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Diffstat (limited to 'arch/ppc/cpu/mpc8xx/speed.c')
| -rw-r--r-- | arch/ppc/cpu/mpc8xx/speed.c | 416 |
1 files changed, 0 insertions, 416 deletions
diff --git a/arch/ppc/cpu/mpc8xx/speed.c b/arch/ppc/cpu/mpc8xx/speed.c deleted file mode 100644 index f309f29..0000000 --- a/arch/ppc/cpu/mpc8xx/speed.c +++ /dev/null @@ -1,416 +0,0 @@ -/* - * (C) Copyright 2000-2004 - * Wolfgang Denk, DENX Software Engineering, wd@denx.de. - * - * 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 <mpc8xx.h> -#include <asm/processor.h> - -DECLARE_GLOBAL_DATA_PTR; - -#if !defined(CONFIG_8xx_CPUCLK_DEFAULT) || defined(CONFIG_SYS_MEASURE_CPUCLK) || defined(DEBUG) - -#define PITC_SHIFT 16 -#define PITR_SHIFT 16 -/* pitc values to time for 58/8192 seconds (about 70.8 milliseconds) */ -#define SPEED_PIT_COUNTS 58 -#define SPEED_PITC ((SPEED_PIT_COUNTS - 1) << PITC_SHIFT) -#define SPEED_PITC_INIT ((SPEED_PIT_COUNTS + 1) << PITC_SHIFT) - -/* Access functions for the Machine State Register */ -static __inline__ unsigned long get_msr(void) -{ - unsigned long msr; - - asm volatile("mfmsr %0" : "=r" (msr) :); - return msr; -} - -static __inline__ void set_msr(unsigned long msr) -{ - asm volatile("mtmsr %0" : : "r" (msr)); -} - -/* ------------------------------------------------------------------------- */ - -/* - * Measure CPU clock speed (core clock GCLK1, GCLK2), - * also determine bus clock speed (checking bus divider factor) - * - * (Approx. GCLK frequency in Hz) - * - * Initializes timer 2 and PIT, but disables them before return. - * [Use timer 2, because MPC823 CPUs mask 0.x do not have timers 3 and 4] - * - * When measuring the CPU clock against the PIT, we count cpu clocks - * for 58/8192 seconds with a prescale divide by 177 for the cpu clock. - * These strange values for the timing interval and prescaling are used - * because the formula for the CPU clock is: - * - * CPU clock = count * (177 * (8192 / 58)) - * - * = count * 24999.7241 - * - * which is very close to - * - * = count * 25000 - * - * Since the count gives the CPU clock divided by 25000, we can get - * the CPU clock rounded to the nearest 0.1 MHz by - * - * CPU clock = ((count + 2) / 4) * 100000; - * - * The rounding is important since the measurement is sometimes going - * to be high or low by 0.025 MHz, depending on exactly how the clocks - * and counters interact. By rounding we get the exact answer for any - * CPU clock that is an even multiple of 0.1 MHz. - */ - -unsigned long measure_gclk(void) -{ - volatile immap_t *immr = (immap_t *) CONFIG_SYS_IMMR; - volatile cpmtimer8xx_t *timerp = &immr->im_cpmtimer; - ulong timer2_val; - ulong msr_val; - -#ifdef CONFIG_SYS_8XX_XIN - /* dont use OSCM, only use EXTCLK/512 */ - immr->im_clkrst.car_sccr |= SCCR_RTSEL | SCCR_RTDIV; -#else - immr->im_clkrst.car_sccr &= ~(SCCR_RTSEL | SCCR_RTDIV); -#endif - - /* Reset + Stop Timer 2, no cascading - */ - timerp->cpmt_tgcr &= ~(TGCR_CAS2 | TGCR_RST2); - - /* Keep stopped, halt in debug mode - */ - timerp->cpmt_tgcr |= (TGCR_FRZ2 | TGCR_STP2); - - /* Timer 2 setup: - * Output ref. interrupt disable, int. clock - * Prescale by 177. Note that prescaler divides by value + 1 - * so we must subtract 1 here. - */ - timerp->cpmt_tmr2 = ((177 - 1) << TMR_PS_SHIFT) | TMR_ICLK_IN_GEN; - - timerp->cpmt_tcn2 = 0; /* reset state */ - timerp->cpmt_tgcr |= TGCR_RST2; /* enable timer 2 */ - - /* - * PIT setup: - * - * We want to time for SPEED_PITC_COUNTS counts (of 8192 Hz), - * so the count value would be SPEED_PITC_COUNTS - 1. - * But there would be an uncertainty in the start time of 1/4 - * count since when we enable the PIT the count is not - * synchronized to the 32768 Hz oscillator. The trick here is - * to start the count higher and wait until the PIT count - * changes to the required value before starting timer 2. - * - * One count high should be enough, but occasionally the start - * is off by 1 or 2 counts of 32768 Hz. With the start value - * set two counts high it seems very reliable. - */ - - immr->im_sitk.sitk_pitck = KAPWR_KEY; /* PIT initialization */ - immr->im_sit.sit_pitc = SPEED_PITC_INIT; - - immr->im_sitk.sitk_piscrk = KAPWR_KEY; - immr->im_sit.sit_piscr = CONFIG_SYS_PISCR; - - /* - * Start measurement - disable interrupts, just in case - */ - msr_val = get_msr (); - set_msr (msr_val & ~MSR_EE); - - immr->im_sit.sit_piscr |= PISCR_PTE; - - /* spin until get exact count when we want to start */ - while (immr->im_sit.sit_pitr > SPEED_PITC); - - timerp->cpmt_tgcr &= ~TGCR_STP2; /* Start Timer 2 */ - while ((immr->im_sit.sit_piscr & PISCR_PS) == 0); - timerp->cpmt_tgcr |= TGCR_STP2; /* Stop Timer 2 */ - - /* re-enable external interrupts if they were on */ - set_msr (msr_val); - - /* Disable timer and PIT - */ - timer2_val = timerp->cpmt_tcn2; /* save before reset timer */ - - timerp->cpmt_tgcr &= ~(TGCR_RST2 | TGCR_FRZ2 | TGCR_STP2); - immr->im_sit.sit_piscr &= ~PISCR_PTE; - -#if defined(CONFIG_SYS_8XX_XIN) - /* not using OSCM, using XIN, so scale appropriately */ - return (((timer2_val + 2) / 4) * (CONFIG_SYS_8XX_XIN/512))/8192 * 100000L; -#else - return ((timer2_val + 2) / 4) * 100000L; /* convert to Hz */ -#endif -} - -#endif - -void get_brgclk(uint sccr) -{ - uint divider = 0; - - switch((sccr&SCCR_DFBRG11)>>11){ - case 0: - divider = 1; - break; - case 1: - divider = 4; - break; - case 2: - divider = 16; - break; - case 3: - divider = 64; - break; - } - gd->brg_clk = gd->cpu_clk/divider; -} - -#if !defined(CONFIG_8xx_CPUCLK_DEFAULT) - -/* - * get_clocks() fills in gd->cpu_clock depending on CONFIG_8xx_GCLK_FREQ - * or (if it is not defined) measure_gclk() (which uses the ref clock) - * from above. - */ -int get_clocks (void) -{ - uint immr = get_immr (0); /* Return full IMMR contents */ - volatile immap_t *immap = (immap_t *) (immr & 0xFFFF0000); - uint sccr = immap->im_clkrst.car_sccr; - /* - * If for some reason measuring the gclk frequency won't - * work, we return the hardwired value. - * (For example, the cogent CMA286-60 CPU module has no - * separate oscillator for PITRTCLK) - */ -#if defined(CONFIG_8xx_GCLK_FREQ) - gd->cpu_clk = CONFIG_8xx_GCLK_FREQ; -#elif defined(CONFIG_8xx_OSCLK) -#define PLPRCR_val(a) ((pll & PLPRCR_ ## a ## _MSK) >> PLPRCR_ ## a ## _SHIFT) - uint pll = immap->im_clkrst.car_plprcr; - uint clk; - - if ((immr & 0x0FFF) >= MPC8xx_NEW_CLK) { /* MPC866/87x/88x series */ - clk = ((CONFIG_8xx_OSCLK / (PLPRCR_val(PDF)+1)) * - (PLPRCR_val(MFI) + PLPRCR_val(MFN) / (PLPRCR_val(MFD)+1))) / - (1<<PLPRCR_val(S)); - } else { - clk = CONFIG_8xx_OSCLK * (PLPRCR_val(MF)+1); - } - if (pll & PLPRCR_CSRC) { /* Low frequency division factor is used */ - gd->cpu_clk = clk / (2 << ((sccr >> 8) & 7)); - } else { /* High frequency division factor is used */ - gd->cpu_clk = clk / (1 << ((sccr >> 5) & 7)); - } -#else - gd->cpu_clk = measure_gclk(); -#endif /* CONFIG_8xx_GCLK_FREQ */ - - if ((sccr & SCCR_EBDF11) == 0) { - /* No Bus Divider active */ - gd->bus_clk = gd->cpu_clk; - } else { - /* The MPC8xx has only one BDF: half clock speed */ - gd->bus_clk = gd->cpu_clk / 2; - } - - get_brgclk(sccr); - - return (0); -} - -#else /* CONFIG_8xx_CPUCLK_DEFAULT defined, use dynamic clock setting */ - -static long init_pll_866 (long clk); - -/* This function sets up PLL (init_pll_866() is called) and - * fills gd->cpu_clk and gd->bus_clk according to the environment - * variable 'cpuclk' or to CONFIG_8xx_CPUCLK_DEFAULT (if 'cpuclk' - * contains invalid value). - * This functions requires an MPC866 or newer series CPU. - */ -int get_clocks_866 (void) -{ - volatile immap_t *immr = (immap_t *) CONFIG_SYS_IMMR; - char tmp[64]; - long cpuclk = 0; - long sccr_reg; - - if (getenv_r ("cpuclk", tmp, sizeof (tmp)) > 0) - cpuclk = simple_strtoul (tmp, NULL, 10) * 1000000; - - if ((CONFIG_SYS_8xx_CPUCLK_MIN > cpuclk) || (CONFIG_SYS_8xx_CPUCLK_MAX < cpuclk)) - cpuclk = CONFIG_8xx_CPUCLK_DEFAULT; - - gd->cpu_clk = init_pll_866 (cpuclk); -#if defined(CONFIG_SYS_MEASURE_CPUCLK) - gd->cpu_clk = measure_gclk (); -#endif - - get_brgclk(immr->im_clkrst.car_sccr); - - /* if cpu clock <= 66 MHz then set bus division factor to 1, - * otherwise set it to 2 - */ - sccr_reg = immr->im_clkrst.car_sccr; - sccr_reg &= ~SCCR_EBDF11; - - if (gd->cpu_clk <= 66000000) { - sccr_reg |= SCCR_EBDF00; /* bus division factor = 1 */ - gd->bus_clk = gd->cpu_clk; - } else { - sccr_reg |= SCCR_EBDF01; /* bus division factor = 2 */ - gd->bus_clk = gd->cpu_clk / 2; - } - immr->im_clkrst.car_sccr = sccr_reg; - - return (0); -} - -/* Adjust sdram refresh rate to actual CPU clock. - */ -int sdram_adjust_866 (void) -{ - volatile immap_t *immr = (immap_t *) CONFIG_SYS_IMMR; - long mamr; - - mamr = immr->im_memctl.memc_mamr; - mamr &= ~MAMR_PTA_MSK; - mamr |= ((gd->cpu_clk / CONFIG_SYS_PTA_PER_CLK) << MAMR_PTA_SHIFT); - immr->im_memctl.memc_mamr = mamr; - - return (0); -} - -/* Configure PLL for MPC866/859/885 CPU series - * PLL multiplication factor is set to the value nearest to the desired clk, - * assuming a oscclk of 10 MHz. - */ -static long init_pll_866 (long clk) -{ - extern void plprcr_write_866 (long); - - volatile immap_t *immr = (immap_t *) CONFIG_SYS_IMMR; - long n, plprcr; - char mfi, mfn, mfd, s, pdf; - long step_mfi, step_mfn; - - if (clk < 20000000) { - clk *= 2; - pdf = 1; - } else { - pdf = 0; - } - - if (clk < 40000000) { - s = 2; - step_mfi = CONFIG_8xx_OSCLK / 4; - mfd = 7; - step_mfn = CONFIG_8xx_OSCLK / 30; - } else if (clk < 80000000) { - s = 1; - step_mfi = CONFIG_8xx_OSCLK / 2; - mfd = 14; - step_mfn = CONFIG_8xx_OSCLK / 30; - } else { - s = 0; - step_mfi = CONFIG_8xx_OSCLK; - mfd = 29; - step_mfn = CONFIG_8xx_OSCLK / 30; - } - - /* Calculate integer part of multiplication factor - */ - n = clk / step_mfi; - mfi = (char)n; - - /* Calculate numerator of fractional part of multiplication factor - */ - n = clk - (n * step_mfi); - mfn = (char)(n / step_mfn); - - /* Calculate effective clk - */ - n = ((mfi * step_mfi) + (mfn * step_mfn)) / (pdf + 1); - - immr->im_clkrstk.cark_plprcrk = KAPWR_KEY; - - plprcr = (immr->im_clkrst.car_plprcr & ~(PLPRCR_MFN_MSK - | PLPRCR_MFD_MSK | PLPRCR_S_MSK - | PLPRCR_MFI_MSK | PLPRCR_DBRMO - | PLPRCR_PDF_MSK)) - | (mfn << PLPRCR_MFN_SHIFT) - | (mfd << PLPRCR_MFD_SHIFT) - | (s << PLPRCR_S_SHIFT) - | (mfi << PLPRCR_MFI_SHIFT) - | (pdf << PLPRCR_PDF_SHIFT); - - if( (mfn > 0) && ((mfd / mfn) > 10) ) - plprcr |= PLPRCR_DBRMO; - - plprcr_write_866 (plprcr); /* set value using SIU4/9 workaround */ - immr->im_clkrstk.cark_plprcrk = 0x00000000; - - return (n); -} - -#endif /* CONFIG_8xx_CPUCLK_DEFAULT */ - -#if defined(CONFIG_TQM8xxL) && !defined(CONFIG_TQM866M) \ - && !defined(CONFIG_TQM885D) -/* - * Adjust sdram refresh rate to actual CPU clock - * and set timebase source according to actual CPU clock - */ -int adjust_sdram_tbs_8xx (void) -{ - volatile immap_t *immr = (immap_t *) CONFIG_SYS_IMMR; - long mamr; - long sccr; - - mamr = immr->im_memctl.memc_mamr; - mamr &= ~MAMR_PTA_MSK; - mamr |= ((gd->cpu_clk / CONFIG_SYS_PTA_PER_CLK) << MAMR_PTA_SHIFT); - immr->im_memctl.memc_mamr = mamr; - - if (gd->cpu_clk < 67000000) { - sccr = immr->im_clkrst.car_sccr; - sccr |= SCCR_TBS; - immr->im_clkrst.car_sccr = sccr; - } - - return (0); -} -#endif /* CONFIG_TQM8xxL/M, !TQM866M, !TQM885D */ - -/* ------------------------------------------------------------------------- */ |