Re: [PATCH v5 10/11] hw/arm: Wire up BMC boot flash for npcm750-evb and quanta-gsj - Philippe Mathieu-Daudé

From: "Philippe Mathieu-Daudé" <f4bug@amsat.org>
To: Thomas Huth <thuth@redhat.com>,
	Havard Skinnemoen <hskinnemoen@google.com>,
	Markus Armbruster <armbru@redhat.com>
Cc: "Kevin Wolf" <kwolf@redhat.com>,
	"Peter Maydell" <peter.maydell@linaro.org>,
	Qemu-block <qemu-block@nongnu.org>,
	"QEMU Developers" <qemu-devel@nongnu.org>,
	"CS20 KFTing" <kfting@nuvoton.com>,
	qemu-arm <qemu-arm@nongnu.org>, "Cédric Le Goater" <clg@kaod.org>,
	"IS20 Avi Fishman" <Avi.Fishman@nuvoton.com>
Subject: Re: [PATCH v5 10/11] hw/arm: Wire up BMC boot flash for npcm750-evb and quanta-gsj
Date: Fri, 17 Jul 2020 10:27:15 +0200	[thread overview]
Message-ID: <d66bf4fe-7349-a90f-c4fb-a80de7597819@amsat.org> (raw)
In-Reply-To: <416d5243-dc8e-37c6-197f-96dec1c9f5cc@redhat.com>

On 7/17/20 10:03 AM, Thomas Huth wrote:
> On 17/07/2020 09.48, Philippe Mathieu-Daudé wrote:
>> +Thomas
> 
>> On 7/16/20 10:56 PM, Havard Skinnemoen wrote:
>>> On Wed, Jul 15, 2020 at 1:54 PM Havard Skinnemoen
>>> <hskinnemoen@google.com> wrote:
>>>>
>>>> On Wed, Jul 15, 2020 at 3:57 AM Philippe Mathieu-Daudé <f4bug@amsat.org> wrote:
>>>>>
>>>>> On 7/15/20 11:00 AM, Markus Armbruster wrote:
>>>>>> Now my point.  Why first make up user configuration, then use that to
>>>>>> create a BlockBackend, when you could just go ahead and create the
>>>>>> BlockBackend?
>>>>>
>>>>> CLI issue mostly.
>>>>>
>>>>> We can solve it similarly to the recent "sdcard: Do not allow invalid SD
>>>>> card sizes" patch:
>>>>>
>>>>>  if (!dinfo) {
>>>>>      error_setg(errp, "Missing SPI flash drive");
>>>>>      error_append_hint(errp, "You can use a dummy drive using:\n");
>>>>>      error_append_hint(errp, "-drive if=mtd,driver=null-co,"
>>>>>                              "read-ones=on,size=64M\n);
>>>>>      return;
>>>>>  }
>>>>>
>>>>> having npcm7xx_connect_flash() taking an Error* argument,
>>>>> and MachineClass::init() call it with &error_fatal.
>>>>
>>>> Erroring out if the user specifies a configuration that can't possibly
>>>> boot sounds good to me. Better than trying to come up with defaults
>>>> that are still not going to result in a bootable system.
>>>>
>>>> For testing recovery paths, I think it makes sense to explicitly
>>>> specify a null device as you suggest.
>>>
>>> Hmm, one problem. qom-test fails with
>>>
>>> qemu-system-aarch64: Missing SPI flash drive
>>> You can add a dummy drive using:
>>> -drive if=mtd,driver=null-co,read-zeroes=on,size=32M
>>> Broken pipe
>>> /usr/local/google/home/hskinnemoen/qemu/for-upstream/tests/qtest/libqtest.c:166:
>>> kill_qemu() tried to terminate QEMU process but encountered exit
>>> status 1 (expected 0)
>>> ERROR qom-test - too few tests run (expected 68, got 7)
>>>
>>> So it looks like we might need a different solution to this, unless we
>>> want to make generic tests more machine-aware...
> 
> I didn't follow the other mails in this thread, but what we usually do
> in such a case: Add a "if (qtest_enabled())" check to the device or the
> machine to ignore the error if it is running in qtest mode.

Hmm I'm not sure it works in this case. We could do:

  if (!dinfo) {
     if (qtest) {
        /* create null drive for qtest */
        opts = ...;
        dinfo = drive_new(opts, IF_MTD, &error_abort);
     } else {
        /* teach user to use proper CLI */
        error_setg(errp, "Missing SPI flash drive");
        error_append_hint(errp, "You can use a dummy drive using:\n");
        error_append_hint(errp, "-drive if=mtd,driver=null-co,"
                                "read-ones=on,size=64M\n);
     }
  }

But I'm not sure Markus will enjoy it :)

Markus, any better idea about how to handle that with automatic qtests?

Thanks :)

Phil.

> 
>  Thomas
> 
> 