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author | Nandor Han <nandor.han@vaisala.com> | 2021-06-10 16:56:45 +0300 |
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committer | Tom Rini <trini@konsulko.com> | 2021-07-23 10:16:39 -0400 |
commit | c74675bd904b6ce9d5820a80f27793c0583fd54c (patch) | |
tree | b9b6e93ebe0d54334e3bf96b70e6a556a01a0f7c /drivers | |
parent | f9db2f16cb6fc7b6d05b0e70de65881bc97ba5c2 (diff) | |
download | u-boot-c74675bd904b6ce9d5820a80f27793c0583fd54c.zip u-boot-c74675bd904b6ce9d5820a80f27793c0583fd54c.tar.gz u-boot-c74675bd904b6ce9d5820a80f27793c0583fd54c.tar.bz2 |
reboot-mode: read the boot mode from RTC memory
RTC devices could provide battery-backed memory that can be used for
storing the reboot mode magic value.
Add a new reboot-mode back-end that uses RTC to store the reboot-mode
magic value. The driver also supports both endianness modes.
Signed-off-by: Nandor Han <nandor.han@vaisala.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/reboot-mode/Kconfig | 9 | ||||
-rw-r--r-- | drivers/reboot-mode/Makefile | 1 | ||||
-rw-r--r-- | drivers/reboot-mode/reboot-mode-rtc.c | 127 |
3 files changed, 137 insertions, 0 deletions
diff --git a/drivers/reboot-mode/Kconfig b/drivers/reboot-mode/Kconfig index ff65e20..ac67bfc 100644 --- a/drivers/reboot-mode/Kconfig +++ b/drivers/reboot-mode/Kconfig @@ -24,4 +24,13 @@ config DM_REBOOT_MODE_GPIO a device in a specific mode by using a GPIO that can be controlled outside U-Boot. +config DM_REBOOT_MODE_RTC + bool "Use RTC as reboot mode backend" + depends on DM_REBOOT_MODE + default n + help + Use RTC non volatile memory to control the reboot mode. This will allow users to boot + a device in a specific mode by using a register(s) that can be controlled + outside U-Boot (e.g. Kernel). + endmenu diff --git a/drivers/reboot-mode/Makefile b/drivers/reboot-mode/Makefile index 04917be..2c13780 100644 --- a/drivers/reboot-mode/Makefile +++ b/drivers/reboot-mode/Makefile @@ -6,3 +6,4 @@ obj-$(CONFIG_DM_REBOOT_MODE) += reboot-mode-uclass.o obj-$(CONFIG_DM_REBOOT_MODE_GPIO) += reboot-mode-gpio.o +obj-$(CONFIG_DM_REBOOT_MODE_RTC) += reboot-mode-rtc.o diff --git a/drivers/reboot-mode/reboot-mode-rtc.c b/drivers/reboot-mode/reboot-mode-rtc.c new file mode 100644 index 0000000..972d0cd --- /dev/null +++ b/drivers/reboot-mode/reboot-mode-rtc.c @@ -0,0 +1,127 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright (c), Vaisala Oyj + */ + +#include <common.h> +#include <dm.h> +#include <dm/device_compat.h> +#include <reboot-mode/reboot-mode-rtc.h> +#include <reboot-mode/reboot-mode.h> +#include <rtc.h> + +DECLARE_GLOBAL_DATA_PTR; + +static int reboot_mode_get(struct udevice *dev, u32 *buf) +{ + if (!buf) + return -EINVAL; + + int ret; + u8 *val = (u8 *)buf; + struct reboot_mode_rtc_platdata *plat_data; + + plat_data = dev_get_plat(dev); + if (!plat_data) + return -EINVAL; + + for (int i = 0; i < plat_data->size; i++) { + ret = rtc_read8(plat_data->rtc, plat_data->addr + i); + if (ret < 0) + return ret; + + val[i] = ret; + } + + if (plat_data->is_big_endian) + *buf = __be32_to_cpu(*buf); + else + *buf = __le32_to_cpu(*buf); + + return 0; +} + +static int reboot_mode_set(struct udevice *dev, u32 buf) +{ + int ret; + u8 *val; + struct reboot_mode_rtc_platdata *plat_data; + + plat_data = dev_get_plat(dev); + if (!plat_data) + return -EINVAL; + + if (plat_data->is_big_endian) + buf = __cpu_to_be32(buf); + else + buf = __cpu_to_le32(buf); + + val = (u8 *)&buf; + + for (int i = 0; i < plat_data->size; i++) { + ret = rtc_write8(plat_data->rtc, (plat_data->addr + i), val[i]); + if (ret < 0) + return ret; + } + + return 0; +} + +#if CONFIG_IS_ENABLED(OF_CONTROL) +static int reboot_mode_ofdata_to_platdata(struct udevice *dev) +{ + struct ofnode_phandle_args phandle_args; + struct reboot_mode_rtc_platdata *plat_data; + + plat_data = dev_get_plat(dev); + if (!plat_data) + return -EINVAL; + + if (dev_read_phandle_with_args(dev, "rtc", NULL, 0, 0, &phandle_args)) { + dev_err(dev, "RTC device not specified\n"); + return -ENOENT; + } + + if (uclass_get_device_by_ofnode(UCLASS_RTC, phandle_args.node, + &plat_data->rtc)) { + dev_err(dev, "could not get the RTC device\n"); + return -ENODEV; + } + + plat_data->addr = + dev_read_addr_size_index(dev, 0, (fdt_size_t *)&plat_data->size); + if (plat_data->addr == FDT_ADDR_T_NONE) { + dev_err(dev, "Invalid RTC address\n"); + return -EINVAL; + } + if (plat_data->size > sizeof(u32)) { + dev_err(dev, "Invalid reg size\n"); + return -EINVAL; + } + + plat_data->is_big_endian = ofnode_read_bool(dev_ofnode(dev), "big-endian"); + + return 0; +} + +static const struct udevice_id reboot_mode_ids[] = { + { .compatible = "reboot-mode-rtc", 0 }, + {} +}; +#endif + +static const struct reboot_mode_ops reboot_mode_rtc_ops = { + .get = reboot_mode_get, + .set = reboot_mode_set, +}; + +U_BOOT_DRIVER(reboot_mode_rtc) = { + .name = "reboot-mode-rtc", + .id = UCLASS_REBOOT_MODE, +#if CONFIG_IS_ENABLED(OF_CONTROL) + .of_match = reboot_mode_ids, + .of_to_plat = reboot_mode_ofdata_to_platdata, +#endif + .plat_auto = sizeof(struct reboot_mode_rtc_platdata), + .ops = &reboot_mode_rtc_ops, +}; |