xen/arm: arm32: Allow Xen to boot on unidentified CPUs

[XEN v2] xen/arm: arm32: Allow Xen to boot on unidentified CPUs

Posted by Ayan Kumar Halder 2 years, 7 months ago

Currently if the processor id is not identified (ie it is missing in proc-v7.S)
, then Xen boot fails quite early.
We have removed this restriction as for some CPUs (eg Cortex-R52), there isn't
any special initialization required.

Signed-off-by: Ayan Kumar Halder <ayan.kumar.halder@amd.com>
---
Changes from -

v1 - "[PATCH v1] xen/arm: arm32: Add support to identify the Cortex-R52 processor"
No need to add R52 proc id and empty stubs as there is no cpu initialization
required.

 xen/arch/arm/arm32/head.S | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/xen/arch/arm/arm32/head.S b/xen/arch/arm/arm32/head.S
index f9f7be9588..3e88178552 100644
--- a/xen/arch/arm/arm32/head.S
+++ b/xen/arch/arm/arm32/head.S
@@ -324,7 +324,7 @@ cpu_init:
         PRINT("- Missing processor info: ")
         print_reg r4
         PRINT(" -\r\n")
-        b     fail
+        b     cpu_init_done
 1:
         /* Jump to cpu_init */
         ldr   r1, [r1, #PROCINFO_cpu_init]  /* r1 := vaddr(init func) */
-- 
2.25.1

Re: [XEN v2] xen/arm: arm32: Allow Xen to boot on unidentified CPUs

Posted by Stefano Stabellini 2 years, 7 months ago

On Mon, 26 Jun 2023, Ayan Kumar Halder wrote:
> Currently if the processor id is not identified (ie it is missing in proc-v7.S)
> , then Xen boot fails quite early.
> We have removed this restriction as for some CPUs (eg Cortex-R52), there isn't
> any special initialization required.
> 
> Signed-off-by: Ayan Kumar Halder <ayan.kumar.halder@amd.com>

Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>


> ---
> Changes from -
> 
> v1 - "[PATCH v1] xen/arm: arm32: Add support to identify the Cortex-R52 processor"
> No need to add R52 proc id and empty stubs as there is no cpu initialization
> required.
> 
>  xen/arch/arm/arm32/head.S | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/xen/arch/arm/arm32/head.S b/xen/arch/arm/arm32/head.S
> index f9f7be9588..3e88178552 100644
> --- a/xen/arch/arm/arm32/head.S
> +++ b/xen/arch/arm/arm32/head.S
> @@ -324,7 +324,7 @@ cpu_init:
>          PRINT("- Missing processor info: ")
>          print_reg r4
>          PRINT(" -\r\n")
> -        b     fail
> +        b     cpu_init_done
>  1:
>          /* Jump to cpu_init */
>          ldr   r1, [r1, #PROCINFO_cpu_init]  /* r1 := vaddr(init func) */
> -- 
> 2.25.1
> 
>

Re: [XEN v2] xen/arm: arm32: Allow Xen to boot on unidentified CPUs

Posted by Julien Grall 2 years, 7 months ago

Hi,

On 29/06/2023 00:00, Stefano Stabellini wrote:
> On Mon, 26 Jun 2023, Ayan Kumar Halder wrote:
>> Currently if the processor id is not identified (ie it is missing in proc-v7.S)
>> , then Xen boot fails quite early.
>> We have removed this restriction as for some CPUs (eg Cortex-R52), there isn't
>> any special initialization required.
>>
>> Signed-off-by: Ayan Kumar Halder <ayan.kumar.halder@amd.com>
> 
> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>

I have committed it.

Cheers,

-- 
Julien Grall