diff mbox series

[V3,17/20] RISC-V: time.c: Add ACPI support for time_init()

Message ID 20230303133647.845095-18-sunilvl@ventanamicro.com
State New
Headers
Series Add basic ACPI support for RISC-V |

Commit Message

Sunil V L March 3, 2023, 1:36 p.m. UTC 
  On ACPI based platforms, timer related information is
available in RHCT. Add ACPI based probe support to the
timer initialization.

Signed-off-by: Sunil V L <sunilvl@ventanamicro.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
---
 arch/riscv/kernel/time.c | 23 +++++++++++++++++------
 1 file changed, 17 insertions(+), 6 deletions(-)

Comments

Conor Dooley March 6, 2023, 9:09 p.m. UTC | #1 
On Fri, Mar 03, 2023 at 07:06:44PM +0530, Sunil V L wrote:
> On ACPI based platforms, timer related information is
> available in RHCT. Add ACPI based probe support to the
> timer initialization.
> 
> Signed-off-by: Sunil V L <sunilvl@ventanamicro.com>
> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
> ---
>  arch/riscv/kernel/time.c | 23 +++++++++++++++++------
>  1 file changed, 17 insertions(+), 6 deletions(-)
> 
> diff --git a/arch/riscv/kernel/time.c b/arch/riscv/kernel/time.c
> index babaf3b48ba8..2c29543549c3 100644
> --- a/arch/riscv/kernel/time.c
> +++ b/arch/riscv/kernel/time.c
> @@ -4,6 +4,7 @@
>   * Copyright (C) 2017 SiFive
>   */
>  
> +#include <linux/acpi.h>
>  #include <linux/of_clk.h>
>  #include <linux/clockchips.h>
>  #include <linux/clocksource.h>
> @@ -18,17 +19,27 @@ EXPORT_SYMBOL_GPL(riscv_timebase);
>  void __init time_init(void)
>  {
>  	struct device_node *cpu;
> +	struct acpi_table_rhct *rhct;
> +	acpi_status status;
>  	u32 prop;
>  
> -	cpu = of_find_node_by_path("/cpus");
> -	if (!cpu || of_property_read_u32(cpu, "timebase-frequency", &prop))
> -		panic(KERN_WARNING "RISC-V system with no 'timebase-frequency' in DTS\n");
> -	of_node_put(cpu);
> -	riscv_timebase = prop;
> +	if (acpi_disabled) {
> +		cpu = of_find_node_by_path("/cpus");
> +		if (!cpu || of_property_read_u32(cpu, "timebase-frequency", &prop))
> +			panic("RISC-V system with no 'timebase-frequency' in DTS\n");

I appreciate that it was like this before, but a newline here (and in
the corresponding spot below) would be nice.
That's a minor nit though, so:
Reviewed-by: Conor Dooley <conor.dooley@microchip.com>

Thanks,
Conor.

> +		of_node_put(cpu);
> +		riscv_timebase = prop;
> +		of_clk_init(NULL);
> +	} else {
> +		status = acpi_get_table(ACPI_SIG_RHCT, 0, (struct acpi_table_header **)&rhct);
> +		if (ACPI_FAILURE(status))
> +			panic("RISC-V ACPI system with no RHCT table\n");
> +		riscv_timebase = rhct->time_base_freq;
> +		acpi_put_table((struct acpi_table_header *)rhct);
> +	}
>  
>  	lpj_fine = riscv_timebase / HZ;
>  
> -	of_clk_init(NULL);
>  	timer_probe();
>  
>  	tick_setup_hrtimer_broadcast();
> -- 
> 2.34.1
>
Sunil V L March 8, 2023, 9:43 a.m. UTC | #2 
On Mon, Mar 06, 2023 at 09:09:11PM +0000, Conor Dooley wrote:
> On Fri, Mar 03, 2023 at 07:06:44PM +0530, Sunil V L wrote:
> > On ACPI based platforms, timer related information is
> > available in RHCT. Add ACPI based probe support to the
> > timer initialization.
> > 
> > Signed-off-by: Sunil V L <sunilvl@ventanamicro.com>
> > Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
> > Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
> > ---
> >  arch/riscv/kernel/time.c | 23 +++++++++++++++++------
> >  1 file changed, 17 insertions(+), 6 deletions(-)
> > 
> > diff --git a/arch/riscv/kernel/time.c b/arch/riscv/kernel/time.c
> > index babaf3b48ba8..2c29543549c3 100644
> > --- a/arch/riscv/kernel/time.c
> > +++ b/arch/riscv/kernel/time.c
> > @@ -4,6 +4,7 @@
> >   * Copyright (C) 2017 SiFive
> >   */
> >  
> > +#include <linux/acpi.h>
> >  #include <linux/of_clk.h>
> >  #include <linux/clockchips.h>
> >  #include <linux/clocksource.h>
> > @@ -18,17 +19,27 @@ EXPORT_SYMBOL_GPL(riscv_timebase);
> >  void __init time_init(void)
> >  {
> >  	struct device_node *cpu;
> > +	struct acpi_table_rhct *rhct;
> > +	acpi_status status;
> >  	u32 prop;
> >  
> > -	cpu = of_find_node_by_path("/cpus");
> > -	if (!cpu || of_property_read_u32(cpu, "timebase-frequency", &prop))
> > -		panic(KERN_WARNING "RISC-V system with no 'timebase-frequency' in DTS\n");
> > -	of_node_put(cpu);
> > -	riscv_timebase = prop;
> > +	if (acpi_disabled) {
> > +		cpu = of_find_node_by_path("/cpus");
> > +		if (!cpu || of_property_read_u32(cpu, "timebase-frequency", &prop))
> > +			panic("RISC-V system with no 'timebase-frequency' in DTS\n");
> 
> I appreciate that it was like this before, but a newline here (and in
> the corresponding spot below) would be nice.
Sure!. Will update in next revision.

Thanks,
Sunil
diff mbox series

Patch

diff --git a/arch/riscv/kernel/time.c b/arch/riscv/kernel/time.c
index babaf3b48ba8..2c29543549c3 100644
--- a/arch/riscv/kernel/time.c
+++ b/arch/riscv/kernel/time.c
@@ -4,6 +4,7 @@ 
  * Copyright (C) 2017 SiFive
  */
 
+#include <linux/acpi.h>
 #include <linux/of_clk.h>
 #include <linux/clockchips.h>
 #include <linux/clocksource.h>
@@ -18,17 +19,27 @@  EXPORT_SYMBOL_GPL(riscv_timebase);
 void __init time_init(void)
 {
 	struct device_node *cpu;
+	struct acpi_table_rhct *rhct;
+	acpi_status status;
 	u32 prop;
 
-	cpu = of_find_node_by_path("/cpus");
-	if (!cpu || of_property_read_u32(cpu, "timebase-frequency", &prop))
-		panic(KERN_WARNING "RISC-V system with no 'timebase-frequency' in DTS\n");
-	of_node_put(cpu);
-	riscv_timebase = prop;
+	if (acpi_disabled) {
+		cpu = of_find_node_by_path("/cpus");
+		if (!cpu || of_property_read_u32(cpu, "timebase-frequency", &prop))
+			panic("RISC-V system with no 'timebase-frequency' in DTS\n");
+		of_node_put(cpu);
+		riscv_timebase = prop;
+		of_clk_init(NULL);
+	} else {
+		status = acpi_get_table(ACPI_SIG_RHCT, 0, (struct acpi_table_header **)&rhct);
+		if (ACPI_FAILURE(status))
+			panic("RISC-V ACPI system with no RHCT table\n");
+		riscv_timebase = rhct->time_base_freq;
+		acpi_put_table((struct acpi_table_header *)rhct);
+	}
 
 	lpj_fine = riscv_timebase / HZ;
 
-	of_clk_init(NULL);
 	timer_probe();
 
 	tick_setup_hrtimer_broadcast();