* [PATCH] distro_bootcmd: change the default dtb search path to include default kernel dtbs directory
@ 2021-09-17 11:02 Qu Wenruo
2021-09-17 11:34 ` Mark Kettenis
0 siblings, 1 reply; 5+ messages in thread
From: Qu Wenruo @ 2021-09-17 11:02 UTC (permalink / raw)
To: u-boot
When booting using U-boot -> systemd-boot (EFI payload) -> kernel on
RK3399, systemd-boot by some bug can't execute its "devicetree" key
correctly to load its proper dtb from files.
In that case, it will use fallback dtb from U-boot, which can be
out-of-date, and on RK3399, even the latest U-boot contains out-of-date
dtb which can cause problems like invalid opp tables.
And for systemd-boot, it doesn't provide any board specific dtb, but
completely relies on the EFI environment provided by U-boot, thus if we
can't find a good dtb, the fallback one will be used anyway.
So this patch will workaround the problem by appending common linux dtbs
directory to the existing "efi_dtb_prefixes" so that for systemd-boot it
can use the existing fdt and boot properly.
Signed-off-by: Qu Wenruo <wqu@suse.com>
---
include/config_distro_bootcmd.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/include/config_distro_bootcmd.h b/include/config_distro_bootcmd.h
index 2627c2a6a541..4ec87483eb65 100644
--- a/include/config_distro_bootcmd.h
+++ b/include/config_distro_bootcmd.h
@@ -151,7 +151,7 @@
"load ${devtype} ${devnum}:${distro_bootpart} " \
"${fdt_addr_r} ${prefix}${efi_fdtfile}\0" \
\
- "efi_dtb_prefixes=/ /dtb/ /dtb/current/\0" \
+ "efi_dtb_prefixes=/ /dtb/ /dtb/current/ /dtbs/ /dtbs/current/\0" \
"scan_dev_for_efi=" \
"setenv efi_fdtfile ${fdtfile}; " \
BOOTENV_EFI_SET_FDTFILE_FALLBACK \
--
2.33.0
^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [PATCH] distro_bootcmd: change the default dtb search path to include default kernel dtbs directory
2021-09-17 11:02 [PATCH] distro_bootcmd: change the default dtb search path to include default kernel dtbs directory Qu Wenruo
@ 2021-09-17 11:34 ` Mark Kettenis
2021-09-17 11:42 ` Qu Wenruo
0 siblings, 1 reply; 5+ messages in thread
From: Mark Kettenis @ 2021-09-17 11:34 UTC (permalink / raw)
To: Qu Wenruo; +Cc: u-boot
> From: Qu Wenruo <wqu@suse.com>
> Date: Fri, 17 Sep 2021 19:02:35 +0800
>
> When booting using U-boot -> systemd-boot (EFI payload) -> kernel on
> RK3399, systemd-boot by some bug can't execute its "devicetree" key
> correctly to load its proper dtb from files.
>
> In that case, it will use fallback dtb from U-boot, which can be
> out-of-date, and on RK3399, even the latest U-boot contains out-of-date
> dtb which can cause problems like invalid opp tables.
>
> And for systemd-boot, it doesn't provide any board specific dtb, but
> completely relies on the EFI environment provided by U-boot, thus if we
> can't find a good dtb, the fallback one will be used anyway.
>
> So this patch will workaround the problem by appending common linux dtbs
> directory to the existing "efi_dtb_prefixes" so that for systemd-boot it
> can use the existing fdt and boot properly.
Why isn't the dtb installed in the standard location?
Slowing the boot process down because distro's can't agree where to
put the files is a bit lame...
> Signed-off-by: Qu Wenruo <wqu@suse.com>
> ---
> include/config_distro_bootcmd.h | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/include/config_distro_bootcmd.h b/include/config_distro_bootcmd.h
> index 2627c2a6a541..4ec87483eb65 100644
> --- a/include/config_distro_bootcmd.h
> +++ b/include/config_distro_bootcmd.h
> @@ -151,7 +151,7 @@
> "load ${devtype} ${devnum}:${distro_bootpart} " \
> "${fdt_addr_r} ${prefix}${efi_fdtfile}\0" \
> \
> - "efi_dtb_prefixes=/ /dtb/ /dtb/current/\0" \
> + "efi_dtb_prefixes=/ /dtb/ /dtb/current/ /dtbs/ /dtbs/current/\0" \
> "scan_dev_for_efi=" \
> "setenv efi_fdtfile ${fdtfile}; " \
> BOOTENV_EFI_SET_FDTFILE_FALLBACK \
> --
> 2.33.0
>
>
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] distro_bootcmd: change the default dtb search path to include default kernel dtbs directory
2021-09-17 11:34 ` Mark Kettenis
@ 2021-09-17 11:42 ` Qu Wenruo
2021-09-17 14:25 ` Mark Kettenis
0 siblings, 1 reply; 5+ messages in thread
From: Qu Wenruo @ 2021-09-17 11:42 UTC (permalink / raw)
To: Mark Kettenis, Qu Wenruo; +Cc: u-boot
On 2021/9/17 19:34, Mark Kettenis wrote:
>> From: Qu Wenruo <wqu@suse.com>
>> Date: Fri, 17 Sep 2021 19:02:35 +0800
>>
>> When booting using U-boot -> systemd-boot (EFI payload) -> kernel on
>> RK3399, systemd-boot by some bug can't execute its "devicetree" key
>> correctly to load its proper dtb from files.
>>
>> In that case, it will use fallback dtb from U-boot, which can be
>> out-of-date, and on RK3399, even the latest U-boot contains out-of-date
>> dtb which can cause problems like invalid opp tables.
>>
>> And for systemd-boot, it doesn't provide any board specific dtb, but
>> completely relies on the EFI environment provided by U-boot, thus if we
>> can't find a good dtb, the fallback one will be used anyway.
>>
>> So this patch will workaround the problem by appending common linux dtbs
>> directory to the existing "efi_dtb_prefixes" so that for systemd-boot it
>> can use the existing fdt and boot properly.
>
> Why isn't the dtb installed in the standard location?
Isn't standard location "/dtbs" other than "/dtb"?
At least kernel puts its dtbs into "/dtbs" by default.
>
> Slowing the boot process down because distro's can't agree where to
> put the files is a bit lame...
Would it be better to make the search path configurable at config time?
By that each distro should config their dtbs search path, which could
further optimize the boot sequence by removing all other unnecessary
prefixes.
Thanks,
Qu
>
>> Signed-off-by: Qu Wenruo <wqu@suse.com>
>> ---
>> include/config_distro_bootcmd.h | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/include/config_distro_bootcmd.h b/include/config_distro_bootcmd.h
>> index 2627c2a6a541..4ec87483eb65 100644
>> --- a/include/config_distro_bootcmd.h
>> +++ b/include/config_distro_bootcmd.h
>> @@ -151,7 +151,7 @@
>> "load ${devtype} ${devnum}:${distro_bootpart} " \
>> "${fdt_addr_r} ${prefix}${efi_fdtfile}\0" \
>> \
>> - "efi_dtb_prefixes=/ /dtb/ /dtb/current/\0" \
>> + "efi_dtb_prefixes=/ /dtb/ /dtb/current/ /dtbs/ /dtbs/current/\0" \
>> "scan_dev_for_efi=" \
>> "setenv efi_fdtfile ${fdtfile}; " \
>> BOOTENV_EFI_SET_FDTFILE_FALLBACK \
>> --
>> 2.33.0
>>
>>
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] distro_bootcmd: change the default dtb search path to include default kernel dtbs directory
2021-09-17 11:42 ` Qu Wenruo
@ 2021-09-17 14:25 ` Mark Kettenis
2021-09-17 14:29 ` Qu Wenruo
0 siblings, 1 reply; 5+ messages in thread
From: Mark Kettenis @ 2021-09-17 14:25 UTC (permalink / raw)
To: Qu Wenruo; +Cc: wqu, u-boot
> Date: Fri, 17 Sep 2021 19:42:29 +0800
> Content-Language: en-US
>
> On 2021/9/17 19:34, Mark Kettenis wrote:
> >> From: Qu Wenruo <wqu@suse.com>
> >> Date: Fri, 17 Sep 2021 19:02:35 +0800
> >>
> >> When booting using U-boot -> systemd-boot (EFI payload) -> kernel on
> >> RK3399, systemd-boot by some bug can't execute its "devicetree" key
> >> correctly to load its proper dtb from files.
> >>
> >> In that case, it will use fallback dtb from U-boot, which can be
> >> out-of-date, and on RK3399, even the latest U-boot contains out-of-date
> >> dtb which can cause problems like invalid opp tables.
> >>
> >> And for systemd-boot, it doesn't provide any board specific dtb, but
> >> completely relies on the EFI environment provided by U-boot, thus if we
> >> can't find a good dtb, the fallback one will be used anyway.
> >>
> >> So this patch will workaround the problem by appending common linux dtbs
> >> directory to the existing "efi_dtb_prefixes" so that for systemd-boot it
> >> can use the existing fdt and boot properly.
> >
> > Why isn't the dtb installed in the standard location?
>
> Isn't standard location "/dtbs" other than "/dtb"?
>
> At least kernel puts its dtbs into "/dtbs" by default.
Hmm, well, when I Alexander Graf introduced the code to load an
updated DTB the intention was clearly to load it from the EFI System
Partition (ESP). I doubt that's where "the kernel" sticks them by
default. So I suspect the intention is that you copy the DTB to the
/dtb directory on the ESP if needed. Clearly that isn't what you've
done on your system.
I suspect things have moved on a bit as the discussion in the systemd
thread shows. One of the new developments is the EFI_DT_FIXUP_PROCOL
feature that is clearly targeted at EFI bootloaders picking and
loading the DT instead of U-Boot.
In this light I would be somewhat reluctant adding more directories to
efi_dtb_prefixes.
> > Slowing the boot process down because distro's can't agree where to
> > put the files is a bit lame...
>
> Would it be better to make the search path configurable at config time?
>
> By that each distro should config their dtbs search path, which could
> further optimize the boot sequence by removing all other unnecessary
> prefixes.
Not in my opinion. I consider it a bad thing if people configure
U-Boot specifically for their distro. The whole idea of distroboot
and EFI in U-Boot is to be able to boot just any OS with a generic
U-Boot binary.
> Thanks,
> Qu
>
> >
> >> Signed-off-by: Qu Wenruo <wqu@suse.com>
> >> ---
> >> include/config_distro_bootcmd.h | 2 +-
> >> 1 file changed, 1 insertion(+), 1 deletion(-)
> >>
> >> diff --git a/include/config_distro_bootcmd.h b/include/config_distro_bootcmd.h
> >> index 2627c2a6a541..4ec87483eb65 100644
> >> --- a/include/config_distro_bootcmd.h
> >> +++ b/include/config_distro_bootcmd.h
> >> @@ -151,7 +151,7 @@
> >> "load ${devtype} ${devnum}:${distro_bootpart} " \
> >> "${fdt_addr_r} ${prefix}${efi_fdtfile}\0" \
> >> \
> >> - "efi_dtb_prefixes=/ /dtb/ /dtb/current/\0" \
> >> + "efi_dtb_prefixes=/ /dtb/ /dtb/current/ /dtbs/ /dtbs/current/\0" \
> >> "scan_dev_for_efi=" \
> >> "setenv efi_fdtfile ${fdtfile}; " \
> >> BOOTENV_EFI_SET_FDTFILE_FALLBACK \
> >> --
> >> 2.33.0
> >>
> >>
>
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] distro_bootcmd: change the default dtb search path to include default kernel dtbs directory
2021-09-17 14:25 ` Mark Kettenis
@ 2021-09-17 14:29 ` Qu Wenruo
0 siblings, 0 replies; 5+ messages in thread
From: Qu Wenruo @ 2021-09-17 14:29 UTC (permalink / raw)
To: Mark Kettenis; +Cc: wqu, u-boot
On 2021/9/17 22:25, Mark Kettenis wrote:
>> Date: Fri, 17 Sep 2021 19:42:29 +0800
>> Content-Language: en-US
>>
>> On 2021/9/17 19:34, Mark Kettenis wrote:
>>>> From: Qu Wenruo <wqu@suse.com>
>>>> Date: Fri, 17 Sep 2021 19:02:35 +0800
>>>>
>>>> When booting using U-boot -> systemd-boot (EFI payload) -> kernel on
>>>> RK3399, systemd-boot by some bug can't execute its "devicetree" key
>>>> correctly to load its proper dtb from files.
>>>>
>>>> In that case, it will use fallback dtb from U-boot, which can be
>>>> out-of-date, and on RK3399, even the latest U-boot contains out-of-date
>>>> dtb which can cause problems like invalid opp tables.
>>>>
>>>> And for systemd-boot, it doesn't provide any board specific dtb, but
>>>> completely relies on the EFI environment provided by U-boot, thus if we
>>>> can't find a good dtb, the fallback one will be used anyway.
>>>>
>>>> So this patch will workaround the problem by appending common linux dtbs
>>>> directory to the existing "efi_dtb_prefixes" so that for systemd-boot it
>>>> can use the existing fdt and boot properly.
>>>
>>> Why isn't the dtb installed in the standard location?
>>
>> Isn't standard location "/dtbs" other than "/dtb"?
>>
>> At least kernel puts its dtbs into "/dtbs" by default.
>
> Hmm, well, when I Alexander Graf introduced the code to load an
> updated DTB the intention was clearly to load it from the EFI System
> Partition (ESP). I doubt that's where "the kernel" sticks them by
> default. So I suspect the intention is that you copy the DTB to the
> /dtb directory on the ESP if needed. Clearly that isn't what you've
> done on your system.
Well, for this U-boot > systemd-boot > kernel loading scheme,
systemd-boot is responsible to load the fdt.
But for now (the latest stable release), it doesn't support fdt loading
at all, and only recently get the ability:
https://github.com/systemd/systemd/pull/19417
So in theory, it doesn't need any fdt for systemd-boot.
It's more like a workaround (and not really needed now).
>
> I suspect things have moved on a bit as the discussion in the systemd
> thread shows. One of the new developments is the EFI_DT_FIXUP_PROCOL
> feature that is clearly targeted at EFI bootloaders picking and
> loading the DT instead of U-Boot.
Yep, I didn't notice the development in systemd part.
>
> In this light I would be somewhat reluctant adding more directories to
> efi_dtb_prefixes.
Yeah, please discard the patch, it's really a workaround and not needed
anymore.
Thanks,
Qu
>
>>> Slowing the boot process down because distro's can't agree where to
>>> put the files is a bit lame...
>>
>> Would it be better to make the search path configurable at config time?
>>
>> By that each distro should config their dtbs search path, which could
>> further optimize the boot sequence by removing all other unnecessary
>> prefixes.
>
> Not in my opinion. I consider it a bad thing if people configure
> U-Boot specifically for their distro. The whole idea of distroboot
> and EFI in U-Boot is to be able to boot just any OS with a generic
> U-Boot binary.
>
>> Thanks,
>> Qu
>>
>>>
>>>> Signed-off-by: Qu Wenruo <wqu@suse.com>
>>>> ---
>>>> include/config_distro_bootcmd.h | 2 +-
>>>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>>>
>>>> diff --git a/include/config_distro_bootcmd.h b/include/config_distro_bootcmd.h
>>>> index 2627c2a6a541..4ec87483eb65 100644
>>>> --- a/include/config_distro_bootcmd.h
>>>> +++ b/include/config_distro_bootcmd.h
>>>> @@ -151,7 +151,7 @@
>>>> "load ${devtype} ${devnum}:${distro_bootpart} " \
>>>> "${fdt_addr_r} ${prefix}${efi_fdtfile}\0" \
>>>> \
>>>> - "efi_dtb_prefixes=/ /dtb/ /dtb/current/\0" \
>>>> + "efi_dtb_prefixes=/ /dtb/ /dtb/current/ /dtbs/ /dtbs/current/\0" \
>>>> "scan_dev_for_efi=" \
>>>> "setenv efi_fdtfile ${fdtfile}; " \
>>>> BOOTENV_EFI_SET_FDTFILE_FALLBACK \
>>>> --
>>>> 2.33.0
>>>>
>>>>
>>
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2021-09-17 14:29 UTC | newest]
Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-09-17 11:02 [PATCH] distro_bootcmd: change the default dtb search path to include default kernel dtbs directory Qu Wenruo
2021-09-17 11:34 ` Mark Kettenis
2021-09-17 11:42 ` Qu Wenruo
2021-09-17 14:25 ` Mark Kettenis
2021-09-17 14:29 ` Qu Wenruo
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