arch/arm/mach-pnx4008/sleep.S

   1 /*
   2  * linux/arch/arm/mach-pnx4008/sleep.S
   3  *
   4  * PNX4008 support for STOP mode and SDRAM self-refresh
   5  *
   6  * Authors: Dmitry Chigirev, Vitaly Wool <source@mvista.com>
   7  *
   8  * 2005 (c) MontaVista Software, Inc. This file is licensed under
   9  * the terms of the GNU General Public License version 2. This program
  10  * is licensed "as is" without any warranty of any kind, whether express
  11  * or implied.
  12  */
  13
  14 #include <linux/config.h>
  15 #include <linux/linkage.h>
  16 #include <asm/assembler.h>
  17 #include <asm/hardware.h>
  18
  19 #define PWRMAN_VA_BASE IO_ADDRESS(PNX4008_PWRMAN_BASE)
  20 #define PWR_CTRL_REG_OFFS 0x44
  21
  22 #define SDRAM_CFG_VA_BASE IO_ADDRESS(PNX4008_SDRAM_CFG_BASE)
  23 #define MPMC_STATUS_REG_OFFS 0x4
  24
  25                 .text
  26
  27 ENTRY(pnx4008_cpu_suspend)
  28         @this function should be entered in Direct run mode.
  29
  30         @ save registers on stack
  31         stmfd   sp!, {r0 - r6, lr}
  32
  33         @ setup Power Manager base address in r4
  34         @ and put it's value in r5
  35         mov     r4, #(PWRMAN_VA_BASE & 0xff000000)
  36         orr     r4, r4, #(PWRMAN_VA_BASE & 0x00ff0000)
  37         orr     r4, r4, #(PWRMAN_VA_BASE & 0x0000ff00)
  38         orr     r4, r4, #(PWRMAN_VA_BASE & 0x000000ff)
  39         ldr     r5, [r4, #PWR_CTRL_REG_OFFS]
  40
  41         @ setup SDRAM controller base address in r2
  42         @ and put it's value in r3
  43         mov     r2, #(SDRAM_CFG_VA_BASE & 0xff000000)
  44         orr     r2, r2, #(SDRAM_CFG_VA_BASE & 0x00ff0000)
  45         orr     r2, r2, #(SDRAM_CFG_VA_BASE & 0x0000ff00)
  46         orr     r2, r2, #(SDRAM_CFG_VA_BASE & 0x000000ff)
  47         ldr     r3, [r2, #MPMC_STATUS_REG_OFFS] @extra read - HW bug workaround
  48
  49         @ clear SDRAM self-refresh bit latch
  50         and     r5, r5, #(~(1 << 8))
  51         @ clear SDRAM self-refresh bit
  52         and     r5, r5, #(~(1 << 9))
  53         str     r5, [r4, #PWR_CTRL_REG_OFFS]
  54
  55         @ do save current bit settings in r1
  56         mov     r1, r5
  57
  58         @ set SDRAM self-refresh bit
  59         orr     r5, r5, #(1 << 9)
  60         str     r5, [r4, #PWR_CTRL_REG_OFFS]
  61
  62         @ set SDRAM self-refresh bit latch
  63         orr     r5, r5, #(1 << 8)
  64         str     r5, [r4, #PWR_CTRL_REG_OFFS]
  65
  66         @ clear SDRAM self-refresh bit latch
  67         and     r5, r5, #(~(1 << 8))
  68         str     r5, [r4, #PWR_CTRL_REG_OFFS]
  69
  70         @ clear SDRAM self-refresh bit
  71         and     r5, r5, #(~(1 << 9))
  72         str     r5, [r4, #PWR_CTRL_REG_OFFS]
  73
  74         @ wait for SDRAM to get into self-refresh mode
  75 2:      ldr     r3, [r2, #MPMC_STATUS_REG_OFFS]
  76         tst     r3, #(1 << 2)
  77         beq     2b
  78
  79         @ to prepare SDRAM to get out of self-refresh mode after wakeup
  80         orr     r5, r5, #(1 << 7)
  81         str     r5, [r4, #PWR_CTRL_REG_OFFS]
  82
  83         @ do enter stop mode
  84         orr     r5, r5, #(1 << 0)
  85         str     r5, [r4, #PWR_CTRL_REG_OFFS]
  86         nop
  87         nop
  88         nop
  89         nop
  90         nop
  91         nop
  92         nop
  93         nop
  94         nop
  95
  96         @ sleeping now...
  97
  98         @ coming out of STOP mode into Direct Run mode
  99         @ clear STOP mode and SDRAM self-refresh bits
 100         str     r1, [r4, #PWR_CTRL_REG_OFFS]
 101
 102         @ wait for SDRAM to get out self-refresh mode
 103 3:      ldr     r3, [r2, #MPMC_STATUS_REG_OFFS]
 104         tst     r3, #5
 105         bne     3b
 106
 107         @ restore regs and return
 108         ldmfd   sp!, {r0 - r6, pc}
 109
 110 ENTRY(pnx4008_cpu_suspend_sz)
 111         .word   . - pnx4008_cpu_suspend
 112
 113 ENTRY(pnx4008_cpu_standby)
 114         @ save registers on stack
 115         stmfd   sp!, {r0 - r6, lr}
 116
 117         @ setup Power Manager base address in r4
 118         @ and put it's value in r5
 119         mov     r4, #(PWRMAN_VA_BASE & 0xff000000)
 120         orr     r4, r4, #(PWRMAN_VA_BASE & 0x00ff0000)
 121         orr     r4, r4, #(PWRMAN_VA_BASE & 0x0000ff00)
 122         orr     r4, r4, #(PWRMAN_VA_BASE & 0x000000ff)
 123         ldr     r5, [r4, #PWR_CTRL_REG_OFFS]
 124
 125         @ setup SDRAM controller base address in r2
 126         @ and put it's value in r3
 127         mov     r2, #(SDRAM_CFG_VA_BASE & 0xff000000)
 128         orr     r2, r2, #(SDRAM_CFG_VA_BASE & 0x00ff0000)
 129         orr     r2, r2, #(SDRAM_CFG_VA_BASE & 0x0000ff00)
 130         orr     r2, r2, #(SDRAM_CFG_VA_BASE & 0x000000ff)
 131         ldr     r3, [r2, #MPMC_STATUS_REG_OFFS] @extra read - HW bug workaround
 132
 133         @ clear SDRAM self-refresh bit latch
 134         and     r5, r5, #(~(1 << 8))
 135         @ clear SDRAM self-refresh bit
 136         and     r5, r5, #(~(1 << 9))
 137         str     r5, [r4, #PWR_CTRL_REG_OFFS]
 138
 139         @ do save current bit settings in r1
 140         mov     r1, r5
 141
 142         @ set SDRAM self-refresh bit
 143         orr     r5, r5, #(1 << 9)
 144         str     r5, [r4, #PWR_CTRL_REG_OFFS]
 145
 146         @ set SDRAM self-refresh bit latch
 147         orr     r5, r5, #(1 << 8)
 148         str     r5, [r4, #PWR_CTRL_REG_OFFS]
 149
 150         @ clear SDRAM self-refresh bit latch
 151         and     r5, r5, #(~(1 << 8))
 152         str     r5, [r4, #PWR_CTRL_REG_OFFS]
 153
 154         @ clear SDRAM self-refresh bit
 155         and     r5, r5, #(~(1 << 9))
 156         str     r5, [r4, #PWR_CTRL_REG_OFFS]
 157
 158         @ wait for SDRAM to get into self-refresh mode
 159 2:      ldr     r3, [r2, #MPMC_STATUS_REG_OFFS]
 160         tst     r3, #(1 << 2)
 161         beq     2b
 162
 163         @ set 'get out of self-refresh mode after wakeup' bit
 164         orr     r5, r5, #(1 << 7)
 165         str     r5, [r4, #PWR_CTRL_REG_OFFS]
 166
 167         mcr     p15, 0, r0, c7, c0, 4   @ kinda sleeping now...
 168
 169         @ set SDRAM self-refresh bit latch
 170         orr     r5, r5, #(1 << 8)
 171         str     r5, [r4, #PWR_CTRL_REG_OFFS]
 172
 173         @ clear SDRAM self-refresh bit latch
 174         and     r5, r5, #(~(1 << 8))
 175         str     r5, [r4, #PWR_CTRL_REG_OFFS]
 176
 177         @ wait for SDRAM to get out self-refresh mode
 178 3:      ldr     r3, [r2, #MPMC_STATUS_REG_OFFS]
 179         tst     r3, #5
 180         bne     3b
 181
 182         @ restore regs and return
 183         ldmfd   sp!, {r0 - r6, pc}
 184
 185 ENTRY(pnx4008_cpu_standby_sz)
 186         .word   . - pnx4008_cpu_standby
 187
 188 ENTRY(pnx4008_cache_clean_invalidate)
 189         stmfd   sp!, {r0 - r6, lr}
 190 #ifdef CONFIG_CPU_DCACHE_WRITETHROUGH
 191         mcr     p15, 0, ip, c7, c6, 0           @ invalidate D cache
 192 #else
 193 1:      mrc     p15, 0, r15, c7, c14, 3         @ test,clean,invalidate
 194         bne     1b
 195 #endif
 196         ldmfd   sp!, {r0 - r6, pc}