From 43942973cd9b61dc94bb52be53a99f8ca711eb7e Mon Sep 17 00:00:00 2001 From: Megan Wachs Date: Tue, 31 Jan 2017 19:02:18 -0800 Subject: Move plic_driver code to a common location. --- bsp/drivers/plic/plic_driver.c | 127 +++++++++++++++++++++++++++++++++++++++++ bsp/drivers/plic/plic_driver.h | 46 +++++++++++++++ 2 files changed, 173 insertions(+) create mode 100644 bsp/drivers/plic/plic_driver.c create mode 100644 bsp/drivers/plic/plic_driver.h (limited to 'bsp/drivers') diff --git a/bsp/drivers/plic/plic_driver.c b/bsp/drivers/plic/plic_driver.c new file mode 100644 index 0000000..b27d7a5 --- /dev/null +++ b/bsp/drivers/plic/plic_driver.c @@ -0,0 +1,127 @@ +// See LICENSE for license details. + +#include "sifive/devices/plic.h" +#include "plic/plic_driver.h" +#include "platform.h" +#include "encoding.h" +#include + + +// 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; + +} + diff --git a/bsp/drivers/plic/plic_driver.h b/bsp/drivers/plic/plic_driver.h new file mode 100644 index 0000000..66410be --- /dev/null +++ b/bsp/drivers/plic/plic_driver.h @@ -0,0 +1,46 @@ +// See LICENSE file for licence details + +#ifndef PLIC_DRIVER_H +#define PLIC_DRIVER_H + +#include "platform.h" + +typedef struct __plic_instance_t +{ + uintptr_t base_addr; + + uint32_t num_sources; + uint32_t num_priorities; + +} plic_instance_t; + +typedef uint32_t plic_source; +typedef uint32_t plic_priority; +typedef uint32_t plic_threshold; + +void PLIC_init ( + plic_instance_t * this_plic, + uintptr_t base_addr, + uint32_t num_sources, + uint32_t num_priorities + ); + +void PLIC_set_threshold (plic_instance_t * this_plic, + plic_threshold threshold); + +void PLIC_enable_interrupt (plic_instance_t * this_plic, + plic_source source); + +void PLIC_disable_interrupt (plic_instance_t * this_plic, + plic_source source); + +void PLIC_set_priority (plic_instance_t * this_plic, + plic_source source, + plic_priority priority); + +plic_source PLIC_claim_interrupt(plic_instance_t * this_plic); + +void PLIC_complete_interrupt(plic_instance_t * this_plic, + plic_source source); + +#endif -- cgit v1.2.3