On Wed, Oct 31, 2007 at 04:12:36AM +0900, Hyon Lim wrote: > Hello. I need a help for my implementation work on MIPS software suspend. > From 3month ago, I've been coding software suspend(swsusp) on MIPS arch. > I'm developing with MIPS32 4KEc embedded processor for digital appliance. > > Swsusp has two procedure. the one is suspending procedure and other one is > resume procedure. > Yesterday, I confirmed suspending procedure working. > This is a porting guide of swsusp ( > http://tree.celinuxforum.org/CelfPubWiki/SwSuspendPortingNotes) > I refered this article. The article is a bit dated and lacking alot of details. > The problem I faced is assembly language for MIPS. > Of course, there are many manuals for this work but, I need a help from MIPS > expert. > > This pseudo code should be implemented by MIPS asm. > > for (j = nr_copy_pages; j>0; j--) { > src = pagedir_nosave[j].src; > dst = pagedir_nosave[j].dst; > for (i=0;i<1024;i++) { > *dst++ = *src++; > } > } > > nr_copy_pages is unsigned long variable. The page is refering to some old code which no longer seems to exist in this form. The array pagedir_nosave has now become a chained list. I attach a patch for illustration purposes. It illustrates how things work on recent kernels; I didn't have a 2.6.10 kernel at hand. If you have further questions on MIPS assembler then I suggest you get a copy of Dominik Sweetman's excellent "See MIPS Run Linux" book. > and pagedir_nosave is a > suspend_pagedir_t<http://lxr.linux.no/source/kernel/power/ident?v=2.6.10;i=suspend_pagedir_t>type > structure array(pointer). (you can refer following url. Line 101. : > http://lxr.linux.no/source/kernel/power/swsusp.c?v=2.6.10) > code skeleton or useful material will be welcomed. (whatever you have.) > > The second problem is > " which register should be prevented? " > > I saved $v0-v1. $a0-$a3. $t0-t7. $s0-s7. $t8-t9. $gp,sp,fp,ra. That sounds about right but I'd need to dive deeper into swsusp to give you a definitive answer. Cheers, Ralf [MIPS] Skeleton swsusp implementation. Signed-off-by: Ralf Baechle <ralf@xxxxxxxxxxxxxx> diff --git a/arch/mips/kernel/Makefile b/arch/mips/kernel/Makefile index 3196509..38adf9e 100644 --- a/arch/mips/kernel/Makefile +++ b/arch/mips/kernel/Makefile @@ -75,6 +75,8 @@ obj-$(CONFIG_PCSPEAKER) += pcspeaker.o obj-$(CONFIG_KEXEC) += machine_kexec.o relocate_kernel.o obj-$(CONFIG_EARLY_PRINTK) += early_printk.o +obj-$(CONFIG_HIBERNATION) += swsusp.o suspend.o + CFLAGS_cpu-bugs64.o = $(shell if $(CC) $(KBUILD_CFLAGS) -Wa,-mdaddi -c -o /dev/null -xc /dev/null >/dev/null 2>&1; then echo "-DHAVE_AS_SET_DADDI"; fi) obj-$(CONFIG_HAVE_STD_PC_SERIAL_PORT) += 8250-platform.o diff --git a/arch/mips/kernel/asm-offsets.c b/arch/mips/kernel/asm-offsets.c index ca13629..f3038dc 100644 --- a/arch/mips/kernel/asm-offsets.c +++ b/arch/mips/kernel/asm-offsets.c @@ -13,6 +13,7 @@ #include <linux/sched.h> #include <linux/mm.h> #include <linux/interrupt.h> +#include <linux/suspend.h> #include <asm/ptrace.h> #include <asm/processor.h> @@ -337,3 +338,13 @@ void output_irq_cpustat_t_defines(void) size("#define IC_IRQ_CPUSTAT_T ", irq_cpustat_t); linefeed; } + +void output_pbe_defines(void) +{ + text("/* Linux struct pbe offsets. */"); + offset("#define PBE_ADDRESS ", struct pbe, address); + offset("#define PBE_ORIG_ADDRESS ", struct pbe, orig_address); + offset("#define PBE_NEXT ", struct pbe, next); + size("#define PBE_SIZE ", struct pbe); + linefeed; +} diff --git a/arch/mips/kernel/suspend.S b/arch/mips/kernel/suspend.S new file mode 100644 index 0000000..32b3ec0 --- /dev/null +++ b/arch/mips/kernel/suspend.S @@ -0,0 +1,20 @@ +#include <asm/asm-offsets.h> +#include <asm/regdef.h> +#include <asm/asm.h> + +LEAF(swsusp_arch_suspend) + END(swsusp_arch_suspend) + +LEAF(swsusp_arch_resume) + PTR_LA t0, restore_pblist +0: PTR_L t1, PBE_ADDRESS(t1) + PTR_L t2, PBE_ORIG_ADDRESS(t1) + PTR_ADDIU t3, t1, _PAGE_SIZE +1: REG_L t4, (t1) + REG_S t4, (t1) + PTR_ADDIU t1, t1, SZREG + PTR_ADDIU t2, t2, SZREG + bne t1, t3, 1b + PTR_L t1, PBE_NEXT(t1) + bnez t1, 0 + END(swsusp_arch_resume) diff --git a/arch/mips/kernel/swsusp.c b/arch/mips/kernel/swsusp.c new file mode 100644 index 0000000..864dd49 --- /dev/null +++ b/arch/mips/kernel/swsusp.c @@ -0,0 +1,30 @@ +/* + * Suspend support specific for power. + * + * Distribute under GPLv2 + * + * Copyright (c) 2002 Pavel Machek <pavel@xxxxxxx> + * Copyright (c) 2001 Patrick Mochel <mochel@xxxxxxxx> + */ + +#include <asm/page.h> + +/* References to section boundaries */ +extern const void __nosave_begin, __nosave_end; + +void save_processor_state(void) +{ + /* ... */ +} + +void restore_processor_state(void) +{ + /* ... */ +} + +int pfn_is_nosave(unsigned long pfn) +{ + unsigned long nosave_begin_pfn = __pa(&__nosave_begin) >> PAGE_SHIFT; + unsigned long nosave_end_pfn = PAGE_ALIGN(__pa(&__nosave_end)) >> PAGE_SHIFT; + return (pfn >= nosave_begin_pfn) && (pfn < nosave_end_pfn); +} diff --git a/include/asm-mips/suspend.h b/include/asm-mips/suspend.h index 2562f8f..ee5e679 100644 --- a/include/asm-mips/suspend.h +++ b/include/asm-mips/suspend.h @@ -1,6 +1,9 @@ #ifndef __ASM_SUSPEND_H #define __ASM_SUSPEND_H -/* Somewhen... Maybe :-) */ +static inline int arch_prepare_suspend(void) +{ + return 0; +} #endif /* __ASM_SUSPEND_H */ diff --git a/include/linux/suspend.h b/include/linux/suspend.h index 4360e08..854b7a9 100644 --- a/include/linux/suspend.h +++ b/include/linux/suspend.h @@ -1,7 +1,7 @@ #ifndef _LINUX_SUSPEND_H #define _LINUX_SUSPEND_H -#if defined(CONFIG_X86) || defined(CONFIG_FRV) || defined(CONFIG_PPC32) || defined(CONFIG_PPC64) +#if defined(CONFIG_X86) || defined(CONFIG_FRV) || defined(CONFIG_PPC32) || defined(CONFIG_PPC64) || defined(CONFIG_MIPS) #include <asm/suspend.h> #endif #include <linux/swap.h> diff --git a/kernel/power/Kconfig b/kernel/power/Kconfig index 8e186c6..444f835 100644 --- a/kernel/power/Kconfig +++ b/kernel/power/Kconfig @@ -99,13 +99,13 @@ config SUSPEND config HIBERNATION_UP_POSSIBLE bool - depends on X86 || PPC64_SWSUSP || PPC32 + depends on MIPS || X86 || PPC64_SWSUSP || PPC32 depends on !SMP default y config HIBERNATION_SMP_POSSIBLE bool - depends on (X86 && !X86_VOYAGER) || PPC64_SWSUSP + depends on MIPS || (X86 && !X86_VOYAGER) || PPC64_SWSUSP depends on SMP default y
