feat: integrate gdb support over serial port for bare-metal debugging.

[lunaix-os.git] / lunaix-os / hal / rtc.c

diff --git a/lunaix-os/hal/rtc.c b/lunaix-os/hal/rtc.c
index 319ad65663eea4e2e946ed6cb3b80e4ad023850e..2ffe76b14e2b4bf6c41e4bdc63072b417feca3bc 100644 (file)
--- a/lunaix-os/hal/rtc.c
+++ b/lunaix-os/hal/rtc.c
@@ -1,4 +1,25 @@
+/**
+ * @file rtc.c
+ * @author Lunaixsky
+ * @brief RTC & CMOS abstraction. Reference: MC146818A & Intel Series 500 PCH datasheet
+ * @version 0.1
+ * @date 2022-03-07
+ * 
+ * @copyright Copyright (c) 2022
+ * 
+ */
 #include <hal/rtc.h>
+#include <klibc/string.h>
+
+void
+rtc_init() {
+    uint8_t regA = rtc_read_reg(RTC_REG_A | WITH_NMI_DISABLED);
+    regA = (regA & ~0x7f) | RTC_FREQUENCY_1024HZ | RTC_DIVIDER_33KHZ;
+    rtc_write_reg(RTC_REG_A | WITH_NMI_DISABLED, regA);
+
+    // Make sure the rtc timer is disabled by default
+    rtc_disable_timer();
+}
 
 uint8_t
 rtc_read_reg(uint8_t reg_selector)
@@ -7,41 +28,28 @@ rtc_read_reg(uint8_t reg_selector)
     return io_inb(RTC_TARGET_PORT);
 }
 
+void
+rtc_write_reg(uint8_t reg_selector, uint8_t val)
+{
+    io_outb(RTC_INDEX_PORT, reg_selector);
+    io_outb(RTC_TARGET_PORT, val);
+}
+
 uint8_t
 bcd2dec(uint8_t bcd)
 {
-    return (bcd >> 4) * 10 + (bcd & 0x0f);
+    return ((bcd & 0xF0) >> 1) + ((bcd & 0xF0) >> 3) + (bcd & 0xf);
 }
 
+
 void
-rtc_get_datetime(rtc_datetime* datetime)
-{
-    datetime->year = rtc_read_reg(RTC_REG_YRS);
-    datetime->month = rtc_read_reg(RTC_REG_MTH);
-    datetime->day = rtc_read_reg(RTC_REG_DAY);
-    datetime->weekday = rtc_read_reg(RTC_REG_WDY);
-    datetime->hour = rtc_read_reg(RTC_REG_HRS);
-    datetime->minute = rtc_read_reg(RTC_REG_MIN);
-    datetime->second = rtc_read_reg(RTC_REG_SEC);
-
-    uint8_t regbv = rtc_read_reg(RTC_REG_B);
-
-    // Convert from bcd to binary when needed
-    if (!RTC_BIN_ENCODED(regbv)) {
-        datetime->year = bcd2dec(datetime->year);
-        datetime->month = bcd2dec(datetime->month);
-        datetime->day = bcd2dec(datetime->day);
-        datetime->hour = bcd2dec(datetime->hour);
-        datetime->minute = bcd2dec(datetime->minute);
-        datetime->second = bcd2dec(datetime->second);
-    }
-
-
-    // To 24 hour format
-    if (!RTC_24HRS_ENCODED(regbv)) {
-        datetime->hour = (datetime->hour >> 7) ? (12 + datetime->hour & 0x80)
-                                               : (datetime->hour & 0x80);
-    }
-
-    datetime->year += RTC_CURRENT_CENTRY * 100;
+rtc_enable_timer() {
+    uint8_t regB = rtc_read_reg(RTC_REG_B | WITH_NMI_DISABLED);
+    rtc_write_reg(RTC_REG_B | WITH_NMI_DISABLED, regB | RTC_TIMER_ON);
+}
+
+void
+rtc_disable_timer() {
+    uint8_t regB = rtc_read_reg(RTC_REG_B | WITH_NMI_DISABLED);
+    rtc_write_reg(RTC_REG_B | WITH_NMI_DISABLED, regB & ~RTC_TIMER_ON);
 }
\ No newline at end of file