diff options
Diffstat (limited to 'bsps/arm/shared/clock/clock-nxp-lpc.c')
-rw-r--r-- | bsps/arm/shared/clock/clock-nxp-lpc.c | 136 |
1 files changed, 136 insertions, 0 deletions
diff --git a/bsps/arm/shared/clock/clock-nxp-lpc.c b/bsps/arm/shared/clock/clock-nxp-lpc.c new file mode 100644 index 0000000000..c551f75f68 --- /dev/null +++ b/bsps/arm/shared/clock/clock-nxp-lpc.c @@ -0,0 +1,136 @@ +/** + * @file + * + * @ingroup lpc_clock + * + * @brief Clock driver configuration. + */ + +/* + * Copyright (c) 2009-2015 embedded brains GmbH. All rights reserved. + * + * embedded brains GmbH + * Dornierstr. 4 + * 82178 Puchheim + * Germany + * <rtems@embedded-brains.de> + * + * The license and distribution terms for this file may be + * found in the file LICENSE in this distribution or at + * http://www.rtems.org/license/LICENSE. + */ + +#include <rtems.h> +#include <rtems/timecounter.h> + +#include <bsp/lpc-clock-config.h> +#include <bsp/lpc-timer.h> + +#ifdef ARM_MULTILIB_ARCH_V4 + +/* This is defined in ../../../shared/dev/clock/clockimpl.h */ +void Clock_isr(rtems_irq_hdl_param arg); + +static volatile lpc_timer *const lpc_clock = + (volatile lpc_timer *) LPC_CLOCK_TIMER_BASE; + +static volatile lpc_timer *const lpc_timecounter = + (volatile lpc_timer *) LPC_CLOCK_TIMECOUNTER_BASE; + +static struct timecounter lpc_clock_tc; + +static uint32_t lpc_clock_tc_get_timecount(struct timecounter *tc) +{ + return lpc_timecounter->tc; +} + +static void lpc_clock_at_tick(void) +{ + lpc_clock->ir = LPC_TIMER_IR_MR0; +} + +static void lpc_clock_handler_install(void) +{ + rtems_status_code sc = RTEMS_SUCCESSFUL; + + sc = rtems_interrupt_handler_install( + LPC_CLOCK_INTERRUPT, + "Clock", + RTEMS_INTERRUPT_UNIQUE, + (rtems_interrupt_handler) Clock_isr, + NULL + ); + if (sc != RTEMS_SUCCESSFUL) { + rtems_fatal_error_occurred(0xdeadbeef); + } +} + +static void lpc_clock_initialize(void) +{ + uint64_t interval = ((uint64_t) LPC_CLOCK_REFERENCE + * (uint64_t) rtems_configuration_get_microseconds_per_tick()) / 1000000; + + /* Enable module */ + LPC_CLOCK_MODULE_ENABLE(); + + /* Reset timer */ + lpc_clock->tcr = LPC_TIMER_TCR_RST; + + /* Clear interrupt flags */ + lpc_clock->ir = LPC_TIMER_IR_ALL; + + /* Set timer mode */ + lpc_clock->ccr = 0; + + /* Timer is incremented every PERIPH_CLK tick */ + lpc_clock->pr = 0; + + /* Set match registers */ + lpc_clock->mr0 = (uint32_t) interval; + + /* Generate interrupt and reset counter on match with MR0 */ + lpc_clock->mcr = LPC_TIMER_MCR_MR0_INTR | LPC_TIMER_MCR_MR0_RST; + + /* No external match */ + lpc_clock->emr = 0x0; + + /* Enable timer */ + lpc_clock->tcr = LPC_TIMER_TCR_EN; + + /* Install timecounter */ + lpc_clock_tc.tc_get_timecount = lpc_clock_tc_get_timecount; + lpc_clock_tc.tc_counter_mask = 0xffffffff; + lpc_clock_tc.tc_frequency = LPC_CLOCK_REFERENCE; + lpc_clock_tc.tc_quality = RTEMS_TIMECOUNTER_QUALITY_CLOCK_DRIVER; + rtems_timecounter_install(&lpc_clock_tc); +} + +static void lpc_clock_cleanup(void) +{ + rtems_status_code sc = RTEMS_SUCCESSFUL; + + /* Disable timer */ + lpc_clock->tcr = 0x0; + + /* Remove interrupt handler */ + sc = rtems_interrupt_handler_remove( + LPC_CLOCK_INTERRUPT, + (rtems_interrupt_handler) Clock_isr, + NULL + ); + if (sc != RTEMS_SUCCESSFUL) { + rtems_fatal_error_occurred(0xdeadbeef); + } +} + +#define Clock_driver_support_at_tick() lpc_clock_at_tick() +#define Clock_driver_support_initialize_hardware() lpc_clock_initialize() +#define Clock_driver_support_install_isr(isr) \ + lpc_clock_handler_install() + +#define Clock_driver_support_shutdown_hardware() lpc_clock_cleanup() + +/* Include shared source clock driver code */ +#include "../../../shared/dev/clock/clockimpl.h" + +#endif /* ARM_MULTILIB_ARCH_V4 */ |