Import Mbed OS hard-float snapshot

targets/TARGET_ARM_FM/TARGET_FVP_MPS2/us_ticker.c

@@ -0,0 +1,117 @@
+/* mbed Microcontroller Library
+ * Copyright (c) 2006-2019 ARM Limited
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#include <stddef.h>
+#include "us_ticker_api.h"
+#include "PeripheralNames.h"
+#define US_TICKER_COUNTER     CMSDK_DUALTIMER1
+#define US_TICKER_INTERRUPT   CMSDK_DUALTIMER2
+#define US_TICKER_TIMER_IRQn  DUALTIMER_IRQn
+
+/** mbed OS HAL API defined us_ticker as an increment ticker
+ *  MPS2 platform provided in SSE-200 are decrement tickers
+ *  with interrupt fired counter reaches 0.
+ *
+ *  So 2 Timers are used to construct mbed OS HAL ticker.
+ *
+ *  TIMER1 is for counting, and returns inverted binary when read from it
+ *  TIMER1 will be kept in free-running mode (default, and not generate interrupts)
+ *
+ *  TIMER2 is for generating interrupts
+ *  So TIMER2 is set to periodic mode, which start decrement counting form LOADVALUE generates interrupts at 0
+ *  and TIMER2 also set into one-shot mode, which counter halts when is reaches 0
+ */
+
+static int us_ticker_inited = 0;
+
+void us_ticker_init(void)
+{
+    if (us_ticker_inited) {
+        us_ticker_disable_interrupt();
+        return;
+    }
+
+    US_TICKER_COUNTER->TimerControl    = 0x0ul; // disable TIMER1 and reset all control
+    US_TICKER_INTERRUPT->TimerControl  = 0x0ul; // disable TIMER2 and reset all control
+
+    US_TICKER_COUNTER->TimerLoad       = 0xFFFFFFFFul;
+    US_TICKER_INTERRUPT->TimerLoad     = 0xFFFFFFFFul;
+
+    US_TICKER_COUNTER->TimerControl   |= CMSDK_DUALTIMER1_CTRL_SIZE_Msk; // set TIMER1 to 32 bit counter
+    US_TICKER_INTERRUPT->TimerControl |= CMSDK_DUALTIMER2_CTRL_SIZE_Msk; // set TIMER2 to 32 bit counter
+
+    US_TICKER_COUNTER->TimerControl   |= 0x1 << CMSDK_DUALTIMER1_CTRL_PRESCALE_Pos; // set TIMER1 with 4 stages prescale
+    US_TICKER_INTERRUPT->TimerControl |= 0x1 << CMSDK_DUALTIMER2_CTRL_PRESCALE_Pos; // set TIMER2 with 4 stages prescale
+
+    US_TICKER_INTERRUPT->TimerControl |= CMSDK_DUALTIMER2_CTRL_MODE_Msk;     // set TIMER2 periodic mode
+    US_TICKER_INTERRUPT->TimerControl |= CMSDK_DUALTIMER2_CTRL_ONESHOOT_Msk; // set TIMER2 one-shot mode
+
+    US_TICKER_COUNTER->TimerControl |= CMSDK_DUALTIMER1_CTRL_EN_Msk; // enable TIMER1 counter
+
+    NVIC_SetVector(US_TICKER_TIMER_IRQn, (uint32_t)us_ticker_irq_handler);
+    us_ticker_inited = 1;
+}
+
+void us_ticker_free(void)
+{
+    US_TICKER_COUNTER->TimerControl    &= ~CMSDK_DUALTIMER1_CTRL_EN_Msk; // disable TIMER1
+    US_TICKER_INTERRUPT->TimerControl  &= ~CMSDK_DUALTIMER2_CTRL_EN_Msk; // disable TIMER2
+    us_ticker_disable_interrupt();
+    us_ticker_inited = 0;
+}
+
+uint32_t us_ticker_read()
+{
+    return ~US_TICKER_COUNTER->TimerValue;
+}
+
+void us_ticker_set_interrupt(timestamp_t timestamp)
+{
+    uint32_t delta =  timestamp - us_ticker_read();
+    US_TICKER_INTERRUPT->TimerControl &= ~CMSDK_DUALTIMER2_CTRL_EN_Msk;   // disable TIMER2
+    US_TICKER_INTERRUPT->TimerLoad = delta;                               // Set TIMER2 load value
+    US_TICKER_INTERRUPT->TimerControl |= CMSDK_DUALTIMER2_CTRL_INTEN_Msk; // enable TIMER2 interrupt
+    US_TICKER_INTERRUPT->TimerControl |= CMSDK_DUALTIMER2_CTRL_EN_Msk;    // enable TIMER2 counter
+    NVIC_EnableIRQ(US_TICKER_TIMER_IRQn);
+}
+
+void us_ticker_fire_interrupt(void)
+{
+    NVIC_EnableIRQ(US_TICKER_TIMER_IRQn);
+    NVIC_SetPendingIRQ(US_TICKER_TIMER_IRQn);
+}
+
+
+void us_ticker_disable_interrupt(void)
+{
+    US_TICKER_INTERRUPT->TimerControl &= ~CMSDK_DUALTIMER2_CTRL_INTEN_Msk;
+    US_TICKER_INTERRUPT->TimerControl &= ~CMSDK_DUALTIMER2_CTRL_EN_Msk;  // disable TIMER2
+    NVIC_DisableIRQ(US_TICKER_TIMER_IRQn);
+}
+
+void us_ticker_clear_interrupt(void)
+{
+    US_TICKER_INTERRUPT->TimerIntClr = CMSDK_DUALTIMER2_INTCLR_Msk;
+}
+
+const ticker_info_t *us_ticker_get_info(void)
+{
+    static const ticker_info_t info = {
+        1562500,    // 4 stages prescaled from 25MHz (dived by 16)
+        32     // 32 bit counter
+    };
+    return &info;
+}