[PATCH v2] xen/iommu: smmu: Silence clang in arm_smmu_device_dt_probe()

[PATCH v2] xen/iommu: smmu: Silence clang in arm_smmu_device_dt_probe()

[Julien Grall]

From: Julien Grall <jgrall@amazon.com>

Clang 11 will throw the following error:

smmu.c:2284:18: error: cast to smaller integer type 'enum arm_smmu_arch_version' from 'const void *' [-Werror,-Wvoid-pointer-to-enum-cast]
        smmu->version = (enum arm_smmu_arch_version)of_id->data;
                        ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The error can be prevented by initially casting to (uintptr_t) and then
enum.

Signed-off-by: Julien Grall <jgrall@amazon.com>

---

Changes in v2:
    - Cast to (uintptr_t) rather than introduce separate pointer
    (requested by Andrew).

Only build tested
---
 xen/drivers/passthrough/arm/smmu.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/xen/drivers/passthrough/arm/smmu.c b/xen/drivers/passthrough/arm/smmu.c
index 20ac672e91b6..fab7be8b48bb 100644
--- a/xen/drivers/passthrough/arm/smmu.c
+++ b/xen/drivers/passthrough/arm/smmu.c
@@ -2382,7 +2382,7 @@ static int arm_smmu_device_dt_probe(struct platform_device *pdev)
 	smmu->dev = dev;
 
 	of_id = of_match_node(arm_smmu_of_match, dev->of_node);
-	smmu->version = (enum arm_smmu_arch_version)of_id->data;
+	smmu->version = (enum arm_smmu_arch_version)(uintptr_t)of_id->data;
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	smmu->base = devm_ioremap_resource(dev, res);
-- 
2.17.1

Re: [PATCH v2] xen/iommu: smmu: Silence clang in arm_smmu_device_dt_probe()

[Stefano Stabellini]

On Fri, 2 Apr 2021, Julien Grall wrote:
> From: Julien Grall <jgrall@amazon.com>
> 
> Clang 11 will throw the following error:
> 
> smmu.c:2284:18: error: cast to smaller integer type 'enum arm_smmu_arch_version' from 'const void *' [-Werror,-Wvoid-pointer-to-enum-cast]
>         smmu->version = (enum arm_smmu_arch_version)of_id->data;
>                         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> 
> The error can be prevented by initially casting to (uintptr_t) and then
> enum.
> 
> Signed-off-by: Julien Grall <jgrall@amazon.com>

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


> ---
> 
> Changes in v2:
>     - Cast to (uintptr_t) rather than introduce separate pointer
>     (requested by Andrew).
> 
> Only build tested
> ---
>  xen/drivers/passthrough/arm/smmu.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/xen/drivers/passthrough/arm/smmu.c b/xen/drivers/passthrough/arm/smmu.c
> index 20ac672e91b6..fab7be8b48bb 100644
> --- a/xen/drivers/passthrough/arm/smmu.c
> +++ b/xen/drivers/passthrough/arm/smmu.c
> @@ -2382,7 +2382,7 @@ static int arm_smmu_device_dt_probe(struct platform_device *pdev)
>  	smmu->dev = dev;
>  
>  	of_id = of_match_node(arm_smmu_of_match, dev->of_node);
> -	smmu->version = (enum arm_smmu_arch_version)of_id->data;
> +	smmu->version = (enum arm_smmu_arch_version)(uintptr_t)of_id->data;
>  
>  	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>  	smmu->base = devm_ioremap_resource(dev, res);
> -- 
> 2.17.1
> 

Re: [PATCH v2] xen/iommu: smmu: Silence clang in arm_smmu_device_dt_probe()

[Julien Grall]

Hi Stefano,

On 06/04/2021 23:02, Stefano Stabellini wrote:
> On Fri, 2 Apr 2021, Julien Grall wrote:
>> From: Julien Grall <jgrall@amazon.com>
>>
>> Clang 11 will throw the following error:
>>
>> smmu.c:2284:18: error: cast to smaller integer type 'enum arm_smmu_arch_version' from 'const void *' [-Werror,-Wvoid-pointer-to-enum-cast]
>>          smmu->version = (enum arm_smmu_arch_version)of_id->data;
>>                          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
>>
>> The error can be prevented by initially casting to (uintptr_t) and then
>> enum.
>>
>> Signed-off-by: Julien Grall <jgrall@amazon.com>
> 
> Acked-by: Stefano Stabellini <sstabellini@kernel.org>

Thanks! I have committed the patch.

Cheers,

-- 
Julien Grall