777 lines
26 KiB
C
777 lines
26 KiB
C
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/*****************************************************************************
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* Copyright 2003 - 2008 Broadcom Corporation. All rights reserved.
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*
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* Unless you and Broadcom execute a separate written software license
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* agreement governing use of this software, this software is licensed to you
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* under the terms of the GNU General Public License version 2, available at
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* http://www.broadcom.com/licenses/GPLv2.php (the "GPL").
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*
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* Notwithstanding the above, under no circumstances may you combine this
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* software in any way with any other Broadcom software provided under a
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* license other than the GPL, without Broadcom's express prior written
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* consent.
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*****************************************************************************/
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/****************************************************************************/
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/**
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* @file chipcHw.c
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*
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* @brief Low level Various CHIP clock controlling routines
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*
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* @note
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*
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* These routines provide basic clock controlling functionality only.
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*/
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/****************************************************************************/
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/* ---- Include Files ---------------------------------------------------- */
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#include <csp/errno.h>
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#include <csp/stdint.h>
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#include <csp/module.h>
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#include <mach/csp/chipcHw_def.h>
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#include <mach/csp/chipcHw_inline.h>
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#include <csp/reg.h>
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#include <csp/delay.h>
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/* ---- Private Constants and Types --------------------------------------- */
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/* VPM alignment algorithm uses this */
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#define MAX_PHASE_ADJUST_COUNT 0xFFFF /* Max number of times allowed to adjust the phase */
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#define MAX_PHASE_ALIGN_ATTEMPTS 10 /* Max number of attempt to align the phase */
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/* Local definition of clock type */
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#define PLL_CLOCK 1 /* PLL Clock */
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#define NON_PLL_CLOCK 2 /* Divider clock */
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static int chipcHw_divide(int num, int denom)
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__attribute__ ((section(".aramtext")));
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/****************************************************************************/
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/**
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* @brief Set clock fequency for miscellaneous configurable clocks
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*
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* This function sets clock frequency
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*
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* @return Configured clock frequency in hertz
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*
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*/
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/****************************************************************************/
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chipcHw_freq chipcHw_getClockFrequency(chipcHw_CLOCK_e clock /* [ IN ] Configurable clock */
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) {
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volatile uint32_t *pPLLReg = (uint32_t *) 0x0;
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volatile uint32_t *pClockCtrl = (uint32_t *) 0x0;
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volatile uint32_t *pDependentClock = (uint32_t *) 0x0;
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uint32_t vcoFreqPll1Hz = 0; /* Effective VCO frequency for PLL1 in Hz */
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uint32_t vcoFreqPll2Hz = 0; /* Effective VCO frequency for PLL2 in Hz */
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uint32_t dependentClockType = 0;
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uint32_t vcoHz = 0;
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/* Get VCO frequencies */
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if ((pChipcHw->PLLPreDivider & chipcHw_REG_PLL_PREDIVIDER_NDIV_MODE_MASK) != chipcHw_REG_PLL_PREDIVIDER_NDIV_MODE_INTEGER) {
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uint64_t adjustFreq = 0;
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vcoFreqPll1Hz = chipcHw_XTAL_FREQ_Hz *
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chipcHw_divide(chipcHw_REG_PLL_PREDIVIDER_P1, chipcHw_REG_PLL_PREDIVIDER_P2) *
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((pChipcHw->PLLPreDivider & chipcHw_REG_PLL_PREDIVIDER_NDIV_MASK) >>
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chipcHw_REG_PLL_PREDIVIDER_NDIV_SHIFT);
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/* Adjusted frequency due to chipcHw_REG_PLL_DIVIDER_NDIV_f_SS */
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adjustFreq = (uint64_t) chipcHw_XTAL_FREQ_Hz *
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(uint64_t) chipcHw_REG_PLL_DIVIDER_NDIV_f_SS *
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chipcHw_divide(chipcHw_REG_PLL_PREDIVIDER_P1, (chipcHw_REG_PLL_PREDIVIDER_P2 * (uint64_t) chipcHw_REG_PLL_DIVIDER_FRAC));
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vcoFreqPll1Hz += (uint32_t) adjustFreq;
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} else {
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vcoFreqPll1Hz = chipcHw_XTAL_FREQ_Hz *
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chipcHw_divide(chipcHw_REG_PLL_PREDIVIDER_P1, chipcHw_REG_PLL_PREDIVIDER_P2) *
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((pChipcHw->PLLPreDivider & chipcHw_REG_PLL_PREDIVIDER_NDIV_MASK) >>
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chipcHw_REG_PLL_PREDIVIDER_NDIV_SHIFT);
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}
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vcoFreqPll2Hz =
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chipcHw_XTAL_FREQ_Hz *
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chipcHw_divide(chipcHw_REG_PLL_PREDIVIDER_P1, chipcHw_REG_PLL_PREDIVIDER_P2) *
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((pChipcHw->PLLPreDivider2 & chipcHw_REG_PLL_PREDIVIDER_NDIV_MASK) >>
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chipcHw_REG_PLL_PREDIVIDER_NDIV_SHIFT);
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switch (clock) {
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case chipcHw_CLOCK_DDR:
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pPLLReg = &pChipcHw->DDRClock;
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vcoHz = vcoFreqPll1Hz;
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break;
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case chipcHw_CLOCK_ARM:
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pPLLReg = &pChipcHw->ARMClock;
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vcoHz = vcoFreqPll1Hz;
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break;
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case chipcHw_CLOCK_ESW:
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pPLLReg = &pChipcHw->ESWClock;
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vcoHz = vcoFreqPll1Hz;
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break;
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case chipcHw_CLOCK_VPM:
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pPLLReg = &pChipcHw->VPMClock;
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vcoHz = vcoFreqPll1Hz;
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break;
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case chipcHw_CLOCK_ESW125:
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pPLLReg = &pChipcHw->ESW125Clock;
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vcoHz = vcoFreqPll1Hz;
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break;
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case chipcHw_CLOCK_UART:
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pPLLReg = &pChipcHw->UARTClock;
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vcoHz = vcoFreqPll1Hz;
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break;
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case chipcHw_CLOCK_SDIO0:
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pPLLReg = &pChipcHw->SDIO0Clock;
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vcoHz = vcoFreqPll1Hz;
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break;
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case chipcHw_CLOCK_SDIO1:
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pPLLReg = &pChipcHw->SDIO1Clock;
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vcoHz = vcoFreqPll1Hz;
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break;
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case chipcHw_CLOCK_SPI:
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pPLLReg = &pChipcHw->SPIClock;
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vcoHz = vcoFreqPll1Hz;
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break;
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case chipcHw_CLOCK_ETM:
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pPLLReg = &pChipcHw->ETMClock;
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vcoHz = vcoFreqPll1Hz;
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break;
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case chipcHw_CLOCK_USB:
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pPLLReg = &pChipcHw->USBClock;
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vcoHz = vcoFreqPll2Hz;
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break;
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case chipcHw_CLOCK_LCD:
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pPLLReg = &pChipcHw->LCDClock;
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vcoHz = vcoFreqPll2Hz;
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break;
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case chipcHw_CLOCK_APM:
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pPLLReg = &pChipcHw->APMClock;
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vcoHz = vcoFreqPll2Hz;
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break;
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case chipcHw_CLOCK_BUS:
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pClockCtrl = &pChipcHw->ACLKClock;
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pDependentClock = &pChipcHw->ARMClock;
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vcoHz = vcoFreqPll1Hz;
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dependentClockType = PLL_CLOCK;
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break;
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case chipcHw_CLOCK_OTP:
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pClockCtrl = &pChipcHw->OTPClock;
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break;
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case chipcHw_CLOCK_I2C:
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pClockCtrl = &pChipcHw->I2CClock;
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break;
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case chipcHw_CLOCK_I2S0:
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pClockCtrl = &pChipcHw->I2S0Clock;
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break;
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case chipcHw_CLOCK_RTBUS:
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pClockCtrl = &pChipcHw->RTBUSClock;
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pDependentClock = &pChipcHw->ACLKClock;
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dependentClockType = NON_PLL_CLOCK;
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break;
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case chipcHw_CLOCK_APM100:
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pClockCtrl = &pChipcHw->APM100Clock;
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pDependentClock = &pChipcHw->APMClock;
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vcoHz = vcoFreqPll2Hz;
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dependentClockType = PLL_CLOCK;
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break;
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case chipcHw_CLOCK_TSC:
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pClockCtrl = &pChipcHw->TSCClock;
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break;
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case chipcHw_CLOCK_LED:
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pClockCtrl = &pChipcHw->LEDClock;
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break;
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case chipcHw_CLOCK_I2S1:
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pClockCtrl = &pChipcHw->I2S1Clock;
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break;
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}
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if (pPLLReg) {
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/* Obtain PLL clock frequency */
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if (*pPLLReg & chipcHw_REG_PLL_CLOCK_BYPASS_SELECT) {
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/* Return crystal clock frequency when bypassed */
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return chipcHw_XTAL_FREQ_Hz;
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} else if (clock == chipcHw_CLOCK_DDR) {
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/* DDR frequency is configured in PLLDivider register */
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return chipcHw_divide (vcoHz, (((pChipcHw->PLLDivider & 0xFF000000) >> 24) ? ((pChipcHw->PLLDivider & 0xFF000000) >> 24) : 256));
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} else {
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/* From chip revision number B0, LCD clock is internally divided by 2 */
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if ((pPLLReg == &pChipcHw->LCDClock) && (chipcHw_getChipRevisionNumber() != chipcHw_REV_NUMBER_A0)) {
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vcoHz >>= 1;
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}
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/* Obtain PLL clock frequency using VCO dividers */
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return chipcHw_divide(vcoHz, ((*pPLLReg & chipcHw_REG_PLL_CLOCK_MDIV_MASK) ? (*pPLLReg & chipcHw_REG_PLL_CLOCK_MDIV_MASK) : 256));
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}
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} else if (pClockCtrl) {
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/* Obtain divider clock frequency */
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uint32_t div;
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uint32_t freq = 0;
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if (*pClockCtrl & chipcHw_REG_DIV_CLOCK_BYPASS_SELECT) {
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/* Return crystal clock frequency when bypassed */
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return chipcHw_XTAL_FREQ_Hz;
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} else if (pDependentClock) {
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/* Identify the dependent clock frequency */
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switch (dependentClockType) {
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case PLL_CLOCK:
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if (*pDependentClock & chipcHw_REG_PLL_CLOCK_BYPASS_SELECT) {
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/* Use crystal clock frequency when dependent PLL clock is bypassed */
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freq = chipcHw_XTAL_FREQ_Hz;
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} else {
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/* Obtain PLL clock frequency using VCO dividers */
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div = *pDependentClock & chipcHw_REG_PLL_CLOCK_MDIV_MASK;
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freq = div ? chipcHw_divide(vcoHz, div) : 0;
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}
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break;
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case NON_PLL_CLOCK:
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if (pDependentClock == (uint32_t *) &pChipcHw->ACLKClock) {
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freq = chipcHw_getClockFrequency (chipcHw_CLOCK_BUS);
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} else {
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if (*pDependentClock & chipcHw_REG_DIV_CLOCK_BYPASS_SELECT) {
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/* Use crystal clock frequency when dependent divider clock is bypassed */
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freq = chipcHw_XTAL_FREQ_Hz;
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} else {
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/* Obtain divider clock frequency using XTAL dividers */
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div = *pDependentClock & chipcHw_REG_DIV_CLOCK_DIV_MASK;
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freq = chipcHw_divide (chipcHw_XTAL_FREQ_Hz, (div ? div : 256));
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}
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}
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break;
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}
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} else {
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/* Dependent on crystal clock */
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freq = chipcHw_XTAL_FREQ_Hz;
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}
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div = *pClockCtrl & chipcHw_REG_DIV_CLOCK_DIV_MASK;
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return chipcHw_divide(freq, (div ? div : 256));
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}
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return 0;
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}
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/****************************************************************************/
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/**
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* @brief Set clock fequency for miscellaneous configurable clocks
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*
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* This function sets clock frequency
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*
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* @return Configured clock frequency in Hz
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*
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*/
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/****************************************************************************/
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chipcHw_freq chipcHw_setClockFrequency(chipcHw_CLOCK_e clock, /* [ IN ] Configurable clock */
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uint32_t freq /* [ IN ] Clock frequency in Hz */
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) {
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volatile uint32_t *pPLLReg = (uint32_t *) 0x0;
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volatile uint32_t *pClockCtrl = (uint32_t *) 0x0;
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volatile uint32_t *pDependentClock = (uint32_t *) 0x0;
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uint32_t vcoFreqPll1Hz = 0; /* Effective VCO frequency for PLL1 in Hz */
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uint32_t desVcoFreqPll1Hz = 0; /* Desired VCO frequency for PLL1 in Hz */
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uint32_t vcoFreqPll2Hz = 0; /* Effective VCO frequency for PLL2 in Hz */
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uint32_t dependentClockType = 0;
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uint32_t vcoHz = 0;
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uint32_t desVcoHz = 0;
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/* Get VCO frequencies */
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if ((pChipcHw->PLLPreDivider & chipcHw_REG_PLL_PREDIVIDER_NDIV_MODE_MASK) != chipcHw_REG_PLL_PREDIVIDER_NDIV_MODE_INTEGER) {
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uint64_t adjustFreq = 0;
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vcoFreqPll1Hz = chipcHw_XTAL_FREQ_Hz *
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chipcHw_divide(chipcHw_REG_PLL_PREDIVIDER_P1, chipcHw_REG_PLL_PREDIVIDER_P2) *
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((pChipcHw->PLLPreDivider & chipcHw_REG_PLL_PREDIVIDER_NDIV_MASK) >>
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chipcHw_REG_PLL_PREDIVIDER_NDIV_SHIFT);
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/* Adjusted frequency due to chipcHw_REG_PLL_DIVIDER_NDIV_f_SS */
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adjustFreq = (uint64_t) chipcHw_XTAL_FREQ_Hz *
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(uint64_t) chipcHw_REG_PLL_DIVIDER_NDIV_f_SS *
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chipcHw_divide(chipcHw_REG_PLL_PREDIVIDER_P1, (chipcHw_REG_PLL_PREDIVIDER_P2 * (uint64_t) chipcHw_REG_PLL_DIVIDER_FRAC));
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vcoFreqPll1Hz += (uint32_t) adjustFreq;
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/* Desired VCO frequency */
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desVcoFreqPll1Hz = chipcHw_XTAL_FREQ_Hz *
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chipcHw_divide(chipcHw_REG_PLL_PREDIVIDER_P1, chipcHw_REG_PLL_PREDIVIDER_P2) *
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(((pChipcHw->PLLPreDivider & chipcHw_REG_PLL_PREDIVIDER_NDIV_MASK) >>
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chipcHw_REG_PLL_PREDIVIDER_NDIV_SHIFT) + 1);
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} else {
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vcoFreqPll1Hz = desVcoFreqPll1Hz = chipcHw_XTAL_FREQ_Hz *
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chipcHw_divide(chipcHw_REG_PLL_PREDIVIDER_P1, chipcHw_REG_PLL_PREDIVIDER_P2) *
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((pChipcHw->PLLPreDivider & chipcHw_REG_PLL_PREDIVIDER_NDIV_MASK) >>
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chipcHw_REG_PLL_PREDIVIDER_NDIV_SHIFT);
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}
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vcoFreqPll2Hz = chipcHw_XTAL_FREQ_Hz * chipcHw_divide(chipcHw_REG_PLL_PREDIVIDER_P1, chipcHw_REG_PLL_PREDIVIDER_P2) *
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((pChipcHw->PLLPreDivider2 & chipcHw_REG_PLL_PREDIVIDER_NDIV_MASK) >>
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chipcHw_REG_PLL_PREDIVIDER_NDIV_SHIFT);
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switch (clock) {
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case chipcHw_CLOCK_DDR:
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/* Configure the DDR_ctrl:BUS ratio settings */
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{
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|
|
REG_LOCAL_IRQ_SAVE;
|
||
|
|
/* Dvide DDR_phy by two to obtain DDR_ctrl clock */
|
||
|
|
pChipcHw->DDRClock = (pChipcHw->DDRClock & ~chipcHw_REG_PLL_CLOCK_TO_BUS_RATIO_MASK) | ((((freq / 2) / chipcHw_getClockFrequency(chipcHw_CLOCK_BUS)) - 1)
|
||
|
|
<< chipcHw_REG_PLL_CLOCK_TO_BUS_RATIO_SHIFT);
|
||
|
|
REG_LOCAL_IRQ_RESTORE;
|
||
|
|
}
|
||
|
|
pPLLReg = &pChipcHw->DDRClock;
|
||
|
|
vcoHz = vcoFreqPll1Hz;
|
||
|
|
desVcoHz = desVcoFreqPll1Hz;
|
||
|
|
break;
|
||
|
|
case chipcHw_CLOCK_ARM:
|
||
|
|
pPLLReg = &pChipcHw->ARMClock;
|
||
|
|
vcoHz = vcoFreqPll1Hz;
|
||
|
|
desVcoHz = desVcoFreqPll1Hz;
|
||
|
|
break;
|
||
|
|
case chipcHw_CLOCK_ESW:
|
||
|
|
pPLLReg = &pChipcHw->ESWClock;
|
||
|
|
vcoHz = vcoFreqPll1Hz;
|
||
|
|
desVcoHz = desVcoFreqPll1Hz;
|
||
|
|
break;
|
||
|
|
case chipcHw_CLOCK_VPM:
|
||
|
|
/* Configure the VPM:BUS ratio settings */
|
||
|
|
{
|
||
|
|
REG_LOCAL_IRQ_SAVE;
|
||
|
|
pChipcHw->VPMClock = (pChipcHw->VPMClock & ~chipcHw_REG_PLL_CLOCK_TO_BUS_RATIO_MASK) | ((chipcHw_divide (freq, chipcHw_getClockFrequency(chipcHw_CLOCK_BUS)) - 1)
|
||
|
|
<< chipcHw_REG_PLL_CLOCK_TO_BUS_RATIO_SHIFT);
|
||
|
|
REG_LOCAL_IRQ_RESTORE;
|
||
|
|
}
|
||
|
|
pPLLReg = &pChipcHw->VPMClock;
|
||
|
|
vcoHz = vcoFreqPll1Hz;
|
||
|
|
desVcoHz = desVcoFreqPll1Hz;
|
||
|
|
break;
|
||
|
|
case chipcHw_CLOCK_ESW125:
|
||
|
|
pPLLReg = &pChipcHw->ESW125Clock;
|
||
|
|
vcoHz = vcoFreqPll1Hz;
|
||
|
|
desVcoHz = desVcoFreqPll1Hz;
|
||
|
|
break;
|
||
|
|
case chipcHw_CLOCK_UART:
|
||
|
|
pPLLReg = &pChipcHw->UARTClock;
|
||
|
|
vcoHz = vcoFreqPll1Hz;
|
||
|
|
desVcoHz = desVcoFreqPll1Hz;
|
||
|
|
break;
|
||
|
|
case chipcHw_CLOCK_SDIO0:
|
||
|
|
pPLLReg = &pChipcHw->SDIO0Clock;
|
||
|
|
vcoHz = vcoFreqPll1Hz;
|
||
|
|
desVcoHz = desVcoFreqPll1Hz;
|
||
|
|
break;
|
||
|
|
case chipcHw_CLOCK_SDIO1:
|
||
|
|
pPLLReg = &pChipcHw->SDIO1Clock;
|
||
|
|
vcoHz = vcoFreqPll1Hz;
|
||
|
|
desVcoHz = desVcoFreqPll1Hz;
|
||
|
|
break;
|
||
|
|
case chipcHw_CLOCK_SPI:
|
||
|
|
pPLLReg = &pChipcHw->SPIClock;
|
||
|
|
vcoHz = vcoFreqPll1Hz;
|
||
|
|
desVcoHz = desVcoFreqPll1Hz;
|
||
|
|
break;
|
||
|
|
case chipcHw_CLOCK_ETM:
|
||
|
|
pPLLReg = &pChipcHw->ETMClock;
|
||
|
|
vcoHz = vcoFreqPll1Hz;
|
||
|
|
desVcoHz = desVcoFreqPll1Hz;
|
||
|
|
break;
|
||
|
|
case chipcHw_CLOCK_USB:
|
||
|
|
pPLLReg = &pChipcHw->USBClock;
|
||
|
|
vcoHz = vcoFreqPll2Hz;
|
||
|
|
desVcoHz = vcoFreqPll2Hz;
|
||
|
|
break;
|
||
|
|
case chipcHw_CLOCK_LCD:
|
||
|
|
pPLLReg = &pChipcHw->LCDClock;
|
||
|
|
vcoHz = vcoFreqPll2Hz;
|
||
|
|
desVcoHz = vcoFreqPll2Hz;
|
||
|
|
break;
|
||
|
|
case chipcHw_CLOCK_APM:
|
||
|
|
pPLLReg = &pChipcHw->APMClock;
|
||
|
|
vcoHz = vcoFreqPll2Hz;
|
||
|
|
desVcoHz = vcoFreqPll2Hz;
|
||
|
|
break;
|
||
|
|
case chipcHw_CLOCK_BUS:
|
||
|
|
pClockCtrl = &pChipcHw->ACLKClock;
|
||
|
|
pDependentClock = &pChipcHw->ARMClock;
|
||
|
|
vcoHz = vcoFreqPll1Hz;
|
||
|
|
desVcoHz = desVcoFreqPll1Hz;
|
||
|
|
dependentClockType = PLL_CLOCK;
|
||
|
|
break;
|
||
|
|
case chipcHw_CLOCK_OTP:
|
||
|
|
pClockCtrl = &pChipcHw->OTPClock;
|
||
|
|
break;
|
||
|
|
case chipcHw_CLOCK_I2C:
|
||
|
|
pClockCtrl = &pChipcHw->I2CClock;
|
||
|
|
break;
|
||
|
|
case chipcHw_CLOCK_I2S0:
|
||
|
|
pClockCtrl = &pChipcHw->I2S0Clock;
|
||
|
|
break;
|
||
|
|
case chipcHw_CLOCK_RTBUS:
|
||
|
|
pClockCtrl = &pChipcHw->RTBUSClock;
|
||
|
|
pDependentClock = &pChipcHw->ACLKClock;
|
||
|
|
dependentClockType = NON_PLL_CLOCK;
|
||
|
|
break;
|
||
|
|
case chipcHw_CLOCK_APM100:
|
||
|
|
pClockCtrl = &pChipcHw->APM100Clock;
|
||
|
|
pDependentClock = &pChipcHw->APMClock;
|
||
|
|
vcoHz = vcoFreqPll2Hz;
|
||
|
|
desVcoHz = vcoFreqPll2Hz;
|
||
|
|
dependentClockType = PLL_CLOCK;
|
||
|
|
break;
|
||
|
|
case chipcHw_CLOCK_TSC:
|
||
|
|
pClockCtrl = &pChipcHw->TSCClock;
|
||
|
|
break;
|
||
|
|
case chipcHw_CLOCK_LED:
|
||
|
|
pClockCtrl = &pChipcHw->LEDClock;
|
||
|
|
break;
|
||
|
|
case chipcHw_CLOCK_I2S1:
|
||
|
|
pClockCtrl = &pChipcHw->I2S1Clock;
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (pPLLReg) {
|
||
|
|
/* Select XTAL as bypass source */
|
||
|
|
reg32_modify_and(pPLLReg, ~chipcHw_REG_PLL_CLOCK_SOURCE_GPIO);
|
||
|
|
reg32_modify_or(pPLLReg, chipcHw_REG_PLL_CLOCK_BYPASS_SELECT);
|
||
|
|
/* For DDR settings use only the PLL divider clock */
|
||
|
|
if (pPLLReg == &pChipcHw->DDRClock) {
|
||
|
|
/* Set M1DIV for PLL1, which controls the DDR clock */
|
||
|
|
reg32_write(&pChipcHw->PLLDivider, (pChipcHw->PLLDivider & 0x00FFFFFF) | ((chipcHw_REG_PLL_DIVIDER_MDIV (desVcoHz, freq)) << 24));
|
||
|
|
/* Calculate expected frequency */
|
||
|
|
freq = chipcHw_divide(vcoHz, (((pChipcHw->PLLDivider & 0xFF000000) >> 24) ? ((pChipcHw->PLLDivider & 0xFF000000) >> 24) : 256));
|
||
|
|
} else {
|
||
|
|
/* From chip revision number B0, LCD clock is internally divided by 2 */
|
||
|
|
if ((pPLLReg == &pChipcHw->LCDClock) && (chipcHw_getChipRevisionNumber() != chipcHw_REV_NUMBER_A0)) {
|
||
|
|
desVcoHz >>= 1;
|
||
|
|
vcoHz >>= 1;
|
||
|
|
}
|
||
|
|
/* Set MDIV to change the frequency */
|
||
|
|
reg32_modify_and(pPLLReg, ~(chipcHw_REG_PLL_CLOCK_MDIV_MASK));
|
||
|
|
reg32_modify_or(pPLLReg, chipcHw_REG_PLL_DIVIDER_MDIV(desVcoHz, freq));
|
||
|
|
/* Calculate expected frequency */
|
||
|
|
freq = chipcHw_divide(vcoHz, ((*(pPLLReg) & chipcHw_REG_PLL_CLOCK_MDIV_MASK) ? (*(pPLLReg) & chipcHw_REG_PLL_CLOCK_MDIV_MASK) : 256));
|
||
|
|
}
|
||
|
|
/* Wait for for atleast 200ns as per the protocol to change frequency */
|
||
|
|
udelay(1);
|
||
|
|
/* Do not bypass */
|
||
|
|
reg32_modify_and(pPLLReg, ~chipcHw_REG_PLL_CLOCK_BYPASS_SELECT);
|
||
|
|
/* Return the configured frequency */
|
||
|
|
return freq;
|
||
|
|
} else if (pClockCtrl) {
|
||
|
|
uint32_t divider = 0;
|
||
|
|
|
||
|
|
/* Divider clock should not be bypassed */
|
||
|
|
reg32_modify_and(pClockCtrl,
|
||
|
|
~chipcHw_REG_DIV_CLOCK_BYPASS_SELECT);
|
||
|
|
|
||
|
|
/* Identify the clock source */
|
||
|
|
if (pDependentClock) {
|
||
|
|
switch (dependentClockType) {
|
||
|
|
case PLL_CLOCK:
|
||
|
|
divider = chipcHw_divide(chipcHw_divide (desVcoHz, (*pDependentClock & chipcHw_REG_PLL_CLOCK_MDIV_MASK)), freq);
|
||
|
|
break;
|
||
|
|
case NON_PLL_CLOCK:
|
||
|
|
{
|
||
|
|
uint32_t sourceClock = 0;
|
||
|
|
|
||
|
|
if (pDependentClock == (uint32_t *) &pChipcHw->ACLKClock) {
|
||
|
|
sourceClock = chipcHw_getClockFrequency (chipcHw_CLOCK_BUS);
|
||
|
|
} else {
|
||
|
|
uint32_t div = *pDependentClock & chipcHw_REG_DIV_CLOCK_DIV_MASK;
|
||
|
|
sourceClock = chipcHw_divide (chipcHw_XTAL_FREQ_Hz, ((div) ? div : 256));
|
||
|
|
}
|
||
|
|
divider = chipcHw_divide(sourceClock, freq);
|
||
|
|
}
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
} else {
|
||
|
|
divider = chipcHw_divide(chipcHw_XTAL_FREQ_Hz, freq);
|
||
|
|
}
|
||
|
|
|
||
|
|
if (divider) {
|
||
|
|
REG_LOCAL_IRQ_SAVE;
|
||
|
|
/* Set the divider to obtain the required frequency */
|
||
|
|
*pClockCtrl = (*pClockCtrl & (~chipcHw_REG_DIV_CLOCK_DIV_MASK)) | (((divider > 256) ? chipcHw_REG_DIV_CLOCK_DIV_256 : divider) & chipcHw_REG_DIV_CLOCK_DIV_MASK);
|
||
|
|
REG_LOCAL_IRQ_RESTORE;
|
||
|
|
return freq;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
EXPORT_SYMBOL(chipcHw_setClockFrequency);
|
||
|
|
|
||
|
|
/****************************************************************************/
|
||
|
|
/**
|
||
|
|
* @brief Set VPM clock in sync with BUS clock for Chip Rev #A0
|
||
|
|
*
|
||
|
|
* This function does the phase adjustment between VPM and BUS clock
|
||
|
|
*
|
||
|
|
* @return >= 0 : On success (# of adjustment required)
|
||
|
|
* -1 : On failure
|
||
|
|
*
|
||
|
|
*/
|
||
|
|
/****************************************************************************/
|
||
|
|
static int vpmPhaseAlignA0(void)
|
||
|
|
{
|
||
|
|
uint32_t phaseControl;
|
||
|
|
uint32_t phaseValue;
|
||
|
|
uint32_t prevPhaseComp;
|
||
|
|
int iter = 0;
|
||
|
|
int adjustCount = 0;
|
||
|
|
int count = 0;
|
||
|
|
|
||
|
|
for (iter = 0; (iter < MAX_PHASE_ALIGN_ATTEMPTS) && (adjustCount < MAX_PHASE_ADJUST_COUNT); iter++) {
|
||
|
|
phaseControl = (pChipcHw->VPMClock & chipcHw_REG_PLL_CLOCK_PHASE_CONTROL_MASK) >> chipcHw_REG_PLL_CLOCK_PHASE_CONTROL_SHIFT;
|
||
|
|
phaseValue = 0;
|
||
|
|
prevPhaseComp = 0;
|
||
|
|
|
||
|
|
/* Step 1: Look for falling PH_COMP transition */
|
||
|
|
|
||
|
|
/* Read the contents of VPM Clock resgister */
|
||
|
|
phaseValue = pChipcHw->VPMClock;
|
||
|
|
do {
|
||
|
|
/* Store previous value of phase comparator */
|
||
|
|
prevPhaseComp = phaseValue & chipcHw_REG_PLL_CLOCK_PHASE_COMP;
|
||
|
|
/* Change the value of PH_CTRL. */
|
||
|
|
reg32_write(&pChipcHw->VPMClock, (pChipcHw->VPMClock & (~chipcHw_REG_PLL_CLOCK_PHASE_CONTROL_MASK)) | (phaseControl << chipcHw_REG_PLL_CLOCK_PHASE_CONTROL_SHIFT));
|
||
|
|
/* Wait atleast 20 ns */
|
||
|
|
udelay(1);
|
||
|
|
/* Toggle the LOAD_CH after phase control is written. */
|
||
|
|
pChipcHw->VPMClock ^= chipcHw_REG_PLL_CLOCK_PHASE_UPDATE_ENABLE;
|
||
|
|
/* Read the contents of VPM Clock resgister. */
|
||
|
|
phaseValue = pChipcHw->VPMClock;
|
||
|
|
|
||
|
|
if ((phaseValue & chipcHw_REG_PLL_CLOCK_PHASE_COMP) == 0x0) {
|
||
|
|
phaseControl = (0x3F & (phaseControl - 1));
|
||
|
|
} else {
|
||
|
|
/* Increment to the Phase count value for next write, if Phase is not stable. */
|
||
|
|
phaseControl = (0x3F & (phaseControl + 1));
|
||
|
|
}
|
||
|
|
/* Count number of adjustment made */
|
||
|
|
adjustCount++;
|
||
|
|
} while (((prevPhaseComp == (phaseValue & chipcHw_REG_PLL_CLOCK_PHASE_COMP)) || /* Look for a transition */
|
||
|
|
((phaseValue & chipcHw_REG_PLL_CLOCK_PHASE_COMP) != 0x0)) && /* Look for a falling edge */
|
||
|
|
(adjustCount < MAX_PHASE_ADJUST_COUNT) /* Do not exceed the limit while trying */
|
||
|
|
);
|
||
|
|
|
||
|
|
if (adjustCount >= MAX_PHASE_ADJUST_COUNT) {
|
||
|
|
/* Failed to align VPM phase after MAX_PHASE_ADJUST_COUNT tries */
|
||
|
|
return -1;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* Step 2: Keep moving forward to make sure falling PH_COMP transition was valid */
|
||
|
|
|
||
|
|
for (count = 0; (count < 5) && ((phaseValue & chipcHw_REG_PLL_CLOCK_PHASE_COMP) == 0); count++) {
|
||
|
|
phaseControl = (0x3F & (phaseControl + 1));
|
||
|
|
reg32_write(&pChipcHw->VPMClock, (pChipcHw->VPMClock & (~chipcHw_REG_PLL_CLOCK_PHASE_CONTROL_MASK)) | (phaseControl << chipcHw_REG_PLL_CLOCK_PHASE_CONTROL_SHIFT));
|
||
|
|
/* Wait atleast 20 ns */
|
||
|
|
udelay(1);
|
||
|
|
/* Toggle the LOAD_CH after phase control is written. */
|
||
|
|
pChipcHw->VPMClock ^= chipcHw_REG_PLL_CLOCK_PHASE_UPDATE_ENABLE;
|
||
|
|
phaseValue = pChipcHw->VPMClock;
|
||
|
|
/* Count number of adjustment made */
|
||
|
|
adjustCount++;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (adjustCount >= MAX_PHASE_ADJUST_COUNT) {
|
||
|
|
/* Failed to align VPM phase after MAX_PHASE_ADJUST_COUNT tries */
|
||
|
|
return -1;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (count != 5) {
|
||
|
|
/* Detected false transition */
|
||
|
|
continue;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* Step 3: Keep moving backward to make sure falling PH_COMP transition was stable */
|
||
|
|
|
||
|
|
for (count = 0; (count < 3) && ((phaseValue & chipcHw_REG_PLL_CLOCK_PHASE_COMP) == 0); count++) {
|
||
|
|
phaseControl = (0x3F & (phaseControl - 1));
|
||
|
|
reg32_write(&pChipcHw->VPMClock, (pChipcHw->VPMClock & (~chipcHw_REG_PLL_CLOCK_PHASE_CONTROL_MASK)) | (phaseControl << chipcHw_REG_PLL_CLOCK_PHASE_CONTROL_SHIFT));
|
||
|
|
/* Wait atleast 20 ns */
|
||
|
|
udelay(1);
|
||
|
|
/* Toggle the LOAD_CH after phase control is written. */
|
||
|
|
pChipcHw->VPMClock ^= chipcHw_REG_PLL_CLOCK_PHASE_UPDATE_ENABLE;
|
||
|
|
phaseValue = pChipcHw->VPMClock;
|
||
|
|
/* Count number of adjustment made */
|
||
|
|
adjustCount++;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (adjustCount >= MAX_PHASE_ADJUST_COUNT) {
|
||
|
|
/* Failed to align VPM phase after MAX_PHASE_ADJUST_COUNT tries */
|
||
|
|
return -1;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (count != 3) {
|
||
|
|
/* Detected noisy transition */
|
||
|
|
continue;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* Step 4: Keep moving backward before the original transition took place. */
|
||
|
|
|
||
|
|
for (count = 0; (count < 5); count++) {
|
||
|
|
phaseControl = (0x3F & (phaseControl - 1));
|
||
|
|
reg32_write(&pChipcHw->VPMClock, (pChipcHw->VPMClock & (~chipcHw_REG_PLL_CLOCK_PHASE_CONTROL_MASK)) | (phaseControl << chipcHw_REG_PLL_CLOCK_PHASE_CONTROL_SHIFT));
|
||
|
|
/* Wait atleast 20 ns */
|
||
|
|
udelay(1);
|
||
|
|
/* Toggle the LOAD_CH after phase control is written. */
|
||
|
|
pChipcHw->VPMClock ^= chipcHw_REG_PLL_CLOCK_PHASE_UPDATE_ENABLE;
|
||
|
|
phaseValue = pChipcHw->VPMClock;
|
||
|
|
/* Count number of adjustment made */
|
||
|
|
adjustCount++;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (adjustCount >= MAX_PHASE_ADJUST_COUNT) {
|
||
|
|
/* Failed to align VPM phase after MAX_PHASE_ADJUST_COUNT tries */
|
||
|
|
return -1;
|
||
|
|
}
|
||
|
|
|
||
|
|
if ((phaseValue & chipcHw_REG_PLL_CLOCK_PHASE_COMP) == 0) {
|
||
|
|
/* Detected false transition */
|
||
|
|
continue;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* Step 5: Re discover the valid transition */
|
||
|
|
|
||
|
|
do {
|
||
|
|
/* Store previous value of phase comparator */
|
||
|
|
prevPhaseComp = phaseValue;
|
||
|
|
/* Change the value of PH_CTRL. */
|
||
|
|
reg32_write(&pChipcHw->VPMClock, (pChipcHw->VPMClock & (~chipcHw_REG_PLL_CLOCK_PHASE_CONTROL_MASK)) | (phaseControl << chipcHw_REG_PLL_CLOCK_PHASE_CONTROL_SHIFT));
|
||
|
|
/* Wait atleast 20 ns */
|
||
|
|
udelay(1);
|
||
|
|
/* Toggle the LOAD_CH after phase control is written. */
|
||
|
|
pChipcHw->VPMClock ^=
|
||
|
|
chipcHw_REG_PLL_CLOCK_PHASE_UPDATE_ENABLE;
|
||
|
|
/* Read the contents of VPM Clock resgister. */
|
||
|
|
phaseValue = pChipcHw->VPMClock;
|
||
|
|
|
||
|
|
if ((phaseValue & chipcHw_REG_PLL_CLOCK_PHASE_COMP) == 0x0) {
|
||
|
|
phaseControl = (0x3F & (phaseControl - 1));
|
||
|
|
} else {
|
||
|
|
/* Increment to the Phase count value for next write, if Phase is not stable. */
|
||
|
|
phaseControl = (0x3F & (phaseControl + 1));
|
||
|
|
}
|
||
|
|
|
||
|
|
/* Count number of adjustment made */
|
||
|
|
adjustCount++;
|
||
|
|
} while (((prevPhaseComp == (phaseValue & chipcHw_REG_PLL_CLOCK_PHASE_COMP)) || ((phaseValue & chipcHw_REG_PLL_CLOCK_PHASE_COMP) != 0x0)) && (adjustCount < MAX_PHASE_ADJUST_COUNT));
|
||
|
|
|
||
|
|
if (adjustCount >= MAX_PHASE_ADJUST_COUNT) {
|
||
|
|
/* Failed to align VPM phase after MAX_PHASE_ADJUST_COUNT tries */
|
||
|
|
return -1;
|
||
|
|
} else {
|
||
|
|
/* Valid phase must have detected */
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
/* For VPM Phase should be perfectly aligned. */
|
||
|
|
phaseControl = (((pChipcHw->VPMClock >> chipcHw_REG_PLL_CLOCK_PHASE_CONTROL_SHIFT) - 1) & 0x3F);
|
||
|
|
{
|
||
|
|
REG_LOCAL_IRQ_SAVE;
|
||
|
|
|
||
|
|
pChipcHw->VPMClock = (pChipcHw->VPMClock & ~chipcHw_REG_PLL_CLOCK_PHASE_CONTROL_MASK) | (phaseControl << chipcHw_REG_PLL_CLOCK_PHASE_CONTROL_SHIFT);
|
||
|
|
/* Load new phase value */
|
||
|
|
pChipcHw->VPMClock ^= chipcHw_REG_PLL_CLOCK_PHASE_UPDATE_ENABLE;
|
||
|
|
|
||
|
|
REG_LOCAL_IRQ_RESTORE;
|
||
|
|
}
|
||
|
|
/* Return the status */
|
||
|
|
return (int)adjustCount;
|
||
|
|
}
|
||
|
|
|
||
|
|
/****************************************************************************/
|
||
|
|
/**
|
||
|
|
* @brief Set VPM clock in sync with BUS clock
|
||
|
|
*
|
||
|
|
* This function does the phase adjustment between VPM and BUS clock
|
||
|
|
*
|
||
|
|
* @return >= 0 : On success (# of adjustment required)
|
||
|
|
* -1 : On failure
|
||
|
|
*
|
||
|
|
*/
|
||
|
|
/****************************************************************************/
|
||
|
|
int chipcHw_vpmPhaseAlign(void)
|
||
|
|
{
|
||
|
|
|
||
|
|
if (chipcHw_getChipRevisionNumber() == chipcHw_REV_NUMBER_A0) {
|
||
|
|
return vpmPhaseAlignA0();
|
||
|
|
} else {
|
||
|
|
uint32_t phaseControl = chipcHw_getVpmPhaseControl();
|
||
|
|
uint32_t phaseValue = 0;
|
||
|
|
int adjustCount = 0;
|
||
|
|
|
||
|
|
/* Disable VPM access */
|
||
|
|
pChipcHw->Spare1 &= ~chipcHw_REG_SPARE1_VPM_BUS_ACCESS_ENABLE;
|
||
|
|
/* Disable HW VPM phase alignment */
|
||
|
|
chipcHw_vpmHwPhaseAlignDisable();
|
||
|
|
/* Enable SW VPM phase alignment */
|
||
|
|
chipcHw_vpmSwPhaseAlignEnable();
|
||
|
|
/* Adjust VPM phase */
|
||
|
|
while (adjustCount < MAX_PHASE_ADJUST_COUNT) {
|
||
|
|
phaseValue = chipcHw_getVpmHwPhaseAlignStatus();
|
||
|
|
|
||
|
|
/* Adjust phase control value */
|
||
|
|
if (phaseValue > 0xF) {
|
||
|
|
/* Increment phase control value */
|
||
|
|
phaseControl++;
|
||
|
|
} else if (phaseValue < 0xF) {
|
||
|
|
/* Decrement phase control value */
|
||
|
|
phaseControl--;
|
||
|
|
} else {
|
||
|
|
/* Enable VPM access */
|
||
|
|
pChipcHw->Spare1 |= chipcHw_REG_SPARE1_VPM_BUS_ACCESS_ENABLE;
|
||
|
|
/* Return adjust count */
|
||
|
|
return adjustCount;
|
||
|
|
}
|
||
|
|
/* Change the value of PH_CTRL. */
|
||
|
|
reg32_write(&pChipcHw->VPMClock, (pChipcHw->VPMClock & (~chipcHw_REG_PLL_CLOCK_PHASE_CONTROL_MASK)) | (phaseControl << chipcHw_REG_PLL_CLOCK_PHASE_CONTROL_SHIFT));
|
||
|
|
/* Wait atleast 20 ns */
|
||
|
|
udelay(1);
|
||
|
|
/* Toggle the LOAD_CH after phase control is written. */
|
||
|
|
pChipcHw->VPMClock ^= chipcHw_REG_PLL_CLOCK_PHASE_UPDATE_ENABLE;
|
||
|
|
/* Count adjustment */
|
||
|
|
adjustCount++;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
/* Disable VPM access */
|
||
|
|
pChipcHw->Spare1 &= ~chipcHw_REG_SPARE1_VPM_BUS_ACCESS_ENABLE;
|
||
|
|
return -1;
|
||
|
|
}
|
||
|
|
|
||
|
|
/****************************************************************************/
|
||
|
|
/**
|
||
|
|
* @brief Local Divide function
|
||
|
|
*
|
||
|
|
* This function does the divide
|
||
|
|
*
|
||
|
|
* @return divide value
|
||
|
|
*
|
||
|
|
*/
|
||
|
|
/****************************************************************************/
|
||
|
|
static int chipcHw_divide(int num, int denom)
|
||
|
|
{
|
||
|
|
int r;
|
||
|
|
int t = 1;
|
||
|
|
|
||
|
|
/* Shift denom and t up to the largest value to optimize algorithm */
|
||
|
|
/* t contains the units of each divide */
|
||
|
|
while ((denom & 0x40000000) == 0) { /* fails if denom=0 */
|
||
|
|
denom = denom << 1;
|
||
|
|
t = t << 1;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* Intialize the result */
|
||
|
|
r = 0;
|
||
|
|
|
||
|
|
do {
|
||
|
|
/* Determine if there exists a positive remainder */
|
||
|
|
if ((num - denom) >= 0) {
|
||
|
|
/* Accumlate t to the result and calculate a new remainder */
|
||
|
|
num = num - denom;
|
||
|
|
r = r + t;
|
||
|
|
}
|
||
|
|
/* Continue to shift denom and shift t down to 0 */
|
||
|
|
denom = denom >> 1;
|
||
|
|
t = t >> 1;
|
||
|
|
} while (t != 0);
|
||
|
|
|
||
|
|
return r;
|
||
|
|
}
|