Merge pull request #6852 from mprse/issue_5308_fix

Fix for issue #5308 - RTC set/get time issue on NCS36510

Author: Cruz Monrreal

TESTS/mbed_drivers/rtc/main.cpp

@@ -144,7 +144,7 @@ void test_attach_RTC_stub_funtions()
     TEST_ASSERT_EQUAL(false, rtc_init_called);
 
     /* Check if time has been successfully set and retrieved. */
-    TEST_ASSERT_EQUAL(CUSTOM_TIME_1, seconds);
+    TEST_ASSERT_UINT32_WITHIN(RTC_DELTA, CUSTOM_TIME_1, seconds);
 }
 
 /* This test verifies if attach_rtc provides availability to
@@ -183,7 +183,7 @@ void test_attach_RTC_org_funtions()
     TEST_ASSERT_EQUAL(false, rtc_init_called);
 
     /* Check if time has been successfully set and retrieved. */
-    TEST_ASSERT_EQUAL(CUSTOM_TIME_1, seconds);
+    TEST_ASSERT_UINT32_WITHIN(RTC_DELTA, CUSTOM_TIME_1, seconds);
 }
 
 /* This test verifies if time() function returns
@@ -430,7 +430,7 @@ void test_functional_set()
     set_time(timeValue);
 
     /* Get current time and verify that new value has been set. */
-    TEST_ASSERT_EQUAL(timeValue, time(NULL));
+    TEST_ASSERT_UINT32_WITHIN(1, timeValue, time(NULL));
 }
 
 /* This test verifies if RTC counts seconds.

targets/TARGET_ONSEMI/TARGET_NCS36510/rtc_api.c

@@ -39,6 +39,15 @@
 #include "rtc.h"
 #include "cmsis_nvic.h"
 
+#define US_PER_SEC 1000000
+
+static time_t m_time_base;
+
+static uint32_t rtc_seconds_get()
+{
+    return (uint32_t)((fRtcRead() / US_PER_SEC) & 0xFFFFFFFF);
+}
+
 /* See rtc_apc.h for description */
 
 void rtc_init(void)
@@ -61,13 +70,20 @@ int rtc_isenabled(void)
 /* See rtc_apc.h for description */
 time_t rtc_read(void)
 {
-    return (uint32_t)(fRtcRead() & 0xFFFFFFFF); /* TODO Truncating 64 bit value to 32 bit */
+    return m_time_base + rtc_seconds_get();
 }
 
 /* See rtc_apc.h for description */
 void rtc_write(time_t t)
 {
-    fRtcWrite(t);
+    uint32_t seconds;
+    do {
+        seconds = rtc_seconds_get();
+        m_time_base = t - seconds;
+    /* If the number of seconds indicated by the counter changed during the
+       update of the time base, just repeat the update, now using the new
+       number of seconds. */
+    } while (seconds != rtc_seconds_get());
 }
 
 #endif /* DEVICE_RTC */

targets/targets.json

@@ -3753,7 +3753,7 @@
         "post_binary_hook": {"function": "NCS36510TargetCode.ncs36510_addfib"},
         "macros": ["CM3", "CPU_NCS36510", "TARGET_NCS36510", "LOAD_ADDRESS=0x3000"],
         "supported_toolchains": ["GCC_ARM", "ARM", "IAR"],
-        "device_has": ["ANALOGIN", "SERIAL", "I2C", "INTERRUPTIN", "PORTIN", "PORTINOUT", "PORTOUT", "PWMOUT", "SERIAL", "SERIAL_FC", "SLEEP", "SPI", "LOWPOWERTIMER", "TRNG", "SPISLAVE"],
+        "device_has": ["ANALOGIN", "SERIAL", "I2C", "INTERRUPTIN", "PORTIN", "PORTINOUT", "PORTOUT", "PWMOUT", "SERIAL", "SERIAL_FC", "SLEEP", "SPI", "LOWPOWERTIMER", "TRNG", "SPISLAVE", "RTC"],
         "release_versions": ["2", "5"]
     },
     "NUMAKER_PFM_M453": {