From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8A745C31E49 for ; Wed, 19 Jun 2019 10:51:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 682B82080C for ; Wed, 19 Jun 2019 10:51:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727248AbfFSKvK (ORCPT ); Wed, 19 Jun 2019 06:51:10 -0400 Received: from verein.lst.de ([213.95.11.211]:52653 "EHLO newverein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726751AbfFSKvJ (ORCPT ); Wed, 19 Jun 2019 06:51:09 -0400 Received: by newverein.lst.de (Postfix, from userid 2407) id BE4D768AA6; Wed, 19 Jun 2019 12:50:39 +0200 (CEST) Date: Wed, 19 Jun 2019 12:50:39 +0200 From: Christoph Hellwig To: benh@kernel.crashing.org, paulus@samba.org, mpe@ellerman.id.au Cc: Larry.Finger@lwfinger.net, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, aaro.koskinen@iki.fi Subject: Re: [PATCH] powerpc: enable a 30-bit ZONE_DMA for 32-bit pmac Message-ID: <20190619105039.GA10118@lst.de> References: <20190613082446.18685-1-hch@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190613082446.18685-1-hch@lst.de> User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Any chance this could get picked up to fix the regression? On Thu, Jun 13, 2019 at 10:24:46AM +0200, Christoph Hellwig wrote: > With the strict dma mask checking introduced with the switch to > the generic DMA direct code common wifi chips on 32-bit powerbooks > stopped working. Add a 30-bit ZONE_DMA to the 32-bit pmac builds > to allow them to reliably allocate dma coherent memory. > > Fixes: 65a21b71f948 ("powerpc/dma: remove dma_nommu_dma_supported") > Reported-by: Aaro Koskinen > Signed-off-by: Christoph Hellwig > --- > arch/powerpc/include/asm/page.h | 7 +++++++ > arch/powerpc/mm/mem.c | 3 ++- > arch/powerpc/platforms/powermac/Kconfig | 1 + > 3 files changed, 10 insertions(+), 1 deletion(-) > > diff --git a/arch/powerpc/include/asm/page.h b/arch/powerpc/include/asm/page.h > index b8286a2013b4..0d52f57fca04 100644 > --- a/arch/powerpc/include/asm/page.h > +++ b/arch/powerpc/include/asm/page.h > @@ -319,6 +319,13 @@ struct vm_area_struct; > #endif /* __ASSEMBLY__ */ > #include > > +/* > + * Allow 30-bit DMA for very limited Broadcom wifi chips on many powerbooks. > + */ > +#ifdef CONFIG_PPC32 > +#define ARCH_ZONE_DMA_BITS 30 > +#else > #define ARCH_ZONE_DMA_BITS 31 > +#endif > > #endif /* _ASM_POWERPC_PAGE_H */ > diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c > index cba29131bccc..2540d3b2588c 100644 > --- a/arch/powerpc/mm/mem.c > +++ b/arch/powerpc/mm/mem.c > @@ -248,7 +248,8 @@ void __init paging_init(void) > (long int)((top_of_ram - total_ram) >> 20)); > > #ifdef CONFIG_ZONE_DMA > - max_zone_pfns[ZONE_DMA] = min(max_low_pfn, 0x7fffffffUL >> PAGE_SHIFT); > + max_zone_pfns[ZONE_DMA] = min(max_low_pfn, > + ((1UL << ARCH_ZONE_DMA_BITS) - 1) >> PAGE_SHIFT); > #endif > max_zone_pfns[ZONE_NORMAL] = max_low_pfn; > #ifdef CONFIG_HIGHMEM > diff --git a/arch/powerpc/platforms/powermac/Kconfig b/arch/powerpc/platforms/powermac/Kconfig > index f834a19ed772..c02d8c503b29 100644 > --- a/arch/powerpc/platforms/powermac/Kconfig > +++ b/arch/powerpc/platforms/powermac/Kconfig > @@ -7,6 +7,7 @@ config PPC_PMAC > select PPC_INDIRECT_PCI if PPC32 > select PPC_MPC106 if PPC32 > select PPC_NATIVE > + select ZONE_DMA if PPC32 > default y > > config PPC_PMAC64 > -- > 2.20.1 ---end quoted text---