pru: Move communication code to second PRU

Perform input and output in the second PRU so that more space is
available in the primary PRU.

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>

1 files changed, 29 insertions, 8 deletions

diff --git a/src/pru/internal.h b/src/pru/internal.h
index b279f3d0..8556eed7 100644
--- a/src/pru/internal.h
+++ b/src/pru/internal.h
@@ -2,17 +2,38 @@
 #define __PRU_INTERNAL_H
 // Local definitions for PRU code
 
-#define IEP_IRQ        0
-#define GOT_ARM_IRQ    1
-#define WAKE_ARM_IRQ   2
+#include <stdint.h> // uint32_t
+
+#define IEP_EVENT                 7
+#define KICK_ARM_EVENT            16
+#define KICK_PRU0_FROM_ARM_EVENT  17
+#define KICK_PRU0_EVENT           18
+#define KICK_PRU1_EVENT           19
 
-#define IEP_EVENT      7
-#define GOT_ARM_EVENT  17
-#define WAKE_ARM_EVENT 16
+#define WAKE_PRU0_IRQ  0
+#define WAKE_PRU1_IRQ  1
+#define WAKE_ARM_IRQ   2
 
 #define R31_IRQ_OFFSET 30
 
-// console.c
-void console_init(void);
+#define R31_WRITE_IRQ_SELECT (1<<5)
+#define R31_WRITE_IRQ_OFFSET 16
+
+// Layout of shared memory
+struct shared_mem {
+    uint32_t signal;
+    uint32_t read_pos, read_count;
+    char read_data[512];
+    uint32_t send_push_pos, send_pop_pos;
+    struct {
+        uint32_t count;
+        char data[64];
+    } send_data[4];
+};
+
+#define SIGNAL_PRU0_WAITING 0xefefefef
+#define SIGNAL_PRU1_READY   0xabababab
+
+static struct shared_mem *SHARED_MEM = (void*)0x10000;
 
 #endif // internal.h