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+/*
+ * SA11x0 Assembler Sleep/WakeUp Management Routines
+ *
+ * Copyright (c) 2001 Cliff Brake <cbrake@accelent.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License.
+ *
+ * History:
+ *
+ * 2001-02-06: Cliff Brake Initial code
+ *
+ * 2001-08-29: Nicolas Pitre Simplified.
+ *
+ * 2002-05-27: Nicolas Pitre Revisited, more cleanup and simplification.
+ * Storage is on the stack now.
+ */
+
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+#include <mach/hardware.h>
+
+ .text
+/*
+ * sa1100_finish_suspend()
+ *
+ * Causes sa11x0 to enter sleep state
+ *
+ * Must be aligned to a cacheline.
+ */
+ .balign 32
+ENTRY(sa1100_finish_suspend)
+ @ disable clock switching
+ mcr p15, 0, r1, c15, c2, 2
+
+ ldr r6, =MDREFR
+ ldr r4, [r6]
+ orr r4, r4, #MDREFR_K1DB2
+ ldr r5, =PPCR
+
+ @ Pre-load __loop_udelay into the I-cache
+ mov r0, #1
+ bl __loop_udelay
+ mov r0, r0
+
+ @ The following must all exist in a single cache line to
+ @ avoid accessing memory until this sequence is complete,
+ @ otherwise we occasionally hang.
+
+ @ Adjust memory timing before lowering CPU clock
+ str r4, [r6]
+
+ @ delay 90us and set CPU PLL to lowest speed
+ @ fixes resume problem on high speed SA1110
+ mov r0, #90
+ bl __loop_udelay
+ mov r1, #0
+ str r1, [r5]
+ mov r0, #90
+ bl __loop_udelay
+
+ /*
+ * SA1110 SDRAM controller workaround. register values:
+ *
+ * r0 = &MSC0
+ * r1 = &MSC1
+ * r2 = &MSC2
+ * r3 = MSC0 value
+ * r4 = MSC1 value
+ * r5 = MSC2 value
+ * r6 = &MDREFR
+ * r7 = first MDREFR value
+ * r8 = second MDREFR value
+ * r9 = &MDCNFG
+ * r10 = MDCNFG value
+ * r11 = third MDREFR value
+ * r12 = &PMCR
+ * r13 = PMCR value (1)
+ */
+
+ ldr r0, =MSC0
+ ldr r1, =MSC1
+ ldr r2, =MSC2
+
+ ldr r3, [r0]
+ bic r3, r3, #FMsk(MSC_RT)
+ bic r3, r3, #FMsk(MSC_RT)<<16
+
+ ldr r4, [r1]
+ bic r4, r4, #FMsk(MSC_RT)
+ bic r4, r4, #FMsk(MSC_RT)<<16
+
+ ldr r5, [r2]
+ bic r5, r5, #FMsk(MSC_RT)
+ bic r5, r5, #FMsk(MSC_RT)<<16
+
+ ldr r7, [r6]
+ bic r7, r7, #0x0000FF00
+ bic r7, r7, #0x000000F0
+ orr r8, r7, #MDREFR_SLFRSH
+
+ ldr r9, =MDCNFG
+ ldr r10, [r9]
+ bic r10, r10, #(MDCNFG_DE0+MDCNFG_DE1)
+ bic r10, r10, #(MDCNFG_DE2+MDCNFG_DE3)
+
+ bic r11, r8, #MDREFR_SLFRSH
+ bic r11, r11, #MDREFR_E1PIN
+
+ ldr r12, =PMCR
+
+ mov r13, #PMCR_SF
+
+ b sa1110_sdram_controller_fix
+
+ .align 5
+sa1110_sdram_controller_fix:
+
+ @ Step 1 clear RT field of all MSCx registers
+ str r3, [r0]
+ str r4, [r1]
+ str r5, [r2]
+
+ @ Step 2 clear DRI field in MDREFR
+ str r7, [r6]
+
+ @ Step 3 set SLFRSH bit in MDREFR
+ str r8, [r6]
+
+ @ Step 4 clear DE bis in MDCNFG
+ str r10, [r9]
+
+ @ Step 5 clear DRAM refresh control register
+ str r11, [r6]
+
+ @ Wow, now the hardware suspend request pins can be used, that makes them functional for
+ @ about 7 ns out of the entire time that the CPU is running!
+
+ @ Step 6 set force sleep bit in PMCR
+
+ str r13, [r12]
+
+20: b 20b @ loop waiting for sleep