mail archive of the barebox mailing list
 help / color / mirror / Atom feed
From: Sascha Hauer <s.hauer@pengutronix.de>
To: Juergen Borleis <jbe@pengutronix.de>
Cc: barebox@lists.infradead.org
Subject: Re: [PATCH 2/5] System restart: add a scope value to the system restart feature
Date: Wed, 24 Jun 2015 08:42:08 +0200	[thread overview]
Message-ID: <20150624064208.GS6325@pengutronix.de> (raw)
In-Reply-To: <1435064284-8015-3-git-send-email-jbe@pengutronix.de>

On Tue, Jun 23, 2015 at 02:58:01PM +0200, Juergen Borleis wrote:
> Some systems have more than one feature to restart it. Maybe these restarts
> features are all equal or it is very important which restart feauture is used
> to restart the system in a reliable manner. For example if external
> devices must be reset in conjunction with the SoC some SoC's internal
> restart features cannot be used. Then an external restart feature must
> be forced instead by using the restart feature with the wider scope.
> 
> Signed-off-by: Juergen Borleis <jbe@pengutronix.de>
> ---
>  Documentation/user/system-reset.rst              | 41 ++++++++++++++++++
>  arch/arm/lib/bootm.c                             |  7 +--
>  arch/arm/mach-at91/at91rm9200_time.c             | 12 ++++--
>  arch/arm/mach-bcm2835/core.c                     | 21 ++++-----
>  arch/arm/mach-clps711x/reset.c                   | 10 ++++-
>  arch/arm/mach-davinci/time.c                     | 12 ++++--
>  arch/arm/mach-digic/core.c                       | 25 -----------
>  arch/arm/mach-ep93xx/clocksource.c               | 17 +++++---
>  arch/arm/mach-highbank/reset.c                   | 12 +++++-
>  arch/arm/mach-mvebu/armada-370-xp.c              |  9 ++--
>  arch/arm/mach-mvebu/common.c                     | 13 ------
>  arch/arm/mach-mvebu/dove.c                       |  9 ++--
>  arch/arm/mach-mvebu/include/mach/common.h        |  1 -
>  arch/arm/mach-mvebu/kirkwood.c                   |  9 ++--
>  arch/arm/mach-mxs/soc-imx23.c                    |  8 ++--
>  arch/arm/mach-mxs/soc-imx28.c                    | 13 ++++--
>  arch/arm/mach-netx/generic.c                     | 11 ++++-
>  arch/arm/mach-nomadik/reset.c                    | 13 ++++--
>  arch/arm/mach-omap/am33xx_generic.c              |  4 +-
>  arch/arm/mach-omap/include/mach/am33xx-generic.h |  2 +-
>  arch/arm/mach-omap/include/mach/omap3-generic.h  |  2 +-
>  arch/arm/mach-omap/include/mach/omap4-generic.h  |  2 +-
>  arch/arm/mach-omap/omap3_generic.c               |  5 +--
>  arch/arm/mach-omap/omap4_generic.c               |  4 +-
>  arch/arm/mach-omap/omap_generic.c                | 12 +++---
>  arch/arm/mach-pxa/common.c                       | 12 +++++-
>  arch/arm/mach-rockchip/core.c                    | 14 ++++--
>  arch/arm/mach-samsung/generic.c                  | 13 ++++--
>  arch/arm/mach-socfpga/reset-manager.c            | 12 +++++-
>  arch/arm/mach-tegra/tegra20-pmc.c                |  6 +--
>  arch/arm/mach-uemd/reset.c                       | 24 -----------
>  arch/arm/mach-versatile/core.c                   |  7 +--
>  arch/arm/mach-vexpress/reset.c                   | 13 ++++--
>  arch/arm/mach-zynq/zynq.c                        | 12 ++++--
>  arch/blackfin/lib/cpu.c                          | 11 ++++-
>  arch/efi/efi/efi.c                               | 11 ++++-
>  arch/mips/mach-ar231x/ar231x_reset.c             |  8 ++--
>  arch/mips/mach-ath79/reset.c                     | 13 ++++--
>  arch/mips/mach-bcm47xx/reset.c                   | 14 ++++--
>  arch/mips/mach-loongson/loongson1_reset.c        | 13 ++++--
>  arch/mips/mach-malta/reset.c                     | 14 ++++--
>  arch/nios2/cpu/cpu.c                             | 12 +++++-
>  arch/openrisc/cpu/cpu.c                          | 11 ++++-
>  arch/ppc/mach-mpc5xxx/cpu.c                      | 11 ++++-
>  arch/ppc/mach-mpc85xx/cpu.c                      | 12 ++++--
>  arch/sandbox/os/common.c                         | 10 ++++-
>  arch/x86/mach-i386/reset.c                       | 30 -------------
>  commands/reset.c                                 |  3 +-
>  common/misc.c                                    |  3 +-
>  common/restart.c                                 | 55 ++++++++++++++++++++++++
>  drivers/usb/gadget/f_fastboot.c                  |  3 +-
>  drivers/watchdog/imxwd.c                         | 21 ++++-----
>  drivers/watchdog/jz4740.c                        | 33 ++++++--------
>  include/common.h                                 |  1 -
>  include/restart.h                                |  6 +++
>  55 files changed, 432 insertions(+), 250 deletions(-)
>  delete mode 100644 arch/arm/mach-digic/core.c
>  delete mode 100644 arch/arm/mach-uemd/reset.c
>  delete mode 100644 arch/x86/mach-i386/reset.c
> 
> diff --git a/Documentation/user/system-reset.rst b/Documentation/user/system-reset.rst
> index e902026..6770371 100644
> --- a/Documentation/user/system-reset.rst
> +++ b/Documentation/user/system-reset.rst
> @@ -3,6 +3,11 @@
>  System Restart
>  --------------
>  
> +.. _system_reset_pitfalls:
> +
> +Common Pitfalls
> +~~~~~~~~~~~~~~~
> +
>  When running the reset command barebox restarts the SoC somehow. Restart can
>  be done in software, but a more reliable way is to use a hard reset line, which
>  really resets the whole machine.
> @@ -63,3 +68,39 @@ detect the :ref:`reset_reason` anymore. From the SoC point of view it is always
>  a POR when the PMIC handles the system reset. If you are in luck the PMIC
>  instead can provide this information if you depend on it. Refer
>  :ref:`reset_reason_scope` for further information.
> +
> +Handling the system restart from the developers point of view
> +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> +
> +Sometimes more than one system restart feature is available on a machine and
> +due to 'some reasons' all these unit's drivers must be enabled at run-time
> +(maybe they are MFDs (e.g. multi function devices) or you want to run one
> +binary barebox on more than one machine). In such a case more than one driver
> +registers its system reset feature at run-time. So a mechanism is required
> +in order to let barebox selects the 'correct' one to trigger a system restart.
> +
> +Barebox can handle and use one system restart feature only. If the available
> +system restart features are equivalent it doesn't matter which one barebox
> +selects to trigger a system restart. But if your machine depends on a specific
> +system restart feature you must ensure it will be used all the time to get a
> +reliable system restart.
> +
> +To handle this, registering system restart features are handled by their scope.
> +Due to the listed issues in :ref:`system_reset_pitfalls` all the (mostly) built-in
> +watchdog units will register their system restart feature with a limited scope.
> +And will still be used by barebox to restart the system if no alternative is
> +available.
> +If your machine has special requirements to restart the system and a more reliable
> +system restart feature is on hand it must register its system restart feature
> +with a wider scope. Barebox will then prefer the wider scope feature to restart
> +the system.
> +
> +Here the list of defined scopes (defined in file ``include/restart.h``):
> +
> +* ``FEATURE_SCOPE_UNKNOWN``: last resort to restart a machine and might be used
> +  as a fall-back only.
> +* ``FEATURE_SCOPE_CPU``: this restart feature is able to restart the core CPU only.
> +* ``FEATURE_SCOPE_SOC``: this restart feature is able to restart the whole SoC,
> +  including the core CPU.
> +* ``FEATURE_SCOPE_MACHINE``: this restart feature is able to restart the whole machine,
> +  including the SoC and the core CPU.
> diff --git a/arch/arm/lib/bootm.c b/arch/arm/lib/bootm.c
> index 8327c3f..7bb9b43 100644
> --- a/arch/arm/lib/bootm.c
> +++ b/arch/arm/lib/bootm.c
> @@ -16,6 +16,7 @@
>  #include <libbb.h>
>  #include <magicvar.h>
>  #include <binfmt.h>
> +#include <restart.h>
>  
>  #include <asm/byteorder.h>
>  #include <asm/setup.h>
> @@ -111,7 +112,7 @@ static int __do_bootm_linux(struct image_data *data, unsigned long free_mem, int
>  
>  	start_linux((void *)kernel, swap, initrd_start, initrd_size, data->oftree);
>  
> -	reset_cpu(0);
> +	restart_machine();
>  
>  	return -ERESTARTSYS;
>  }
> @@ -378,7 +379,7 @@ static int do_bootm_barebox(struct image_data *data)
>  
>  	start_linux(barebox, 0, 0, 0, data->oftree);
>  
> -	reset_cpu(0);
> +	restart_machine();
>  }
>  
>  static struct image_handler barebox_handler = {
> @@ -518,7 +519,7 @@ static int do_bootm_aimage(struct image_data *data)
>  
>  		second();
>  
> -		reset_cpu(0);
> +		restart_machine();
>  	}
>  
>  	close(fd);
> diff --git a/arch/arm/mach-at91/at91rm9200_time.c b/arch/arm/mach-at91/at91rm9200_time.c
> index ae0172b..c017ad8 100644
> --- a/arch/arm/mach-at91/at91rm9200_time.c
> +++ b/arch/arm/mach-at91/at91rm9200_time.c
> @@ -28,6 +28,7 @@
>  #include <common.h>
>  #include <init.h>
>  #include <clock.h>
> +#include <restart.h>
>  #include <mach/hardware.h>
>  #include <mach/at91_tc.h>
>  #include <mach/at91_st.h>
> @@ -77,7 +78,7 @@ core_initcall(clocksource_init);
>  /*
>   * Reset the cpu through the reset controller
>   */
> -void __noreturn reset_cpu (unsigned long ignored)
> +static void __noreturn at91rm9200_restart_soc(struct device_d *dev)
>  {
>  	/*
>  	 * Perform a hardware reset with the use of the Watchdog timer.
> @@ -86,6 +87,11 @@ void __noreturn reset_cpu (unsigned long ignored)
>  	at91_sys_write(AT91_ST_CR, AT91_ST_WDRST);
>  
>  	/* Not reached */
> -	while (1);
> +	hang();
>  }
> -EXPORT_SYMBOL(reset_cpu);
> +
> +static int restart_register_feature(void)
> +{
> +	restart_register_handler(at91rm9200_restart_soc, NULL, FEATURE_SCOPE_SOC);
> +}
> +coredevice_initcall(restart_register_feature);
> diff --git a/arch/arm/mach-bcm2835/core.c b/arch/arm/mach-bcm2835/core.c
> index 5d08012..6f6ae8a 100644
> --- a/arch/arm/mach-bcm2835/core.c
> +++ b/arch/arm/mach-bcm2835/core.c
> @@ -18,6 +18,7 @@
>  
>  #include <common.h>
>  #include <init.h>
> +#include <restart.h>
>  
>  #include <linux/clk.h>
>  #include <linux/clkdev.h>
> @@ -51,13 +52,6 @@ static int bcm2835_clk_init(void)
>  }
>  postcore_initcall(bcm2835_clk_init);
>  
> -static int bcm2835_dev_init(void)
> -{
> -	add_generic_device("bcm2835-gpio", 0, NULL, BCM2835_GPIO_BASE, 0xB0, IORESOURCE_MEM, NULL);
> -	return 0;
> -}
> -coredevice_initcall(bcm2835_dev_init);
> -
>  void bcm2835_register_uart(void)
>  {
>  	amba_apb_device_add(NULL, "uart0-pl011", 0, BCM2835_UART0_BASE, 4096, NULL, 0);
> @@ -72,7 +66,7 @@ void bcm2835_add_device_sdram(u32 size)
>  }
>  #define RESET_TIMEOUT 10
>  
> -void __noreturn reset_cpu(unsigned long addr)
> +static void __noreturn bcm2835_restart_soc(struct device_d *dev)
>  {
>  	uint32_t rstc;
>  
> @@ -82,6 +76,13 @@ void __noreturn reset_cpu(unsigned long addr)
>  	writel(PM_PASSWORD | RESET_TIMEOUT, PM_WDOG);
>  	writel(PM_PASSWORD | rstc, PM_RSTC);
>  
> -	while (1);
> +	hang();
>  }
> -EXPORT_SYMBOL(reset_cpu);
> +
> +static int bcm2835_dev_init(void)
> +{
> +	add_generic_device("bcm2835-gpio", 0, NULL, BCM2835_GPIO_BASE, 0xB0, IORESOURCE_MEM, NULL);
> +	restart_register_handler(bcm2835_restart_soc, NULL, FEATURE_SCOPE_SOC);
> +	return 0;
> +}
> +coredevice_initcall(bcm2835_dev_init);
> diff --git a/arch/arm/mach-clps711x/reset.c b/arch/arm/mach-clps711x/reset.c
> index 67c9c8b..225ef15 100644
> --- a/arch/arm/mach-clps711x/reset.c
> +++ b/arch/arm/mach-clps711x/reset.c
> @@ -8,8 +8,10 @@
>   */
>  
>  #include <common.h>
> +#include <init.h>
> +#include <restart.h>
>  
> -void __noreturn reset_cpu(unsigned long addr)
> +static void __noreturn clps711x_restart_soc(struct device_d *dev)
>  {
>  	arch_shutdown();
>  
> @@ -17,3 +19,9 @@ void __noreturn reset_cpu(unsigned long addr)
>  
>  	hang();
>  }
> +
> +static int restart_register_feature(void)
> +{
> +	restart_register_handler(clps711x_restart_soc, NULL, FEATURE_SCOPE_SOC);
> +}
> +coredevice_initcall(restart_register_feature);
> diff --git a/arch/arm/mach-davinci/time.c b/arch/arm/mach-davinci/time.c
> index 60f0d19..8b53879 100644
> --- a/arch/arm/mach-davinci/time.c
> +++ b/arch/arm/mach-davinci/time.c
> @@ -12,6 +12,7 @@
>  #include <common.h>
>  #include <io.h>
>  #include <init.h>
> +#include <restart.h>
>  #include <clock.h>
>  
>  #include <mach/time.h>
> @@ -164,7 +165,7 @@ static int clocksource_init(void)
>  core_initcall(clocksource_init);
>  
>  /* reset board using watchdog timer */
> -void __noreturn reset_cpu(ulong addr)
> +static void __noreturn davinci_restart_soc(struct device_d *dev)
>  {
>  	u32 tgcr, wdtcr;
>  	void __iomem *base;
> @@ -204,6 +205,11 @@ void __noreturn reset_cpu(ulong addr)
>  	wdtcr = 0x00004000;
>  	__raw_writel(wdtcr, base + WDTCR);
>  
> -	unreachable();
> +	hang();
>  }
> -EXPORT_SYMBOL(reset_cpu);
> +
> +static int restart_register_feature(void)
> +{
> +	restart_register_handler(davinci_restart_soc, NULL, FEATURE_SCOPE_SOC);
> +}
> +coredevice_initcall(restart_register_feature);
> diff --git a/arch/arm/mach-digic/core.c b/arch/arm/mach-digic/core.c
> deleted file mode 100644
> index b1caec0..0000000
> --- a/arch/arm/mach-digic/core.c
> +++ /dev/null
> @@ -1,25 +0,0 @@
> -/*
> - * Copyright (C) 2013 Antony Pavlov <antonynpavlov@gmail.com>
> - *
> - * This file is part of barebox.
> - * See file CREDITS for list of people who contributed to this project.
> - *
> - * This program is free software; you can redistribute it and/or modify
> - * it under the terms of the GNU General Public License version 2
> - * as published by the Free Software Foundation.
> - *
> - * 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.
> - *
> - */
> -
> -#include <common.h>
> -
> -void __noreturn reset_cpu(unsigned long ignored)
> -{
> -	pr_err("%s: unimplemented\n", __func__);
> -	hang();
> -}
> -EXPORT_SYMBOL(reset_cpu);
> diff --git a/arch/arm/mach-ep93xx/clocksource.c b/arch/arm/mach-ep93xx/clocksource.c
> index f396d0a..c811641 100644
> --- a/arch/arm/mach-ep93xx/clocksource.c
> +++ b/arch/arm/mach-ep93xx/clocksource.c
> @@ -20,6 +20,7 @@
>  #include <init.h>
>  #include <clock.h>
>  #include <io.h>
> +#include <restart.h>
>  #include <mach/ep93xx-regs.h>
>  
>  #define TIMER_CLKSEL		(1 << 3)
> @@ -63,10 +64,8 @@ static int clocksource_init(void)
>  
>  core_initcall(clocksource_init);
>  
> -/*
> - * Reset the cpu
> - */
> -void __noreturn reset_cpu(unsigned long addr)
> +/* Reset the SoC */
> +static void __noreturn ep92xx_restart_soc(struct device_d *dev)
>  {
>  	struct syscon_regs *syscon = (struct syscon_regs *)SYSCON_BASE;
>  	uint32_t value;
> @@ -84,7 +83,11 @@ void __noreturn reset_cpu(unsigned long addr)
>  	writel(value, &syscon->devicecfg);
>  
>  	/* Dying... */
> -	while (1)
> -		; /* noop */
> +	hang();
> +}
> +
> +static int restart_register_feature(void)
> +{
> +	restart_register_handler(ep92xx_restart_soc, NULL, FEATURE_SCOPE_SOC);
>  }
> -EXPORT_SYMBOL(reset_cpu);
> +coredevice_initcall(restart_register_feature);
> diff --git a/arch/arm/mach-highbank/reset.c b/arch/arm/mach-highbank/reset.c
> index b9664e4..cff5cae 100644
> --- a/arch/arm/mach-highbank/reset.c
> +++ b/arch/arm/mach-highbank/reset.c
> @@ -6,17 +6,25 @@
>  
>  #include <common.h>
>  #include <io.h>
> +#include <restart.h>
> +#include <init.h>
>  
>  #include <mach/devices.h>
>  #include <mach/sysregs.h>
>  
> -void __noreturn reset_cpu(ulong addr)
> +static void __noreturn highbank_restart_soc(struct device_d *dev)
>  {
>  	hingbank_set_pwr_hard_reset();
>  	asm("	wfi");
>  
> -	while(1);
> +	hang();
> +}
> +
> +static int restart_register_feature(void)
> +{
> +	restart_register_handler(highbank_restart_soc, NULL, FEATURE_SCOPE_SOC);
>  }
> +coredevice_initcall(restart_register_feature);
>  
>  void __noreturn poweroff()
>  {
> diff --git a/arch/arm/mach-mvebu/armada-370-xp.c b/arch/arm/mach-mvebu/armada-370-xp.c
> index 2405629..0c52523 100644
> --- a/arch/arm/mach-mvebu/armada-370-xp.c
> +++ b/arch/arm/mach-mvebu/armada-370-xp.c
> @@ -17,6 +17,7 @@
>  #include <common.h>
>  #include <init.h>
>  #include <io.h>
> +#include <restart.h>
>  #include <of.h>
>  #include <of_address.h>
>  #include <asm/memory.h>
> @@ -104,12 +105,12 @@ static int armada_370_xp_soc_id_fixup(void)
>  	return 0;
>  }
>  
> -static void __noreturn armada_370_xp_reset_cpu(unsigned long addr)
> +static void __noreturn armada_370_xp_restart_soc(struct device_d *dev)
>  {
>  	writel(0x1, ARMADA_370_XP_SYSCTL_BASE + 0x60);
>  	writel(0x1, ARMADA_370_XP_SYSCTL_BASE + 0x64);
> -	while (1)
> -		;
> +
> +	hang();
>  }
>  
>  static int armada_xp_init_soc(struct device_node *root)
> @@ -132,7 +133,7 @@ static int armada_370_xp_init_soc(struct device_node *root, void *context)
>  	if (!of_machine_is_compatible("marvell,armada-370-xp"))
>  		return 0;
>  
> -	mvebu_set_reset(armada_370_xp_reset_cpu);
> +	restart_register_handler(armada_370_xp_restart_soc, NULL, FEATURE_SCOPE_SOC);
>  
>  	barebox_set_model("Marvell Armada 370/XP");
>  	barebox_set_hostname("armada");
> diff --git a/arch/arm/mach-mvebu/common.c b/arch/arm/mach-mvebu/common.c
> index 7d28d9c..cb40d0c 100644
> --- a/arch/arm/mach-mvebu/common.c
> +++ b/arch/arm/mach-mvebu/common.c
> @@ -123,16 +123,3 @@ int mvebu_set_memory(u64 phys_base, u64 phys_size)
>  
>  	return 0;
>  }
> -
> -static __noreturn void (*mvebu_reset_cpu)(unsigned long addr);
> -
> -void __noreturn reset_cpu(unsigned long addr)
> -{
> -	mvebu_reset_cpu(addr);
> -}
> -EXPORT_SYMBOL(reset_cpu);
> -
> -void mvebu_set_reset(void __noreturn (*reset)(unsigned long addr))
> -{
> -	mvebu_reset_cpu = reset;
> -}
> diff --git a/arch/arm/mach-mvebu/dove.c b/arch/arm/mach-mvebu/dove.c
> index a7284fd..b727215 100644
> --- a/arch/arm/mach-mvebu/dove.c
> +++ b/arch/arm/mach-mvebu/dove.c
> @@ -17,6 +17,7 @@
>  #include <common.h>
>  #include <init.h>
>  #include <io.h>
> +#include <restart.h>
>  #include <asm/memory.h>
>  #include <linux/mbus.h>
>  #include <mach/dove-regs.h>
> @@ -68,13 +69,13 @@ static inline void dove_memory_find(unsigned long *phys_base,
>  	}
>  }
>  
> -static void __noreturn dove_reset_cpu(unsigned long addr)
> +static void __noreturn dove_restart_soc(struct device_d *dev)
>  {
>  	/* enable and assert RSTOUTn */
>  	writel(SOFT_RESET_OUT_EN, DOVE_BRIDGE_BASE + BRIDGE_RSTOUT_MASK);
>  	writel(SOFT_RESET_EN, DOVE_BRIDGE_BASE + BRIDGE_SYS_SOFT_RESET);
> -	while (1)
> -		;
> +
> +	hang();
>  }
>  
>  static int dove_init_soc(struct device_node *root, void *context)
> @@ -84,7 +85,7 @@ static int dove_init_soc(struct device_node *root, void *context)
>  	if (!of_machine_is_compatible("marvell,dove"))
>  		return 0;
>  
> -	mvebu_set_reset(dove_reset_cpu);
> +	restart_register_handler(dove_restart_soc, NULL, FEATURE_SCOPE_SOC);
>  
>  	barebox_set_model("Marvell Dove");
>  	barebox_set_hostname("dove");
> diff --git a/arch/arm/mach-mvebu/include/mach/common.h b/arch/arm/mach-mvebu/include/mach/common.h
> index 5ce33fd..602af8f 100644
> --- a/arch/arm/mach-mvebu/include/mach/common.h
> +++ b/arch/arm/mach-mvebu/include/mach/common.h
> @@ -21,6 +21,5 @@
>  #define MVEBU_REMAP_INT_REG_BASE	0xf1000000
>  
>  int mvebu_set_memory(u64 phys_base, u64 phys_size);
> -void mvebu_set_reset(void __noreturn (*reset)(unsigned long addr));
>  
>  #endif
> diff --git a/arch/arm/mach-mvebu/kirkwood.c b/arch/arm/mach-mvebu/kirkwood.c
> index 19c6f07..00e213f 100644
> --- a/arch/arm/mach-mvebu/kirkwood.c
> +++ b/arch/arm/mach-mvebu/kirkwood.c
> @@ -16,6 +16,7 @@
>  #include <common.h>
>  #include <init.h>
>  #include <io.h>
> +#include <restart.h>
>  #include <asm/memory.h>
>  #include <linux/mbus.h>
>  #include <mach/kirkwood-regs.h>
> @@ -43,12 +44,12 @@ static inline void kirkwood_memory_find(unsigned long *phys_base,
>  	}
>  }
>  
> -static void __noreturn kirkwood_reset_cpu(unsigned long addr)
> +static void __noreturn kirkwood_restart_soc(struct device_d *dev)
>  {
>  	writel(SOFT_RESET_OUT_EN, KIRKWOOD_BRIDGE_BASE + BRIDGE_RSTOUT_MASK);
>  	writel(SOFT_RESET_EN, KIRKWOOD_BRIDGE_BASE + BRIDGE_SYS_SOFT_RESET);
> -	for(;;)
> -		;
> +
> +	hang();
>  }
>  
>  static int kirkwood_init_soc(struct device_node *root, void *context)
> @@ -58,7 +59,7 @@ static int kirkwood_init_soc(struct device_node *root, void *context)
>  	if (!of_machine_is_compatible("marvell,kirkwood"))
>  		return 0;
>  
> -	mvebu_set_reset(kirkwood_reset_cpu);
> +	restart_register_handler(kirkwood_restart_soc, NULL, FEATURE_SCOPE_SOC);
>  
>  	barebox_set_model("Marvell Kirkwood");
>  	barebox_set_hostname("kirkwood");
> diff --git a/arch/arm/mach-mxs/soc-imx23.c b/arch/arm/mach-mxs/soc-imx23.c
> index 339c577..fd8cf04 100644
> --- a/arch/arm/mach-mxs/soc-imx23.c
> +++ b/arch/arm/mach-mxs/soc-imx23.c
> @@ -16,6 +16,7 @@
>  
>  #include <common.h>
>  #include <init.h>
> +#include <restart.h>
>  #include <mach/imx23-regs.h>
>  #include <io.h>
>  
> @@ -23,18 +24,16 @@
>  # define HW_CLKCTRL_RESET_CHIP (1 << 1)
>  
>  /* Reset the full i.MX23 SoC via a chipset feature */
> -void __noreturn reset_cpu(unsigned long addr)
> +static void __noreturn imx23_restart_soc(struct device_d *dev)
>  {
>  	u32 reg;
>  
>  	reg = readl(IMX_CCM_BASE + HW_CLKCTRL_RESET);
>  	writel(reg | HW_CLKCTRL_RESET_CHIP, IMX_CCM_BASE + HW_CLKCTRL_RESET);
>  
> -	while (1)
> -		;
> +	hang();
>  	/*NOTREACHED*/
>  }
> -EXPORT_SYMBOL(reset_cpu);
>  
>  static int imx23_devices_init(void)
>  {
> @@ -46,6 +45,7 @@ static int imx23_devices_init(void)
>  	add_generic_device("imx23-gpio", 0, NULL, IMX_IOMUXC_BASE, 0x2000, IORESOURCE_MEM, NULL);
>  	add_generic_device("imx23-gpio", 1, NULL, IMX_IOMUXC_BASE, 0x2000, IORESOURCE_MEM, NULL);
>  	add_generic_device("imx23-gpio", 2, NULL, IMX_IOMUXC_BASE, 0x2000, IORESOURCE_MEM, NULL);
> +	restart_register_handler(imx23_restart_soc, NULL, FEATURE_SCOPE_SOC);
>  
>  	return 0;
>  }
> diff --git a/arch/arm/mach-mxs/soc-imx28.c b/arch/arm/mach-mxs/soc-imx28.c
> index b4ec38d..ed9ae05 100644
> --- a/arch/arm/mach-mxs/soc-imx28.c
> +++ b/arch/arm/mach-mxs/soc-imx28.c
> @@ -16,6 +16,7 @@
>  
>  #include <common.h>
>  #include <init.h>
> +#include <restart.h>
>  #include <mach/imx28-regs.h>
>  #include <io.h>
>  
> @@ -24,18 +25,22 @@
>  #define HW_CLKCTRL_WDOG_POR_DISABLE (1 << 5)
>  
>  /* Reset the full i.MX28 SoC via a chipset feature */
> -void __noreturn reset_cpu(unsigned long addr)
> +static void __noreturn imx28_restart_soc(struct device_d *dev)
>  {
>  	u32 reg;
>  
>  	reg = readl(IMX_CCM_BASE + HW_CLKCTRL_RESET);
>  	writel(reg | HW_CLKCTRL_RESET_CHIP, IMX_CCM_BASE + HW_CLKCTRL_RESET);
>  
> -	while (1)
> -		;
> +	hang();
>  	/*NOTREACHED*/
>  }
> -EXPORT_SYMBOL(reset_cpu);
> +
> +static int restart_register_feature(void)
> +{
> +	restart_register_handler(imx28_restart_soc, NULL, FEATURE_SCOPE_SOC);
> +}
> +coredevice_initcall(restart_register_feature);
>  
>  static int imx28_init(void)
>  {
> diff --git a/arch/arm/mach-netx/generic.c b/arch/arm/mach-netx/generic.c
> index 6127dde..7ae1b4c 100644
> --- a/arch/arm/mach-netx/generic.c
> +++ b/arch/arm/mach-netx/generic.c
> @@ -15,8 +15,10 @@
>   */
>  
>  #include <common.h>
> +#include <init.h>
>  #include <command.h>
>  #include <io.h>
> +#include <restart.h>
>  #include <mach/netx-regs.h>
>  #include "eth_firmware.h"
>  
> @@ -134,14 +136,19 @@ failure:
>  	return COMMAND_ERROR_USAGE;
>  }
>  
> -void __noreturn reset_cpu(unsigned long addr)
> +static void __noreturn netx_restart_soc(struct device_d *dev)
>  {
>  	SYSTEM_REG(SYSTEM_RES_CR) = 0x01000008;
>  
>  	/* Not reached */
> -	while (1);
> +	hang();
>  }
>  
> +static int restart_register_feature(void)
> +{
> +	restart_register_handler(netx_restart_soc, NULL, FEATURE_SCOPE_SOC);
> +}
> +coredevice_initcall(restart_register_feature);
>  
>  BAREBOX_CMD_START(loadxc)
>  	.cmd		= do_loadxc,
> diff --git a/arch/arm/mach-nomadik/reset.c b/arch/arm/mach-nomadik/reset.c
> index bb5696a..fa9f650 100644
> --- a/arch/arm/mach-nomadik/reset.c
> +++ b/arch/arm/mach-nomadik/reset.c
> @@ -15,10 +15,12 @@
>   */
>  
>  #include <common.h>
> +#include <init.h>
>  #include <io.h>
> +#include <restart.h>
>  #include <mach/hardware.h>
>  
> -void __noreturn reset_cpu(unsigned long addr)
> +static void __noreturn nomadik_restart_soc(struct device_d *dev)
>  {
>  	void __iomem *src_rstsr = (void *)(NOMADIK_SRC_BASE + 0x18);
>  
> @@ -28,6 +30,11 @@ void __noreturn reset_cpu(unsigned long addr)
>  	writel(1, src_rstsr);
>  
>  	/* Not reached */
> -	while (1);
> +	hang();
>  }
> -EXPORT_SYMBOL(reset_cpu);
> +
> +static int restart_register_feature(void)
> +{
> +	restart_register_handler(nomadik_restart_soc, NULL, FEATURE_SCOPE_SOC);
> +}
> +coredevice_initcall(restart_register_feature);
> diff --git a/arch/arm/mach-omap/am33xx_generic.c b/arch/arm/mach-omap/am33xx_generic.c
> index 8ac1290..2bdb569 100644
> --- a/arch/arm/mach-omap/am33xx_generic.c
> +++ b/arch/arm/mach-omap/am33xx_generic.c
> @@ -28,11 +28,11 @@
>  #include <mach/gpmc.h>
>  #include <restart.h>
>  
> -void __noreturn am33xx_reset_cpu(unsigned long addr)
> +void __noreturn am33xx_restart_soc(struct device_d *dev)
>  {
>  	writel(AM33XX_PRM_RSTCTRL_RESET, AM33XX_PRM_RSTCTRL);
>  
> -	while (1);
> +	hang();
>  }
>  
>  /**
> diff --git a/arch/arm/mach-omap/include/mach/am33xx-generic.h b/arch/arm/mach-omap/include/mach/am33xx-generic.h
> index 03418b0..22e2647 100644
> --- a/arch/arm/mach-omap/include/mach/am33xx-generic.h
> +++ b/arch/arm/mach-omap/include/mach/am33xx-generic.h
> @@ -28,7 +28,7 @@ u32 am33xx_running_in_flash(void);
>  u32 am33xx_running_in_sram(void);
>  u32 am33xx_running_in_sdram(void);
>  
> -void __noreturn am33xx_reset_cpu(unsigned long addr);
> +void __noreturn am33xx_restart_soc(struct device_d *dev);
>  
>  void am33xx_enable_per_clocks(void);
>  int am33xx_init(void);
> diff --git a/arch/arm/mach-omap/include/mach/omap3-generic.h b/arch/arm/mach-omap/include/mach/omap3-generic.h
> index 7db0838..945fe25 100644
> --- a/arch/arm/mach-omap/include/mach/omap3-generic.h
> +++ b/arch/arm/mach-omap/include/mach/omap3-generic.h
> @@ -24,7 +24,7 @@ u32 omap3_running_in_flash(void);
>  u32 omap3_running_in_sram(void);
>  u32 omap3_running_in_sdram(void);
>  
> -void __noreturn omap3_reset_cpu(unsigned long addr);
> +void __noreturn omap3_restart_soc(struct device_d *dev);
>  
>  int omap3_init(void);
>  int omap3_devices_init(void);
> diff --git a/arch/arm/mach-omap/include/mach/omap4-generic.h b/arch/arm/mach-omap/include/mach/omap4-generic.h
> index e246e36..dff3330 100644
> --- a/arch/arm/mach-omap/include/mach/omap4-generic.h
> +++ b/arch/arm/mach-omap/include/mach/omap4-generic.h
> @@ -18,7 +18,7 @@ static inline void omap4_save_bootinfo(uint32_t *info)
>  	memcpy((void *)OMAP44XX_SRAM_SCRATCH_SPACE, info, 3 * sizeof(uint32_t));
>  }
>  
> -void __noreturn omap4_reset_cpu(unsigned long addr);
> +void __noreturn omap4_restart_soc(struct device_d *dev);
>  
>  int omap4_init(void);
>  int omap4_devices_init(void);
> diff --git a/arch/arm/mach-omap/omap3_generic.c b/arch/arm/mach-omap/omap3_generic.c
> index dbb0b5f..88455ce 100644
> --- a/arch/arm/mach-omap/omap3_generic.c
> +++ b/arch/arm/mach-omap/omap3_generic.c
> @@ -52,13 +52,12 @@
>   *
>   * @return void
>   */
> -void __noreturn omap3_reset_cpu(unsigned long addr)
> +void __noreturn omap3_restart_soc(struct device_d *dev)
>  {
>  	writel(OMAP3_PRM_RSTCTRL_RESET, OMAP3_PRM_REG(RSTCTRL));
>  
> -	while (1);
> +	hang();
>  }
> -EXPORT_SYMBOL(reset_cpu);
>  
>  /**
>   * @brief Low level CPU type
> diff --git a/arch/arm/mach-omap/omap4_generic.c b/arch/arm/mach-omap/omap4_generic.c
> index 0b683da..2388d89 100644
> --- a/arch/arm/mach-omap/omap4_generic.c
> +++ b/arch/arm/mach-omap/omap4_generic.c
> @@ -34,11 +34,11 @@
>  #define EMIF_L3_CONFIG_VAL_SYS_10_LL_0		0x0A0000FF
>  #define EMIF_L3_CONFIG_VAL_SYS_10_MPU_3_LL_0	0x0A300000
>  
> -void __noreturn omap4_reset_cpu(unsigned long addr)
> +void __noreturn omap4_restart_soc(struct device_d *dev)
>  {
>  	writel(OMAP44XX_PRM_RSTCTRL_RESET, OMAP44XX_PRM_RSTCTRL);
>  
> -	while (1);
> +	hang;
>  }
>  
>  void omap4_set_warmboot_order(u32 *device_list)
> diff --git a/arch/arm/mach-omap/omap_generic.c b/arch/arm/mach-omap/omap_generic.c
> index 334cf8d..35f576f 100644
> --- a/arch/arm/mach-omap/omap_generic.c
> +++ b/arch/arm/mach-omap/omap_generic.c
> @@ -18,6 +18,7 @@
>  #include <boot.h>
>  #include <init.h>
>  #include <io.h>
> +#include <restart.h>
>  #include <fs.h>
>  #include <malloc.h>
>  #include <libfile.h>
> @@ -150,16 +151,17 @@ static int omap_env_init(void)
>  late_initcall(omap_env_init);
>  #endif
>  
> -void __noreturn reset_cpu(unsigned long addr)
> +static int restart_register_feature(void)
>  {
>  	if (cpu_is_omap3())
> -		omap3_reset_cpu(addr);
> +		restart_register_handler(omap3_restart_soc, NULL, FEATURE_SCOPE_SOC);
>  	if (cpu_is_omap4())
> -		omap4_reset_cpu(addr);
> +		restart_register_handler(omap4_restart_soc, NULL, FEATURE_SCOPE_SOC);
>  	if (cpu_is_am33xx())
> -		am33xx_reset_cpu(addr);
> -	while (1);
> +		restart_register_handler(am33xx_restart_soc, NULL, FEATURE_SCOPE_SOC);
> +	return 0;
>  }
> +coredevice_initcall(restart_register_feature);
>  
>  static int omap_soc_from_dt(void)
>  {
> diff --git a/arch/arm/mach-pxa/common.c b/arch/arm/mach-pxa/common.c
> index 2c27d81..3d6446d 100644
> --- a/arch/arm/mach-pxa/common.c
> +++ b/arch/arm/mach-pxa/common.c
> @@ -16,6 +16,8 @@
>   */
>  
>  #include <common.h>
> +#include <init.h>
> +#include <restart.h>
>  #include <mach/pxa-regs.h>
>  #include <asm/io.h>
>  
> @@ -29,7 +31,7 @@
>  
>  extern void pxa_clear_reset_source(void);
>  
> -void reset_cpu(ulong addr)
> +static void __noreturn pxa_restart_soc(struct device_d *dev)
>  {
>  	/* Clear last reset source */
>  	pxa_clear_reset_source();
> @@ -39,5 +41,11 @@ void reset_cpu(ulong addr)
>  	writel(OSSR_M3, OSSR);
>  	writel(readl(OSCR) + 368640, OSMR3);  /* ... in 100 ms */
>  
> -	while (1);
> +	hang();
>  }
> +
> +static int restart_register_feature(void)
> +{
> +	restart_register_handler(pxa_restart_soc, NULL, FEATURE_SCOPE_SOC);
> +}
> +coredevice_initcall(restart_register_feature);
> diff --git a/arch/arm/mach-rockchip/core.c b/arch/arm/mach-rockchip/core.c
> index bab06df..f59d3d2 100644
> --- a/arch/arm/mach-rockchip/core.c
> +++ b/arch/arm/mach-rockchip/core.c
> @@ -13,16 +13,22 @@
>  
>  #include <asm/io.h>
>  #include <common.h>
> +#include <init.h>
> +#include <restart.h>
>  #include <mach/rockchip-regs.h>
>  
> -void __noreturn reset_cpu(unsigned long addr)
> +static void __noreturn rockchip_restart_soc(struct device_d *dev)
>  {
>  	/* Map bootrom from address 0 */
>  	writel(RK_SOC_CON0_REMAP << 16, RK_GRF_BASE + RK_GRF_SOC_CON0);
>  	/* Reset */
>  	writel(0xeca8, RK_CRU_BASE + RK_CRU_GLB_SRST_SND);
>  
> -	while (1)
> -		;
> +	hang();
>  }
> -EXPORT_SYMBOL(reset_cpu);
> +
> +static int restart_register_feature(void)
> +{
> +	restart_register_handler(rockchip_restart_soc, NULL, FEATURE_SCOPE_SOC);
> +}
> +coredevice_initcall(restart_register_feature);
> diff --git a/arch/arm/mach-samsung/generic.c b/arch/arm/mach-samsung/generic.c
> index 75965d7..7f7bc36 100644
> --- a/arch/arm/mach-samsung/generic.c
> +++ b/arch/arm/mach-samsung/generic.c
> @@ -21,6 +21,7 @@
>  #include <config.h>
>  #include <common.h>
>  #include <init.h>
> +#include <restart.h>
>  #include <io.h>
>  #include <mach/s3c-iomap.h>
>  #include <mach/s3c-generic.h>
> @@ -29,7 +30,7 @@
>  #define S3C_WTDAT (S3C_WATCHDOG_BASE + 0x04)
>  #define S3C_WTCNT (S3C_WATCHDOG_BASE + 0x08)
>  
> -void __noreturn reset_cpu(unsigned long addr)
> +static void __noreturn samsung_restart_soc(struct device_d *dev)
>  {
>  	/* Disable watchdog */
>  	writew(0x0000, S3C_WTCON);
> @@ -41,7 +42,11 @@ void __noreturn reset_cpu(unsigned long addr)
>  	writew(0x0021, S3C_WTCON);
>  
>  	/* loop forever and wait for reset to happen */
> -	while(1)
> -		;
> +	hang();
>  }
> -EXPORT_SYMBOL(reset_cpu);
> +
> +static int restart_register_feature(void)
> +{
> +	restart_register_handler(samsung_restart_soc, NULL, FEATURE_SCOPE_SOC);
> +}
> +coredevice_initcall(restart_register_feature);
> diff --git a/arch/arm/mach-socfpga/reset-manager.c b/arch/arm/mach-socfpga/reset-manager.c
> index a9e7e14..eca1ee3 100644
> --- a/arch/arm/mach-socfpga/reset-manager.c
> +++ b/arch/arm/mach-socfpga/reset-manager.c
> @@ -17,6 +17,8 @@
>  
>  #include <common.h>
>  #include <io.h>
> +#include <init.h>
> +#include <restart.h>
>  #include <mach/socfpga-regs.h>
>  #include <mach/reset-manager.h>
>  
> @@ -38,7 +40,7 @@ void watchdog_disable(void)
>  }
>  
>  /* Write the reset manager register to cause reset */
> -void reset_cpu(ulong addr)
> +static void __noreturn socfpga_restart_soc(struct device_d *dev)
>  {
>  	/* request a warm reset */
>  	writel((1 << RSTMGR_CTRL_SWWARMRSTREQ_LSB),
> @@ -47,5 +49,11 @@ void reset_cpu(ulong addr)
>  	 * infinite loop here as watchdog will trigger and reset
>  	 * the processor
>  	 */
> -	while (1);
> +	hang();
>  }
> +
> +static int restart_register_feature(void)
> +{
> +	restart_register_handler(socfpga_restart_soc, NULL, FEATURE_SCOPE_SOC);
> +}
> +coredevice_initcall(restart_register_feature);
> diff --git a/arch/arm/mach-tegra/tegra20-pmc.c b/arch/arm/mach-tegra/tegra20-pmc.c
> index 6493eea..58dca08 100644
> --- a/arch/arm/mach-tegra/tegra20-pmc.c
> +++ b/arch/arm/mach-tegra/tegra20-pmc.c
> @@ -36,13 +36,12 @@ static void __iomem *pmc_base;
>  static int tegra_num_powerdomains;
>  
>  /* main SoC reset trigger */
> -void __noreturn reset_cpu(ulong addr)
> +static void __noreturn tegra20_restart_soc(struct device_d *dev)
>  {
>  	writel(PMC_CNTRL_MAIN_RST, pmc_base + PMC_CNTRL);
>  
> -	unreachable();
> +	hang();
>  }
> -EXPORT_SYMBOL(reset_cpu);
>  
>  static int tegra_powergate_set(int id, bool new_state)
>  {
> @@ -244,6 +243,7 @@ static struct driver_d tegra20_pmc_driver = {
>  
>  static int tegra20_pmc_init(void)
>  {
> +	restart_register_handler(tegra20_restart_soc, NULL, FEATURE_SCOPE_SOC);
>  	return platform_driver_register(&tegra20_pmc_driver);
>  }
>  coredevice_initcall(tegra20_pmc_init);
> diff --git a/arch/arm/mach-uemd/reset.c b/arch/arm/mach-uemd/reset.c
> deleted file mode 100644
> index 00ae0be..0000000
> --- a/arch/arm/mach-uemd/reset.c
> +++ /dev/null
> @@ -1,24 +0,0 @@
> -/*
> - * Copyright (C) 2014 Antony Pavlov <antonynpavlov@gmail.com>
> - *
> - * This file is part of barebox.
> - * See file CREDITS for list of people who contributed to this project.
> - *
> - * This program is free software; you can redistribute it and/or modify
> - * it under the terms of the GNU General Public License version 2
> - * as published by the Free Software Foundation.
> - *
> - * 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.
> - *
> - */
> -
> -#include <common.h>
> -
> -void __noreturn reset_cpu(ulong addr)
> -{
> -	hang();
> -}
> -EXPORT_SYMBOL(reset_cpu);
> diff --git a/arch/arm/mach-versatile/core.c b/arch/arm/mach-versatile/core.c
> index c671aa6..e2ceec6 100644
> --- a/arch/arm/mach-versatile/core.c
> +++ b/arch/arm/mach-versatile/core.c
> @@ -26,6 +26,7 @@
>  #include <init.h>
>  #include <clock.h>
>  #include <debug_ll.h>
> +#include <restart.h>
>  #include <linux/sizes.h>
>  
>  #include <linux/clkdev.h>
> @@ -184,7 +185,7 @@ void versatile_register_uart(unsigned id)
>  	amba_apb_device_add(NULL, "uart-pl011", id, start, 4096, NULL, 0);
>  }
>  
> -void __noreturn reset_cpu (unsigned long ignored)
> +static void versatile_reset_soc(struct device_d *dev)
>  {
>  	u32 val;
>  
> @@ -195,9 +196,8 @@ void __noreturn reset_cpu (unsigned long ignored)
>  	__raw_writel(val, VERSATILE_SYS_RESETCTL);
>  	__raw_writel(0, VERSATILE_SYS_LOCK);
>  
> -	while(1);
> +	hang();
>  }
> -EXPORT_SYMBOL(reset_cpu);
>  
>  static int versatile_init(void)
>  {
> @@ -205,6 +205,7 @@ static int versatile_init(void)
>  	amba_apb_device_add(NULL, "pl061_gpio", 1, 0x101e5000, 4096, NULL, 0);
>  	amba_apb_device_add(NULL, "pl061_gpio", 2, 0x101e6000, 4096, NULL, 0);
>  	amba_apb_device_add(NULL, "pl061_gpio", 3, 0x101e7000, 4096, NULL, 0);
> +	restart_register_handler(versatile_reset_soc, NULL, FEATURE_SCOPE_SOC);
>  	return 0;
>  }
>  coredevice_initcall(versatile_init);
> diff --git a/arch/arm/mach-vexpress/reset.c b/arch/arm/mach-vexpress/reset.c
> index ad6e06f..1cbc2b3 100644
> --- a/arch/arm/mach-vexpress/reset.c
> +++ b/arch/arm/mach-vexpress/reset.c
> @@ -6,17 +6,24 @@
>  
>  #include <common.h>
>  #include <io.h>
> +#include <init.h>
> +#include <restart.h>
>  #include <linux/amba/sp805.h>
>  
>  #include <mach/devices.h>
>  
>  void __iomem *v2m_wdt_base;
>  
> -void reset_cpu(ulong addr)
> +static void vexpress_reset_soc(struct device_d *dev)
>  {
>  	writel(LOAD_MIN, v2m_wdt_base + WDTLOAD);
>  	writeb(RESET_ENABLE, v2m_wdt_base + WDTCONTROL);
>  
> -	while (1)
> -		;
> +	hang();
>  }
> +
> +static int restart_register_feature(void)
> +{
> +	restart_register_handler(vexpress_reset_soc, NULL, FEATURE_SCOPE_SOC);
> +}
> +coredevice_initcall(restart_register_feature);
> diff --git a/arch/arm/mach-zynq/zynq.c b/arch/arm/mach-zynq/zynq.c
> index bd29e13..b541da1 100644
> --- a/arch/arm/mach-zynq/zynq.c
> +++ b/arch/arm/mach-zynq/zynq.c
> @@ -17,6 +17,7 @@
>  #include <asm-generic/io.h>
>  #include <common.h>
>  #include <init.h>
> +#include <restart.h>
>  #include <mach/zynq7000-regs.h>
>  
>  static int zynq_init(void)
> @@ -44,13 +45,18 @@ static int zynq_init(void)
>  }
>  postcore_initcall(zynq_init);
>  
> -void __noreturn reset_cpu(unsigned long addr)
> +static void __noreturn zynq_restart_soc(struct device_d *dev)
>  {
>  	/* write unlock key to slcr */
>  	writel(0xDF0D, ZYNQ_SLCR_UNLOCK);
>  	/* reset */
>  	writel(0x1, ZYNQ_PSS_RST_CTRL);
>  
> -	while (1)
> -		;
> +	hang();
>  }
> +
> +static int restart_register_feature(void)
> +{
> +	restart_register_handler(zynq_restart_soc, NULL, FEATURE_SCOPE_SOC);
> +}
> +coredevice_initcall(restart_register_feature);
> diff --git a/arch/blackfin/lib/cpu.c b/arch/blackfin/lib/cpu.c
> index 9d4c6e3..6c72e03 100644
> --- a/arch/blackfin/lib/cpu.c
> +++ b/arch/blackfin/lib/cpu.c
> @@ -27,8 +27,9 @@
>  #include <asm/entry.h>
>  #include <asm/cpu.h>
>  #include <init.h>
> +#include <restart.h>
>  
> -void __noreturn reset_cpu(unsigned long addr)
> +static void __noreturn blackfin_restart_cpu(struct device_d *dev)
>  {
>  	icache_disable();
>  
> @@ -41,9 +42,15 @@ void __noreturn reset_cpu(unsigned long addr)
>  	);
>  
>  	/* Not reached */
> -	while (1);
> +	hang();
>  }
>  
> +static int restart_register_feature(void)
> +{
> +	restart_register_handler(blackfin_restart_cpu, NULL, FEATURE_SCOPE_CPU);
> +}
> +coredevice_initcall(restart_register_feature);
> +
>  void icache_disable(void)
>  {
>  #ifdef __ADSPBF537__
> diff --git a/arch/efi/efi/efi.c b/arch/efi/efi/efi.c
> index d351775..9d8110b 100644
> --- a/arch/efi/efi/efi.c
> +++ b/arch/efi/efi/efi.c
> @@ -24,6 +24,7 @@
>  #include <command.h>
>  #include <magicvar.h>
>  #include <init.h>
> +#include <restart.h>
>  #include <driver.h>
>  #include <ns16550.h>
>  #include <io.h>
> @@ -246,13 +247,19 @@ static int efi_console_init(void)
>  }
>  console_initcall(efi_console_init);
>  
> -void reset_cpu(unsigned long addr)
> +static void __noreturn efi_restart_system(struct device_d *dev)
>  {
>  	RT->reset_system(EFI_RESET_WARM, EFI_SUCCESS, 0, NULL);
>  
> -	while(1);
> +	hang();
>  }
>  
> +static int restart_register_feature(void)
> +{
> +	restart_register_handler(efi_restart_cpu, NULL, FEATURE_SCOPE_MACHINE);
> +}
> +coredevice_initcall(restart_register_feature);
> +
>  extern char image_base[];
>  extern initcall_t __barebox_initcalls_start[], __barebox_early_initcalls_end[],
>  		  __barebox_initcalls_end[];
> diff --git a/arch/mips/mach-ar231x/ar231x_reset.c b/arch/mips/mach-ar231x/ar231x_reset.c
> index 0788add..3724bbe 100644
> --- a/arch/mips/mach-ar231x/ar231x_reset.c
> +++ b/arch/mips/mach-ar231x/ar231x_reset.c
> @@ -10,6 +10,7 @@
>  #include <common.h>
>  #include <init.h>
>  #include <io.h>
> +#include <restart.h>
>  #include <linux/err.h>
>  
>  #include <mach/ar2312_regs.h>
> @@ -17,16 +18,16 @@
>  
>  static void __iomem *reset_base;
>  
> -void __noreturn reset_cpu(ulong addr)
> +static void __noreturn ar2312x_restart_soc(struct device_d *dev)
>  {
>  	printf("reseting cpu\n");
>  	__raw_writel(0x10000,
>  		(char *)KSEG1ADDR(AR2312_WD_TIMER));
>  	__raw_writel(AR2312_WD_CTRL_RESET,
>  		(char *)KSEG1ADDR(AR2312_WD_CTRL));
> -	unreachable();
> +
> +	hang();
>  }
> -EXPORT_SYMBOL(reset_cpu);
>  
>  static u32 ar231x_reset_readl(void)
>  {
> @@ -69,6 +70,7 @@ static struct driver_d ar231x_reset_driver = {
>  
>  static int ar231x_reset_init(void)
>  {
> +	restart_register_handler(ar2312x_restart_soc, NULL, FEATURE_SCOPE_SOC);
>  	return platform_driver_register(&ar231x_reset_driver);
>  }
>  coredevice_initcall(ar231x_reset_init);
> diff --git a/arch/mips/mach-ath79/reset.c b/arch/mips/mach-ath79/reset.c
> index a0e9b34..757027f 100644
> --- a/arch/mips/mach-ath79/reset.c
> +++ b/arch/mips/mach-ath79/reset.c
> @@ -16,9 +16,11 @@
>   */
>  
>  #include <common.h>
> +#include <init.h>
> +#include <restart.h>
>  #include <mach/ath79.h>
>  
> -void __noreturn reset_cpu(ulong addr)
> +static void __noreturn ath79_restart_soc(struct device_d *dev)
>  {
>  	ath79_reset_wr(AR933X_RESET_REG_RESET_MODULE, AR71XX_RESET_FULL_CHIP);
>  	/*
> @@ -26,7 +28,12 @@ void __noreturn reset_cpu(ulong addr)
>  	 * pulling the reset pin. The system will reboot with PLL disabled.
>  	 * Always zero when read.
>  	 */
> -	unreachable();
> +	hang();
>  	/*NOTREACHED*/
>  }
> -EXPORT_SYMBOL(reset_cpu);
> +
> +static int restart_register_feature(void)
> +{
> +	restart_register_handler(ath79_restart_soc, NULL, FEATURE_SCOPE_SOC);
> +}
> +coredevice_initcall(restart_register_feature);
> diff --git a/arch/mips/mach-bcm47xx/reset.c b/arch/mips/mach-bcm47xx/reset.c
> index 00aee19..332047d 100644
> --- a/arch/mips/mach-bcm47xx/reset.c
> +++ b/arch/mips/mach-bcm47xx/reset.c
> @@ -17,12 +17,20 @@
>  
>  #include <common.h>
>  #include <io.h>
> +#include <init.h>
> +#include <restart.h>
>  #include <mach/hardware.h>
>  
> -void __noreturn reset_cpu(ulong addr)
> +static void __noreturn bcm47xx_restart_soc(struct device_d *dev)
>  {
>  	__raw_writel(GORESET, (char *)SOFTRES_REG);
> -	while (1);
> +
> +	hang();
>  	/*NOTREACHED*/
>  }
> -EXPORT_SYMBOL(reset_cpu);
> +
> +static int restart_register_feature(void)
> +{
> +	restart_register_handler(bcm47xx_restart_soc, NULL, FEATURE_SCOPE_SOC);
> +}
> +coredevice_initcall(restart_register_feature);
> diff --git a/arch/mips/mach-loongson/loongson1_reset.c b/arch/mips/mach-loongson/loongson1_reset.c
> index 8975392..fe02da6 100644
> --- a/arch/mips/mach-loongson/loongson1_reset.c
> +++ b/arch/mips/mach-loongson/loongson1_reset.c
> @@ -14,14 +14,21 @@
>  
>  #include <common.h>
>  #include <io.h>
> +#include <init.h>
> +#include <restart.h>
>  #include <mach/loongson1.h>
>  
> -void __noreturn reset_cpu(ulong addr)
> +static void __noreturn longhorn_restart_soc(struct device_d *dev)
>  {
>  	__raw_writel(0x1, LS1X_WDT_EN);
>  	__raw_writel(0x1, LS1X_WDT_SET);
>  	__raw_writel(0x1, LS1X_WDT_TIMER);
>  
> -	unreachable();
> +	hang();
>  }
> -EXPORT_SYMBOL(reset_cpu);
> +
> +static int restart_register_feature(void)
> +{
> +	restart_register_handler(longhorn_restart_soc, NULL, FEATURE_SCOPE_SOC);
> +}
> +coredevice_initcall(restart_register_feature);
> diff --git a/arch/mips/mach-malta/reset.c b/arch/mips/mach-malta/reset.c
> index f1dc68a..066535c 100644
> --- a/arch/mips/mach-malta/reset.c
> +++ b/arch/mips/mach-malta/reset.c
> @@ -22,12 +22,20 @@
>  
>  #include <common.h>
>  #include <io.h>
> +#include <init.h>
> +#include <restart.h>
>  #include <mach/hardware.h>
>  
> -void __noreturn reset_cpu(ulong addr)
> +static void __noreturn malta_restart_soc(struct device_d *dev)
>  {
>  	__raw_writel(GORESET, (char *)SOFTRES_REG);
> -	while (1);
> +
> +	hang();
>  	/*NOTREACHED*/
>  }
> -EXPORT_SYMBOL(reset_cpu);
> +
> +static int restart_register_feature(void)
> +{
> +	restart_register_handler(malta_restart_soc, NULL, FEATURE_SCOPE_SOC);
> +}
> +coredevice_initcall(restart_register_feature);
> diff --git a/arch/nios2/cpu/cpu.c b/arch/nios2/cpu/cpu.c
> index fdbe9f9..3ede3b8 100644
> --- a/arch/nios2/cpu/cpu.c
> +++ b/arch/nios2/cpu/cpu.c
> @@ -18,14 +18,22 @@
>   */
>  
>  #include <common.h>
> +#include <init.h>
> +#include <restart.h>
>  #include <asm/system.h>
>  
> -void __noreturn reset_cpu(ulong ignored)
> +static void __noreturn nios2_restart_soc(struct device_d *dev)
>  {
>  	/* indirect call to go beyond 256MB limitation of toolchain */
>  	nios2_callr(RESET_ADDR);
>  
>  	/* Not reached */
> -	while (1);
> +	hang();
>  }
>  
> +static int restart_register_feature(void)
> +{
> +	restart_register_handler(nios2_restart_soc, NULL, FEATURE_SCOPE_SOC);
> +}
> +coredevice_initcall(restart_register_feature);
> +
> diff --git a/arch/openrisc/cpu/cpu.c b/arch/openrisc/cpu/cpu.c
> index d73a418..6cedb26 100644
> --- a/arch/openrisc/cpu/cpu.c
> +++ b/arch/openrisc/cpu/cpu.c
> @@ -19,6 +19,7 @@
>  
>  #include <common.h>
>  #include <init.h>
> +#include <restart.h>
>  #include <asm/system.h>
>  #include <asm/openrisc_exc.h>
>  
> @@ -29,11 +30,17 @@ int cleanup_before_linux(void)
>  
>  extern void __reset(void);
>  
> -void __noreturn reset_cpu(ulong ignored)
> +static void __noreturn openrisc_restart_cpu(struct device_d *dev)
>  {
>  	__reset();
>  	/* not reached, __reset does not return */
>  
>  	/* Not reached */
> -	while (1);
> +	hang();
>  }
> +
> +static int restart_register_feature(void)
> +{
> +	restart_register_handler(openrisc_restart_cpu, NULL, FEATURE_SCOPE_CPU);
> +}
> +coredevice_initcall(restart_register_feature);
> diff --git a/arch/ppc/mach-mpc5xxx/cpu.c b/arch/ppc/mach-mpc5xxx/cpu.c
> index c860e70..c11a6cd 100644
> --- a/arch/ppc/mach-mpc5xxx/cpu.c
> +++ b/arch/ppc/mach-mpc5xxx/cpu.c
> @@ -31,6 +31,7 @@
>  #include <types.h>
>  #include <errno.h>
>  #include <of.h>
> +#include <restart.h>
>  #include <mach/clocks.h>
>  
>  int checkcpu (void)
> @@ -59,7 +60,7 @@ int checkcpu (void)
>  
>  /* ------------------------------------------------------------------------- */
>  
> -void __noreturn reset_cpu (unsigned long addr)
> +static void __noreturn mpc5xxx_restart_soc(struct device_d *dev)
>  {
>  	ulong msr;
>  	/* Interrupts and MMU off */
> @@ -71,9 +72,15 @@ void __noreturn reset_cpu (unsigned long addr)
>  	/* Charge the watchdog timer */
>  	*(vu_long *)(MPC5XXX_GPT0_COUNTER) = 0x0001000f;
>  	*(vu_long *)(MPC5XXX_GPT0_ENABLE) = 0x9004; /* wden|ce|timer_ms */
> -	while(1);
> +	hang();
>  }
>  
> +static int restart_register_feature(void)
> +{
> +	restart_register_handler(mpc5xxx_restart_soc, NULL, FEATURE_SCOPE_SOC);
> +}
> +coredevice_initcall(restart_register_feature);
> +
>  /* ------------------------------------------------------------------------- */
>  
>  #ifdef CONFIG_OFTREE
> diff --git a/arch/ppc/mach-mpc85xx/cpu.c b/arch/ppc/mach-mpc85xx/cpu.c
> index 7c183c1..a3fedae 100644
> --- a/arch/ppc/mach-mpc85xx/cpu.c
> +++ b/arch/ppc/mach-mpc85xx/cpu.c
> @@ -26,12 +26,13 @@
>  #include <common.h>
>  #include <memory.h>
>  #include <init.h>
> +#include <restart.h>
>  #include <asm/fsl_ddr_sdram.h>
>  #include <asm-generic/memory_layout.h>
>  #include <mach/mmu.h>
>  #include <mach/immap_85xx.h>
>  
> -void __noreturn reset_cpu(unsigned long addr)
> +static void __noreturn mpc85xx_restart_soc(struct device_d *dev)
>  {
>  	void __iomem *regs = (void __iomem *)MPC85xx_GUTS_ADDR;
>  
> @@ -39,10 +40,15 @@ void __noreturn reset_cpu(unsigned long addr)
>  	out_be32(regs + MPC85xx_GUTS_RSTCR_OFFSET, 0x2);  /* HRESET_REQ */
>  	udelay(100);
>  
> -	while (1)
> -		;
> +	hang();
>  }
>  
> +static int restart_register_feature(void)
> +{
> +	restart_register_handler(mpc85xx_restart_soc, NULL, FEATURE_SCOPE_SOC);
> +}
> +coredevice_initcall(restart_register_feature);
> +
>  long int initdram(int board_type)
>  {
>  	phys_size_t dram_size = 0;
> diff --git a/arch/sandbox/os/common.c b/arch/sandbox/os/common.c
> index d627391..61a816e 100644
> --- a/arch/sandbox/os/common.c
> +++ b/arch/sandbox/os/common.c
> @@ -28,6 +28,8 @@
>  #include <termios.h>
>  #include <unistd.h>
>  #include <fcntl.h>
> +#include <init.h>
> +#include <restart.h>
>  #include <time.h>
>  #include <getopt.h>
>  #include <sys/types.h>
> @@ -115,12 +117,18 @@ uint64_t linux_get_time(void)
>  	return now;
>  }
>  
> -void __attribute__((noreturn)) reset_cpu(unsigned long addr)
> +static void __attribute__((noreturn)) sandbox_restart_cpu(struct device_d *dev)
>  {
>  	cookmode();
>  	exit(0);
>  }
>  
> +static int restart_register_feature(void)
> +{
> +	restart_register_handler(sandbox_restart_cpu, NULL, FEATURE_SCOPE_CPU);
> +}
> +coredevice_initcall(restart_register_feature);
> +
>  int linux_read(int fd, void *buf, size_t count)
>  {
>  	ssize_t ret;
> diff --git a/arch/x86/mach-i386/reset.c b/arch/x86/mach-i386/reset.c
> deleted file mode 100644
> index 65f7d35..0000000
> --- a/arch/x86/mach-i386/reset.c
> +++ /dev/null
> @@ -1,30 +0,0 @@
> -/*
> - * Copyright (C) 2009 Juergen Beisert, Pengutronix
> - *
> - * 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.
> - *
> - *
> - */
> -
> -/**
> - * @file
> - * @brief Resetting an x86 CPU
> - */
> -
> -#include <common.h>
> -
> -void __noreturn reset_cpu(unsigned long addr)
> -{
> -	/** How to reset the machine? */
> -	while(1)
> -		;
> -}
> -EXPORT_SYMBOL(reset_cpu);
> diff --git a/commands/reset.c b/commands/reset.c
> index 4f42b91..8300480 100644
> --- a/commands/reset.c
> +++ b/commands/reset.c
> @@ -21,6 +21,7 @@
>  #include <command.h>
>  #include <complete.h>
>  #include <getopt.h>
> +#include <restart.h>
>  
>  static int cmd_reset(int argc, char *argv[])
>  {
> @@ -39,7 +40,7 @@ static int cmd_reset(int argc, char *argv[])
>  	if (shutdown_flag)
>  		shutdown_barebox();
>  
> -	reset_cpu(0);
> +	restart_machine();
>  
>  	/* Not reached */
>  	return 1;
> diff --git a/common/misc.c b/common/misc.c
> index 6da71c7..5532349 100644
> --- a/common/misc.c
> +++ b/common/misc.c
> @@ -24,6 +24,7 @@
>  #include <environment.h>
>  #include <led.h>
>  #include <of.h>
> +#include <restart.h>
>  
>  int errno;
>  EXPORT_SYMBOL(errno);
> @@ -206,7 +207,7 @@ void __noreturn panic(const char *fmt, ...)
>  		hang();
>  	} else {
>  		udelay(100000);	/* allow messages to go out */
> -		reset_cpu(0);
> +		restart_machine();
>  	}
>  }
>  EXPORT_SYMBOL(panic);
> diff --git a/common/restart.c b/common/restart.c
> index f73a9da..67797e4 100644
> --- a/common/restart.c
> +++ b/common/restart.c
> @@ -65,9 +65,64 @@ void reset_source_set(enum reset_src_type st, enum f_scope scope)
>  }
>  EXPORT_SYMBOL(reset_source_set);
>  
> +/* handle machine restart feature */
> +
> +static struct device_d *resetd;
> +static void (*resetf)(struct device_d*);
> +static int restart_scope;
> +
> +void __noreturn restart_machine(void)
> +{
> +	if (resetf != NULL)
> +		resetf(resetd);
> +	else
> +		pr_err("No restart handler available. Cannot restart system, hanging instead\n");

Can we save a few bytes here? "No restart handler registered" should be
enough, no?

> +	hang();
> +}
> +
> +static void restart_update_global_info(void)
> +{
> +	globalvar_add_simple("system.restart.unit",
> +				resetd == NULL ? "unknown" : resetd->name);
> +	globalvar_add_simple_enum("system.reset.scope", &restart_scope,
> +					scope_names, ARRAY_SIZE(scope_names));
> +}
> +
> +int restart_register_handler(void (*func)(struct device_d*), struct device_d *dev, enum f_scope scope)
> +{
> +	/* calling with a lower or equal scope will be ignored and is not a failure */
> +	if ((int)scope <= restart_scope)
> +		return 0;
> +
> +	resetf = func;
> +	resetd = dev;
> +	restart_scope = (int)scope;
> +	restart_update_global_info();

This call is unnecessary.

> +
> +	return 0;
> +}
> +EXPORT_SYMBOL(restart_register_handler);
> +
> +int restart_remove_handler(void (*func)(struct device_d*), struct device_d *dev)

void instead? I think no caller will be prepared for something else.

Sascha

-- 
Pengutronix e.K.                           |                             |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |
Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0    |
Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |

_______________________________________________
barebox mailing list
barebox@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/barebox

  reply	other threads:[~2015-06-24  6:42 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-06-23 12:57 [PATCHv2] Change barebox regarding "machine-restart", "reset cause detection" und "watchdog usage" Juergen Borleis
2015-06-23 12:58 ` [PATCH 1/5] Reset reason: add a scope value to the reset reason feature Juergen Borleis
2015-06-24  6:32   ` Sascha Hauer
2015-06-24  7:35     ` Juergen Borleis
2015-06-23 12:58 ` [PATCH 2/5] System restart: add a scope value to the system restart feature Juergen Borleis
2015-06-24  6:42   ` Sascha Hauer [this message]
2015-06-23 12:58 ` [PATCH 3/5] Watchdog: add a scope value to the watchdog feature Juergen Borleis
2015-06-24  6:51   ` Sascha Hauer
2015-06-23 12:58 ` [PATCH 4/5] Watchdog/i.MX: make the watchdog driver a regular driver Juergen Borleis
2015-06-23 12:58 ` [PATCH 5/5] MFD/DA9053: da9053: add basic da9053 driver Juergen Borleis
2015-06-25  7:34 [PATCHv3] Change barebox regarding "machine-restart", "reset cause detection" und "watchdog usage" Juergen Borleis
2015-06-25  7:34 ` [PATCH 2/5] System restart: add a scope value to the system restart feature Juergen Borleis

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20150624064208.GS6325@pengutronix.de \
    --to=s.hauer@pengutronix.de \
    --cc=barebox@lists.infradead.org \
    --cc=jbe@pengutronix.de \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox