1*a47a12beSStefan Roese /* 2*a47a12beSStefan Roese * (C) Copyright 2000, 2001 3*a47a12beSStefan Roese * Wolfgang Denk, DENX Software Engineering, wd@denx.de. 4*a47a12beSStefan Roese * 5*a47a12beSStefan Roese * See file CREDITS for list of people who contributed to this 6*a47a12beSStefan Roese * project. 7*a47a12beSStefan Roese * 8*a47a12beSStefan Roese * This program is free software; you can redistribute it and/or 9*a47a12beSStefan Roese * modify it under the terms of the GNU General Public License as 10*a47a12beSStefan Roese * published by the Free Software Foundation; either version 2 of 11*a47a12beSStefan Roese * the License, or (at your option) any later version. 12*a47a12beSStefan Roese * 13*a47a12beSStefan Roese * This program is distributed in the hope that it will be useful, 14*a47a12beSStefan Roese * but WITHOUT ANY WARRANTY; without even the implied warranty of 15*a47a12beSStefan Roese * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16*a47a12beSStefan Roese * GNU General Public License for more details. 17*a47a12beSStefan Roese * 18*a47a12beSStefan Roese * You should have received a copy of the GNU General Public License 19*a47a12beSStefan Roese * along with this program; if not, write to the Free Software 20*a47a12beSStefan Roese * Foundation, Inc., 59 Temple Place, Suite 330, Boston, 21*a47a12beSStefan Roese * MA 02111-1307 USA 22*a47a12beSStefan Roese */ 23*a47a12beSStefan Roese 24*a47a12beSStefan Roese #include <common.h> 25*a47a12beSStefan Roese 26*a47a12beSStefan Roese /* ------------------------------------------------------------------------- */ 27*a47a12beSStefan Roese 28*a47a12beSStefan Roese /* 29*a47a12beSStefan Roese * This function is intended for SHORT delays only. 30*a47a12beSStefan Roese * It will overflow at around 10 seconds @ 400MHz, 31*a47a12beSStefan Roese * or 20 seconds @ 200MHz. 32*a47a12beSStefan Roese */ 33*a47a12beSStefan Roese unsigned long usec2ticks(unsigned long usec) 34*a47a12beSStefan Roese { 35*a47a12beSStefan Roese ulong ticks; 36*a47a12beSStefan Roese 37*a47a12beSStefan Roese if (usec < 1000) { 38*a47a12beSStefan Roese ticks = ((usec * (get_tbclk()/1000)) + 500) / 1000; 39*a47a12beSStefan Roese } else { 40*a47a12beSStefan Roese ticks = ((usec / 10) * (get_tbclk() / 100000)); 41*a47a12beSStefan Roese } 42*a47a12beSStefan Roese 43*a47a12beSStefan Roese return (ticks); 44*a47a12beSStefan Roese } 45*a47a12beSStefan Roese 46*a47a12beSStefan Roese /* ------------------------------------------------------------------------- */ 47*a47a12beSStefan Roese 48*a47a12beSStefan Roese /* 49*a47a12beSStefan Roese * We implement the delay by converting the delay (the number of 50*a47a12beSStefan Roese * microseconds to wait) into a number of time base ticks; then we 51*a47a12beSStefan Roese * watch the time base until it has incremented by that amount. 52*a47a12beSStefan Roese */ 53*a47a12beSStefan Roese void __udelay(unsigned long usec) 54*a47a12beSStefan Roese { 55*a47a12beSStefan Roese ulong ticks = usec2ticks (usec); 56*a47a12beSStefan Roese wait_ticks (ticks); 57*a47a12beSStefan Roese } 58*a47a12beSStefan Roese 59*a47a12beSStefan Roese /* ------------------------------------------------------------------------- */ 60*a47a12beSStefan Roese #ifndef CONFIG_NAND_SPL 61*a47a12beSStefan Roese unsigned long ticks2usec(unsigned long ticks) 62*a47a12beSStefan Roese { 63*a47a12beSStefan Roese ulong tbclk = get_tbclk(); 64*a47a12beSStefan Roese 65*a47a12beSStefan Roese /* usec = ticks * 1000000 / tbclk 66*a47a12beSStefan Roese * Multiplication would overflow at ~4.2e3 ticks, 67*a47a12beSStefan Roese * so we break it up into 68*a47a12beSStefan Roese * usec = ( ( ticks * 1000) / tbclk ) * 1000; 69*a47a12beSStefan Roese */ 70*a47a12beSStefan Roese ticks *= 1000L; 71*a47a12beSStefan Roese ticks /= tbclk; 72*a47a12beSStefan Roese ticks *= 1000L; 73*a47a12beSStefan Roese 74*a47a12beSStefan Roese return ((ulong)ticks); 75*a47a12beSStefan Roese } 76*a47a12beSStefan Roese #endif 77*a47a12beSStefan Roese /* ------------------------------------------------------------------------- */ 78*a47a12beSStefan Roese 79*a47a12beSStefan Roese int init_timebase (void) 80*a47a12beSStefan Roese { 81*a47a12beSStefan Roese #if defined(CONFIG_5xx) || defined(CONFIG_8xx) 82*a47a12beSStefan Roese volatile immap_t *immap = (immap_t *) CONFIG_SYS_IMMR; 83*a47a12beSStefan Roese 84*a47a12beSStefan Roese /* unlock */ 85*a47a12beSStefan Roese immap->im_sitk.sitk_tbk = KAPWR_KEY; 86*a47a12beSStefan Roese #endif 87*a47a12beSStefan Roese 88*a47a12beSStefan Roese /* reset */ 89*a47a12beSStefan Roese asm ("li 3,0 ; mttbu 3 ; mttbl 3 ;"); 90*a47a12beSStefan Roese 91*a47a12beSStefan Roese #if defined(CONFIG_5xx) || defined(CONFIG_8xx) 92*a47a12beSStefan Roese /* enable */ 93*a47a12beSStefan Roese immap->im_sit.sit_tbscr |= TBSCR_TBE; 94*a47a12beSStefan Roese #endif 95*a47a12beSStefan Roese return (0); 96*a47a12beSStefan Roese } 97*a47a12beSStefan Roese /* ------------------------------------------------------------------------- */ 98