On 4/22/19 8:22 PM, Simon Goldschmidt wrote: > Am 22.04.2019 um 20:01 schrieb Marek Vasut: >> On 4/19/19 10:00 PM, Simon Goldschmidt wrote: >>> >>> >>> On 17.04.19 22:15, Marek Vasut wrote: >>>> Add optional "mask" argument to the SoCFPGA bridge command, to select >>>> which bridges should be enabled/disabled. This allows the user to avoid >>>> enabling bridges which are not connected into the FPGA fabric. Default >>>> behavior is to enable/disable all bridges. >>> >>> So does this change the command? Seems like leaving away the new 'mask' >>> argument would now lead to enabling all bridges by overwriting whatever >>> the handoff values were before? >> >> That's how it behaved before though -- all the bridges were enabled. >> Now it's possible to explicitly select which bridges to enable/disable. > > As I read the code, before it wrote iswgrp_handoff[x] to the registers.
Nope, before it was the SPL that wrote the iswgrp_handoff registers (iswgrp_handoff[0] to 0x0 and iswgrp_handoff[1] to 0x7) > The question is what is iswgrp_handoff[x]. Just regular scratch registers with special name. The [0] is used to indicate to the software how the brg_mod_reset register is supposed to be configured. The [1] is used to indicate how the l3remap register is supposed to be configured. The SPL currently sets these registers as -- all bridges released out of reset ; all bridges mapped into the L3 space. I believe this patch does not change that behavior. > It's not the bridges status > from Quartus (as the "handoff" suffix might suggest). Instead (if I > remember correctly), it's either "all bridges" or "no bridges", > depending on the FPGA configuration status at SPL runtime. > > In this case, we're probably better off with leaving it to the command > line scripts to say which bridges shall be enabled... This patch only changes things in that it updates the handoff registers when the user selects a new mask, so that any software which runs after U-Boot would be aware of which bridges U-Boot configured. But maybe I'm missing something obvious, this stuff is so convoluted that I'd really appreciate if you could review thoroughly if there's something that doesn't seem right. > Reviewed-by: Simon Goldschmidt <simon.k.r.goldschm...@gmail.com> > > -- Best regards, Marek Vasut _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de https://lists.denx.de/listinfo/u-boot