[PATCH v2 10/22] ARM: LPAE: use phys_addr_t in switch_mm()

[Nicolas Pitre]

On Fri, 10 Aug 2012, Cyril Chemparathy wrote:

> This patch modifies the switch_mm() processor functions to use phys_addr_t.
> On LPAE systems, we now honor the upper 32-bits of the physical address that
> is being passed in, and program these into TTBR as expected.
> 
> Signed-off-by: Cyril Chemparathy <cyril at ti.com>
> Signed-off-by: Vitaly Andrianov <vitalya at ti.com>
> ---
>  arch/arm/include/asm/proc-fns.h |    4 ++--
>  arch/arm/mm/proc-v7-3level.S    |   26 ++++++++++++++++++++++----
>  2 files changed, 24 insertions(+), 6 deletions(-)
> 
> diff --git a/arch/arm/include/asm/proc-fns.h b/arch/arm/include/asm/proc-fns.h
> index f3628fb..75b5f14 100644
> --- a/arch/arm/include/asm/proc-fns.h
> +++ b/arch/arm/include/asm/proc-fns.h
> @@ -60,7 +60,7 @@ extern struct processor {
>  	/*
>  	 * Set the page table
>  	 */
> -	void (*switch_mm)(unsigned long pgd_phys, struct mm_struct *mm);
> +	void (*switch_mm)(phys_addr_t pgd_phys, struct mm_struct *mm);
>  	/*
>  	 * Set a possibly extended PTE.  Non-extended PTEs should
>  	 * ignore 'ext'.
> @@ -82,7 +82,7 @@ extern void cpu_proc_init(void);
>  extern void cpu_proc_fin(void);
>  extern int cpu_do_idle(void);
>  extern void cpu_dcache_clean_area(void *, int);
> -extern void cpu_do_switch_mm(unsigned long pgd_phys, struct mm_struct *mm);
> +extern void cpu_do_switch_mm(phys_addr_t pgd_phys, struct mm_struct *mm);
>  #ifdef CONFIG_ARM_LPAE
>  extern void cpu_set_pte_ext(pte_t *ptep, pte_t pte);
>  #else
> diff --git a/arch/arm/mm/proc-v7-3level.S b/arch/arm/mm/proc-v7-3level.S
> index 8de0f1d..78bd88c 100644
> --- a/arch/arm/mm/proc-v7-3level.S
> +++ b/arch/arm/mm/proc-v7-3level.S
> @@ -39,6 +39,22 @@
>  #define TTB_FLAGS_SMP	(TTB_IRGN_WBWA|TTB_S|TTB_RGN_OC_WBWA)
>  #define PMD_FLAGS_SMP	(PMD_SECT_WBWA|PMD_SECT_S)
>  
> +#define rzero	r3
> +#ifndef CONFIG_ARM_LPAE
> +#  define rpgdl	r0
> +#  define rpgdh	rzero
> +#  define rmm	r1
> +#else
> +#  define rmm	r2
> +#ifndef __ARMEB__
> +#  define rpgdl	r0
> +#  define rpgdh	r1
> +#else
> +#  define rpgdl	r1
> +#  define rpgdh	r0
> +#endif
> +#endif

Given proc-v7-3level.S is used only when CONFIG_ARM_LPAE is defined, you 
shouldn't need all the above.

>  /*
>   * cpu_v7_switch_mm(pgd_phys, tsk)
>   *
> @@ -47,10 +63,12 @@
>   */
>  ENTRY(cpu_v7_switch_mm)
>  #ifdef CONFIG_MMU
> -	ldr	r1, [r1, #MM_CONTEXT_ID]	@ get mm->context.id
> -	and	r3, r1, #0xff
> -	mov	r3, r3, lsl #(48 - 32)		@ ASID
> -	mcrr	p15, 0, r0, r3, c2		@ set TTB 0
> +	mov	rzero, #0
> +	ldr	rmm, [rmm, #MM_CONTEXT_ID]	@ get mm->context.id
> +	and	rmm, rmm, #0xff
> +	mov	rmm, rmm, lsl #(48 - 32)	@ ASID
> +	orr	rpgdh, rpgdh, rmm		@ upper 32-bits of pgd phys
> +	mcrr	p15, 0, rpgdl, rpgdh, c2	@ set TTB 0
>  	isb
>  #endif
>  	mov	pc, lr
> -- 
> 1.7.9.5
>