On 04/08/2021 23:30, Sam Protsenko wrote: >>> >>> Nice catch! Actually there is an error (typo?) in SoC's TRM, saying >>> that Virtual Interface Control Register starts at 0x3000 offset (from >>> 0x12a00000), where it obviously should be 0x4000, that's probably >>> where this dts error originates from. Btw, I'm also seeing the same >>> error in exynos7.dtsi. >> >> What's the error exactly? The "Virtual interface control register" >> offset (3rd region) is set properly to 0x4000 on Exynos7. Also one for >> the Exynos5433 looks correct. >> > > The issue is that 2nd region's size is 0x1000, but it must be 0x2000. > It's defined by GIC-400 architecture, as I understand. Please look at > [1], table 3-1 has very specific offsets and sizes for each functional > block, and each particular SoC must adhere to that spec. So having > 0x1000 for 2nd region can't be correct. And because exynos7.dtsi has > GIC-400 as well, and 0x1000 is specified there for 2nd region size > too, so I presume there is the same mistake there. I understand, the range length has indeed same mistake. However it does not matter that much There are no registers pass 0x10C (so pass 0x1000). This address space is not used. > Can you please check the TRM for Exynos7 SoC (if you have one in your > possession), and see if there is a typo there? E.g. in case of > Exynos850 TRM I can see that in "Register Map Summary" section the > offset for the first register (GICH_HCR) in "Virtual Interface Control > Register" region is specified as 0x3000, where it should be 0x4000, so > it's probably a typo. But the register description is correct, saying > that: "Address = Base Address + 0x4000". The starting addresses of each registers range is different issue and this one matters. Except same typo as you say, all looks good - they start at 0x4000. > > [1] https://developer.arm.com/documentation/ddi0471/b/programmers-model/gic-400-register-map > >>> Though I don't have a TRM for Exynos7 SoCs, so >>> not sure if I should go ahead and fix that too. Anyway, for Exynos850, >>> I'll fix that in v2 series. >> >> >> However while we are at addresses - why are you using address-cells 2? >> It adds everywhere additional 0x0 before actual address. >> > > Right. For "cpus" node I'll change the address-cells to 1 in my v2 > series. I'll keep address-cells=2 for the root node, but I'm going to > encapsulate some nodes into soc node (as you suggested earlier), where > I'll make address-cells=1. That's pretty much how it's done in > exynos7.dtsi and in exynos5433.dtsi, so I guess that's should be fine > (to get rid of superfluous 0x0 and conform with other Exynos DTs)? Yes, thanks. Best regards, Krzysztof
