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/***************************************************************************
* Copyright (c) 2026 10xEngineers
*
* This program and the accompanying materials are made available under the
* terms of the MIT License which is available at
* https://opensource.org/licenses/MIT.
*
* SPDX-License-Identifier: MIT
**************************************************************************/
#ifndef RISCV_HWTIMER_H
#define RISCV_HWTIMER_H
#include <stdint.h>
/* SpacemiT K1 TIMER (S-mode via SBI ecall)
*
* In S-mode the CLINT MMIO registers (mtime / mtimecmp) are protected
* by PMP and inaccessible. Timer operations are performed through the
* SBI legacy interface.
*
* rdtime - pseudo-instruction reading the time CSR (aliased to mtime
* by the implementation; accessible from S-mode per Priv
* Spec).
*
* SBI legacy set_timer (EID = 0, FID = 0) - programs mtimecmp on
* the current hart. Argument a0 = absolute compare value.
* Clears the pending supervisor timer interrupt (sip.STIP)
* as a side effect.
*
*
* Timebase frequency (DTS cpus { timebase-frequency = <0x16e3600>; }):
* 24,000,000 Hz (24 MHz).
*
* ThreadX tick rate: 10 Hz (100 ms period).
*/
#define TICKNUM_PER_SECOND 24000000UL
#define TICKNUM_PER_TIMER (TICKNUM_PER_SECOND / 10)
int hwtimer_init(void);
int hwtimer_handler(void);
#endif /* RISCV_HWTIMER_H */
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