/* | |
** ################################################################### | |
** Processors: LPC51U68JBD48 | |
** LPC51U68JBD64 | |
** | |
** Compilers: Keil ARM C/C++ Compiler | |
** GNU C Compiler | |
** IAR ANSI C/C++ Compiler for ARM | |
** MCUXpresso Compiler | |
** | |
** Reference manual: LPC51U68 User manual User manual Rev. 1.0 13 Dec 2017 | |
** Version: rev. 1.0, 2017-12-15 | |
** Build: b180802 | |
** | |
** Abstract: | |
** Provides a system configuration function and a global variable that | |
** contains the system frequency. It configures the device and initializes | |
** the oscillator (PLL) that is part of the microcontroller device. | |
** | |
** Copyright 2016 Freescale Semiconductor, Inc. | |
** Copyright 2016-2018 NXP | |
** | |
** SPDX-License-Identifier: BSD-3-Clause | |
** | |
** http: www.nxp.com | |
** mail: support@nxp.com | |
** | |
** Revisions: | |
** - rev. 1.0 (2017-12-15) | |
** Initial version. | |
** | |
** ################################################################### | |
*/ | |
/*! | |
* @file LPC51U68 | |
* @version 1.0 | |
* @date 2017-12-15 | |
* @brief Device specific configuration file for LPC51U68 (implementation file) | |
* | |
* Provides a system configuration function and a global variable that contains | |
* the system frequency. It configures the device and initializes the oscillator | |
* (PLL) that is part of the microcontroller device. | |
*/ | |
#include <stdint.h> | |
#include "fsl_device_registers.h" | |
#define NVALMAX (0x100) | |
#define PVALMAX (0x20) | |
#define MVALMAX (0x8000) | |
#define PLL_SSCG0_MDEC_VAL_P (0) /* MDEC is in bits 16 downto 0 */ | |
#define PLL_SSCG0_MDEC_VAL_M (0x1FFFFUL << PLL_SSCG0_MDEC_VAL_P) /* NDEC is in bits 9 downto 0 */ | |
#define PLL_NDEC_VAL_P (0) /* NDEC is in bits 9:0 */ | |
#define PLL_NDEC_VAL_M (0x3FFUL << PLL_NDEC_VAL_P) | |
#define PLL_PDEC_VAL_P (0) /* PDEC is in bits 6:0 */ | |
#define PLL_PDEC_VAL_M (0x3FFUL << PLL_PDEC_VAL_P) | |
extern void *__Vectors; | |
/* ---------------------------------------------------------------------------- | |
-- Core clock | |
---------------------------------------------------------------------------- */ | |
static const uint8_t wdtFreqLookup[32] = {0, 8, 12, 15, 18, 20, 24, 26, 28, 30, 32, 34, 36, 38, 40, 41, 42, 44, 45, 46, | |
48, 49, 50, 52, 53, 54, 56, 57, 58, 59, 60, 61}; | |
static uint32_t GetWdtOscFreq(void) | |
{ | |
uint8_t freq_sel, div_sel; | |
div_sel = ((SYSCON->WDTOSCCTRL & SYSCON_WDTOSCCTRL_DIVSEL_MASK) + 1) << 1; | |
freq_sel = wdtFreqLookup[((SYSCON->WDTOSCCTRL & SYSCON_WDTOSCCTRL_FREQSEL_MASK) >> SYSCON_WDTOSCCTRL_FREQSEL_SHIFT)]; | |
return ((uint32_t) freq_sel * 50000U)/((uint32_t)div_sel); | |
} | |
/* Find decoded N value for raw NDEC value */ | |
static uint32_t pllDecodeN(uint32_t NDEC) | |
{ | |
uint32_t n, x, i; | |
/* Find NDec */ | |
switch (NDEC) | |
{ | |
case 0xFFF: | |
n = 0; | |
break; | |
case 0x302: | |
n = 1; | |
break; | |
case 0x202: | |
n = 2; | |
break; | |
default: | |
x = 0x080; | |
n = 0xFFFFFFFF; | |
for (i = NVALMAX; ((i >= 3) && (n == 0xFFFFFFFF)); i--) | |
{ | |
x = (((x ^ (x >> 2) ^ (x >> 3) ^ (x >> 4)) & 1) << 7) | ((x >> 1) & 0x7F); | |
if ((x & (PLL_NDEC_VAL_M >> PLL_NDEC_VAL_P)) == NDEC) | |
{ | |
/* Decoded value of NDEC */ | |
n = i; | |
} | |
} | |
break; | |
} | |
return n; | |
} | |
/* Find decoded P value for raw PDEC value */ | |
static uint32_t pllDecodeP(uint32_t PDEC) | |
{ | |
uint32_t p, x, i; | |
/* Find PDec */ | |
switch (PDEC) | |
{ | |
case 0xFF: | |
p = 0; | |
break; | |
case 0x62: | |
p = 1; | |
break; | |
case 0x42: | |
p = 2; | |
break; | |
default: | |
x = 0x10; | |
p = 0xFFFFFFFF; | |
for (i = PVALMAX; ((i >= 3) && (p == 0xFFFFFFFF)); i--) | |
{ | |
x = (((x ^ (x >> 2)) & 1) << 4) | ((x >> 1) & 0xF); | |
if ((x & (PLL_PDEC_VAL_M >> PLL_PDEC_VAL_P)) == PDEC) | |
{ | |
/* Decoded value of PDEC */ | |
p = i; | |
} | |
} | |
break; | |
} | |
return p; | |
} | |
/* Find decoded M value for raw MDEC value */ | |
static uint32_t pllDecodeM(uint32_t MDEC) | |
{ | |
uint32_t m, i, x; | |
/* Find MDec */ | |
switch (MDEC) | |
{ | |
case 0xFFFFF: | |
m = 0; | |
break; | |
case 0x18003: | |
m = 1; | |
break; | |
case 0x10003: | |
m = 2; | |
break; | |
default: | |
x = 0x04000; | |
m = 0xFFFFFFFF; | |
for (i = MVALMAX; ((i >= 3) && (m == 0xFFFFFFFF)); i--) | |
{ | |
x = (((x ^ (x >> 1)) & 1) << 14) | ((x >> 1) & 0x3FFF); | |
if ((x & (PLL_SSCG0_MDEC_VAL_M >> PLL_SSCG0_MDEC_VAL_P)) == MDEC) | |
{ | |
/* Decoded value of MDEC */ | |
m = i; | |
} | |
} | |
break; | |
} | |
return m; | |
} | |
/* Get predivider (N) from PLL NDEC setting */ | |
static uint32_t findPllPreDiv(uint32_t ctrlReg, uint32_t nDecReg) | |
{ | |
uint32_t preDiv = 1; | |
/* Direct input is not used? */ | |
if ((ctrlReg & SYSCON_SYSPLLCTRL_DIRECTI_MASK) == 0) | |
{ | |
/* Decode NDEC value to get (N) pre divider */ | |
preDiv = pllDecodeN(nDecReg & 0x3FF); | |
if (preDiv == 0) | |
{ | |
preDiv = 1; | |
} | |
} | |
/* Adjusted by 1, directi is used to bypass */ | |
return preDiv; | |
} | |
/* Get postdivider (P) from PLL PDEC setting */ | |
static uint32_t findPllPostDiv(uint32_t ctrlReg, uint32_t pDecReg) | |
{ | |
uint32_t postDiv = 1; | |
/* Direct input is not used? */ | |
if ((ctrlReg & SYSCON_SYSPLLCTRL_DIRECTO_MASK) == 0) | |
{ | |
/* Decode PDEC value to get (P) post divider */ | |
postDiv = 2 * pllDecodeP(pDecReg & 0x7F); | |
if (postDiv == 0) | |
{ | |
postDiv = 2; | |
} | |
} | |
/* Adjusted by 1, directo is used to bypass */ | |
return postDiv; | |
} | |
/* Get multiplier (M) from PLL MDEC and BYPASS_FBDIV2 settings */ | |
static uint32_t findPllMMult(uint32_t ctrlReg, uint32_t mDecReg) | |
{ | |
uint32_t mMult = 1; | |
/* Decode MDEC value to get (M) multiplier */ | |
mMult = pllDecodeM(mDecReg & 0x1FFFF); | |
/* Extra multiply by 2 needed? */ | |
if ((ctrlReg & SYSCON_SYSPLLCTRL_BYPASSCCODIV2_MASK) == 0) | |
{ | |
mMult = mMult << 1; | |
} | |
if (mMult == 0) | |
{ | |
mMult = 1; | |
} | |
return mMult; | |
} | |
/* ---------------------------------------------------------------------------- | |
-- Core clock | |
---------------------------------------------------------------------------- */ | |
uint32_t SystemCoreClock = DEFAULT_SYSTEM_CLOCK; | |
/* ---------------------------------------------------------------------------- | |
-- SystemInit() | |
---------------------------------------------------------------------------- */ | |
void SystemInit (void) { | |
#if defined(__CODE_RED) | |
extern void(*const g_pfnVectors[]) (void); | |
SCB->VTOR = (uint32_t) &g_pfnVectors; | |
#else | |
extern void *__Vectors; | |
SCB->VTOR = (uint32_t) &__Vectors; | |
#endif | |
} | |
/* ---------------------------------------------------------------------------- | |
-- SystemCoreClockUpdate() | |
---------------------------------------------------------------------------- */ | |
void SystemCoreClockUpdate (void) { | |
uint32_t clkRate = 0; | |
uint32_t prediv, postdiv; | |
uint64_t workRate; | |
switch (SYSCON->MAINCLKSELB & SYSCON_MAINCLKSELB_SEL_MASK) | |
{ | |
case 0x00: /* MAINCLKSELA clock (main_clk_a)*/ | |
switch (SYSCON->MAINCLKSELA & SYSCON_MAINCLKSELA_SEL_MASK) | |
{ | |
case 0x00: /* FRO 12 MHz (fro_12m) */ | |
clkRate = CLK_FRO_12MHZ; | |
break; | |
case 0x01: /* CLKIN (clk_in) */ | |
clkRate = CLK_CLK_IN; | |
break; | |
case 0x02: /* Watchdog oscillator (wdt_clk) */ | |
clkRate = GetWdtOscFreq(); | |
break; | |
default: /* = 0x03 = FRO 96 or 48 MHz (fro_hf) */ | |
if (SYSCON->FROCTRL & SYSCON_FROCTRL_SEL_MASK) | |
{ | |
clkRate = CLK_FRO_96MHZ; | |
} | |
else | |
{ | |
clkRate = CLK_FRO_48MHZ; | |
} | |
break; | |
} | |
break; | |
case 0x02: /* System PLL clock (pll_clk)*/ | |
switch (SYSCON->SYSPLLCLKSEL & SYSCON_SYSPLLCLKSEL_SEL_MASK) | |
{ | |
case 0x00: /* FRO 12 MHz (fro_12m) */ | |
clkRate = CLK_FRO_12MHZ; | |
break; | |
case 0x01: /* CLKIN (clk_in) */ | |
clkRate = CLK_CLK_IN; | |
break; | |
case 0x02: /* Watchdog oscillator (wdt_clk) */ | |
clkRate = GetWdtOscFreq(); | |
break; | |
case 0x03: /* RTC oscillator 32 kHz output (32k_clk) */ | |
clkRate = CLK_RTC_32K_CLK; | |
break; | |
default: | |
break; | |
} | |
if ((SYSCON->SYSPLLCTRL & SYSCON_SYSPLLCTRL_BYPASS_MASK) == 0) | |
{ | |
/* PLL is not in bypass mode, get pre-divider, post-divider, and M divider */ | |
prediv = findPllPreDiv(SYSCON->SYSPLLCTRL, SYSCON->SYSPLLNDEC); | |
postdiv = findPllPostDiv(SYSCON->SYSPLLCTRL, SYSCON->SYSPLLPDEC); | |
/* Adjust input clock */ | |
clkRate = clkRate / prediv; | |
/* If using the SS, use the multiplier */ | |
if (SYSCON->SYSPLLSSCTRL1 & SYSCON_SYSPLLSSCTRL1_PD_MASK) | |
{ | |
/* MDEC used for rate */ | |
workRate = (uint64_t)clkRate * (uint64_t)findPllMMult(SYSCON->SYSPLLCTRL, SYSCON->SYSPLLSSCTRL0); | |
} | |
else | |
{ | |
/* SS multipler used for rate */ | |
workRate = 0; | |
/* Adjust by fractional */ | |
workRate = workRate + ((clkRate * (uint64_t)((SYSCON->SYSPLLSSCTRL1 & 0x7FF) >> 0)) / 0x800); | |
} | |
clkRate = workRate / ((uint64_t)postdiv); | |
} | |
break; | |
case 0x03: /* RTC oscillator 32 kHz output (32k_clk) */ | |
clkRate = CLK_RTC_32K_CLK; | |
break; | |
default: | |
break; | |
} | |
SystemCoreClock = clkRate / ((SYSCON->AHBCLKDIV & 0xFF) + 1); | |
} |