src/bsp/lk/platform/lpc15xx/init.c

/*
 * Copyright (c) 2014 Travis Geiselbrecht
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files
 * (the "Software"), to deal in the Software without restriction,
 * including without limitation the rights to use, copy, modify, merge,
 * publish, distribute, sublicense, and/or sell copies of the Software,
 * and to permit persons to whom the Software is furnished to do so,
 * subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
 * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
 * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

#include <err.h>
#include <stdio.h>
#include <debug.h>
#include <platform.h>
#include <platform/lpc.h>
#include <arch/arm/cm.h>

void lpc_debug_early_init(void);
void lpc_debug_init(void);

void lpc_gpio_early_init(void);
void lpc_gpio_init(void);

void lpc_usbc_early_init(void);
void lpc_usbc_init(void);

void platform_early_init(void)
{
    /* set up clocking for a board with an external oscillator */
    Chip_SetupXtalClocking();

    /* Set USB PLL input to main oscillator */
    Chip_Clock_SetUSBPLLSource(SYSCTL_PLLCLKSRC_MAINOSC);
    /* Setup USB PLL  (FCLKIN = 12MHz) * 4 = 48MHz
       MSEL = 3 (this is pre-decremented), PSEL = 1 (for P = 2)
       FCLKOUT = FCLKIN * (MSEL + 1) = 12MHz * 4 = 48MHz
       FCCO = FCLKOUT * 2 * P = 48MHz * 2 * 2 = 192MHz (within FCCO range) */
    Chip_Clock_SetupUSBPLL(3, 1);

    /* Powerup USB PLL */
    Chip_SYSCTL_PowerUp(SYSCTL_POWERDOWN_USBPLL_PD);

    /* Wait for PLL to lock */
    while (!Chip_Clock_IsUSBPLLLocked()) {}

    /* Set default system tick divder to 1 */
    Chip_Clock_SetSysTickClockDiv(1);

    /* start the generic systick driver */
    arm_cm_systick_init(Chip_Clock_GetMainClockRate());

    lpc_debug_early_init();
}

void platform_init(void)
{
    lpc_debug_init();
}

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