From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vladimir Murzin Subject: Re: [PATCH v2 0/4] Enable DMA on STM32 MCU based on cortex-M7 Date: Wed, 28 Feb 2018 13:22:51 +0000 Message-ID: References: <1519823458-27734-1-git-send-email-alexandre.torgue@st.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1519823458-27734-1-git-send-email-alexandre.torgue@st.com> Content-Language: en-GB List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: Alexandre Torgue , Maxime Coquelin , arnd@arndb.de, robh+dt@kernel.org, mark.rutland@arm.com, linux@armlinux.org.uk, patrice.chotard@st.com, lee.jones@linaro.org Cc: devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org List-Id: devicetree@vger.kernel.org On 28/02/18 13:10, Alexandre Torgue wrote: > This series enable DMA on several STM32 MCU based on cortex-M7. > To make it possible, a dedicated dma pool memory area has to be > created. This patchset activate also ARM_MPU flag which will configure > MPU (Memory Protection Unit) according to devicetree information (mem > and dma-pool). Note that on cortex-M7 DMA has to use a NO cache-able > memory region. > > > v2: > -select ARM_MPU in mach-stm32 Kconfig instead of add it in stm32 defconfig > -Remove XIP configuration from stm32_defconfig: ARM_MPU flag imposes XIP image > to be aligned on 1MB. It is currently not the case. I had choice to either > modify current XIP start address to be aligned on 1MB or to remove global > configuration. I make choice to remove XIP configuration. Indeed, SD card > support has been recently added for most of STM32 MCU boards (except for > stm32f429-disco). As kernel is growing up for stm32 it will be more and more > difficult to flash it in embeded flash (max size: 2MB). It is sad we are loosing XIP configuration - it used to uncover some bugs in a past. Probably, you might consider to have stm32 tiny (+xip) defconfig for those who do not want/need all-in-one kernel. Cheers Vladimir > -fix typo in commit message > > Regards > Alex > > Alexandre Torgue (4): > ARM: dts: stm32: add DMA memory pool on MCU which embed a cortex-M7 > ARM: configs: stm32: remove XIP configuration > ARM: stm32: Select ARM_MPU for cortex-M7 machines > ARM: dts: stm32: enable dma on MCU which embed a cortex-M7 > > arch/arm/boot/dts/stm32746g-eval.dts | 21 +++++++++++++++++++++ > arch/arm/boot/dts/stm32f769-disco.dts | 21 +++++++++++++++++++++ > arch/arm/boot/dts/stm32h743i-disco.dts | 21 +++++++++++++++++++++ > arch/arm/boot/dts/stm32h743i-eval.dts | 21 +++++++++++++++++++++ > arch/arm/configs/stm32_defconfig | 2 -- > arch/arm/mach-stm32/Kconfig | 3 +++ > 6 files changed, 87 insertions(+), 2 deletions(-) >