Hi Rick, On Wed, Nov 21, 2018 at 4:53 PM Rick Chen <rickche...@gmail.com> wrote: > > Bin Meng <bmeng...@gmail.com> 於 2018年11月21日 週三 下午3:18寫道： > > > > Hi Rick, > > > > On Wed, Nov 21, 2018 at 2:00 PM Rick Chen <rickche...@gmail.com> wrote: > > > > > > > > > > > > > Do any of your above patches get v2 posted? At least I did not see > > > > > any follow-up > > > > > response [1] regarding to "riscv: ax25-ae350: Pass dtb address to > > > > > u-boot with a1 > > > > > register" > > > > > > First of all you told me about that > > > board_fdt_blob_setup() should be completely removed. > > > Instead the simple fix should be add CONFIG_OF_PRIOR_STAGE > > > to ax25-ae350_defconfig. > > > > > > Then I explain you about that is for booting from flash. > > > And you said > > > In this case, we need support OF_CONTROL like other arch, eg: > > > CONFIG_OF_EMBED and CONFIG_OF_SEPARATE. > > > > > > In README, I don't find the limitation about when booting from flash, > > > it can not use CONFIG_OF_BOARD. > > > > > > > Correct. However, when ax25-ae350's U-Boot boots from ROM, where does > > prior_stage_fdt_address get assigned to the ROM address? Besides, this > > variable is declared in fdtdec.h as follows: > > > > #if CONFIG_IS_ENABLED(OF_PRIOR_STAGE) > > extern phys_addr_t prior_stage_fdt_address; > > #endif > > > > It means only OF_PRIOR_STAGE will use this variable. But in your patch > > I have seen that declaration in fdtdec.h > But I was referred to > include\configs\bcmstb.h > extern phys_addr_t prior_stage_fdt_address; > and that is why I borrow prior_stage_fdt_address. >
It looks to me that bcmstb.h was an ad-hoc hack of using prior_stage_fdt_address. I don't think it was originally meant to do such. It intends to work with OF_PRIOR_STAGE only. > You do not point out this consideration directly, maybe that is why > we have some thinking is different. > Sorry I wasn't that clear, as I was expecting we continue discussing on that patch thread. > > this was borrowed to support OF_BOARD, which is confusing I think. If > > U-Boot boots from reset vector, the canonical way to support DT is via > > CONFIG_OF_EMBED or CONFIG_OF_SEPARATE. > > > > > That is why ax25-ae350 use > > > CONFIG_OF_BOARD to support boot from RAM and ROM. > > > It is a flexible approach to meet Andes' HW mechanism. > > > > > > I think it is a configuration in ax25-ae350_defconfig. > > > It will not affect qemu-riscv32(64)_defconfig. > > > > > > > I understand it does not affect qemu riscv board. The thing is that I > > wasn't clear why you did that way for ax25-ae350. > > Actually I just want to remove the redundant code in start.S > - li t0, CONFIG_SYS_SDRAM_BASE > - SREG a2, 0(t0) > so borrowed prior_stage_fdt_address in CONFIG_OF_BOARD > Regards, Bin _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de https://lists.denx.de/listinfo/u-boot
