Files
linux-kernel-module-cheat/baremetal/arch/aarch64/timer.c
Ciro Santilli 六四事件 法轮功 b38e2b0da9 arm baremetal: SVC explain where the imm16 can be retrieved
Use upper case hex literals on all PRIXnn.

.gitignore /out.docker
2019-07-16 00:00:01 +00:00

74 lines
2.4 KiB
C

#include <stdio.h>
#include <inttypes.h>
#include <lkmc.h>
#include <lkmc/gicv3.h>
void lkmc_vector_trap_handler(LkmcVectorExceptionFrame *exception __attribute__((unused))) {
printf("CNTVCT_EL0 0x%" PRIX64 "\n", lkmc_sysreg_cntvct_el0_read());
}
#define CNTV_CTL_ENABLE (1 << 0) /* Enables the timer */
#define CNTV_CTL_IMASK (1 << 1) /* Timer interrupt mask bit */
#define CNTV_CTL_ISTATUS (1 << 2) /* The status of the timer interrupt. This bit is read-only */
/* DAIF, Interrupt Mask Bits */
#define DAIF_DBG_BIT (1<<3) /* Debug mask bit */
#define DAIF_ABT_BIT (1<<2) /* Asynchronous abort mask bit */
#define DAIF_IRQ_BIT (1<<1) /* IRQ mask bit */
#define DAIF_FIQ_BIT (1<<0) /* FIQ mask bit */
#define wfi() __asm__ __volatile__ ("wfi" : : : "memory")
void enable_cntv(void) {
lkmc_sysreg_cntv_ctl_el0_write(lkmc_sysreg_cntv_ctl_el0_read() | CNTV_CTL_ENABLE);
}
void enable_irq(void) {
__asm__ __volatile__ ("msr DAIFClr, %0" : : "i" (DAIF_IRQ_BIT) : "memory");
}
int main(void) {
/* Initial state. */
printf("CNTV_CTL_EL0 0x%" PRIX32 "\n", lkmc_sysreg_cntv_ctl_el0_read());
printf("CNTFRQ_EL0 0x%" PRIX64 "\n", lkmc_sysreg_cntfrq_el0_read());
printf("CNTV_CVAL_EL0 0x%" PRIX64 "\n", lkmc_sysreg_cntv_cval_el0_read());
/* Get the counter value many times to watch the time pass. */
printf("CNTVCT_EL0 0x%" PRIX64 "\n", lkmc_sysreg_cntvct_el0_read());
printf("CNTVCT_EL0 0x%" PRIX64 "\n", lkmc_sysreg_cntvct_el0_read());
printf("CNTVCT_EL0 0x%" PRIX64 "\n", lkmc_sysreg_cntvct_el0_read());
/**/
gic_v3_initialize();
{
uint64_t ticks, current_cnt;
uint32_t cntfrq;
cntfrq = lkmc_sysreg_cntfrq_el0_read();
ticks = cntfrq;
current_cnt = lkmc_sysreg_cntvct_el0_read();
lkmc_sysreg_cntv_cval_el0_write(current_cnt + ticks);
enable_cntv();
enable_irq();
}
while (1) {
/*puts("qwer");*/
/*current_cnt = raw_read_cntvct_el0();*/
/*val = raw_read_cntv_ctl();*/
/*printf("CNTVCT_EL0 = ");*/
/*uart_puthex(current_cnt);*/
/*uart_puts(", CNTV_CTL_EL0 = ");*/
/*uart_puthex(val);*/
/*wfi();*/
}
#if 0
/* TODO crashes gem5. */
puts("cntfrq_el0 = 1");
lkmc_sysreg_cntfrq_el0_write(1);
printf("cntfrq_el0 0x%" PRIX64 "\n", lkmc_sysreg_cntfrq_el0_read());
#endif
return 0;
}