/* * * (C) Copyright 2000-2003 * Wolfgang Denk, DENX Software Engineering, wd@denx.de. * * Copyright (C) 2004-2008, 2012 Freescale Semiconductor, Inc. * TsiChung Liew (Tsi-Chung.Liew@freescale.com) * * SPDX-License-Identifier: GPL-2.0+ */ #include #include #include #include DECLARE_GLOBAL_DATA_PTR; /* PLL min/max specifications */ #define MAX_FVCO 500000 /* KHz */ #define MAX_FSYS 80000 /* KHz */ #define MIN_FSYS 58333 /* KHz */ #ifdef CONFIG_MCF5301x #define FREF 20000 /* KHz */ #define MAX_MFD 63 /* Multiplier */ #define MIN_MFD 0 /* Multiplier */ #define USBDIV 8 /* Low Power Divider specifications */ #define MIN_LPD (0) /* Divider (not encoded) */ #define MAX_LPD (15) /* Divider (not encoded) */ #define DEFAULT_LPD (0) /* Divider (not encoded) */ #endif #ifdef CONFIG_MCF532x #define FREF 16000 /* KHz */ #define MAX_MFD 135 /* Multiplier */ #define MIN_MFD 88 /* Multiplier */ /* Low Power Divider specifications */ #define MIN_LPD (1 << 0) /* Divider (not encoded) */ #define MAX_LPD (1 << 15) /* Divider (not encoded) */ #define DEFAULT_LPD (1 << 1) /* Divider (not encoded) */ #endif #define BUSDIV 6 /* Divider */ /* Get the value of the current system clock */ int get_sys_clock(void) { ccm_t *ccm = (ccm_t *)(MMAP_CCM); pll_t *pll = (pll_t *)(MMAP_PLL); int divider; /* Test to see if device is in LIMP mode */ if (in_be16(&ccm->misccr) & CCM_MISCCR_LIMP) { divider = in_be16(&ccm->cdr) & CCM_CDR_LPDIV(0xF); #ifdef CONFIG_MCF5301x return (FREF / (3 * (1 << divider))); #endif #ifdef CONFIG_MCF532x return (FREF / (2 << divider)); #endif } else { #ifdef CONFIG_MCF5301x u32 pfdr = (in_be32(&pll->pcr) & 0x3F) + 1; u32 refdiv = (1 << ((in_be32(&pll->pcr) & PLL_PCR_REFDIV(7)) >> 8)); u32 busdiv = ((in_be32(&pll->pdr) & 0x00F0) >> 4) + 1; return (((FREF * pfdr) / refdiv) / busdiv); #endif #ifdef CONFIG_MCF532x return (FREF * in_8(&pll->pfdr)) / (BUSDIV * 4); #endif } } /* * Initialize the Low Power Divider circuit * * Parameters: * div Desired system frequency divider * * Return Value: * The resulting output system frequency */ int clock_limp(int div) { ccm_t *ccm = (ccm_t *)(MMAP_CCM); u32 temp; /* Check bounds of divider */ if (div < MIN_LPD) div = MIN_LPD; if (div > MAX_LPD) div = MAX_LPD; /* Save of the current value of the SSIDIV so we don't overwrite the value */ temp = (in_be16(&ccm->cdr) & CCM_CDR_SSIDIV(0xFF)); /* Apply the divider to the system clock */ out_be16(&ccm->cdr, CCM_CDR_LPDIV(div) | CCM_CDR_SSIDIV(temp)); setbits_be16(&ccm->misccr, CCM_MISCCR_LIMP); return (FREF / (3 * (1 << div))); } /* Exit low power LIMP mode */ int clock_exit_limp(void) { ccm_t *ccm = (ccm_t *)(MMAP_CCM); int fout; /* Exit LIMP mode */ clrbits_be16(&ccm->misccr, CCM_MISCCR_LIMP); /* Wait for PLL to lock */ while (!(in_be16(&ccm->misccr) & CCM_MISCCR_PLL_LOCK)) ; fout = get_sys_clock(); return fout; } /* Initialize the PLL * * Parameters: * fref PLL reference clock frequency in KHz * fsys Desired PLL output frequency in KHz * flags Operating parameters * * Return Value: * The resulting output system frequency */ int clock_pll(int fsys, int flags) { #ifdef CONFIG_MCF532x u32 *sdram_workaround = (u32 *)(MMAP_SDRAM + 0x80); #endif sdram_t *sdram = (sdram_t *)(MMAP_SDRAM); pll_t *pll = (pll_t *)(MMAP_PLL); int fref, temp, fout, mfd; u32 i; fref = FREF; if (fsys == 0) { /* Return current PLL output */ #ifdef CONFIG_MCF5301x u32 busdiv = ((in_be32(&pll->pdr) >> 4) & 0x0F) + 1; mfd = (in_be32(&pll->pcr) & 0x3F) + 1; return (fref * mfd) / busdiv; #endif #ifdef CONFIG_MCF532x mfd = in_8(&pll->pfdr); return (fref * mfd / (BUSDIV * 4)); #endif } /* Check bounds of requested system clock */ if (fsys > MAX_FSYS) fsys = MAX_FSYS; if (fsys < MIN_FSYS) fsys = MIN_FSYS; /* * Multiplying by 100 when calculating the temp value, * and then dividing by 100 to calculate the mfd allows * for exact values without needing to include floating * point libraries. */ temp = (100 * fsys) / fref; #ifdef CONFIG_MCF5301x mfd = (BUSDIV * temp) / 100; /* Determine the output frequency for selected values */ fout = ((fref * mfd) / BUSDIV); #endif #ifdef CONFIG_MCF532x mfd = (4 * BUSDIV * temp) / 100; /* Determine the output frequency for selected values */ fout = ((fref * mfd) / (BUSDIV * 4)); #endif /* must not tamper with SDRAMC if running from SDRAM */ #if !defined(CONFIG_MONITOR_IS_IN_RAM) /* * Check to see if the SDRAM has already been initialized. * If it has then the SDRAM needs to be put into self refresh * mode before reprogramming the PLL. */ if (in_be32(&sdram->ctrl) & SDRAMC_SDCR_REF) clrbits_be32(&sdram->ctrl, SDRAMC_SDCR_CKE); /* * Initialize the PLL to generate the new system clock frequency. * The device must be put into LIMP mode to reprogram the PLL. */ /* Enter LIMP mode */ clock_limp(DEFAULT_LPD); #ifdef CONFIG_MCF5301x out_be32(&pll->pdr, PLL_PDR_OUTDIV1((BUSDIV / 3) - 1) | PLL_PDR_OUTDIV2(BUSDIV - 1) | PLL_PDR_OUTDIV3((BUSDIV / 2) - 1) | PLL_PDR_OUTDIV4(USBDIV - 1)); clrbits_be32(&pll->pcr, ~PLL_PCR_FBDIV_UNMASK); setbits_be32(&pll->pcr, PLL_PCR_FBDIV(mfd - 1)); #endif #ifdef CONFIG_MCF532x /* Reprogram PLL for desired fsys */ out_8(&pll->podr, PLL_PODR_CPUDIV(BUSDIV / 3) | PLL_PODR_BUSDIV(BUSDIV)); out_8(&pll->pfdr, mfd); #endif /* Exit LIMP mode */ clock_exit_limp(); /* Return the SDRAM to normal operation if it is in use. */ if (in_be32(&sdram->ctrl) & SDRAMC_SDCR_REF) setbits_be32(&sdram->ctrl, SDRAMC_SDCR_CKE); #ifdef CONFIG_MCF532x /* * software workaround for SDRAM opeartion after exiting LIMP * mode errata */ out_be32(sdram_workaround, CONFIG_SYS_SDRAM_BASE); #endif /* wait for DQS logic to relock */ for (i = 0; i < 0x200; i++) ; #endif /* !defined(CONFIG_MONITOR_IS_IN_RAM) */ return fout; } /* get_clocks() fills in gd->cpu_clock and gd->bus_clk */ int get_clocks(void) { gd->bus_clk = clock_pll(CONFIG_SYS_CLK / 1000, 0) * 1000; gd->cpu_clk = (gd->bus_clk * 3); #ifdef CONFIG_SYS_I2C_FSL gd->arch.i2c1_clk = gd->bus_clk; #endif return (0); }