Diff: targets/TARGET_NUVOTON/TARGET_M480/pwmout_api.c

Revision:

172:7d866c31b3c5

diff -r 89b338f31ef1 -r 7d866c31b3c5 targets/TARGET_NUVOTON/TARGET_M480/pwmout_api.c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/targets/TARGET_NUVOTON/TARGET_M480/pwmout_api.c	Thu Aug 31 17:27:04 2017 +0100
@@ -0,0 +1,214 @@
+/* mbed Microcontroller Library
+ * Copyright (c) 2015-2016 Nuvoton
+ *
+ * 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 "pwmout_api.h"
+
+#if DEVICE_PWMOUT
+
+#include "cmsis.h"
+#include "pinmap.h"
+#include "PeripheralPins.h"
+#include "nu_modutil.h"
+#include "nu_miscutil.h"
+#include "nu_bitutil.h"
+
+struct nu_pwm_var {
+    uint32_t    en_msk;
+};
+
+static struct nu_pwm_var pwm0_var = {
+    .en_msk = 0
+};
+
+static struct nu_pwm_var pwm1_var = {
+    .en_msk = 0
+};
+
+static uint32_t pwm_modinit_mask = 0;
+
+static const struct nu_modinit_s pwm_modinit_tab[] = {
+    {PWM_0_0, EPWM0_MODULE, CLK_CLKSEL2_EPWM0SEL_PCLK0, 0, EPWM0_RST, EPWM0P0_IRQn, &pwm0_var},
+    {PWM_0_1, EPWM0_MODULE, CLK_CLKSEL2_EPWM0SEL_PCLK0, 0, EPWM0_RST, EPWM0P0_IRQn, &pwm0_var},
+    {PWM_0_2, EPWM0_MODULE, CLK_CLKSEL2_EPWM0SEL_PCLK0, 0, EPWM0_RST, EPWM0P1_IRQn, &pwm0_var},
+    {PWM_0_3, EPWM0_MODULE, CLK_CLKSEL2_EPWM0SEL_PCLK0, 0, EPWM0_RST, EPWM0P1_IRQn, &pwm0_var},
+    {PWM_0_4, EPWM0_MODULE, CLK_CLKSEL2_EPWM0SEL_PCLK0, 0, EPWM0_RST, EPWM0P2_IRQn, &pwm0_var},
+    {PWM_0_5, EPWM0_MODULE, CLK_CLKSEL2_EPWM0SEL_PCLK0, 0, EPWM0_RST, EPWM0P2_IRQn, &pwm0_var},
+
+    {PWM_1_0, EPWM1_MODULE, CLK_CLKSEL2_EPWM1SEL_PCLK1, 0, EPWM1_RST, EPWM1P0_IRQn, &pwm1_var},
+    {PWM_1_1, EPWM1_MODULE, CLK_CLKSEL2_EPWM1SEL_PCLK1, 0, EPWM1_RST, EPWM1P0_IRQn, &pwm1_var},
+    {PWM_1_2, EPWM1_MODULE, CLK_CLKSEL2_EPWM1SEL_PCLK1, 0, EPWM1_RST, EPWM1P1_IRQn, &pwm1_var},
+    {PWM_1_3, EPWM1_MODULE, CLK_CLKSEL2_EPWM1SEL_PCLK1, 0, EPWM1_RST, EPWM1P1_IRQn, &pwm1_var},
+    {PWM_1_4, EPWM1_MODULE, CLK_CLKSEL2_EPWM1SEL_PCLK1, 0, EPWM1_RST, EPWM1P2_IRQn, &pwm1_var},
+    {PWM_1_5, EPWM1_MODULE, CLK_CLKSEL2_EPWM1SEL_PCLK1, 0, EPWM1_RST, EPWM1P2_IRQn, &pwm1_var},
+
+    {NC, 0, 0, 0, 0, (IRQn_Type) 0, NULL}
+};
+
+static void pwmout_config(pwmout_t* obj, int start);
+
+void pwmout_init(pwmout_t* obj, PinName pin)
+{
+    obj->pwm = (PWMName) pinmap_peripheral(pin, PinMap_PWM);
+    MBED_ASSERT((int) obj->pwm != NC);
+
+    const struct nu_modinit_s *modinit = get_modinit(obj->pwm, pwm_modinit_tab);
+    MBED_ASSERT(modinit != NULL);
+    MBED_ASSERT(modinit->modname == (int) obj->pwm);
+
+    // NOTE: All channels (identified by PWMName) share a PWM module. This reset will also affect other channels of the same PWM module.
+    if (! ((struct nu_pwm_var *) modinit->var)->en_msk) {
+        // Reset this module if no channel enabled
+        SYS_ResetModule(modinit->rsetidx);
+    }
+
+    uint32_t chn =  NU_MODSUBINDEX(obj->pwm);
+
+    // NOTE: Channels 0/1/2/3/4/5 share a clock source.
+    if ((((struct nu_pwm_var *) modinit->var)->en_msk & 0x3F) == 0) {
+        // Select clock source of paired channels
+        CLK_SetModuleClock(modinit->clkidx, modinit->clksrc, modinit->clkdiv);
+        // Enable clock of paired channels
+        CLK_EnableModuleClock(modinit->clkidx);
+    }
+
+    // Wire pinout
+    pinmap_pinout(pin, PinMap_PWM);
+
+    // Default: period = 10 ms, pulse width = 0 ms
+    obj->period_us = 1000 * 10;
+    obj->pulsewidth_us = 0;
+    pwmout_config(obj, 0);
+
+    ((struct nu_pwm_var *) modinit->var)->en_msk |= 1 << chn;
+
+    // Mark this module to be inited.
+    int i = modinit - pwm_modinit_tab;
+    pwm_modinit_mask |= 1 << i;
+}
+
+void pwmout_free(pwmout_t* obj)
+{
+    EPWM_T *pwm_base = (EPWM_T *) NU_MODBASE(obj->pwm);
+    uint32_t chn =  NU_MODSUBINDEX(obj->pwm);
+    EPWM_ForceStop(pwm_base, 1 << chn);
+
+    const struct nu_modinit_s *modinit = get_modinit(obj->pwm, pwm_modinit_tab);
+    MBED_ASSERT(modinit != NULL);
+    MBED_ASSERT(modinit->modname == (int) obj->pwm);
+    ((struct nu_pwm_var *) modinit->var)->en_msk &= ~(1 << chn);
+
+
+    if ((((struct nu_pwm_var *) modinit->var)->en_msk & 0x3F) == 0) {
+        CLK_DisableModuleClock(modinit->clkidx);
+    }
+
+    // Mark this module to be deinited.
+    int i = modinit - pwm_modinit_tab;
+    pwm_modinit_mask &= ~(1 << i);
+}
+
+void pwmout_write(pwmout_t* obj, float value)
+{
+    obj->pulsewidth_us = NU_CLAMP((uint32_t) (value * obj->period_us), 0, obj->period_us);
+    pwmout_config(obj, 1);
+}
+
+float pwmout_read(pwmout_t* obj)
+{
+    return NU_CLAMP((((float) obj->pulsewidth_us) / obj->period_us), 0.0f, 1.0f);
+}
+
+void pwmout_period(pwmout_t* obj, float seconds)
+{
+    pwmout_period_us(obj, seconds * 1000000.0f);
+}
+
+void pwmout_period_ms(pwmout_t* obj, int ms)
+{
+    pwmout_period_us(obj, ms * 1000);
+}
+
+// Set the PWM period, keeping the duty cycle the same.
+void pwmout_period_us(pwmout_t* obj, int us)
+{
+    uint32_t period_us_old = obj->period_us;
+    uint32_t pulsewidth_us_old = obj->pulsewidth_us;
+    obj->period_us = us;
+    obj->pulsewidth_us = NU_CLAMP(obj->period_us * pulsewidth_us_old / period_us_old, 0, obj->period_us);
+    pwmout_config(obj, 1);
+}
+
+void pwmout_pulsewidth(pwmout_t* obj, float seconds)
+{
+    pwmout_pulsewidth_us(obj, seconds * 1000000.0f);
+}
+
+void pwmout_pulsewidth_ms(pwmout_t* obj, int ms)
+{
+    pwmout_pulsewidth_us(obj, ms * 1000);
+}
+
+void pwmout_pulsewidth_us(pwmout_t* obj, int us)
+{
+    obj->pulsewidth_us = NU_CLAMP(us, 0, obj->period_us);
+    pwmout_config(obj, 1);
+}
+
+int pwmout_allow_powerdown(void)
+{
+    uint32_t modinit_mask = pwm_modinit_mask;
+    while (modinit_mask) {
+        int pwm_idx = nu_ctz(modinit_mask);
+        const struct nu_modinit_s *modinit = pwm_modinit_tab + pwm_idx;
+        if (modinit->modname != NC) {
+            EPWM_T *pwm_base = (EPWM_T *) NU_MODBASE(modinit->modname);
+            uint32_t chn = NU_MODSUBINDEX(modinit->modname);
+            // Disallow entering power-down mode if PWM counter is enabled.
+            if ((pwm_base->CNTEN & (1 << chn)) && pwm_base->CMPDAT[chn]) {
+                return 0;
+            }
+        }
+        modinit_mask &= ~(1 << pwm_idx);
+    }
+
+    return 1;
+}
+
+static void pwmout_config(pwmout_t* obj, int start)
+{
+    EPWM_T *pwm_base = (EPWM_T *) NU_MODBASE(obj->pwm);
+    uint32_t chn = NU_MODSUBINDEX(obj->pwm);
+
+    // To avoid abnormal pulse on (re-)configuration, follow the sequence: stop/configure(/re-start).
+    // NOTE: The issue is met in ARM mbed CI test tests-api-pwm on M487.
+    EPWM_ForceStop(pwm_base, 1 << chn);
+
+    // NOTE: Support period < 1s
+    // NOTE: ARM mbed CI test fails due to first PWM pulse error. Workaround by:
+    //       1. Inverse duty cycle (100 - duty)
+    //       2. Inverse PWM output polarity
+    //       This trick is here to pass ARM mbed CI test. First PWM pulse error still remains.
+    EPWM_ConfigOutputChannel2(pwm_base, chn, 1000 * 1000, 100 - obj->pulsewidth_us * 100 / obj->period_us, obj->period_us);
+    pwm_base->POLCTL |= 1 << (EPWM_POLCTL_PINV0_Pos + chn);
+
+    if (start) {
+        // Enable output of the specified PWM channel
+        EPWM_EnableOutput(pwm_base, 1 << chn);
+        EPWM_Start(pwm_base, 1 << chn);
+    }
+}
+
+#endif