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Message-ID: <dfe6451c93574b61d4bdde4a05c5f8ccf86b31a0.camel@kernel.crashing.org>
Subject: Re: [BISECTED REGRESSION] b43legacy broken on G4 PowerBook
From:   Benjamin Herrenschmidt <benh@kernel.crashing.org>
To:     Aaro Koskinen <aaro.koskinen@iki.fi>,
        Christoph Hellwig <hch@lst.de>,
        Christian Zigotzky <chzigotzky@xenosoft.de>,
        Michael Ellerman <mpe@ellerman.id.au>,
        Larry Finger <Larry.Finger@lwfinger.net>
Cc:     linuxppc-dev@lists.ozlabs.org, linux-wireless@vger.kernel.org,
        linux-kernel@vger.kernel.org
Date:   Thu, 06 Jun 2019 10:54:51 +1000
In-Reply-To: <20190605225059.GA9953@darkstar.musicnaut.iki.fi>
References: <20190605225059.GA9953@darkstar.musicnaut.iki.fi>
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On Thu, 2019-06-06 at 01:50 +0300, Aaro Koskinen wrote:
> Hi,
> 
> When upgrading from v5.0 -> v5.1 on G4 PowerBook, I noticed WLAN does
> not work anymore:
> 
> [   42.004303] b43legacy-phy0: Loading firmware version 0x127, patch level 14 (2005-04-18 02:36:27)
> [   42.184837] b43legacy-phy0 debug: Chip initialized
> [   42.184873] b43legacy-phy0 ERROR: The machine/kernel does not support the required 30-bit DMA mask
> 
> The same happens with the current mainline.

How much RAM do you have ?

Ben.

> 
> Bisected to:
> 
> 	commit 65a21b71f948406201e4f62e41f06513350ca390
> 	Author: Christoph Hellwig <hch@lst.de>
> 	Date:   Wed Feb 13 08:01:26 2019 +0100
> 
> 	    powerpc/dma: remove dma_nommu_dma_supported
> 
> 	    This function is largely identical to the generic version used
> 	    everywhere else.  Replace it with the generic version.
> 
> 	    Signed-off-by: Christoph Hellwig <hch@lst.de>
> 	    Tested-by: Christian Zigotzky <chzigotzky@xenosoft.de>
> 	    Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
> 
> A.