From 853a33ce6932601030f550653aea91a0e0a71511 Mon Sep 17 00:00:00 2001 From: Suravee Suthikulpanit Date: Tue, 25 Nov 2014 18:47:22 +0000 Subject: [PATCH] irqchip: gic-v2m: Add support for ARM GICv2m MSI(-X) doorbell ARM GICv2m specification extends GICv2 to support MSI(-X) with a new register frame. This allows a GICv2 based system to support MSI with minimal changes. Signed-off-by: Suravee Suthikulpanit [maz: converted the driver to use stacked irq domains, updated changelog] Signed-off-by: Marc Zyngier Link: https://lkml.kernel.org/r/1416941243-7181-2-git-send-email-marc.zyngier@arm.com Signed-off-by: Jason Cooper --- arch/arm64/Kconfig | 1 + drivers/irqchip/Kconfig | 6 + drivers/irqchip/Makefile | 1 + drivers/irqchip/irq-gic-v2m.c | 333 ++++++++++++++++++++++++++++++++ drivers/irqchip/irq-gic.c | 4 + include/linux/irqchip/arm-gic.h | 2 + 6 files changed, 347 insertions(+) create mode 100644 drivers/irqchip/irq-gic-v2m.c diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 1f49c288457b..e06e1a99eafa 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -12,6 +12,7 @@ config ARM64 select ARM_ARCH_TIMER select ARM_GIC select AUDIT_ARCH_COMPAT_GENERIC + select ARM_GIC_V2M if PCI_MSI select ARM_GIC_V3 select ARM_GIC_V3_ITS if PCI_MSI select BUILDTIME_EXTABLE_SORT diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig index d47fa846763b..e72e23960632 100644 --- a/drivers/irqchip/Kconfig +++ b/drivers/irqchip/Kconfig @@ -8,6 +8,12 @@ config ARM_GIC select IRQ_DOMAIN_HIERARCHY select MULTI_IRQ_HANDLER +config ARM_GIC_V2M + bool + depends on ARM_GIC + depends on PCI && PCI_MSI + select PCI_MSI_IRQ_DOMAIN + config GIC_NON_BANKED bool diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile index 2029e79c07a9..983634d61b25 100644 --- a/drivers/irqchip/Makefile +++ b/drivers/irqchip/Makefile @@ -19,6 +19,7 @@ obj-$(CONFIG_ARCH_SUNXI) += irq-sun4i.o obj-$(CONFIG_ARCH_SUNXI) += irq-sunxi-nmi.o obj-$(CONFIG_ARCH_SPEAR3XX) += spear-shirq.o obj-$(CONFIG_ARM_GIC) += irq-gic.o irq-gic-common.o +obj-$(CONFIG_ARM_GIC_V2M) += irq-gic-v2m.o obj-$(CONFIG_ARM_GIC_V3) += irq-gic-v3.o irq-gic-common.o obj-$(CONFIG_ARM_GIC_V3_ITS) += irq-gic-v3-its.o obj-$(CONFIG_ARM_NVIC) += irq-nvic.o diff --git a/drivers/irqchip/irq-gic-v2m.c b/drivers/irqchip/irq-gic-v2m.c new file mode 100644 index 000000000000..fdf706555d72 --- /dev/null +++ b/drivers/irqchip/irq-gic-v2m.c @@ -0,0 +1,333 @@ +/* + * ARM GIC v2m MSI(-X) support + * Support for Message Signaled Interrupts for systems that + * implement ARM Generic Interrupt Controller: GICv2m. + * + * Copyright (C) 2014 Advanced Micro Devices, Inc. + * Authors: Suravee Suthikulpanit + * Harish Kasiviswanathan + * Brandon Anderson + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published + * by the Free Software Foundation. + */ + +#define pr_fmt(fmt) "GICv2m: " fmt + +#include +#include +#include +#include +#include +#include +#include + +/* +* MSI_TYPER: +* [31:26] Reserved +* [25:16] lowest SPI assigned to MSI +* [15:10] Reserved +* [9:0] Numer of SPIs assigned to MSI +*/ +#define V2M_MSI_TYPER 0x008 +#define V2M_MSI_TYPER_BASE_SHIFT 16 +#define V2M_MSI_TYPER_BASE_MASK 0x3FF +#define V2M_MSI_TYPER_NUM_MASK 0x3FF +#define V2M_MSI_SETSPI_NS 0x040 +#define V2M_MIN_SPI 32 +#define V2M_MAX_SPI 1019 + +#define V2M_MSI_TYPER_BASE_SPI(x) \ + (((x) >> V2M_MSI_TYPER_BASE_SHIFT) & V2M_MSI_TYPER_BASE_MASK) + +#define V2M_MSI_TYPER_NUM_SPI(x) ((x) & V2M_MSI_TYPER_NUM_MASK) + +struct v2m_data { + spinlock_t msi_cnt_lock; + struct msi_controller mchip; + struct resource res; /* GICv2m resource */ + void __iomem *base; /* GICv2m virt address */ + u32 spi_start; /* The SPI number that MSIs start */ + u32 nr_spis; /* The number of SPIs for MSIs */ + unsigned long *bm; /* MSI vector bitmap */ + struct irq_domain *domain; +}; + +static void gicv2m_mask_msi_irq(struct irq_data *d) +{ + pci_msi_mask_irq(d); + irq_chip_mask_parent(d); +} + +static void gicv2m_unmask_msi_irq(struct irq_data *d) +{ + pci_msi_unmask_irq(d); + irq_chip_unmask_parent(d); +} + +static struct irq_chip gicv2m_msi_irq_chip = { + .name = "MSI", + .irq_mask = gicv2m_mask_msi_irq, + .irq_unmask = gicv2m_unmask_msi_irq, + .irq_eoi = irq_chip_eoi_parent, + .irq_write_msi_msg = pci_msi_domain_write_msg, +}; + +static struct msi_domain_info gicv2m_msi_domain_info = { + .flags = (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS | + MSI_FLAG_PCI_MSIX), + .chip = &gicv2m_msi_irq_chip, +}; + +static int gicv2m_set_affinity(struct irq_data *irq_data, + const struct cpumask *mask, bool force) +{ + int ret; + + ret = irq_chip_set_affinity_parent(irq_data, mask, force); + if (ret == IRQ_SET_MASK_OK) + ret = IRQ_SET_MASK_OK_DONE; + + return ret; +} + +static void gicv2m_compose_msi_msg(struct irq_data *data, struct msi_msg *msg) +{ + struct v2m_data *v2m = irq_data_get_irq_chip_data(data); + phys_addr_t addr = v2m->res.start + V2M_MSI_SETSPI_NS; + + msg->address_hi = (u32) (addr >> 32); + msg->address_lo = (u32) (addr); + msg->data = data->hwirq; +} + +static struct irq_chip gicv2m_irq_chip = { + .name = "GICv2m", + .irq_mask = irq_chip_mask_parent, + .irq_unmask = irq_chip_unmask_parent, + .irq_eoi = irq_chip_eoi_parent, + .irq_set_affinity = gicv2m_set_affinity, + .irq_compose_msi_msg = gicv2m_compose_msi_msg, +}; + +static int gicv2m_irq_gic_domain_alloc(struct irq_domain *domain, + unsigned int virq, + irq_hw_number_t hwirq) +{ + struct of_phandle_args args; + struct irq_data *d; + int err; + + args.np = domain->parent->of_node; + args.args_count = 3; + args.args[0] = 0; + args.args[1] = hwirq - 32; + args.args[2] = IRQ_TYPE_EDGE_RISING; + + err = irq_domain_alloc_irqs_parent(domain, virq, 1, &args); + if (err) + return err; + + /* Configure the interrupt line to be edge */ + d = irq_domain_get_irq_data(domain->parent, virq); + d->chip->irq_set_type(d, IRQ_TYPE_EDGE_RISING); + return 0; +} + +static void gicv2m_unalloc_msi(struct v2m_data *v2m, unsigned int hwirq) +{ + int pos; + + pos = hwirq - v2m->spi_start; + if (pos < 0 || pos >= v2m->nr_spis) { + pr_err("Failed to teardown msi. Invalid hwirq %d\n", hwirq); + return; + } + + spin_lock(&v2m->msi_cnt_lock); + __clear_bit(pos, v2m->bm); + spin_unlock(&v2m->msi_cnt_lock); +} + +static int gicv2m_irq_domain_alloc(struct irq_domain *domain, unsigned int virq, + unsigned int nr_irqs, void *args) +{ + struct v2m_data *v2m = domain->host_data; + int hwirq, offset, err = 0; + + spin_lock(&v2m->msi_cnt_lock); + offset = find_first_zero_bit(v2m->bm, v2m->nr_spis); + if (offset < v2m->nr_spis) + __set_bit(offset, v2m->bm); + else + err = -ENOSPC; + spin_unlock(&v2m->msi_cnt_lock); + + if (err) + return err; + + hwirq = v2m->spi_start + offset; + + err = gicv2m_irq_gic_domain_alloc(domain, virq, hwirq); + if (err) { + gicv2m_unalloc_msi(v2m, hwirq); + return err; + } + + irq_domain_set_hwirq_and_chip(domain, virq, hwirq, + &gicv2m_irq_chip, v2m); + + return 0; +} + +static void gicv2m_irq_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 v2m_data *v2m = irq_data_get_irq_chip_data(d); + + BUG_ON(nr_irqs != 1); + gicv2m_unalloc_msi(v2m, d->hwirq); + irq_domain_free_irqs_parent(domain, virq, nr_irqs); +} + +static const struct irq_domain_ops gicv2m_domain_ops = { + .alloc = gicv2m_irq_domain_alloc, + .free = gicv2m_irq_domain_free, +}; + +static bool is_msi_spi_valid(u32 base, u32 num) +{ + if (base < V2M_MIN_SPI) { + pr_err("Invalid MSI base SPI (base:%u)\n", base); + return false; + } + + if ((num == 0) || (base + num > V2M_MAX_SPI)) { + pr_err("Number of SPIs (%u) exceed maximum (%u)\n", + num, V2M_MAX_SPI - V2M_MIN_SPI + 1); + return false; + } + + return true; +} + +static int __init gicv2m_init_one(struct device_node *node, + struct irq_domain *parent) +{ + int ret; + struct v2m_data *v2m; + + v2m = kzalloc(sizeof(struct v2m_data), GFP_KERNEL); + if (!v2m) { + pr_err("Failed to allocate struct v2m_data.\n"); + return -ENOMEM; + } + + ret = of_address_to_resource(node, 0, &v2m->res); + if (ret) { + pr_err("Failed to allocate v2m resource.\n"); + goto err_free_v2m; + } + + v2m->base = ioremap(v2m->res.start, resource_size(&v2m->res)); + if (!v2m->base) { + pr_err("Failed to map GICv2m resource\n"); + ret = -ENOMEM; + goto err_free_v2m; + } + + if (!of_property_read_u32(node, "arm,msi-base-spi", &v2m->spi_start) && + !of_property_read_u32(node, "arm,msi-num-spis", &v2m->nr_spis)) { + pr_info("Overriding V2M MSI_TYPER (base:%u, num:%u)\n", + v2m->spi_start, v2m->nr_spis); + } else { + u32 typer = readl_relaxed(v2m->base + V2M_MSI_TYPER); + + v2m->spi_start = V2M_MSI_TYPER_BASE_SPI(typer); + v2m->nr_spis = V2M_MSI_TYPER_NUM_SPI(typer); + } + + if (!is_msi_spi_valid(v2m->spi_start, v2m->nr_spis)) { + ret = -EINVAL; + goto err_iounmap; + } + + v2m->bm = kzalloc(sizeof(long) * BITS_TO_LONGS(v2m->nr_spis), + GFP_KERNEL); + if (!v2m->bm) { + ret = -ENOMEM; + goto err_iounmap; + } + + v2m->domain = irq_domain_add_tree(NULL, &gicv2m_domain_ops, v2m); + if (!v2m->domain) { + pr_err("Failed to create GICv2m domain\n"); + ret = -ENOMEM; + goto err_free_bm; + } + + v2m->domain->parent = parent; + v2m->mchip.of_node = node; + v2m->mchip.domain = pci_msi_create_irq_domain(node, + &gicv2m_msi_domain_info, + v2m->domain); + if (!v2m->mchip.domain) { + pr_err("Failed to create MSI domain\n"); + ret = -ENOMEM; + goto err_free_domains; + } + + spin_lock_init(&v2m->msi_cnt_lock); + + ret = of_pci_msi_chip_add(&v2m->mchip); + if (ret) { + pr_err("Failed to add msi_chip.\n"); + goto err_free_domains; + } + + pr_info("Node %s: range[%#lx:%#lx], SPI[%d:%d]\n", node->name, + (unsigned long)v2m->res.start, (unsigned long)v2m->res.end, + v2m->spi_start, (v2m->spi_start + v2m->nr_spis)); + + return 0; + +err_free_domains: + if (v2m->mchip.domain) + irq_domain_remove(v2m->mchip.domain); + if (v2m->domain) + irq_domain_remove(v2m->domain); +err_free_bm: + kfree(v2m->bm); +err_iounmap: + iounmap(v2m->base); +err_free_v2m: + kfree(v2m); + return ret; +} + +static struct of_device_id gicv2m_device_id[] = { + { .compatible = "arm,gic-v2m-frame", }, + {}, +}; + +int __init gicv2m_of_init(struct device_node *node, struct irq_domain *parent) +{ + int ret = 0; + struct device_node *child; + + for (child = of_find_matching_node(node, gicv2m_device_id); child; + child = of_find_matching_node(child, gicv2m_device_id)) { + if (!of_find_property(child, "msi-controller", NULL)) + continue; + + ret = gicv2m_init_one(child, parent); + if (ret) { + of_node_put(node); + break; + } + } + + return ret; +} diff --git a/drivers/irqchip/irq-gic.c b/drivers/irqchip/irq-gic.c index ab6069b09c94..5a71be79786d 100644 --- a/drivers/irqchip/irq-gic.c +++ b/drivers/irqchip/irq-gic.c @@ -1066,6 +1066,10 @@ gic_of_init(struct device_node *node, struct device_node *parent) irq = irq_of_parse_and_map(node, 0); gic_cascade_irq(gic_cnt, irq); } + + if (IS_ENABLED(CONFIG_ARM_GIC_V2M)) + gicv2m_of_init(node, gic_data[gic_cnt].domain); + gic_cnt++; return 0; } diff --git a/include/linux/irqchip/arm-gic.h b/include/linux/irqchip/arm-gic.h index 13eed92c7d24..60b09ed58cae 100644 --- a/include/linux/irqchip/arm-gic.h +++ b/include/linux/irqchip/arm-gic.h @@ -106,6 +106,8 @@ static inline void gic_init(unsigned int nr, int start, gic_init_bases(nr, start, dist, cpu, 0, NULL); } +int gicv2m_of_init(struct device_node *node, struct irq_domain *parent); + void gic_send_sgi(unsigned int cpu_id, unsigned int irq); int gic_get_cpu_id(unsigned int cpu); void gic_migrate_target(unsigned int new_cpu_id); -- 2.30.2