG_USB_GADGET_AUTOSTART is not set
+CONFIG_MCI=y
+CONFIG_MCI_BCM283X=y
+CONFIG_MCI_BCM283X_SDHOST=y
+CONFIG_LED=y
+CONFIG_LED_GPIO=y
+CONFIG_LED_GPIO_OF=y
+CONFIG_LED_TRIGGERS=y
+CONFIG_WATCHDOG=y
+CONFIG_WATCHDOG_BCM2835=y
+CONFIG_GPIO_RASPBERRYPI_EXP=y
+CONFIG_PINCTRL_BCM283X=y
+CONFIG_REGULATOR=y
+CONFIG_REGULATOR_FIXED=y
+CONFIG_GENERIC_PHY=y
+CONFIG_USB_NOP_XCEIV=y
+CONFIG_FS_EXT4=y
+CONFIG_FS_TFTP=y
+CONFIG_FS_NFS=y
+CONFIG_FS_FAT=y
+CONFIG_FS_FAT_WRITE=y
+CONFIG_FS_FAT_LFN=y
+CONFIG_ZLIB=y
diff --git a/arch/arm/cpu/Kconfig b/arch/arm/cpu/Kconfig
index 0a493754a4..9b5a833abf 100644
--- a/arch/arm/cpu/Kconfig
+++ b/arch/arm/cpu/Kconfig
@@ -87,7 +87,6 @@ config CPU_V7
 config CPU_V8
 	bool
 	select CPU_64v8
-	select CPU_SUPPORTS_64BIT_KERNEL
 	select ARM_EXCEPTIONS
 	select GENERIC_FIND_NEXT_BIT
 	select ARCH_HAS_STACK_DUMP
@@ -156,12 +155,6 @@ config CACHE_L2X0
 	bool "Enable L2x0 PrimeCell"
 	depends on MMU && ARCH_HAS_L2X0
 
-config SYS_SUPPORTS_32BIT_KERNEL
-	bool
-
-config SYS_SUPPORTS_64BIT_KERNEL
-	bool
-
 config CPU_SUPPORTS_32BIT_KERNEL
 	bool
 
diff --git a/arch/arm/dts/Makefile b/arch/arm/dts/Makefile
index 723bd2a123..0c7e43e226 100644
--- a/arch/arm/dts/Makefile
+++ b/arch/arm/dts/Makefile
@@ -114,6 +114,7 @@ lwl-$(CONFIG_MACH_RPI) += bcm2835-rpi.dtb.o
 lwl-$(CONFIG_MACH_RPI2) += bcm2836-rpi-2.dtb.o
 lwl-$(CONFIG_MACH_RPI3) += bcm2837-rpi-3.dtb.o
 lwl-$(CONFIG_MACH_RPI_CM3) += bcm2837-rpi-cm3.dtb.o
+lwl-$(CONFIG_MACH_RPI4) += bcm2711-rpi-4.dtb.o
 lwl-$(CONFIG_MACH_SABRELITE) += imx6q-sabrelite.dtb.o imx6dl-sabrelite.dtb.o
 lwl-$(CONFIG_MACH_SABRESD) += imx6q-sabresd.dtb.o imx6qp-sabresd.dtb.o
 lwl-$(CONFIG_MACH_FREESCALE_IMX6SX_SABRESDB) += imx6sx-sdb.dtb.o
diff --git a/arch/arm/dts/bcm2711-rpi-4.dts b/arch/arm/dts/bcm2711-rpi-4.dts
new file mode 100644
index 0000000000..3c0caa73f8
--- /dev/null
+++ b/arch/arm/dts/bcm2711-rpi-4.dts
@@ -0,0 +1,18 @@
+#include <arm64/broadcom/bcm2711-rpi-4-b.dts>
+
+&{/memory@0} {
+	reg = <0x0 0x0 0x0>;
+};
+
+&sdhci {
+	/* no use for SDIO WiFi in barebox */
+	status = "disabled";
+};
+
+&uart1 {
+	/* VPU core clock is reported at 200MHz, but needs to be 500Mhz
+	 * for ns16550 driver to set correct baudrate. Until that's
+	 * figured out, hardcode clock frequency to the expected value
+	 */
+	clock-frequency = <500000000>;
+};
diff --git a/arch/arm/include/asm/cputype.h b/arch/arm/include/asm/cputype.h
index 7dc027c174..c3fc057650 100644
--- a/arch/arm/include/asm/cputype.h
+++ b/arch/arm/include/asm/cputype.h
@@ -6,6 +6,23 @@
 #include <linux/stringify.h>
 #include <linux/kernel.h>
 
+#ifdef CONFIG_CPU_64v8
+
+#define CPUID_ID	midr_el1
+#define CPUID_CACHETYPE	ctr_el0
+#define CPUID_MPIDR	mpidr_el1
+
+#define read_cpuid(reg)							\
+	({								\
+		unsigned int __val;					\
+		asm("mrs	%0, " __stringify(reg)			\
+		    : "=r" (__val)					\
+		    :							\
+		    : "cc");						\
+		__val;							\
+	})
+#else
+
 #define CPUID_ID	0
 #define CPUID_CACHETYPE	1
 #define CPUID_TCM	2
@@ -27,8 +44,6 @@
 #define CPUID_EXT_ISAR4	"c2, 4"
 #define CPUID_EXT_ISAR5	"c2, 5"
 
-extern unsigned int processor_id;
-
 #define read_cpuid(reg)							\
 	({								\
 		unsigned int __val;					\
@@ -47,6 +62,9 @@ extern unsigned int processor_id;
 		    : "cc");						\
 		__val;							\
 	})
+#endif
+
+extern unsigned int processor_id;
 
 /*
  * The CPU ID never changes at run time, so we might as well tell the
diff --git a/arch/arm/include/asm/dma.h b/arch/arm/include/asm/dma.h
index 226b1c1464..75a6c1ad86 100644
--- a/arch/arm/include/asm/dma.h
+++ b/arch/arm/include/asm/dma.h
@@ -10,6 +10,7 @@ static inline void *dma_alloc(size_t size)
 }
 
 #ifndef CONFIG_MMU
+#define dma_alloc_coherent dma_alloc_coherent
 static inline void *dma_alloc_coherent(size_t size, dma_addr_t *dma_handle)
 {
 	void *ret = xmemalign(4096, size);
@@ -21,22 +22,26 @@ static inline void *dma_alloc_coherent(size_t size, dma_addr_t *dma_handle)
 	return ret;
 }
 
+#define dma_alloc_writecombine dma_alloc_writecombine
 static inline void *dma_alloc_writecombine(size_t size, dma_addr_t *dma_handle)
 {
 	return dma_alloc_coherent(size, dma_handle);
 }
 
+#define dma_free_coherent dma_free_coherent
 static inline void dma_free_coherent(void *mem, dma_addr_t dma_handle,
 				     size_t size)
 {
 	free(mem);
 }
 
+#define dma_sync_single_for_cpu dma_sync_single_for_cpu
 static inline void dma_sync_single_for_cpu(dma_addr_t address, size_t size,
 					   enum dma_data_direction dir)
 {
 }
 
+#define dma_sync_single_for_device dma_sync_single_for_device
 static inline void dma_sync_single_for_device(dma_addr_t address, size_t size,
 					      enum dma_data_direction dir)
 {
diff --git a/arch/arm/include/asm/system_info.h b/arch/arm/include/asm/system_info.h
index c7f9987748..5a84fde75b 100644
--- a/arch/arm/include/asm/system_info.h
+++ b/arch/arm/include/asm/system_info.h
@@ -44,6 +44,12 @@
 #define CPU_IS_CORTEX_A15	0x410fc0f0
 #define CPU_IS_CORTEX_A15_MASK	0xff0ffff0
 
+#define CPU_IS_CORTEX_A53	0x410fd030
+#define CPU_IS_CORTEX_A53_MASK	0xff0ffff0
+
+#define CPU_IS_CORTEX_A72	0x410fd080
+#define CPU_IS_CORTEX_A72_MASK	0xff0ffff0
+
 #define CPU_IS_PXA250		0x69052100
 #define CPU_IS_PXA250_MASK	0xfffff7f0
 
diff --git a/arch/arm/mach-bcm283x/Kconfig b/arch/arm/mach-bcm283x/Kconfig
index 75acee8dad..48209fb5c6 100644
--- a/arch/arm/mach-bcm283x/Kconfig
+++ b/arch/arm/mach-bcm283x/Kconfig
@@ -8,30 +8,51 @@ config ARCH_TEXT_BASE
 
 config MACH_RPI_COMMON
 	bool
+	select ARM_USE_COMPRESSED_DTB
+
+config MACH_RPI_AARCH_32_64
+	select MACH_RPI_COMMON
+	select CPU_V7 if 32BIT
+	select ARM_SECURE_MONITOR if 32BIT
+	select CPU_V8 if 64BIT
+	select BOARD_ARM_GENERIC_DT if 64BIT
+	bool
+	help
+	  Select this from CPUs that support both AArch32 and AArch64
+	  execution modes. barebox can be compiled for only one of
+	  these states, depending on the value of
+	  CONFIG_32BIT/CONFIG_64BIT.
 
 menu "select Broadcom BCM283X boards to be built"
 
 config MACH_RPI
 	bool "RaspberryPi (BCM2835/ARM1176JZF-S)"
+	depends on 32BIT
 	select CPU_V6
 	select MACH_RPI_COMMON
 
 config MACH_RPI2
 	bool "RaspberryPi 2 (BCM2836/CORTEX-A7)"
+	depends on 32BIT
 	select CPU_V7
 	select MACH_RPI_COMMON
 
 config MACH_RPI3
 	bool "RaspberryPi 3 (BCM2837/CORTEX-A53)"
-	select CPU_V7
+	select MACH_RPI_AARCH_32_64
 	select MACH_RPI_COMMON
-	select ARM_SECURE_MONITOR
+	depends on 32BIT || (64BIT && !MMU_EARLY)
 
 config MACH_RPI_CM3
 	bool "RaspberryPi Compute Module 3 (BCM2837/CORTEX-A53)"
-	select CPU_V7
+	select MACH_RPI_AARCH_32_64
+	select MACH_RPI_COMMON
+	depends on 32BIT || (64BIT && !MMU_EARLY)
+
+config MACH_RPI4
+	bool "RaspberryPi 4 (BCM2711/CORTEX-A72)"
+	select MACH_RPI_AARCH_32_64
 	select MACH_RPI_COMMON
-	select ARM_SECURE_MONITOR
 
 endmenu
 
diff --git a/arch/arm/mach-bcm283x/Makefile b/arch/arm/mach-bcm283x/Makefile
index e5ef78af97..53343cec8c 100644
--- a/arch/arm/mach-bcm283x/Makefile
+++ b/arch/arm/mach-bcm283x/Makefile
@@ -1,3 +1,3 @@
 # SPDX-License-Identifier: GPL-2.0-only
 
-obj-y += core.o mbox.o
+obj-pbl-y += mbox.o core.o
diff --git a/arch/arm/mach-bcm283x/core.c b/arch/arm/mach-bcm283x/core.c
index f2528cf1f1..40882fb6d6 100644
--- a/arch/arm/mach-bcm283x/core.c
+++ b/arch/arm/mach-bcm283x/core.c
@@ -1,40 +1,29 @@
-/*
- * Author: Carlo Caione <carlo@carlocaione.org>
- *
- * Based on mach-nomadik
- * Copyright (C) 2009 Jean-Christophe PLAGNIOL-VILLARD <plagnio@jcrosoft.com>
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License as
- * published by the Free Software Foundation; either version 2 of
- * the License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- */
+// SPDX-License-Identifier: GPL-2.0-only
 
-#include <common.h>
-#include <init.h>
-
-#include <linux/clk.h>
-#include <linux/clkdev.h>
-#include <linux/err.h>
-
-#include <io.h>
-#include <asm/armlinux.h>
-#include <linux/sizes.h>
-
-#include <mach/platform.h>
+#include <linux/types.h>
 #include <mach/core.h>
-#include <linux/amba/bus.h>
+#include <asm/system_info.h>
 
-void bcm2835_add_device_sdram(u32 size)
+void __iomem *bcm2835_get_mmio_base_by_cpuid(void)
 {
-	if (!size)
-		size = get_ram_size((ulong *) BCM2835_SDRAM_BASE, SZ_128M);
+	static u32 cpuid;
+
+	if (!cpuid) {
+		cpuid = read_cpuid_id();
+		pr_debug("ARM CPUID: %08x\n", cpuid);
+	}
+
+	/* We know ARM1167, Cortex A-7, A-53 and A-72 CPUID mask is identical */
+	switch(cpuid & CPU_IS_ARM1176_MASK) {
+	case CPU_IS_ARM1176:	/* bcm2835 */
+		return IOMEM(0x20000000);
+	case CPU_IS_CORTEX_A7:	/* bcm2836 */
+	case CPU_IS_CORTEX_A53:	/* bcm2837 */
+		return IOMEM(0x3f000000);
+	case CPU_IS_CORTEX_A72:	/* bcm2711 */
+		return IOMEM(0xfe000000);
+	}
 
-	arm_add_mem_device("ram0", BCM2835_SDRAM_BASE, size);
+	pr_err("Couldn't determine rpi by CPUID %08x\n", cpuid);
+	return NULL;
 }
diff --git a/arch/arm/mach-bcm283x/include/mach/core.h b/arch/arm/mach-bcm283x/include/mach/core.h
index a1c47f9154..c8547351a3 100644
--- a/arch/arm/mach-bcm283x/include/mach/core.h
+++ b/arch/arm/mach-bcm283x/include/mach/core.h
@@ -1,28 +1,27 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * Copyright (C) 2009 Carlo Caione <carlo@carlocaione.org>
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License as
- * published by the Free Software Foundation; either version 2 of
- * the License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
  */
 
 #ifndef __BCM2835_CORE_H__
 #define __BCM2835_CORE_H__
 
+#include <common.h>
+#include <linux/types.h>
+#include <linux/sizes.h>
+#include <asm/memory.h>
 #include <mach/platform.h>
 
-void bcm2835_add_device_sdram(u32 size);
+static void inline bcm2835_add_device_sdram(u32 size)
+{
+	arm_add_mem_device("ram0", BCM2835_SDRAM_BASE, size);
+}
 
 static void inline bcm2835_register_fb(void)
 {
 	add_generic_device("bcm2835_fb", 0, NULL, 0, 0, 0, NULL);
 }
 
+void __iomem *bcm2835_get_mmio_base_by_cpuid(void);
+
 #endif
diff --git a/arch/arm/mach-bcm283x/include/mach/debug_ll.h b/arch/arm/mach-bcm283x/include/mach/debug_ll.h
index 4bfa5abc7c..fdb63b4f5a 100644
--- a/arch/arm/mach-bcm283x/include/mach/debug_ll.h
+++ b/arch/arm/mach-bcm283x/include/mach/debug_ll.h
@@ -18,6 +18,7 @@
 #define __MACH_BCM2835_DEBUG_LL_H__
 
 #include <mach/platform.h>
+#include <io.h>
 
 #ifdef CONFIG_DEBUG_RPI1_UART
 
@@ -66,6 +67,31 @@ static inline void debug_ll_init(void)
 	debug_ll_ns16550_init(divisor);
 }
 
+#elif defined CONFIG_DEBUG_RPI4_MINI_UART
+
+static inline uint8_t debug_ll_read_reg(int reg)
+{
+	return readb(BCM2711_MINIUART_BASE + (reg << 2));
+}
+
+static inline void debug_ll_write_reg(int reg, uint8_t val)
+{
+	writeb(val, BCM2711_MINIUART_BASE + (reg << 2));
+}
+
+#include <debug_ll/ns16550.h>
+
+static inline void debug_ll_init(void)
+{
+	/* Configured by ROM */
+}
+
+#else
+
+static inline void debug_ll_init(void)
+{
+}
+
 #endif
 
 #endif /* __MACH_BCM2835_DEBUG_LL_H__ */
diff --git a/arch/arm/mach-bcm283x/include/mach/mbox.h b/arch/arm/mach-bcm283x/include/mach/mbox.h
index a9f06512bc..92cadba62c 100644
--- a/arch/arm/mach-bcm283x/include/mach/mbox.h
+++ b/arch/arm/mach-bcm283x/include/mach/mbox.h
@@ -171,7 +171,10 @@ struct bcm2835_mbox_tag_hdr {
 #define BCM2837B0_BOARD_REV_3B_PLUS   	0x0d
 #define BCM2837B0_BOARD_REV_3A_PLUS   	0x0e
 #define BCM2837B0_BOARD_REV_CM3_PLUS	0x10
+#define BCM2711_BOARD_REV_4_B		0x11
 #define BCM2837B0_BOARD_REV_ZERO_2	0x12
+#define BCM2711_BOARD_REV_400		0x13
+#define BCM2711_BOARD_REV_CM4		0x14
 
 struct bcm2835_mbox_tag_get_board_rev {
 	struct bcm2835_mbox_tag_hdr tag_hdr;
@@ -273,6 +276,7 @@ struct bcm2835_mbox_tag_set_power_state {
 #define BCM2835_MBOX_CLOCK_ID_SDRAM	8
 #define BCM2835_MBOX_CLOCK_ID_PIXEL	9
 #define BCM2835_MBOX_CLOCK_ID_PWM	10
+#define BCM2835_MBOX_CLOCK_ID_EMMC2	12
 
 struct bcm2835_mbox_tag_get_clock_rate {
 	struct bcm2835_mbox_tag_hdr tag_hdr;
diff --git a/arch/arm/mach-bcm283x/include/mach/platform.h b/arch/arm/mach-bcm283x/include/mach/platform.h
index 310f2463f2..b957ac8de3 100644
--- a/arch/arm/mach-bcm283x/include/mach/platform.h
+++ b/arch/arm/mach-bcm283x/include/mach/platform.h
@@ -31,9 +31,10 @@
 #define BCM2835_CACHELINE_SIZE	64
 
 #define BCM2835_PL011_BASE 0x20201000
-#define BCM2836_PL011_BASE 0x3f201000
+#define BCM2836_PL011_BASE 0x3f201000UL
 #define BCM2835_MINIUART_BASE 0x20215040
-#define BCM2836_MINIUART_BASE 0x3f215040
+#define BCM2836_MINIUART_BASE 0x3f215040UL
+#define BCM2711_MINIUART_BASE 0xfe215040UL
 
 #endif
 
diff --git a/arch/arm/mach-bcm283x/mbox.c b/arch/arm/mach-bcm283x/mbox.c
index 4b14afcfe4..4959a1a652 100644
--- a/arch/arm/mach-bcm283x/mbox.c
+++ b/arch/arm/mach-bcm283x/mbox.c
@@ -14,13 +14,20 @@
 #include <init.h>
 #include <io.h>
 #include <of_address.h>
+#include <pbl.h>
 
 #include <mach/mbox.h>
+#include <mach/core.h>
 
 #define TIMEOUT (MSECOND * 1000)
 
 static void __iomem *mbox_base;
 
+#ifdef __PBL__
+#define is_timeout_non_interruptible(start, timeout) ((void)start, 0)
+#define get_time_ns() 0
+#endif
+
 static int bcm2835_mbox_call_raw(u32 chan, struct bcm2835_mbox_hdr *buffer,
 					u32 *recv)
 {
@@ -109,19 +116,20 @@ static void dump_buf(struct bcm2835_mbox_hdr *buffer)
 }
 #endif
 
-static int bcm2835_mbox_probe(void)
+static void __iomem *bcm2835_mbox_probe(void)
 {
 	struct device_node *mbox_node;
 
+	if (IN_PBL)
+		return bcm2835_get_mmio_base_by_cpuid() + 0xb880;
+
 	mbox_node = of_find_compatible_node(NULL, NULL, "brcm,bcm2835-mbox");
 	if (!mbox_node) {
 		pr_err("Missing mbox node\n");
-		return -ENOENT;
+		return NULL;
 	}
 
-	mbox_base = of_iomap(mbox_node, 0);
-
-	return 0;
+	return of_iomap(mbox_node, 0);
 }
 
 int bcm2835_mbox_call_prop(u32 chan, struct bcm2835_mbox_hdr *buffer)
@@ -132,9 +140,9 @@ int bcm2835_mbox_call_prop(u32 chan, struct bcm2835_mbox_hdr *buffer)
 	int tag_index;
 
 	if (!mbox_base) {
-		ret = bcm2835_mbox_probe();
-		if (ret)
-			return ret;
+		mbox_base = bcm2835_mbox_probe();
+		if (!mbox_base)
+			return -ENOENT;
 	}
 
 	pr_debug("mbox: TX buffer\n");
@@ -143,7 +151,7 @@ int bcm2835_mbox_call_prop(u32 chan, struct bcm2835_mbox_hdr *buffer)
 	ret = bcm2835_mbox_call_raw(chan, buffer, &rbuffer);
 	if (ret)
 		return ret;
-	if (rbuffer != (u32)buffer) {
+	if (rbuffer != (uintptr_t)buffer) {
 		pr_err("mbox: Response buffer mismatch\n");
 		return -EIO;
 	}
diff --git a/arch/arm/mach-imx/Kconfig b/arch/arm/mach-imx/Kconfig
index 6b962dcf7e..9ff549ac83 100644
--- a/arch/arm/mach-imx/Kconfig
+++ b/arch/arm/mach-imx/Kconfig
@@ -177,7 +177,7 @@ config ARCH_IMX8M
 	select CPU_V8
 	select PINCTRL_IMX_IOMUX_V3
 	select OFTREE
-	select SYS_SUPPORTS_64BIT_KERNEL
+	select CPU_SUPPORTS_64BIT_KERNEL
 	select COMMON_CLK_OF_PROVIDER
 	select ARCH_HAS_FEC_IMX
 	select HW_HAS_PCI
diff --git a/arch/arm/mach-layerscape/Kconfig b/arch/arm/mach-layerscape/Kconfig
index bdd7d0dbfe..943a474808 100644
--- a/arch/arm/mach-layerscape/Kconfig
+++ b/arch/arm/mach-layerscape/Kconfig
@@ -17,7 +17,7 @@ config ARCH_LAYERSCAPE_PPA
 
 config ARCH_LS1046
 	select CPU_V8
-	select SYS_SUPPORTS_64BIT_KERNEL
+	select CPU_SUPPORTS_64BIT_KERNEL
 	bool
 
 config MACH_LS1046ARDB
diff --git a/arch/arm/mach-rockchip/Kconfig b/arch/arm/mach-rockchip/Kconfig
index 4b6dfd2c17..1f3ba706ee 100644
--- a/arch/arm/mach-rockchip/Kconfig
+++ b/arch/arm/mach-rockchip/Kconfig
@@ -30,7 +30,7 @@ config ARCH_RK3288
 config ARCH_ROCKCHIP_V8
 	bool
 	select CPU_V8
-	select SYS_SUPPORTS_64BIT_KERNEL
+	select CPU_SUPPORTS_64BIT_KERNEL
 	select ARM_ATF
 	select RELOCATABLE