[PATCH v7 10/15] irqchip/riscv-imsic: Add support for PCI MSI irqdomain

From: Anup Patel
Date: Wed Aug 02 2023 - 11:02:50 EST


The Linux PCI framework requires it's own dedicated MSI irqdomain so
let us create PCI MSI irqdomain as child of the IMSIC base irqdomain.

Signed-off-by: Anup Patel <apatel@xxxxxxxxxxxxxxxx>
---
drivers/irqchip/Kconfig | 7 ++++
drivers/irqchip/irq-riscv-imsic-platform.c | 48 ++++++++++++++++++++++
drivers/irqchip/irq-riscv-imsic-state.h | 1 +
3 files changed, 56 insertions(+)

diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index 8ef18be5f37b..d700980372ef 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -550,6 +550,13 @@ config RISCV_IMSIC
select IRQ_DOMAIN_HIERARCHY
select GENERIC_MSI_IRQ

+config RISCV_IMSIC_PCI
+ bool
+ depends on RISCV_IMSIC
+ depends on PCI
+ depends on PCI_MSI
+ default RISCV_IMSIC
+
config EXYNOS_IRQ_COMBINER
bool "Samsung Exynos IRQ combiner support" if COMPILE_TEST
depends on (ARCH_EXYNOS && ARM) || COMPILE_TEST
diff --git a/drivers/irqchip/irq-riscv-imsic-platform.c b/drivers/irqchip/irq-riscv-imsic-platform.c
index b78f1b2ee3dc..ff737b4e195f 100644
--- a/drivers/irqchip/irq-riscv-imsic-platform.c
+++ b/drivers/irqchip/irq-riscv-imsic-platform.c
@@ -12,6 +12,7 @@
#include <linux/irqdomain.h>
#include <linux/module.h>
#include <linux/msi.h>
+#include <linux/pci.h>
#include <linux/platform_device.h>
#include <linux/spinlock.h>
#include <linux/smp.h>
@@ -184,6 +185,39 @@ static const struct irq_domain_ops imsic_base_domain_ops = {
.free = imsic_irq_domain_free,
};

+#ifdef CONFIG_RISCV_IMSIC_PCI
+
+static void imsic_pci_mask_irq(struct irq_data *d)
+{
+ pci_msi_mask_irq(d);
+ irq_chip_mask_parent(d);
+}
+
+static void imsic_pci_unmask_irq(struct irq_data *d)
+{
+ pci_msi_unmask_irq(d);
+ irq_chip_unmask_parent(d);
+}
+
+static struct irq_chip imsic_pci_irq_chip = {
+ .name = "IMSIC-PCI",
+ .irq_mask = imsic_pci_mask_irq,
+ .irq_unmask = imsic_pci_unmask_irq,
+ .irq_eoi = irq_chip_eoi_parent,
+};
+
+static struct msi_domain_ops imsic_pci_domain_ops = {
+};
+
+static struct msi_domain_info imsic_pci_domain_info = {
+ .flags = (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
+ MSI_FLAG_PCI_MSIX | MSI_FLAG_MULTI_PCI_MSI),
+ .ops = &imsic_pci_domain_ops,
+ .chip = &imsic_pci_irq_chip,
+};
+
+#endif
+
static struct irq_chip imsic_plat_irq_chip = {
.name = "IMSIC-PLAT",
};
@@ -208,12 +242,26 @@ static int imsic_irq_domains_init(struct device *dev)
}
irq_domain_update_bus_token(imsic->base_domain, DOMAIN_BUS_NEXUS);

+#ifdef CONFIG_RISCV_IMSIC_PCI
+ /* Create PCI MSI domain */
+ imsic->pci_domain = pci_msi_create_irq_domain(dev->fwnode,
+ &imsic_pci_domain_info,
+ imsic->base_domain);
+ if (!imsic->pci_domain) {
+ dev_err(dev, "failed to create IMSIC PCI domain\n");
+ irq_domain_remove(imsic->base_domain);
+ return -ENOMEM;
+ }
+#endif
+
/* Create Platform MSI domain */
imsic->plat_domain = platform_msi_create_irq_domain(dev->fwnode,
&imsic_plat_domain_info,
imsic->base_domain);
if (!imsic->plat_domain) {
dev_err(dev, "failed to create IMSIC platform domain\n");
+ if (imsic->pci_domain)
+ irq_domain_remove(imsic->pci_domain);
irq_domain_remove(imsic->base_domain);
return -ENOMEM;
}
diff --git a/drivers/irqchip/irq-riscv-imsic-state.h b/drivers/irqchip/irq-riscv-imsic-state.h
index 3170018949a8..ff3c377b9b33 100644
--- a/drivers/irqchip/irq-riscv-imsic-state.h
+++ b/drivers/irqchip/irq-riscv-imsic-state.h
@@ -31,6 +31,7 @@ struct imsic_priv {

/* IRQ domains (created by platform driver) */
struct irq_domain *base_domain;
+ struct irq_domain *pci_domain;
struct irq_domain *plat_domain;
};

--
2.34.1