opensbi/lib/sbi/sbi_timer.c

137 lines
2.9 KiB
C

/*
* SPDX-License-Identifier: BSD-2-Clause
*
* Copyright (c) 2019 Western Digital Corporation or its affiliates.
*
* Authors:
* Anup Patel <anup.patel@wdc.com>
*/
#include <sbi/riscv_asm.h>
#include <sbi/riscv_encoding.h>
#include <sbi/sbi_error.h>
#include <sbi/sbi_hart.h>
#include <sbi/sbi_platform.h>
#include <sbi/sbi_scratch.h>
#include <sbi/sbi_timer.h>
static unsigned long time_delta_off;
static u64 (*get_time_val)(const struct sbi_platform *plat);
#if __riscv_xlen == 32
static u64 get_ticks(const struct sbi_platform *plat)
{
u32 lo, hi, tmp;
__asm__ __volatile__("1:\n"
"rdtimeh %0\n"
"rdtime %1\n"
"rdtimeh %2\n"
"bne %0, %2, 1b"
: "=&r"(hi), "=&r"(lo), "=&r"(tmp));
return ((u64)hi << 32) | lo;
}
#else
static u64 get_ticks(const struct sbi_platform *plat)
{
unsigned long n;
__asm__ __volatile__("rdtime %0" : "=r"(n));
return n;
}
#endif
u64 sbi_timer_value(void)
{
return get_time_val(sbi_platform_thishart_ptr());
}
u64 sbi_timer_virt_value(void)
{
u64 *time_delta = sbi_scratch_offset_ptr(sbi_scratch_thishart_ptr(),
time_delta_off);
return sbi_timer_value() + *time_delta;
}
u64 sbi_timer_get_delta(void)
{
u64 *time_delta = sbi_scratch_offset_ptr(sbi_scratch_thishart_ptr(),
time_delta_off);
return *time_delta;
}
void sbi_timer_set_delta(ulong delta)
{
u64 *time_delta = sbi_scratch_offset_ptr(sbi_scratch_thishart_ptr(),
time_delta_off);
*time_delta = (u64)delta;
}
void sbi_timer_set_delta_upper(ulong delta_upper)
{
u64 *time_delta = sbi_scratch_offset_ptr(sbi_scratch_thishart_ptr(),
time_delta_off);
*time_delta &= 0xffffffffULL;
*time_delta |= ((u64)delta_upper << 32);
}
void sbi_timer_event_start(u64 next_event)
{
sbi_platform_timer_event_start(sbi_platform_thishart_ptr(), next_event);
csr_clear(CSR_MIP, MIP_STIP);
csr_set(CSR_MIE, MIP_MTIP);
}
void sbi_timer_process(void)
{
csr_clear(CSR_MIE, MIP_MTIP);
csr_set(CSR_MIP, MIP_STIP);
}
int sbi_timer_init(struct sbi_scratch *scratch, bool cold_boot)
{
u64 *time_delta;
const struct sbi_platform *plat = sbi_platform_ptr(scratch);
int ret;
if (cold_boot) {
time_delta_off = sbi_scratch_alloc_offset(sizeof(*time_delta),
"TIME_DELTA");
if (!time_delta_off)
return SBI_ENOMEM;
} else {
if (!time_delta_off)
return SBI_ENOMEM;
}
time_delta = sbi_scratch_offset_ptr(scratch, time_delta_off);
*time_delta = 0;
ret = sbi_platform_timer_init(plat, cold_boot);
if (ret)
return ret;
if (sbi_hart_has_feature(scratch, SBI_HART_HAS_TIME))
get_time_val = get_ticks;
else if (sbi_platform_has_timer_value(plat))
get_time_val = sbi_platform_timer_value;
else
/* There is no method to provide timer value */
return SBI_ENODEV;
return 0;
}
void sbi_timer_exit(struct sbi_scratch *scratch)
{
sbi_platform_timer_event_stop(sbi_platform_ptr(scratch));
csr_clear(CSR_MIP, MIP_STIP);
csr_clear(CSR_MIE, MIP_MTIP);
sbi_platform_timer_exit(sbi_platform_ptr(scratch));
}