From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from static-ip-62-75-166-246.inaddr.intergenia.de ([62.75.166.246]:60561 "EHLO vs166246.vserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752855AbXKZPNN convert rfc822-to-8bit (ORCPT ); Mon, 26 Nov 2007 10:13:13 -0500 From: Michael Buesch To: Larry Finger Subject: Re: [PATCH V3] b43: Changes to enable BCM4311 rev 02 with wireless core revision 13 Date: Mon, 26 Nov 2007 16:11:52 +0100 Cc: John Linville , Broadcom Linux , wireless References: <474ADA53.808@lwfinger.net> In-Reply-To: <474ADA53.808@lwfinger.net> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Message-Id: <200711261611.52975.mb@bu3sch.de> (sfid-20071126_151315_332134_8F0FA333) Sender: linux-wireless-owner@vger.kernel.org List-ID: On Monday 26 November 2007 15:38:11 Larry Finger wrote: > The BCM94311MCG rev 02 chip has an 802.11 core with revision 13 and > has not been supported until now. The changes include the following: >=20 > (1) Add the 802.11 rev 13 device to the ssb_device_id table to load b= 43. > (2) Add PHY revision 9 to the supported list. > (3) Change the 2-bit routing code for address extensions to 0b10 rath= er > than the 0b01 used for the 32-bit case. > (4) Remove some magic numbers in the DMA setup. >=20 > The DMA implementation for this chip supports full 64-bit addressing = with > one exception. Whenever the Descriptor Ring Buffer is in high memory,= a > fatal DMA error occurs. This problem was not present in 2.6.24-rc2 du= e > to code to "Bias the placement of kernel pages at lower PFNs". When > commit 44048d70 reverted that code, the DMA error appeared. As a "fix= ", > use the GFP_DMA flag when allocating the buffer for 64-bit DMA. At pr= esent, > this problem is thought to arise from a hardware error. >=20 > This patch has been tested on my system, and by C=C3=A9dric Caumont > and by Matthieu PATOU on a BCM4= 312. >=20 > Signed-off-by: Larry Finger > static int alloc_ringmemory(struct b43_dmaring *ring) > { > struct device *dev =3D ring->dev->dev->dev; > + gfp_t flags =3D GFP_KERNEL; >=20 > + /* The specs call for 4K buffers for 30- and 32-bit DMA with 4K > + * alignment and 8K buffers for 64-bit DMA with 8K alignment. Testi= ng > + * has shown that 4K is sufficient for the latter as long as the bu= ffer > + * does not cross an 8K boundary. > + * > + * For unknown reasons - possibly a hardware error - the BCM4311 re= v > + * 02, which uses 64-bit DMA, needs the ring buffer in very low mem= ory, > + * which accounts for the GFP_DMA flag below. > + */ > + if (ring->dma64) > + flags =3D GFP_DMA; Whoops, didn't notice this before. This needs to be flags |=3D GFP_DMA; > ring->descbase =3D dma_alloc_coherent(dev, B43_DMA_RINGMEMSIZE, > - &(ring->dmabase), GFP_KERNEL); > + &(ring->dmabase), flags); > if (!ring->descbase) { > b43err(ring->dev->wl, "DMA ringmemory allocation failed\n"); > return -ENOMEM; The rest is acked. --=20 Greetings Michael. - To unsubscribe from this list: send the line "unsubscribe linux-wireles= s" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html