/****************************************************************************
* arch/arm/src/lpc2378/lpc23xx_irq.c
*
* Copyright (C) 2010 Rommel Marcelo. All rights reserved.
* Author: Rommel Marcelo
*
* This file is part of the NuttX RTOS:
*
* Copyright (C) 2010 Gregory Nutt. 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 NuttX 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 OWNER 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.
*
****************************************************************************/
/* This file holds the NuttX start logic that runs when the LPC2378
* is reset. This logic must be located at address 0x0000:0000 in
* flash but may be linked to run at different locations based on
* the selected mode:
*
* default: Executes from 0x0000:0000. In non-default modes, the
* MEMAP register is set override the settings of the CPU configuration
* pins.
*
* CONFIG_EXTMEM_MODE: Code executes from external memory starting at
* address 0x8000:0000.
*
* CONFIG_RAM_MODE: Code executes from on-chip RAM at address
* 0x4000:0000.
*
* Starupt Code must be linked to run at the correct address
* corresponding to the selected mode.
*/
/***********************************************************************
* Included Files
**********************************************************************/
#include <nuttx/config.h>
#include <arch/board/board.h>
#include <sys/types.h>
#include "arm.h"
#include "up_arch.h"
#include "internal.h"
#include "lpc23xx_pinsel.h"
#include "lpc23xx_scb.h"
extern void IO_Init(void);
/***********************************************************************
* Definitions
**********************************************************************/
#if ((FOSC < 32000) || (FOSC > 50000000))
# error Fosc out of range (32KHz-50MHz)
# error correct and recompile
#endif
#if ((CCLK < 10000000) || (CCLK > 72000000))
# error cclk out of range (10MHz-72MHz)
# error correct PLL MULTIPLIER and recompile
#endif
#if ((FCCO < 275000000) || (FCCO > 550000000))
# error Fcco out of range (275MHz-550MHz)
# error internal algorithm error
#endif
/* Phase Locked Loop (PLL) initialization values
*
* Bit 0:14 MSEL: PLL Multiplier "M" Value
* CCLK = 57 600 000 Hz
* Bit 16:23 NSEL: PLL Divider "N" Value
* Fcco = (2 * M * F_in) / N
* 275MHz <= Fcco <= 550MHz
*
* PLL clock sources:
* Internal RC 0 default on reset
* Main Oscillator 1
* RTC 2
*/
#ifdef CONFIG_PLL_CLKSRC
# if ( (CONFIG_PLL_CLKSRC < 0) || (CONFIG_PLL_CLKSRC > 2) )
# error "PLL clock source not valid, check configuration "
# endif
#else
# error "PLL clock source not defined, check configuration file"
#endif
/* PLL provides CCLK and must always be configured */
#define PLL ( PLL_M | (PLL_N << 16) )
/* Memory Accelerator Module (MAM) initialization values
*
* MAM Control Register
* Bit 0:1 Mode
* 0 = Disabled
* 1 = Partially Enabled
* 2 = Fully Enabled
* MAM Timing Register
* Bit 0:2 Fetch Cycles
* 0 = Reserved
* 1 = 1 CCLK
* 2 = 2 CCLK
* 3 = 3 CCLK
* 4 = 4 CCLK
* 5 = 5 CCLK
* 6 = 6 CCLK
* 7 = 7 CCLK
*/
/* LPC2378 Rev. '-' errata MAM may not work if fully enabled */
#ifdef CONFIG_MAM_SETUP
# ifndef CONFIG_MAMCR_VALUE /* Can be selected from config file */
# define CONFIG_MAMCR_VALUE (MAMCR_PART)
# endif
# ifndef CONFIG_MAMTIM_VALUE /* Can be selected from config file */
# define CONFIG_MAMTIM_VALUE (0x00000003)
# endif
#endif
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: up_scbpllfeed
****************************************************************************/
static inline void up_scbpllfeed(void)
{
SCB_PLLFEED = 0xAA;
SCB_PLLFEED = 0x55;
}
/****************************************************************************
* Name: ConfigurePLL
****************************************************************************/
void ConfigurePLL(void)
{
uint32_t MSel, NSel;
/* LPC2378 Rev.'-' errata Enable the Ethernet block to enable 16k EnetRAM */
SCB_PCONP |= PCENET;
/* Vectors are remapped to Flash */
SCB_MEMMAP = MEMMAP2FLASH;
/* Enable PLL, disconnected */
if (SCB_PLLSTAT & (1 << 25))
{
SCB_PLLCON = 0x01;
up_scbpllfeed();
}
/* Disable PLL, disconnected */
SCB_PLLCON = 0;
up_scbpllfeed();
/* Enable main OSC */
SCB_SCS |= 0x20;
/* Wait until main OSC is usable */
while (!(SCB_SCS & 0x40));
/* select main OSC, 12MHz, as the PLL clock source */
SCB_CLKSRCSEL = CONFIG_PLL_CLKSRC;
/* Reconfigure PLL */
SCB_PLLCFG = PLL;
up_scbpllfeed();
/* Enable PLL */
SCB_PLLCON = 0x01;
up_scbpllfeed();
/* Set clock divider */
SCB_CCLKCFG = CCLK_DIV;
#ifdef CONFIG_USBDEV
/* usbclk = 288 MHz/6 = 48 MHz */
SCB_USBCLKCFG = USBCLK_DIV;
/* Turn On USB PCLK */
SCB_PCONP |= PCUSB;
#endif
/* Wait for PLL to lock */
while ((SCB_PLLSTAT & (1 << 26)) == 0);
MSel = SCB_PLLSTAT & 0x00007FFF;
NSel = (SCB_PLLSTAT & 0x00FF0000) >> 16;
while ((MSel != PLL_M) && (NSel != PLL_N));
/* Enable and connect */
SCB_PLLCON = 0x03;
up_scbpllfeed();
/* Check connect bit status */
while ((SCB_PLLSTAT & (1 << 25)) == 0);
/* Set memory accelerater module */
SCB_MAMCR = 0;
SCB_MAMTIM = CONFIG_MAMTIM_VALUE;
SCB_MAMCR = CONFIG_MAMCR_VALUE;
/* Enable FastIO on P0:P1 */
SCB_SCS |= 0x01;
IO_Init();
return;
}
