Re: [PATCH v13 14/21] PCI: microchip: Add get_events() callback and add PLDA get_event()

Lorenzo Pieralisi
2023-12-27T16:32:06Z

On Thu, Dec 14, 2023 at 03:28:32PM +0800, Minda Chen wrote:
> PolarFire implements its own PCIe interrupts, additional to the regular
> PCIe interrupts, due to lack of an MSI controller, so the interrupt to
> event number mapping is different to the PLDA local interrupts,

I am sorry I don't understand what you mean here.

"its own PCIe interrupts" ?

"regular PCIe interrupts" ?

"PLDA local interrupts" ?

Can you spell out what those are referring to please ?

Thanks,
Lorenzo

> necessitating a custom get_events() implementation.
>
> plda_get_events() adds interrupt register to PLDA local event num mapping
> codes except DMA engine interrupt events. The DMA engine interrupt events
> are implemented by vendors.
>
> Signed-off-by: Minda Chen <minda.chen@starfivetech.com>
> Acked-by: Conor Dooley <conor.dooley@microchip.com>
> ---
> .../pci/controller/plda/pcie-microchip-host.c | 35 ++++++++++++++++++-
> drivers/pci/controller/plda/pcie-plda.h | 33 +++++++++++++++++
> 2 files changed, 67 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/pci/controller/plda/pcie-microchip-host.c b/drivers/pci/controller/plda/pcie-microchip-host.c
> index 00250781b11c..fd0d92c3d03f 100644
> --- a/drivers/pci/controller/plda/pcie-microchip-host.c
> +++ b/drivers/pci/controller/plda/pcie-microchip-host.c
> @@ -627,6 +627,26 @@ static u32 mc_get_events(struct plda_pcie_rp *port)
> return events;
> }
>
> +static u32 plda_get_events(struct plda_pcie_rp *port)
> +{
> + u32 events, val, origin;
> +
> + origin = readl_relaxed(port->bridge_addr + ISTATUS_LOCAL);
> +
> + /* Error events and doorbell events */
> + events = (origin & ERROR_AND_DOORBELL_MASK) >> A_ATR_EVT_POST_ERR_SHIFT;
> +
> + /* INTx events */
> + if (origin & PM_MSI_INT_INTX_MASK)
> + events |= BIT(EVENT_PM_MSI_INT_INTX);
> +
> + /* MSI event and sys events */
> + val = (origin & SYS_AND_MSI_MASK) >> PM_MSI_INT_MSI_SHIFT;
> + events |= val << EVENT_PM_MSI_INT_MSI;
> +
> + return events;
> +}
> +
> static irqreturn_t mc_event_handler(int irq, void *dev_id)
> {
> struct plda_pcie_rp *port = dev_id;
> @@ -657,7 +677,7 @@ static void plda_handle_event(struct irq_desc *desc)
>
> chained_irq_enter(chip, desc);
>
> - events = mc_get_events(port);
> + events = port->event_ops->get_events(port);
>
> for_each_set_bit(bit, &events, port->num_events)
> generic_handle_domain_irq(port->event_domain, bit);
> @@ -751,6 +771,10 @@ static struct irq_chip mc_event_irq_chip = {
> .irq_unmask = mc_unmask_event_irq,
> };
>
> +static const struct plda_event_ops plda_event_ops = {
> + .get_events = plda_get_events,
> +};
> +
> static int plda_pcie_event_map(struct irq_domain *domain, unsigned int irq,
> irq_hw_number_t hwirq)
> {
> @@ -816,6 +840,10 @@ static int mc_request_event_irq(struct plda_pcie_rp *plda, int event_irq,
> 0, event_cause[event].sym, plda);
> }
>
> +static const struct plda_event_ops mc_event_ops = {
> + .get_events = mc_get_events,
> +};
> +
> static const struct plda_event mc_event = {
> .request_event_irq = mc_request_event_irq,
> .intx_event = EVENT_LOCAL_PM_MSI_INT_INTX,
> @@ -932,6 +960,9 @@ static int plda_init_interrupts(struct platform_device *pdev,
> int i, intx_irq, msi_irq, event_irq;
> int ret;
>
> + if (!port->event_ops)
> + port->event_ops = &plda_event_ops;
> +
> ret = plda_pcie_init_irq_domains(port);
> if (ret) {
> dev_err(dev, "failed creating IRQ domains\n");
> @@ -1008,6 +1039,8 @@ static int mc_platform_init(struct pci_config_window *cfg)
> if (ret)
> return ret;
>
> + port->plda.event_ops = &mc_event_ops;
> +
> /* Address translation is up; safe to enable interrupts */
> ret = plda_init_interrupts(pdev, &port->plda, &mc_event);
> if (ret)
> diff --git a/drivers/pci/controller/plda/pcie-plda.h b/drivers/pci/controller/plda/pcie-plda.h
> index fba7343f9a96..dd8bc2750bfc 100644
> --- a/drivers/pci/controller/plda/pcie-plda.h
> +++ b/drivers/pci/controller/plda/pcie-plda.h
> @@ -40,6 +40,7 @@
> #define P_ATR_EVT_DISCARD_ERR_SHIFT 22
> #define P_ATR_EVT_DOORBELL_MASK 0x00000000u
> #define P_ATR_EVT_DOORBELL_SHIFT 23
> +#define ERROR_AND_DOORBELL_MASK GENMASK(23, 16)
> #define PM_MSI_INT_INTA_MASK 0x01000000u
> #define PM_MSI_INT_INTA_SHIFT 24
> #define PM_MSI_INT_INTB_MASK 0x02000000u
> @@ -58,6 +59,7 @@
> #define PM_MSI_INT_EVENTS_SHIFT 30
> #define PM_MSI_INT_SYS_ERR_MASK 0x80000000u
> #define PM_MSI_INT_SYS_ERR_SHIFT 31
> +#define SYS_AND_MSI_MASK GENMASK(31, 28)
> #define NUM_LOCAL_EVENTS 15
> #define ISTATUS_LOCAL 0x184
> #define IMASK_HOST 0x188
> @@ -102,6 +104,36 @@
> #define EVENT_PM_MSI_INT_SYS_ERR 12
> #define NUM_PLDA_EVENTS 13
>
> +/*
> + * PLDA local interrupt register
> + *
> + * 31 27 23 15 7 0
> + * +--+--+--+-+------+-+-+-+-+-+-+-+-+-----------+-----------+
> + * |12|11|10|9| intx |7|6|5|4|3|2|1|0| DMA error | DMA end |
> + * +--+--+--+-+------+-+-+-+-+-+-+-+-+-----------+-----------+
> + * 0: AXI post error
> + * 1: AXI fetch error
> + * 2: AXI discard error
> + * 3: AXI doorbell
> + * 4: PCIe post error
> + * 5: PCIe fetch error
> + * 6: PCIe discard error
> + * 7: PCIe doorbell
> + * 8: 4 INTx interruts
> + * 9: MSI interrupt
> + * 10: AER event
> + * 11: PM/LTR/Hotplug
> + * 12: System error
> + * DMA error : reserved for vendor implement
> + * DMA end : reserved for vendor implement
> + */
> +
> +struct plda_pcie_rp;
> +
> +struct plda_event_ops {
> + u32 (*get_events)(struct plda_pcie_rp *pcie);
> +};
> +
> struct plda_msi {
> struct mutex lock; /* Protect used bitmap */
> struct irq_domain *msi_domain;
> @@ -117,6 +149,7 @@ struct plda_pcie_rp {
> struct irq_domain *event_domain;
> raw_spinlock_t lock;
> struct plda_msi msi;
> + const struct plda_event_ops *event_ops;
> void __iomem *bridge_addr;
> int num_events;
> };
> --
> 2.17.1
>