/**************************************************************************** * arch/arm/src/lpc31xx/lpc31_resetclks.c * * Copyright (C) 2009 Gregory Nutt. All rights reserved. * Author: Gregory Nutt * * 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 #include #include #include "lpc31_cgudrvr.h" /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ /**************************************************************************** * Private Data ****************************************************************************/ /**************************************************************************** * Public Data ****************************************************************************/ /**************************************************************************** * Private Functions ****************************************************************************/ /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: lpc31_resetclks * * Description: * Put all clocks into a known, initial state * ****************************************************************************/ void lpc31_resetclks(void) { uint32_t regaddr; uint32_t regval; int bcrndx; int esrndx; int i; /* Switch all domain reference clocks to FFAST */ for (i = 0; i < CGU_NDOMAINS; i++) { /* Switch reference clock in to FFAST */ lpc31_selectfreqin((enum lpc31_domainid_e)i, CGU_FS_FFAST); /* Check if the domain has a BCR */ bcrndx = lpc31_bcrndx((enum lpc31_domainid_e)i); if (bcrndx != BCRNDX_INVALID) { /* Yes.. disable all BCRs */ putreg32(0, LPC31_CGU_BCR(bcrndx)); } } /* Disable all clocks except those that are necessary */ for (i = CLKID_FIRST; i <= CLKID_LAST; i++) { /* Check if this clock has an ESR register */ esrndx = lpc31_esrndx((enum lpc31_clockid_e)i); if (esrndx != ESRNDX_INVALID) { /* Yes.. Clear the clocks ESR to deselect fractional divider */ putreg32(0, LPC31_CGU_ESR(esrndx)); } /* Enable external enabling for all possible clocks to conserve power */ lpc31_enableexten((enum lpc31_clockid_e)i); /* Set enable-out's for only the following clocks */ regaddr = LPC31_CGU_PCR(i); regval = getreg32(regaddr); if (i == (int)CLKID_ARM926BUSIFCLK || i == (int)CLKID_MPMCCFGCLK) { regval |= CGU_PCR_ENOUTEN; } else { regval &= ~CGU_PCR_ENOUTEN; } putreg32(regval, regaddr); /* Set/clear the RUN bit in the PCR regiser of all clocks, depending * upon if the clock is needed by the board logic or not */ (void)lpc31_defclk((enum lpc31_clockid_e)i); } /* Disable all fractional dividers */ for (i = 0; i < CGU_NFRACDIV; i++) { regaddr = LPC31_CGU_FDC(i); regval = getreg32(regaddr); regval &= ~CGU_FDC_RUN; putreg32(regval, regaddr); } }