[PATCH v15 15/23] PCI: microchip: Add event irqchip field to host port and add PLDA irqchip

[Minda Chen]

> 
> As PLDA dts binding doc(Documentation/devicetree/bindings/pci/
> plda,xpressrich3-axi-common.yaml) showed, PLDA PCIe contains an interrupt
> controller.
> 
> Microchip PolarFire PCIE event IRQs includes PLDA interrupts and Polarfire their
> own interrupts. The interrupt irqchip ops includes ack/mask/unmask interrupt
> ops, which will write correct registers.
> Microchip Polarfire PCIe additional interrupts require to write Polarfire SoC
> self-defined registers. So Microchip PCIe event irqchip ops can not be re-used.
> 
> To support PLDA its own event IRQ process, implements PLDA irqchip ops and
> add event irqchip field to struct pcie_plda_rp.
> 
> Signed-off-by: Minda Chen <minda.chen at starfivetech.com>
> Acked-by: Conor Dooley <conor.dooley at microchip.com>
> ---
>  .../pci/controller/plda/pcie-microchip-host.c | 66 ++++++++++++++++++-
>  drivers/pci/controller/plda/pcie-plda.h       |  3 +
>  2 files changed, 68 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/pci/controller/plda/pcie-microchip-host.c
> b/drivers/pci/controller/plda/pcie-microchip-host.c
> index b3df373a2141..beaf5c27da84 100644
> --- a/drivers/pci/controller/plda/pcie-microchip-host.c
> +++ b/drivers/pci/controller/plda/pcie-microchip-host.c
> @@ -770,6 +770,64 @@ static struct irq_chip mc_event_irq_chip = {
>  	.irq_unmask = mc_unmask_event_irq,
>  };
> 
Hi Thomas
  I think this patch code it is easy to review. If you busy, Could you let other
IRQ maintainer review? Thanks.

Hi Lorenzo, Bjorn and Krzysztof
  Now the code is pending several weeks. Maybe this patch is blocking.
Actually I write irqchip ops(ack/mask/unmask) like microchip irqchip ops. 
They looks very simple that write PLDA mask or status register. They all call the 
same function plda_hwirq_to_mask(). Now you can see this function below. 
Except INTx interrupt, one irqnum mapping to one register bit. The PLDA register
graph can be seen 14th patch, which can show all the PLDA interrupts and easy to
 get PLDA codes logic.

  Now the 6.9-next will be closed less than 20 days. I still hope the refactoring patches
(patch 1 - 16) can be accepted to 6.9. (Starfive and PLDA patches have to be delayed 
to 6.10 or later). I will try my best to achieve it because this series patches reviewed lasts 
a long period and Conor have reviewed all the refactoring patches.

I have no experience in refactoring code before this series patches. I try my best to do this.
Maybe I did something wrong in this. Please forgive me.

> +static u32 plda_hwirq_to_mask(int hwirq) {
> +	u32 mask;
> +
> +	/* hwirq 23 - 0 are the same with register */
> +	if (hwirq < EVENT_PM_MSI_INT_INTX)
> +		mask = BIT(hwirq);
> +	else if (hwirq == EVENT_PM_MSI_INT_INTX)
> +		mask = PM_MSI_INT_INTX_MASK;
> +	else
> +		mask = BIT(hwirq + PCI_NUM_INTX - 1);
> +
> +	return mask;
> +}
> +
> +static void plda_ack_event_irq(struct irq_data *data) {
> +	struct plda_pcie_rp *port = irq_data_get_irq_chip_data(data);
> +
> +	writel_relaxed(plda_hwirq_to_mask(data->hwirq),
> +		       port->bridge_addr + ISTATUS_LOCAL); }
> +
> +static void plda_mask_event_irq(struct irq_data *data) {
> +	struct plda_pcie_rp *port = irq_data_get_irq_chip_data(data);
> +	u32 mask, val;
> +
> +	mask = plda_hwirq_to_mask(data->hwirq);
> +
> +	raw_spin_lock(&port->lock);
> +	val = readl_relaxed(port->bridge_addr + IMASK_LOCAL);
> +	val &= ~mask;
> +	writel_relaxed(val, port->bridge_addr + IMASK_LOCAL);
> +	raw_spin_unlock(&port->lock);
> +}
> +
> +static void plda_unmask_event_irq(struct irq_data *data) {
> +	struct plda_pcie_rp *port = irq_data_get_irq_chip_data(data);
> +	u32 mask, val;
> +
> +	mask = plda_hwirq_to_mask(data->hwirq);
> +
> +	raw_spin_lock(&port->lock);
> +	val = readl_relaxed(port->bridge_addr + IMASK_LOCAL);
> +	val |= mask;
> +	writel_relaxed(val, port->bridge_addr + IMASK_LOCAL);
> +	raw_spin_unlock(&port->lock);
> +}
> +
> +static struct irq_chip plda_event_irq_chip = {
> +	.name = "PLDA PCIe EVENT",
> +	.irq_ack = plda_ack_event_irq,
> +	.irq_mask = plda_mask_event_irq,
> +	.irq_unmask = plda_unmask_event_irq,
> +};
> +
>  static const struct plda_event_ops plda_event_ops = {
>  	.get_events = plda_get_events,
>  };
> @@ -777,7 +835,9 @@ static const struct plda_event_ops plda_event_ops =
> {  static int plda_pcie_event_map(struct irq_domain *domain, unsigned int irq,
>  			       irq_hw_number_t hwirq)
>  {
> -	irq_set_chip_and_handler(irq, &mc_event_irq_chip, handle_level_irq);
> +	struct plda_pcie_rp *port = (void *)domain->host_data;
> +
> +	irq_set_chip_and_handler(irq, port->event_irq_chip, handle_level_irq);
>  	irq_set_chip_data(irq, domain->host_data);
> 
>  	return 0;
> @@ -962,6 +1022,9 @@ static int plda_init_interrupts(struct platform_device
> *pdev,
>  	if (!port->event_ops)
>  		port->event_ops = &plda_event_ops;
> 
> +	if (!port->event_irq_chip)
> +		port->event_irq_chip = &plda_event_irq_chip;
> +
>  	ret = plda_pcie_init_irq_domains(port);
>  	if (ret) {
>  		dev_err(dev, "failed creating IRQ domains\n"); @@ -1039,6 +1102,7
> @@ static int mc_platform_init(struct pci_config_window *cfg)
>  		return ret;
> 
>  	port->plda.event_ops = &mc_event_ops;
> +	port->plda.event_irq_chip = &mc_event_irq_chip;
> 
>  	/* Address translation is up; safe to enable interrupts */
>  	ret = plda_init_interrupts(pdev, &port->plda, &mc_event); diff --git
> a/drivers/pci/controller/plda/pcie-plda.h
> b/drivers/pci/controller/plda/pcie-plda.h
> index e0e5e7cc8434..a3ce01735bea 100644
> --- a/drivers/pci/controller/plda/pcie-plda.h
> +++ b/drivers/pci/controller/plda/pcie-plda.h
> @@ -107,6 +107,8 @@ enum plda_int_event {
> 
>  #define PLDA_NUM_DMA_EVENTS			16
> 
> +#define EVENT_PM_MSI_INT_INTX			(PLDA_NUM_DMA_EVENTS +
> PLDA_INTX)
> +#define EVENT_PM_MSI_INT_MSI			(PLDA_NUM_DMA_EVENTS +
> PLDA_MSI)
>  #define PLDA_MAX_EVENT_NUM			(PLDA_NUM_DMA_EVENTS +
> PLDA_INT_EVENT_NUM)
> 
>  /*
> @@ -155,6 +157,7 @@ struct plda_pcie_rp {
>  	raw_spinlock_t lock;
>  	struct plda_msi msi;
>  	const struct plda_event_ops *event_ops;
> +	const struct irq_chip *event_irq_chip;
>  	void __iomem *bridge_addr;
>  	int num_events;
>  };
> --
> 2.17.1