Re: [PATCH v1 03/16] arm/vpl011: use vuart_ prefix in vpl011 public calls

["Orzel, Michal" <michal.orzel@xxxxxxx>]

On 24/06/2025 05:55, dmkhn@xxxxxxxxx wrote:
> From: Denis Mukhin <dmukhin@xxxxxxxx> 
> 
> Use generic names prefixed with 'vuart_' in public PL011 emulator data
> structures and functions.
> 
> No functional change intended.
> 
> Signed-off-by: Denis Mukhin <dmukhin@xxxxxxxx>
> ---
>  xen/arch/arm/dom0less-build.c     |  4 ++--
>  xen/arch/arm/domain.c             |  3 ++-
>  xen/arch/arm/domctl.c             | 14 +++++++------
>  xen/arch/arm/include/asm/vpl011.h | 20 ------------------
>  xen/arch/arm/vpl011.c             | 24 +++++++++++-----------
>  xen/drivers/char/console.c        |  6 ++----
>  xen/include/xen/vuart.h           | 34 ++++++++++++++++++++++++++++++-
>  7 files changed, 59 insertions(+), 46 deletions(-)
> 
> diff --git a/xen/arch/arm/dom0less-build.c b/xen/arch/arm/dom0less-build.c
> index 7c1b59750fb5..11b8498d3b22 100644
> --- a/xen/arch/arm/dom0less-build.c
> +++ b/xen/arch/arm/dom0less-build.c
> @@ -216,7 +216,7 @@ int __init init_vuart(struct domain *d, struct 
> kernel_info *kinfo,
As can be seen here ...

>       */
>      if ( kinfo->arch.vpl011 )
>      {
> -        rc = domain_vpl011_init(d, NULL);
> +        rc = vuart_init(d, NULL);
we end up with init_vuart() and vuart_init(). That's quite confusing. Maybe
domain_vuart_init() or alike?

>          if ( rc < 0 )
>              return rc;
>      }
> @@ -247,7 +247,7 @@ void __init arch_create_domUs(struct dt_device_node *node,
>           * d->arch.vpl011.irq. So the logic to find the vIRQ has to
>           * be hardcoded.
>           * The logic here shall be consistent with the one in
> -         * domain_vpl011_init().
> +         * vuart_init().
>           */
>          if ( flags & CDF_directmap )
>          {
> diff --git a/xen/arch/arm/domain.c b/xen/arch/arm/domain.c
> index be58a23dd725..68297e619bad 100644
> --- a/xen/arch/arm/domain.c
> +++ b/xen/arch/arm/domain.c
> @@ -11,6 +11,7 @@
>  #include <xen/sched.h>
>  #include <xen/softirq.h>
>  #include <xen/wait.h>
> +#include <xen/vuart.h>
>  
>  #include <asm/arm64/sve.h>
>  #include <asm/cpuerrata.h>
> @@ -1072,7 +1073,7 @@ int domain_relinquish_resources(struct domain *d)
>           * Release the resources allocated for vpl011 which were
>           * allocated via a DOMCTL call XEN_DOMCTL_vuart_op.
>           */
> -        domain_vpl011_deinit(d);
> +        vuart_exit(d);
IMO, deinit is more meaningful here.

>  
>  #ifdef CONFIG_IOREQ_SERVER
>          ioreq_server_destroy_all(d);
> diff --git a/xen/arch/arm/domctl.c b/xen/arch/arm/domctl.c
> index ad914c915f81..dde25ceff6d0 100644
> --- a/xen/arch/arm/domctl.c
> +++ b/xen/arch/arm/domctl.c
> @@ -14,6 +14,7 @@
>  #include <xen/mm.h>
>  #include <xen/sched.h>
>  #include <xen/types.h>
> +#include <xen/vuart.h>
>  #include <xsm/xsm.h>
>  #include <public/domctl.h>
>  
> @@ -30,10 +31,11 @@ static int handle_vuart_init(struct domain *d,
>                               struct xen_domctl_vuart_op *vuart_op)
>  {
>      int rc;
> -    struct vpl011_init_info info;
> -
> -    info.console_domid = vuart_op->console_domid;
> -    info.gfn = _gfn(vuart_op->gfn);
> +    struct vuart_params params = {
> +        .console_domid = vuart_op->console_domid,
> +        .gfn = _gfn(vuart_op->gfn),
> +        .evtchn = 0,
> +    };
>  
>      if ( d->creation_finished )
>          return -EPERM;
> @@ -41,10 +43,10 @@ static int handle_vuart_init(struct domain *d,
>      if ( vuart_op->type != XEN_DOMCTL_VUART_TYPE_VPL011 )
>          return -EOPNOTSUPP;
>  
> -    rc = domain_vpl011_init(d, &info);
> +    rc = vuart_init(d, &params);
>  
>      if ( !rc )
> -        vuart_op->evtchn = info.evtchn;
> +        vuart_op->evtchn = params.evtchn;
>  
>      return rc;
>  }
> diff --git a/xen/arch/arm/include/asm/vpl011.h 
> b/xen/arch/arm/include/asm/vpl011.h
> index be64883b8628..5c308cc8c148 100644
> --- a/xen/arch/arm/include/asm/vpl011.h
> +++ b/xen/arch/arm/include/asm/vpl011.h
> @@ -59,26 +59,6 @@ struct vpl011 {
>      evtchn_port_t evtchn;
>  };
>  
> -struct vpl011_init_info {
> -    domid_t console_domid;
> -    gfn_t gfn;
> -    evtchn_port_t evtchn;
> -};
> -
> -#ifdef CONFIG_HAS_VUART_PL011
> -int domain_vpl011_init(struct domain *d,
> -                       struct vpl011_init_info *info);
> -void domain_vpl011_deinit(struct domain *d);
> -int vpl011_rx_char_xen(struct domain *d, char c);
> -#else
> -static inline int domain_vpl011_init(struct domain *d,
> -                                     struct vpl011_init_info *info)
> -{
> -    return -ENOSYS;
> -}
> -
> -static inline void domain_vpl011_deinit(struct domain *d) { }
> -#endif
>  #endif  /* _VPL011_H_ */
>  
>  /*
> diff --git a/xen/arch/arm/vpl011.c b/xen/arch/arm/vpl011.c
> index cafc532cf028..2cf88a70ecdb 100644
> --- a/xen/arch/arm/vpl011.c
> +++ b/xen/arch/arm/vpl011.c
> @@ -134,7 +134,7 @@ static void vpl011_write_data_xen(struct domain *d, 
> uint8_t data)
>  
>  /*
>   * vpl011_read_data_xen reads data when the backend is xen. Characters
> - * are added to the vpl011 receive buffer by vpl011_rx_char_xen.
> + * are added to the vpl011 receive buffer by vuart_putchar.
>   */
>  static uint8_t vpl011_read_data_xen(struct domain *d)
>  {
> @@ -571,9 +571,9 @@ static void vpl011_data_avail(struct domain *d,
>  }
>  
>  /*
> - * vpl011_rx_char_xen adds a char to a domain's vpl011 receive buffer.
> + * vuart_putchar adds a char to a domain's vpl011 receive buffer.
>   */
> -int vpl011_rx_char_xen(struct domain *d, char c)
> +int vuart_putchar(struct domain *d, char c)
How can putchar refer to RX? By definition putchar() is used to print data to
STDOUT. Here we receive a character and put it in the RX FIFO.

~Michal