linux-kernel - Re: [PATCH v3 4/5] ARM: tegra: set CPU reset handler with firmware op

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <CAAVeFuJMPZpz4jV4y12P=h-fJ2RSSCrzLWW5Uwges0WZH1Zb2w@mail.gmail.com>
Date:	Sun, 18 Aug 2013 17:37:08 +0900
From:	Alexandre Courbot <gnurou@...il.com>
To:	Stephen Warren <swarren@...dotorg.org>
Cc:	Alexandre Courbot <acourbot@...dia.com>,
	Russell King - ARM Linux <linux@....linux.org.uk>,
	Tomasz Figa <tomasz.figa@...il.com>,
	Dave Martin <Dave.Martin@....com>,
	Joseph Lo <josephl@...dia.com>,
	Jassi Brar <jassisinghbrar@...il.com>,
	"linux-arm-kernel@...ts.infradead.org" 
	<linux-arm-kernel@...ts.infradead.org>,
	"linux-tegra@...r.kernel.org" <linux-tegra@...r.kernel.org>,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH v3 4/5] ARM: tegra: set CPU reset handler with firmware op

On Thu, Aug 15, 2013 at 6:40 AM, Stephen Warren <swarren@...dotorg.org> wrote:
> On 08/12/2013 08:29 PM, Alexandre Courbot wrote:
>> Use a firmware operation to set the CPU reset handler and only resort to
>> doing it ourselves if there is none defined.
>>
>> This supports the booting of secondary CPUs on devices using a TrustZone
>> secure monitor.
>
>> diff --git a/arch/arm/mach-tegra/reset.c b/arch/arm/mach-tegra/reset.c
>
>> +     err = call_firmware_op(set_cpu_boot_addr, 0, reset_address);
>> +     switch (err) {
>> +     case -ENOSYS:
>> +             tegra_cpu_reset_handler_set(reset_address);
>> +             /* pass-through */
>> +     case 0:
>> +             is_enabled = true;
>> +             break;
>> +     default:
>> +             pr_crit("Cannot set CPU reset handler: %d\n", err);
>> +             BUG();
>> +     }
>
> Instead of trying and failing, does it make sense to register
> tegra_cpu_reset_handler_set() as the set_cpu_boot_addr firmware op when
> there is no firmware present? That would simplify all call-sites of any
> firmware op.

We discussed that point in v2 already IIRC (that is some time ago).
The reason I did it this way is because I wanted to follow the way
Tomasz was using his interface with Exynos - it seemed appropriate
that all users of an interface use it the same way. But if you prefer
to use a "non-firmware" firmware_ops for Tegra, I have absolutely
nothing against this.

Thanks,
Alex.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/