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+/*
+ * 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/linkage.h>
+#include <asm/assembler.h>
+#include <mach/hardware.h>
+#include <mach/smemc.h>
+#include <mach/pxa2xx-regs.h>
+
+#define MDREFR_KDIV 0x200a4000 // all banks
+#define CCCR_SLEEP 0x00000107 // L=7 2N=2 A=0 PPDIS=0 CPDIS=0
+
+ .text
+
+#ifdef CONFIG_PXA3xx
+/*
+ * pxa3xx_finish_suspend() - forces CPU into sleep state (S2D3C4)
+ */
+ENTRY(pxa3xx_finish_suspend)
+ mov r0, #0x06 @ S2D3C4 mode
+ mcr p14, 0, r0, c7, c0, 0 @ enter sleep
+
+20: b 20b @ waiting for sleep
+#endif /* CONFIG_PXA3xx */
+
+#ifdef CONFIG_PXA27x
+/*
+ * pxa27x_finish_suspend()
+ *
+ * Forces CPU into sleep state.
+ *
+ * r0 = value for PWRMODE M field for desired sleep state
+ */
+ENTRY(pxa27x_finish_suspend)
+ @ Put the processor to sleep
+ @ (also workaround for sighting 28071)
+
+ @ prepare value for sleep mode
+ mov r1, r0 @ sleep mode
+
+ @ prepare pointer to physical address 0 (virtual mapping in generic.c)
+ mov r2, #UNCACHED_PHYS_0
+
+ @ prepare SDRAM refresh settings
+ ldr r4, =MDREFR
+ ldr r5, [r4]
+
+ @ enable SDRAM self-refresh mode
+ orr r5, r5, #MDREFR_SLFRSH
+
+ @ set SDCLKx divide-by-2 bits (this is part of a workaround for Errata 50)
+ ldr r6, =MDREFR_KDIV
+ orr r5, r5, r6
+
+ @ Intel PXA270 Specification Update notes problems sleeping
+ @ with core operating above 91 MHz
+ @ (see Errata 50, ...processor does not exit from sleep...)
+
+ ldr r6, =CCCR
+ ldr r8, [r6] @ keep original value for resume
+
+ ldr r7, =CCCR_SLEEP @ prepare CCCR sleep value
+ mov r0, #0x2 @ prepare value for CLKCFG
+
+ @ align execution to a cache line
+ b pxa_cpu_do_suspend
+#endif
+
+#ifdef CONFIG_PXA25x
+/*
+ * pxa25x_finish_suspend()
+ *
+ * Forces CPU into sleep state.
+ *
+ * r0 = value for PWRMODE M field for desired sleep state
+ */
+
+ENTRY(pxa25x_finish_suspend)
+ @ prepare value for sleep mode
+ mov r1, r0 @ sleep mode
+
+ @ prepare pointer to physical address 0 (virtual mapping in generic.c)
+ mov r2, #UNCACHED_PHYS_0
+
+ @ prepare SDRAM refresh settings
+ ldr r4, =MDREFR
+ ldr r5, [r4]
+
+ @ enable SDRAM self-refresh mode
+ orr r5, r5, #MDREFR_SLFRSH
+
+ @ 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
+ b pxa_cpu_do_suspend
+#endif
+
+ .ltorg
+ .align 5
+pxa_cpu_do_suspend:
+
+ @ 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]
+
+ @ need 6 13-MHz cycles before changing PWRMODE
+ @ just set frequency to 91-MHz... 6*91/13 = 42
+
+ mov r0, #42
+10: subs r0, r0, #1
+ bne 10b
+
+ @ Do not reorder...
+ @ Intel PXA270 Specification Update notes problems performing
+ @ external accesses after SDRAM is put in self-refresh mode
+ @ (see Errata 38 ...hangs when entering self-refresh mode)
+
+ @ force address lines low by reading at physical address 0
+ ldr r3, [r2]
+
+ @ put SDRAM into self-refresh
+ str r5, [r4]
+
+ @ enter sleep mode
+ mcr p14, 0, r1, c7, c0, 0 @ PWRMODE
+
+20: b 20b @ loop waiting for sleep