Re: [PATCH v2] net: phy: add Maxlinear GPY115/21x/24x driver

On 3/6/2021 11:21 pm, Andrew Lunn wrote:

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On Thu, Jun 03, 2021 at 03:10:31PM +0000, Liang Xu wrote:

quoted

On 3/6/2021 5:17 pm, Russell King (Oracle) wrote:

quoted

quoted

+static int gpy_config_init(struct phy_device *phydev)
+{
+ int ret, fw_ver;
+
+ /* Show GPY PHY FW version in dmesg */
+ fw_ver = phy_read(phydev, PHY_FWV);
+ if (fw_ver < 0)
+ return fw_ver;
+
+ phydev_info(phydev, "Firmware Version: 0x%04X (%s)\n", fw_ver,
+ (fw_ver & PHY_FWV_REL_MASK) ? "release" : "test");

Does this need to print the firmware version each time config_init()
is called? Is it likely to change beyond? Would it be more sensible
to print it in the probe() method?

The firmware version can change in device with different firmware
loading mechanism.

I moved the print to probe and tested a few devices, found in some cases
it did not print the active version number.

That actually sounds like a real problem. If it is still in the
bootloader when the driver is probed, the driver should not be writing
any configuration registers until the real image is running. So it
sounds like you need a probe function which checks if the PHY has
finished booting, and if not, wait for the real firmware to start
running.

         Andrew

I think my word was misleading.

The device always has valid firmware running.

The firmware version can change because of switch of the firmware during 
running time.