linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Fu Wei <fu.wei@linaro.org>
To: Mark Rutland <mark.rutland@arm.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>,
	Len Brown <lenb@kernel.org>,
	Daniel Lezcano <daniel.lezcano@linaro.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	Marc Zyngier <marc.zyngier@arm.com>,
	Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>,
	Sudeep Holla <sudeep.holla@arm.com>,
	Hanjun Guo <hanjun.guo@linaro.org>,
	linux-arm-kernel@lists.infradead.org,
	Linaro ACPI Mailman List <linaro-acpi@lists.linaro.org>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	ACPI Devel Maling List <linux-acpi@vger.kernel.org>,
	rruigrok@codeaurora.org, "Abdulhamid,
	Harb" <harba@codeaurora.org>,
	Christopher Covington <cov@codeaurora.org>,
	Timur Tabi <timur@codeaurora.org>,
	G Gregory <graeme.gregory@linaro.org>,
	Al Stone <al.stone@linaro.org>, Jon Masters <jcm@redhat.com>,
	Wei Huang <wei@redhat.com>, Arnd Bergmann <arnd@arndb.de>,
	Catalin Marinas <catalin.marinas@arm.com>,
	Will Deacon <will.deacon@arm.com>,
	Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>,
	Leo Duran <leo.duran@amd.com>, Wim Van Sebroeck <wim@iguana.be>,
	Guenter Roeck <linux@roeck-us.net>,
	linux-watchdog@vger.kernel.org, Tomasz Nowicki <tn@semihalf.com>,
	Christoffer Dall <christoffer.dall@linaro.org>,
	Julien Grall <julien.grall@arm.com>
Subject: Re: [PATCH v19 05/15] clocksource/drivers/arm_arch_timer: rework PPI determination
Date: Wed, 18 Jan 2017 07:49:43 +0800	[thread overview]
Message-ID: <CADyBb7sP42WqpJ5xiD9Yujn3ZjDBH_3-Te5-xF_adVDTo5fQqw@mail.gmail.com> (raw)
In-Reply-To: <20170116172927.GI5908@leverpostej>

Hi Mark,

On 17 January 2017 at 01:29, Mark Rutland <mark.rutland@arm.com> wrote:
> On Wed, Dec 21, 2016 at 02:45:53PM +0800, fu.wei@linaro.org wrote:
> [...]
>
>> -     if (is_hyp_mode_available() || !arch_timer_ppi[ARCH_TIMER_VIRT_PPI]) {
>> -             bool has_ppi;
>> +     if (is_hyp_mode_available() && is_kernel_in_hyp_mode())
>> +             return ARCH_TIMER_HYP_PPI;
>>
>> -             if (is_kernel_in_hyp_mode()) {
>> -                     arch_timer_uses_ppi = ARCH_TIMER_HYP_PPI;
>> -                     has_ppi = !!arch_timer_ppi[ARCH_TIMER_HYP_PPI];
>> -             } else {
>> -                     arch_timer_uses_ppi = ARCH_TIMER_PHYS_SECURE_PPI;
>> -                     has_ppi = (!!arch_timer_ppi[ARCH_TIMER_PHYS_SECURE_PPI] ||
>> -                                !!arch_timer_ppi[ARCH_TIMER_PHYS_NONSECURE_PPI]);
>> -             }
>> +     if (arch_timer_ppi[ARCH_TIMER_VIRT_PPI])
>> +             return ARCH_TIMER_VIRT_PPI;
>>
>> -             if (!has_ppi) {
>> -                     pr_warn("No interrupt available, giving up\n");
>> -                     return -EINVAL;
>> -             }
>> -     }
>> +     if (IS_ENABLED(CONFIG_ARM64))
>> +             return ARCH_TIMER_PHYS_NONSECURE_PPI;
>> +
>> +     return ARCH_TIMER_PHYS_SECURE_PPI;
>
> For a 32-bit platform booted at hyp (with a virt PPI available), the new
> logic will select ARCH_TIMER_VIRT_PPI. I beleive that will break KVM.
>
> I think the logic should be:
>
>         if (is_kernel_in_hyp_mode())
>                 return ARCH_TIMER_HYP_PPI;
>
>         if (!is_hyp_mode_available() &&
>             arch_timer_ppi[ARCH_TIMER_VIRT_PPI])
>                 return ARCH_TIMER_VIRT_PPI;
>
>         if (IS_ENABLED(CONFIG_ARM64))
>                 return ARCH_TIMER_PHYS_NONSECURE_PPI;
>
>         return ARCH_TIMER_PHYS_SECURE_PPI;
>
> Please use that instead (keeping the comment you retained).

Great thanks for pointing it out, that is bug.
also got this bug report from Huawei engineer.

I have fixed it using your example code, thanks!


>
>> +static int __init arch_timer_init(void)
>> +{
>> +     int ret;
>>
>>       ret = arch_timer_register();
>>       if (ret)
>> @@ -904,6 +906,13 @@ static int __init arch_timer_of_init(struct device_node *np)
>>       if (IS_ENABLED(CONFIG_ARM) &&
>>           of_property_read_bool(np, "arm,cpu-registers-not-fw-configured"))
>>               arch_timer_uses_ppi = ARCH_TIMER_PHYS_SECURE_PPI;
>> +     else
>> +             arch_timer_uses_ppi = arch_timer_select_ppi();
>> +
>> +     if (!arch_timer_ppi[arch_timer_uses_ppi]) {
>> +             pr_err("No interrupt available, giving up\n");
>> +             return -EINVAL;
>> +     }
>>
>>       /* On some systems, the counter stops ticking when in suspend. */
>>       arch_counter_suspend_stop = of_property_read_bool(np,
>> @@ -1049,6 +1058,12 @@ static int __init arch_timer_acpi_init(struct acpi_table_header *table)
>>       /* Get the frequency from CNTFRQ */
>>       arch_timer_detect_rate(NULL, NULL);
>>
>> +     arch_timer_uses_ppi = arch_timer_select_ppi();
>> +     if (!arch_timer_ppi[arch_timer_uses_ppi]) {
>> +             pr_err("No interrupt available, giving up\n");
>> +             return -EINVAL;
>> +     }
>
> I see that we have to duplicate this so we can special-case the
> DT-specific behaviour, so that's fine by me.

Yes, that is the reason of the duplication :-)

>
> If you can fix the arch_timer_select_ppi() logic as above, this should
> be fine.

Done, thanks :-)

>
> Thanks,
> Mark.



-- 
Best regards,

Fu Wei
Software Engineer
Red Hat

  reply	other threads:[~2017-01-17 23:49 UTC|newest]

Thread overview: 31+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-12-21  6:45 [PATCH v19 00/15] acpi, clocksource: add GTDT driver and GTDT support in arm_arch_timer fu.wei
2016-12-21  6:45 ` [PATCH v19 01/15] clocksource/drivers/arm_arch_timer: Move enums and defines to header file fu.wei
2016-12-21  6:45 ` [PATCH v19 02/15] clocksource/drivers/arm_arch_timer: Add a new enum for spi type fu.wei
2016-12-21  6:45 ` [PATCH v19 03/15] clocksource/drivers/arm_arch_timer: Improve printk relevant code fu.wei
2016-12-21  6:45 ` [PATCH v19 04/15] clocksource/drivers/arm_arch_timer: rename some enums and defines fu.wei
2016-12-21  6:45 ` [PATCH v19 05/15] clocksource/drivers/arm_arch_timer: rework PPI determination fu.wei
2017-01-16 17:29   ` Mark Rutland
2017-01-17 23:49     ` Fu Wei [this message]
2016-12-21  6:45 ` [PATCH v19 06/15] clocksource/drivers/arm_arch_timer: Rework counter frequency detection fu.wei
2017-01-16 17:50   ` Mark Rutland
2017-01-18  4:27     ` Fu Wei
2016-12-21  6:45 ` [PATCH v19 07/15] clocksource/drivers/arm_arch_timer: Refactor arch_timer_needs_probing fu.wei
2016-12-21  6:45 ` [PATCH v19 08/15] clocksource/drivers/arm_arch_timer: move arch_timer_needs_of_probing into DT init call fu.wei
2016-12-21  6:45 ` [PATCH v19 09/15] clocksource/drivers/arm_arch_timer: Introduce some new structs to prepare for GTDT fu.wei
2016-12-21  6:45 ` [PATCH v19 10/15] clocksource/drivers/arm_arch_timer: Refactor the timer init code " fu.wei
2017-01-16 18:30   ` Mark Rutland
2017-01-17 10:30     ` Fu Wei
2017-01-17 10:39       ` Fu Wei
2017-01-17 12:18       ` Timur Tabi
2017-01-17 12:29         ` Mark Rutland
2017-01-17 13:22           ` Fu Wei
2016-12-21  6:45 ` [PATCH v19 11/15] acpi/arm64: Add GTDT table parse driver fu.wei
2016-12-21  6:46 ` [PATCH v19 12/15] clocksource/drivers/arm_arch_timer: Simplify ACPI support code fu.wei
2016-12-21  6:46 ` [PATCH v19 13/15] acpi/arm64: Add memory-mapped timer support in GTDT driver fu.wei
2016-12-21  6:46 ` [PATCH v19 14/15] clocksource/drivers/arm_arch_timer: Add GTDT support for memory-mapped timer fu.wei
2016-12-21  6:46 ` [PATCH v19 15/15] acpi/arm64: Add SBSA Generic Watchdog support in GTDT driver fu.wei
2017-01-16  6:26 ` [PATCH v19 00/15] acpi, clocksource: add GTDT driver and GTDT support in arm_arch_timer Fu Wei
2017-01-16 12:01   ` Mark Rutland
2017-01-16 12:04     ` Fu Wei
2017-01-16 17:00 ` Mark Rutland
2017-01-17  9:14   ` Fu Wei

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=CADyBb7sP42WqpJ5xiD9Yujn3ZjDBH_3-Te5-xF_adVDTo5fQqw@mail.gmail.com \
    --to=fu.wei@linaro.org \
    --cc=Suravee.Suthikulpanit@amd.com \
    --cc=al.stone@linaro.org \
    --cc=arnd@arndb.de \
    --cc=catalin.marinas@arm.com \
    --cc=christoffer.dall@linaro.org \
    --cc=cov@codeaurora.org \
    --cc=daniel.lezcano@linaro.org \
    --cc=graeme.gregory@linaro.org \
    --cc=hanjun.guo@linaro.org \
    --cc=harba@codeaurora.org \
    --cc=jcm@redhat.com \
    --cc=julien.grall@arm.com \
    --cc=lenb@kernel.org \
    --cc=leo.duran@amd.com \
    --cc=linaro-acpi@lists.linaro.org \
    --cc=linux-acpi@vger.kernel.org \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-watchdog@vger.kernel.org \
    --cc=linux@roeck-us.net \
    --cc=lorenzo.pieralisi@arm.com \
    --cc=marc.zyngier@arm.com \
    --cc=mark.rutland@arm.com \
    --cc=rjw@rjwysocki.net \
    --cc=rruigrok@codeaurora.org \
    --cc=sudeep.holla@arm.com \
    --cc=tglx@linutronix.de \
    --cc=timur@codeaurora.org \
    --cc=tn@semihalf.com \
    --cc=wei@redhat.com \
    --cc=will.deacon@arm.com \
    --cc=wim@iguana.be \
    --subject='Re: [PATCH v19 05/15] clocksource/drivers/arm_arch_timer: rework PPI determination' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).