pbio/drv/i2c/i2c_ev3.c: Add interrupt handlers

The PRU uses these events to inform the ARM of completion
(both success and failure).

Author: ArcaneNibble

lib/pbio/drv/i2c/i2c_ev3.c

@@ -10,13 +10,20 @@
 #include <stdbool.h>
 #include <stdint.h>
 #include <stdio.h>
+#include <string.h>
 
-#include <pbdrv/gpio.h>
+#include <tiam1808/armv5/am1808/interrupt.h>
+#include <tiam1808/hw/hw_types.h>
+#include <tiam1808/pruss.h>
+
+#include <pbio/busy_count.h>
 #include <pbio/error.h>
+#include <pbio/os.h>
 #include <pbio/util.h>
 
 #include <pbdrv/i2c.h>
 
+#include "../drv/rproc/rproc.h"
 #include "../rproc/rproc_ev3.h"
 
 #define DEBUG 1
@@ -32,13 +39,21 @@
 #endif
 
 struct _pbdrv_i2c_dev_t {
+    volatile bool is_busy;
     bool is_initialized;
     uint8_t pru_i2c_idx;
 };
 
 static pbdrv_i2c_dev_t i2c_devs[PBDRV_CONFIG_I2C_EV3_NUM_DEV];
 _Static_assert(PBDRV_CONFIG_I2C_EV3_NUM_DEV <= PBDRV_RPROC_EV3_PRU1_NUM_I2C_BUSES);
 
+enum {
+    PRU_I2C_PORT1_EVT = 42,
+    PRU_I2C_PORT2_EVT = 44,
+    PRU_I2C_PORT3_EVT = 46,
+    PRU_I2C_PORT4_EVT = 48,
+};
+
 pbio_error_t pbdrv_i2c_get_instance(uint8_t id, pbdrv_i2c_dev_t **i2c_dev) {
     if (id >= PBDRV_CONFIG_I2C_EV3_NUM_DEV) {
         return PBIO_ERROR_INVALID_ARG;
@@ -52,17 +67,80 @@ pbio_error_t pbdrv_i2c_get_instance(uint8_t id, pbdrv_i2c_dev_t **i2c_dev) {
     return PBIO_SUCCESS;
 }
 
+static void pbdrv_i2c_irq_0(void) {
+    IntSystemStatusClear(SYS_INT_EVTOUT4);
+    HWREG(INTC_PHYS_BASE + PRU_INTC_SICR_REG) = PRU_I2C_PORT1_EVT;
+    i2c_devs[0].is_busy = false;
+    pbio_os_request_poll();
+}
+static void pbdrv_i2c_irq_1(void) {
+    IntSystemStatusClear(SYS_INT_EVTOUT5);
+    HWREG(INTC_PHYS_BASE + PRU_INTC_SICR_REG) = PRU_I2C_PORT2_EVT;
+    i2c_devs[1].is_busy = false;
+    pbio_os_request_poll();
+}
+static void pbdrv_i2c_irq_2(void) {
+    IntSystemStatusClear(SYS_INT_EVTOUT6);
+    HWREG(INTC_PHYS_BASE + PRU_INTC_SICR_REG) = PRU_I2C_PORT3_EVT;
+    i2c_devs[2].is_busy = false;
+    pbio_os_request_poll();
+}
+static void pbdrv_i2c_irq_3(void) {
+    IntSystemStatusClear(SYS_INT_EVTOUT7);
+    HWREG(INTC_PHYS_BASE + PRU_INTC_SICR_REG) = PRU_I2C_PORT4_EVT;
+    i2c_devs[3].is_busy = false;
+    pbio_os_request_poll();
+}
+
 pbio_error_t pbdrv_i2c_placeholder_operation(pbdrv_i2c_dev_t *i2c_dev, const char *operation) {
     debug_pr("I2C placeholder operation %s\n", operation);
     return PBIO_SUCCESS;
 }
 
+static pbio_os_process_t ev3_i2c_init_process;
+
+pbio_error_t ev3_i2c_init_process_thread(pbio_os_state_t *state, void *context) {
+    PBIO_OS_ASYNC_BEGIN(state);
+
+    // Need rproc to be initialized, because it sets up the PRU INTC
+    PBIO_OS_AWAIT_UNTIL(state, pbdrv_rproc_is_ready());
+
+    // REVISIT: These event numbers get set up by the SUART library.
+    // We should separate them cleanly in the future.
+    IntRegister(SYS_INT_EVTOUT4, pbdrv_i2c_irq_0);
+    IntChannelSet(SYS_INT_EVTOUT4, 2);
+    IntSystemEnable(SYS_INT_EVTOUT4);
+    HWREG(INTC_PHYS_BASE + PRU_INTC_EISR_REG) = PRU_I2C_PORT1_EVT;
+
+    IntRegister(SYS_INT_EVTOUT5, pbdrv_i2c_irq_1);
+    IntChannelSet(SYS_INT_EVTOUT5, 2);
+    IntSystemEnable(SYS_INT_EVTOUT5);
+    HWREG(INTC_PHYS_BASE + PRU_INTC_EISR_REG) = PRU_I2C_PORT2_EVT;
+
+    IntRegister(SYS_INT_EVTOUT6, pbdrv_i2c_irq_2);
+    IntChannelSet(SYS_INT_EVTOUT6, 2);
+    IntSystemEnable(SYS_INT_EVTOUT6);
+    HWREG(INTC_PHYS_BASE + PRU_INTC_EISR_REG) = PRU_I2C_PORT3_EVT;
+
+    IntRegister(SYS_INT_EVTOUT7, pbdrv_i2c_irq_3);
+    IntChannelSet(SYS_INT_EVTOUT7, 2);
+    IntSystemEnable(SYS_INT_EVTOUT7);
+    HWREG(INTC_PHYS_BASE + PRU_INTC_EISR_REG) = PRU_I2C_PORT4_EVT;
+
+    pbio_busy_count_down();
+
+    PBIO_OS_ASYNC_END(PBIO_SUCCESS);
+}
+
 void pbdrv_i2c_init(void) {
     for (int i = 0; i < PBDRV_CONFIG_I2C_EV3_NUM_DEV; i++) {
         pbdrv_i2c_dev_t *i2c = &i2c_devs[i];
         i2c->pru_i2c_idx = i;
         i2c->is_initialized = true;
     }
+
+    pbio_busy_count_up();
+    pbio_os_process_start(&ev3_i2c_init_process, ev3_i2c_init_process_thread, NULL);
 }
 
 #endif // PBDRV_CONFIG_I2C_EV3