rework structure

hifive1-vp/hello/bsp/include/sifive/devices/plic.h

@@ -0,0 +1,31 @@
+// See LICENSE for license details.
+
+#ifndef PLIC_H
+#define PLIC_H
+
+#include <sifive/const.h>
+
+// 32 bits per source
+#define PLIC_PRIORITY_OFFSET            _AC(0x0000,UL)
+#define PLIC_PRIORITY_SHIFT_PER_SOURCE  2
+// 1 bit per source (1 address)
+#define PLIC_PENDING_OFFSET             _AC(0x1000,UL)
+#define PLIC_PENDING_SHIFT_PER_SOURCE   0
+
+//0x80 per target
+#define PLIC_ENABLE_OFFSET              _AC(0x2000,UL)
+#define PLIC_ENABLE_SHIFT_PER_TARGET    7
+
+
+#define PLIC_THRESHOLD_OFFSET           _AC(0x200000,UL)
+#define PLIC_CLAIM_OFFSET               _AC(0x200004,UL)
+#define PLIC_THRESHOLD_SHIFT_PER_TARGET 12
+#define PLIC_CLAIM_SHIFT_PER_TARGET     12
+
+#define PLIC_MAX_SOURCE                 1023
+#define PLIC_SOURCE_MASK                0x3FF
+
+#define PLIC_MAX_TARGET                 15871
+#define PLIC_TARGET_MASK                0x3FFF
+
+#endif /* PLIC_H */