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* [U-Boot] [PATCH] x86: tsc: add support for reading CPU freq from cpuid
@ 2018-05-14  9:32 Christian Gmeiner
  2018-05-21 15:36 ` Christian Gmeiner
  2018-05-23  9:48 ` Bin Meng
  0 siblings, 2 replies; 5+ messages in thread
From: Christian Gmeiner @ 2018-05-14  9:32 UTC (permalink / raw)
  To: u-boot

Starting with cpuid level 0x16 (Skylake-based processors)
it is possible to get CPU base freq via cpuid.

This fixes booting on a skylake based system.

Signed-off-by: Christian Gmeiner <christian.gmeiner@gmail.com>
---
 drivers/timer/tsc_timer.c | 31 +++++++++++++++++++++++++------
 1 file changed, 25 insertions(+), 6 deletions(-)

diff --git a/drivers/timer/tsc_timer.c b/drivers/timer/tsc_timer.c
index c7fefd2031..96a3e55513 100644
--- a/drivers/timer/tsc_timer.c
+++ b/drivers/timer/tsc_timer.c
@@ -21,6 +21,17 @@
 
 DECLARE_GLOBAL_DATA_PTR;
 
+static unsigned long cpu_mhz_from_cpuid(void)
+{
+	if (gd->arch.x86_vendor != X86_VENDOR_INTEL)
+		return 0;
+
+	if (cpuid_eax(0) < 0x16)
+		return 0;
+
+	return cpuid_eax(0x16);
+}
+
 /*
  * According to Intel 64 and IA-32 System Programming Guide,
  * if MSR_PERF_STAT[31] is set, the maximum resolved bus ratio can be
@@ -343,14 +354,22 @@ static void tsc_timer_ensure_setup(void)
 	if (!gd->arch.clock_rate) {
 		unsigned long fast_calibrate;
 
+		fast_calibrate = cpu_mhz_from_cpuid();
+		if (fast_calibrate)
+			goto done;
+
 		fast_calibrate = cpu_mhz_from_msr();
-		if (!fast_calibrate) {
-			fast_calibrate = quick_pit_calibrate();
-			if (!fast_calibrate)
-				panic("TSC frequency is ZERO");
-		}
+		if (fast_calibrate)
+			goto done;
+
+		fast_calibrate = quick_pit_calibrate();
+		if (fast_calibrate)
+			goto done;
+
+		panic("TSC frequency is ZERO");
 
-		gd->arch.clock_rate = fast_calibrate * 1000000;
+		done:
+			gd->arch.clock_rate = fast_calibrate * 1000000;
 	}
 }
 
-- 
2.17.0

^ permalink raw reply related	[flat|nested] 5+ messages in thread

* [U-Boot] [PATCH] x86: tsc: add support for reading CPU freq from cpuid
  2018-05-14  9:32 [U-Boot] [PATCH] x86: tsc: add support for reading CPU freq from cpuid Christian Gmeiner
@ 2018-05-21 15:36 ` Christian Gmeiner
  2018-05-23  9:48 ` Bin Meng
  1 sibling, 0 replies; 5+ messages in thread
From: Christian Gmeiner @ 2018-05-21 15:36 UTC (permalink / raw)
  To: u-boot

ping

Am Mo., 14. Mai 2018 um 11:32 Uhr schrieb Christian Gmeiner <
christian.gmeiner@gmail.com>:

> Starting with cpuid level 0x16 (Skylake-based processors)
> it is possible to get CPU base freq via cpuid.

> This fixes booting on a skylake based system.

> Signed-off-by: Christian Gmeiner <christian.gmeiner@gmail.com>
> ---
>   drivers/timer/tsc_timer.c | 31 +++++++++++++++++++++++++------
>   1 file changed, 25 insertions(+), 6 deletions(-)

> diff --git a/drivers/timer/tsc_timer.c b/drivers/timer/tsc_timer.c
> index c7fefd2031..96a3e55513 100644
> --- a/drivers/timer/tsc_timer.c
> +++ b/drivers/timer/tsc_timer.c
> @@ -21,6 +21,17 @@

>   DECLARE_GLOBAL_DATA_PTR;

> +static unsigned long cpu_mhz_from_cpuid(void)
> +{
> +       if (gd->arch.x86_vendor != X86_VENDOR_INTEL)
> +               return 0;
> +
> +       if (cpuid_eax(0) < 0x16)
> +               return 0;
> +
> +       return cpuid_eax(0x16);
> +}
> +
>   /*
>    * According to Intel 64 and IA-32 System Programming Guide,
>    * if MSR_PERF_STAT[31] is set, the maximum resolved bus ratio can be
> @@ -343,14 +354,22 @@ static void tsc_timer_ensure_setup(void)
>          if (!gd->arch.clock_rate) {
>                  unsigned long fast_calibrate;

> +               fast_calibrate = cpu_mhz_from_cpuid();
> +               if (fast_calibrate)
> +                       goto done;
> +
>                  fast_calibrate = cpu_mhz_from_msr();
> -               if (!fast_calibrate) {
> -                       fast_calibrate = quick_pit_calibrate();
> -                       if (!fast_calibrate)
> -                               panic("TSC frequency is ZERO");
> -               }
> +               if (fast_calibrate)
> +                       goto done;
> +
> +               fast_calibrate = quick_pit_calibrate();
> +               if (fast_calibrate)
> +                       goto done;
> +
> +               panic("TSC frequency is ZERO");

> -               gd->arch.clock_rate = fast_calibrate * 1000000;
> +               done:
> +                       gd->arch.clock_rate = fast_calibrate * 1000000;
>          }
>   }

> --
> 2.17.0



-- 
greets
--
Christian Gmeiner, MSc

https://christian-gmeiner.info

^ permalink raw reply	[flat|nested] 5+ messages in thread

* [U-Boot] [PATCH] x86: tsc: add support for reading CPU freq from cpuid
  2018-05-14  9:32 [U-Boot] [PATCH] x86: tsc: add support for reading CPU freq from cpuid Christian Gmeiner
  2018-05-21 15:36 ` Christian Gmeiner
@ 2018-05-23  9:48 ` Bin Meng
  2018-05-23 12:01   ` Christian Gmeiner
  2018-05-25  3:57   ` Bin Meng
  1 sibling, 2 replies; 5+ messages in thread
From: Bin Meng @ 2018-05-23  9:48 UTC (permalink / raw)
  To: u-boot

On Mon, May 14, 2018 at 5:32 PM, Christian Gmeiner
<christian.gmeiner@gmail.com> wrote:
> Starting with cpuid level 0x16 (Skylake-based processors)
> it is possible to get CPU base freq via cpuid.
>
> This fixes booting on a skylake based system.
>
> Signed-off-by: Christian Gmeiner <christian.gmeiner@gmail.com>
> ---
>  drivers/timer/tsc_timer.c | 31 +++++++++++++++++++++++++------
>  1 file changed, 25 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/timer/tsc_timer.c b/drivers/timer/tsc_timer.c
> index c7fefd2031..96a3e55513 100644
> --- a/drivers/timer/tsc_timer.c
> +++ b/drivers/timer/tsc_timer.c
> @@ -21,6 +21,17 @@
>
>  DECLARE_GLOBAL_DATA_PTR;
>
> +static unsigned long cpu_mhz_from_cpuid(void)
> +{
> +       if (gd->arch.x86_vendor != X86_VENDOR_INTEL)
> +               return 0;
> +
> +       if (cpuid_eax(0) < 0x16)
> +               return 0;
> +
> +       return cpuid_eax(0x16);
> +}
> +
>  /*
>   * According to Intel 64 and IA-32 System Programming Guide,
>   * if MSR_PERF_STAT[31] is set, the maximum resolved bus ratio can be
> @@ -343,14 +354,22 @@ static void tsc_timer_ensure_setup(void)
>         if (!gd->arch.clock_rate) {
>                 unsigned long fast_calibrate;
>
> +               fast_calibrate = cpu_mhz_from_cpuid();
> +               if (fast_calibrate)
> +                       goto done;
> +
>                 fast_calibrate = cpu_mhz_from_msr();
> -               if (!fast_calibrate) {
> -                       fast_calibrate = quick_pit_calibrate();
> -                       if (!fast_calibrate)
> -                               panic("TSC frequency is ZERO");
> -               }
> +               if (fast_calibrate)
> +                       goto done;
> +
> +               fast_calibrate = quick_pit_calibrate();
> +               if (fast_calibrate)
> +                       goto done;
> +
> +               panic("TSC frequency is ZERO");
>
> -               gd->arch.clock_rate = fast_calibrate * 1000000;
> +               done:

nits: this indention is wrong, and will cause checkpatch warnings.

> +                       gd->arch.clock_rate = fast_calibrate * 1000000;
>         }
>  }

Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

I can fix the nits when applying.

Regards,
Bin

^ permalink raw reply	[flat|nested] 5+ messages in thread

* [U-Boot] [PATCH] x86: tsc: add support for reading CPU freq from cpuid
  2018-05-23  9:48 ` Bin Meng
@ 2018-05-23 12:01   ` Christian Gmeiner
  2018-05-25  3:57   ` Bin Meng
  1 sibling, 0 replies; 5+ messages in thread
From: Christian Gmeiner @ 2018-05-23 12:01 UTC (permalink / raw)
  To: u-boot

Am Mi., 23. Mai 2018 um 11:48 Uhr schrieb Bin Meng <bmeng.cn@gmail.com>:

> On Mon, May 14, 2018 at 5:32 PM, Christian Gmeiner
> <christian.gmeiner@gmail.com> wrote:
> > Starting with cpuid level 0x16 (Skylake-based processors)
> > it is possible to get CPU base freq via cpuid.
> >
> > This fixes booting on a skylake based system.
> >
> > Signed-off-by: Christian Gmeiner <christian.gmeiner@gmail.com>
> > ---
> >  drivers/timer/tsc_timer.c | 31 +++++++++++++++++++++++++------
> >  1 file changed, 25 insertions(+), 6 deletions(-)
> >
> > diff --git a/drivers/timer/tsc_timer.c b/drivers/timer/tsc_timer.c
> > index c7fefd2031..96a3e55513 100644
> > --- a/drivers/timer/tsc_timer.c
> > +++ b/drivers/timer/tsc_timer.c
> > @@ -21,6 +21,17 @@
> >
> >  DECLARE_GLOBAL_DATA_PTR;
> >
> > +static unsigned long cpu_mhz_from_cpuid(void)
> > +{
> > +       if (gd->arch.x86_vendor != X86_VENDOR_INTEL)
> > +               return 0;
> > +
> > +       if (cpuid_eax(0) < 0x16)
> > +               return 0;
> > +
> > +       return cpuid_eax(0x16);
> > +}
> > +
> >  /*
> >   * According to Intel 64 and IA-32 System Programming Guide,
> >   * if MSR_PERF_STAT[31] is set, the maximum resolved bus ratio can be
> > @@ -343,14 +354,22 @@ static void tsc_timer_ensure_setup(void)
> >         if (!gd->arch.clock_rate) {
> >                 unsigned long fast_calibrate;
> >
> > +               fast_calibrate = cpu_mhz_from_cpuid();
> > +               if (fast_calibrate)
> > +                       goto done;
> > +
> >                 fast_calibrate = cpu_mhz_from_msr();
> > -               if (!fast_calibrate) {
> > -                       fast_calibrate = quick_pit_calibrate();
> > -                       if (!fast_calibrate)
> > -                               panic("TSC frequency is ZERO");
> > -               }
> > +               if (fast_calibrate)
> > +                       goto done;
> > +
> > +               fast_calibrate = quick_pit_calibrate();
> > +               if (fast_calibrate)
> > +                       goto done;
> > +
> > +               panic("TSC frequency is ZERO");
> >
> > -               gd->arch.clock_rate = fast_calibrate * 1000000;
> > +               done:

> nits: this indention is wrong, and will cause checkpatch warnings.

Oops.

> > +                       gd->arch.clock_rate = fast_calibrate * 1000000;
> >         }
> >  }

> Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

> I can fix the nits when applying.


That would be great - thanks!
-- 
greets
--
Christian Gmeiner, MSc

https://christian-gmeiner.info

^ permalink raw reply	[flat|nested] 5+ messages in thread

* [U-Boot] [PATCH] x86: tsc: add support for reading CPU freq from cpuid
  2018-05-23  9:48 ` Bin Meng
  2018-05-23 12:01   ` Christian Gmeiner
@ 2018-05-25  3:57   ` Bin Meng
  1 sibling, 0 replies; 5+ messages in thread
From: Bin Meng @ 2018-05-25  3:57 UTC (permalink / raw)
  To: u-boot

On Wed, May 23, 2018 at 5:48 PM, Bin Meng <bmeng.cn@gmail.com> wrote:
> On Mon, May 14, 2018 at 5:32 PM, Christian Gmeiner
> <christian.gmeiner@gmail.com> wrote:
>> Starting with cpuid level 0x16 (Skylake-based processors)
>> it is possible to get CPU base freq via cpuid.
>>
>> This fixes booting on a skylake based system.
>>
>> Signed-off-by: Christian Gmeiner <christian.gmeiner@gmail.com>
>> ---
>>  drivers/timer/tsc_timer.c | 31 +++++++++++++++++++++++++------
>>  1 file changed, 25 insertions(+), 6 deletions(-)
>>
>> diff --git a/drivers/timer/tsc_timer.c b/drivers/timer/tsc_timer.c
>> index c7fefd2031..96a3e55513 100644
>> --- a/drivers/timer/tsc_timer.c
>> +++ b/drivers/timer/tsc_timer.c
>> @@ -21,6 +21,17 @@
>>
>>  DECLARE_GLOBAL_DATA_PTR;
>>
>> +static unsigned long cpu_mhz_from_cpuid(void)
>> +{
>> +       if (gd->arch.x86_vendor != X86_VENDOR_INTEL)
>> +               return 0;
>> +
>> +       if (cpuid_eax(0) < 0x16)
>> +               return 0;
>> +
>> +       return cpuid_eax(0x16);
>> +}
>> +
>>  /*
>>   * According to Intel 64 and IA-32 System Programming Guide,
>>   * if MSR_PERF_STAT[31] is set, the maximum resolved bus ratio can be
>> @@ -343,14 +354,22 @@ static void tsc_timer_ensure_setup(void)
>>         if (!gd->arch.clock_rate) {
>>                 unsigned long fast_calibrate;
>>
>> +               fast_calibrate = cpu_mhz_from_cpuid();
>> +               if (fast_calibrate)
>> +                       goto done;
>> +
>>                 fast_calibrate = cpu_mhz_from_msr();
>> -               if (!fast_calibrate) {
>> -                       fast_calibrate = quick_pit_calibrate();
>> -                       if (!fast_calibrate)
>> -                               panic("TSC frequency is ZERO");
>> -               }
>> +               if (fast_calibrate)
>> +                       goto done;
>> +
>> +               fast_calibrate = quick_pit_calibrate();
>> +               if (fast_calibrate)
>> +                       goto done;
>> +
>> +               panic("TSC frequency is ZERO");
>>
>> -               gd->arch.clock_rate = fast_calibrate * 1000000;
>> +               done:
>
> nits: this indention is wrong, and will cause checkpatch warnings.
>
>> +                       gd->arch.clock_rate = fast_calibrate * 1000000;
>>         }
>>  }
>
> Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
>
> I can fix the nits when applying.

Fixed the nits and
applied to u-boot-x86, thanks!

^ permalink raw reply	[flat|nested] 5+ messages in thread

end of thread, other threads:[~2018-05-25  3:57 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2018-05-14  9:32 [U-Boot] [PATCH] x86: tsc: add support for reading CPU freq from cpuid Christian Gmeiner
2018-05-21 15:36 ` Christian Gmeiner
2018-05-23  9:48 ` Bin Meng
2018-05-23 12:01   ` Christian Gmeiner
2018-05-25  3:57   ` Bin Meng

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