[PATCH 2/2] bootstage: Do not sort records

Simon Glass sjg at chromium.org
Thu Aug 29 00:17:01 CEST 2024


Hi Jonas,

On Wed, 28 Aug 2024 at 13:01, Jonas Karlman <jonas at kwiboo.se> wrote:
>
> Hi Simon,
>
> On 2024-08-28 20:11, Simon Glass wrote:
> > Hi again Jonas,
> >
> > On Wed, 28 Aug 2024 at 11:06, Simon Glass <sjg at chromium.org> wrote:
> >>
> >> Hi Jonas,
> >>
> >> On Wed, 28 Aug 2024 at 10:15, Jonas Karlman <jonas at kwiboo.se> wrote:
> >>>
> >>> Hi Simon,
> >>>
> >>> On 2024-08-28 18:01, Simon Glass wrote:
> >>>> Hi Jonas,
> >>>>
> >>>> On Tue, 6 Aug 2024 at 15:50, Simon Glass <sjg at chromium.org> wrote:
> >>>>>
> >>>>> Hi Jonas,
> >>>>>
> >>>>> On Sat, 3 Aug 2024 at 06:42, Jonas Karlman <jonas at kwiboo.se> wrote:
> >>>>>>
> >>>>>> The timer counter on Rockchip SoCs may be reset in TF-A, this may cause
> >>>>>> the bootstage records to be printed out of order and with an incorrect
> >>>>>> elapsed time.
> >>>>>
> >>>>> Eek can we just fix TF-A? That seems like a bug.
> >>>
> >>> TF-A is vendor blob, so we have no control of it.
> >>
> >> Can we replace it, or is it one of the ones that has not been released?
> >>
> >> Can you file a bug with the vendor?
> >>
> >>>
> >>>>>
> >>>>>>
> >>>>>> Fix this by not sorting the bootstage records.
> >>>>>>
> >>>>>> Before on a Radxa ZERO 3W (RK3566) board:
> >>>>>>
> >>>>>>   => bootstage report
> >>>>>>   Timer summary in microseconds (12 records):
> >>>>>>          Mark    Elapsed  Stage
> >>>>>>             0          0  reset
> >>>>>>         7,436      7,436  board_init_f
> >>>>>>       164,826    157,390  SPL
> >>>>>>       375,392    210,566  end phase
> >>>>>>       423,909     48,517  board_init_r
> >>>>>>       472,973     49,064  eth_common_init
> >>>>>>       476,848      3,875  main_loop
> >>>>>>       477,003        155  cli_loop
> >>>>>>
> >>>>>>   Accumulated time:
> >>>>>>                    7,181  of_live
> >>>>>>                   14,739  dm_spl
> >>>>>>                   15,029  dm_r
> >>>>>>                  315,150  dm_f
> >>>>>>
> >>>>>> With this the records can be printed in chronological order when the
> >>>>>> counter is reset and SPL and board_init_r records show correct elapsed
> >>>>>> time.
> >>>>>>
> >>>>>>   => bootstage report
> >>>>>>   Timer summary in microseconds (12 records):
> >>>>>>          Mark    Elapsed  Stage
> >>>>>>             0          0  reset
> >>>>>>       164,437    164,437  SPL
> >>>>>>       375,023    210,586  end phase
> >>>>>>         7,437      7,437  board_init_f
> >>>>>>       424,390    416,953  board_init_r
> >>>>>>       473,515     49,125  eth_common_init
> >>>>>>       477,402      3,887  main_loop
> >>>>>>       477,571        169  cli_loop
> >>>>>>
> >>>>>>   Accumulated time:
> >>>>>>                   14,734  dm_spl
> >>>>>>                  315,646  dm_f
> >>>>>>                    7,339  of_live
> >>>>>>                   14,977  dm_r
> >>>>>>
> >>>>>> For the tested board external TPL and BROM take ~164 ms to initialize
> >>>>>> DRAM and load SPL, SPL take ~210ms to load images from FIT and U-Boot
> >>>>>> proper take ~477ms to reach cli prompt.
> >>>>>>
> >>>>>> Signed-off-by: Jonas Karlman <jonas at kwiboo.se>
> >>>>>> ---
> >>>>>>  common/bootstage.c | 12 ++----------
> >>>>>>  1 file changed, 2 insertions(+), 10 deletions(-)
> >>>>>>
> >>>>
> >>>> To put this more strongly, this breaks the timing output on other boards.
> >>>
> >>> Please elaborate, I cannot understand why not sorting would break output
> >>> on other boards, are other boards adding records out of order?
> >>>
> >>> Do you have an example of how this change break other boards?
> >>
> >> Oh sure. The original reason was that the array was ordered by ID.
> >> That was changed in [1], which I forgot about.
> >>
> >> The other bit is for coreboot (or potentially other prior phases) we
> >> receive timestamps as a block and add them into U-Boot. We want these
> >> to appear in the correct order with respect to the ones already adding
> >> to U-Boot.
> >>
> >> Sadly coreboot uses its own toolchain and I seem to have deleted it,
> >> but once it finishes building the world I will give it a try.
> >
> > OK I gave up and just built one toolchain instead of every one known
> > to man, which is the default.
> >
> > The code has seriously rotted and is a somewhat fascinating window
> > into what U-Boot was like 12 years ago...I will send a little series.
> >
> > Anyway, the start-romstage and device-xxx things below come from coreboot.
>
> Interesting, so coreboot is not running before U-Boot on this platform,
> is it running in parallel with U-Boot?

It runs before, but U-Boot picks up the timestamps once it is ready to
do so, i.e. after bootstage is inited.

>
> How is timestamp_add_to_bootstage() called in U-Boot, I cannot see any
> call to it, what am I missing?

Yes, it was deleted. I just sent a series to bring i tback.

>
> Guessing the records need to be sorted after/during that function call?
>
> Also look like the sorting is done in bootstage_report() so the report
> is possible logged to FDT with an unsorted order.

Yes, although that shouldn't really matter. Perhaps it is worth fixing?

>
> Let me know what you want me to do with this, I will drop this for now
> and just keep carry this patch in my local tree.

Hmmm step one is to complain about the bug. If it exists in ATF
upstream, then it should be fixed. I can have a crack at fixing it if
so. If it is a vendor binary, then they should fix it.

Step 2, I suggest a Kconfig option enabled for these boards, so it is
clear it is a workaround.

Regards,
Simon


> >
> > => bootstage repo
> > Timer summary in microseconds (20 records):
> >        Mark    Elapsed  Stage
> >           0          0  reset
> >      25,322     25,322  board_init_f
> >      32,175      6,853  start-romstage
> >     117,158     84,983  board_init_r
> >     208,409     91,251  device-initialize
> >     293,286     84,877  device-done
> >     547,606    254,320  selfboot-jump
> >     621,050     73,444  eth_common_init
> >     699,570     78,520  eth_initialize
> >     744,210     44,640  main_loop
> >     761,030     16,820  usb_start
> >   3,988,265  3,227,235  netboot_common
> >   3,988,330         65  eth_start
> >   6,316,294  2,327,964  bootp_start
> >  12,286,385  5,970,091  bootp_stop
> >  12,297,353     10,968  netboot_common
> >  12,300,596      3,243  netboot_common
> >  28,327,263 16,026,667  cli_loop
> >
> > Accumulated time:
> >                  8,600  dm_r
> >                  8,659  dm_f
> >
> > Without the sort, I see:
> >
> > Timer summary in microseconds (18 records):
> >        Mark    Elapsed  Stage
> >           0          0  reset
> >      36,582     36,582  board_init_f
> >     125,775     89,193  board_init_r
> >     642,577    516,802  eth_common_init
> >     721,321     78,744  eth_initialize
> >      31,357429,427,733,2  start-romstage
> >     247,602    216,245  device-initialize
> >     333,879     86,277  device-done
> >     596,043    262,164  selfboot-jump
> >     765,897    169,854  main_loop
> >     783,397     17,500  usb_start
> >   4,043,423  3,260,026  netboot_common
> >   4,043,489         66  eth_start
> >   6,371,702  2,328,213  bootp_start
> >  11,609,247  5,237,545  netboot_common
> >  15,476,116  3,866,869  cli_loop
> >
> > Accumulated time:
> >                  8,639  dm_f
> >                  8,923  dm_r
> >
> >>
> >>>
> >>>>
> >>>> At the very least, this should be Kconfig option just enabled for
> >>>> boards with a broken ATF.
> >>>
> >>> I can add a Kconfig option, but would like to understand why other/any
> >>> board would need to sort the records in the first place.
> >>
> >> OK.
> >
> > Regards,
> > Simon
> >
> >>
> >> [1] 03ecac31498 bootstage: Use rec_count as the array index
>


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