diff options
Diffstat (limited to 'board/edb93xx/pll_cfg.c')
| -rw-r--r-- | board/edb93xx/pll_cfg.c | 58 |
1 files changed, 58 insertions, 0 deletions
diff --git a/board/edb93xx/pll_cfg.c b/board/edb93xx/pll_cfg.c new file mode 100644 index 0000000..a687af0 --- /dev/null +++ b/board/edb93xx/pll_cfg.c @@ -0,0 +1,58 @@ +/* + * PLL setup for Cirrus edb93xx boards + * + * Copyright (C) 2009 Matthias Kaehlcke <matthias@kaehlcke.net> + * + * Copyright (C) 2006 Dominic Rath <Dominic.Rath@gmx.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 <asm/io.h> +#include "pll_cfg.h" +#include "early_udelay.h" + +void pll_cfg(void) +{ + struct syscon_regs *syscon = (struct syscon_regs *)SYSCON_BASE; + + /* setup PLL1 */ + writel(CLKSET1_VAL, &syscon->clkset1); + + /* + * flush the pipeline + * writing to CLKSET1 causes the EP93xx to enter standby for between + * 8 ms to 16 ms, until PLL1 stabilizes + */ + asm("nop"); + asm("nop"); + asm("nop"); + asm("nop"); + asm("nop"); + + /* setup PLL2 */ + writel(CLKSET2_VAL, &syscon->clkset2); + + /* + * the user's guide recommends to wait at least 1 ms for PLL2 to + * stabilize + */ + early_udelay(1000); +} |