diff options
Diffstat (limited to 'arch/arm/plat-stmp3xxx/core.c')
-rw-r--r-- | arch/arm/plat-stmp3xxx/core.c | 128 |
1 files changed, 128 insertions, 0 deletions
diff --git a/arch/arm/plat-stmp3xxx/core.c b/arch/arm/plat-stmp3xxx/core.c new file mode 100644 index 00000000000..37b8a09148a --- /dev/null +++ b/arch/arm/plat-stmp3xxx/core.c @@ -0,0 +1,128 @@ +/* + * 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(); +} |