2 * SA11x0 Assembler Sleep/WakeUp Management Routines
4 * Copyright (c) 2001 Cliff Brake <cbrake@accelent.com>
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License.
11 * 2001-02-06: Cliff Brake Initial code
13 * 2001-08-29: Nicolas Pitre Simplified.
15 * 2002-05-27: Nicolas Pitre Revisited, more cleanup and simplification.
16 * Storage is on the stack now.
19 #include <linux/linkage.h>
20 #include <asm/assembler.h>
21 #include <asm/hardware.h>
27 * sa1100_cpu_suspend()
29 * Causes sa11x0 to enter sleep state
33 ENTRY(sa1100_cpu_suspend)
35 stmfd sp!, {r4 - r12, lr} @ save registers on stack
37 @ get coprocessor registers
38 mrc p15, 0, r4, c3, c0, 0 @ domain ID
39 mrc p15, 0, r5, c2, c0, 0 @ translation table base addr
40 mrc p15, 0, r6, c13, c0, 0 @ PID
41 mrc p15, 0, r7, c1, c0, 0 @ control reg
43 @ store them plus current virtual stack ptr on stack
47 @ preserve phys address of stack
50 ldr r1, =sleep_save_sp
53 @ clean data cache and invalidate WB
54 bl cpu_sa1100_cache_clean_invalidate_all
56 @ disable clock switching
57 mcr p15, 0, r1, c15, c2, 2
59 @ Adjust memory timing before lowering CPU clock
60 @ Clock speed adjustment without changing memory timing makes
61 @ CPU hang in some cases
64 orr r1, r1, #MDREFR_K1DB2
67 @ delay 90us and set CPU PLL to lowest speed
68 @ fixes resume problem on high speed SA1110
70 bl SYMBOL_NAME(__udelay)
75 bl SYMBOL_NAME(__udelay)
78 * SA1110 SDRAM controller workaround. register values:
87 * r7 = first MDREFR value
88 * r8 = second MDREFR value
91 * r11 = third MDREFR value
93 * r13 = PMCR value (1)
101 bic r3, r3, #FMsk(MSC_RT)
102 bic r3, r3, #FMsk(MSC_RT)<<16
105 bic r4, r4, #FMsk(MSC_RT)
106 bic r4, r4, #FMsk(MSC_RT)<<16
109 bic r5, r5, #FMsk(MSC_RT)
110 bic r5, r5, #FMsk(MSC_RT)<<16
115 bic r7, r7, #0x0000FF00
116 bic r7, r7, #0x000000F0
117 orr r8, r7, #MDREFR_SLFRSH
121 bic r10, r10, #(MDCNFG_DE0+MDCNFG_DE1)
122 bic r10, r10, #(MDCNFG_DE2+MDCNFG_DE3)
124 bic r11, r8, #MDREFR_SLFRSH
125 bic r11, r11, #MDREFR_E1PIN
131 b sa1110_sdram_controller_fix
134 sa1110_sdram_controller_fix:
136 @ Step 1 clear RT field of all MSCx registers
141 @ Step 2 clear DRI field in MDREFR
144 @ Step 3 set SLFRSH bit in MDREFR
147 @ Step 4 clear DE bis in MDCNFG
150 @ Step 5 clear DRAM refresh control register
153 @ Wow, now the hardware suspend request pins can be used, that makes them functional for
154 @ about 7 ns out of the entire time that the CPU is running!
156 @ Step 6 set force sleep bit in PMCR
160 20: b 20b @ loop waiting for sleep
163 * cpu_sa1100_resume()
165 * entry point from bootloader into kernel during resume
167 * Note: Yes, part of the following code is located into the .data section.
168 * This is to allow sleep_save_sp to be accessed with a relative load
169 * while we can't rely on any MMU translation. We could have put
170 * sleep_save_sp in the .text section as well, but some setups might
171 * insist on .text to be truely read-only.
176 ENTRY(sa1100_cpu_resume)
177 mov r0, #I_BIT | F_BIT | MODE_SVC @ set SVC, irqs off
180 ldr r0, sleep_save_sp @ stack phys addr
181 ldr r2, =resume_after_mmu @ its absolute virtual address
182 ldmfd r0, {r4 - r7, sp} @ CP regs + virt stack ptr
185 mcr p15, 0, r1, c8, c7, 0 @ flush I+D TLBs
186 mcr p15, 0, r1, c7, c7, 0 @ flush I&D cache
187 mcr p15, 0, r1, c9, c0, 0 @ invalidate RB
188 mcr p15, 0, r1, c9, c0, 5 @ allow user space to use RB
190 mcr p15, 0, r4, c3, c0, 0 @ domain ID
191 mcr p15, 0, r5, c2, c0, 0 @ translation table base addr
192 mcr p15, 0, r6, c13, c0, 0 @ PID
193 b resume_turn_on_mmu @ cache align execution
197 mcr p15, 0, r7, c1, c0, 0 @ turn on MMU, caches, etc.
199 mov pc, r2 @ jump to virtual addr
205 .word 0 @ preserve stack phys ptr here
209 mcr p15, 0, r1, c15, c1, 2 @ enable clock switching
210 ldmfd sp!, {r4 - r12, pc} @ return to caller