From mboxrd@z Thu Jan 1 00:00:00 1970 From: Robert Schwebel Date: Thu, 13 Feb 2003 22:28:55 +0100 Subject: [U-Boot-Users] [ANNOUNCE] u-boot-ptx-20030213-1 In-Reply-To: <3E4C034B.9090002@in.fer.no> References: <20030213081716.GL10342@pengutronix.de> <3E4C034B.9090002@in.fer.no> Message-ID: <20030213212855.GF10342@pengutronix.de> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de On Thu, Feb 13, 2003 at 09:42:51PM +0100, Geir Thomassen wrote: > in cpu/xscale/start.S you do: > > /* test if we run from flash or RAM - RAM/BDI: don't set cpuspeed */ > /* FIXME: is the criterium used here only valid for PXA25X? */ > mov r0, pc > and r0, r0, #0xF0000000 /* RAM is at 0xa0000000-0xafffffff */ > subs r0, r0, #0xa0000000 > beq setspeed_done > > mov r0, #2 > mcr p14, 0, r0, c6, c0, 0 > setspeed_done: > > > Why? I can trace trough the CPU speed setting code without any trouble > with a BDI, and I don't understand why there should be any problems > doing so. Disabeling the CPU speed setting code without skipping the > SDRAM init code at the same time might actually get you into other > problems since the refresh periode of the SDRAM might be too long. > Jumping over the SDRAM init is a very good idea, since the code is > running from the SDRAM that the code is initializing. One important step > of the init sequence is to disable the SDRAM. The code in question was added last week and I removed it today from my local tree :-) The problem is that there is a bug in at least some hardware revisions of the PXA which in my case lets the debug handler disappear from the mini instruction cache once you access CP14 to switch the frequency. I've discussed this with the Abatron guys for some weeks now and they today have sent me a new firmware which works around the bug. It will be available officially in some days. However, as I'm now able to run the code in the debugger again the above code can be forgotten - I will not send it to Wolfgang officially. Robert -- Dipl.-Ing. Robert Schwebel | http://www.pengutronix.de Pengutronix - Linux Solutions for Science and Industry Braunschweiger Str. 79, 31134 Hildesheim, Germany Handelsregister: Amtsgericht Hildesheim, HRA 2686 Phone: +49-5121-28619-0 | Fax: +49-5121-28619-4