(No Subject)

[David Woodhouse]

mkomiya at crossnet.co.jp said:
>  Our hardware has one flash memory in 16bit mode. CPU is SH4 of
> Hitachi. That is 32bit type CPU and can connect the device in 16bit
> mode. In this case, interleave is 1 and bus width is 2.

> Before using  cfi->device_type instead of CFI_DEVICETYPE_X8 MTD driver
> cannot calculate the address of the CFI command correctly.

Which CFI command is being sent to the wrong address? The unlock commands?

The cfi_cmdset_0002 code passes CFI_DEVICETYPE_X8 to the cfi_send_gen_cmd 
function when doing the unlock cycles, instead of cfi->device_type, because 
the unlock addresses (cfi->addr_unlock[12]) are supposed to have been 
pre-calculated so they don't need shifting.

I think that cfi_probe.c calculates the correct addresses for 8-bit chips 
and for 16-bit chips in 8-bit mode. I suspect that we may be calculating 
the wrong unlock addresses for 16-bit chips which are actually in 16-bit 
mode.

Your patch changes 8-bit devices to use (0xaaa,0x555) and changes _all_ 
16-bit devices to use (0x555,0x2aa). I suspect that you should be changing 
only the 16-bit devices _in 16-bit mode_ to use 0x555, 0x2aa, while leaving 
the 16-bit devices in 8-bit mode as they were.


--
dwmw2




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