From c87581027994c148131b2f11aa75501f782ec19a Mon Sep 17 00:00:00 2001 From: TsiChungLiew Date: Mon, 14 Jan 2008 17:46:19 -0600 Subject: ColdFire: Add MCF5227x cpu and MCF52277EVB support-2 Signed-off-by: TsiChungLiew Signed-off by: John Rigby --- cpu/mcf5227x/speed.c | 120 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 120 insertions(+) create mode 100644 cpu/mcf5227x/speed.c (limited to 'cpu/mcf5227x/speed.c') diff --git a/cpu/mcf5227x/speed.c b/cpu/mcf5227x/speed.c new file mode 100644 index 0000000000..78c946f258 --- /dev/null +++ b/cpu/mcf5227x/speed.c @@ -0,0 +1,120 @@ +/* + * + * 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 +#include + +#include + +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); +} -- cgit v1.2.3