| 1 | // SPDX-License-Identifier: GPL-2.0-only |
|---|---|
| 2 | /* |
| 3 | * Copyright (C) 2012 Regents of the University of California |
| 4 | * Copyright (C) 2017 SiFive |
| 5 | */ |
| 6 | |
| 7 | #include <linux/acpi.h> |
| 8 | #include <linux/of_clk.h> |
| 9 | #include <linux/clockchips.h> |
| 10 | #include <linux/clocksource.h> |
| 11 | #include <linux/delay.h> |
| 12 | #include <asm/sbi.h> |
| 13 | #include <asm/processor.h> |
| 14 | #include <asm/timex.h> |
| 15 | #include <asm/paravirt.h> |
| 16 | |
| 17 | unsigned long riscv_timebase __ro_after_init; |
| 18 | EXPORT_SYMBOL_GPL(riscv_timebase); |
| 19 | |
| 20 | void __init time_init(void) |
| 21 | { |
| 22 | struct device_node *cpu; |
| 23 | struct acpi_table_rhct *rhct; |
| 24 | acpi_status status; |
| 25 | u32 prop; |
| 26 | |
| 27 | if (acpi_disabled) { |
| 28 | cpu = of_find_node_by_path(path: "/cpus"); |
| 29 | if (!cpu || of_property_read_u32(np: cpu, propname: "timebase-frequency", out_value: &prop)) |
| 30 | panic(fmt: "RISC-V system with no 'timebase-frequency' in DTS\n"); |
| 31 | |
| 32 | of_node_put(node: cpu); |
| 33 | riscv_timebase = prop; |
| 34 | of_clk_init(NULL); |
| 35 | } else { |
| 36 | status = acpi_get_table(ACPI_SIG_RHCT, instance: 0, out_table: (struct acpi_table_header **)&rhct); |
| 37 | if (ACPI_FAILURE(status)) |
| 38 | panic(fmt: "RISC-V ACPI system with no RHCT table\n"); |
| 39 | |
| 40 | riscv_timebase = rhct->time_base_freq; |
| 41 | acpi_put_table(table: (struct acpi_table_header *)rhct); |
| 42 | } |
| 43 | |
| 44 | lpj_fine = riscv_timebase / HZ; |
| 45 | |
| 46 | timer_probe(); |
| 47 | |
| 48 | tick_setup_hrtimer_broadcast(); |
| 49 | |
| 50 | pv_time_init(); |
| 51 | } |
| 52 |