IB/hfi1: Add ability to read platform config from the EPROM

done_asic:

	return ret;

}

/* magic character sequence that trails an image */

#define IMAGE_TRAIL_MAGIC "egamiAPO"

/*

 * Read all of partition 1.  The actual file is at the front.  Adjust

 * the returned size if a trailing image magic is found.

 */

static int read_partition_platform_config(struct hfi1_devdata *dd, void **data,

					  u32 *size)

{

	void *buffer;

	void *p;

	u32 length;

	int ret;

	buffer = kmalloc(P1_SIZE, GFP_KERNEL);

	if (!buffer)

		return -ENOMEM;

	ret = read_length(dd, P1_START, P1_SIZE, buffer);

	if (ret) {

		kfree(buffer);

		return ret;

	}

	/* scan for image magic that may trail the actual data */

	p = strnstr(buffer, IMAGE_TRAIL_MAGIC, P1_SIZE);

	if (p)

		length = p - buffer;

	else

		length = P1_SIZE;

	*data = buffer;

	*size = length;

	return 0;

}

/*

 * Read the platform configuration file from the EPROM.

 *

 * On success, an allocated buffer containing the data and its size are

 * returned.  It is up to the caller to free this buffer.

 *

 * Return value:

 *   0	      - success

 *   -ENXIO   - no EPROM is available

 *   -EBUSY   - not able to acquire access to the EPROM

 *   -ENOENT  - no recognizable file written

 *   -ENOMEM  - buffer could not be allocated

 */

int eprom_read_platform_config(struct hfi1_devdata *dd, void **data, u32 *size)

{

	u32 directory[EP_PAGE_DWORDS]; /* aligned buffer */

	int ret;

	if (!dd->eprom_available)

		return -ENXIO;

	ret = acquire_chip_resource(dd, CR_EPROM, EPROM_TIMEOUT);

	if (ret)

		return -EBUSY;

	/* read the last page of P0 for the EPROM format magic */

	ret = read_length(dd, P1_START - EP_PAGE_SIZE, EP_PAGE_SIZE, directory);

	if (ret)

		goto done;

	/* last dword of P0 contains a magic indicator */

	if (directory[EP_PAGE_DWORDS - 1] == 0) {

		/* partition format */

		ret = read_partition_platform_config(dd, data, size);

		goto done;

	}

	/* nothing recognized */

	ret = -ENOENT;

done:

	release_chip_resource(dd, CR_EPROM);

	return ret;

}

struct hfi1_devdata;

int eprom_init(struct hfi1_devdata *dd);

int eprom_read_platform_config(struct hfi1_devdata *dd, void **buf_ret,

			       u32 *size_ret);