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From: oliver <oohall@gmail.com>
Date: Thu, 23 Jun 2016 18:21:23 +1000
Message-ID: <CAOSf1CGEncYNgqi4gj0SK_v98mypcomgFgngbFjahSx3pnTccA@mail.gmail.com>
Subject: Re: [PATCHv4] powerpc/timer - large decrementer support
To: Denis Kirjanov <kirjanov@gmail.com>
Cc: linuxppc-dev@lists.ozlabs.org, Michael Neuling <mikey@neuling.org>,
 Jack Miller <jack@codezen.org>
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On Thu, Jun 23, 2016 at 6:02 PM, Denis Kirjanov <kirjanov@gmail.com> wrote:
> On 6/23/16, Oliver O'Halloran <oohall@gmail.com> wrote:
>> +static void __init set_decrementer_max(void)
>> +{
>> +     struct device_node *cpu;
>> +     const __be32 *fp;
>> +     u64 bits = 32;
>> +
>> +     /* Prior to ISAv3 the decrementer is always 32 bit */
>> +     if (!cpu_has_feature(CPU_FTR_ARCH_300))
>> +             return;
>> +
>> +     cpu = of_find_node_by_type(NULL, "cpu");
>> +     if (cpu)
>> +             fp = of_get_property(cpu, "ibm,dec-bits", NULL);
>> +
>> +     if (cpu && fp) {
>> +             bits = of_read_number(fp, 1);
>> +
>> +             if (bits > 64 || bits < 32) {
>> +                     pr_warn("time_init: firmware supplied invalid ibm,dec-bits");
>> +                     bits = 32;
>> +             }
>> +
>> +
>> +             /* calculate the signed maximum given this many bits */
>> +             decrementer_max = (1ul << (bits - 1)) - 1;
>> +     }
>> +
>> +     pr_info("time_init: %llu bit decrementer (max: %llx)\n",
>> +             bits, decrementer_max);
>> +}
> the call to of_node_put(cpu) is missing in the function.

Well spotted, thanks.