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Diffstat (limited to 'arch/arm/mach-sa1100/sleep.S')
| -rw-r--r-- | arch/arm/mach-sa1100/sleep.S | 215 |
1 files changed, 215 insertions, 0 deletions
diff --git a/arch/arm/mach-sa1100/sleep.S b/arch/arm/mach-sa1100/sleep.S new file mode 100644 index 000000000000..2fa1e289d177 --- /dev/null +++ b/arch/arm/mach-sa1100/sleep.S @@ -0,0 +1,215 @@ +/* + * 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 + + |