Re: [net-next RFC PATCH v6 3/4] net: phy: aquantia: add firmware load support

[Christophe JAILLET <christophe.jaillet@wanadoo.fr>]

Le 09/11/2023 à 13:32, Christian Marangi a écrit :
> From: Robert Marko <robimarko@gmail.com>
> 
> Aquantia PHY-s require firmware to be loaded before they start operating.
> It can be automatically loaded in case when there is a SPI-NOR connected
> to Aquantia PHY-s or can be loaded from the host via MDIO.
> 
> This patch adds support for loading the firmware via MDIO as in most cases
> there is no SPI-NOR being used to save on cost.
> Firmware loading code itself is ported from mainline U-boot with cleanups.
> 
> The firmware has mixed values both in big and little endian.
> PHY core itself is big-endian but it expects values to be in little-endian.
> The firmware is little-endian but CRC-16 value for it is stored at the end
> of firmware in big-endian.
> 
> It seems the PHY does the conversion internally from firmware that is
> little-endian to the PHY that is big-endian on using the mailbox
> but mailbox returns a big-endian CRC-16 to verify the written data
> integrity.
> 
> Co-developed-by: Christian Marangi <ansuelsmth@gmail.com>
> Signed-off-by: Robert Marko <robimarko@gmail.com>
> Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
> ---

...

> +static int aqr_firmware_load_fs(struct phy_device *phydev)
> +{
> +	struct device *dev = &phydev->mdio.dev;
> +	const struct firmware *fw;
> +	const char *fw_name;
> +	int ret;
> +
> +	ret = of_property_read_string(dev->of_node, "firmware-name",
> +				      &fw_name);
> +	if (ret)
> +		return ret;
> +
> +	ret = request_firmware(&fw, fw_name, dev);
> +	if (ret) {
> +		phydev_err(phydev, "failed to find FW file %s (%d)\n",
> +			   fw_name, ret);
> +		goto exit;

Harmless, but a direct return looks correct as-well.
No need to call release_firmware() here.

> +	}
> +
> +	ret = aqr_fw_boot(phydev, fw->data, fw->size, AQR_FW_SRC_FS);
> +	if (ret)
> +		phydev_err(phydev, "firmware loading failed: %d\n", ret);
> +
> +exit:
> +	release_firmware(fw);
> +
> +	return ret;
> +}

...