diff options
Diffstat (limited to 'lib/sbi/sbi_timer.c')
| -rw-r--r-- | lib/sbi/sbi_timer.c | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/lib/sbi/sbi_timer.c b/lib/sbi/sbi_timer.c index 2759501..acdba92 100644 --- a/lib/sbi/sbi_timer.c +++ b/lib/sbi/sbi_timer.c @@ -8,7 +8,9 @@ */ #include <sbi/riscv_asm.h> +#include <sbi/riscv_barrier.h> #include <sbi/riscv_encoding.h> +#include <sbi/sbi_console.h> #include <sbi/sbi_error.h> #include <sbi/sbi_hart.h> #include <sbi/sbi_platform.h> @@ -47,6 +49,38 @@ static u64 get_platform_ticks(void) return timer_dev->timer_value(); } +static void nop_delay_fn(void *opaque) +{ + cpu_relax(); +} + +void sbi_timer_delay_loop(ulong units, u64 unit_freq, + void (*delay_fn)(void *), void *opaque) +{ + u64 start_val, delta; + + /* Do nothing if we don't have timer device */ + if (!timer_dev || !get_time_val) { + sbi_printf("%s: called without timer device\n", __func__); + return; + } + + /* Save starting timer value */ + start_val = get_time_val(); + + /* Compute desired timer value delta */ + delta = ((u64)timer_dev->timer_freq * (u64)units); + delta = delta / unit_freq; + + /* Use NOP delay function if delay function not available */ + if (!delay_fn) + delay_fn = nop_delay_fn; + + /* Busy loop until desired timer value delta reached */ + while ((get_time_val() - start_val) < delta) + delay_fn(opaque); +} + u64 sbi_timer_value(void) { if (get_time_val) |