dmitry pervushin | 5cccd37 | 2009-04-23 12:24:13 +0100 | [diff] [blame] | 1 | /* |
| 2 | * Freescale STMP37XX/STMP378X core routines |
| 3 | * |
| 4 | * Embedded Alley Solutions, Inc <source@embeddedalley.com> |
| 5 | * |
| 6 | * Copyright 2008 Freescale Semiconductor, Inc. All Rights Reserved. |
| 7 | * Copyright 2008 Embedded Alley Solutions, Inc All Rights Reserved. |
| 8 | */ |
| 9 | |
| 10 | /* |
| 11 | * The code contained herein is licensed under the GNU General Public |
| 12 | * License. You may obtain a copy of the GNU General Public License |
| 13 | * Version 2 or later at the following locations: |
| 14 | * |
| 15 | * http://www.opensource.org/licenses/gpl-license.html |
| 16 | * http://www.gnu.org/copyleft/gpl.html |
| 17 | */ |
| 18 | #include <linux/kernel.h> |
| 19 | #include <linux/init.h> |
| 20 | #include <linux/io.h> |
| 21 | |
| 22 | #include <mach/stmp3xxx.h> |
dmitry pervushin | 98f420b | 2009-05-31 13:32:11 +0100 | [diff] [blame] | 23 | #include <mach/platform.h> |
dmitry pervushin | 5cccd37 | 2009-04-23 12:24:13 +0100 | [diff] [blame] | 24 | #include <mach/dma.h> |
| 25 | #include <mach/regs-clkctrl.h> |
| 26 | |
| 27 | static int __stmp3xxx_reset_block(void __iomem *hwreg, int just_enable) |
| 28 | { |
| 29 | u32 c; |
| 30 | int timeout; |
| 31 | |
| 32 | /* the process of software reset of IP block is done |
| 33 | in several steps: |
| 34 | |
| 35 | - clear SFTRST and wait for block is enabled; |
| 36 | - clear clock gating (CLKGATE bit); |
| 37 | - set the SFTRST again and wait for block is in reset; |
| 38 | - clear SFTRST and wait for reset completion. |
| 39 | */ |
| 40 | c = __raw_readl(hwreg); |
| 41 | c &= ~(1<<31); /* clear SFTRST */ |
| 42 | __raw_writel(c, hwreg); |
| 43 | for (timeout = 1000000; timeout > 0; timeout--) |
| 44 | /* still in SFTRST state ? */ |
| 45 | if ((__raw_readl(hwreg) & (1<<31)) == 0) |
| 46 | break; |
| 47 | if (timeout <= 0) { |
| 48 | printk(KERN_ERR"%s(%p): timeout when enabling\n", |
| 49 | __func__, hwreg); |
| 50 | return -ETIME; |
| 51 | } |
| 52 | |
| 53 | c = __raw_readl(hwreg); |
| 54 | c &= ~(1<<30); /* clear CLKGATE */ |
| 55 | __raw_writel(c, hwreg); |
| 56 | |
| 57 | if (!just_enable) { |
| 58 | c = __raw_readl(hwreg); |
| 59 | c |= (1<<31); /* now again set SFTRST */ |
| 60 | __raw_writel(c, hwreg); |
| 61 | for (timeout = 1000000; timeout > 0; timeout--) |
| 62 | /* poll until CLKGATE set */ |
| 63 | if (__raw_readl(hwreg) & (1<<30)) |
| 64 | break; |
| 65 | if (timeout <= 0) { |
| 66 | printk(KERN_ERR"%s(%p): timeout when resetting\n", |
| 67 | __func__, hwreg); |
| 68 | return -ETIME; |
| 69 | } |
| 70 | |
| 71 | c = __raw_readl(hwreg); |
| 72 | c &= ~(1<<31); /* clear SFTRST */ |
| 73 | __raw_writel(c, hwreg); |
| 74 | for (timeout = 1000000; timeout > 0; timeout--) |
| 75 | /* still in SFTRST state ? */ |
| 76 | if ((__raw_readl(hwreg) & (1<<31)) == 0) |
| 77 | break; |
| 78 | if (timeout <= 0) { |
| 79 | printk(KERN_ERR"%s(%p): timeout when enabling " |
| 80 | "after reset\n", __func__, hwreg); |
| 81 | return -ETIME; |
| 82 | } |
| 83 | |
| 84 | c = __raw_readl(hwreg); |
| 85 | c &= ~(1<<30); /* clear CLKGATE */ |
| 86 | __raw_writel(c, hwreg); |
| 87 | } |
| 88 | for (timeout = 1000000; timeout > 0; timeout--) |
| 89 | /* still in SFTRST state ? */ |
| 90 | if ((__raw_readl(hwreg) & (1<<30)) == 0) |
| 91 | break; |
| 92 | |
| 93 | if (timeout <= 0) { |
| 94 | printk(KERN_ERR"%s(%p): timeout when unclockgating\n", |
| 95 | __func__, hwreg); |
| 96 | return -ETIME; |
| 97 | } |
| 98 | |
| 99 | return 0; |
| 100 | } |
| 101 | |
| 102 | int stmp3xxx_reset_block(void __iomem *hwreg, int just_enable) |
| 103 | { |
| 104 | int try = 10; |
| 105 | int r; |
| 106 | |
| 107 | while (try--) { |
| 108 | r = __stmp3xxx_reset_block(hwreg, just_enable); |
| 109 | if (!r) |
| 110 | break; |
| 111 | pr_debug("%s: try %d failed\n", __func__, 10 - try); |
| 112 | } |
| 113 | return r; |
| 114 | } |
| 115 | EXPORT_SYMBOL(stmp3xxx_reset_block); |
| 116 | |
| 117 | struct platform_device stmp3xxx_dbguart = { |
| 118 | .name = "stmp3xxx-dbguart", |
| 119 | .id = -1, |
| 120 | }; |
| 121 | |
| 122 | void __init stmp3xxx_init(void) |
| 123 | { |
| 124 | /* Turn off auto-slow and other tricks */ |
dmitry pervushin | 98f420b | 2009-05-31 13:32:11 +0100 | [diff] [blame] | 125 | stmp3xxx_clearl(0x7f00000, REGS_CLKCTRL_BASE + HW_CLKCTRL_HBUS); |
dmitry pervushin | 5cccd37 | 2009-04-23 12:24:13 +0100 | [diff] [blame] | 126 | |
| 127 | stmp3xxx_dma_init(); |
| 128 | } |