Orange Pi5 kernel

// SPDX-License-Identifier: GPL-2.0
#include <errno.h>
 
#include <linux/compiler.h>
#include <linux/perf_event.h>
#include <linux/stddef.h>
#include <linux/types.h>
 
#include <asm/barrier.h>
 
#include "event.h"
#include "synthetic-events.h"
#include "debug.h"
#include "tsc.h"
 
u64 perf_time_to_tsc(u64 ns, struct perf_tsc_conversion *tc)
{
<------>u64 t, quot, rem;
 
<------>t = ns - tc->time_zero;
<------>quot = t / tc->time_mult;
<------>rem  = t % tc->time_mult;
<------>return (quot << tc->time_shift) +
<------>       (rem << tc->time_shift) / tc->time_mult;
}
 
u64 tsc_to_perf_time(u64 cyc, struct perf_tsc_conversion *tc)
{
<------>u64 quot, rem;
 
<------>if (tc->cap_user_time_short)
<------><------>cyc = tc->time_cycles +
<------><------><------>((cyc - tc->time_cycles) & tc->time_mask);
 
<------>quot = cyc >> tc->time_shift;
<------>rem  = cyc & (((u64)1 << tc->time_shift) - 1);
<------>return tc->time_zero + quot * tc->time_mult +
<------>       ((rem * tc->time_mult) >> tc->time_shift);
}
 
int perf_read_tsc_conversion(const struct perf_event_mmap_page *pc,
<------><------><------>     struct perf_tsc_conversion *tc)
{
<------>u32 seq;
<------>int i = 0;
 
<------>while (1) {
<------><------>seq = pc->lock;
<------><------>rmb();
<------><------>tc->time_mult = pc->time_mult;
<------><------>tc->time_shift = pc->time_shift;
<------><------>tc->time_zero = pc->time_zero;
<------><------>tc->time_cycles = pc->time_cycles;
<------><------>tc->time_mask = pc->time_mask;
<------><------>tc->cap_user_time_zero = pc->cap_user_time_zero;
<------><------>tc->cap_user_time_short	= pc->cap_user_time_short;
<------><------>rmb();
<------><------>if (pc->lock == seq && !(seq & 1))
<------><------><------>break;
<------><------>if (++i > 10000) {
<------><------><------>pr_debug("failed to get perf_event_mmap_page lock\n");
<------><------><------>return -EINVAL;
<------><------>}
<------>}
 
<------>if (!tc->cap_user_time_zero)
<------><------>return -EOPNOTSUPP;
 
<------>return 0;
}
 
int perf_event__synth_time_conv(const struct perf_event_mmap_page *pc,
<------><------><------><------>struct perf_tool *tool,
<------><------><------><------>perf_event__handler_t process,
<------><------><------><------>struct machine *machine)
{
<------>union perf_event event = {
<------><------>.time_conv = {
<------><------><------>.header = {
<------><------><------><------>.type = PERF_RECORD_TIME_CONV,
<------><------><------><------>.size = sizeof(struct perf_record_time_conv),
<------><------><------>},
<------><------>},
<------>};
<------>struct perf_tsc_conversion tc;
<------>int err;
 
<------>if (!pc)
<------><------>return 0;
<------>err = perf_read_tsc_conversion(pc, &tc);
<------>if (err == -EOPNOTSUPP)
<------><------>return 0;
<------>if (err)
<------><------>return err;
 
<------>pr_debug2("Synthesizing TSC conversion information\n");
 
<------>event.time_conv.time_mult  = tc.time_mult;
<------>event.time_conv.time_shift = tc.time_shift;
<------>event.time_conv.time_zero  = tc.time_zero;
<------>event.time_conv.time_cycles = tc.time_cycles;
<------>event.time_conv.time_mask = tc.time_mask;
<------>event.time_conv.cap_user_time_zero = tc.cap_user_time_zero;
<------>event.time_conv.cap_user_time_short = tc.cap_user_time_short;
 
<------>return process(tool, &event, NULL, machine);
}
 
u64 __weak rdtsc(void)
{
<------>return 0;
}