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| author | gdisirio <gdisirio@35acf78f-673a-0410-8e92-d51de3d6d3f4> | 2013-06-15 15:58:20 +0000 |
|---|---|---|
| committer | gdisirio <gdisirio@35acf78f-673a-0410-8e92-d51de3d6d3f4> | 2013-06-15 15:58:20 +0000 |
| commit | 7c68ef157d009f9932ac47ba21ba5d74e321623f (patch) | |
| tree | 6c2442ca44cd090656ec3059ffb959f3d747e18d /os/hal/platforms/LPC8xx/gpt_lld.c | |
| parent | 076746af63d317f8e96766b9137a65679f60463f (diff) | |
| parent | e0d850113610f3efa0c0ac4946901f683e5e7332 (diff) | |
| download | ChibiOS-7c68ef157d009f9932ac47ba21ba5d74e321623f.tar.gz ChibiOS-7c68ef157d009f9932ac47ba21ba5d74e321623f.tar.bz2 ChibiOS-7c68ef157d009f9932ac47ba21ba5d74e321623f.zip | |
git-svn-id: svn://svn.code.sf.net/p/chibios/svn/branches/kernel_3_dev@5854 35acf78f-673a-0410-8e92-d51de3d6d3f4
Diffstat (limited to 'os/hal/platforms/LPC8xx/gpt_lld.c')
| -rw-r--r-- | os/hal/platforms/LPC8xx/gpt_lld.c | 278 |
1 files changed, 278 insertions, 0 deletions
diff --git a/os/hal/platforms/LPC8xx/gpt_lld.c b/os/hal/platforms/LPC8xx/gpt_lld.c new file mode 100644 index 000000000..44601272b --- /dev/null +++ b/os/hal/platforms/LPC8xx/gpt_lld.c @@ -0,0 +1,278 @@ +/*
+ ChibiOS/RT - Copyright (C) 2006-2013 Giovanni Di Sirio
+
+ 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.
+*/
+
+/**
+ * @file LPC8xx/gpt_lld.c
+ * @brief LPC8xx GPT subsystem low level driver source.
+ *
+ * @addtogroup GPT
+ * @{
+ */
+
+#include "ch.h"
+#include "hal.h"
+
+#if HAL_USE_GPT || defined(__DOXYGEN__)
+
+/*===========================================================================*/
+/* Driver exported variables. */
+/*===========================================================================*/
+
+/**
+ * @brief GPT1 driver identifier.
+ * @note The driver GPT1 allocates MRT channel0 when enabled.
+ */
+#if LPC8xx_GPT_USE_MRT0 || defined(__DOXYGEN__)
+GPTDriver GPTD1;
+#endif
+
+/**
+ * @brief GPT2 driver identifier.
+ * @note The driver GPT1 allocates MRT channel1 when enabled.
+ */
+#if LPC8xx_GPT_USE_MRT1 || defined(__DOXYGEN__)
+GPTDriver GPTD2;
+#endif
+
+/**
+ * @brief GPT3 driver identifier.
+ * @note The driver GPT1 allocates MRT channel2 when enabled.
+ */
+#if LPC8xx_GPT_USE_MRT2 || defined(__DOXYGEN__)
+GPTDriver GPTD3;
+#endif
+
+/**
+ * @brief GPT4 driver identifier.
+ * @note The driver GPT1 allocates MRT channel3 when enabled.
+ */
+#if LPC8xx_GPT_USE_MRT3 || defined(__DOXYGEN__)
+GPTDriver GPTD4;
+#endif
+
+/*===========================================================================*/
+/* Driver local variables. */
+/*===========================================================================*/
+static uint32_t clk_enabled;
+
+/*===========================================================================*/
+/* Driver local functions. */
+/*===========================================================================*/
+/**
+ * @brief Shared IRQ handler.
+ *
+ * @param[in] gptp pointer to a @p GPTDriver object
+ * @param[in] irq_flag irq flag bit
+ */
+
+static void gpt_lld_serve_interrupt( GPTDriver *gptp ) {
+
+ if (gptp->tmr->STAT & 0x01) {
+ gptp->tmr->STAT |= 0x01;
+
+ if (gptp->state == GPT_ONESHOT) {
+ gptp->state = GPT_READY; /* Back in GPT_READY state. */
+ }
+ gptp->config->callback(gptp);
+ }
+ return;
+}
+
+/*===========================================================================*/
+/* Driver interrupt handlers. */
+/*===========================================================================*/
+
+/**
+
+ * @brief MRT IRQ handler.
+ *
+ */
+CH_IRQ_HANDLER(Vector68) {
+ CH_IRQ_PROLOGUE();
+
+#if LPC8xx_GPT_USE_MRT0
+ gpt_lld_serve_interrupt( &GPTD1 );
+#endif
+
+#if LPC8xx_GPT_USE_MRT1
+ gpt_lld_serve_interrupt( &GPTD2 );
+#endif
+
+#if LPC8xx_GPT_USE_MRT2
+ gpt_lld_serve_interrupt( &GPTD3 );
+#endif
+
+#if LPC8xx_GPT_USE_MRT3
+ gpt_lld_serve_interrupt( &GPTD4 );
+#endif
+
+ CH_IRQ_EPILOGUE();
+}
+
+/*===========================================================================*/
+/* Driver exported functions. */
+/*===========================================================================*/
+
+/**
+ * @brief Low level GPT driver initialization.
+ *
+ * @notapi
+ */
+void gpt_lld_init(void) {
+
+#if LPC8xx_GPT_USE_MRT0
+ GPTD1.tmr = &(LPC_MRT->Channel[0]);
+ gptObjectInit(&GPTD1);
+ GPTD1.mask = (1<<0);
+#endif
+
+#if LPC8xx_GPT_USE_MRT1
+ GPTD2.tmr = &(LPC_MRT->Channel[1]);
+ gptObjectInit(&GPTD2);
+ GPTD1.mask = (1<<1);
+#endif
+
+#if LPC8xx_GPT_USE_MRT2
+ GPTD3.tmr = &(LPC_MRT->Channel[2]);
+ gptObjectInit(&GPTD3);
+ GPTD1.mask = (1<<2);
+#endif
+
+#if LPC8xx_GPT_USE_MRT3
+ GPTD4.tmr = &(LPC_MRT->Channel[3]);
+ gptObjectInit(&GPTD4);
+ GPTD1.mask = (1<<3);
+#endif
+
+ clk_enabled = FALSE;
+ return;
+}
+
+/**
+ * @brief Configures and activates a GPT channel.
+ *
+ * @param[in] gptp pointer to the @p GPTDriver object
+ *
+ * @notapi
+ */
+void gpt_lld_start(GPTDriver *gptp) {
+
+ if( !clk_enabled ) {
+
+ /* Enable clock & reset MRT */
+ LPC_SYSCON->SYSAHBCLKCTRL |= (1<<10);
+ LPC_SYSCON->PRESETCTRL &= ~(1<<7);
+ LPC_SYSCON->PRESETCTRL |= (1<<7);
+
+ nvicEnableVector(MRT_IRQn,
+ CORTEX_PRIORITY_MASK(LPC8xx_GPT_MRT_IRQ_PRIORITY));
+
+ clk_enabled |= gptp->mask;
+ }
+
+ /* Prescaler value calculation.*/
+ gptp->pr = (LPC8xx_SYSCLK / gptp->config->frequency);
+ chDbgAssert((gptp->pr * gptp->config->frequency) == LPC8xx_SYSCLK,
+ "gpt_lld_start(), #1", "invalid frequency");
+
+ /* MRT Channel configuration.*/
+ gptp->tmr->CTRL = 0;
+ gptp->tmr->STAT |= 1;
+
+}
+
+/**
+ * @brief Deactivates a GPT channel.
+ *
+ * @param[in] gptp pointer to the @p GPTDriver object
+ *
+ * @notapi
+ */
+void gpt_lld_stop(GPTDriver *gptp) {
+
+ /* Shared peripheral -
+ mark this channel as disabled */
+ clk_enabled &= ~gptp->mask;
+
+ /* All channels disabled? */
+ if( !clk_enabled )
+ {
+ /* Disable periheral */
+ nvicDisableVector(MRT_IRQn);
+ LPC_SYSCON->SYSAHBCLKCTRL &= ~(1<<10);
+ }
+
+ return;
+}
+
+/**
+ * @brief Starts the timer in continuous/One shot mode.
+ *
+ * @param[in] gptp pointer to the @p GPTDriver object
+ * @param[in] interval period in ticks
+ *
+ * @notapi
+ */
+void gpt_lld_start_timer(GPTDriver *gptp, gptcnt_t interval) {
+
+ gptp->tmr->INTVAL = (1<<31)|((interval*gptp->pr) - 1);
+
+ if (gptp->state == GPT_ONESHOT)
+ gptp->tmr->CTRL = (1<<1)|1;
+ else
+ gptp->tmr->CTRL = 1;
+}
+
+/**
+ * @brief Stops the timer.
+ *
+ * @param[in] gptp pointer to the @p GPTDriver object
+ *
+ * @notapi
+ */
+void gpt_lld_stop_timer(GPTDriver *gptp) {
+
+ gptp->tmr->INTVAL = (1<<31);
+ gptp->tmr->CTRL = 0;
+ gptp->tmr->STAT |= 1;
+}
+
+/**
+ * @brief Starts the timer in one shot mode and waits for completion.
+ * @details This function specifically polls the timer waiting for completion
+ * in order to not have extra delays caused by interrupt servicing,
+ * this function is only recommended for short delays.
+ *
+ * @param[in] gptp pointer to the @p GPTDriver object
+ * @param[in] interval time interval in ticks
+ *
+ * @notapi
+ */
+void gpt_lld_polled_delay(GPTDriver *gptp, gptcnt_t interval) {
+
+ gptp->tmr->INTVAL = (1<<31)|((interval*gptp->pr) - 1);
+ gptp->tmr->CTRL = (1<<1);
+
+ while (gptp->tmr->STAT & (1<<1))
+ ;
+
+ gptp->tmr->CTRL = 0;
+ gptp->tmr->STAT |= 1;
+}
+
+#endif /* HAL_USE_GPT */
+
+/** @} */
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