osd-contiki/cpu/cc26xx/dev/oscillators.c
2015-05-15 23:36:54 +01:00

172 lines
6.5 KiB
C

/*
* Copyright (c) 2015, Texas Instruments Incorporated - http://www.ti.com/
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the copyright holder nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
* OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*---------------------------------------------------------------------------*/
/**
* \addtogroup cc26xx-oscillators
* @{
*
* \file
* Implementation of CC26xxware oscillator control wrappers.
*/
/*---------------------------------------------------------------------------*/
#include "ti-lib.h"
#include <stdint.h>
/*---------------------------------------------------------------------------*/
static uint32_t
osc_interface_en(void)
{
uint32_t smph_clk_state;
/* Enable OSC DIG interface to change clock sources */
ti_lib_osc_interface_enable();
/* Save the state of the SMPH clock within AUX */
smph_clk_state = ti_lib_aux_wuc_clock_status(AUX_WUC_SMPH_CLOCK);
/* Make sure the SMPH clock within AUX is enabled */
ti_lib_aux_wuc_clock_enable(AUX_WUC_SMPH_CLOCK);
while(ti_lib_aux_wuc_clock_status(AUX_WUC_SMPH_CLOCK) != AUX_WUC_CLOCK_READY);
return smph_clk_state;
}
/*---------------------------------------------------------------------------*/
static void
osc_interface_dis(uint32_t smph_clk_state)
{
/* If the SMPH clock was off, turn it back off */
if(smph_clk_state == AUX_WUC_CLOCK_OFF) {
ti_lib_aux_wuc_clock_disable(AUX_WUC_SMPH_CLOCK);
}
/* Disable OSC DIG interface */
ti_lib_osc_interface_disable();
}
/*---------------------------------------------------------------------------*/
void
oscillators_select_lf_xosc(void)
{
/* Enable the Osc interface and remember the state of the SMPH clock */
uint32_t smph_clk_state = osc_interface_en();
/* Switch LF clock source to the LF XOSC if required */
if(ti_lib_osc_clock_source_get(OSC_SRC_CLK_LF) != OSC_XOSC_LF) {
ti_lib_osc_clock_source_set(OSC_SRC_CLK_LF, OSC_XOSC_LF);
/* Wait for LF clock source to become XOSC_LF */
while(ti_lib_osc_clock_source_get(OSC_SRC_CLK_LF) != OSC_XOSC_LF);
/* Disable the LF clock qualifiers */
ti_lib_ddi_16_bit_field_write(AUX_DDI0_OSC_BASE, DDI_0_OSC_O_CTL0,
DDI_0_OSC_CTL0_BYPASS_XOSC_LF_CLK_QUAL_M |
DDI_0_OSC_CTL0_BYPASS_RCOSC_LF_CLK_QUAL_M,
DDI_0_OSC_CTL0_BYPASS_RCOSC_LF_CLK_QUAL_S,
0x3);
}
/* Restore the SMPH clock and disable the OSC interface */
osc_interface_dis(smph_clk_state);
}
/*---------------------------------------------------------------------------*/
void
oscillators_select_lf_rcosc(void)
{
/* Enable the Osc interface and remember the state of the SMPH clock */
uint32_t smph_clk_state = osc_interface_en();
/* Switch LF clock source to the LF XOSC if required */
if(ti_lib_osc_clock_source_get(OSC_SRC_CLK_LF) != OSC_RCOSC_LF) {
ti_lib_osc_clock_source_set(OSC_SRC_CLK_LF, OSC_RCOSC_LF);
/* Wait for LF clock source to become XOSC_LF */
while(ti_lib_osc_clock_source_get(OSC_SRC_CLK_LF) != OSC_RCOSC_LF);
}
/* Restore the SMPH clock and disable the OSC interface */
osc_interface_dis(smph_clk_state);
}
/*---------------------------------------------------------------------------*/
void
oscillators_request_hf_xosc(void)
{
/* Enable the Osc interface and remember the state of the SMPH clock */
uint32_t smph_clk_state = osc_interface_en();
if(ti_lib_osc_clock_source_get(OSC_SRC_CLK_HF) != OSC_XOSC_HF) {
/*
* Request to switch to the crystal to enable radio operation. It takes a
* while for the XTAL to be ready so instead of performing the actual
* switch, we return and we do other stuff while the XOSC is getting ready.
*/
ti_lib_osc_clock_source_set(OSC_SRC_CLK_MF | OSC_SRC_CLK_HF, OSC_XOSC_HF);
}
/* Restore the SMPH clock and disable the OSC interface */
osc_interface_dis(smph_clk_state);
}
/*---------------------------------------------------------------------------*/
void
oscillators_switch_to_hf_xosc(void)
{
/* Enable the Osc interface and remember the state of the SMPH clock */
uint32_t smph_clk_state = osc_interface_en();
if(ti_lib_osc_clock_source_get(OSC_SRC_CLK_HF) != OSC_XOSC_HF) {
/* Switch the HF clock source (cc26xxware executes this from ROM) */
ti_lib_osc_hf_source_switch();
}
/* Restore the SMPH clock and disable the OSC interface */
osc_interface_dis(smph_clk_state);
}
/*---------------------------------------------------------------------------*/
void
oscillators_switch_to_hf_rc(void)
{
/* Enable the Osc interface and remember the state of the SMPH clock */
uint32_t smph_clk_state = osc_interface_en();
/* Set all clock sources to the HF RC Osc */
ti_lib_osc_clock_source_set(OSC_SRC_CLK_MF | OSC_SRC_CLK_HF, OSC_RCOSC_HF);
/* Check to not enable HF RC oscillator if already enabled */
if(ti_lib_osc_clock_source_get(OSC_SRC_CLK_HF) != OSC_RCOSC_HF) {
/* Switch the HF clock source (cc26xxware executes this from ROM) */
ti_lib_osc_hf_source_switch();
}
/* Restore the SMPH clock and disable the OSC interface */
osc_interface_dis(smph_clk_state);
}
/*---------------------------------------------------------------------------*/
/**
* @}
* @}
*/