Subject: Re: [PATCHv7 02/12] PCI: designware-ep: Add the doorbell mode of MSI-X in EP mode

From: Rob Herring <[email-masked]>
Date: Thu, 10 Sep 2020 11:58:04 -0600

On Tue, Aug 11, 2020 at 05:54:31PM +0800, Zhiqiang Hou wrote:
> From: Xiaowei Bao <[email-masked]>
> 
> Add the doorbell mode of MSI-X in DWC EP driver.
> 
> Signed-off-by: Xiaowei Bao <[email-masked]>
> Reviewed-by: Andrew Murray <[email-masked]>
> Signed-off-by: Hou Zhiqiang <[email-masked]>
> ---
> V7:
>  - Rebase the patch without functionality change.
> 
>  drivers/pci/controller/dwc/pcie-designware-ep.c | 14 ++++++++++++++
>  drivers/pci/controller/dwc/pcie-designware.h    | 12 ++++++++++++
>  2 files changed, 26 insertions(+)
> 
> diff --git a/drivers/pci/controller/dwc/pcie-designware-ep.c b/drivers/pci/controller/dwc/pcie-designware-ep.c
> index e5bd3a5ef380..e76b504ed465 100644
> --- a/drivers/pci/controller/dwc/pcie-designware-ep.c
> +++ b/drivers/pci/controller/dwc/pcie-designware-ep.c
> @@ -471,6 +471,20 @@ int dw_pcie_ep_raise_msi_irq(struct dw_pcie_ep *ep, u8 func_no,
>  	return 0;
>  }
>  
> +int dw_pcie_ep_raise_msix_irq_doorbell(struct dw_pcie_ep *ep, u8 func_no,

return void. It never has an error.

It could also just be an inline function.

> +				       u16 interrupt_num)
> +{
> +	struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
> +	u32 msg_data;
> +
> +	msg_data = (func_no << PCIE_MSIX_DOORBELL_PF_SHIFT) |
> +		   (interrupt_num - 1);
> +
> +	dw_pcie_writel_dbi(pci, PCIE_MSIX_DOORBELL, msg_data);
> +
> +	return 0;
> +}
> +
>  int dw_pcie_ep_raise_msix_irq(struct dw_pcie_ep *ep, u8 func_no,
>  			      u16 interrupt_num)
>  {
> diff --git a/drivers/pci/controller/dwc/pcie-designware.h b/drivers/pci/controller/dwc/pcie-designware.h
> index 89f8271ec5ee..745b4938225a 100644
> --- a/drivers/pci/controller/dwc/pcie-designware.h
> +++ b/drivers/pci/controller/dwc/pcie-designware.h
> @@ -97,6 +97,9 @@
>  #define PCIE_MISC_CONTROL_1_OFF		0x8BC
>  #define PCIE_DBI_RO_WR_EN		BIT(0)
>  
> +#define PCIE_MSIX_DOORBELL		0x948
> +#define PCIE_MSIX_DOORBELL_PF_SHIFT	24
> +
>  #define PCIE_PL_CHK_REG_CONTROL_STATUS			0xB20
>  #define PCIE_PL_CHK_REG_CHK_REG_START			BIT(0)
>  #define PCIE_PL_CHK_REG_CHK_REG_CONTINUOUS		BIT(1)
> @@ -434,6 +437,8 @@ int dw_pcie_ep_raise_msi_irq(struct dw_pcie_ep *ep, u8 func_no,
>  			     u8 interrupt_num);
>  int dw_pcie_ep_raise_msix_irq(struct dw_pcie_ep *ep, u8 func_no,
>  			     u16 interrupt_num);
> +int dw_pcie_ep_raise_msix_irq_doorbell(struct dw_pcie_ep *ep, u8 func_no,
> +				       u16 interrupt_num);
>  void dw_pcie_ep_reset_bar(struct dw_pcie *pci, enum pci_barno bar);
>  #else
>  static inline void dw_pcie_ep_linkup(struct dw_pcie_ep *ep)
> @@ -475,6 +480,13 @@ static inline int dw_pcie_ep_raise_msix_irq(struct dw_pcie_ep *ep, u8 func_no,
>  	return 0;
>  }
>  
> +static inline int dw_pcie_ep_raise_msix_irq_doorbell(struct dw_pcie_ep *ep,
> +						     u8 func_no,
> +						     u16 interrupt_num)
> +{
> +	return 0;
> +}
> +
>  static inline void dw_pcie_ep_reset_bar(struct dw_pcie *pci, enum pci_barno bar)
>  {
>  }
> -- 
> 2.17.1
>