Re: [PATCH] hw/pci-bridge/pci_expander_bridge: Fix HDM passthrough condition

["Zhijian Li (Fujitsu)" <lizhijian@fujitsu.com>]

Ping

Only if (dsp_count==1 && hdm_for_passthrough==true), the QEMU shouldn't implement
the HDM decodder for the Host-bridge.

But previous code didn't follow this.

Thanks
Zhijian

On 23/03/2025 16:04, Li Zhijian wrote:
> Reverse the logical condition for HDM passthrough support in
> pci_expander_bridge. This patch ensures the HDM passthrough condition
> is evaluated only when hdm_for_passthrough is set to true, aligning
> behavior with intended semantics and comments.
> 
> Signed-off-by: Li Zhijian <lizhijian@fujitsu.com>
> ---
> 
> This change corrects what appears to be a previous mistake in logic
> regarding HDM passthrough conditions.
> ---
>   hw/pci-bridge/pci_expander_bridge.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/hw/pci-bridge/pci_expander_bridge.c b/hw/pci-bridge/pci_expander_bridge.c
> index 3396ab4bdd..25f8922d76 100644
> --- a/hw/pci-bridge/pci_expander_bridge.c
> +++ b/hw/pci-bridge/pci_expander_bridge.c
> @@ -307,7 +307,7 @@ static void pxb_cxl_dev_reset(DeviceState *dev)
>        * The CXL specification allows for host bridges with no HDM decoders
>        * if they only have a single root port.
>        */
> -    if (!PXB_CXL_DEV(dev)->hdm_for_passthrough) {
> +    if (PXB_CXL_DEV(dev)->hdm_for_passthrough) {
>           dsp_count = pcie_count_ds_ports(hb->bus);
>       }
>       /* Initial reset will have 0 dsp so wait until > 0 */