Re: [Qemu-devel] Testing sysbus devices

[Stephen Checkoway]

On Feb 19, 2019, at 01:09, Markus Armbruster <address@hidden> wrote:

> Stephen Checkoway <address@hidden> writes:
> 
>> On Feb 18, 2019, at 13:08, Markus Armbruster <address@hidden> wrote:
>> 
>>> Any chance you could do multiple region support, too?
>> 
>> Can you point me at the data sheet for a flash chip with multiple region 
>> support? For my purposes, I only need the features I mentioned, but if it's 
>> a simple change, I'll consider it.
> 
> I'm not familiar with CFI pflash, but I can operate a search engine.
> Have a look at page 27 and 56 of
> 
> https://media.digikey.com/pdf/Data%20Sheets/Intel%20PDFs/28F160C3,320C3,640C3,800C3%20(x16).pdf
> 
> and tell us whether it's helpful.

That's a flash chip that uses the Intel command set (pflash_cfi01.c in qemu), 
I'm only touching the AMD command set (pflash_cfi02.c). Also those pages seem 
to be about block locking, not multiple regions.

I'm not entirely sure what you meant by multiple regions. If you meant blocks* 
having different sizes (usually in the top or bottom of the flash as boot 
blocks), then I've implemented that (the nonuniform sectors* I mentioned in my 
first email).

* Some flash chips differentiate between sectors and blocks. E.g., the flash 
chip used by hw/arm/musicpal.c 
<http://ww1.microchip.com/downloads/en/DeviceDoc/SST39VF6401B-SST39VF6402B-64-Mbit-x16-Multi-Purpose-Flash-Plus-Data-Sheet-DS20005008C.pdf>
 has sectors and blocks with separate erase commands. Qemu treats these the 
same and does not support separate erase commands.

> I think a test would be quite welcome even if it only tests what's
> testable now with reasonable effort.

I used Thomas Huth's suggestion for testing the autoselect, CFI, sector erase, 
chip erase, programming, and reset commands. I'll see how much I can test.

-- 
Stephen Checkoway