Re: [PATCH v4 2/3] PCI: dw-rockchip: Reorganize register and bitfield definitions

From: Wilfred Mallawa <wilfred.opensource@gmail.com>
To: Hans Zhang <18255117159@163.com>,
	lpieralisi@kernel.org, kw@linux.com,  bhelgaas@google.com,
	heiko@sntech.de
Cc: manivannan.sadhasivam@linaro.org, robh@kernel.org,
	jingoohan1@gmail.com, shawn.lin@rock-chips.com,
	linux-pci@vger.kernel.org,  linux-kernel@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org,
	 linux-rockchip@lists.infradead.org,
	Niklas Cassel <cassel@kernel.org>
Subject: Re: [PATCH v4 2/3] PCI: dw-rockchip: Reorganize register and bitfield definitions
Date: Mon, 28 Apr 2025 13:28:24 +1000	[thread overview]
Message-ID: <9e9ff312eb019bce9f6c31ebda4e1aa6b1a91f33.camel@gmail.com> (raw)
In-Reply-To: <20250427125316.99627-3-18255117159@163.com>

On Sun, 2025-04-27 at 20:53 +0800, Hans Zhang wrote:
> Register definitions were scattered with ambiguous names (e.g.,
> PCIE_RDLH_LINK_UP_CHGED in PCIE_CLIENT_INTR_STATUS_MISC) and lacked
> hierarchical grouping. Magic values for bit operations reduced code
> clarity.
> 
> Group registers and their associated bitfields logically. This
> improves
> maintainability and aligns the code with hardware documentation.
> 
> Signed-off-by: Hans Zhang <18255117159@163.com>
> Reviewed-by: Niklas Cassel <cassel@kernel.org>
> Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
> ---
>  drivers/pci/controller/dwc/pcie-dw-rockchip.c | 49 ++++++++++++-----
> --
>  1 file changed, 31 insertions(+), 18 deletions(-)
> 
> diff --git a/drivers/pci/controller/dwc/pcie-dw-rockchip.c
> b/drivers/pci/controller/dwc/pcie-dw-rockchip.c
> index e7d33d545d5b..a778f4f61595 100644
> --- a/drivers/pci/controller/dwc/pcie-dw-rockchip.c
> +++ b/drivers/pci/controller/dwc/pcie-dw-rockchip.c
> @@ -33,24 +33,37 @@
>  
>  #define to_rockchip_pcie(x) dev_get_drvdata((x)->dev)
>  
> -#define PCIE_CLIENT_RC_MODE		HIWORD_UPDATE_BIT(0x40)
> -#define PCIE_CLIENT_EP_MODE		HIWORD_UPDATE(0xf0, 0x0)
> -#define PCIE_CLIENT_ENABLE_LTSSM	HIWORD_UPDATE_BIT(0xc)
> -#define PCIE_CLIENT_DISABLE_LTSSM	HIWORD_UPDATE(0x0c, 0x8)
> -#define PCIE_CLIENT_INTR_STATUS_MISC	0x10
> -#define PCIE_CLIENT_INTR_MASK_MISC	0x24
> -#define PCIE_SMLH_LINKUP		BIT(16)
> -#define PCIE_RDLH_LINKUP		BIT(17)
> -#define PCIE_LINKUP			(PCIE_SMLH_LINKUP |
> PCIE_RDLH_LINKUP)
> -#define PCIE_RDLH_LINK_UP_CHGED		BIT(1)
> -#define PCIE_LINK_REQ_RST_NOT_INT	BIT(2)
> -#define PCIE_CLIENT_GENERAL_CONTROL	0x0
> +/* General Control Register */
> +#define PCIE_CLIENT_GENERAL_CON		0x0
> +#define  PCIE_CLIENT_RC_MODE		HIWORD_UPDATE_BIT(0x40)
> +#define  PCIE_CLIENT_EP_MODE		HIWORD_UPDATE(0xf0, 0x0)
> +#define  PCIE_CLIENT_ENABLE_LTSSM	HIWORD_UPDATE_BIT(0xc)
> +#define  PCIE_CLIENT_DISABLE_LTSSM	HIWORD_UPDATE(0x0c, 0x8)
> +
> +/* Interrupt Status Register Related to Legacy Interrupt */
>  #define PCIE_CLIENT_INTR_STATUS_LEGACY	0x8
> +
> +/* Interrupt Status Register Related to Miscellaneous Operation */
> +#define PCIE_CLIENT_INTR_STATUS_MISC	0x10
> +#define  PCIE_RDLH_LINK_UP_CHGED	BIT(1)
> +#define  PCIE_LINK_REQ_RST_NOT_INT	BIT(2)
> +
> +/* Interrupt Mask Register Related to Legacy Interrupt */
>  #define PCIE_CLIENT_INTR_MASK_LEGACY	0x1c
> +
> +/* Interrupt Mask Register Related to Miscellaneous Operation */
> +#define PCIE_CLIENT_INTR_MASK_MISC	0x24
> +
> +/* Hot Reset Control Register */
>  #define PCIE_CLIENT_HOT_RESET_CTRL	0x180
> +#define  PCIE_LTSSM_ENABLE_ENHANCE	BIT(4)
> +
> +/* LTSSM Status Register */
>  #define PCIE_CLIENT_LTSSM_STATUS	0x300
> -#define PCIE_LTSSM_ENABLE_ENHANCE	BIT(4)
> -#define PCIE_LTSSM_STATUS_MASK		GENMASK(5, 0)
> +#define  PCIE_SMLH_LINKUP		BIT(16)
> +#define  PCIE_RDLH_LINKUP		BIT(17)
> +#define  PCIE_LINKUP			(PCIE_SMLH_LINKUP |
> PCIE_RDLH_LINKUP)
> +#define  PCIE_LTSSM_STATUS_MASK		GENMASK(5, 0)
>  
>  struct rockchip_pcie {
>  	struct dw_pcie pci;
> @@ -161,13 +174,13 @@ static u32 rockchip_pcie_get_ltssm(struct
> rockchip_pcie *rockchip)
>  static void rockchip_pcie_enable_ltssm(struct rockchip_pcie
> *rockchip)
>  {
>  	rockchip_pcie_writel_apb(rockchip, PCIE_CLIENT_ENABLE_LTSSM,
> -				 PCIE_CLIENT_GENERAL_CONTROL);
> +				 PCIE_CLIENT_GENERAL_CON);
>  }
>  
>  static void rockchip_pcie_disable_ltssm(struct rockchip_pcie
> *rockchip)
>  {
>  	rockchip_pcie_writel_apb(rockchip,
> PCIE_CLIENT_DISABLE_LTSSM,
> -				 PCIE_CLIENT_GENERAL_CONTROL);
> +				 PCIE_CLIENT_GENERAL_CON);
>  }
>  
>  static int rockchip_pcie_link_up(struct dw_pcie *pci)
> @@ -516,7 +529,7 @@ static int rockchip_pcie_configure_rc(struct
> platform_device *pdev,
>  	rockchip_pcie_writel_apb(rockchip, val,
> PCIE_CLIENT_HOT_RESET_CTRL);
>  
>  	rockchip_pcie_writel_apb(rockchip, PCIE_CLIENT_RC_MODE,
> -				 PCIE_CLIENT_GENERAL_CONTROL);
> +				 PCIE_CLIENT_GENERAL_CON);
>  
>  	pp = &rockchip->pci.pp;
>  	pp->ops = &rockchip_pcie_host_ops;
> @@ -562,7 +575,7 @@ static int rockchip_pcie_configure_ep(struct
> platform_device *pdev,
>  	rockchip_pcie_writel_apb(rockchip, val,
> PCIE_CLIENT_HOT_RESET_CTRL);
>  
>  	rockchip_pcie_writel_apb(rockchip, PCIE_CLIENT_EP_MODE,
> -				 PCIE_CLIENT_GENERAL_CONTROL);
> +				 PCIE_CLIENT_GENERAL_CON);
>  
>  	rockchip->pci.ep.ops = &rockchip_pcie_ep_ops;
>  	rockchip->pci.ep.page_size = SZ_64K;
Reviewed-by: Wilfred Mallawa <wilfred.mallawa@wdc.com>