diff options
Diffstat (limited to 'import-layers/meta-raspberrypi/recipes-bsp/u-boot/files/0002-rpi-passthrough-of-the-firmware-provided-FDT-blob.patch')
| -rw-r--r-- | import-layers/meta-raspberrypi/recipes-bsp/u-boot/files/0002-rpi-passthrough-of-the-firmware-provided-FDT-blob.patch | 156 |
1 files changed, 0 insertions, 156 deletions
diff --git a/import-layers/meta-raspberrypi/recipes-bsp/u-boot/files/0002-rpi-passthrough-of-the-firmware-provided-FDT-blob.patch b/import-layers/meta-raspberrypi/recipes-bsp/u-boot/files/0002-rpi-passthrough-of-the-firmware-provided-FDT-blob.patch deleted file mode 100644 index 323b7ab40..000000000 --- a/import-layers/meta-raspberrypi/recipes-bsp/u-boot/files/0002-rpi-passthrough-of-the-firmware-provided-FDT-blob.patch +++ /dev/null @@ -1,156 +0,0 @@ -From ade243a211d62327e9ebadce27bbbff7981e37f0 Mon Sep 17 00:00:00 2001 -From: =?UTF-8?q?C=C3=A9dric=20Schieli?= <cschieli@gmail.com> -Date: Fri, 11 Nov 2016 11:59:07 +0100 -Subject: [PATCH] rpi: passthrough of the firmware provided FDT blob -MIME-Version: 1.0 -Content-Type: text/plain; charset=UTF-8 -Content-Transfer-Encoding: 8bit - -Raspberry firmware used to pass a FDT blob at a fixed address (0x100), -but this is not true anymore. The address now depends on both the -memory size and the blob size [1]. - -If one wants to passthrough this FDT blob to the kernel, the most -reliable way is to save its address from the r2/x0 register in the -U-Boot entry point and expose it in a environment variable for -further processing. - -This patch just does this: -- save the provided address in the global variable fw_dtb_pointer -- expose it in ${fdt_addr} if it points to a a valid FDT blob - -There are many different ways to use it. One can, for example, use -the following script which will extract from the tree the command -line built by the firmware, then hand over the blob to a previously -loaded kernel: - -fdt addr ${fdt_addr} -fdt get value bootargs /chosen bootargs -bootz ${kernel_addr_r} - ${fdt_addr} - -Alternatively, users relying on sysboot/pxe can simply omit any FDT -statement in their extlinux.conf file, U-Boot will automagically pick -${fdt_addr} and pass it to the kernel. - -[1] https://www.raspberrypi.org/forums//viewtopic.php?f=107&t=134018 - -Upstream-Status: Backport - -Signed-off-by: Cédric Schieli <cschieli@gmail.com> -Acked-by: Stephen Warren <swarren@nvidia.com> -Signed-off-by: Jonathan Liu <net147@gmail.com> ---- - board/raspberrypi/rpi/Makefile | 1 + - board/raspberrypi/rpi/lowlevel_init.S | 36 +++++++++++++++++++++++++++++++++++ - board/raspberrypi/rpi/rpi.c | 29 ++++++++++++++++++++++++++++ - 3 files changed, 66 insertions(+) - create mode 100644 board/raspberrypi/rpi/lowlevel_init.S - -diff --git a/board/raspberrypi/rpi/Makefile b/board/raspberrypi/rpi/Makefile -index 4ce2c98..dcb25ac 100644 ---- a/board/raspberrypi/rpi/Makefile -+++ b/board/raspberrypi/rpi/Makefile -@@ -5,3 +5,4 @@ - # - - obj-y := rpi.o -+obj-y += lowlevel_init.o -diff --git a/board/raspberrypi/rpi/lowlevel_init.S b/board/raspberrypi/rpi/lowlevel_init.S -new file mode 100644 -index 0000000..cdbd8e1 ---- /dev/null -+++ b/board/raspberrypi/rpi/lowlevel_init.S -@@ -0,0 +1,36 @@ -+/* -+ * (C) Copyright 2016 -+ * Cédric Schieli <cschieli@gmail.com> -+ * -+ * SPDX-License-Identifier: GPL-2.0+ -+ */ -+ -+#include <config.h> -+ -+.align 8 -+.global fw_dtb_pointer -+fw_dtb_pointer: -+#ifdef CONFIG_ARM64 -+ .dword 0x0 -+#else -+ .word 0x0 -+#endif -+ -+/* -+ * Routine: save_boot_params (called after reset from start.S) -+ * Description: save ATAG/FDT address provided by the firmware at boot time -+ */ -+ -+.global save_boot_params -+save_boot_params: -+ -+ /* The firmware provided ATAG/FDT address can be found in r2/x0 */ -+#ifdef CONFIG_ARM64 -+ adr x8, fw_dtb_pointer -+ str x0, [x8] -+#else -+ str r2, fw_dtb_pointer -+#endif -+ -+ /* Returns */ -+ b save_boot_params_ret -diff --git a/board/raspberrypi/rpi/rpi.c b/board/raspberrypi/rpi/rpi.c -index 6245b36..ffd6d31 100644 ---- a/board/raspberrypi/rpi/rpi.c -+++ b/board/raspberrypi/rpi/rpi.c -@@ -25,6 +25,9 @@ - - DECLARE_GLOBAL_DATA_PTR; - -+/* From lowlevel_init.S */ -+extern unsigned long fw_dtb_pointer; -+ - static const struct bcm2835_gpio_platdata gpio_platdata = { - .base = BCM2835_GPIO_BASE, - }; -@@ -285,6 +288,31 @@ static void set_fdtfile(void) - setenv("fdtfile", fdtfile); - } - -+/* -+ * If the firmware provided a valid FDT at boot time, let's expose it in -+ * ${fdt_addr} so it may be passed unmodified to the kernel. -+ */ -+static void set_fdt_addr(void) -+{ -+ if (getenv("fdt_addr")) -+ return; -+ -+ if (fdt_magic(fw_dtb_pointer) != FDT_MAGIC) -+ return; -+ -+ setenv_hex("fdt_addr", fw_dtb_pointer); -+} -+ -+/* -+ * Prevent relocation from stomping on a firmware provided FDT blob. -+ */ -+unsigned long board_get_usable_ram_top(unsigned long total_size) -+{ -+ if ((gd->ram_top - fw_dtb_pointer) > SZ_64M) -+ return gd->ram_top; -+ return fw_dtb_pointer & ~0xffff; -+} -+ - static void set_usbethaddr(void) - { - ALLOC_CACHE_ALIGN_BUFFER(struct msg_get_mac_address, msg, 1); -@@ -356,6 +384,7 @@ static void set_serial_number(void) - - int misc_init_r(void) - { -+ set_fdt_addr(); - set_fdtfile(); - set_usbethaddr(); - #ifdef CONFIG_ENV_VARS_UBOOT_RUNTIME_CONFIG --- -2.10.2 - |