From: "wilbur.chan" <wilbur512@gmail.com>
To: Scott Wood <scottwood@freescale.com>
Cc: linuxppc-dev@ozlabs.org
Subject: Re: Can't write value into memory ?(E500 V2)
Date: Fri, 28 Aug 2009 00:27:15 +0800 [thread overview]
Message-ID: <e997b7420908270927m1ec1dbcbq51781e3b1e4db061@mail.gmail.com> (raw)
In-Reply-To: <4A96AD4B.1010204@freescale.com>
2009/8/27 Scott Wood <scottwood@freescale.com>:
>
> Is this under Linux (it is a Linux mailing list...)? =A0If so, there are
> better ways of communicating that don't involve clobbering random memory =
and
> overlapping userspace TLB mappings.
Yes, I'm doing this under linux in kernel mode.
I've used interrupt between cores, to make:
1) cpu0 carrys some data to a place (As a matter of fact ,the 'data'
is a kernel, the 'place' is at 0, and I'm using kexec..)
2) cpu0 writes a 'flag' to a physical address(16M), to indicate that ,
it has finished the carrying in step 1. And jump to new kernel directly.
3) cpu1 enters the loop by IRQ , checking the 'flag' from time to
time. If the 'flag' is true, it
breaks the loop and jumps to the instruction in new kernel.
> Do both cores have a mapping with the M bit (memory coherence required) s=
et?
What do you mean by M bit set?
I setup a 1:1 mapping in both cpu0 and cpu1, and invalidate all the
other entries in TLB1 and
TLB0
next prev parent reply other threads:[~2009-08-27 16:27 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-08-26 14:39 Can't write value into memory ?(E500 V2) wilbur.chan
2009-08-26 19:20 ` Scott Wood
2009-08-27 15:53 ` wilbur.chan
2009-08-27 15:59 ` Scott Wood
2009-08-27 16:27 ` wilbur.chan [this message]
2009-08-27 16:34 ` Scott Wood
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