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author | patacongo <patacongo@42af7a65-404d-4744-a932-0658087f49c3> | 2009-12-30 15:58:43 +0000 |
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committer | patacongo <patacongo@42af7a65-404d-4744-a932-0658087f49c3> | 2009-12-30 15:58:43 +0000 |
commit | ea7ba8d9a64cabb45a18375b1ded3b2df1361a7b (patch) | |
tree | 39d1817b9138332366d8dfb8c1849fbed1d14696 /nuttx/arch/arm/src | |
parent | faba0ca69b52e5ec805ea6584741af148df6ed8f (diff) | |
download | px4-nuttx-ea7ba8d9a64cabb45a18375b1ded3b2df1361a7b.tar.gz px4-nuttx-ea7ba8d9a64cabb45a18375b1ded3b2df1361a7b.tar.bz2 px4-nuttx-ea7ba8d9a64cabb45a18375b1ded3b2df1361a7b.zip |
Add clock reset logic
git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@2464 42af7a65-404d-4744-a932-0658087f49c3
Diffstat (limited to 'nuttx/arch/arm/src')
-rwxr-xr-x | nuttx/arch/arm/src/lpc313x/lpc313x_resetclks.c | 151 |
1 files changed, 151 insertions, 0 deletions
diff --git a/nuttx/arch/arm/src/lpc313x/lpc313x_resetclks.c b/nuttx/arch/arm/src/lpc313x/lpc313x_resetclks.c new file mode 100755 index 000000000..822e3a647 --- /dev/null +++ b/nuttx/arch/arm/src/lpc313x/lpc313x_resetclks.c @@ -0,0 +1,151 @@ +/**************************************************************************** + * arch/arm/src/lpc313x/lpc313x_resetclks.c + * + * Copyright (C) 2009 Gregory Nutt. All rights reserved. + * Author: Gregory Nutt <spudmonkey@racsa.co.cr> + * + * 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 <arch/board/board.h> + +#include "lpc313x_cgudrvr.h" + +/**************************************************************************** + * Pre-processor Definitions + ****************************************************************************/ + +/**************************************************************************** + * Private Data + ****************************************************************************/ + +/**************************************************************************** + * Public Data + ****************************************************************************/ + +/**************************************************************************** + * Private Functions + ****************************************************************************/ + +/**************************************************************************** + * Public Functions + ****************************************************************************/ + +/**************************************************************************** + * Name: lpc313x_resetclks + * + * Description: + * Put all clocks into a known, initial state + * + ****************************************************************************/ + +void lpc313x_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 */ + + lpc313x_selectfreqin((enum lpc313x_domainid_e)i, CGU_FS_FFAST); + + /* Check if the domain has a BCR */ + + bcrndx = lp313x_bcrndx((enum lpc313x_domainid_e)i); + if (bcrndx != BCRNDX_INVALID) + { + /* Yes.. isable all BCRs */ + + putreg32(0, LPC313X_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 = lp313x_esrndx((enum lpc313x_clockid_e)i); + if (esrndx != ESRNDX_INVALID) + { + /* Yes.. Clear the clocks ESR to deselect fractional divider */ + + putreg32(0, LPC313X_CGU_ESR(esrndx)); + } + + /* Enable external enabling for all possible clocks to conserve power */ + + lpc313x_enableexten((enum lpc313x_clockid_e)i); + + /* Set enable-out's for only the following clocks */ + + regaddr = LPC313X_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)lpc313x_defclk((enum lpc313x_clockid_e)i); + } + + /* Disable all fractional dividers */ + + for (i = 0; i < CGU_NFRACDIV; i++) + { + regaddr = LPC313X_CGU_FDC(i); + regval = getreg32(regaddr); + regval &= ~CGU_FDC_RUN; + putreg32(regval, i); + } +} |