FPGA device memory is not accessible with ioremap()

[Sri Ram Vemulpali]

Thanks for reply Haresh. Will try and let u know.

Thanks,
Sri


On Thu, Dec 26, 2013 at 5:09 PM, haresh langaraman <hareshel at gmail.com>wrote:

> Hi ram,
>
> Can you try to map the address using io_table_init table of kernel
> initialization code.
>
> Thanks,
> Haresh.
> On 27 Dec 2013 05:12, "Sri Ram Vemulpali" <sri.ram.gmu06 at gmail.com> wrote:
>
>> Hi All,
>>
>> I am using custom board MPC8641d. It has all evaluation board devices
>> connected. Apart from that an external FPGA device connected through
>> localbus.
>>
>> The localbus is at address 0xF5005000 directly connected to processor.
>> The FPGA address in the processor realm is 0xF3800000. As per spec FPGA
>> target interface is CS3 (chip select 3). 32-bit peripheral address bus as
>> seen by FPGA is 0xF3800000. The global address of FPGA is 0x0BFC0000.
>>
>>
>> I am implementing driver for FPGA. I am using ioremap() to map to FPGA
>> registers at location 0xF3800000. The virtual address returned by ioremap()
>> when used with write32(), read32() at memory locations shows no response
>> from device. FPGA has special scratch pad to which one can write and read
>> to validate the memory map is working. When I write and read I see no value.
>>
>> #define FCP_ADDRESS_START 0xF3800000
>> #define FCP_ADDRESS_END   0xF3808000
>> #define FCP_ADDRESS_RANGE (FCP_ADDRESS_END - FCP_ADDRESS_START)
>>
>>  void *fcp_scratch_pad;
>>  char buff[10];
>>
>>  io_fcp_mem = ioremap_nocache( FCP_ADDRESS_START, FCP_ADDRESS_RANGE );
>>
>>         if( ! io_fcp_mem ) {
>>                 return -ENODEV;
>>         }
>>
>>         printk( KERN_CRIT "ioremap virt mem:%p\n", io_fcp_mem );
>>
>>         fcp_scratch_pad = ((char*)io_fcp_mem) + 224;
>>
>>         printk( KERN_CRIT "scratch pad virt mem:%p\n", fcp_scratch_pad );
>>
>>         iowrite8_rep( fcp_scratch_pad, "Hello", 6 );
>>
>>         ioread8_rep( fcp_scratch_pad, buff, 6 );
>>
>>         printk( KERN_CRIT "value read from scratch_pad:%s\n", buff );
>>
>>         return 0;
>>
>>
>> Attached is the device tree of the board.
>>
>> Can anyone please direct me or point where I am doing wrong. It seems I
>> am unable to access FPGA device memory. Thanks.
>>
>> --
>> Regards,
>> Sri.
>>
>> _______________________________________________
>> Kernelnewbies mailing list
>> Kernelnewbies at kernelnewbies.org
>> http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
>>
>>


-- 
Regards,
Sri.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.kernelnewbies.org/pipermail/kernelnewbies/attachments/20131226/2344f93f/attachment.html