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From: Segher Boessenkool <segher@kernel.crashing.org>
Subject: Re: Strange tg3 regression with UMP fw. link reporting
Date: Fri, 8 Aug 2008 10:58:58 +0200
To: benh@kernel.crashing.org
Cc: linuxppc-dev list <linuxppc-dev@ozlabs.org>, Nathan Lynch <ntl@pobox.com>,
	mcarlson@broadcom.com, Michael Chan <mchan@broadcom.com>,
	netdev <netdev@vger.kernel.org>
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> I don't know yet for sure what happens, but a quick look at the commit
> seems to show that the driver synchronously spin-waits for up to 2.5ms

That's what the comment says, but the code says 2.5 _seconds_:

+       /* Wait for up to 2.5 milliseconds */
+       for (i = 0; i < 250000; i++) {
+               if (!(tr32(GRC_RX_CPU_EVENT) & GRC_RX_CPU_DRIVER_EVENT))
+                       break;
+               udelay(10);
+       }

(not that milliseconds wouldn't be bad already...)


Segher