[coreboot] SB600 SPI Driver for Flashrom (unfinished)

[Peter Stuge]

Sean Nelson wrote:
> sb600 spi driver file for flashrom

This one needs some more work.

The SB600 SPI controller registers aren't IO mapped like on the
superios, but memory mapped according to the 0xa0 BAR in the LPC
bridge. See page 260 of 46155_sb600_rrg_pub_3.03.pdf.

This driver must also be careful to properly synchronize when ROM
sharing is being used.


Some more comments:


> +static uint16_t find_sb600_spi_flash_port(uint16_t device_id)
> +{
> +	struct pci_dev *dev;
> +	uint16_t flashport = 0;
> +
> +	/* sb600's LPC ISA Bridge */
> +	dev = pci_dev_find(0x1002, device_id);

Must check return value here:

	if (!dev)
		return 1;


> +int sb600_probe_spi_flash(const char *name)
> +{
> +	sb600_flashport = find_ite_spi_flash_port(0x438d);
> +
> +	if (sb600_flashport)
> +		flashbus = BUS_TYPE_SB600_SPI;
> +
> +	return (!it8716f_flashport);
> +}

I'd prefer merging these two functions into one because
find_ite_spi_flash_port() will never be called from anywhere else.

Also there seems to be a copypaste error here, it8716f_flashport
can't be right. :)


> +int sb600_spi_command(unsigned int writecnt, unsigned int readcnt, const unsigned char *writearr, unsigned char *readarr)
> +{
> +	uint8_t busy, speed;
> +	int i;
> +
> +	if (readcnt > 8) {
> +		printf("%s called with unsupported readcnt %i.\n",
> +			__FUNCTION__, readcnt);
> +		return 1;
> +	}

Make sure to check writecnt as well. And please use __func__ instead
of __FUNCTION__ everywhere.


//Peter