Re: [PATCH v6 12/13] xen/arm: Suspend/resume IOMMU on Xen suspend/resume

[Volodymyr Babchuk <Volodymyr_Babchuk@epam.com>]

Hi,

Mykola Kvach <xakep.amatop@gmail.com> writes:

> From: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
>
> This is done using generic iommu_suspend/resume functions that cause
> IOMMU driver specific suspend/resume handlers to be called for enabled
> IOMMU (if one has suspend/resume driver handlers implemented).
>
> Signed-off-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
> Signed-off-by: Mykola Kvach <mykola_kvach@epam.com>

Reviewed-by: Volodymyr Babchuk <volodymyr_babchuk@epam.com>

> ---
> Changes in V6:
> - Drop iommu_enabled check from host system suspend.
> ---
>  xen/arch/arm/suspend.c                | 11 +++++++++++
>  xen/drivers/passthrough/arm/smmu-v3.c | 10 ++++++++++
>  xen/drivers/passthrough/arm/smmu.c    | 10 ++++++++++
>  3 files changed, 31 insertions(+)
>
> diff --git a/xen/arch/arm/suspend.c b/xen/arch/arm/suspend.c
> index 35b20581f1..f3a3b831c5 100644
> --- a/xen/arch/arm/suspend.c
> +++ b/xen/arch/arm/suspend.c
> @@ -5,6 +5,7 @@
>  
>  #include <xen/console.h>
>  #include <xen/cpu.h>
> +#include <xen/iommu.h>
>  #include <xen/llc-coloring.h>
>  #include <xen/sched.h>
>  #include <xen/tasklet.h>
> @@ -62,6 +63,13 @@ static void cf_check system_suspend(void *data)
>  
>      time_suspend();
>  
> +    status = iommu_suspend();
> +    if ( status )
> +    {
> +        system_state = SYS_STATE_resume;
> +        goto resume_time;
> +    }
> +
>      console_start_sync();
>      status = console_suspend();
>      if ( status )
> @@ -118,6 +126,9 @@ static void cf_check system_suspend(void *data)
>      console_resume();
>      console_end_sync();
>  
> +    iommu_resume();
> +
> + resume_time:
>      time_resume();
>  
>   resume_nonboot_cpus:
> diff --git a/xen/drivers/passthrough/arm/smmu-v3.c b/xen/drivers/passthrough/arm/smmu-v3.c
> index 81071f4018..f887faf7dc 100644
> --- a/xen/drivers/passthrough/arm/smmu-v3.c
> +++ b/xen/drivers/passthrough/arm/smmu-v3.c
> @@ -2854,6 +2854,13 @@ static void arm_smmu_iommu_xen_domain_teardown(struct domain *d)
>  	xfree(xen_domain);
>  }
>  
> +#ifdef CONFIG_SYSTEM_SUSPEND
> +static int arm_smmu_suspend(void)
> +{
> +	return -ENOSYS;
> +}
> +#endif
> +
>  static const struct iommu_ops arm_smmu_iommu_ops = {
>  	.page_sizes		= PAGE_SIZE_4K,
>  	.init			= arm_smmu_iommu_xen_domain_init,
> @@ -2866,6 +2873,9 @@ static const struct iommu_ops arm_smmu_iommu_ops = {
>  	.unmap_page		= arm_iommu_unmap_page,
>  	.dt_xlate		= arm_smmu_dt_xlate,
>  	.add_device		= arm_smmu_add_device,
> +#ifdef CONFIG_SYSTEM_SUSPEND
> +	.suspend		= arm_smmu_suspend,
> +#endif
>  };
>  
>  static __init int arm_smmu_dt_init(struct dt_device_node *dev,
> diff --git a/xen/drivers/passthrough/arm/smmu.c b/xen/drivers/passthrough/arm/smmu.c
> index 22d306d0cb..45f29ef8ec 100644
> --- a/xen/drivers/passthrough/arm/smmu.c
> +++ b/xen/drivers/passthrough/arm/smmu.c
> @@ -2947,6 +2947,13 @@ static void arm_smmu_iommu_domain_teardown(struct domain *d)
>  	xfree(xen_domain);
>  }
>  
> +#ifdef CONFIG_SYSTEM_SUSPEND
> +static int arm_smmu_suspend(void)
> +{
> +	return -ENOSYS;
> +}
> +#endif
> +
>  static const struct iommu_ops arm_smmu_iommu_ops = {
>      .page_sizes = PAGE_SIZE_4K,
>      .init = arm_smmu_iommu_domain_init,
> @@ -2960,6 +2967,9 @@ static const struct iommu_ops arm_smmu_iommu_ops = {
>      .map_page = arm_iommu_map_page,
>      .unmap_page = arm_iommu_unmap_page,
>      .dt_xlate = arm_smmu_dt_xlate_generic,
> +#ifdef CONFIG_SYSTEM_SUSPEND
> +    .suspend = arm_smmu_suspend,
> +#endif
>  };
>  
>  static struct arm_smmu_device *find_smmu(const struct device *dev)

-- 
WBR, Volodymyr