Merge pull request #334 from Remus7/master

Real Time Clock support and examples

examples/rtc_app/Makefile

@@ -0,0 +1,11 @@
+# Makefile for user application
+
+# Specify this directory relative to the current application.
+TOCK_USERLAND_BASE_DIR = ../../
+
+# Which files to compile.
+C_SRCS := $(wildcard *.c)
+
+# Include userland master makefile. Contains rules and flags for actually
+# building the application.
+include $(TOCK_USERLAND_BASE_DIR)/AppMakefile.mk

examples/rtc_app/main.c

@@ -0,0 +1,31 @@
+#include <rtc.h>
+#include <stdio.h>
+#include <timer.h>
+
+int main(void){
+  // Initialises a date struct with a certain timestamp
+  struct Date date = {
+    .year  = 2023,
+    .month = JANUARY,
+    .day   = 1,
+
+    .day_of_week = MONDAY,
+    .hour        = 12,
+    .minute      = 30,
+    .seconds     = 1
+  };
+
+  set_date(&date);
+  // Clock has a small delay before starting to count seconds
+  delay_ms(2000);
+
+  while (1) {
+    get_date(&date);
+    printf("Date: {year: %d, month: %d, day: %d, day_of_week: %d, hour: %d, minute: %d, seconds: %d}\n\n", date.year,
+           date.month, date.day, date.day_of_week, date.hour, date.minute, date.seconds);
+
+    // This delay uses an underlying timer in the kernel
+    delay_ms(1000);
+  }
+  return 0;
+}

libtock/rtc.c

@@ -0,0 +1,48 @@
+#include "rtc.h"
+#include <stdio.h>
+#include <stdlib.h>
+
+int date, time;
+
+static void rtc_cb(int   status __attribute__ ((unused)),
+                   int   upcall1,
+                   int   upcall2,
+                   void* ud __attribute__ ((unused))){
+  date = upcall1;
+  time = upcall2;
+}
+
+int get_date(struct Date *put_date){
+  subscribe_return_t sub = subscribe(DRIVER_NUM_RTC, 0, rtc_cb, malloc(sizeof(struct DateTime)));
+  if (!sub.success) {
+    return tock_status_to_returncode(sub.status);
+  }
+
+  syscall_return_t rval = command(DRIVER_NUM_RTC, 1, 0, 0);
+  if (!(rval.type == 128)) {
+    printf("%d", rval.type);
+  }
+
+  struct Date date_result = {
+    .year  = date % (1 << 21) / (1 << 9),
+    .month = date % (1 << 9) / (1 << 5),
+    .day   = date % (1 << 5),
+
+    .day_of_week = time % (1 << 20) / (1 << 17),
+    .hour        = time % (1 << 17) / (1 << 12),
+    .minute      = time % (1 << 12) / (1 << 6),
+    .seconds     = time % (1 << 6)
+  };
+
+  *put_date = date_result;
+  return tock_command_return_novalue_to_returncode(rval);
+}
+
+int set_date(const struct Date *set_date){
+  date = set_date->year * (1 << 9) + set_date->month * (1 << 5) + set_date->day;
+  time = set_date->day_of_week *
+         (1 << 17) + set_date->hour * (1 << 12) + set_date->minute * (1 << 6) + set_date->seconds;
+
+  syscall_return_t rval = command(DRIVER_NUM_RTC, 2, date, time);
+  return tock_command_return_novalue_to_returncode(rval);
+}

libtock/rtc.h

@@ -0,0 +1,66 @@
+#pragma once
+
+#include "tock.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#define DRIVER_NUM_RTC 0x00090007
+
+#define JANUARY 1
+#define FEBRUARY 2
+#define MARCH 3
+#define APRIL 4
+#define MAY 5
+#define JUNE 6
+#define JULY 7
+#define AUGUST 8
+#define SEPTEMBER 9
+#define OCTOBER 10
+#define NOVEMBER 11
+#define DECEMBER 12
+
+#define SUNDAY 0
+#define MONDAY 1
+#define TUESDAY 2
+#define WENSDAY 3
+#define THURSDAY 4
+#define FRIDAY 5
+#define SATURDAY 6
+
+// Date structure to store date and time
+struct Date{
+  int year;
+  int month;
+  int day;
+  int day_of_week;
+  int hour;
+  int minute;
+  int seconds;
+};
+
+// DateTime codifies Date structure into two u32 (int) numbers
+//     date: first number (year, month, day_of_the_month):
+//            - last 5 bits store the day_of_the_month
+//            - previous 4 bits store the month
+//            - previous 12 bits store the year
+//     time: second number (day_of_the_week, hour, minute, seconds):
+//            - last 6 bits store the seconds
+//            - previous 6 store the minute
+//            - previous 5 store the hour
+//            - previous 3 store the day_of_the_week
+struct DateTime{
+  int date;
+  int time;
+};
+
+// Fetches current date from registers and writes it to get_date
+int get_date(struct Date *get_date);
+
+// Writes set_date into the registers
+int set_date(const struct Date *set_date);
+
+#ifdef __cplusplus
+}
+#endif