Re: [PATCH 06/11] PCI: rcar-gen4: Add Root Port reset support

[Marek Vasut <marek.vasut@mailbox.org>]

On 9/18/26 5:20 AM, Koichiro Den wrote:

[...]

> +++ b/drivers/pci/controller/dwc/pcie-rcar-gen4.c

[...]

> @@ -90,12 +91,22 @@ struct rcar_gen4_pcie_drvdata {
>   	enum dw_pcie_device_mode mode;
>   };
>   
> +enum rcar_gen4_pcie_state {
> +	/* The controller is being reset and reinitialized */
> +	RCAR_PCIE_RESETTING,
> +};
> +
>   struct rcar_gen4_pcie {
>   	struct dw_pcie dw;
>   	void __iomem *base;
>   	void __iomem *phy_base;
>   	struct platform_device *pdev;
>   	const struct rcar_gen4_pcie_drvdata *drvdata;
> +	unsigned long state;

Can we simply use boolean flags here in struct rcar_gen4_pcie, instead 
of the enum rcar_gen4_pcie_state ?

> +	/* Protects APP interrupt enable registers and their software state. */
> +	raw_spinlock_t app_lock;
> +	/* Serializes Root Port hardware reinitialization. */
> +	struct mutex reset_lock;
>   };
>   #define to_rcar_gen4_pcie(_dw)	container_of(_dw, struct rcar_gen4_pcie, dw)
>   
> @@ -344,6 +355,33 @@ static int rcar_gen4_pcie_host_msi_addr(struct dw_pcie_rp *pp, u32 *msi_addr)
>   	return 0;
>   }
>   
> +/* Whether the APP interrupt sources may currently be enabled. */
> +static bool rcar_gen4_pcie_irqs_blocked(struct rcar_gen4_pcie *rcar)
> +{
> +	return !!rcar->state;
> +}
> +
> +static void rcar_gen4_pcie_app_irq_sync_locked(struct rcar_gen4_pcie *rcar)
> +{
> +	bool armed = !rcar_gen4_pcie_irqs_blocked(rcar);
> +	u32 val;
> +
> +	lockdep_assert_held(&rcar->app_lock);
> +
> +	val = readl(rcar->base + PCIEINTSTS0EN);
> +	val &= ~MSI_CTRL_INT;
> +	if (armed && pci_msi_enabled())
> +		val |= MSI_CTRL_INT;

Should this function cache the state of pci_msi_enabled() in struct 
rcar_gen4_pcie , so that in case rcar_gen4_pcie_irqs_blocked() reports 
MSIs as blocked at this point ...

> +	writel(val, rcar->base + PCIEINTSTS0EN);
> +}
> +
> +static void rcar_gen4_pcie_app_irq_sync(struct rcar_gen4_pcie *rcar)
> +{
> +	guard(raw_spinlock_irqsave)(&rcar->app_lock);
> +
> +	rcar_gen4_pcie_app_irq_sync_locked(rcar);

... this function can enable MSIs once it is called and MSIs are no 
longer blocked ?

> +}
> +
>   static int rcar_gen4_pcie_host_msi_init(struct dw_pcie_rp *pp)
>   {
>   	struct dw_pcie *dw = to_dw_pcie_from_pp(pp);

[...]

-- 
Best regards,
Marek Vasut