Re: [v4] PCI: cadence-ep: Fix the driver to send MSG TLP for INTx without data payload

[Manivannan Sadhasivam]

On Sat, Feb 15, 2025 at 12:57:24AM +0800, Hans Zhang wrote:
> Cadence reference manual cdn_pcie_gen4_hpa_axi_ips_ug_v1.04.pdf, section
> 9.1.7.1 'AXI Subordinate to PCIe Address Translation' mentions that
> axi_s_awaddr bits 16 when set, corresponds to MSG with data and when not
> set, MSG without data.
> 
> But the driver is doing the opposite and due to this, INTx is never
> received on the host. So fix the driver to reflect the documentation and
> also make INTx work.
> 
> Fixes: 37dddf14f1ae ("PCI: cadence: Add EndPoint Controller driver for Cadence PCIe controller")
> Signed-off-by: Hans Zhang <18255117159@xxxxxxx>

Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx>

- Mani

> ---
> Changes since v3:
> https://lore.kernel.org/linux-pci/20250207103923.32190-1-18255117159@xxxxxxx/
> 
> - Add Fixes: tag.
> - The patch subject and commit message were modified.
> 
> Changes since v1-v2:
> - Change email number and Signed-off-by
> ---
>  drivers/pci/controller/cadence/pcie-cadence-ep.c | 3 +--
>  drivers/pci/controller/cadence/pcie-cadence.h    | 2 +-
>  2 files changed, 2 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/pci/controller/cadence/pcie-cadence-ep.c b/drivers/pci/controller/cadence/pcie-cadence-ep.c
> index e0cc4560dfde..0bf4cde34f51 100644
> --- a/drivers/pci/controller/cadence/pcie-cadence-ep.c
> +++ b/drivers/pci/controller/cadence/pcie-cadence-ep.c
> @@ -352,8 +352,7 @@ static void cdns_pcie_ep_assert_intx(struct cdns_pcie_ep *ep, u8 fn, u8 intx,
>  	spin_unlock_irqrestore(&ep->lock, flags);
>  
>  	offset = CDNS_PCIE_NORMAL_MSG_ROUTING(MSG_ROUTING_LOCAL) |
> -		 CDNS_PCIE_NORMAL_MSG_CODE(msg_code) |
> -		 CDNS_PCIE_MSG_NO_DATA;
> +		 CDNS_PCIE_NORMAL_MSG_CODE(msg_code);
>  	writel(0, ep->irq_cpu_addr + offset);
>  }
>  
> diff --git a/drivers/pci/controller/cadence/pcie-cadence.h b/drivers/pci/controller/cadence/pcie-cadence.h
> index f5eeff834ec1..39ee9945c903 100644
> --- a/drivers/pci/controller/cadence/pcie-cadence.h
> +++ b/drivers/pci/controller/cadence/pcie-cadence.h
> @@ -246,7 +246,7 @@ struct cdns_pcie_rp_ib_bar {
>  #define CDNS_PCIE_NORMAL_MSG_CODE_MASK		GENMASK(15, 8)
>  #define CDNS_PCIE_NORMAL_MSG_CODE(code) \
>  	(((code) << 8) & CDNS_PCIE_NORMAL_MSG_CODE_MASK)
> -#define CDNS_PCIE_MSG_NO_DATA			BIT(16)
> +#define CDNS_PCIE_MSG_DATA			BIT(16)
>  
>  struct cdns_pcie;
>  
> 
> -- 
> 2.25.1
> 

-- 
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