[v1] hw/riscv/virt: Add serial alias in DTB

[RFC PATCH] hw/riscv/virt: Add serial alias in DTB

Posted by Vasilis Liaskovitis 2 weeks, 6 days ago

This patch adds an "aliases" node with a "serial0" entry for the
single UART in the riscv64 virt machine.

This was requested in Gitlab #2774. However, since the machine only
has one UART at the moment, it's not clear that this addition makes
sense.

Fixes: https://gitlab.com/qemu-project/qemu/-/issues/2774
Signed-off-by: Vasilis Liaskovitis <vliaskovitis@suse.com>
---
 hw/riscv/virt.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/hw/riscv/virt.c b/hw/riscv/virt.c
index 2bc5a9dd98..67b80e9430 100644
--- a/hw/riscv/virt.c
+++ b/hw/riscv/virt.c
@@ -971,6 +971,8 @@ static void create_fdt_uart(RISCVVirtState *s, const MemMapEntry *memmap,
     }
 
     qemu_fdt_setprop_string(ms->fdt, "/chosen", "stdout-path", name);
+    qemu_fdt_add_subnode(ms->fdt, "/aliases");
+    qemu_fdt_setprop_string(ms->fdt, "/aliases", "serial0", name);
 }
 
 static void create_fdt_rtc(RISCVVirtState *s, const MemMapEntry *memmap,
-- 
2.46.0

Re: [RFC PATCH] hw/riscv/virt: Add serial alias in DTB

Posted by Andrew Jones 2 weeks, 6 days ago

On Thu, Jan 16, 2025 at 09:46:29AM +0100, Vasilis Liaskovitis wrote:
> This patch adds an "aliases" node with a "serial0" entry for the
> single UART in the riscv64 virt machine.
> 
> This was requested in Gitlab #2774. However, since the machine only
> has one UART at the moment, it's not clear that this addition makes
> sense.
> 
> Fixes: https://gitlab.com/qemu-project/qemu/-/issues/2774

s/Fixes/Resolves/ (see docs/devel/submitting-a-patch.rst)

> Signed-off-by: Vasilis Liaskovitis <vliaskovitis@suse.com>
> ---
>  hw/riscv/virt.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/hw/riscv/virt.c b/hw/riscv/virt.c
> index 2bc5a9dd98..67b80e9430 100644
> --- a/hw/riscv/virt.c
> +++ b/hw/riscv/virt.c
> @@ -971,6 +971,8 @@ static void create_fdt_uart(RISCVVirtState *s, const MemMapEntry *memmap,
>      }
>  
>      qemu_fdt_setprop_string(ms->fdt, "/chosen", "stdout-path", name);
> +    qemu_fdt_add_subnode(ms->fdt, "/aliases");

create_fdt_uart() is called at machine-done time, so we should create the
/aliases node in create_fdt() in case we ever have other uses for it.

> +    qemu_fdt_setprop_string(ms->fdt, "/aliases", "serial0", name);
>  }
>  
>  static void create_fdt_rtc(RISCVVirtState *s, const MemMapEntry *memmap,
> -- 
> 2.46.0
>

Thanks,
drew

Re: [RFC PATCH] hw/riscv/virt: Add serial alias in DTB

Posted by Vasilis Liaskovitis 2 weeks, 5 days ago

On Thu, Jan 16, 2025 at 10:23:56AM +0100, Andrew Jones wrote:
> 
> s/Fixes/Resolves/ (see docs/devel/submitting-a-patch.rst)
> 
[..]
> >      qemu_fdt_setprop_string(ms->fdt, "/chosen", "stdout-path", name);
> > +    qemu_fdt_add_subnode(ms->fdt, "/aliases");
> 
> create_fdt_uart() is called at machine-done time, so we should create the
> /aliases node in create_fdt() in case we ever have other uses for it.

thanks for the review, I am sending a v2 with the changes.

- Vasilis