49 lines
1.1 KiB
C
49 lines
1.1 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* Copyright (C) 2012 Regents of the University of California
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* Copyright (C) 2017 SiFive
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*/
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#include <linux/acpi.h>
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#include <linux/of_clk.h>
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#include <linux/clockchips.h>
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#include <linux/clocksource.h>
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#include <linux/delay.h>
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#include <asm/sbi.h>
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#include <asm/processor.h>
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#include <asm/timex.h>
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unsigned long riscv_timebase __ro_after_init;
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EXPORT_SYMBOL_GPL(riscv_timebase);
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void __init time_init(void)
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{
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struct device_node *cpu;
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struct acpi_table_rhct *rhct;
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acpi_status status;
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u32 prop;
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if (acpi_disabled) {
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cpu = of_find_node_by_path("/cpus");
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if (!cpu || of_property_read_u32(cpu, "timebase-frequency", &prop))
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panic("RISC-V system with no 'timebase-frequency' in DTS\n");
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of_node_put(cpu);
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riscv_timebase = prop;
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of_clk_init(NULL);
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} else {
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status = acpi_get_table(ACPI_SIG_RHCT, 0, (struct acpi_table_header **)&rhct);
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if (ACPI_FAILURE(status))
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panic("RISC-V ACPI system with no RHCT table\n");
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riscv_timebase = rhct->time_base_freq;
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acpi_put_table((struct acpi_table_header *)rhct);
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}
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lpj_fine = riscv_timebase / HZ;
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timer_probe();
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tick_setup_hrtimer_broadcast();
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}
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