Unverified Commit 714aa1d1 authored by Sunil V L's avatar Sunil V L Committed by Palmer Dabbelt
Browse files

RISC-V: time.c: Add ACPI support for time_init() 



On ACPI based platforms, timer related information is
available in RHCT. Add ACPI based probe support to the
timer initialization.

Signed-off-by: default avatarSunil V L <sunilvl@ventanamicro.com>
Acked-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: default avatarAndrew Jones <ajones@ventanamicro.com>
Reviewed-by: default avatarConor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20230515054928.2079268-20-sunilvl@ventanamicro.com


Signed-off-by: default avatarPalmer Dabbelt <palmer@rivosinc.com>
parent 21f4f924

arch/riscv/kernel/time.c

+19 −6
Original line number Diff line number Diff line
@@ -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 +19,29 @@ EXPORT_SYMBOL_GPL(riscv_timebase); 
void __init time_init(void)

{

	struct device_node *cpu;

	struct acpi_table_rhct *rhct;

	acpi_status status;

	u32 prop;



	if (acpi_disabled) {

		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");

			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();