From mboxrd@z Thu Jan 1 00:00:00 1970 From: Wolfgang Wegner Date: Sat, 24 Apr 2010 11:45:49 +0200 Subject: [U-Boot] [PATCH RFC v3] add CONFIG_BOOTCOUNT_LIMIT for MCF5445x In-Reply-To: <20100423222742.B61FA1EC6E@gemini.denx.de> References: <1272026324-18566-1-git-send-email-w.wegner@astro-kom.de> <20100423192535.23CF519F60@gemini.denx.de> <20100423194341.GS20047@leila.ping.de> <20100423200332.E99F119F60@gemini.denx.de> <20100423202642.GT20047@leila.ping.de> <20100423204753.2618E24FA1@gemini.denx.de> <20100423205938.GU20047@leila.ping.de> <20100423222742.B61FA1EC6E@gemini.denx.de> Message-ID: <20100424094548.GW20047@leila.ping.de> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Dear Wolfgang Denk, On Sat, Apr 24, 2010 at 12:27:42AM +0200, Wolfgang Denk wrote: > Dear Wolfgang Wegner, > > In message <20100423205938.GU20047@leila.ping.de> you wrote: > > This patch adds bootcount for Freescale MCF5445x. Two registers of > > eDMA transfer control descriptors (TCD[1]) are used because these > > are unused by linux kernel (freescale LTIB linux-2.6.25) and were > > tested to keep their contents across resets. > > TCD[1] is currently unused by the linux drivers, so using its registers > > should be safe as long as no non-standard driver is loaded. > > > > Signed-off-by: Wolfgang Wegner > > --- > > I implemented and tested this bootcount on a custom MCF54455 board. > > According to the data sheet, the internal SRAM is not supposed to be > > useful for data storage across resets. There is no explicit statement > > concerning the TCD registers, but in tests on our board the values > > did always survive reset. > > v2: updated comment > > v3: moved updated comment to the right place :-) > > Did you??? The part about how long the registers are untouched by other drivers - yes. The other part not. Originally the other part of the comment was more or less meant to be a hint for others (probably having more experience with coldfire than me) reviewing the patch, so that I could afterwards provide a completely revised version. Looking at it today, I should simply have moved everything up to the commit message, but as it is now, I should probably simply wait to let others comment before sending another patch? Best regards, Wolfgang