FreeRTOS-RISCV/RISC-V-HiFive1_e-FreedomStudio/freedom-e-sdk/drivers/plic/plic_driver.c

128 lines
4.3 KiB
C
Raw Permalink Normal View History

2019-06-28 23:08:36 +02:00
// See LICENSE for license details.
#include "sifive/devices/plic.h"
#include "plic/plic_driver.h"
#include "platform.h"
#include "encoding.h"
#include <string.h>
// Note that there are no assertions or bounds checking on these
// parameter values.
void volatile_memzero(uint8_t * base, unsigned int size)
{
volatile uint8_t * ptr;
for (ptr = base; ptr < (base + size); ptr++){
*ptr = 0;
}
}
void PLIC_init (
plic_instance_t * this_plic,
uintptr_t base_addr,
uint32_t num_sources,
uint32_t num_priorities
)
{
this_plic->base_addr = base_addr;
this_plic->num_sources = num_sources;
this_plic->num_priorities = num_priorities;
// Disable all interrupts (don't assume that these registers are reset).
unsigned long hart_id = read_csr(mhartid);
volatile_memzero((uint8_t*) (this_plic->base_addr +
PLIC_ENABLE_OFFSET +
(hart_id << PLIC_ENABLE_SHIFT_PER_TARGET)),
(num_sources + 8) / 8);
// Set all priorities to 0 (equal priority -- don't assume that these are reset).
volatile_memzero ((uint8_t *)(this_plic->base_addr +
PLIC_PRIORITY_OFFSET),
(num_sources + 1) << PLIC_PRIORITY_SHIFT_PER_SOURCE);
// Set the threshold to 0.
volatile plic_threshold* threshold = (plic_threshold*)
(this_plic->base_addr +
PLIC_THRESHOLD_OFFSET +
(hart_id << PLIC_THRESHOLD_SHIFT_PER_TARGET));
*threshold = 0;
}
void PLIC_set_threshold (plic_instance_t * this_plic,
plic_threshold threshold){
unsigned long hart_id = read_csr(mhartid);
volatile plic_threshold* threshold_ptr = (plic_threshold*) (this_plic->base_addr +
PLIC_THRESHOLD_OFFSET +
(hart_id << PLIC_THRESHOLD_SHIFT_PER_TARGET));
*threshold_ptr = threshold;
}
void PLIC_enable_interrupt (plic_instance_t * this_plic, plic_source source){
unsigned long hart_id = read_csr(mhartid);
volatile uint8_t * current_ptr = (volatile uint8_t *)(this_plic->base_addr +
PLIC_ENABLE_OFFSET +
(hart_id << PLIC_ENABLE_SHIFT_PER_TARGET) +
(source >> 3));
uint8_t current = *current_ptr;
current = current | ( 1 << (source & 0x7));
*current_ptr = current;
}
void PLIC_disable_interrupt (plic_instance_t * this_plic, plic_source source){
unsigned long hart_id = read_csr(mhartid);
volatile uint8_t * current_ptr = (volatile uint8_t *) (this_plic->base_addr +
PLIC_ENABLE_OFFSET +
(hart_id << PLIC_ENABLE_SHIFT_PER_TARGET) +
(source >> 3));
uint8_t current = *current_ptr;
current = current & ~(( 1 << (source & 0x7)));
*current_ptr = current;
}
void PLIC_set_priority (plic_instance_t * this_plic, plic_source source, plic_priority priority){
if (this_plic->num_priorities > 0) {
volatile plic_priority * priority_ptr = (volatile plic_priority *)
(this_plic->base_addr +
PLIC_PRIORITY_OFFSET +
(source << PLIC_PRIORITY_SHIFT_PER_SOURCE));
*priority_ptr = priority;
}
}
plic_source PLIC_claim_interrupt(plic_instance_t * this_plic){
unsigned long hart_id = read_csr(mhartid);
volatile plic_source * claim_addr = (volatile plic_source * )
(this_plic->base_addr +
PLIC_CLAIM_OFFSET +
(hart_id << PLIC_CLAIM_SHIFT_PER_TARGET));
return *claim_addr;
}
void PLIC_complete_interrupt(plic_instance_t * this_plic, plic_source source){
unsigned long hart_id = read_csr(mhartid);
volatile plic_source * claim_addr = (volatile plic_source *) (this_plic->base_addr +
PLIC_CLAIM_OFFSET +
(hart_id << PLIC_CLAIM_SHIFT_PER_TARGET));
*claim_addr = source;
}