[PATCH V2] spi: Update speed/mode on change

Thu Apr 1 00:50:48 CEST 2021

Hi Marek,

On Thu, 1 Apr 2021 at 11:39, Marek Vasut <marex at denx.de> wrote:
>
> On 3/31/21 11:45 PM, Tom Rini wrote:
> > On Wed, Mar 31, 2021 at 10:05:28PM +0200, Marek Vasut wrote:
> >> On 3/31/21 9:40 PM, Tom Rini wrote:
> >>> On Wed, Mar 31, 2021 at 03:26:27PM -0400, Tom Rini wrote:
> >>>> On Wed, Mar 31, 2021 at 09:18:28PM +0200, Marek Vasut wrote:
> >>>>> On 3/29/21 4:40 AM, Marek Vasut wrote:
> >>>>>> On 3/29/21 4:09 AM, Marek Vasut wrote:
> >>>>>>> On 3/29/21 3:59 AM, Tom Rini wrote:
> >>>>>>>> On Mon, Mar 29, 2021 at 03:32:51AM +0200, Marek Vasut wrote:
> >>>>>>>>> On 3/28/21 11:30 PM, Tom Rini wrote:
> >>>>>>>>>> On Fri, Feb 26, 2021 at 03:21:24PM +0100, Marek Vasut wrote:
> >>>>>>>>>>
> >>>>>>>>>>> The spi_get_bus_and_cs() may be called on the same bus and chipselect
> >>>>>>>>>>> with different frequency or mode. This is valid usecase, but the code
> >>>>>>>>>>> fails to notify the controller of such a configuration change. Call
> >>>>>>>>>>> spi_set_speed_mode() in case bus frequency or bus mode changed to let
> >>>>>>>>>>> the controller update the configuration.
> >>>>>>>>>>>
> >>>>>>>>>>> The problem can easily be triggered using the sspi command:
> >>>>>>>>>>> => sspi 0:0 at 1000
> >>>>>>>>>>> => sspi 0:0 at 2000
> >>>>>>>>>>> Without this patch, both transfers happen at 1000
> >>>>>>>>>>> Hz. With this patch,
> >>>>>>>>>>> the later transfer happens correctly at 2000 Hz.
> >>>>>>>>>>>
> >>>>>>>>>>> Signed-off-by: Marek Vasut <marex at denx.de>
> >>>>>>>>>>> Cc: Jagan Teki <jagan at amarulasolutions.com>
> >>>>>>>>>>> Cc: Patrick Delaunay <patrick.delaunay at st.com>
> >>>>>>>>>>
> >>>>>>>>>> So, very reliably I can make:
> >>>>>>>>>> https://source.denx.de/u-boot/u-boot/-/jobs/245517
> >>>>>>>>>> happen locally as well building with clang.  It's not
> >>>>>>>>>> obvious to me why
> >>>>>>>>>> the test now fails however.
> >>>>>>>>>
> >>>>>>>>> Can you please be more specific / clear ? I have no idea what those 300
> >>>>>>>>> lines of cryptic output mean, nor what are you trying to say
> >>>>>>>>> by the above,
> >>>>>>>>> sorry.
> >>>>>>>>
> >>>>>>>> If you build with clang, for sandbox, and run the tests, U-Boot crashes
> >>>>>>>> in the unit tests that you start with "ut dm".
> >>>>>>>
> >>>>>>> And that is related to this patch somehow ? How ?
> >>>>>>
> >>>>>> ... after further discussion off-list to get a better test case
> >>>>>> description ...
> >>>>>>
> >>>>>> It seems the problem is in sound_beep() and it is unrelated to this
> >>>>>> patch, as the same problem happens with / without this patch being
> >>>>>> applied, on:
> >>>>>>
> >>>>>> a7d3ac61482 ("Merge branch '2021-03-28-assorted-bugfixes'")
> >>>>>>
> >>>>>> $ clang --version
> >>>>>> Debian clang version 11.0.1-2
> >>>>>> ...
> >>>>>> $ make CC=clang HOSTCC=clang sandbox_defconfig
> >>>>>> $ make CC=clang HOSTCC=clang
> >>>>>> $ gdb --args ./u-boot -d arch/sandbox/dts/test.dtb
> >>>>>> => ut dm
> >>>>>> ...
> >>>>>> Program received signal SIGSEGV, Segmentation fault.
> >>>>>> dlfree (mem=<optimized out>, mem at entry=0x15c19c50) at
> >>>>>> common/dlmalloc.c:1623
> >>>>>> 1623      if (!(inuse_bit_at_offset(next, nextsz)))   /* consolidate
> >>>>>> forward */
> >>>>>> (gdb) bt
> >>>>>> #0  dlfree (mem=<optimized out>, mem at entry=0x15c19c50) at
> >>>>>> common/dlmalloc.c:1623
> >>>>>> #1  0x00000000004759e3 in sound_beep (dev=0x15c05580, msecs=<optimized
> >>>>>> out>, frequency_hz=100)
> >>>>>>       at drivers/sound/sound-uclass.c:118
> >>>>>
> >>>>> Tom, any further comments ? It seems your claim that this bugfix is causing
> >>>>> problems with clang is not correct, so I think it should still be applied to
> >>>>> v2021.04 , unless you can provide more details about the clang problem ?
> >>>>
> >>>> There's at least a few funny things going on.  Yes, apparently outside
> >>>> of CI building sandbox with clang and running the tests manually crashes
> >>>> in sound, before it gets to the SPI tests.  Except when it crashes on
> >>>> the SPI tests instead, which I did get to happen once.  So there's some
> >>>> sort of use-after-free or similar bug around here somewhere, similar to
> >>>> how we can't use the -fstack-protector patch as it exposes other real
> >>>> problems that need to be fixed first.
> >>>>
> >>>> So, I'll see if with a new tag and a few other changes having been made
> >>>> we once again get to the point where your patch doesn't trigger this
> >>>> issue.  But since it's also not a regression fix, if no one can figure
> >>>> out what to do about fixing what clang shows us, then it can wait for
> >>>> v2021.07.
> >>>
> >>> Nope, still gets things to blow up:
> >>> https://source.denx.de/u-boot/u-boot/-/jobs/246848
> >>>
> >>> and yes, it would be nice if when the reason a pytest fails is that
> >>> U-Boot crashed, it would say something more clear than "OSError: [Errno
> >>> 5] Input/output error" and you have to know that means U-Boot died.
> >>
> >> Can you please provide a detailed test case how to reproduce this ?
> >> So far I don't have one, the only test description I got is "install random
> >> version of clang, run ut dm and it fails", but that kind of imprecise test
> >> description is really not useful. Please provide more specific instructions.
> >
> > Yes, follow what CI does.  It's done in a container, so you can have the
> > exact same runtime and the tests are in .azure-pipelines.yml and
> > .gitlab-ci.yml or if you look at
> > https://source.denx.de/u-boot/u-boot/-/jobs/246848/raw you can see the
> > commands in there.
>
> Can you please provide me the exact commands to run to reproduce this
> problem ? I just spent a lot of time trying to find this one single
> command in a wall of text, "ut dm spi_find", which I think is the one
> failing for you ? It seems to work for me with and without the patch:
>
> $ ./u-boot -d arch/sandbox/dts/test.dtb
> sandbox: starting...
>
>
> U-Boot 2021.04-rc5-00005-g583b6858733 (Apr 01 2021 - 00:34:09 +0200)
>
> Model: sandbox
> DRAM:  128 MiB
> WDT:   Started with servicing (60s timeout)
> MMC:   mmc2: 2 (SD), mmc1: 1 (SD), mmc0: 0 (SD)
> In:    serial
> Out:   vidconsole
> Err:   vidconsole
> Model: sandbox
> SCSI:
> Net:   eth0: eth at 10002000, eth5: eth at 10003000, eth3: sbe5, eth6:
> eth at 10004000
> Hit any key to stop autoboot:  0
>
> Without patch
> => ut dm spi_find
> Test: dm_test_spi_find: spi.c
> test/dm/spi.c:71, dm_test_spi_find(): 0 == spi_get_bus_and_cs(busnum,
> cs, speed, mode, "jedec_spi_nor", "name", &bus, &slave): Expected 0x0
> (0), got 0xfffffffb (-5)
> Test: dm_test_spi_find: spi.c (flat tree)
> test/dm/spi.c:71, dm_test_spi_find(): 0 == spi_get_bus_and_cs(busnum,
> cs, speed, mode, "jedec_spi_nor", "name", &bus, &slave): Expected 0x0
> (0), got 0xfffffffb (-5)
> Failures: 2
>
> With patch
> => ut dm spi_find
> Test: dm_test_spi_find: spi.c
> test/dm/spi.c:71, dm_test_spi_find(): 0 == spi_get_bus_and_cs(busnum,
> cs, speed, mode, "jedec_spi_nor", "name", &bus, &slave): Expected 0x0
> (0), got 0xfffffffb (-5)
> Test: dm_test_spi_find: spi.c (flat tree)
> test/dm/spi.c:71, dm_test_spi_find(): 0 == spi_get_bus_and_cs(busnum,
> cs, speed, mode, "jedec_spi_nor", "name", &bus, &slave): Expected 0x0
> (0), got 0xfffffffb (-5)
> Failures: 2

The Python test sets up a SPI-flash file (spi.bin) that is needed by the test.

I use this alias:

# Run a pytest on sandbox
# $1: Name of test to run (optional, else run all)
function pyt {
   test/py/test.py -B sandbox --build-dir /tmp/b/sandbox ${1:+"-k $1"}
}

then 'pyt spi_find'

Once you've done that once you can do what you had before:

./u-boot -T

Regards,
Simon