* Nicolas Pitre <nico@xxxxxxxxxxx> [111003 14:36]: > On Mon, 3 Oct 2011, Tony Lindgren wrote: > > > * Nicolas Pitre <nico@xxxxxxxxxxx> [111003 11:26]: > > > > OK, so let's modify omap4_panda_map_io() just to test this one board and > > > reverse the omap44xx_map_common_io() and omap2_set_globals_443x() call > > > order. Now the mappings will be there before ioremap() is called. But > > > that, too, doesn't work and the kernel now complains with: > > > > > > |OMAP revision unknown, please fix! > > > |Uninitialized omap_chip, please fix! > > > |Could not detect SRAM size > > > > > > But it looks like omap2_set_globals_tap() still has to be called first! > > > Isn't this wonderfully convoluted? > > > > We've already unravelled some of that with the init_early changes. > > > > Earlier having the IO space moving around between 2420/2430/3430 > > meant that we had to map some IO to detect the SoC. Now we have > > SoC specific initcalls where we assume the SoC category is initialized > > from board-*.c file (and from DT at some point). > > But the map_io method always has been tied to machine specific > descriptors. That always implied a fixed SoC category, no? Unless you > have a machine which can accommodate multiple different SOCs but that's > very uncommon. Hmm I think we initially tried to use board-generic.c with custom ATAGs to boot multiple SoCs and that's why we needed SoC detection for map_io. Now the only variable SoC headache left is that board-omap3beagle.c is using the same machine_id for 3430 and 3630 beagle which are somewhat different SoCs, but Luckily not from map_io point of view though. So that should be fixable with DT when the SoC type will be passed from DT. > > Having the SRAM base address move around with different sizes also > > requires the SoC detection.. Otherwise we can end up mapping wrong > > size and end up trying to access secure SRAM that will hang the system. > > > > The way to fix it is to move SRAM init happen much later so we don't > > have to map it early. I guess now we could use ioremap for SRAM, > > although we may not want device attributes for the executable code? > > Got any suggestions here on how we should map SRAM later on? > > You can use a variant of ioremap() such as __arm_ioremap() which let you > specify the memory attribute. OK, I'll take a look at that. > > > Furthermore... there is also a static mapping for physical address > > > 0x4e000000 using virtual address 0xff100000 which is already reserved > > > for other purposes i.e. the consistent DMA area. It is not immediately > > > obvious where this comes from without being intimate with the OMAP code. > > > Can this be fixed as well i.e. moved elsewhere please? > > > > This sounds like a bug somewhere. Which omap are you seeing this on? > > OMAP4430 on a Panda board. > > Here are the static mappings I'm seeing: > > phys = 0x44000000 virt = 0xf8000000 size = 0x100000 > phys = 0x4a000000 virt = 0xfc000000 size = 0x400000 > phys = 0x50000000 virt = 0xf9000000 size = 0x100000 > phys = 0x4c000000 virt = 0xfd100000 size = 0x100000 > phys = 0x4d000000 virt = 0xfe100000 size = 0x100000 > phys = 0x4e000000 virt = 0xff100000 size = 0x100000 <--- > phys = 0x48000000 virt = 0xfa000000 size = 0x400000 > phys = 0x54000000 virt = 0xfe800000 size = 0x800000 > > It is also possible that I might have screwed something up on my side. > What is located at 0x4e000000? It seems to be DMM (Dynamic Memory Manager), some more info at: http://lwn.net/Articles/417790/ Tony -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
