Probe for the 'msi-ranges' property, and implement the MSI
support in the form of the usual two-level hierarchy.
Note that contrary to the wired interrupts, MSIs are shared among
all the ports.
Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx>
---
drivers/pci/controller/pcie-apple.c | 168 +++++++++++++++++++++++++++-
1 file changed, 167 insertions(+), 1 deletion(-)
diff --git a/drivers/pci/controller/pcie-apple.c b/drivers/pci/controller/pcie-apple.c
index d174a215a47d..1ed7b90f8360 100644
--- a/drivers/pci/controller/pcie-apple.c
+++ b/drivers/pci/controller/pcie-apple.c
@@ -116,10 +116,22 @@
#define PORT_TUNSTAT_PERST_ACK_PEND BIT(1)
#define PORT_PREFMEM_ENABLE 0x00994
+/*
+ * The doorbell address is set to 0xfffff000, which by convention
+ * matches what MacOS does, and it is possible to use any other
+ * address (in the bottom 4GB, as the base register is only 32bit).
+ */
+#define DOORBELL_ADDR 0xfffff000
+
struct apple_pcie {
+ struct mutex lock;
struct device *dev;
void __iomem *base;
+ struct irq_domain *domain;
+ unsigned long *bitmap;
struct completion event;
+ struct irq_fwspec fwspec;
+ u32 nvecs;
};
struct apple_pcie_port {
@@ -135,6 +147,103 @@ static inline void rmwl(u32 clr, u32 set, void __iomem *addr)
writel_relaxed((readl_relaxed(addr) & ~clr) | set, addr);
}
+static void apple_msi_top_irq_mask(struct irq_data *d)
+{
+ pci_msi_mask_irq(d);
+ irq_chip_mask_parent(d);
+}
+
+static void apple_msi_top_irq_unmask(struct irq_data *d)
+{
+ pci_msi_unmask_irq(d);
+ irq_chip_unmask_parent(d);
+}
+
+static struct irq_chip apple_msi_top_chip = {
+ .name = "PCIe MSI",
+ .irq_mask = apple_msi_top_irq_mask,
+ .irq_unmask = apple_msi_top_irq_unmask,
+ .irq_eoi = irq_chip_eoi_parent,
+ .irq_set_affinity = irq_chip_set_affinity_parent,
+ .irq_set_type = irq_chip_set_type_parent,
+};
+
+static void apple_msi_compose_msg(struct irq_data *data, struct msi_msg *msg)
+{
+ BUILD_BUG_ON(upper_32_bits(DOORBELL_ADDR));
+
+ msg->address_hi = upper_32_bits(DOORBELL_ADDR);
+ msg->address_lo = lower_32_bits(DOORBELL_ADDR);
+ msg->data = data->hwirq;
+}
+
+static struct irq_chip apple_msi_bottom_chip = {
+ .name = "MSI",
+ .irq_mask = irq_chip_mask_parent,
+ .irq_unmask = irq_chip_unmask_parent,
+ .irq_eoi = irq_chip_eoi_parent,
+ .irq_set_affinity = irq_chip_set_affinity_parent,
+ .irq_set_type = irq_chip_set_type_parent,
+ .irq_compose_msi_msg = apple_msi_compose_msg,
+};
+
+static int apple_msi_domain_alloc(struct irq_domain *domain, unsigned int virq,
+ unsigned int nr_irqs, void *args)
+{
+ struct apple_pcie *pcie = domain->host_data;
+ struct irq_fwspec fwspec = pcie->fwspec;
+ unsigned int i;
+ int ret, hwirq;
+
+ mutex_lock(&pcie->lock);
+
+ hwirq = bitmap_find_free_region(pcie->bitmap, pcie->nvecs,
+ order_base_2(nr_irqs));
+
+ mutex_unlock(&pcie->lock);
+
+ if (hwirq < 0)
+ return -ENOSPC;
+
+ fwspec.param[1] += hwirq;
+
+ ret = irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, &fwspec);
+ if (ret)
+ return ret;
+
+ for (i = 0; i < nr_irqs; i++) {
+ irq_domain_set_hwirq_and_chip(domain, virq + i, hwirq + i,
+ &apple_msi_bottom_chip,
+ domain->host_data);
+ }
+
+ return 0;
+}
+
+static void apple_msi_domain_free(struct irq_domain *domain, unsigned int virq,
+ unsigned int nr_irqs)
+{
+ struct irq_data *d = irq_domain_get_irq_data(domain, virq);
+ struct apple_pcie *pcie = domain->host_data;
+
+ mutex_lock(&pcie->lock);
+
+ bitmap_release_region(pcie->bitmap, d->hwirq, order_base_2(nr_irqs));
+
+ mutex_unlock(&pcie->lock);
+}
+
+static const struct irq_domain_ops apple_msi_domain_ops = {
+ .alloc = apple_msi_domain_alloc,
+ .free = apple_msi_domain_free,
+};
+
+static struct msi_domain_info apple_msi_info = {
+ .flags = (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
+ MSI_FLAG_MULTI_PCI_MSI | MSI_FLAG_PCI_MSIX),
+ .chip = &apple_msi_top_chip,
+};
+
static void apple_port_irq_mask(struct irq_data *data)
{
struct apple_pcie_port *port = irq_data_get_irq_chip_data(data);
@@ -269,6 +378,14 @@ static int apple_pcie_port_setup_irq(struct apple_pcie_port *port)
irq_set_chained_handler_and_data(irq, apple_port_irq_handler, port);
+ /* Configure MSI base address */
+ writel_relaxed(lower_32_bits(DOORBELL_ADDR), port->base + PORT_MSIADDR);
+
+ /* Enable MSIs, shared between all ports */
+ writel_relaxed(0, port->base + PORT_MSIBASE);
+ writel_relaxed((ilog2(port->pcie->nvecs) << PORT_MSICFG_L2MSINUM_SHIFT) |
+ PORT_MSICFG_EN, port->base + PORT_MSICFG);
+
return 0;
}
@@ -436,6 +553,55 @@ static int apple_pcie_setup_port(struct apple_pcie *pcie,
return 0;
}
+static int apple_msi_init(struct apple_pcie *pcie)
+{
+ struct fwnode_handle *fwnode = dev_fwnode(pcie->dev);
+ struct of_phandle_args args = {};
+ struct irq_domain *parent;
+ int ret;
+
+ ret = of_parse_phandle_with_args(to_of_node(fwnode), "msi-ranges",
+ "#interrupt-cells", 0, &args);
+ if (ret)
+ return ret;
+
+ ret = of_property_read_u32_index(to_of_node(fwnode), "msi-ranges",
+ args.args_count + 1, &pcie->nvecs);
+ if (ret)
+ return ret;
+
+ of_phandle_args_to_fwspec(args.np, args.args, args.args_count,
+ &pcie->fwspec);
+
+ pcie->bitmap = devm_bitmap_zalloc(pcie->dev, pcie->nvecs, GFP_KERNEL);
+ if (!pcie->bitmap)
+ return -ENOMEM;
+
+ parent = irq_find_matching_fwspec(&pcie->fwspec, DOMAIN_BUS_WIRED);
+ if (!parent) {
+ dev_err(pcie->dev, "failed to find parent domain\n");
+ return -ENXIO;
+ }
+
+ parent = irq_domain_create_hierarchy(parent, 0, pcie->nvecs, fwnode,
+ &apple_msi_domain_ops, pcie);
+ if (!parent) {
+ dev_err(pcie->dev, "failed to create IRQ domain\n");
+ return -ENOMEM;
+ }
+ irq_domain_update_bus_token(parent, DOMAIN_BUS_NEXUS);
+
+ pcie->domain = pci_msi_create_irq_domain(fwnode, &apple_msi_info,
+ parent);
+ if (!pcie->domain) {
+ dev_err(pcie->dev, "failed to create MSI domain\n");
+ irq_domain_remove(parent);
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
static int apple_pcie_init(struct pci_config_window *cfg)
{
struct device *dev = cfg->parent;
@@ -465,7 +631,7 @@ static int apple_pcie_init(struct pci_config_window *cfg)
}
}
- return 0;
+ return apple_msi_init(pcie);
}
static const struct pci_ecam_ops apple_pcie_cfg_ecam_ops = {
--
2.30.2
