[flashrom] [coreboot] Tester devices [was: QA contribution]
juhe at iki.fi
Thu Feb 17 21:13:59 CET 2011
Carl-Daniel Hailfinger wrote:
> If you tell me about the design constraints of your device, I can
> probably come up with a flashrom driver which can reflash an 1 MByte ROM
> in ~5 minutes or so. That will require some cooperation from your
> device, but should be doable with ~270 bytes of RAM. Even with ~140
> bytes of RAM we should be able to get some decent performance. As long
> as we can optimize the protocol, it should be possible to get acceptable
> performance even with only 50 bytes of RAM, but generally more RAM will
> give you better performance.
The tester device is basically an Atmel AT90USB162, which has USB and
SPI ports. Data sheet and a detailed manual are available on Atmel web
pages. The USB is connected to the Linux host. SPI and some I/O pins are
used to control a multiplexer and an SPI flash chip.
The microcontroller can be programmed in C with gcc, and I am using the
open-source LUFA library for USB drivers on the device side.
The microcontroller has 16 Kbytes Flash ROM, 512 bytes SRAM, and a
separate 176 byte buffer RAM in the USB controller. The CPU runs at 16
MHz. I have so far used the SPI bus at 1 MHz.
The USB controller supports up to 5 endpoints, including default control
endpoint. Maximum packet size is 64 bytes. Two of the endpoints can be
double buffered in hardware.
Is this enough details, or do you need something else?
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