From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lukasz Majewski Date: Tue, 23 Aug 2011 10:42:51 +0200 Subject: [U-Boot] [PATCH] mmc:dcache: Cache line size aligned internal MMC buffers In-Reply-To: <201108221208.43852.vapier@gentoo.org> References: <1313745913-28672-1-git-send-email-l.majewski@samsung.com> <201108191135.52532.vapier@gentoo.org> <20110822092952.66a8e2cb@lmajewski.digital.local> <201108221208.43852.vapier@gentoo.org> Message-ID: <20110823104251.18293e20@lmajewski.digital.local> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Hi Mike, On Mon, 22 Aug 2011 12:08:42 -0400 Mike Frysinger wrote: > On Monday, August 22, 2011 03:29:52 Lukasz Majewski wrote: > > On Fri, 19 Aug 2011 11:35:50 -0400 Mike Frysinger wrote: > > > On Friday, August 19, 2011 11:28:18 Lukasz Majewski wrote: > > > > On Fri, 19 Aug 2011 09:57:10 -0400 Mike Frysinger wrote: > > > > > On Friday, August 19, 2011 05:25:13 Lukasz Majewski wrote: > > > > > also, what is the code size increase with your patch ? > > > > > > > > Code size overhead (s5p_goni target): > > > > Without proposed changes: 167928 B (u-boot.bin) > > > > With changes: 168208 B (u-boot.bin) > > > > > > > > Delta: 280 B > > > > > > np if it gives significant (more than system noise) speedups. any > > > details on that ? > > > > No tests performed yet. The goal of those patches is to preserve the > > MMC subsystem functionality when dcache is enabled (the ext_csd[512] > > corruption is observed with d-cache enabled). > > so you're papering over a bug in some controller's cache handling ? > shouldnt you fix the controller in question by having it flush its > caches ? aligning random buffers to make cache issues "go away" isnt > the right way for anything. -mike Please look into the following patch: http://patchwork.ozlabs.org/patch/110576/ It seems that only flushing/invalidating buffers is not enough. -- Best regards, Lukasz Majewski Samsung Poland R&D Center Platform Group