[v1] Remaining patches for dynamic node programming using overlay dtbo

[PATCH 04/15] tools/libs/light: Always enable IOMMU

Posted by Henry Wang 1 year, 9 months ago

From: Vikram Garhwal <fnu.vikram@xilinx.com>

For overlay with iommu functionality to work with running VMs, we need
to enable IOMMU when iomem presents for the domains.

Signed-off-by: Vikram Garhwal <fnu.vikram@xilinx.com>
Signed-off-by: Henry Wang <xin.wang2@amd.com>
---
 tools/libs/light/libxl_arm.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/tools/libs/light/libxl_arm.c b/tools/libs/light/libxl_arm.c
index 1cb89fa584..dd5c9f4917 100644
--- a/tools/libs/light/libxl_arm.c
+++ b/tools/libs/light/libxl_arm.c
@@ -222,6 +222,12 @@ int libxl__arch_domain_prepare_config(libxl__gc *gc,
         config->arch.sve_vl = d_config->b_info.arch_arm.sve_vl / 128U;
     }
 
+#ifdef LIBXL_HAVE_DT_OVERLAY
+    if (d_config->b_info.num_iomem) {
+        config->flags |= XEN_DOMCTL_CDF_iommu;
+    }
+#endif
+
     return 0;
 }
 
-- 
2.34.1

Re: [PATCH 04/15] tools/libs/light: Always enable IOMMU

Posted by Anthony PERARD 1 year, 9 months ago

On Wed, Apr 24, 2024 at 11:34:38AM +0800, Henry Wang wrote:
> For overlay with iommu functionality to work with running VMs, we need
> to enable IOMMU when iomem presents for the domains.
> 
> Signed-off-by: Vikram Garhwal <fnu.vikram@xilinx.com>
> Signed-off-by: Henry Wang <xin.wang2@amd.com>
> ---
>  tools/libs/light/libxl_arm.c | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/tools/libs/light/libxl_arm.c b/tools/libs/light/libxl_arm.c
> index 1cb89fa584..dd5c9f4917 100644
> --- a/tools/libs/light/libxl_arm.c
> +++ b/tools/libs/light/libxl_arm.c
> @@ -222,6 +222,12 @@ int libxl__arch_domain_prepare_config(libxl__gc *gc,
>          config->arch.sve_vl = d_config->b_info.arch_arm.sve_vl / 128U;
>      }
>  
> +#ifdef LIBXL_HAVE_DT_OVERLAY

libxl_arm.c is only build on Arm, so this should be defined, so no need
to check.

> +    if (d_config->b_info.num_iomem) {
> +        config->flags |= XEN_DOMCTL_CDF_iommu;

Is this doing the same thing as the previous patch?

Thanks,

-- 
Anthony PERARD

Re: [PATCH 04/15] tools/libs/light: Always enable IOMMU

Posted by Henry Wang 1 year, 9 months ago

Hi Anthony,

On 5/1/2024 9:47 PM, Anthony PERARD wrote:
> On Wed, Apr 24, 2024 at 11:34:38AM +0800, Henry Wang wrote:
>> For overlay with iommu functionality to work with running VMs, we need
>> to enable IOMMU when iomem presents for the domains.
>>
>> Signed-off-by: Vikram Garhwal <fnu.vikram@xilinx.com>
>> Signed-off-by: Henry Wang <xin.wang2@amd.com>
>> ---
>>   tools/libs/light/libxl_arm.c | 6 ++++++
>>   1 file changed, 6 insertions(+)
>>
>> diff --git a/tools/libs/light/libxl_arm.c b/tools/libs/light/libxl_arm.c
>> index 1cb89fa584..dd5c9f4917 100644
>> --- a/tools/libs/light/libxl_arm.c
>> +++ b/tools/libs/light/libxl_arm.c
>> @@ -222,6 +222,12 @@ int libxl__arch_domain_prepare_config(libxl__gc *gc,
>>           config->arch.sve_vl = d_config->b_info.arch_arm.sve_vl / 128U;
>>       }
>>   
>> +#ifdef LIBXL_HAVE_DT_OVERLAY
> libxl_arm.c is only build on Arm, so this should be defined, so no need
> to check.

Ah sure, I was just thought in the future RISC-V/PPC may have the same, 
but you are correct. I will remove the check.

>> +    if (d_config->b_info.num_iomem) {
>> +        config->flags |= XEN_DOMCTL_CDF_iommu;
> Is this doing the same thing as the previous patch?

I think so, yes, we need the IOMMU flag to be set if we want to assign a 
device from a DT node protected by IOMMU.

Kind regards,
Henry

>
> Thanks,
>