Date: Tue, 03 Apr 2007 13:54:19 -0600 (MDT) From: Warner Losh <imp@bsdimp.com> To: ticso@cicely.de, ticso@cicely12.cicely.de Cc: freebsd-arm@FreeBSD.org Subject: Re: adding 16550 UART to RM9200 Message-ID: <20070403.135419.74695322.imp@bsdimp.com> In-Reply-To: <20070403185553.GS80382@cicely12.cicely.de> References: <20070403154858.GR80382@cicely12.cicely.de> <20070403.100732.74697496.imp@bsdimp.com> <20070403185553.GS80382@cicely12.cicely.de>
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> I might consider running only 3 boards on IRQ0 and the other 3 on IRQ3. > Although the RM9200 has 7 external interrupts (not counting FIQ), the > remaining IRQ* all collide :( > - IRQ0 unshared > - IRQ1 TWCK needed for my external RTC > - IRQ2 TWD same as above > - IRQ3 TXD2 I can easily accept loosing this UART with the new ones > - IRQ4 SPCK needed for dataflash booting and I don't want to switch to > iic-eeprom for booting > - IRQ5 NPCS0 same as above > - IRQ6 Ethernet MDIO > > I could free 2 IRQ if I either run without IIC or SPI, but this still > wouldn't give me the ideal of 6 lines. Have you considered just using a GPIO pin for this and routing the interrupt that way? There's code there now to cope with the change of level in the GPIO pins. That way you'd only have to read one register and mask out the pins you want. The only mild gotcha here is that the interrupt is for signal change, not for a level, iirc. Surely you haven't used up all the I/O lines. > Is pmap_mapdev useable as Olivier wrote and this comment is outdated? No. that's fine. > Or is there still a problem with AT91? It is OK. > All in all this is just a single page to be mapped, which won't hurt, > so pmap_mapdev sounds good. OK. The other way maps it always, but maybe it would be better the simpler way. The above table maps to calls to pmap_mapdev anyway. > > I'm starting to think that we may be getting to the point where we > > need to do better board support in this subport. You are making too > > many of them too quickly and it is straining the infrastructure :-) > > Consider, that the daughter boards all get generic bus access and don't > really have to be UART ones... heh... Warner P.S. You never answered my question about giving me one :-) that's OK, it was a joke anyway.
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