Re: [PATCH for-9.1 1/2] Revert "hw/riscv/virt.c: imsics DT: add '#msi-cells'"

[Daniel Henrique Barboza <dbarboza@ventanamicro.com>]

On 8/16/24 1:07 PM, Andrew Jones wrote:
> This reverts commit f42cdf2ea5b3a1dc369792d7acbf9cd3e5c90815.
> 
> Linux does not properly handle '#msi-cells=<0>' when searching for
> MSI controllers for PCI devices which results in the devices being
> unable to use MSIs. A patch for Linux has been sent[1] but until it,
> or something like it, is merged and in distro kernels we should stop
> adding the property. It's harmless to stop adding it since the
> absence of the property and a value of zero for the property mean
> the same thing according to the DT binding definition.
> 
> Link: https://lore.kernel.org/all/20240816124957.130017-2-ajones@ventanamicro.com/ # 1
> Signed-off-by: Andrew Jones <ajones@ventanamicro.com>
> ---

Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>


This is indeed a 9.1 fix. Thanks Drew for sending it.

We can discuss whether we should wrap this around the 'strict-dt' flag or not, but
that can wait for 9.2.


Thanks,

Daniel


>   hw/riscv/virt.c | 1 -
>   1 file changed, 1 deletion(-)
> 
> diff --git a/hw/riscv/virt.c b/hw/riscv/virt.c
> index 9981e0f6c9b9..cef41c150aaf 100644
> --- a/hw/riscv/virt.c
> +++ b/hw/riscv/virt.c
> @@ -552,7 +552,6 @@ static void create_fdt_one_imsic(RISCVVirtState *s, hwaddr base_addr,
>                             FDT_IMSIC_INT_CELLS);
>       qemu_fdt_setprop(ms->fdt, imsic_name, "interrupt-controller", NULL, 0);
>       qemu_fdt_setprop(ms->fdt, imsic_name, "msi-controller", NULL, 0);
> -    qemu_fdt_setprop_cell(ms->fdt, imsic_name, "#msi-cells", 0);
>       qemu_fdt_setprop(ms->fdt, imsic_name, "interrupts-extended",
>                        imsic_cells, ms->smp.cpus * sizeof(uint32_t) * 2);
>       qemu_fdt_setprop(ms->fdt, imsic_name, "reg", imsic_regs,