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authorMegan Wachs <megan@sifive.com>2017-02-02 11:40:13 -0800
committerGitHub <noreply@github.com>2017-02-02 11:40:13 -0800
commitb7c778c4e0b26e719226053a204142c0cb54dd4b (patch)
tree88405c74373d0d04da351aff5f2cf92dcf11d2a9 /bsp/drivers/plic
parent55136a72df6f6f64793be7ead298434d01721dc5 (diff)
parent557c3ed0dc025b73a919f3e2a4068808092f48c1 (diff)
Merge pull request #50 from sifive/common_plic
FE-203 Move plic_driver code to a common location.
Diffstat (limited to 'bsp/drivers/plic')
-rw-r--r--bsp/drivers/plic/plic_driver.c127
-rw-r--r--bsp/drivers/plic/plic_driver.h51
2 files changed, 178 insertions, 0 deletions
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 <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;
+
+}
+
diff --git a/bsp/drivers/plic/plic_driver.h b/bsp/drivers/plic/plic_driver.h
new file mode 100644
index 0000000..e7d609b
--- /dev/null
+++ b/bsp/drivers/plic/plic_driver.h
@@ -0,0 +1,51 @@
+// See LICENSE file for licence details
+
+#ifndef PLIC_DRIVER_H
+#define PLIC_DRIVER_H
+
+
+__BEGIN_DECLS
+
+#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);
+
+__END_DECLS
+
+#endif