/* * PLL setup for Cirrus edb93xx boards * * Copyright (C) 2009 Matthias Kaehlcke * * Copyright (C) 2006 Dominic Rath * * 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. * */ #include #include #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); }