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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 <asm/hardware.h>
+
+
+
+ .text
+
+
+
+/*
+ * sa1100_cpu_suspend()
+ *
+ * Causes sa11x0 to enter sleep state
+ *
+ */
+
+ENTRY(sa1100_cpu_suspend)
+
+ stmfd sp!, {r4 - r12, lr} @ save registers on stack
+
+ @ get coprocessor registers
+ mrc p15, 0, r4, c3, c0, 0 @ domain ID
+ mrc p15, 0, r5, c2, c0, 0 @ translation table base addr
+ mrc p15, 0, r6, c13, c0, 0 @ PID
+ mrc p15, 0, r7, c1, c0, 0 @ control reg
+
+ @ store them plus current virtual stack ptr on stack
+ mov r8, sp
+ stmfd sp!, {r4 - r8}
+
+ @ preserve phys address of stack
+ mov r0, sp
+ bl sleep_phys_sp
+ ldr r1, =sleep_save_sp
+ str r0, [r1]
+
+ @ clean data cache and invalidate WB
+ bl v4wb_flush_kern_cache_all
+
+ @ disable clock switching
+ mcr p15, 0, r1, c15, c2, 2
+
+ @ Adjust memory timing before lowering CPU clock
+ @ Clock speed adjustment without changing memory timing makes
+ @ CPU hang in some cases
+ ldr r0, =MDREFR
+ ldr r1, [r0]
+ orr r1, r1, #MDREFR_K1DB2
+ str r1, [r0]
+
+ @ delay 90us and set CPU PLL to lowest speed
+ @ fixes resume problem on high speed SA1110
+ mov r0, #90
+ bl __udelay
+ ldr r0, =PPCR
+ mov r1, #0
+ str r1, [r0]
+ mov r0, #90
+ bl __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 r6, =MDREFR
+
+ 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
+
+/*
+ * cpu_sa1100_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(sa1100_cpu_resume)
+ mov r0, #PSR_F_BIT | PSR_I_BIT | MODE_SVC
+ msr cpsr_c, r0 @ set SVC, irqs off
+
+ ldr r0, sleep_save_sp @ stack phys addr
+ ldr r2, =resume_after_mmu @ its absolute virtual address
+ ldmfd r0, {r4 - r7, sp} @ CP regs + virt stack ptr
+
+ mov r1, #0
+ mcr p15, 0, r1, c8, c7, 0 @ flush I+D TLBs
+ mcr p15, 0, r1, c7, c7, 0 @ flush I&D cache
+ mcr p15, 0, r1, c9, c0, 0 @ invalidate RB
+ mcr p15, 0, r1, c9, c0, 5 @ allow user space to use RB
+
+ mcr p15, 0, r4, c3, c0, 0 @ domain ID
+ mcr p15, 0, r5, c2, c0, 0 @ translation table base addr
+ mcr p15, 0, r6, c13, c0, 0 @ PID
+ b resume_turn_on_mmu @ cache align execution
+
+ .align 5
+resume_turn_on_mmu:
+ mcr p15, 0, r7, c1, c0, 0 @ turn on MMU, caches, etc.
+ nop
+ mov pc, r2 @ jump to virtual addr
+ nop
+ nop
+ nop
+
+sleep_save_sp:
+ .word 0 @ preserve stack phys ptr here
+
+ .text
+resume_after_mmu:
+ mcr p15, 0, r1, c15, c1, 2 @ enable clock switching
+ ldmfd sp!, {r4 - r12, pc} @ return to caller
+
+