From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Wed, 14 Nov 2001 11:08:42 +0100 From: Richard Zidlicky To: Jun Sun Cc: Roman Zippel , Geert Uytterhoeven , "Maciej W. Rozycki" , Linux/MIPS Development , Linux/m68k , Linux/PPC Development Subject: Re: [RFC] generic MIPS RTC driver Message-ID: <20011114110842.A473@linux-m68k.org> References: <3BF0371F.8040575B@linux-m68k.org> <20011113144240.B669@linux-m68k.org> <3BF15F55.AABB383C@mvista.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <3BF15F55.AABB383C@mvista.com>; from jsun@mvista.com on Tue, Nov 13, 2001 at 09:58:45AM -0800 Sender: owner-linuxppc-dev@lists.linuxppc.org List-Id: On Tue, Nov 13, 2001 at 09:58:45AM -0800, Jun Sun wrote: > Richard Zidlicky wrote: > > > Btw the interrupt need not to be hardware, for the Q40 I test > > a rtc register once per jiffie and generate a "soft interrupt". > > It could be done generic at least for m68k. > > > > I have written an experiemntal ptimer driver to do just this and potential > more. Such a device is useful for real-time programming (e.g., when you try > to implement a periodic user task). > > See http://linux.junsun.net/realtime-linux/preemption-test > > The driver is architecture independent (i.e., linux-common code) > > Due to the different programming needs behind periodic timers (or user-level > timer) and RTC operations, my vote for future work is to leave them as two > separate drivers. To me, RTC is really just to read/write RTC clock. RTC_UIE is needed (or at least very useful) to set the clock, so it belongs into a rtc driver if it can be implemented. General purpose timers are different story, btw what is wrong with setitimer that you have chosen to implement an additional driver for it? Richard ** Sent via the linuxppc-dev mail list. See http://lists.linuxppc.org/