Re: [PATCH] ARM: rockchip: add reboot notifier

[Alexey Klimov <klimov.linux@gmail.com>]

Hi Andy,

On Tue, Sep 8, 2015 at 3:43 PM, Andy Yan <andy.yan@rock-chips.com> wrote:
> rockchip platform have a protocol to pass the the kernel

Double 'the'?

> reboot mode to bootloader by some special registers when
> system reboot. By this way the bootloader can take different
> action according to the different kernel reboot mode, for
> example, command "reboot loader" will reboot the board to
> rockusb mode, this is a very convenient way to get the board
> to download mode.
>
> Signed-off-by: Andy Yan <andy.yan@rock-chips.com>
> ---
>
>  arch/arm/mach-rockchip/Makefile |   2 +-
>  arch/arm/mach-rockchip/loader.h |  22 +++++++++
>  arch/arm/mach-rockchip/reboot.c | 103 ++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 126 insertions(+), 1 deletion(-)
>  create mode 100644 arch/arm/mach-rockchip/loader.h
>  create mode 100644 arch/arm/mach-rockchip/reboot.c
>
> diff --git a/arch/arm/mach-rockchip/Makefile b/arch/arm/mach-rockchip/Makefile
> index 5c3a9b2..cd291e3 100644
> --- a/arch/arm/mach-rockchip/Makefile
> +++ b/arch/arm/mach-rockchip/Makefile
> @@ -1,5 +1,5 @@
>  CFLAGS_platsmp.o := -march=armv7-a
>
> -obj-$(CONFIG_ARCH_ROCKCHIP) += rockchip.o
> +obj-$(CONFIG_ARCH_ROCKCHIP) += rockchip.o reboot.o
>  obj-$(CONFIG_PM_SLEEP) += pm.o sleep.o
>  obj-$(CONFIG_SMP) += headsmp.o platsmp.o
> diff --git a/arch/arm/mach-rockchip/loader.h b/arch/arm/mach-rockchip/loader.h
> new file mode 100644
> index 0000000..bf51baa
> --- /dev/null
> +++ b/arch/arm/mach-rockchip/loader.h
> @@ -0,0 +1,22 @@
> +#ifndef __MACH_ROCKCHIP_LOADER_H
> +#define __MACH_ROCKCHIP_LOADER_H
> +
> +/*high 24 bits is tag, low 8 bits is type*/
> +#define SYS_LOADER_REBOOT_FLAG   0x5242C300
> +
> +enum {
> +       BOOT_NORMAL = 0, /* normal boot */
> +       BOOT_LOADER,     /* enter loader rockusb mode */
> +       BOOT_MASKROM,    /* enter maskrom rockusb mode (not support now) */
> +       BOOT_RECOVER,    /* enter recover */
> +       BOOT_NORECOVER,  /* do not enter recover */
> +       BOOT_SECONDOS,   /* boot second OS (not support now)*/
> +       BOOT_WIPEDATA,   /* enter recover and wipe data. */
> +       BOOT_WIPEALL,    /* enter recover and wipe all data. */
> +       BOOT_CHECKIMG,   /* check firmware img with backup part*/
> +       BOOT_FASTBOOT,   /* enter fast boot mode */
> +       BOOT_SECUREBOOT_DISABLE,
> +       BOOT_CHARGING,   /* enter charge mode */
> +       BOOT_MAX         /* MAX VALID BOOT TYPE.*/

Looks like you only implemented NORMAL, RECOVER, LOADER and CHARGING.
Are you keeping other entries for keeping right order and keep
consistency?
Or have plans for future?

> +};
> +#endif
> diff --git a/arch/arm/mach-rockchip/reboot.c b/arch/arm/mach-rockchip/reboot.c
> new file mode 100644
> index 0000000..704bc16
> --- /dev/null
> +++ b/arch/arm/mach-rockchip/reboot.c
> @@ -0,0 +1,103 @@
> +#include <linux/init.h>

Usually people place in the beginning copyright and GPL license header info.

> +#include <linux/module.h>
> +#include <linux/kernel.h>
> +#include <linux/of.h>
> +#include <linux/of_address.h>
> +#include <linux/reboot.h>
> +#include <linux/regmap.h>
> +#include <linux/mfd/syscon.h>
> +#include "loader.h"
> +
> +#define RK3188_PMU_SYS_REG0             0x40
> +#define RK3288_PMU_SYS_REG0             0x94
> +
> +struct regmap *regmap;
> +int flag_reg;
> +
> +static int rockchip_get_pmu_regmap(void)
> +{
> +       struct device_node *node;
> +
> +       node = of_find_node_by_path("/cpus");

Is it critical not to check node for NULL here?

> +       regmap = syscon_regmap_lookup_by_phandle(node, "rockchip,pmu");
> +       of_node_put(node);
> +       if (!IS_ERR(regmap))
> +               return 0;
> +
> +       regmap = syscon_regmap_lookup_by_compatible("rockchip,rk3066-pmu");
> +       of_node_put(node);
> +       if (!IS_ERR(regmap))
> +               return 0;
> +
> +       return -ENODEV;
> +}

This double of_node_put(node) confuses me. Could you please guide me over it?

After I tried to re-create it by myself looking to code I think that
second of_node_put() is not needed.

> +static int rockchip_get_reboot_flag_regmap(void)
> +{
> +       int ret = rockchip_get_pmu_regmap();
> +
> +       if (ret < 0)
> +               return ret;
> +
> +       if (of_machine_is_compatible("rockchip,rk3288")) {
> +               flag_reg = RK3288_PMU_SYS_REG0;
> +               return 0;
> +       } else if (of_machine_is_compatible("rockchip,rk3066a") ||
> +                  of_machine_is_compatible("rockchip,rk3066b") ||
> +                  of_machine_is_compatible("rockchip,rk3188")) {
> +               flag_reg = RK3188_PMU_SYS_REG0;
> +               return 0;
> +       }
> +
> +       return -ENODEV;

[..]

> +
> +static int __init rockchip_reboot_init(void)
> +{
> +       int ret = 0;
> +
> +       if (!rockchip_get_reboot_flag_regmap()) {
> +               ret = register_restart_handler(&rockchip_reboot_handler);
> +               if (ret)
> +                       pr_err("%s: cannot register reboot handler, %d\n",
> +                              __func__, ret);
> +       }
> +
> +return ret;

Please align this correctly.

Thanks,
Alexey Klimov