Hi, Well, the kernel in root A may have a different device tree, than the one in root B. This is the kernel version update case. What would break, depends on the changes to the dt. Regards, Denis -----Original Message----- From: Ahmad Fatoum Sent: Monday, February 26, 2024 1:39 PM To: Denis OSTERLAND-HEIM ; Roland Hieber ; Denis Osterland-Heim Cc: barebox@lists.infradead.org; Alexander Dahl Subject: [EXT] Re: [EXT] Re: [EXT] Re: [PATCH v2 2/2] raspi: fixup additional vc created nodes [EXTERNAL EMAIL] Hello Denis, On 21.02.24 08:46, Denis OSTERLAND-HEIM wrote: > Hi, > > It took me a while to think about it. > First I would like to explain my current boot process and then how I > think it would like with your suggestion. > > > Now: > > Disk layout: > - rpi boot fat: dt-2nd.img, barebox-dts, rpi-elf, config.txt > - root A > - root B > > Boot process: > - rpi boot loader > * load dt-2nd.img and dt > * read Hat Eeprom > * apply fixups to dt > - barebox with dt from r2 > * bootchooser select A or B > * load kernel and dt from A or B > * copy stuff to kernel dt from barebox internal dt as fixups > - linux boot > > > Your approach: > > Disk layout: > - rpi boot fat: bb-rpi.img, some-dts, rpi-elf, config.txt > - root A > - root B > > Boot process: > - rpi boot loader > * load bb-rpi.img and dt > * read Hat Eeprom > * apply fixups to dt > - barebox with built-in dt > * bootchooser select A or B > * load kernel and dt from A or B > * copy stuff to kernel dt from /vc.dtb as fixups This I don't understand. Why not use vc.dtb as kernel DT? You can still have barebox apply boot arg fixups and so on, but use /vc.dtb as base? > - linux boot > > I can remember that I tried to implement the fixups as script in the > environment first, but switched to C somewhen. > I can not recall the reason, sorry. > I guess it was related to recursive copy. > The C code uses of_merge_node or something like that, which is not > available as command, I think. This can be made available to shell too if there's use for it, but I think this is tangential. > If we can keep the patches an just do something like if /vc.dtb then > apply fixups, I would be fine with your approach. > But I guess this almost exactly matches the `if(!IS_ERR(root)) > rpi_vc_fdt_parse(root);` approach. > If you just revert the patches, I guess I would have to find a way to > do it in script. What would break if you used vc.dtb as kernel DT? Thanks, Ahmad > > Regards, Denis > > -----Original Message----- > From: Ahmad Fatoum > Sent: Tuesday, February 20, 2024 4:33 PM > To: Denis OSTERLAND-HEIM ; Roland Hieber > ; Denis Osterland-Heim > Cc: barebox@lists.infradead.org; Alexander Dahl > Subject: [EXT] Re: [EXT] Re: [PATCH v2 2/2] raspi: fixup additional vc > created nodes > > [EXTERNAL EMAIL] > > > Hello Denis, > > On 20.02.24 09:16, Denis OSTERLAND-HEIM wrote: >> Hi, >> >> I think so, too. >> I think that my mistake was in 5ea6e19737e10973ce2cf785970e32562d9ee8f1. > > Yes. > >>> @@ -379,17 +381,17 @@ static void rpi_vc_fdt(void) >>> if (oftree->totalsize) >>> pr_err("there was an error copying fdt in pbl: >> %d\n", >>> be32_to_cpu(oftree->totalsize)); >>> - return; >> This return previously avoided a call of rpi_vc_fdt_parse(). >> > > [snip] > >>> rpi_env_init(); >>> - rpi_vc_fdt(); >>> + root = rpi_vc_fdt(); >>> + rpi_vc_fdt_parse(IS_ERR(root) ? priv->dev->device_node : root); >> Now rpi_vc_fdt_parse() is called in both cases. >> So, it should be: >> if (!IS_ERR(root)) >> rpi_vc_fdt_parse(root); >>> rpi_set_kernel_name(); >>> >> ... >> >> Or do I miss something? > > Now that I think of it, I think the commit should just be reverted. > I don't see the utility of using barebox-dt-2nd.img on the Raspberry Pi: > > - If the board is already supported, use barebox-raspberry-pi.img, which > has the DT built-in. > > - If the board is not supported , use barebox-raspberry-pi.img, which > will take the outside DT and save it where the board code expects it. > > What do you think? > > Thanks, > Ahmad > >> >> Regards, Denis >> >> -----Original Message----- >> From: Ahmad Fatoum >> Sent: Monday, February 19, 2024 10:43 PM >> To: Roland Hieber ; Denis Osterland-Heim >> >> Cc: barebox@lists.infradead.org; Denis OSTERLAND-HEIM >> ; Alexander Dahl >> Subject: [EXT] Re: [PATCH v2 2/2] raspi: fixup additional vc created >> nodes >> >> [EXTERNAL EMAIL] >> >> >> Hello Roland, >> >> On 19.02.24 20:14, Roland Hieber wrote: >>> Hi, >>> >>> On Mon, Sep 25, 2023 at 01:10:05PM +0200, Denis Osterland-Heim wrote: >>>> From: Denis OSTERLAND-HEIM >>>> >>>> The video core creates some additional nodes. >>>> This code takes over this values. >>>> The /hat node is only there if an raspi hat with EEPROM is detected. >>>> >>>> Signed-off-by: Denis OSTERLAND-HEIM >>>> Acked-by: Ahmad Fatoum >>>> --- >>>>  arch/arm/boards/raspberry-pi/rpi-common.c | 39 >>>> +++++++++++++++++------ >>>>  1 file changed, 30 insertions(+), 9 deletions(-) >>>> >>>> diff --git a/arch/arm/boards/raspberry-pi/rpi-common.c >>>> b/arch/arm/boards/raspberry-pi/rpi-common.c >>>> index ceafd55a56..713fad78c9 100644 >>>> --- a/arch/arm/boards/raspberry-pi/rpi-common.c >>>> +++ b/arch/arm/boards/raspberry-pi/rpi-common.c >>>> @@ -264,19 +264,37 @@ static enum reset_src_type >>>> rpi_decode_pm_rsts(struct device_node *chosen, >>>>   >>>>  static int rpi_vc_fdt_fixup(struct device_node *root, void *data) >>>>  { >>>> -       const struct device_node *vc_chosen = data; >>>> -       struct device_node *chosen; >>>> +       const struct device_node *vc_node = data; >>>> +       struct device_node *node; >>>> +       struct property *pp; >>>>   >>>> -       chosen = of_create_node(root, "/chosen"); >>>> -       if (!chosen) >>>> +       node = of_create_node(root, vc_node->full_name); >>>> +       if (!node) >>>>                 return -ENOMEM; >>>>   >>>> -       of_copy_property(vc_chosen, "overlay_prefix", chosen); >>>> -       of_copy_property(vc_chosen, "os_prefix", chosen); >>>> +       for_each_property_of_node(vc_node, pp) >>>> +               of_copy_property(vc_node, pp->name, node); >>>>   >>>>         return 0; >>>>  } >>>>   >>>> +static struct device_node *register_vc_fixup(struct device_node >>>> +*root, >>>> +                                            const char *path) { >>>> +       struct device_node *ret, *tmp; >>>> + >>>> +       ret = of_find_node_by_path_from(root, path); >>>> +       if (ret) { >>>> +               tmp = of_dup(ret); >>>> +               tmp->full_name = xstrdup(ret->full_name); >>>> +               of_register_fixup(rpi_vc_fdt_fixup, tmp); >>>> +       } else { >>>> +               pr_info("no '%s' node found in vc fdtn", path); >>>> +       } >>>> + >>>> +       return ret; >>>> +} >>>> + >>>>  static u32 rpi_boot_mode, rpi_boot_part; >>>>  /* Extract useful information from the VideoCore FDT we got. >>>>   * Some parameters are defined here: >>>> @@ -300,14 +318,17 @@ static void rpi_vc_fdt_parse(struct >>>> device_node >>>> *root) >>>>                 free(str); >>>>         } >>>>   >>>> -       chosen = of_find_node_by_path_from(root, "/chosen"); >>>> +       register_vc_fixup(root, "/system"); >>>> +       register_vc_fixup(root, "/axi"); >>>> +       register_vc_fixup(root, "/reserved-memory"); >>>> +       register_vc_fixup(root, "/hat"); >>>> +       register_vc_fixup(root, "/chosen/bootloader"); >>>> +       chosen = register_vc_fixup(root, "/chosen"); >>> >>> This throws a lot of new warnings and errors on our RPi 3B: >>> >>> barebox 2024.01.0 #1 2024-02-01T00:00:00+00:00 >>> Buildsystem version: DistroKit-2019.12.0-552-g775624b9f5d6 >>> >>> Board: Raspberry Pi 3 Model B >>> deep-probe: supported due to raspberrypi,3-model-b >>> netconsole: registered as netconsole-1 >>> bcm2835-sdhost 3f202000.mmc@7e202000.of: registered as mci0 >>> bcm2835_mci 3f300000.mmc@7e300000.of: registered as mci1 >>> mci0: detected SD card version 2.0 >>> mci0: registered disk0 >>> state: New state registered 'state' >>> state: Using bucket 0@0x00000000 >>> malloc space: 0x1d87f620 -> 0x3b0fec3f (size 472.5 MiB) >>> WARNING: no property 'serial-number' found in vc fdt's '' node >>> no '/system' node found in vc fdt >>> no '/axi' node found in vc fdt >>> no '/hat' node found in vc fdt >>> no '/chosen/bootloader' node found in vc fdt >>> WARNING: no property 'bootargs' found in vc fdt's '/chosen' node >>> WARNING: no property 'overlay_prefix' found in vc fdt's '/chosen' > node >>> WARNING: no property 'os_prefix' found in vc fdt's '/chosen' node >>> WARNING: 'pm_rsts' value not found in vc fdt >>> ERROR: Won't delete root device node >>> environment load /boot/barebox.env: No such file or directory >>> Maybe you have to create the partition. >>> >>> Do you have any idea what is going on here? >>> >>> I also don't see /vc.dtb, which should have been created. I have >>> 'vc.kernel: kernel7.img' in the 'global' output, but nothing else >>> starting with vc.*. >> >> I think that a non-existent /vc.dtb is expected if there's no DTs in >> the boot partition as is the case with DistroKit (except for rpi4) or >> if using barebox-dt-2nd.img. >> >> I think the info/warning messages should just be dropped. >> >> Cheers, >> Ahmad >> >>> >>> - Roland >>> >>>>         if (!chosen) { >>>>                 pr_err("no '/chosen' node found in vc fdtn"); >>>>                 goto out; >>>>         } >>>>   >>>> -       of_register_fixup(rpi_vc_fdt_fixup, of_dup(chosen)); >>>> - >>>>         bootloader = of_find_node_by_name(chosen, "bootloader"); >>>>   >>>>         str = of_read_vc_string(chosen, "bootargs"); >>>> -- >>>> 2.39.2 >>>> >>>> >>> >> > -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |