From mboxrd@z Thu Jan 1 00:00:00 1970 From: Heiko Schocher Date: Tue, 17 Sep 2013 06:32:37 +0200 Subject: [U-Boot] [PATCH v4 2/3] dfu: ram support In-Reply-To: <52c881e52b562c139fb8e289491d7fc2ebad2033.1379090444.git.afzal.mohd.ma@gmail.com> References: <52c881e52b562c139fb8e289491d7fc2ebad2033.1379090444.git.afzal.mohd.ma@gmail.com> Message-ID: <5237DB65.5010801@denx.de> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Hello Afzal, Am 13.09.2013 19:00, schrieb Afzal Mohammed: > DFU spec mentions it as a method to upgrade firmware (software stored > in writable non-volatile memory). It also says other potential uses of > DFU is beyond scope of the spec. > > Here such a beyond the scope use is being attempted - directly pumping > binary images from host via USB to RAM. This facility is a developer > centric one in that it gives advantage over upgrading non-volatile > memory for testing new images every time during development and/or > testing. > > Directly putting image onto RAM would speed up upgrade process. This and > convenience was the initial thoughts that led to doing this, speed > improvement over MMC was only 1 second though - 6 sec on RAM as opposed > to 7 sec on MMC in beagle bone, perhaps enabling cache and/or optimizing > DFU framework to avoid multiple copy for ram (if worth) may help, and > on other platforms and other boot media like NAND maybe improvement > would be higher. > > And for a platform that doesn't yet have proper DFU suppport for > non-volatile media's, DFU to RAM can be used. > > Another minor advantage would be to increase life of mmc/nand as it > would be less used during development/testing. > > usage: ram > eg. kernel ram 0x81000000 0x1000000 > > Downloading images to RAM using DFU is not something new, this is > acheived in openmoko also. > > DFU on RAM can be used for extracting RAM contents to host using dfu > upload. Perhaps this can be extended to io for squeezing out register > dump through usb, if it is worth. > > Signed-off-by: Afzal Mohammed > Cc: Heiko Schocher > Cc: Marek Vasut > Cc: Lukasz Majewski > Cc: Pantelis Antoniou > Cc: Gerhard Sittig > Acked-by: Marek Vasut > Acked-by: Lukasz Majewski > --- > > v4: > avoid doing prefix increment in argument of simple_strtoul() > collect more tags > v3: error used instead of printf > v2: remove read/write enumerator define's, instead use new common ones > > drivers/dfu/Makefile | 1 + > drivers/dfu/dfu.c | 7 +++-- > drivers/dfu/dfu_ram.c | 77 +++++++++++++++++++++++++++++++++++++++++++++++++++ > include/dfu.h | 18 ++++++++++++ > 4 files changed, 101 insertions(+), 2 deletions(-) > create mode 100644 drivers/dfu/dfu_ram.c Thanks for this work! Hmm... minor comment. Could you add a entry in README? Beside of that: Acked-by: Heiko Schocher bye, Heiko -- DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany