From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from bhuna.collabora.co.uk ([46.235.227.227]:38046 "EHLO bhuna.collabora.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727233AbeH3VYO (ORCPT ); Thu, 30 Aug 2018 17:24:14 -0400 From: Ezequiel Garcia To: linux-media@vger.kernel.org, linux-usb@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Cc: Laurent Pinchart , Tomasz Figa , "Matwey V . Kornilov" , Alan Stern , kernel@collabora.com, Keiichi Watanabe , Ezequiel Garcia Subject: [RFC 1/3] HACK: ARM: dma-mapping: Get writeback memory for non-consistent mappings Date: Thu, 30 Aug 2018 14:20:28 -0300 Message-Id: <20180830172030.23344-2-ezequiel@collabora.com> In-Reply-To: <20180830172030.23344-1-ezequiel@collabora.com> References: <20180830172030.23344-1-ezequiel@collabora.com> Sender: linux-media-owner@vger.kernel.org List-ID: This is obviously a hack. Signed-off-by: Ezequiel Garcia --- arch/arm/include/asm/pgtable.h | 3 +++ arch/arm/mm/dma-mapping.c | 9 ++++++--- 2 files changed, 9 insertions(+), 3 deletions(-) diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h index a757401129f9..37ddd0d73434 100644 --- a/arch/arm/include/asm/pgtable.h +++ b/arch/arm/include/asm/pgtable.h @@ -122,6 +122,9 @@ extern pgprot_t pgprot_s2_device; #define pgprot_writecombine(prot) \ __pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_BUFFERABLE) +#define pgprot_writeback(prot) \ + __pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_WRITEBACK) + #define pgprot_stronglyordered(prot) \ __pgprot_modify(prot, L_PTE_MT_MASK, L_PTE_MT_UNCACHED) diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index 66566472c153..11cca7bbb0a8 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -633,9 +633,12 @@ static void __free_from_contiguous(struct device *dev, struct page *page, static inline pgprot_t __get_dma_pgprot(unsigned long attrs, pgprot_t prot) { - prot = (attrs & DMA_ATTR_WRITE_COMBINE) ? - pgprot_writecombine(prot) : - pgprot_dmacoherent(prot); + if (attrs & DMA_ATTR_WRITE_COMBINE) + prot = pgprot_writecombine(prot); + else if (attrs & DMA_ATTR_NON_CONSISTENT) + prot = pgprot_writeback(prot); + else + prot = pgprot_dmacoherent(prot); return prot; } -- 2.18.0