/*
* Freescale STMP37XX/STMP378X core routines
*
* Embedded Alley Solutions, Inc <source@embeddedalley.com>
*
* Copyright 2008 Freescale Semiconductor, Inc. All Rights Reserved.
* Copyright 2008 Embedded Alley Solutions, Inc All Rights Reserved.
*/
/*
* The code contained herein is licensed under the GNU General Public
* License. You may obtain a copy of the GNU General Public License
* Version 2 or later at the following locations:
*
* http://www.opensource.org/licenses/gpl-license.html
* http://www.gnu.org/copyleft/gpl.html
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/io.h>
#include <mach/stmp3xxx.h>
#include <mach/platform.h>
#include <mach/dma.h>
#include <mach/regs-clkctrl.h>
static int __stmp3xxx_reset_block(void __iomem *hwreg, int just_enable)
{
u32 c;
int timeout;
/* the process of software reset of IP block is done
in several steps:
- clear SFTRST and wait for block is enabled;
- clear clock gating (CLKGATE bit);
- set the SFTRST again and wait for block is in reset;
- clear SFTRST and wait for reset completion.
*/
c = __raw_readl(hwreg);
c &= ~(1<<31); /* clear SFTRST */
__raw_writel(c, hwreg);
for (timeout = 1000000; timeout > 0; timeout--)
/* still in SFTRST state ? */
if ((__raw_readl(hwreg) & (1<<31)) == 0)
break;
if (timeout <= 0) {
printk(KERN_ERR"%s(%p): timeout when enabling\n",
__func__, hwreg);
return -ETIME;
}
c = __raw_readl(hwreg);
c &= ~(1<<30); /* clear CLKGATE */
__raw_writel(c, hwreg);
if (!just_enable) {
c = __raw_readl(hwreg);
c |= (1<<31); /* now again set SFTRST */
__raw_writel(c, hwreg);
for (timeout = 1000000; timeout > 0; timeout--)
/* poll until CLKGATE set */
if (__raw_readl(hwreg) & (1<<30))
break;
if (timeout <= 0) {
printk(KERN_ERR"%s(%p): timeout when resetting\n",
__func__, hwreg);
return -ETIME;
}
c = __raw_readl(hwreg);
c &= ~(1<<31); /* clear SFTRST */
__raw_writel(c, hwreg);
for (timeout = 1000000; timeout > 0; timeout--)
/* still in SFTRST state ? */
if ((__raw_readl(hwreg) & (1<<31)) == 0)
break;
if (timeout <= 0) {
printk(KERN_ERR"%s(%p): timeout when enabling "
"after reset\n", __func__, hwreg);
return -ETIME;
}
c = __raw_readl(hwreg);
c &= ~(1<<30); /* clear CLKGATE */
__raw_writel(c, hwreg);
}
for (timeout = 1000000; timeout > 0; timeout--)
/* still in SFTRST state ? */
if ((__raw_readl(hwreg) & (1<<30)) == 0)
break;
if (timeout <= 0) {
printk(KERN_ERR"%s(%p): timeout when unclockgating\n",
__func__, hwreg);
return -ETIME;
}
return 0;
}
int stmp3xxx_reset_block(void __iomem *hwreg, int just_enable)
{
int try = 10;
int r;
while (try--) {
r = __stmp3xxx_reset_block(hwreg, just_enable);
if (!r)
break;
pr_debug("%s: try %d failed\n", __func__, 10 - try);
}
return r;
}
EXPORT_SYMBOL(stmp3xxx_reset_block);
struct platform_device stmp3xxx_dbguart = {
.name = "stmp3xxx-dbguart",
.id = -1,
};
void __init stmp3xxx_init(void)
{
/* Turn off auto-slow and other tricks */
stmp3xxx_clearl(0x7f00000, REGS_CLKCTRL_BASE + HW_CLKCTRL_HBUS);
stmp3xxx_dma_init();
}
