From: Mark Rutland <mark.rutland@arm.com>
To: Guenter Roeck <linux@roeck-us.net>
Cc: Russell King <linux@arm.linux.org.uk>,
Catalin Marinas <catalin.marinas@arm.com>,
Wolfram Sang <wsa@the-dreams.de>,
Geert Uytterhoeven <geert@linux-m68k.org>,
linux-arm-kernel@lists.infradead.org,
linux-kernel@vger.kernel.org,
Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Subject: Re: [PATCH 3/6] ARM: PSCI: Register with kernel restart handler
Date: Wed, 13 Apr 2016 12:05:19 +0100 [thread overview]
Message-ID: <20160413110519.GE32018@leverpostej> (raw)
In-Reply-To: <1460120039-2497-4-git-send-email-linux@roeck-us.net>
On Fri, Apr 08, 2016 at 05:53:56AM -0700, Guenter Roeck wrote:
> Register with kernel restart handler instead of setting arm_pm_restart
> directly. This enables support for replacing the PSCI restart handler
> with a different handler if necessary for a specific board.
>
> Select a priority of 129 to indicate a higher than default priority, but
> keep it as low as possible since PSCI reset is known to fail on some
> boards.
For reference, which boards?
It's unfortunate that that a PSCI 0.2+ implementation would be lacking a
working SYSTEM_RESET implementation, and it's certainly a mistake to
discourage.
> Signed-off-by: Guenter Roeck <linux@roeck-us.net>
> ---
> It might make sense to introduce a restart-priority property for devicetree
> based configurations, but I am not sure if this would be acceptable.
>From the DT side, I'm not keen on properties for priorities. They're
incredibly fragile and don't really encode a HW property.
A better option would be to have a property to describe how the PSCI
implementation is broken (e.g. broken-system-reset), and not register
the handler at all in that case.
Thanks,
Mark.
> drivers/firmware/psci.c | 11 +++++++++--
> 1 file changed, 9 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/firmware/psci.c b/drivers/firmware/psci.c
> index 11bfee8b79a9..99fab3ac3fd5 100644
> --- a/drivers/firmware/psci.c
> +++ b/drivers/firmware/psci.c
> @@ -231,11 +231,18 @@ static int get_set_conduit_method(struct device_node *np)
> return 0;
> }
>
> -static void psci_sys_reset(enum reboot_mode reboot_mode, const char *cmd)
> +static int psci_sys_reset(struct notifier_block *np, unsigned long action,
> + void *data)
> {
> invoke_psci_fn(PSCI_0_2_FN_SYSTEM_RESET, 0, 0, 0);
> + return NOTIFY_DONE;
> }
>
> +static struct notifier_block psci_sys_reset_nb = {
> + .notifier_call = psci_sys_reset,
> + .priority = 129,
> +};
> +
> static void psci_sys_poweroff(void)
> {
> invoke_psci_fn(PSCI_0_2_FN_SYSTEM_OFF, 0, 0, 0);
> @@ -461,7 +468,7 @@ static void __init psci_0_2_set_functions(void)
>
> psci_ops.migrate_info_type = psci_migrate_info_type;
>
> - arm_pm_restart = psci_sys_reset;
> + register_restart_handler(&psci_sys_reset_nb);
>
> pm_power_off = psci_sys_poweroff;
> }
> --
> 2.5.0
>
next prev parent reply other threads:[~2016-04-13 11:05 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-04-08 12:53 [PATCH 0/6] ARM/ARM64: Drop arm_pm_restart Guenter Roeck
2016-04-08 12:53 ` [PATCH 1/6] ARM: prima2: Register with kernel restart handler Guenter Roeck
2016-04-08 12:53 ` [PATCH 2/6] ARM: xen: " Guenter Roeck
[not found] ` <20160408152257.GJ15411@char.us.oracle.com>
2016-04-08 18:20 ` [Xen-devel] " Guenter Roeck
2016-04-09 23:46 ` Stefano Stabellini
2016-04-09 23:56 ` Stefano Stabellini
2016-04-08 12:53 ` [PATCH 3/6] ARM: PSCI: " Guenter Roeck
2016-04-12 15:36 ` Wolfram Sang
2016-04-13 11:05 ` Mark Rutland [this message]
2016-04-13 11:24 ` Jisheng Zhang
2016-04-13 13:10 ` Guenter Roeck
2016-04-13 13:22 ` Geert Uytterhoeven
2016-04-14 0:42 ` Guenter Roeck
2016-04-14 8:52 ` Wolfram Sang
2016-04-14 13:21 ` Guenter Roeck
2016-04-14 14:31 ` Wolfram Sang
2016-04-08 12:53 ` [PATCH 4/6] ARM: " Guenter Roeck
2016-04-08 12:53 ` [PATCH 5/6] ARM64: Remove arm_pm_restart Guenter Roeck
2016-04-12 13:10 ` Catalin Marinas
2016-04-08 12:53 ` [PATCH 6/6] ARM: " Guenter Roeck
2016-04-08 15:44 ` [PATCH 0/6] ARM/ARM64: Drop arm_pm_restart Wolfram Sang
2016-04-08 20:46 ` Arnd Bergmann
2016-04-12 15:41 ` Wolfram Sang
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=20160413110519.GE32018@leverpostej \
--to=mark.rutland@arm.com \
--cc=catalin.marinas@arm.com \
--cc=geert@linux-m68k.org \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux@arm.linux.org.uk \
--cc=linux@roeck-us.net \
--cc=lorenzo.pieralisi@arm.com \
--cc=wsa@the-dreams.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;
as well as URLs for NNTP newsgroup(s).