/**************************************************************************** * arch/arm/src/lpc31xx/lpc31_setfreqin.c * * Copyright (C) 2009-2010 Gregory Nutt. All rights reserved. * Author: Gregory Nutt * * References: * - NXP UM10314 LPC3130/31 User manual Rev. 1.01 — 9 September 2009 * - NXP lpc313x.cdl.drivers.zip example driver code * * 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_selectfreqin * * Description: * Set the base frequency source selection for with a clock domain * ****************************************************************************/ void lpc31_selectfreqin(enum lpc31_domainid_e dmnid, uint32_t finsel) { uint32_t scraddr = LPC31_CGU_SCR(dmnid); uint32_t fs1addr = LPC31_CGU_FS1(dmnid); uint32_t fs2addr = LPC31_CGU_FS2(dmnid); uint32_t scrbits; /* Get the frequency selection from the switch configuration register (SCR) * for this domain. */ scrbits = getreg32(scraddr) & ~(CGU_SCR_ENF1|CGU_SCR_ENF2); /* If FS1 is currently enabled set the reference clock to FS2 and enable FS2 */ if ((getreg32(LPC31_CGU_SSR(dmnid)) & CGU_SSR_FS1STAT) != 0) { /* Check if the selected frequency, FS1, is same as requested */ if ((getreg32(fs1addr) & CGU_FS_MASK) != finsel) { /* No.. Set up FS2 */ putreg32(finsel, fs2addr); putreg32(scrbits | CGU_SCR_ENF2, scraddr); } } /* FS1 is not currently enabled, check if the selected frequency, FS2, * is same as requested */ else if ((getreg32(fs2addr) & CGU_FS_MASK) != finsel) { /* No.. Set up FS1 */ putreg32(finsel, fs1addr); putreg32(scrbits | CGU_SCR_ENF1, scraddr); } }