On 4/11/22 09:05, Ashish Mhetre wrote: > > > On 4/10/2022 7:48 PM, Dmitry Osipenko wrote: >> External email: Use caution opening links or attachments >> >> >> 06.04.2022 08:24, Ashish Mhetre пишет: >>> + num_dt_channels = >>> of_property_count_elems_of_size(pdev->dev.of_node, "reg", >>> + reg_cells * >>> sizeof(u32)); >>> + /* >>> + * On tegra186 onwards, memory controller support multiple >>> channels. >>> + * Apart from regular memory controller channels, there is one >>> broadcast >>> + * channel and one for stream-id registers. >>> + */ >>> + if (num_dt_channels < mc->soc->num_channels + 2) { >>> + dev_warn(&pdev->dev, "MC channels are missing, please >>> update memory controller DT node with MC channels\n"); >>> + return 0; >>> + } >>> + >>> + mc->bcast_ch_regs = devm_platform_ioremap_resource_byname(pdev, >>> "mc-broadcast"); >>> + if (IS_ERR(mc->bcast_ch_regs)) >>> + return PTR_ERR(mc->bcast_ch_regs); >> >> Looks to me that you don't need to use of_property_count_elems_of_size() >> and could only check the "mc-broadcast" presence to decide whether this >> is an older DT. >> > Now that we are using reg-names in new DT, yes it'd be fine to just > check mc-broadcast to decide it's a new or old DT. > >> mc->bcast_ch_regs = devm_platform_ioremap_resource_byname(pdev, >> "broadcast"); >> if (IS_ERR(mc->bcast_ch_regs)) { >> dev_warn(&pdev->dev, "Broadcast channel is missing, please >> update your >> device-tree\n"); >> return PTR_ERR(mc->bcast_ch_regs); >> } > > return 0; > > to avoid DT ABI break, right? Yes, it should be "return 0".