1 files changed, 194 insertions, 0 deletions

diff --git a/arch/arm/mach-pxa/sleep.S b/arch/arm/mach-pxa/sleep.S
new file mode 100644
index 000000000000..16cad2c2497c
--- /dev/null
+++ b/arch/arm/mach-pxa/sleep.S
@@ -0,0 +1,194 @@
+/*
+ * Low-level PXA250/210 sleep/wakeUp support
+ *
+ * Initial SA1110 code:
+ * Copyright (c) 2001 Cliff Brake <cbrake@accelent.com>
+ *
+ * Adapted for PXA by Nicolas Pitre:
+ * Copyright (c) 2002 Monta Vista Software, Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License.
+ */
+
+#include <linux/config.h>
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+#include <asm/hardware.h>
+
+#include <asm/arch/pxa-regs.h>
+
+                .text
+
+/*
+ * pxa_cpu_suspend()
+ *
+ * Forces CPU into sleep state
+ */
+
+ENTRY(pxa_cpu_suspend)
+
+        mra     r2, r3, acc0
+        stmfd   sp!, {r2 - r12, lr}             @ save registers on stack
+
+        @ get coprocessor registers
+        mrc     p14, 0, r3, c6, c0, 0           @ clock configuration, for turbo mode
+        mrc     p15, 0, r4, c15, c1, 0          @ CP access reg
+        mrc     p15, 0, r5, c13, c0, 0          @ PID
+        mrc     p15, 0, r6, c3, c0, 0           @ domain ID
+        mrc     p15, 0, r7, c2, c0, 0           @ translation table base addr
+        mrc     p15, 0, r8, c1, c1, 0           @ auxiliary control reg
+        mrc     p15, 0, r9, c1, c0, 0           @ control reg
+
+        bic     r3, r3, #2                      @ clear frequency change bit
+
+        @ store them plus current virtual stack ptr on stack
+        mov     r10, sp
+        stmfd   sp!, {r3 - r10}
+
+        @ preserve phys address of stack
+        mov     r0, sp
+        bl      sleep_phys_sp
+        ldr     r1, =sleep_save_sp
+        str     r0, [r1]
+
+        @ clean data cache
+        bl      xscale_flush_kern_cache_all
+
+        @ Put the processor to sleep
+        @ (also workaround for sighting 28071)
+
+        @ prepare value for sleep mode
+        mov     r1, #3                          @ sleep mode
+
+        @ prepare to put SDRAM into self-refresh manually
+        ldr     r4, =MDREFR
+        ldr     r5, [r4]
+        orr     r5, r5, #MDREFR_SLFRSH
+
+        @ prepare pointer to physical address 0 (virtual mapping in generic.c)
+        mov     r2, #UNCACHED_PHYS_0
+
+        @ Intel PXA255 Specification Update notes problems
+        @ about suspending with PXBus operating above 133MHz
+        @ (see Errata 31, GPIO output signals, ... unpredictable in sleep
+        @
+        @ We keep the change-down close to the actual suspend on SDRAM
+        @ as possible to eliminate messing about with the refresh clock
+        @ as the system will restore with the original speed settings
+        @
+        @ Ben Dooks, 13-Sep-2004
+
+        ldr     r6, =CCCR
+        ldr     r8, [r6]                @ keep original value for resume
+
+        @ ensure x1 for run and turbo mode with memory clock
+        bic     r7, r8, #CCCR_M_MASK | CCCR_N_MASK
+        orr     r7, r7, #(1<<5) | (2<<7)
+
+        @ check that the memory frequency is within limits
+        and     r14, r7, #CCCR_L_MASK
+        teq     r14, #1
+        bicne   r7, r7, #CCCR_L_MASK
+        orrne   r7, r7, #1                      @@ 99.53MHz
+
+        @ get ready for the change
+
+        @ note, turbo is not preserved over sleep so there is no
+        @ point in preserving it here. we save it on the stack with the
+        @ other CP registers instead.
+        mov     r0, #0
+        mcr     p14, 0, r0, c6, c0, 0
+        orr     r0, r0, #2                      @ initiate change bit
+
+        @ align execution to a cache line
+        b       1f
+
+        .ltorg
+        .align  5
+1:
+
+        @ All needed values are now in registers.
+        @ These last instructions should be in cache
+
+        @ initiate the frequency change...
+        str     r7, [r6]
+        mcr     p14, 0, r0, c6, c0, 0
+
+        @ restore the original cpu speed value for resume
+        str     r8, [r6]
+
+        @ put SDRAM into self-refresh
+        str     r5, [r4]
+
+        @ force address lines low by reading at physical address 0
+        ldr     r3, [r2]
+
+        @ enter sleep mode
+        mcr     p14, 0, r1, c7, c0, 0
+
+20:     b       20b                             @ loop waiting for sleep
+
+/*
+ * cpu_pxa_resume()
+ *
+ * entry point from bootloader into kernel during resume
+ *
+ * Note: Yes, part of the following code is located into the .data section.
+ *       This is to allow sleep_save_sp to be accessed with a relative load
+ *       while we can't rely on any MMU translation.  We could have put
+ *       sleep_save_sp in the .text section as well, but some setups might
+ *       insist on it to be truly read-only.
+ */
+
+        .data
+        .align 5
+ENTRY(pxa_cpu_resume)
+        mov     r0, #PSR_I_BIT | PSR_F_BIT | MODE_SVC   @ set SVC, irqs off
+        msr     cpsr_c, r0
+
+        ldr     r0, sleep_save_sp               @ stack phys addr
+        ldr     r2, =resume_after_mmu           @ its absolute virtual address
+        ldmfd   r0, {r3 - r9, sp}               @ CP regs + virt stack ptr
+
+        mov     r1, #0
+        mcr     p15, 0, r1, c8, c7, 0           @ invalidate I & D TLBs
+        mcr     p15, 0, r1, c7, c7, 0           @ invalidate I & D caches, BTB
+
+#ifdef CONFIG_XSCALE_CACHE_ERRATA
+        bic     r9, r9, #0x0004                 @ see cpu_xscale_proc_init
+#endif
+
+        mcr     p14, 0, r3, c6, c0, 0           @ clock configuration, turbo mode.
+        mcr     p15, 0, r4, c15, c1, 0          @ CP access reg
+        mcr     p15, 0, r5, c13, c0, 0          @ PID
+        mcr     p15, 0, r6, c3, c0, 0           @ domain ID
+        mcr     p15, 0, r7, c2, c0, 0           @ translation table base addr
+        mcr     p15, 0, r8, c1, c1, 0           @ auxiliary control reg
+        b       resume_turn_on_mmu              @ cache align execution
+
+        .align 5
+resume_turn_on_mmu:
+        mcr     p15, 0, r9, c1, c0, 0           @ turn on MMU, caches, etc.
+
+        @ Let us ensure we jump to resume_after_mmu only when the mcr above
+        @ actually took effect.  They call it the "cpwait" operation.
+        mrc     p15, 0, r1, c2, c0, 0           @ queue a dependency on CP15
+        sub     pc, r2, r1, lsr #32             @ jump to virtual addr
+        nop
+        nop
+        nop
+
+sleep_save_sp:
+        .word   0                               @ preserve stack phys ptr here
+
+        .text
+resume_after_mmu:
+#ifdef CONFIG_XSCALE_CACHE_ERRATA
+        bl      cpu_xscale_proc_init
+#endif
+        ldmfd   sp!, {r2, r3}
+        mar     acc0, r2, r3
+        ldmfd   sp!, {r4 - r12, pc}             @ return to caller
+
+