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Message-ID: <bf97d10b-d5c9-46d6-c440-fc7de09c3abf@flygoat.com>
Date:   Tue, 7 Jun 2022 19:27:36 +0100
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Subject: Re: [PATCH v2 11/12] MIPS: Report cluster in /proc/cpuinfo
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To:     Marc Zyngier <maz@kernel.org>,
        Dragan Mladjenovic <Dragan.Mladjenovic@syrmia.com>
Cc:     Thomas Bogendoerfer <tsbogend@alpha.franken.de>,
        Chao-ying Fu <cfu@wavecomp.com>,
        Daniel Lezcano <daniel.lezcano@linaro.org>,
        Geert Uytterhoeven <geert@linux-m68k.org>,
        Greg Ungerer <gerg@kernel.org>,
        Hauke Mehrtens <hauke@hauke-m.de>,
        Ilya Lipnitskiy <ilya.lipnitskiy@gmail.com>,
        linux-kernel@vger.kernel.org, linux-mips@vger.kernel.org,
        Paul Burton <paulburton@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Serge Semin <fancer.lancer@gmail.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Tiezhu Yang <yangtiezhu@loongson.cn>
References: <20220525121030.16054-1-Dragan.Mladjenovic@syrmia.com>
 <20220525121030.16054-12-Dragan.Mladjenovic@syrmia.com>
 <87sfoi3pek.wl-maz@kernel.org>
From:   Jiaxun Yang <jiaxun.yang@flygoat.com>
In-Reply-To: <87sfoi3pek.wl-maz@kernel.org>
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在 2022/6/6 14:14, Marc Zyngier 写道:
> On Wed, 25 May 2022 13:10:29 +0100,
> Dragan Mladjenovic <Dragan.Mladjenovic@syrmia.com> wrote:
>> From: Paul Burton <paulburton@kernel.org>
>>
>> When >= CM3.5 output cluster number.
>>
>> Signed-off-by: Paul Burton <paulburton@kernel.org>
>> Signed-off-by: Dragan Mladjenovic <dragan.mladjenovic@syrmia.com>
>>
>> diff --git a/arch/mips/kernel/proc.c b/arch/mips/kernel/proc.c
>> index bb43bf850314..a66e7705315d 100644
>> --- a/arch/mips/kernel/proc.c
>> +++ b/arch/mips/kernel/proc.c
>> @@ -12,6 +12,7 @@
>>   #include <asm/cpu.h>
>>   #include <asm/cpu-features.h>
>>   #include <asm/idle.h>
>> +#include <asm/mips-cps.h>
>>   #include <asm/mipsregs.h>
>>   #include <asm/processor.h>
>>   #include <asm/prom.h>
>> @@ -282,6 +283,8 @@ static int show_cpuinfo(struct seq_file *m, void *v)
>>   	seq_printf(m, "kscratch registers\t: %d\n",
>>   		      hweight8(cpu_data[n].kscratch_mask));
>>   	seq_printf(m, "package\t\t\t: %d\n", cpu_data[n].package);
>> +	if (mips_cm_revision() >= CM_REV_CM3_5)
>> +		seq_printf(m, "cluster\t\t\t: %d\n", cpu_cluster(&cpu_data[n]));
>>   	seq_printf(m, "core\t\t\t: %d\n", cpu_core(&cpu_data[n]));
>>   
>>   #if defined(CONFIG_MIPS_MT_SMP) || defined(CONFIG_CPU_MIPSR6)
> This will break userspace. Please don't do that.
Hmm, userspace always parse cpuinfo line by line so I guess it won't be
a problem if we add a new line here.

We accumulated some new additions to cpuinfo in past years and there
was never a single complain for that.

Though I don't like the idea of using CM version to switch on the cluster
display....

Thanks
- Jiaxun

>
> 	M.
>