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