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/linkage.h>
  15 #include <asm/assembler.h>
  16 #include <mach/hardware.h>
  17
  18 #define PWRMAN_VA_BASE IO_ADDRESS(PNX4008_PWRMAN_BASE)
  19 #define PWR_CTRL_REG_OFFS 0x44
  20
  21 #define SDRAM_CFG_VA_BASE IO_ADDRESS(PNX4008_SDRAM_CFG_BASE)
  22 #define MPMC_STATUS_REG_OFFS 0x4
  23
  24                 .text
  25
  26 ENTRY(pnx4008_cpu_suspend)
  27         @this function should be entered in Direct run mode.
  28
  29         @ save registers on stack
  30         stmfd   sp!, {r0 - r6, lr}
  31
  32         @ setup Power Manager base address in r4
  33         @ and put it's value in r5
  34         mov     r4, #(PWRMAN_VA_BASE & 0xff000000)
  35         orr     r4, r4, #(PWRMAN_VA_BASE & 0x00ff0000)
  36         orr     r4, r4, #(PWRMAN_VA_BASE & 0x0000ff00)
  37         orr     r4, r4, #(PWRMAN_VA_BASE & 0x000000ff)
  38         ldr     r5, [r4, #PWR_CTRL_REG_OFFS]
  39
  40         @ setup SDRAM controller base address in r2
  41         @ and put it's value in r3
  42         mov     r2, #(SDRAM_CFG_VA_BASE & 0xff000000)
  43         orr     r2, r2, #(SDRAM_CFG_VA_BASE & 0x00ff0000)
  44         orr     r2, r2, #(SDRAM_CFG_VA_BASE & 0x0000ff00)
  45         orr     r2, r2, #(SDRAM_CFG_VA_BASE & 0x000000ff)
  46         ldr     r3, [r2, #MPMC_STATUS_REG_OFFS] @extra read - HW bug workaround
  47
  48         @ clear SDRAM self-refresh bit latch
  49         and     r5, r5, #(~(1 << 8))
  50         @ clear SDRAM self-refresh bit
  51         and     r5, r5, #(~(1 << 9))
  52         str     r5, [r4, #PWR_CTRL_REG_OFFS]
  53
  54         @ do save current bit settings in r1
  55         mov     r1, r5
  56
  57         @ set SDRAM self-refresh bit
  58         orr     r5, r5, #(1 << 9)
  59         str     r5, [r4, #PWR_CTRL_REG_OFFS]
  60
  61         @ set SDRAM self-refresh bit latch
  62         orr     r5, r5, #(1 << 8)
  63         str     r5, [r4, #PWR_CTRL_REG_OFFS]
  64
  65         @ clear SDRAM self-refresh bit latch
  66         and     r5, r5, #(~(1 << 8))
  67         str     r5, [r4, #PWR_CTRL_REG_OFFS]
  68
  69         @ clear SDRAM self-refresh bit
  70         and     r5, r5, #(~(1 << 9))
  71         str     r5, [r4, #PWR_CTRL_REG_OFFS]
  72
  73         @ wait for SDRAM to get into self-refresh mode
  74 2:      ldr     r3, [r2, #MPMC_STATUS_REG_OFFS]
  75         tst     r3, #(1 << 2)
  76         beq     2b
  77
  78         @ to prepare SDRAM to get out of self-refresh mode after wakeup
  79         orr     r5, r5, #(1 << 7)
  80         str     r5, [r4, #PWR_CTRL_REG_OFFS]
  81
  82         @ do enter stop mode
  83         orr     r5, r5, #(1 << 0)
  84         str     r5, [r4, #PWR_CTRL_REG_OFFS]
  85         nop
  86         nop
  87         nop
  88         nop
  89         nop
  90         nop
  91         nop
  92         nop
  93         nop
  94
  95         @ sleeping now...
  96
  97         @ coming out of STOP mode into Direct Run mode
  98         @ clear STOP mode and SDRAM self-refresh bits
  99         str     r1, [r4, #PWR_CTRL_REG_OFFS]
 100
 101         @ wait for SDRAM to get out self-refresh mode
 102 3:      ldr     r3, [r2, #MPMC_STATUS_REG_OFFS]
 103         tst     r3, #5
 104         bne     3b
 105
 106         @ restore regs and return
 107         ldmfd   sp!, {r0 - r6, pc}
 108
 109 ENTRY(pnx4008_cpu_suspend_sz)
 110         .word   . - pnx4008_cpu_suspend
 111
 112 ENTRY(pnx4008_cpu_standby)
 113         @ save registers on stack
 114         stmfd   sp!, {r0 - r6, lr}
 115
 116         @ setup Power Manager base address in r4
 117         @ and put it's value in r5
 118         mov     r4, #(PWRMAN_VA_BASE & 0xff000000)
 119         orr     r4, r4, #(PWRMAN_VA_BASE & 0x00ff0000)
 120         orr     r4, r4, #(PWRMAN_VA_BASE & 0x0000ff00)
 121         orr     r4, r4, #(PWRMAN_VA_BASE & 0x000000ff)
 122         ldr     r5, [r4, #PWR_CTRL_REG_OFFS]
 123
 124         @ setup SDRAM controller base address in r2
 125         @ and put it's value in r3
 126         mov     r2, #(SDRAM_CFG_VA_BASE & 0xff000000)
 127         orr     r2, r2, #(SDRAM_CFG_VA_BASE & 0x00ff0000)
 128         orr     r2, r2, #(SDRAM_CFG_VA_BASE & 0x0000ff00)
 129         orr     r2, r2, #(SDRAM_CFG_VA_BASE & 0x000000ff)
 130         ldr     r3, [r2, #MPMC_STATUS_REG_OFFS] @extra read - HW bug workaround
 131
 132         @ clear SDRAM self-refresh bit latch
 133         and     r5, r5, #(~(1 << 8))
 134         @ clear SDRAM self-refresh bit
 135         and     r5, r5, #(~(1 << 9))
 136         str     r5, [r4, #PWR_CTRL_REG_OFFS]
 137
 138         @ do save current bit settings in r1
 139         mov     r1, r5
 140
 141         @ set SDRAM self-refresh bit
 142         orr     r5, r5, #(1 << 9)
 143         str     r5, [r4, #PWR_CTRL_REG_OFFS]
 144
 145         @ set SDRAM self-refresh bit latch
 146         orr     r5, r5, #(1 << 8)
 147         str     r5, [r4, #PWR_CTRL_REG_OFFS]
 148
 149         @ clear SDRAM self-refresh bit latch
 150         and     r5, r5, #(~(1 << 8))
 151         str     r5, [r4, #PWR_CTRL_REG_OFFS]
 152
 153         @ clear SDRAM self-refresh bit
 154         and     r5, r5, #(~(1 << 9))
 155         str     r5, [r4, #PWR_CTRL_REG_OFFS]
 156
 157         @ wait for SDRAM to get into self-refresh mode
 158 2:      ldr     r3, [r2, #MPMC_STATUS_REG_OFFS]
 159         tst     r3, #(1 << 2)
 160         beq     2b
 161
 162         @ set 'get out of self-refresh mode after wakeup' bit
 163         orr     r5, r5, #(1 << 7)
 164         str     r5, [r4, #PWR_CTRL_REG_OFFS]
 165
 166         mcr     p15, 0, r0, c7, c0, 4   @ kinda sleeping now...
 167
 168         @ set SDRAM self-refresh bit latch
 169         orr     r5, r5, #(1 << 8)
 170         str     r5, [r4, #PWR_CTRL_REG_OFFS]
 171
 172         @ clear SDRAM self-refresh bit latch
 173         and     r5, r5, #(~(1 << 8))
 174         str     r5, [r4, #PWR_CTRL_REG_OFFS]
 175
 176         @ wait for SDRAM to get out self-refresh mode
 177 3:      ldr     r3, [r2, #MPMC_STATUS_REG_OFFS]
 178         tst     r3, #5
 179         bne     3b
 180
 181         @ restore regs and return
 182         ldmfd   sp!, {r0 - r6, pc}
 183
 184 ENTRY(pnx4008_cpu_standby_sz)
 185         .word   . - pnx4008_cpu_standby
 186
 187 ENTRY(pnx4008_cache_clean_invalidate)
 188         stmfd   sp!, {r0 - r6, lr}
 189 #ifdef CONFIG_CPU_DCACHE_WRITETHROUGH
 190         mcr     p15, 0, ip, c7, c6, 0           @ invalidate D cache
 191 #else
 192 1:      mrc     p15, 0, r15, c7, c14, 3         @ test,clean,invalidate
 193         bne     1b
 194 #endif
 195         ldmfd   sp!, {r0 - r6, pc}