On Mon, Jan 19, 2015 at 8:13 PM, Joshua Kinard <kumba@xxxxxxxxxx> wrote:
> On 01/19/2015 21:43, Matt Turner wrote:
>> On Mon, Jan 19, 2015 at 4:56 PM, Joshua Kinard <kumba@xxxxxxxxxx> wrote:
>>> On 01/19/2015 14:34, Matt Turner wrote:
>>>> On Sun, Jan 18, 2015 at 5:30 PM, Joshua Kinard <kumba@xxxxxxxxxx> wrote:
>>>>> diff --git a/arch/mips/kernel/cpu-probe.c b/arch/mips/kernel/cpu-probe.c
>>>>> index 5342674..3f334a8 100644
>>>>> --- a/arch/mips/kernel/cpu-probe.c
>>>>> +++ b/arch/mips/kernel/cpu-probe.c
>>>>> @@ -833,8 +833,13 @@ static inline void cpu_probe_legacy(struct cpuinfo_mips *c, unsigned int cpu)
>>>>> c->tlbsize = 64;
>>>>> break;
>>>>> case PRID_IMP_R14000:
>>>>> - c->cputype = CPU_R14000;
>>>>> - __cpu_name[cpu] = "R14000";
>>>>> + if (((c->processor_id >> 4) & 0x0f) > 2) {
>>>>> + c->cputype = CPU_R16000;
>>>>> + __cpu_name[cpu] = "R16000";
>>>>> + } else {
>>>>> + c->cputype = CPU_R14000;
>>>>> + __cpu_name[cpu] = "R14000";
>>>>> + }
>>>>
>>>> It looks like this is the only hunk that has a functional change, and
>>>> that is simply setting __cpu_name[cpu] to "R16000"
>>>>
>>>> You can do that without adding CPU_R16000 to the enumeration. I don't
>>>> see that adding it accomplishes anything.
>>>>
>>>
>>> It mirrors what CPU_R14000 and CPU_R12000 do. I won't rule out that, down the
>>> road, something about the R16K might be different enough from the R14K to
>>> require one of these other spots later on, so adding it now isn't going to
>>> adversely affect things.
>>
>> That's justification for removing CPU_R14000 as well, not adding CPU_R16000.
>>
>> Otherwise it's just adding useless code.
>
> R14000 has a different CPU PRId than R12000 or R10000, so the code that sets
> the icache/scache linesz wouldn't know to apply to R14K, including the writing
> the the FrameMask register in CP0. Octane and Origin2K/Onyx2 can both use
> R14000 CPUs, so this is a bad suggestion, as removing R14000 detection would
> render those systems inoperable with those CPUs. I know, cause I'm the one
> that actually sent the R14K patch in 9 years ago w/ commit 44d921b2 .
Sorry, you're not getting it.
git grep -B1 CPU_R14000
Notice how all of the instances of CPU_R14000 are preceded by
CPU_R12000? That's because CPU_R14000 doesn't do anything differently.
All you should do to remove CPU_R14000 is to set c->cputype =
CPU_R12000 in the PRID_IMP_R14000 case in cpu-probe.c.
