Hi Jingyi, On 7/2/20 5:01 AM, Jingyi Wang wrote: > Trigger PPIs by setting up a 10msec timer and test the latency. so for each iteration the accumulated valued is 10 ms + latency, right? and what is printed at the end does include the accumulated periods. Wouldn't it make sense to have a test->post() that substract this value. You would need to store the actual number of iterations. Thanks Eric > > Signed-off-by: Jingyi Wang <wangjingyi11@xxxxxxxxxx> > --- > arm/micro-bench.c | 56 ++++++++++++++++++++++++++++++++++++++++++++++- > 1 file changed, 55 insertions(+), 1 deletion(-) > > diff --git a/arm/micro-bench.c b/arm/micro-bench.c > index 4c962b7..6822084 100644 > --- a/arm/micro-bench.c > +++ b/arm/micro-bench.c > @@ -23,8 +23,13 @@ > #include <asm/gic-v3-its.h> > > #define NTIMES (1U << 16) > +#define NTIMES_MINOR (1U << 8) > #define MAX_NS (5 * 1000 * 1000 * 1000UL) > > +#define IRQ_VTIMER 27 > +#define ARCH_TIMER_CTL_ENABLE (1 << 0) > +#define ARCH_TIMER_CTL_IMASK (1 << 1) > + > static u32 cntfrq; > > static volatile bool irq_ready, irq_received; > @@ -33,9 +38,16 @@ static void (*write_eoir)(u32 irqstat); > > static void gic_irq_handler(struct pt_regs *regs) > { > + u32 irqstat = gic_read_iar(); > irq_ready = false; > irq_received = true; > - gic_write_eoir(gic_read_iar()); > + gic_write_eoir(irqstat); > + > + if (irqstat == IRQ_VTIMER) { > + write_sysreg((ARCH_TIMER_CTL_IMASK | ARCH_TIMER_CTL_ENABLE), > + cntv_ctl_el0); > + isb(); > + } > irq_ready = true; > } > > @@ -189,6 +201,47 @@ static void lpi_exec(void) > assert_msg(irq_received, "failed to receive LPI in time, but received %d successfully\n", received); > } > > +static bool timer_prep(void) > +{ > + static void *gic_isenabler; > + > + gic_enable_defaults(); > + install_irq_handler(EL1H_IRQ, gic_irq_handler); > + local_irq_enable(); > + > + gic_isenabler = gicv3_sgi_base() + GICR_ISENABLER0; > + writel(1 << 27, gic_isenabler); > + write_sysreg(ARCH_TIMER_CTL_ENABLE, cntv_ctl_el0); > + isb(); > + > + gic_prep_common(); > + return true; > +} > + > +static void timer_exec(void) > +{ > + u64 before_timer; > + u64 timer_10ms; > + unsigned tries = 1 << 28; > + static int received = 0; > + > + irq_received = false; > + > + before_timer = read_sysreg(cntvct_el0); > + timer_10ms = cntfrq / 100; > + write_sysreg(before_timer + timer_10ms, cntv_cval_el0); > + write_sysreg(ARCH_TIMER_CTL_ENABLE, cntv_ctl_el0); > + isb(); > + > + while (!irq_received && tries--) > + cpu_relax(); > + > + if (irq_received) > + ++received; > + > + assert_msg(irq_received, "failed to receive PPI in time, but received %d successfully\n", received); > +} > + > static void hvc_exec(void) > { > asm volatile("mov w0, #0x4b000000; hvc #0" ::: "w0"); > @@ -236,6 +289,7 @@ static struct exit_test tests[] = { > {"ipi", ipi_prep, ipi_exec, NTIMES, true}, > {"ipi_hw", ipi_hw_prep, ipi_exec, NTIMES, true}, > {"lpi", lpi_prep, lpi_exec, NTIMES, true}, > + {"timer_10ms", timer_prep, timer_exec, NTIMES_MINOR, true}, > }; > > struct ns_time { >