Re: [PATCH v4 3/9] PCI: keystone: Convert to using hierarchy domain for legacy interrupts
From: Lorenzo Pieralisi
Date: Thu Feb 21 2019 - 11:24:24 EST
On Thu, Feb 21, 2019 at 03:45:12PM +0530, Kishon Vijay Abraham I wrote:
> K2G provides separate IRQ lines for each of the four legacy interrupts.
> Model this using hierarchy domain instead of linear domain with chained
> IRQ handler.
>
> Signed-off-by: Kishon Vijay Abraham I <kishon@xxxxxx>
> ---
> drivers/pci/controller/dwc/pci-keystone.c | 205 +++++++++++++---------
> 1 file changed, 118 insertions(+), 87 deletions(-)
Hi Kishon,
I CC'ed Marc because you are actually re-writing an interrupt controller
driver so I would be happier to merge this refactoring if Marc can have
a look and he is satisfied with it - more so because most of the code can
be reused by other host bridge drivers with similar behaviour.
I will have a look too, unfortunately it is becoming a bit tight for
v5.1 but let's see how it goes.
Thanks,
Lorenzo
> diff --git a/drivers/pci/controller/dwc/pci-keystone.c b/drivers/pci/controller/dwc/pci-keystone.c
> index 47f0dcf638f2..7f1648453f54 100644
> --- a/drivers/pci/controller/dwc/pci-keystone.c
> +++ b/drivers/pci/controller/dwc/pci-keystone.c
> @@ -61,6 +61,7 @@
>
> #define IRQ_STATUS(n) (0x184 + ((n) << 4))
> #define IRQ_ENABLE_SET(n) (0x188 + ((n) << 4))
> +#define IRQ_ENABLE_CLR(n) (0x18C + ((n) << 4))
> #define INTx_EN BIT(0)
>
> #define ERR_IRQ_STATUS 0x1c4
> @@ -87,7 +88,6 @@ struct keystone_pcie {
> struct dw_pcie *pci;
> /* PCI Device ID */
> u32 device_id;
> - int legacy_host_irqs[PCI_NUM_INTX];
> struct device_node *legacy_intc_np;
>
> int msi_host_irqs[MAX_MSI_HOST_IRQS];
> @@ -96,7 +96,6 @@ struct keystone_pcie {
> struct phy **phy;
> struct device_link **link;
> struct device_node *msi_intc_np;
> - struct irq_domain *legacy_irq_domain;
> struct device_node *np;
>
> int error_irq;
> @@ -199,26 +198,6 @@ static int ks_pcie_msi_host_init(struct pcie_port *pp)
> return dw_pcie_allocate_domains(pp);
> }
>
> -static void ks_pcie_handle_legacy_irq(struct keystone_pcie *ks_pcie,
> - int offset)
> -{
> - struct dw_pcie *pci = ks_pcie->pci;
> - struct device *dev = pci->dev;
> - u32 pending;
> - int virq;
> -
> - pending = ks_pcie_app_readl(ks_pcie, IRQ_STATUS(offset));
> -
> - if (BIT(0) & pending) {
> - virq = irq_linear_revmap(ks_pcie->legacy_irq_domain, offset);
> - dev_dbg(dev, ": irq: irq_offset %d, virq %d\n", offset, virq);
> - generic_handle_irq(virq);
> - }
> -
> - /* EOI the INTx interrupt */
> - ks_pcie_app_writel(ks_pcie, IRQ_EOI, offset);
> -}
> -
> static void ks_pcie_enable_error_irq(struct keystone_pcie *ks_pcie)
> {
> ks_pcie_app_writel(ks_pcie, ERR_IRQ_ENABLE_SET, ERR_IRQ_ALL);
> @@ -256,39 +235,117 @@ static irqreturn_t ks_pcie_handle_error_irq(struct keystone_pcie *ks_pcie)
> return IRQ_HANDLED;
> }
>
> -static void ks_pcie_ack_legacy_irq(struct irq_data *d)
> +void ks_pcie_irq_eoi(struct irq_data *data)
> {
> + struct keystone_pcie *ks_pcie = irq_data_get_irq_chip_data(data);
> + irq_hw_number_t hwirq = data->hwirq;
> +
> + ks_pcie_app_writel(ks_pcie, IRQ_EOI, hwirq);
> + irq_chip_eoi_parent(data);
> }
>
> -static void ks_pcie_mask_legacy_irq(struct irq_data *d)
> +void ks_pcie_irq_enable(struct irq_data *data)
> {
> + struct keystone_pcie *ks_pcie = irq_data_get_irq_chip_data(data);
> + irq_hw_number_t hwirq = data->hwirq;
> +
> + ks_pcie_app_writel(ks_pcie, IRQ_ENABLE_SET(hwirq), INTx_EN);
> + irq_chip_enable_parent(data);
> }
>
> -static void ks_pcie_unmask_legacy_irq(struct irq_data *d)
> +void ks_pcie_irq_disable(struct irq_data *data)
> {
> + struct keystone_pcie *ks_pcie = irq_data_get_irq_chip_data(data);
> + irq_hw_number_t hwirq = data->hwirq;
> +
> + ks_pcie_app_writel(ks_pcie, IRQ_ENABLE_CLR(hwirq), INTx_EN);
> + irq_chip_disable_parent(data);
> }
>
> static struct irq_chip ks_pcie_legacy_irq_chip = {
> - .name = "Keystone-PCI-Legacy-IRQ",
> - .irq_ack = ks_pcie_ack_legacy_irq,
> - .irq_mask = ks_pcie_mask_legacy_irq,
> - .irq_unmask = ks_pcie_unmask_legacy_irq,
> + .name = "Keystone-PCI-Legacy-IRQ",
> + .irq_enable = ks_pcie_irq_enable,
> + .irq_disable = ks_pcie_irq_disable,
> + .irq_eoi = ks_pcie_irq_eoi,
> + .irq_mask = irq_chip_mask_parent,
> + .irq_unmask = irq_chip_unmask_parent,
> + .irq_retrigger = irq_chip_retrigger_hierarchy,
> + .irq_set_type = irq_chip_set_type_parent,
> + .irq_set_affinity = irq_chip_set_affinity_parent,
> };
>
> -static int ks_pcie_init_legacy_irq_map(struct irq_domain *d,
> - unsigned int irq,
> - irq_hw_number_t hw_irq)
> +static int ks_pcie_legacy_irq_domain_alloc(struct irq_domain *domain,
> + unsigned int virq,
> + unsigned int nr_irqs, void *data)
> {
> - irq_set_chip_and_handler(irq, &ks_pcie_legacy_irq_chip,
> - handle_level_irq);
> - irq_set_chip_data(irq, d->host_data);
> + struct keystone_pcie *ks_pcie = domain->host_data;
> + struct device_node *np = ks_pcie->legacy_intc_np;
> + struct irq_fwspec parent_fwspec, *fwspec = data;
> + struct of_phandle_args out_irq;
> + int ret, i;
> +
> + if (nr_irqs != 1)
> + return -EINVAL;
> +
> + ret = of_irq_parse_one(np, fwspec->param[0], &out_irq);
> + if (ret < 0) {
> + pr_err("Failed to parse interrupt node\n");
> + return ret;
> + }
> +
> + parent_fwspec.fwnode = &out_irq.np->fwnode;
> + parent_fwspec.param_count = out_irq.args_count;
> +
> + for (i = 0; i < out_irq.args_count; i++)
> + parent_fwspec.param[i] = out_irq.args[i];
> +
> + ret = irq_domain_alloc_irqs_parent(domain, virq, 1, &parent_fwspec);
> + if (ret < 0) {
> + pr_err("Failed to allocate parent irq %u: %d\n",
> + parent_fwspec.param[0], ret);
> + return ret;
> + }
> +
> + ret = irq_domain_set_hwirq_and_chip(domain, virq, fwspec->param[0],
> + &ks_pcie_legacy_irq_chip, ks_pcie);
> + if (ret < 0) {
> + pr_err("Failed to set hwirq and chip\n");
> + goto err_set_hwirq_and_chip;
> + }
>
> return 0;
> +
> +err_set_hwirq_and_chip:
> + irq_domain_free_irqs_parent(domain, virq, 1);
> +
> + return ret;
> +}
> +
> +static int ks_pcie_irq_domain_translate(struct irq_domain *domain,
> + struct irq_fwspec *fwspec,
> + unsigned long *hwirq,
> + unsigned int *type)
> +{
> + if (is_of_node(fwspec->fwnode)) {
> + if (fwspec->param_count != 2)
> + return -EINVAL;
> +
> + if (fwspec->param[0] >= PCI_NUM_INTX)
> + return -EINVAL;
> +
> + *hwirq = fwspec->param[0];
> + *type = fwspec->param[1];
> +
> + return 0;
> + }
> +
> + return -EINVAL;
> }
>
> static const struct irq_domain_ops ks_pcie_legacy_irq_domain_ops = {
> - .map = ks_pcie_init_legacy_irq_map,
> - .xlate = irq_domain_xlate_onetwocell,
> + .alloc = ks_pcie_legacy_irq_domain_alloc,
> + .free = irq_domain_free_irqs_common,
> + .translate = ks_pcie_irq_domain_translate,
> };
>
> /**
> @@ -572,35 +629,6 @@ static void ks_pcie_msi_irq_handler(struct irq_desc *desc)
> chained_irq_exit(chip, desc);
> }
>
> -/**
> - * ks_pcie_legacy_irq_handler() - Handle legacy interrupt
> - * @irq: IRQ line for legacy interrupts
> - * @desc: Pointer to irq descriptor
> - *
> - * Traverse through pending legacy interrupts and invoke handler for each. Also
> - * takes care of interrupt controller level mask/ack operation.
> - */
> -static void ks_pcie_legacy_irq_handler(struct irq_desc *desc)
> -{
> - unsigned int irq = irq_desc_get_irq(desc);
> - struct keystone_pcie *ks_pcie = irq_desc_get_handler_data(desc);
> - struct dw_pcie *pci = ks_pcie->pci;
> - struct device *dev = pci->dev;
> - u32 irq_offset = irq - ks_pcie->legacy_host_irqs[0];
> - struct irq_chip *chip = irq_desc_get_chip(desc);
> -
> - dev_dbg(dev, ": Handling legacy irq %d\n", irq);
> -
> - /*
> - * The chained irq handler installation would have replaced normal
> - * interrupt driver handler so we need to take care of mask/unmask and
> - * ack operation.
> - */
> - chained_irq_enter(chip, desc);
> - ks_pcie_handle_legacy_irq(ks_pcie, irq_offset);
> - chained_irq_exit(chip, desc);
> -}
> -
> static int ks_pcie_config_msi_irq(struct keystone_pcie *ks_pcie)
> {
> struct device *dev = ks_pcie->pci->dev;
> @@ -655,14 +683,33 @@ static int ks_pcie_config_legacy_irq(struct keystone_pcie *ks_pcie)
> struct device *dev = ks_pcie->pci->dev;
> struct irq_domain *legacy_irq_domain;
> struct device_node *np = ks_pcie->np;
> + struct irq_domain *parent_domain;
> + struct device_node *parent_node;
> struct device_node *intc_np;
> - int irq_count, irq, ret = 0, i;
> + int irq_count, ret = 0;
>
> intc_np = of_get_child_by_name(np, "legacy-interrupt-controller");
> if (!intc_np) {
> dev_warn(dev, "legacy-interrupt-controller node is absent\n");
> return -EINVAL;
> }
> + ks_pcie->legacy_intc_np = intc_np;
> +
> + parent_node = of_irq_find_parent(intc_np);
> + if (!parent_node) {
> + dev_err(dev, "unable to obtain parent node\n");
> + ret = -ENXIO;
> + goto err;
> + }
> +
> + parent_domain = irq_find_host(parent_node);
> + if (!parent_domain) {
> + dev_err(dev, "unable to obtain parent domain\n");
> + ret = -ENXIO;
> + goto err;
> + }
> +
> + of_node_put(parent_node);
>
> irq_count = of_irq_count(intc_np);
> if (!irq_count) {
> @@ -671,31 +718,15 @@ static int ks_pcie_config_legacy_irq(struct keystone_pcie *ks_pcie)
> goto err;
> }
>
> - for (i = 0; i < irq_count; i++) {
> - irq = irq_of_parse_and_map(intc_np, i);
> - if (!irq) {
> - ret = -EINVAL;
> - goto err;
> - }
> - ks_pcie->legacy_host_irqs[i] = irq;
> -
> - irq_set_chained_handler_and_data(irq,
> - ks_pcie_legacy_irq_handler,
> - ks_pcie);
> - }
> -
> legacy_irq_domain =
> - irq_domain_add_linear(intc_np, PCI_NUM_INTX,
> - &ks_pcie_legacy_irq_domain_ops, NULL);
> + irq_domain_add_hierarchy(parent_domain, 0, PCI_NUM_INTX,
> + intc_np,
> + &ks_pcie_legacy_irq_domain_ops,
> + ks_pcie);
> if (!legacy_irq_domain) {
> dev_err(dev, "Failed to add irq domain for legacy irqs\n");
> ret = -EINVAL;
> - goto err;
> }
> - ks_pcie->legacy_irq_domain = legacy_irq_domain;
> -
> - for (i = 0; i < PCI_NUM_INTX; i++)
> - ks_pcie_app_writel(ks_pcie, IRQ_ENABLE_SET(i), INTx_EN);
>
> err:
> of_node_put(intc_np);
> --
> 2.17.1
>