Re: [PATCH v4 09/13] PCI: dw-rockchip: Refactor the driver to prepare for EP mode

[Manivannan Sadhasivam <mani@kernel.org>]

On Wed, May 29, 2024 at 10:29:03AM +0200, Niklas Cassel wrote:
> This refactors the driver to prepare for EP mode.
> Add of-match data to the existing compatible, and explicitly define it as
> DW_PCIE_RC_TYPE. This way, we will be able to add EP mode in a follow-up
> commit in a much less intrusive way, which makes the follup-up commit much
> easier to review.
> 
> No functional change intended.
> 
> Signed-off-by: Niklas Cassel <cassel@kernel.org>

Few nitpicks below. With those addressed,

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

> ---
>  drivers/pci/controller/dwc/pcie-dw-rockchip.c | 84 +++++++++++++++++++--------
>  1 file changed, 60 insertions(+), 24 deletions(-)
> 
> diff --git a/drivers/pci/controller/dwc/pcie-dw-rockchip.c b/drivers/pci/controller/dwc/pcie-dw-rockchip.c
> index 1380e3a5284b..e133511692af 100644
> --- a/drivers/pci/controller/dwc/pcie-dw-rockchip.c
> +++ b/drivers/pci/controller/dwc/pcie-dw-rockchip.c
> @@ -49,15 +49,20 @@
>  #define PCIE_LTSSM_STATUS_MASK		GENMASK(5, 0)
>  
>  struct rockchip_pcie {
> -	struct dw_pcie			pci;
> -	void __iomem			*apb_base;
> -	struct phy			*phy;
> -	struct clk_bulk_data		*clks;
> -	unsigned int			clk_cnt;
> -	struct reset_control		*rst;
> -	struct gpio_desc		*rst_gpio;
> -	struct regulator                *vpcie3v3;
> -	struct irq_domain		*irq_domain;
> +	struct dw_pcie				pci;
> +	void __iomem				*apb_base;
> +	struct phy				*phy;
> +	struct clk_bulk_data			*clks;
> +	unsigned int				clk_cnt;
> +	struct reset_control			*rst;
> +	struct gpio_desc			*rst_gpio;
> +	struct regulator			*vpcie3v3;
> +	struct irq_domain			*irq_domain;
> +	const struct rockchip_pcie_of_data	*data;

I prefer to avoid aligning the struct members just for this reason. Once you add
a member with a bigger name, then you need to align others also. Please just use
space.

> +};
> +
> +struct rockchip_pcie_of_data {
> +	enum dw_pcie_device_mode mode;
>  };
>  
>  static int rockchip_pcie_readl_apb(struct rockchip_pcie *rockchip, u32 reg)
> @@ -195,7 +200,6 @@ static int rockchip_pcie_host_init(struct dw_pcie_rp *pp)
>  	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
>  	struct rockchip_pcie *rockchip = to_rockchip_pcie(pci);
>  	struct device *dev = rockchip->pci.dev;
> -	u32 val = HIWORD_UPDATE_BIT(PCIE_LTSSM_ENABLE_ENHANCE);
>  	int irq, ret;
>  
>  	irq = of_irq_get_byname(dev->of_node, "legacy");
> @@ -209,12 +213,6 @@ static int rockchip_pcie_host_init(struct dw_pcie_rp *pp)
>  	irq_set_chained_handler_and_data(irq, rockchip_pcie_intx_handler,
>  					 rockchip);
>  
> -	/* LTSSM enable control mode */
> -	rockchip_pcie_writel_apb(rockchip, val, PCIE_CLIENT_HOT_RESET_CTRL);
> -
> -	rockchip_pcie_writel_apb(rockchip, PCIE_CLIENT_RC_MODE,
> -				 PCIE_CLIENT_GENERAL_CONTROL);
> -
>  	return 0;
>  }
>  
> @@ -294,13 +292,35 @@ static const struct dw_pcie_ops dw_pcie_ops = {
>  	.start_link = rockchip_pcie_start_link,
>  };
>  
> +static int rockchip_pcie_configure_rc(struct rockchip_pcie *rockchip)
> +{
> +	struct dw_pcie_rp *pp;
> +	u32 val;
> +
> +	/* LTSSM enable control mode */
> +	val = HIWORD_UPDATE_BIT(PCIE_LTSSM_ENABLE_ENHANCE);
> +	rockchip_pcie_writel_apb(rockchip, val, PCIE_CLIENT_HOT_RESET_CTRL);
> +
> +	rockchip_pcie_writel_apb(rockchip, PCIE_CLIENT_RC_MODE,
> +				 PCIE_CLIENT_GENERAL_CONTROL);
> +
> +	pp = &rockchip->pci.pp;
> +	pp->ops = &rockchip_pcie_host_ops;
> +
> +	return dw_pcie_host_init(pp);
> +}
> +
>  static int rockchip_pcie_probe(struct platform_device *pdev)
>  {
>  	struct device *dev = &pdev->dev;
>  	struct rockchip_pcie *rockchip;
> -	struct dw_pcie_rp *pp;
> +	const struct rockchip_pcie_of_data *data;
>  	int ret;
>  
> +	data = of_device_get_match_data(dev);
> +	if (!data)
> +		return -EINVAL;

-ENODATA?

> +
>  	rockchip = devm_kzalloc(dev, sizeof(*rockchip), GFP_KERNEL);
>  	if (!rockchip)
>  		return -ENOMEM;
> @@ -309,9 +329,7 @@ static int rockchip_pcie_probe(struct platform_device *pdev)
>  
>  	rockchip->pci.dev = dev;
>  	rockchip->pci.ops = &dw_pcie_ops;
> -
> -	pp = &rockchip->pci.pp;
> -	pp->ops = &rockchip_pcie_host_ops;
> +	rockchip->data = data;
>  
>  	ret = rockchip_pcie_resource_get(pdev, rockchip);
>  	if (ret)
> @@ -347,10 +365,21 @@ static int rockchip_pcie_probe(struct platform_device *pdev)
>  	if (ret)
>  		goto deinit_phy;
>  
> -	ret = dw_pcie_host_init(pp);
> -	if (!ret)
> -		return 0;

Thanks a lot for getting rid of this ugly piece of code!

- Mani

-- 
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