| Matthias Kaehlcke | cf3c142 | 2010-02-01 21:29:48 +0100 | [diff] [blame^] | 1 | /* |
| 2 | * PLL setup for Cirrus edb93xx boards |
| 3 | * |
| 4 | * Copyright (C) 2009 Matthias Kaehlcke <matthias@kaehlcke.net> |
| 5 | * |
| 6 | * Copyright (C) 2006 Dominic Rath <Dominic.Rath@gmx.de> |
| 7 | * |
| 8 | * See file CREDITS for list of people who contributed to this |
| 9 | * project. |
| 10 | * |
| 11 | * This program is free software; you can redistribute it and/or |
| 12 | * modify it under the terms of the GNU General Public License as |
| 13 | * published by the Free Software Foundation; either version 2 of |
| 14 | * the License, or (at your option) any later version. |
| 15 | * |
| 16 | * This program is distributed in the hope that it will be useful, |
| 17 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 18 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 19 | * GNU General Public License for more details. |
| 20 | * |
| 21 | * You should have received a copy of the GNU General Public License |
| 22 | * along with this program; if not, write to the Free Software |
| 23 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, |
| 24 | * MA 02111-1307 USA |
| 25 | */ |
| 26 | |
| 27 | #include <common.h> |
| 28 | #include <asm/io.h> |
| 29 | #include "pll_cfg.h" |
| 30 | #include "early_udelay.h" |
| 31 | |
| 32 | void pll_cfg(void) |
| 33 | { |
| 34 | struct syscon_regs *syscon = (struct syscon_regs *)SYSCON_BASE; |
| 35 | |
| 36 | /* setup PLL1 */ |
| 37 | writel(CLKSET1_VAL, &syscon->clkset1); |
| 38 | |
| 39 | /* |
| 40 | * flush the pipeline |
| 41 | * writing to CLKSET1 causes the EP93xx to enter standby for between |
| 42 | * 8 ms to 16 ms, until PLL1 stabilizes |
| 43 | */ |
| 44 | asm("nop"); |
| 45 | asm("nop"); |
| 46 | asm("nop"); |
| 47 | asm("nop"); |
| 48 | asm("nop"); |
| 49 | |
| 50 | /* setup PLL2 */ |
| 51 | writel(CLKSET2_VAL, &syscon->clkset2); |
| 52 | |
| 53 | /* |
| 54 | * the user's guide recommends to wait at least 1 ms for PLL2 to |
| 55 | * stabilize |
| 56 | */ |
| 57 | early_udelay(1000); |
| 58 | } |