Re: [RFC net-next 1/4] net: marvell: prestera: try to load previous fw version

On Thu, May 20, 2021 at 03:12:02AM +0200, Andrew Lunn wrote:

quoted

+static int prestera_fw_get(struct prestera_fw *fw)
+{
+	int ver_maj = PRESTERA_SUPP_FW_MAJ_VER;
+	int ver_min = PRESTERA_SUPP_FW_MIN_VER;
+	char fw_path[128];
+	int err;
+
+pick_fw_ver:
+	snprintf(fw_path, sizeof(fw_path), PRESTERA_FW_PATH_FMT,
+		 ver_maj, ver_min);
+
+	err = request_firmware_direct(&fw->bin, fw_path, fw->dev.dev);
+	if (err) {
+		if (ver_maj == PRESTERA_SUPP_FW_MAJ_VER) {
+			ver_maj--;
+			goto pick_fw_ver;
+		} else {
+			dev_err(fw->dev.dev, "failed to request firmware file\n");
+			return err;
+		}
+	}

So lets say for the sake of the argument, you have version 3.0 and
2.42. It looks like this code will first try to load version 3.0. If
that fails, ver_maj is decremented, so it tries 2.0, which also fails
because it should be looking for 2.42. I don't think this decrement is
a good idea.

Ahh, you are correct, I was too focused on a major version. So the only
option which I see is to hard-code also the previous version.

Also:

quoted

+			dev_err(fw->dev.dev, "failed to request firmware file\n");

It would be useful to say what version you are actually looking for,
so the user can go find the correct firmware.

I agree.

   Andrew

Thanks,