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author | Sebastian Huber <sebastian.huber@embedded-brains.de> | 2018-04-19 06:35:52 +0200 |
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committer | Sebastian Huber <sebastian.huber@embedded-brains.de> | 2018-04-20 09:57:01 +0200 |
commit | 7632906fc290b652416ab59eb5fb49356c064ed6 (patch) | |
tree | ac036b1f95637e044e10138ceea8d2b56d80ec97 /bsps/arm/raspberrypi | |
parent | bsps: Move bspsmpgetcurrentprocessor.c to bsps (diff) | |
download | rtems-7632906fc290b652416ab59eb5fb49356c064ed6.tar.bz2 |
bsps: Move clock drivers to bsps
This patch is a part of the BSP source reorganization.
Update #3285.
Diffstat (limited to 'bsps/arm/raspberrypi')
-rw-r--r-- | bsps/arm/raspberrypi/clock/clockdrv.c | 114 |
1 files changed, 114 insertions, 0 deletions
diff --git a/bsps/arm/raspberrypi/clock/clockdrv.c b/bsps/arm/raspberrypi/clock/clockdrv.c new file mode 100644 index 0000000000..2f6ec5b142 --- /dev/null +++ b/bsps/arm/raspberrypi/clock/clockdrv.c @@ -0,0 +1,114 @@ +/** + * @file + * + * @ingroup bsp_clock + * + * @brief Raspberry Pi clock support. + */ + +/* + * BCM2835 Clock driver + * + * Copyright (c) 2013 Alan Cudmore + * Copyright (c) 2016 Pavel Pisa + * + * 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 <bsp.h> +#include <bsp/irq.h> +#include <bsp/irq-generic.h> +#include <bsp/raspberrypi.h> +#include <rtems/timecounter.h> + +/* This is defined in ../../../shared/dev/clock/clockimpl.h */ +void Clock_isr(rtems_irq_hdl_param arg); + +static struct timecounter raspberrypi_tc; + +static uint32_t raspberrypi_clock_get_timecount(struct timecounter *tc) +{ + return BCM2835_REG(BCM2835_GPU_TIMER_CLO); +} + +static void raspberrypi_clock_at_tick(void) +{ + uint32_t act_val; + uint32_t next_cmp = BCM2835_REG(BCM2835_GPU_TIMER_C3); + next_cmp += rtems_configuration_get_microseconds_per_tick(); + BCM2835_REG(BCM2835_GPU_TIMER_C3) = next_cmp; + act_val = BCM2835_REG(BCM2835_GPU_TIMER_CLO); + + /* + * Clear interrupt only if there is time left to the next tick. + * If time of the next tick has already passed then interrupt + * request stays active and fires immediately after current tick + * processing is finished. + */ + if ((int32_t)(next_cmp - act_val) > 0) + BCM2835_REG(BCM2835_GPU_TIMER_CS) = BCM2835_GPU_TIMER_CS_M3; +} + +static void raspberrypi_clock_handler_install_isr( + rtems_isr_entry clock_isr +) +{ + rtems_status_code sc = RTEMS_SUCCESSFUL; + + if (clock_isr != NULL) { + sc = rtems_interrupt_handler_install( + BCM2835_IRQ_ID_GPU_TIMER_M3, + "Clock", + RTEMS_INTERRUPT_UNIQUE, + (rtems_interrupt_handler) clock_isr, + NULL + ); + } else { + /* Remove interrupt handler */ + sc = rtems_interrupt_handler_remove( + BCM2835_IRQ_ID_GPU_TIMER_M3, + (rtems_interrupt_handler) Clock_isr, + NULL + ); + } + if ( sc != RTEMS_SUCCESSFUL ) { + rtems_fatal_error_occurred(0xdeadbeef); + } +} + +static void raspberrypi_clock_initialize_hardware(void) +{ + uint32_t next_cmp = BCM2835_REG(BCM2835_GPU_TIMER_CLO); + next_cmp += rtems_configuration_get_microseconds_per_tick(); + BCM2835_REG(BCM2835_GPU_TIMER_C3) = next_cmp; + BCM2835_REG(BCM2835_GPU_TIMER_CS) = BCM2835_GPU_TIMER_CS_M3; + + raspberrypi_tc.tc_get_timecount = raspberrypi_clock_get_timecount; + raspberrypi_tc.tc_counter_mask = 0xffffffff; + raspberrypi_tc.tc_frequency = 1000000; /* 1 MHz */ + raspberrypi_tc.tc_quality = RTEMS_TIMECOUNTER_QUALITY_CLOCK_DRIVER; + rtems_timecounter_install(&raspberrypi_tc); +} + +static void raspberrypi_clock_cleanup(void) +{ + bsp_interrupt_vector_disable(BCM2835_IRQ_ID_GPU_TIMER_M3); +} + +#define Clock_driver_support_at_tick() raspberrypi_clock_at_tick() + +#define Clock_driver_support_initialize_hardware() raspberrypi_clock_initialize_hardware() + +#define Clock_driver_support_shutdown_hardware() raspberrypi_clock_cleanup() + +#define Clock_driver_support_install_isr(clock_isr) \ + raspberrypi_clock_handler_install_isr(clock_isr) + +#define CLOCK_DRIVER_USE_ONLY_BOOT_PROCESSOR 1 + +#include "../../../shared/dev/clock/clockimpl.h" |