From mboxrd@z Thu Jan 1 00:00:00 1970 From: Graeme Russ Date: Thu, 26 May 2011 07:11:02 +1000 Subject: [U-Boot] [RFC] Review of U-Boot timer API In-Reply-To: <20110525133859.C420DCEFB5B@gemini.denx.de> References: <4DD7B245.5000008@gmail.com> <201105240024.26511.vapier@gentoo.org> <4DDB42B1.2010206@emk-elektronik.de> <4DDBB29D.2050102@psyent.com> <20110524141950.2AB1CCF5DBF@gemini.denx.de> <4DDBE22D.6050806@gmail.com> <20110524191948.401CBCF5DBF@gemini.denx.de> <4DDC6F46.4090809@comcast.net> <20110525052836.11A30CF5DBF@gemini.denx.de> <20110525080837.5925BCF5DBF@gemini.denx.de> <4DDCBFF4.40002@gmail.com> <20110525113738.E49DFCFB8A4@gemini.denx.de> <4DDCED75.8030906@gmail.com> <20110525122615.DBAA4CEFB5B@gemini.denx.de> <4DDCF926.1050904@gmail.com> <20110525125903.3C517CEFB5B@gemini.denx.de> <20110525133859.C420DCEFB5B@gemini.denx.de> Message-ID: <4DDD7066.4000505@gmail.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de On 25/05/11 23:38, Wolfgang Denk wrote: > Dear Graeme Russ, > > In message you wrote: >> >> And what about platforms that do not support interrupts? Are you >> mandating that get_timer() MUST always be supported by a timer updated >> by an ISR? > > No, not at all. And I already answered this. For example on PPC, just > reading the timebase would be perfectly sufficient, and simpler and > more reliable than the current interrupt based approach. I assume by 'timebase' you mean the 64-bit tick counter. If so, that is _exactly_ what I am suggesting we do (and what does already happen on ARM). The big change is, the prescaler is common code rather than haven dozens (some of them broken) implementations Regards, Graeme