[EXT] Re: [EXT] Re: [PATCH v2 2/2] raspi: fixup additional vc created nodes

Denis OSTERLAND-HEIM denis.osterland at diehl.com
Tue Feb 20 23:46:33 PST 2024


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
- 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.
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.

Regards, Denis

-----Original Message-----
From: Ahmad Fatoum <a.fatoum at pengutronix.de> 
Sent: Tuesday, February 20, 2024 4:33 PM
To: Denis OSTERLAND-HEIM <denis.osterland at diehl.com>; Roland Hieber
<rhi at pengutronix.de>; Denis Osterland-Heim <denis.osterland at gmail.com>
Cc: barebox at lists.infradead.org; Alexander Dahl <ada at thorsis.com>
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 <a.fatoum at pengutronix.de>
> Sent: Monday, February 19, 2024 10:43 PM
> To: Roland Hieber <rhi at pengutronix.de>; Denis Osterland-Heim 
> <denis.osterland at gmail.com>
> Cc: barebox at lists.infradead.org; Denis OSTERLAND-HEIM 
> <denis.osterland at diehl.com>; Alexander Dahl <ada at thorsis.com>
> 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 <denis.osterland at diehl.com>
>>>
>>> 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 <denis.osterland at diehl.com>
>>> Acked-by: Ahmad Fatoum <a.fatoum at pengutronix.de>
>>> ---
>>>  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 at 7e202000.of: registered as mci0
>>     bcm2835_mci 3f300000.mmc at 7e300000.of: registered as mci1
>>     mci0: detected SD card version 2.0
>>     mci0: registered disk0
>>     state: New state registered 'state'
>>     state: Using bucket 0 at 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 |
-------------- next part --------------
A non-text attachment was scrubbed...
Name: smime.p7s
Type: application/x-pkcs7-signature
Size: 3908 bytes
Desc: not available
URL: <http://lists.infradead.org/pipermail/barebox/attachments/20240221/2e63ed69/attachment.bin>


More information about the barebox mailing list