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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 | /* * * Copyright (C) 2004-2007 Freescale Semiconductor, Inc. * TsiChung Liew (Tsi-Chung.Liew@freescale.com) * * See file CREDITS for list of people who contributed to this * project. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as * published by the Free Software Foundation; either version 2 of * the License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, * MA 02111-1307 USA */ #include <common.h> #include <asm/processor.h> #include <asm/immap.h> DECLARE_GLOBAL_DATA_PTR; /* * Low Power Divider specifications */ #define CLOCK_LPD_MIN (1 << 0) /* Divider (decoded) */ #define CLOCK_LPD_MAX (1 << 15) /* Divider (decoded) */ #define CLOCK_PLL_FVCO_MAX 540000000 #define CLOCK_PLL_FVCO_MIN 300000000 #define CLOCK_PLL_FSYS_MAX 266666666 #define CLOCK_PLL_FSYS_MIN 100000000 #define MHZ 1000000 void clock_enter_limp(int lpdiv) { volatile ccm_t *ccm = (volatile ccm_t *)MMAP_CCM; int i, j; /* Check bounds of divider */ if (lpdiv < CLOCK_LPD_MIN) lpdiv = CLOCK_LPD_MIN; if (lpdiv > CLOCK_LPD_MAX) lpdiv = CLOCK_LPD_MAX; /* Round divider down to nearest power of two */ for (i = 0, j = lpdiv; j != 1; j >>= 1, i++) ; /* Apply the divider to the system clock */ ccm->cdr = (ccm->cdr & 0xF0FF) | CCM_CDR_LPDIV(i); /* Enable Limp Mode */ ccm->misccr |= CCM_MISCCR_LIMP; } /* * brief Exit Limp mode * warning The PLL should be set and locked prior to exiting Limp mode */ void clock_exit_limp(void) { volatile ccm_t *ccm = (volatile ccm_t *)MMAP_CCM; volatile pll_t *pll = (volatile pll_t *)MMAP_PLL; /* Exit Limp mode */ ccm->misccr &= ~CCM_MISCCR_LIMP; /* Wait for the PLL to lock */ while (!(pll->psr & PLL_PSR_LOCK)) ; } /* * get_clocks() fills in gd->cpu_clock and gd->bus_clk */ int get_clocks(void) { volatile ccm_t *ccm = (volatile ccm_t *)MMAP_CCM; volatile pll_t *pll = (volatile pll_t *)MMAP_PLL; int vco, temp, pcrvalue, pfdr; u8 bootmode; bootmode = (ccm->ccr & 0x000C) >> 2; pcrvalue = pll->pcr & 0xFF0F0FFF; pfdr = pcrvalue >> 24; if (pfdr != 0x1E) { /* serial mode */ } else { /* Normal Mode */ vco = pfdr * CFG_INPUT_CLKSRC; gd->vco_clk = vco; } if ((ccm->ccr & CCM_MISCCR_LIMP) == CCM_MISCCR_LIMP) { /* Limp mode */ } else { gd->inp_clk = CFG_INPUT_CLKSRC; /* Input clock */ temp = (pll->pcr & PLL_PCR_OUTDIV1_MASK) + 1; gd->cpu_clk = vco / temp; /* cpu clock */ temp = ((pll->pcr & PLL_PCR_OUTDIV2_MASK) >> 4) + 1; gd->flb_clk = vco / temp; /* flexbus clock */ gd->bus_clk = gd->flb_clk; } return (0); } |