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#include "io.h"
#include "uart.h"
#include "svc_interface.h"
#include "armclock.h"
#include "scheduler.h"
void __attribute__((noreturn)) setup(void);
// from what I've heard, reset is never used on the Pi;
// in our case it should run once - when stage1 of the kernel
// jumps to stage2
void reset_handler(void)
{
setup();
}
void undefined_instruction_vector(void)
{
error("Undefined instruction occured");
}
uint32_t supervisor_call_handler(uint32_t regs[14])
{
switch(regs[0]) {
case UART_PUTCHAR:
if (putchar_non_blocking(regs[1]))
schedule_wait_for_output(regs, regs[1]);
break;
case UART_GETCHAR:
{
int c;
if ((c = getchar_non_blocking()) == -1)
schedule_wait_for_input(regs);
regs[0] = c;
break;
}
case UART_WRITE:
error("UART_WRITE not implemented!!!!!");
break;
default:
// perhaps we should kill the process now?
error("unknown supervisor call type!!!!!");
}
return 0; // a dummy value
}
void abort_handler(void)
{
// TODO maybe dump registers here?
error("re-entered system due to data/prefetch abort");
}
void generic_handler(void)
{
error("something weird happened");
}
void irq_handler(uint32_t regs[14])
{
if (armclk_irq_pending())
{
write_SPSR(PL1_PSR);
asm volatile("mov r0, %[context]\n\r"
"mov lr, %[return_func]\n\r"
"subs pc, lr, #0" ::
[context]"r" (regs),
[return_func]"r" (schedule_save_context) :
"memory");
}
else if (uart_irq_pending())
{
if (uart_recv_irq_pending())
{
uart_clear_recv_irq();
scheduler_try_input();
}
if (uart_send_irq_pending())
{
uart_clear_send_irq();
scheduler_try_output();
}
if (read_SPSR().fields.PSR_MODE_4_0 != MODE_USER)
{
write_SPSR(PL1_PSR);
asm volatile("mov lr, %0\n\r"
"subs pc, lr, #0" ::
"r" (schedule) : "memory");
}
}
else
error("unknown irq");
// important - don't allow this handler to return if irq came from
// PL1 (likely supervisor, because we don't really use system) mode
}
void fiq_handler(void)
{
error("fiq happened");
}
/* Old, not sure if working interrupt function */
//void
//__attribute__((interrupt("IRQ")))
//__attribute__((section(".interrupt_vectors.text")))
//irq_handler2(void) {
//// uart_puts("GOT INTERRUPT!\r\n");
//
// local_timer_clr_reload_reg_t temp = { .IntClear = 1, .Reload = 1 };
// QA7->TimerClearReload = temp; // Clear interrupt & reload
//}
//int enable_timer(void) {
//
// QA7->TimerRouting.Routing = LOCALTIMER_TO_CORE0_IRQ; // Route local timer IRQ to Core0
// QA7->TimerControlStatus.ReloadValue = 100; // Timer period set
// QA7->TimerControlStatus.TimerEnable = 1; // Timer enabled
// QA7->TimerControlStatus.IntEnable = 1; // Timer IRQ enabled
// QA7->TimerClearReload.IntClear = 1; // Clear interrupt
// QA7->TimerClearReload.Reload = 1; // Reload now
// QA7->Core0TimerIntControl.nCNTPNSIRQ_IRQ = 1; // We are in NS EL1 so enable IRQ to core0 that level
// QA7->Core0TimerIntControl.nCNTPNSIRQ_FIQ = 0; // Make sure FIQ is zero
//// uart_puts("Enabled Timer\r\n");
// return(0);
//}
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