From mboxrd@z Thu Jan 1 00:00:00 1970 From: Krzysztof Kozlowski Subject: Re: [PATCH v2] ARM: exynos_defconfig: increase CONFIG_CMA_SIZE_MBYTES to 96 Date: Wed, 1 Mar 2017 19:09:10 +0200 Message-ID: <20170301170910.4vvn4eeolkjbgzw5@kozik-lap> References: <20170228191221.18135-1-shuahkh@osg.samsung.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Return-path: Content-Disposition: inline In-Reply-To: <20170228191221.18135-1-shuahkh@osg.samsung.com> Sender: linux-kernel-owner@vger.kernel.org To: Shuah Khan Cc: linux@armlinux.org.uk, kgene@kernel.org, javier@osg.samsung.com, arnd@arndb.de, cw00.choi@samsung.com, rafael.j.wysocki@intel.com, robie@justgohome.co.uk, b.zolnierkie@samsung.com, viresh.kumar@linaro.org, m.szyprowski@samsung.com, s.nawrocki@samsung.com, a.hajda@samsung.com, inki.dae@samsung.com, sw0312.kim@samsung.com, shuah@kernel.org, linux-arm-kernel@lists.infradead.org, linux-samsung-soc@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: linux-samsung-soc@vger.kernel.org On Tue, Feb 28, 2017 at 12:12:21PM -0700, Shuah Khan wrote: > Current CMA size of 64 Mbytes is right on the edge of being small when > several drivers need to allocate large CMA buffers. > > For example, if the s5p-mfc driver needs to pre-allocate N MiB CMA memory Everything looks good but I don't get this "N MiB". What do you mean by that? If N is infinite (or not known) then how do you know that 96 MiB will be enough? Best regards, Krzysztof > to decode a H.264 1080p video, then there won't be enough CMA memory left > for other drivers, such as the exynos-drm driver that may need to allocate > GEM buffers for the display manager. > > Increasing CMA size to 96 Mbytes in exynos_defconfig addresses use-cases > such as these. > > Suggested-by: Marek Szyprowski > Signed-off-by: Shuah Khan > Reviewed-by: Javier Martinez Canillas > --- > > Changes since v1: > Fix short and long commit log. > > Reason for this patch: > With the proposed s5p_mfc patch series that pre-allocate buffers, when > display manager starts, it fails to get GEM buffers. Increasing the CMA > size to 96 solved the problem. > > arch/arm/configs/exynos_defconfig | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/arm/configs/exynos_defconfig b/arch/arm/configs/exynos_defconfig > index 742baf0..2541414 100644 > --- a/arch/arm/configs/exynos_defconfig > +++ b/arch/arm/configs/exynos_defconfig > @@ -53,7 +53,7 @@ CONFIG_RFKILL_REGULATOR=y > CONFIG_DEVTMPFS=y > CONFIG_DEVTMPFS_MOUNT=y > CONFIG_DMA_CMA=y > -CONFIG_CMA_SIZE_MBYTES=64 > +CONFIG_CMA_SIZE_MBYTES=96 > CONFIG_BLK_DEV_LOOP=y > CONFIG_BLK_DEV_CRYPTOLOOP=y > CONFIG_BLK_DEV_RAM=y > -- > 2.7.4 >