1 /* 2 * (C) Copyright 2003 3 * Texas Instruments <www.ti.com> 4 * 5 * (C) Copyright 2002 6 * Sysgo Real-Time Solutions, GmbH <www.elinos.com> 7 * Marius Groeger <mgroeger@sysgo.de> 8 * 9 * (C) Copyright 2002 10 * Sysgo Real-Time Solutions, GmbH <www.elinos.com> 11 * Alex Zuepke <azu@sysgo.de> 12 * 13 * (C) Copyright 2002-2004 14 * Gary Jennejohn, DENX Software Engineering, <garyj@denx.de> 15 * 16 * (C) Copyright 2004 17 * Philippe Robin, ARM Ltd. <philippe.robin@arm.com> 18 * 19 * SPDX-License-Identifier: GPL-2.0+ 20 */ 21 22 #include <common.h> 23 24 #define TIMER_ENABLE (1 << 7) 25 #define TIMER_MODE_MSK (1 << 6) 26 #define TIMER_MODE_FR (0 << 6) 27 #define TIMER_MODE_PD (1 << 6) 28 29 #define TIMER_INT_EN (1 << 5) 30 #define TIMER_PRS_MSK (3 << 2) 31 #define TIMER_PRS_8S (1 << 3) 32 #define TIMER_SIZE_MSK (1 << 2) 33 #define TIMER_ONE_SHT (1 << 0) 34 35 int timer_init (void) 36 { 37 ulong tmr_ctrl_val; 38 39 /* 1st disable the Timer */ 40 tmr_ctrl_val = *(volatile ulong *)(CONFIG_SYS_TIMERBASE + 8); 41 tmr_ctrl_val &= ~TIMER_ENABLE; 42 *(volatile ulong *)(CONFIG_SYS_TIMERBASE + 8) = tmr_ctrl_val; 43 44 /* 45 * The Timer Control Register has one Undefined/Shouldn't Use Bit 46 * So we should do read/modify/write Operation 47 */ 48 49 /* 50 * Timer Mode : Free Running 51 * Interrupt : Disabled 52 * Prescale : 8 Stage, Clk/256 53 * Tmr Siz : 16 Bit Counter 54 * Tmr in Wrapping Mode 55 */ 56 tmr_ctrl_val = *(volatile ulong *)(CONFIG_SYS_TIMERBASE + 8); 57 tmr_ctrl_val &= ~(TIMER_MODE_MSK | TIMER_INT_EN | TIMER_PRS_MSK | TIMER_SIZE_MSK | TIMER_ONE_SHT ); 58 tmr_ctrl_val |= (TIMER_ENABLE | TIMER_PRS_8S); 59 60 *(volatile ulong *)(CONFIG_SYS_TIMERBASE + 8) = tmr_ctrl_val; 61 62 return 0; 63 } 64 65