[PATCH V2] xen/arm64: Use virtual address when setting up early_printk fixmap

[PATCH V2] xen/arm64: Use virtual address when setting up early_printk fixmap

[Chen Baozi]

We have already had the boot pagetable when reaching the point
of early_printk fixmap setup. Thus there is no longer necessary
to calculate physical address of xen_fixmap.

Signed-off-by: Chen Baozi <baozich@gmail.com>
---
 xen/arch/arm/arm64/head.S | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/xen/arch/arm/arm64/head.S b/xen/arch/arm/arm64/head.S
index 75b7ee1..9ed9a93 100644
--- a/xen/arch/arm/arm64/head.S
+++ b/xen/arch/arm/arm64/head.S
@@ -519,8 +519,7 @@ paging:
         cbnz  x22, 1f
 
         /* Add UART to the fixmap table */
-        ldr   x1, =xen_fixmap
-        add   x1, x1, x20            /* x1 := paddr (xen_fixmap) */
+        ldr   x1, =xen_fixmap        /* x1 := vaddr (xen_fixmap) */
         lsr   x2, x23, #THIRD_SHIFT
         lsl   x2, x2, #THIRD_SHIFT   /* 4K aligned paddr of UART */
         mov   x3, #PT_DEV_L3
-- 
2.1.4

Re: [PATCH V2] xen/arm64: Use virtual address when setting up early_printk fixmap

[Julien Grall]

Hi Chen,

On 07/04/15 12:24, Chen Baozi wrote:
> We have already had the boot pagetable when reaching the point

s/had/added/ ?

> of early_printk fixmap setup. Thus there is no longer necessary

s/there is/it is/ ?

> to calculate physical address of xen_fixmap.
> 
> Signed-off-by: Chen Baozi <baozich@gmail.com>

Other than the possible typoes above:

Reviewed-by: Julien Grall <julien.grall@citrix.com>

Regards,

-- 
Julien Grall

Re: [PATCH V2] xen/arm64: Use virtual address when setting up early_printk fixmap

[Ian Campbell]

On Wed, 2015-04-08 at 12:33 +0100, Julien Grall wrote:
> Hi Chen,
> 
> On 07/04/15 12:24, Chen Baozi wrote:
> > We have already had the boot pagetable when reaching the point
> 
> s/had/added/ ?

I think "switched too" is what was meant and more correct.

> > of early_printk fixmap setup. Thus there is no longer necessary
> 
> s/there is/it is/ ?

Yes.

> > to calculate physical address of xen_fixmap.
> > 
> > Signed-off-by: Chen Baozi <baozich@gmail.com>
> 
> Other than the possible typoes above:
> 
> Reviewed-by: Julien Grall <julien.grall@citrix.com>

Acked-by: Ian Campbell <ian.campbell@citrix.com>

If it is confirmed that I got the correct meaning in the first one I can
fix both on commit.

Ian.

Re: [PATCH V2] xen/arm64: Use virtual address when setting up early_printk fixmap

[Chen Baozi]

On Wed, Apr 15, 2015 at 03:41:44PM +0100, Ian Campbell wrote:
> On Wed, 2015-04-08 at 12:33 +0100, Julien Grall wrote:
> > Hi Chen,
> > 
> > On 07/04/15 12:24, Chen Baozi wrote:
> > > We have already had the boot pagetable when reaching the point
> > 
> > s/had/added/ ?
> 
> I think "switched too" is what was meant and more correct.
> 

So do I ;-)

> > > of early_printk fixmap setup. Thus there is no longer necessary
> > 
> > s/there is/it is/ ?
> 
> Yes.
> 
> > > to calculate physical address of xen_fixmap.
> > > 
> > > Signed-off-by: Chen Baozi <baozich@gmail.com>
> > 
> > Other than the possible typoes above:
> > 
> > Reviewed-by: Julien Grall <julien.grall@citrix.com>
> 
> Acked-by: Ian Campbell <ian.campbell@citrix.com>
> 
> If it is confirmed that I got the correct meaning in the first one I can
> fix both on commit.

Yes, please. Thanks.

Baozi

Re: [PATCH V2] xen/arm64: Use virtual address when setting up early_printk fixmap

[Ian Campbell]

On Fri, 2015-04-17 at 19:39 +0800, Chen Baozi wrote:
> > 
> > Acked-by: Ian Campbell <ian.campbell@citrix.com>
> > 
> > If it is confirmed that I got the correct meaning in the first one I can
> > fix both on commit.
> 
> Yes, please. Thanks.

Done and pushed, thanks.

Re: [PATCH V2] xen/arm64: Use virtual address when setting up early_printk fixmap

[Julien Grall]

Hi Ian,

On 07/04/15 12:24, Chen Baozi wrote:
> We have already had the boot pagetable when reaching the point
> of early_printk fixmap setup. Thus there is no longer necessary
> to calculate physical address of xen_fixmap.
> 
> Signed-off-by: Chen Baozi <baozich@gmail.com>

This patch has been fully ack and Chen agreed that you fix the typoes.
Can you commit it?

Cheers,

> ---
>  xen/arch/arm/arm64/head.S | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/xen/arch/arm/arm64/head.S b/xen/arch/arm/arm64/head.S
> index 75b7ee1..9ed9a93 100644
> --- a/xen/arch/arm/arm64/head.S
> +++ b/xen/arch/arm/arm64/head.S
> @@ -519,8 +519,7 @@ paging:
>          cbnz  x22, 1f
>  
>          /* Add UART to the fixmap table */
> -        ldr   x1, =xen_fixmap
> -        add   x1, x1, x20            /* x1 := paddr (xen_fixmap) */
> +        ldr   x1, =xen_fixmap        /* x1 := vaddr (xen_fixmap) */
>          lsr   x2, x23, #THIRD_SHIFT
>          lsl   x2, x2, #THIRD_SHIFT   /* 4K aligned paddr of UART */
>          mov   x3, #PT_DEV_L3
> 


-- 
Julien Grall