mirror of
				https://github.com/smaeul/u-boot.git
				synced 2025-10-31 03:58:17 +00:00 
			
		
		
		
	The patch add initial support for the Freescale i.MX51 processor (family arm cortex_a8). Signed-off-by: Stefano Babic <sbabic@denx.de> Signed-off-by: Fred Fan <fanyefeng@gmail.com>
		
			
				
	
	
		
			120 lines
		
	
	
		
			2.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			120 lines
		
	
	
		
			2.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
 | |
|  * (C) Copyright 2007
 | |
|  * Sascha Hauer, Pengutronix
 | |
|  *
 | |
|  * (C) Copyright 2009 Freescale Semiconductor, Inc.
 | |
|  *
 | |
|  * 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 <asm/arch/imx-regs.h>
 | |
| 
 | |
| /* General purpose timers registers */
 | |
| struct mxc_gpt {
 | |
| 	unsigned int control;
 | |
| 	unsigned int prescaler;
 | |
| 	unsigned int status;
 | |
| 	unsigned int nouse[6];
 | |
| 	unsigned int counter;
 | |
| };
 | |
| 
 | |
| static struct mxc_gpt *cur_gpt = (struct mxc_gpt *)GPT1_BASE_ADDR;
 | |
| 
 | |
| /* General purpose timers bitfields */
 | |
| #define GPTCR_SWR       (1<<15)	/* Software reset */
 | |
| #define GPTCR_FRR       (1<<9)	/* Freerun / restart */
 | |
| #define GPTCR_CLKSOURCE_32 (4<<6)	/* Clock source */
 | |
| #define GPTCR_TEN       (1)	/* Timer enable */
 | |
| 
 | |
| static ulong timestamp;
 | |
| static ulong lastinc;
 | |
| 
 | |
| int timer_init(void)
 | |
| {
 | |
| 	int i;
 | |
| 
 | |
| 	/* setup GP Timer 1 */
 | |
| 	__raw_writel(GPTCR_SWR, &cur_gpt->control);
 | |
| 
 | |
| 	/* We have no udelay by now */
 | |
| 	for (i = 0; i < 100; i++)
 | |
| 		__raw_writel(0, &cur_gpt->control);
 | |
| 
 | |
| 	__raw_writel(0, &cur_gpt->prescaler); /* 32Khz */
 | |
| 
 | |
| 	/* Freerun Mode, PERCLK1 input */
 | |
| 	i = __raw_readl(&cur_gpt->control);
 | |
| 	__raw_writel(i | GPTCR_CLKSOURCE_32 | GPTCR_TEN, &cur_gpt->control);
 | |
| 	reset_timer_masked();
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| void reset_timer(void)
 | |
| {
 | |
| 	reset_timer_masked();
 | |
| }
 | |
| 
 | |
| void reset_timer_masked(void)
 | |
| {
 | |
| 	ulong val = __raw_readl(&cur_gpt->counter);
 | |
| 	lastinc = val / (CONFIG_MX51_CLK32 / CONFIG_SYS_HZ);
 | |
| 	timestamp = 0;
 | |
| }
 | |
| 
 | |
| ulong get_timer_masked(void)
 | |
| {
 | |
| 	ulong val = __raw_readl(&cur_gpt->counter);
 | |
| 	val /= (CONFIG_MX51_CLK32 / CONFIG_SYS_HZ);
 | |
| 	if (val >= lastinc)
 | |
| 		timestamp += (val - lastinc);
 | |
| 	else
 | |
| 		timestamp += ((0xFFFFFFFF / (CONFIG_MX51_CLK32 / CONFIG_SYS_HZ))
 | |
| 				- lastinc) + val;
 | |
| 	lastinc = val;
 | |
| 	return val;
 | |
| }
 | |
| 
 | |
| ulong get_timer(ulong base)
 | |
| {
 | |
| 	return get_timer_masked() - base;
 | |
| }
 | |
| 
 | |
| void set_timer(ulong t)
 | |
| {
 | |
| 	timestamp = t;
 | |
| }
 | |
| 
 | |
| /* delay x useconds AND perserve advance timstamp value */
 | |
| void __udelay(unsigned long usec)
 | |
| {
 | |
| 	unsigned long now, start, tmo;
 | |
| 	tmo = usec * (CONFIG_MX51_CLK32 / 1000) / 1000;
 | |
| 
 | |
| 	if (!tmo)
 | |
| 		tmo = 1;
 | |
| 
 | |
| 	now = start = readl(&cur_gpt->counter);
 | |
| 
 | |
| 	while ((now - start) < tmo)
 | |
| 		now = readl(&cur_gpt->counter);
 | |
| 
 | |
| }
 |