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From: "tiejun.chen" <tiejun.chen@windriver•com>
To: "Arshad, Farrukh" <Farrukh_Arshad@mentor•com>
Cc: Scott Wood <scottwood@freescale•com>,
	"linuxppc-dev@lists•ozlabs.org" <linuxppc-dev@lists•ozlabs.org>
Subject: Re: Problem in getting shared memory access on P1022RDK
Date: Thu, 5 Jan 2012 10:09:23 +0800	[thread overview]
Message-ID: <4F050653.6010601@windriver.com> (raw)
In-Reply-To: <93CD5F41FDBC6042A6B449764F3B35CC050CCB2E@EU-MBX-03.mgc.mentorg.com>

Arshad, Farrukh wrote:
> How can I verify if the memory mapped is coherent on both cores. My memory partitioning is given below
> 
> Core		Base Address		Size
> Core 0		0x0000,0000		0x1000,0000	--> CONFIG_PHYSICAL_START = bootm_low = Base Address
> Core 1		0x1000,0000		0x0C00,0000	--> CONFIG_PHYSICAL_START = bootm_low = Base Address
> Shared Mem	0x1C00,0000		0x0400,0000

Was the kernel option, CONFIG_SMP, enabled for both two kernels?

CONFIG_SMP would affect the memory attribute for cache coherency. Maybe you
should make sure if kernel have a appropriate memory attribute by dumping TLB entry.

Tiejun

> 
> Regards,
> Farrukh Arshad
> 
> -----Original Message-----
> From: Scott Wood [mailto:scottwood@freescale•com] 
> Sent: Tuesday, January 03, 2012 10:10 PM
> To: Arshad, Farrukh
> Cc: linuxppc-dev@lists•ozlabs.org
> Subject: Re: Problem in getting shared memory access on P1022RDK
> 
> On 01/03/2012 03:42 AM, Arshad, Farrukh wrote:
>> Adding more to it,
>>
>>  
>>
>> When I write from Core 1 on the shared memory region it is visible at 
>> Core 0 and it can read what I have written from Core 1 but when I 
>> write from Core 0 on this shared memory it is not visible on Core 1.
> 
> Is the memory mapped coherent on both cores?
> 
> -Scott

  reply	other threads:[~2012-01-05  2:09 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-01-02 19:10 Problem in getting shared memory access on P1022RDK Arshad, Farrukh
2012-01-03  9:42 ` Arshad, Farrukh
2012-01-03 17:10   ` Scott Wood
2012-01-04  6:49     ` Arshad, Farrukh
2012-01-05  2:09       ` tiejun.chen [this message]
2012-01-05  5:46         ` Arshad, Farrukh
2012-01-11 15:52         ` Arshad, Farrukh
2012-01-12  8:09           ` tiejun.chen
2012-01-25 11:04             ` Arshad, Farrukh
2012-01-29  3:15               ` tiejun.chen
2012-01-04  9:56     ` Arshad, Farrukh

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