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@@ -1,156 +0,0 @@
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-From ade243a211d62327e9ebadce27bbbff7981e37f0 Mon Sep 17 00:00:00 2001
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-From: =?UTF-8?q?C=C3=A9dric=20Schieli?= <cschieli@gmail.com>
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-Date: Fri, 11 Nov 2016 11:59:07 +0100
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-Subject: [PATCH] rpi: passthrough of the firmware provided FDT blob
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-MIME-Version: 1.0
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-Content-Type: text/plain; charset=UTF-8
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-Content-Transfer-Encoding: 8bit
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-
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-Raspberry firmware used to pass a FDT blob at a fixed address (0x100),
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-but this is not true anymore. The address now depends on both the
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-memory size and the blob size [1].
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-
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-If one wants to passthrough this FDT blob to the kernel, the most
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-reliable way is to save its address from the r2/x0 register in the
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-U-Boot entry point and expose it in a environment variable for
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-further processing.
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-
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-This patch just does this:
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-- save the provided address in the global variable fw_dtb_pointer
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-- expose it in ${fdt_addr} if it points to a a valid FDT blob
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-
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-There are many different ways to use it. One can, for example, use
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-the following script which will extract from the tree the command
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-line built by the firmware, then hand over the blob to a previously
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-loaded kernel:
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-
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-fdt addr ${fdt_addr}
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-fdt get value bootargs /chosen bootargs
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-bootz ${kernel_addr_r} - ${fdt_addr}
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-
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-Alternatively, users relying on sysboot/pxe can simply omit any FDT
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-statement in their extlinux.conf file, U-Boot will automagically pick
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-${fdt_addr} and pass it to the kernel.
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-
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-[1] https://www.raspberrypi.org/forums//viewtopic.php?f=107&t=134018
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-
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-Upstream-Status: Backport
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-
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-Signed-off-by: Cédric Schieli <cschieli@gmail.com>
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-Acked-by: Stephen Warren <swarren@nvidia.com>
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-Signed-off-by: Jonathan Liu <net147@gmail.com>
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----
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- board/raspberrypi/rpi/Makefile | 1 +
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- board/raspberrypi/rpi/lowlevel_init.S | 36 +++++++++++++++++++++++++++++++++++
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- board/raspberrypi/rpi/rpi.c | 29 ++++++++++++++++++++++++++++
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- 3 files changed, 66 insertions(+)
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- create mode 100644 board/raspberrypi/rpi/lowlevel_init.S
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-
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-diff --git a/board/raspberrypi/rpi/Makefile b/board/raspberrypi/rpi/Makefile
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-index 4ce2c98..dcb25ac 100644
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---- a/board/raspberrypi/rpi/Makefile
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-+++ b/board/raspberrypi/rpi/Makefile
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-@@ -5,3 +5,4 @@
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- #
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-
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- obj-y := rpi.o
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-+obj-y += lowlevel_init.o
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-diff --git a/board/raspberrypi/rpi/lowlevel_init.S b/board/raspberrypi/rpi/lowlevel_init.S
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-new file mode 100644
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-index 0000000..cdbd8e1
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---- /dev/null
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-+++ b/board/raspberrypi/rpi/lowlevel_init.S
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-@@ -0,0 +1,36 @@
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-+/*
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-+ * (C) Copyright 2016
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-+ * Cédric Schieli <cschieli@gmail.com>
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-+ *
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-+ * SPDX-License-Identifier: GPL-2.0+
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-+ */
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-+
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-+#include <config.h>
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-+
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-+.align 8
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-+.global fw_dtb_pointer
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-+fw_dtb_pointer:
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-+#ifdef CONFIG_ARM64
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-+ .dword 0x0
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-+#else
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-+ .word 0x0
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-+#endif
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-+
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-+/*
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-+ * Routine: save_boot_params (called after reset from start.S)
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-+ * Description: save ATAG/FDT address provided by the firmware at boot time
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-+ */
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-+
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-+.global save_boot_params
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-+save_boot_params:
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-+
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-+ /* The firmware provided ATAG/FDT address can be found in r2/x0 */
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-+#ifdef CONFIG_ARM64
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-+ adr x8, fw_dtb_pointer
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-+ str x0, [x8]
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-+#else
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-+ str r2, fw_dtb_pointer
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-+#endif
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-+
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-+ /* Returns */
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-+ b save_boot_params_ret
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-diff --git a/board/raspberrypi/rpi/rpi.c b/board/raspberrypi/rpi/rpi.c
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-index 6245b36..ffd6d31 100644
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---- a/board/raspberrypi/rpi/rpi.c
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-+++ b/board/raspberrypi/rpi/rpi.c
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-@@ -25,6 +25,9 @@
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-
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- DECLARE_GLOBAL_DATA_PTR;
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-
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-+/* From lowlevel_init.S */
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-+extern unsigned long fw_dtb_pointer;
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-+
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- static const struct bcm2835_gpio_platdata gpio_platdata = {
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- .base = BCM2835_GPIO_BASE,
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- };
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-@@ -285,6 +288,31 @@ static void set_fdtfile(void)
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- setenv("fdtfile", fdtfile);
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- }
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-
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-+/*
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-+ * If the firmware provided a valid FDT at boot time, let's expose it in
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-+ * ${fdt_addr} so it may be passed unmodified to the kernel.
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-+ */
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-+static void set_fdt_addr(void)
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-+{
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-+ if (getenv("fdt_addr"))
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-+ return;
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-+
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-+ if (fdt_magic(fw_dtb_pointer) != FDT_MAGIC)
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-+ return;
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-+
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-+ setenv_hex("fdt_addr", fw_dtb_pointer);
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-+}
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-+
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-+/*
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-+ * Prevent relocation from stomping on a firmware provided FDT blob.
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-+ */
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-+unsigned long board_get_usable_ram_top(unsigned long total_size)
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-+{
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-+ if ((gd->ram_top - fw_dtb_pointer) > SZ_64M)
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-+ return gd->ram_top;
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-+ return fw_dtb_pointer & ~0xffff;
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-+}
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-+
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- static void set_usbethaddr(void)
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- {
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- ALLOC_CACHE_ALIGN_BUFFER(struct msg_get_mac_address, msg, 1);
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-@@ -356,6 +384,7 @@ static void set_serial_number(void)
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-
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- int misc_init_r(void)
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- {
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-+ set_fdt_addr();
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- set_fdtfile();
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- set_usbethaddr();
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- #ifdef CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG
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---
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-2.10.2
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-
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Mirza Krak