[Gnewsense-dev] Re: [loongson-PATCH-v1 22/27] Hibernation Support in mips system

[Atsushi Nemoto]

On Thu, 21 May 2009 06:11:11 +0800, address@hidden wrote:
> --- /dev/null
> +++ b/arch/mips/power/cpu.c
> @@ -0,0 +1,51 @@
> +/*
> + * Suspend support specific for mips.
> + *
> + */
> +#include <linux/mm.h>
> +#include <asm/mipsregs.h>
> +#include <asm/page.h>
> +#include <linux/suspend.h>
> +
> +/* References to section boundaries */
> +extern const void __nosave_begin, __nosave_end;
> +
> +static uint32_t saved_status;
> +unsigned long
> +     saved_ra,
> +     saved_sp,
> +     saved_fp,
> +     saved_gp,
> +     saved_s0,
> +     saved_s1,
> +     saved_s2,
> +     saved_s3,
> +     saved_s4,
> +     saved_s5,
> +     saved_s6,
> +     saved_s7,
> +     saved_a0,
> +     saved_a1,
> +     saved_a2,
> +     saved_a3,
> +     saved_v0,
> +     saved_v1;

Instead of enumerating them, I would prefer something like "struct
pt_regs saved_regs" or "unsigned long saved_regs[32]".

> +void save_processor_state(void)
> +{
> +     saved_status = read_c0_status();
> +}

No need to save/restore floating point registers?

> +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;

Unneeded backslash concatenation.
PFN_UP(), PFN_DOWN() can be used.

> +LEAF(swsusp_arch_suspend)
> +     PTR_LA t0, saved_ra
> +     PTR_S ra, (t0)
> +     PTR_LA t0, saved_sp
> +     PTR_S sp, (t0)

The MIPS assembly language accepts symbol for PTR_S, i.e.:

        PTR_S ra, saved_ra

Or, if you converted saved_xxx into struct or array, you can do
something like this:

        PTR_LA t0, saved_regs
        PTR_S ra, PT_R31(t0)
        PTR_S sp, PT_R29(t0)
        ...

> +     j swsusp_save
> +     nop

This nop is required?

---
Atsushi Nemoto