diff options
| -rw-r--r-- | drivers/irqchip/Kconfig | 10 | ||||
| -rw-r--r-- | drivers/irqchip/Makefile | 1 | ||||
| -rw-r--r-- | drivers/irqchip/irq-loongson-pch-msi.c | 255 |
3 files changed, 266 insertions, 0 deletions
diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig index 5524a621638c..0b6b826dd843 100644 --- a/drivers/irqchip/Kconfig +++ b/drivers/irqchip/Kconfig @@ -549,4 +549,14 @@ config LOONGSON_PCH_PIC help Support for the Loongson PCH PIC Controller. +config LOONGSON_PCH_MSI + bool "Loongson PCH PIC Controller" + depends on MACH_LOONGSON64 || COMPILE_TEST + depends on PCI + default MACH_LOONGSON64 + select IRQ_DOMAIN_HIERARCHY + select PCI_MSI + help + Support for the Loongson PCH MSI Controller. + endmenu diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile index acc72331cec8..3a4ce283189a 100644 --- a/drivers/irqchip/Makefile +++ b/drivers/irqchip/Makefile @@ -109,3 +109,4 @@ obj-$(CONFIG_LOONGSON_LIOINTC) += irq-loongson-liointc.o obj-$(CONFIG_LOONGSON_HTPIC) += irq-loongson-htpic.o obj-$(CONFIG_LOONGSON_HTVEC) += irq-loongson-htvec.o obj-$(CONFIG_LOONGSON_PCH_PIC) += irq-loongson-pch-pic.o +obj-$(CONFIG_LOONGSON_PCH_MSI) += irq-loongson-pch-msi.o diff --git a/drivers/irqchip/irq-loongson-pch-msi.c b/drivers/irqchip/irq-loongson-pch-msi.c new file mode 100644 index 000000000000..50becd21008c --- /dev/null +++ b/drivers/irqchip/irq-loongson-pch-msi.c @@ -0,0 +1,255 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2020, Jiaxun Yang <jiaxun.yang@flygoat.com> + * Loongson PCH MSI support + */ + +#define pr_fmt(fmt) "pch-msi: " fmt + +#include <linux/irqchip.h> +#include <linux/msi.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <linux/of_pci.h> +#include <linux/pci.h> +#include <linux/slab.h> + +struct pch_msi_data { + struct mutex msi_map_lock; + phys_addr_t doorbell; + u32 irq_first; /* The vector number that MSIs starts */ + u32 num_irqs; /* The number of vectors for MSIs */ + unsigned long *msi_map; +}; + +static void pch_msi_mask_msi_irq(struct irq_data *d) +{ + pci_msi_mask_irq(d); + irq_chip_mask_parent(d); +} + +static void pch_msi_unmask_msi_irq(struct irq_data *d) +{ + irq_chip_unmask_parent(d); + pci_msi_unmask_irq(d); +} + +static struct irq_chip pch_msi_irq_chip = { + .name = "PCH PCI MSI", + .irq_mask = pch_msi_mask_msi_irq, + .irq_unmask = pch_msi_unmask_msi_irq, + .irq_ack = irq_chip_ack_parent, + .irq_set_affinity = irq_chip_set_affinity_parent, +}; + +static int pch_msi_allocate_hwirq(struct pch_msi_data *priv, int num_req) +{ + int first; + + mutex_lock(&priv->msi_map_lock); + + first = bitmap_find_free_region(priv->msi_map, priv->num_irqs, + get_count_order(num_req)); + if (first < 0) { + mutex_unlock(&priv->msi_map_lock); + return -ENOSPC; + } + + mutex_unlock(&priv->msi_map_lock); + + return priv->irq_first + first; +} + +static void pch_msi_free_hwirq(struct pch_msi_data *priv, + int hwirq, int num_req) +{ + int first = hwirq - priv->irq_first; + + mutex_lock(&priv->msi_map_lock); + bitmap_release_region(priv->msi_map, first, get_count_order(num_req)); + mutex_unlock(&priv->msi_map_lock); +} + +static void pch_msi_compose_msi_msg(struct irq_data *data, + struct msi_msg *msg) +{ + struct pch_msi_data *priv = irq_data_get_irq_chip_data(data); + + msg->address_hi = upper_32_bits(priv->doorbell); + msg->address_lo = lower_32_bits(priv->doorbell); + msg->data = data->hwirq; +} + +static struct msi_domain_info pch_msi_domain_info = { + .flags = MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS | + MSI_FLAG_MULTI_PCI_MSI | MSI_FLAG_PCI_MSIX, + .chip = &pch_msi_irq_chip, +}; + +static struct irq_chip middle_irq_chip = { + .name = "PCH MSI", + .irq_mask = irq_chip_mask_parent, + .irq_unmask = irq_chip_unmask_parent, + .irq_ack = irq_chip_ack_parent, + .irq_set_affinity = irq_chip_set_affinity_parent, + .irq_compose_msi_msg = pch_msi_compose_msi_msg, +}; + +static int pch_msi_parent_domain_alloc(struct irq_domain *domain, + unsigned int virq, int hwirq) +{ + struct irq_fwspec fwspec; + int ret; + + fwspec.fwnode = domain->parent->fwnode; + fwspec.param_count = 1; + fwspec.param[0] = hwirq; + + ret = irq_domain_alloc_irqs_parent(domain, virq, 1, &fwspec); + if (ret) + return ret; + + return 0; +} + +static int pch_msi_middle_domain_alloc(struct irq_domain *domain, + unsigned int virq, + unsigned int nr_irqs, void *args) +{ + struct pch_msi_data *priv = domain->host_data; + int hwirq, err, i; + + hwirq = pch_msi_allocate_hwirq(priv, nr_irqs); + if (hwirq < 0) + return hwirq; + + for (i = 0; i < nr_irqs; i++) { + err = pch_msi_parent_domain_alloc(domain, virq + i, hwirq + i); + if (err) + goto err_hwirq; + + irq_domain_set_hwirq_and_chip(domain, virq + i, hwirq + i, + &middle_irq_chip, priv); + } + + return 0; + +err_hwirq: + pch_msi_free_hwirq(priv, hwirq, nr_irqs); + irq_domain_free_irqs_parent(domain, virq, i - 1); + + return err; +} + +static void pch_msi_middle_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 pch_msi_data *priv = irq_data_get_irq_chip_data(d); + + irq_domain_free_irqs_parent(domain, virq, nr_irqs); + pch_msi_free_hwirq(priv, d->hwirq, nr_irqs); +} + +static const struct irq_domain_ops pch_msi_middle_domain_ops = { + .alloc = pch_msi_middle_domain_alloc, + .free = pch_msi_middle_domain_free, +}; + +static int pch_msi_init_domains(struct pch_msi_data *priv, + struct device_node *node, + struct irq_domain *parent) +{ + struct irq_domain *middle_domain, *msi_domain; + + middle_domain = irq_domain_create_linear(of_node_to_fwnode(node), + priv->num_irqs, + &pch_msi_middle_domain_ops, + priv); + if (!middle_domain) { + pr_err("Failed to create the MSI middle domain\n"); + return -ENOMEM; + } + + middle_domain->parent = parent; + irq_domain_update_bus_token(middle_domain, DOMAIN_BUS_NEXUS); + + msi_domain = pci_msi_create_irq_domain(of_node_to_fwnode(node), + &pch_msi_domain_info, + middle_domain); + if (!msi_domain) { + pr_err("Failed to create PCI MSI domain\n"); + irq_domain_remove(middle_domain); + return -ENOMEM; + } + + return 0; +} + +static int pch_msi_init(struct device_node *node, + struct device_node *parent) +{ + struct pch_msi_data *priv; + struct irq_domain *parent_domain; + struct resource res; + int ret; + + parent_domain = irq_find_host(parent); + if (!parent_domain) { + pr_err("Failed to find the parent domain\n"); + return -ENXIO; + } + + priv = kzalloc(sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + mutex_init(&priv->msi_map_lock); + + ret = of_address_to_resource(node, 0, &res); + if (ret) { + pr_err("Failed to allocate resource\n"); + goto err_priv; + } + + priv->doorbell = res.start; + + if (of_property_read_u32(node, "loongson,msi-base-vec", + &priv->irq_first)) { + pr_err("Unable to parse MSI vec base\n"); + ret = -EINVAL; + goto err_priv; + } + + if (of_property_read_u32(node, "loongson,msi-num-vecs", + &priv->num_irqs)) { + pr_err("Unable to parse MSI vec number\n"); + ret = -EINVAL; + goto err_priv; + } + + priv->msi_map = bitmap_alloc(priv->num_irqs, GFP_KERNEL); + if (!priv->msi_map) { + ret = -ENOMEM; + goto err_priv; + } + + pr_debug("Registering %d MSIs, starting at %d\n", + priv->num_irqs, priv->irq_first); + + ret = pch_msi_init_domains(priv, node, parent_domain); + if (ret) + goto err_map; + + return 0; + +err_map: + kfree(priv->msi_map); +err_priv: + kfree(priv); + return ret; +} + +IRQCHIP_DECLARE(pch_msi, "loongson,pch-msi-1.0", pch_msi_init); |