1/* 2 * OMAP4 CM module functions 3 * 4 * Copyright (C) 2009 Nokia Corporation 5 * Paul Walmsley 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License version 2 as 9 * published by the Free Software Foundation. 10 */ 11 12#include <linux/kernel.h> 13#include <linux/module.h> 14#include <linux/types.h> 15#include <linux/delay.h> 16#include <linux/spinlock.h> 17#include <linux/list.h> 18#include <linux/errno.h> 19#include <linux/err.h> 20#include <linux/io.h> 21 22#include <asm/atomic.h> 23 24#include <plat/common.h> 25 26#include "cm.h" 27#include "cm-regbits-44xx.h" 28 29/** 30 * omap4_cm_wait_module_ready - wait for a module to be in 'func' state 31 * @clkctrl_reg: CLKCTRL module address 32 * 33 * Wait for the module IDLEST to be functional. If the idle state is in any 34 * the non functional state (trans, idle or disabled), module and thus the 35 * sysconfig cannot be accessed and will probably lead to an "imprecise 36 * external abort" 37 * 38 * Module idle state: 39 * 0x0 func: Module is fully functional, including OCP 40 * 0x1 trans: Module is performing transition: wakeup, or sleep, or sleep 41 * abortion 42 * 0x2 idle: Module is in Idle mode (only OCP part). It is functional if 43 * using separate functional clock 44 * 0x3 disabled: Module is disabled and cannot be accessed 45 * 46 * TODO: Need to handle module accessible in idle state 47 */ 48int omap4_cm_wait_module_ready(void __iomem *clkctrl_reg) 49{ 50 int i = 0; 51 52 if (!clkctrl_reg) 53 return 0; 54 55 omap_test_timeout(((__raw_readl(clkctrl_reg) & 56 OMAP4430_IDLEST_MASK) == 0), 57 MAX_MODULE_READY_TIME, i); 58 59 return (i < MAX_MODULE_READY_TIME) ? 0 : -EBUSY; 60} 61