From mboxrd@z Thu Jan 1 00:00:00 1970 From: pawel.moll@arm.com (Pawel Moll) Date: Mon, 24 Jan 2011 17:54:18 -0000 Subject: [PATCH] arm: Improve MMC performance on Versatile Express In-Reply-To: <20110124170304.GH24104@n2100.arm.linux.org.uk> References: <1295618352-26432-1-git-send-email-pawel.moll@arm.com> <000001cbbbc2$0e815e80$2b841b80$@moll@arm.com> <20110124133513.GL16202@n2100.arm.linux.org.uk> <20110124162400.GC24104@n2100.arm.linux.org.uk> <000101cbbbe5$45d47ed0$d17d7c70$@moll@arm.com> <20110124165356.GG24104@n2100.arm.linux.org.uk> <20110124170304.GH24104@n2100.arm.linux.org.uk> Message-ID: <000201cbbbef$bcec4610$36c4d230$@moll@arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org > My final mail on this subject. Ah, and I was really enjoying our pleasant discussion... > Take a mainline kernel. Apply the attached three patches. MMC > will then work without any problems. No hacks required. There is > *absolutely* *no* need to waste time with hardware modifications. > > With this you will find that MMCI FIFO underruns/overruns are no > longer any problem. $ git log -1 commit d315777b32a4696feb86f2a0c9e9f39c94683649 Merge: 5a05a6d 1765e3a Author: Linus Torvalds Date: Mon Jan 24 19:58:39 2011 +1000 [...] $ git diff > changes.diff Attached, I trust you will find all your changes there (and only them). / # uname -a Linux (none) 2.6.38-rc2+ #11 SMP Mon Jan 24 17:11:35 GMT 2011 armv7l GNU/Linux / # cat /dev/sda > /dev/null & / # dd if=/dev/mmcblk0 of=/dev/null bs=64k count=128 dd: /dev/mmcblk0: Input/output error And dmesg is full of: [...] mmcblk0: error -5 transferring data, sector 254, nr 2, cmd response 0x900, card status 0xb00 end_request: I/O error, dev mmcblk0, sector 254 mmcblk0: error -5 transferring data, sector 255, nr 1, cmd response 0x900, card status 0xb00 end_request: I/O error, dev mmcblk0, sector 255 mmcblk0: error -5 transferring data, sector 0, nr 8, cmd response 0x900, card status 0x900 mmcblk0: retrying using single block read mmcblk0: error -5 transferring data, sector 0, nr 8, cmd response 0x900, card status 0xb00 [...] Now: $ git am 0001-arm-Improve-MMC-performance-on-Versatile-Express.patch / # uname -a Linux (none) 2.6.38-rc2+ #12 SMP Mon Jan 24 17:41:53 GMT 2011 armv7l GNU/Linux / # cat /dev/sda > /dev/null & / # dd if=/dev/mmcblk0 of=/dev/null bs=64k count=128 128+0 records in 128+0 records out 8388608 bytes (8.0MB) copied, 1.501529 seconds, 5.3MB/s > THERE IS NO ISSUE WITH MMCI. THE HARDWARE DOES NOT NEED "FIXING". I'm really pleased you think so. It's always nice to have happy customers :-) Cheers! Pawe? -------------- next part -------------- A non-text attachment was scrubbed... Name: changes.diff Type: application/octet-stream Size: 7990 bytes Desc: not available URL: