Some of the other things which I am experiencing which may help to trace this issue.
1: For Core 0 printk is not working in setup_arch "just before call to paging_init", where as on Core 1 printk is working in the same function. I see the source uses ppc_md.progress to display debug messages so it seems printk will not work then why it is working on Core 1. 2: During kernel boot of both cores boot messages of Core 0 are mixed in Core 1 messages. 3: If I change memory partitioning to following, then on Core 1 when I mmap shared memory area (starting 0x0C00,0000) I receive error that can not mmap RAM. If my both systems memory partitions are defined clearly then this area does not belong to system RAM then I shouldn't receive this error in this memory partitioning. Core Base Address Size Core 0 0x0000,0000 0x0C00,0000 --> CONFIG_PHYSICAL_START = bootm_low = Base Address Shared Mem 0x0C00,0000 0x0400,0000 Core 1 0x1000,0000 0x1000,0000 --> CONFIG_PHYSICAL_START = bootm_low = Base Address I believe there is some bug / or patch which I am missing in both kernels memory initialization which is causing all these issues. Kernel sources / configuration of both cores are 100% same except (CONFIG_PHYSICAL_START) param and kernel version is 2.6.32.13. Any thoughts. Regards, Farrukh Arshad -----Original Message----- From: Arshad, Farrukh Sent: Wednesday, January 04, 2012 11:50 AM To: 'Scott Wood' Cc: linuxppc-dev@lists.ozlabs.org Subject: RE: Problem in getting shared memory access on P1022RDK 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 Regards, Farrukh Arshad -----Original Message----- From: Scott Wood [mailto:scottw...@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 _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
