projects / people / ms / u-boot.git / blame
| Commit | Line | Data |
|---|---|---|
| 1dda0b1f WD |
1 | /* |
| 2 | * (C) Copyright 2000, 2001 | |
| 3 | * Wolfgang Denk, DENX Software Engineering, wd@denx.de. | |
| 4 | * | |
| 5 | * See file CREDITS for list of people who contributed to this | |
| 6 | * project. | |
| 7 | * | |
| 8 | * This program is free software; you can redistribute it and/or | |
| 9 | * modify it under the terms of the GNU General Public License as | |
| 10 | * published by the Free Software Foundation; either version 2 of | |
| 11 | * the License, or (at your option) any later version. | |
| 12 | * | |
| 13 | * This program is distributed in the hope that it will be useful, | |
| 14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
| 16 | * GNU General Public License for more details. | |
| 17 | * | |
| 18 | * You should have received a copy of the GNU General Public License | |
| 19 | * along with this program; if not, write to the Free Software | |
| 20 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, | |
| 21 | * MA 02111-1307 USA | |
| 22 | */ | |
| 23 | ||
| 24 | #include <common.h> | |
| 25 | ||
| 1dda0b1f WD |
26 | /* ------------------------------------------------------------------------- */ |
| 27 | ||
| 28 | /* | |
| 29 | * This function is intended for SHORT delays only. | |
| 30 | * It will overflow at around 10 seconds @ 400MHz, | |
| 31 | * or 20 seconds @ 200MHz. | |
| 32 | */ | |
| 33 | unsigned long usec2ticks(unsigned long usec) | |
| 34 | { | |
| 35 | ulong ticks; | |
| 36 | ||
| 37 | if (usec < 1000) { | |
| 38 | ticks = ((usec * (get_tbclk()/1000)) + 500) / 1000; | |
| 39 | } else { | |
| 40 | ticks = ((usec / 10) * (get_tbclk() / 100000)); | |
| 41 | } | |
| 42 | ||
| 43 | return (ticks); | |
| 44 | } | |
| 45 | ||
| 46 | /* ------------------------------------------------------------------------- */ | |
| 47 | ||
| 48 | /* | |
| 49 | * We implement the delay by converting the delay (the number of | |
| 50 | * microseconds to wait) into a number of time base ticks; then we | |
| 51 | * watch the time base until it has incremented by that amount. | |
| 52 | */ | |
| 3eb90bad | 53 | void __udelay(unsigned long usec) |
| 1dda0b1f | 54 | { |
| 3eb90bad IL |
55 | ulong ticks = usec2ticks (usec); |
| 56 | wait_ticks (ticks); | |
| 1dda0b1f WD |
57 | } |
| 58 | ||
| 59 | /* ------------------------------------------------------------------------- */ | |
| e4c09508 | 60 | #ifndef CONFIG_NAND_SPL |
| 1dda0b1f WD |
61 | unsigned long ticks2usec(unsigned long ticks) |
| 62 | { | |
| 63 | ulong tbclk = get_tbclk(); | |
| 64 | ||
| 65 | /* usec = ticks * 1000000 / tbclk | |
| 66 | * Multiplication would overflow at ~4.2e3 ticks, | |
| 67 | * so we break it up into | |
| 68 | * usec = ( ( ticks * 1000) / tbclk ) * 1000; | |
| 69 | */ | |
| 70 | ticks *= 1000L; | |
| 71 | ticks /= tbclk; | |
| 72 | ticks *= 1000L; | |
| 73 | ||
| 74 | return ((ulong)ticks); | |
| 75 | } | |
| e4c09508 | 76 | #endif |
| 1dda0b1f WD |
77 | /* ------------------------------------------------------------------------- */ |
| 78 | ||
| 79 | int init_timebase (void) | |
| 80 | { | |
| 0db5bca8 | 81 | #if defined(CONFIG_5xx) || defined(CONFIG_8xx) |
| 6d0f6bcf | 82 | volatile immap_t *immap = (immap_t *) CONFIG_SYS_IMMR; |
| 1dda0b1f WD |
83 | |
| 84 | /* unlock */ | |
| 85 | immap->im_sitk.sitk_tbk = KAPWR_KEY; | |
| 86 | #endif | |
| 87 | ||
| 88 | /* reset */ | |
| 89 | asm ("li 3,0 ; mttbu 3 ; mttbl 3 ;"); | |
| 90 | ||
| 0db5bca8 | 91 | #if defined(CONFIG_5xx) || defined(CONFIG_8xx) |
| 1dda0b1f WD |
92 | /* enable */ |
| 93 | immap->im_sit.sit_tbscr |= TBSCR_TBE; | |
| 94 | #endif | |
| 95 | return (0); | |
| 96 | } | |
| 97 | /* ------------------------------------------------------------------------- */ |