/****************************************************************************
* arch/arm/src/nuc1xx/nuc_clockconfig.c
*
* Copyright (C) 2013 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* 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.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <stdint.h>
#include <assert.h>
#include <debug.h>
#include <nuttx/arch.h>
#include <arch/board/board.h>
#include "up_arch.h"
#include "chip.h"
#include "chip/chip/nuc_gcr.h"
#include "chip/chip/nuc_clk.h"
#include "nuc_clockconfig.h"
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: nuc_unlock
*
* Description:
* Unlock registers
*
* Input Parameters:
* None
*
* Returned Value:
* None
*
****************************************************************************/
static inline void nuc_unlock(void)
{
putreg32(0x59, NUC_GCR_REGWRPROT);
putreg32(0x16, NUC_GCR_REGWRPROT);
putreg32(0x88, NUC_GCR_REGWRPROT);
}
/****************************************************************************
* Name: nuclock
*
* Description:
* Lok registers
*
* Input Parameters:
* None
*
* Returned Value:
* None
*
****************************************************************************/
static inline void nuc_lock(void)
{
putreg32(0, NUC_GCR_REGWRPROT);
}
/****************************************************************************
* Public Functions
****************************************************************************/
/************************************************************************************
* Name: nuc_clockconfig
*
* Description:
* Called to establish the clock settings based on the values in board.h.
*
* Input Parameters:
* None
*
* Returned Value:
* None
*
************************************************************************************/
void nuc_clockconfig(void)
{
uint32_t regval;
/* Unlock registers */
nuc_unlock();
/* Enable External 4~24 mhz high speed crystal (And other clocks if needed by
* other drivers).
*/
regval = getreg32(NUC_CLK_PWRCON);
regval |= CLK_PWRCON_XTL12M_EN;
#ifdef CONFIG_NUC_XTALLO
regval |= CLK_PWRCON_XTL32K_EN;
#endif
#ifdef CONFIG_NUC_INTHI
regval |= CLK_PWRCON_OSC22M_EN;
#endif
putreg32(regval, NUC_CLK_PWRCON);
/* Delay to assure that crystal input to be stable */
up_mdelay(5);
/* Set up the PLL configuration.
*
* Feedback divider (FB_DV) = Determined by settings in board.h
* Input divider (IN_DV) = Determined by settings in board.h
* Output divider (OUT_DV) = Determined by settings in board.h
* Power down mode (PD) = Normal mode (0)
* Bypass (BP) = Normal mode (0)
* FOUT enable (OE) = PLL FOUT enabled (0)
* PLL srouce clock (PLL_SRC) = External high speed crystal (0)
*/
regval = getreg32(NUC_CLK_PLLCON);
regval &= ~(CLK_PLLCON_FB_DV_MASK | CLK_PLLCON_IN_DV_MASK |
CLK_PLLCON_OUT_DV_MASK | CLK_PLLCON_PD | CLK_PLLCON_BP |
CLK_PLLCON_OE | CLK_PLLCON_PLL_SRC);
regval |= (CLK_PLLCON_FB_DV(BOARD_PLL_FB_DV) |
CLK_PLLCON_IN_DV(BOARD_PLL_IN_DV) |
CLK_PLLCON_OUT_DV(BOARD_PLL_OUT_DV));
putreg32(regval, NUC_CLK_PLLCON);
/* Delay until the PLL output is stable */
up_mdelay(5);
/* Set the HCLK divider per settings from the board.h file */
regval = getreg32(NUC_CLK_CLKDIV);
regval &= ~CLK_CLKDIV_HCLK_N_MASK;
regval |= CLK_CLKDIV_HCLK_N(BOARD_HCLK_N);
putreg32(regval, NUC_CLK_CLKDIV);
/* Select the PLL output as the HCLKC source */
regval = getreg32(NUC_CLK_CLKSEL0);
regval &= ~CLK_CLKSEL0_HCLK_S_MASK;
regval |= CLK_CLKSEL0_HCLK_S_PLL;
putreg32(regval, NUC_CLK_CLKSEL0);
up_mdelay(1);
/* Lock the registers */
nuc_lock();
}
