From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754379AbbKYQiT (ORCPT ); Wed, 25 Nov 2015 11:38:19 -0500 Received: from mout.kundenserver.de ([217.72.192.75]:52278 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753362AbbKYQdB (ORCPT ); Wed, 25 Nov 2015 11:33:01 -0500 From: Arnd Bergmann To: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org, Linus Walleij , Russell King , Liviu Dudau , Sudeep Holla , Lorenzo Pieralisi , Arnd Bergmann , Russell King Subject: [PATCH 04/10] ARM: no longer force unbuffered DMA for realview Date: Wed, 25 Nov 2015 17:32:17 +0100 Message-Id: <1448469143-447355-5-git-send-email-arnd@arndb.de> X-Mailer: git-send-email 2.1.0.rc2 In-Reply-To: <1448469143-447355-1-git-send-email-arnd@arndb.de> References: <1448469143-447355-1-git-send-email-arnd@arndb.de> X-Provags-ID: V03:K0:qAWnXauyl+ObdwAQ4o4Pb7BEIkosBwVckaGl1i/VSVJ+YWLZBvO mOwh5XZ//bxIAvH0mOWb7+axLw45ZVy7/tLR9JUh1iAH+cdff67yuGK0cbPbBzUR7naDo4f kj7BI5Cr3yG2dnxPyC1/MepFTlzVx1zfEXbZBNy22TUWfJ3fg8/qPTVCuXv3gPm4Chtw5QU NNI6mIc71ZXSgn5ksx1dw== X-UI-Out-Filterresults: notjunk:1;V01:K0:QDM4DifZsfY=:3PrdAQYBzeuJUKun4Up4Fx BoHZilSgSg9AvfpCV7mcrMPrRNhPZCWHbDy6ynngw/AzNlk4CsGj5WqJhmLXPjycp8zVJgBPt yqgjOBvYb9H99BJ4gmk5hzqyCvqV6K5KR7HIiHzCjDHmXu2F+ybOk3sy+9O+1FbVBorjlHIvd YvkdN7fCL0JfqOFvTkE5aAqxqzB8E3dv+nEH6xIpMgtgJBh6T6MP8we/2RUxcbS/Z/OWTEDbS Vz1zgdDrVNcQo2HgaoAhxkQ5luH4bRXvF4cOYmlT4WOnSHc17vBdREy88OZp3bwUjTs7vWehr 2ds5i35xQWGkxsOP9rTluZ5VgazU1MpQTkmRADO+WK3cweBpqabR3P3el7hqguh/QhUvq1Cd6 TooKyJMiNfrGjWdaybtCc5m5yUyZI6AE6t0BC0TyyUQQEd5D3hA3pi2E10hf8oi3eIj9sePhp zf/SLZLZUu4i3TDi45muAiEGOuuinxhB3mItp7nEINFSjsc+BhfPE3MsPZaQeP0AP7Oa8z2ii L3dW5fX2OOcv7Lo24KsSKB/KfnZfRCMOYjq+rbKU+c3R//aHEUDbpMSpkf7G+khLL8hCPvTwz YkshY+PE80pCraw62EhO+9AH7Sp0W5mBsyySSuDfXunnaEyWGTLCe0zq8iK4p2I2M4b9PBgyE 0Mm9mPeIeiOVFxrVoaWJ1pkyBGnTcHSr9HRZfZl4tMjhGFYna19CCP2fMe/kvDM9fxSM= Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit 42c4dafe803dca ("ARM: 6202/1: Do not ARM_DMA_MEM_BUFFERABLE on RealView boards with L210/L220") changed the generic setting for ARM_DMA_MEM_BUFFERABLE to be disabled on any Realview kernel that includes support for any of the ARM11 variations. Doing this was required to allow doing DMA without a lockup in the l2x0 cache controller on the Realview platform. Unfortunately, in a kernel that also contains support for any ARMv7 based machine, the same change makes it impossible to do DMA on ARMv7, which gets in the way of enabling multiplatform support on Realview. As confirmed by Catalin Marinas and Linus Walleij, the current code for Realview that we have in the kernel does not actually perform any DMA, and this is unlikely to change in the future. Therefore we can revert 42c4dafe803dca without introducing regressions, but we must never start using DMA on this platform in the future. Signed-off-by: Arnd Bergmann Acked-by: Linus Walleij Cc: Russell King --- arch/arm/mm/Kconfig | 2 -- 1 file changed, 2 deletions(-) diff --git a/arch/arm/mm/Kconfig b/arch/arm/mm/Kconfig index 41218867a9a6..76f65f2d59b1 100644 --- a/arch/arm/mm/Kconfig +++ b/arch/arm/mm/Kconfig @@ -1005,8 +1005,6 @@ config ARM_L1_CACHE_SHIFT config ARM_DMA_MEM_BUFFERABLE bool "Use non-cacheable memory for DMA" if (CPU_V6 || CPU_V6K) && !CPU_V7 - depends on !(MACH_REALVIEW_PB1176 || REALVIEW_EB_ARM11MP || \ - MACH_REALVIEW_PB11MP) default y if CPU_V6 || CPU_V6K || CPU_V7 help Historically, the kernel has used strongly ordered mappings to -- 2.1.0.rc2