linux-kernel - Re: [PATCH 2.6.21-rt2] PowerPC: decrementer clockevent driver

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: <1179530872.32247.423.camel@localhost.localdomain>
Date:	Sat, 19 May 2007 09:27:52 +1000
From:	Benjamin Herrenschmidt <benh@...nel.crashing.org>
To:	Sergei Shtylyov <sshtylyov@...mvista.com>
Cc:	Dave Liu <r63238@...escale.com>, linuxppc-dev@...abs.org,
	tglx@...utronix.de, mingo@...e.hu, linux-kernel@...r.kernel.org
Subject: Re: [PATCH 2.6.21-rt2] PowerPC: decrementer clockevent driver

On Fri, 2007-05-18 at 17:41 +0400, Sergei Shtylyov wrote:
>     From the "PowerPC Operating Environment Architecture" that I've
> already 
> quoated t follows that POWER4-compatible decremented exception *must*
> be edge 
> triggered.
> 
> > says that an exception is generated when the MSB transitions from 0
> to
> > 1. It's not clear wether the exception sticks while that bit is 1 or
> is
> 
>     Freescale MPC 7450 manual says the same, for example. 

I find it extremely silly to implement it as edge anyway. The EE line is
level triggered, and having a mix of edge and level on the same
exception without a clean way to retrigger the DEC one other than
waiting one tick is just causing trouble.

Ben.


-
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/