[PATCH] riscv: Repeat virtio scan

[PATCH] riscv: Repeat virtio scan

[Łukasz Stelmach]

The first time virtio_init() gets called from board_init() PCI isn't
ready. Thus any virtio-over-PCI (e.g. network interfaces) devices can't
be detected and used without additional `virtio scan` scan in the shell
or a script.

Signed-off-by: Łukasz Stelmach <l.stelmach@samsung.com>
---
The patch works for my but:

a) maybe virtio_init() should called only from board_init() the same
   way as on ARM?

b) can a repeated virtio_init() break already detected/initialized
   devices?

 board/emulation/qemu-riscv/qemu-riscv.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/board/emulation/qemu-riscv/qemu-riscv.c b/board/emulation/qemu-riscv/qemu-riscv.c
index 181abbbf97d..567b9dc6170 100644
--- a/board/emulation/qemu-riscv/qemu-riscv.c
+++ b/board/emulation/qemu-riscv/qemu-riscv.c
@@ -46,6 +46,9 @@ int board_late_init(void)
 	if (CONFIG_IS_ENABLED(USB_KEYBOARD))
 		usb_init();
 
+	/* Repeat virtio scan to detect PCI attached virtio devices. */
+	virtio_init();
+
 	return 0;
 }
 
-- 
2.39.2

Re: [PATCH] riscv: Repeat virtio scan

[Leo Liang]

Hi Łukasz,

On Mon, Feb 19, 2024 at 01:41:39PM +0100, Łukasz Stelmach wrote:
> The first time virtio_init() gets called from board_init() PCI isn't
> ready. Thus any virtio-over-PCI (e.g. network interfaces) devices can't
> be detected and used without additional `virtio scan` scan in the shell
> or a script.
> 
> Signed-off-by: Łukasz Stelmach <l.stelmach@samsung.com>
> ---
> The patch works for my but:
> 
> a) maybe virtio_init() should called only from board_init() the same
>    way as on ARM?
> b) can a repeated virtio_init() break already detected/initialized
>    devices?
> 

A repeated virtio_init() call would not break the already probed devices.
But we should prevent this redundancy by moving the virtio_init() call to
board_late_init() like what this commit[1] does for ARM.

Could you send a v2 to move the virtio_init() into board_late_init() ?

[1] https://patchwork.ozlabs.org/project/uboot/patch/20201230135712.5289-3-sughosh.ganu@linaro.org/
    e1ee06dde7 ("qemu: arm: Initialise virtio devices in board_late_init")

Best regards,
Leo

>  board/emulation/qemu-riscv/qemu-riscv.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/board/emulation/qemu-riscv/qemu-riscv.c b/board/emulation/qemu-riscv/qemu-riscv.c
> index 181abbbf97d..567b9dc6170 100644
> --- a/board/emulation/qemu-riscv/qemu-riscv.c
> +++ b/board/emulation/qemu-riscv/qemu-riscv.c
> @@ -46,6 +46,9 @@ int board_late_init(void)
>  	if (CONFIG_IS_ENABLED(USB_KEYBOARD))
>  		usb_init();
>  
> +	/* Repeat virtio scan to detect PCI attached virtio devices. */
> +	virtio_init();
> +
>  	return 0;
>  }
>