tinySA/os/hal/platforms/LPC11xx/hal_lld.c

125 lines
4.8 KiB
C

/*
ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010,
2011 Giovanni Di Sirio.
This file is part of ChibiOS/RT.
ChibiOS/RT is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
ChibiOS/RT is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
/**
* @file LPC11xx/hal_lld.c
* @brief LPC11xx HAL subsystem low level driver source.
*
* @addtogroup HAL
* @{
*/
#include "ch.h"
#include "hal.h"
/**
* @brief Register missing in NXP header file.
*/
#define FLASHCFG (*((volatile uint32_t *)0x4003C010))
/*===========================================================================*/
/* Driver exported variables. */
/*===========================================================================*/
/*===========================================================================*/
/* Driver local variables. */
/*===========================================================================*/
/*===========================================================================*/
/* Driver local functions. */
/*===========================================================================*/
/*===========================================================================*/
/* Driver interrupt handlers. */
/*===========================================================================*/
/*===========================================================================*/
/* Driver exported functions. */
/*===========================================================================*/
/**
* @brief Low level HAL driver initialization.
*
* @notapi
*/
void hal_lld_init(void) {
/* SysTick initialization using the system clock.*/
nvicSetSystemHandlerPriority(HANDLER_SYSTICK, CORTEX_PRIORITY_SYSTICK);
SysTick->LOAD = LPC11xx_SYSCLK / CH_FREQUENCY - 1;
SysTick->VAL = 0;
SysTick->CTRL = SysTick_CTRL_CLKSOURCE_Msk |
SysTick_CTRL_ENABLE_Msk |
SysTick_CTRL_TICKINT_Msk;
}
/**
* @brief LPC11xx clocks and PLL initialization.
* @note All the involved constants come from the file @p board.h.
* @note This function must be invoked only after the system reset.
*
* @special
*/
void lpc111x_clock_init(void) {
unsigned i;
/* Flash wait states setting, the code takes care to not touch TBD bits.*/
FLASHCFG = (FLASHCFG & ~3) | LPC11xx_FLASHCFG_FLASHTIM;
/* System oscillator initialization if required.*/
#if LPC11xx_MAINCLK_SOURCE == SYSMAINCLKSEL_PLLOUT
#if LPC11xx_PLLCLK_SOURCE == SYSPLLCLKSEL_SYSOSC
LPC_SYSCON->SYSOSCCTRL = LPC11xx_SYSOSCCTRL;
LPC_SYSCON->PDRUNCFG &= ~(1 << 5); /* System oscillator ON. */
for (i = 0; i < 200; i++)
__NOP(); /* Stabilization delay. */
#endif /* LPC11xx_PLLCLK_SOURCE == SYSPLLCLKSEL_SYSOSC */
/* PLL initialization if required.*/
LPC_SYSCON->SYSPLLCLKSEL = LPC11xx_PLLCLK_SOURCE;
LPC_SYSCON->SYSPLLCLKUEN = 1; /* Really required? */
LPC_SYSCON->SYSPLLCLKUEN = 0;
LPC_SYSCON->SYSPLLCLKUEN = 1;
LPC_SYSCON->SYSPLLCTRL = LPC11xx_SYSPLLCTRL_MSEL | LPC11xx_SYSPLLCTRL_PSEL;
LPC_SYSCON->PDRUNCFG &= ~(1 << 7); /* System PLL ON. */
while ((LPC_SYSCON->SYSPLLSTAT & 1) == 0) /* Wait PLL lock. */
;
#endif /* LPC11xx_MAINCLK_SOURCE == SYSMAINCLKSEL_PLLOUT */
/* Main clock source selection.*/
LPC_SYSCON->MAINCLKSEL = LPC11xx_MAINCLK_SOURCE;
LPC_SYSCON->MAINCLKUEN = 1; /* Really required? */
LPC_SYSCON->MAINCLKUEN = 0;
LPC_SYSCON->MAINCLKUEN = 1;
while ((LPC_SYSCON->MAINCLKUEN & 1) == 0) /* Wait switch completion. */
;
/* ABH divider initialization, peripheral clocks are initially disabled,
the various device drivers will handle their own setup except GPIO and
IOCON that are left enabled.*/
LPC_SYSCON->SYSAHBCLKDIV = LPC11xx_SYSABHCLK_DIV;
LPC_SYSCON->SYSAHBCLKCTRL = 0x0001005F;
/* Memory remapping, vectors always in ROM.*/
LPC_SYSCON->SYSMEMREMAP = 2;
}
/** @} */