Subject: Re: [PATCH 2/3] net: qcom/emac: do not reset the EMAC during initialization

From: Timur Tabi <[email-masked]>
Date: Fri, 23 Jun 2017 13:37:58 -0500

On 06/23/2017 01:00 PM, David Miller wrote:
> What if the boot loader or something else left the chip in
> a weird state?

We depend on the boot loader leaving the NIC in a very specific state 
already, otherwise the driver can't initialize the hardware.  The 
firmware has to pre-initialize the EMAC for us.

Not only that, but the driver was resetting the MAC *after* programming 
the clocks (on non-ACPI systems) and initializing both PHYs.

> I'm not applying this.
> 
> If it's correct, the explanation in this commit message need
> to be imporved.  The change must be better justified.

Since this is for ACPI systems, I could do this:

	if (!has_acpi_companion(&pdev->dev))
		emac_mac_reset(adpt);

But at the very least, the call should be moved to earlier in the function.

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