diff options
Diffstat (limited to 'drivers/irqchip')
| -rw-r--r-- | drivers/irqchip/Kconfig | 6 | ||||
| -rw-r--r-- | drivers/irqchip/Makefile | 1 | ||||
| -rw-r--r-- | drivers/irqchip/irq-alpine-msi.c | 293 |
3 files changed, 300 insertions, 0 deletions
diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig index 00bbec6eca0b..7e8c441ff2de 100644 --- a/drivers/irqchip/Kconfig +++ b/drivers/irqchip/Kconfig @@ -65,6 +65,12 @@ config ARMADA_370_XP_IRQ select GENERIC_IRQ_CHIP select PCI_MSI_IRQ_DOMAIN if PCI_MSI +config ALPINE_MSI + bool + depends on PCI && PCI_MSI + select GENERIC_IRQ_CHIP + select PCI_MSI_IRQ_DOMAIN + config ATMEL_AIC_IRQ bool select GENERIC_IRQ_CHIP diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile index 8698710fda37..b03cfcbbac6b 100644 --- a/drivers/irqchip/Makefile +++ b/drivers/irqchip/Makefile @@ -1,5 +1,6 @@ obj-$(CONFIG_IRQCHIP) += irqchip.o +obj-$(CONFIG_ALPINE_MSI) += irq-alpine-msi.o obj-$(CONFIG_ATH79) += irq-ath79-cpu.o obj-$(CONFIG_ATH79) += irq-ath79-misc.o obj-$(CONFIG_ARCH_BCM2835) += irq-bcm2835.o diff --git a/drivers/irqchip/irq-alpine-msi.c b/drivers/irqchip/irq-alpine-msi.c new file mode 100644 index 000000000000..f8712722a606 --- /dev/null +++ b/drivers/irqchip/irq-alpine-msi.c @@ -0,0 +1,293 @@ +/* + * Annapurna Labs MSIX support services + * + * Copyright (C) 2016, Amazon.com, Inc. or its affiliates. All Rights Reserved. + * + * Antoine Tenart <antoine.tenart@free-electrons.com> + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/irqchip.h> +#include <linux/irqchip/arm-gic.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> + +#include <asm/irq.h> +#include <asm-generic/msi.h> + +/* MSIX message address format: local GIC target */ +#define ALPINE_MSIX_SPI_TARGET_CLUSTER0 BIT(16) + +struct alpine_msix_data { + spinlock_t msi_map_lock; + phys_addr_t addr; + u32 spi_first; /* The SGI number that MSIs start */ + u32 num_spis; /* The number of SGIs for MSIs */ + unsigned long *msi_map; +}; + +static void alpine_msix_mask_msi_irq(struct irq_data *d) +{ + pci_msi_mask_irq(d); + irq_chip_mask_parent(d); +} + +static void alpine_msix_unmask_msi_irq(struct irq_data *d) +{ + pci_msi_unmask_irq(d); + irq_chip_unmask_parent(d); +} + +static struct irq_chip alpine_msix_irq_chip = { + .name = "MSIx", + .irq_mask = alpine_msix_mask_msi_irq, + .irq_unmask = alpine_msix_unmask_msi_irq, + .irq_eoi = irq_chip_eoi_parent, + .irq_set_affinity = irq_chip_set_affinity_parent, +}; + +static int alpine_msix_allocate_sgi(struct alpine_msix_data *priv, int num_req) +{ + int first; + + spin_lock(&priv->msi_map_lock); + + first = bitmap_find_next_zero_area(priv->msi_map, priv->num_spis, 0, + num_req, 0); + if (first >= priv->num_spis) { + spin_unlock(&priv->msi_map_lock); + return -ENOSPC; + } + + bitmap_set(priv->msi_map, first, num_req); + + spin_unlock(&priv->msi_map_lock); + + return priv->spi_first + first; +} + +static void alpine_msix_free_sgi(struct alpine_msix_data *priv, unsigned sgi, + int num_req) +{ + int first = sgi - priv->spi_first; + + spin_lock(&priv->msi_map_lock); + + bitmap_clear(priv->msi_map, first, num_req); + + spin_unlock(&priv->msi_map_lock); +} + +static void alpine_msix_compose_msi_msg(struct irq_data *data, + struct msi_msg *msg) +{ + struct alpine_msix_data *priv = irq_data_get_irq_chip_data(data); + phys_addr_t msg_addr = priv->addr; + + msg_addr |= (data->hwirq << 3); + + msg->address_hi = upper_32_bits(msg_addr); + msg->address_lo = lower_32_bits(msg_addr); + msg->data = 0; +} + +static struct msi_domain_info alpine_msix_domain_info = { + .flags = MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS | + MSI_FLAG_PCI_MSIX, + .chip = &alpine_msix_irq_chip, +}; + +static struct irq_chip middle_irq_chip = { + .name = "alpine_msix_middle", + .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_compose_msi_msg = alpine_msix_compose_msi_msg, +}; + +static int alpine_msix_gic_domain_alloc(struct irq_domain *domain, + unsigned int virq, int sgi) +{ + struct irq_fwspec fwspec; + struct irq_data *d; + int ret; + + if (!is_of_node(domain->parent->fwnode)) + return -EINVAL; + + fwspec.fwnode = domain->parent->fwnode; + fwspec.param_count = 3; + fwspec.param[0] = 0; + fwspec.param[1] = sgi; + fwspec.param[2] = IRQ_TYPE_EDGE_RISING; + + ret = irq_domain_alloc_irqs_parent(domain, virq, 1, &fwspec); + if (ret) + return ret; + + d = irq_domain_get_irq_data(domain->parent, virq); + d->chip->irq_set_type(d, IRQ_TYPE_EDGE_RISING); + + return 0; +} + +static int alpine_msix_middle_domain_alloc(struct irq_domain *domain, + unsigned int virq, + unsigned int nr_irqs, void *args) +{ + struct alpine_msix_data *priv = domain->host_data; + int sgi, err, i; + + sgi = alpine_msix_allocate_sgi(priv, nr_irqs); + if (sgi < 0) + return sgi; + + for (i = 0; i < nr_irqs; i++) { + err = alpine_msix_gic_domain_alloc(domain, virq + i, sgi + i); + if (err) + goto err_sgi; + + irq_domain_set_hwirq_and_chip(domain, virq + i, sgi + i, + &middle_irq_chip, priv); + } + + return 0; + +err_sgi: + while (--i >= 0) + irq_domain_free_irqs_parent(domain, virq, i); + alpine_msix_free_sgi(priv, sgi, nr_irqs); + return err; +} + +static void alpine_msix_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 alpine_msix_data *priv = irq_data_get_irq_chip_data(d); + + irq_domain_free_irqs_parent(domain, virq, nr_irqs); + alpine_msix_free_sgi(priv, d->hwirq, nr_irqs); +} + +static const struct irq_domain_ops alpine_msix_middle_domain_ops = { + .alloc = alpine_msix_middle_domain_alloc, + .free = alpine_msix_middle_domain_free, +}; + +static int alpine_msix_init_domains(struct alpine_msix_data *priv, + struct device_node *node) +{ + struct irq_domain *middle_domain, *msi_domain, *gic_domain; + struct device_node *gic_node; + + gic_node = of_irq_find_parent(node); + if (!gic_node) { + pr_err("Failed to find the GIC node\n"); + return -ENODEV; + } + + gic_domain = irq_find_host(gic_node); + if (!gic_domain) { + pr_err("Failed to find the GIC domain\n"); + return -ENXIO; + } + + middle_domain = irq_domain_add_tree(NULL, + &alpine_msix_middle_domain_ops, + priv); + if (!middle_domain) { + pr_err("Failed to create the MSIX middle domain\n"); + return -ENOMEM; + } + + middle_domain->parent = gic_domain; + + msi_domain = pci_msi_create_irq_domain(of_node_to_fwnode(node), + &alpine_msix_domain_info, + middle_domain); + if (!msi_domain) { + pr_err("Failed to create MSI domain\n"); + irq_domain_remove(msi_domain); + return -ENOMEM; + } + + return 0; +} + +static int alpine_msix_init(struct device_node *node, + struct device_node *parent) +{ + struct alpine_msix_data *priv; + struct resource res; + int ret; + + priv = kzalloc(sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + spin_lock_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; + } + + /* + * The 20 least significant bits of addr provide direct information + * regarding the interrupt destination. + * + * To select the primary GIC as the target GIC, bits [18:17] must be set + * to 0x0. In this case, bit 16 (SPI_TARGET_CLUSTER0) must be set. + */ + priv->addr = res.start & GENMASK_ULL(63,20); + priv->addr |= ALPINE_MSIX_SPI_TARGET_CLUSTER0; + + if (of_property_read_u32(node, "al,msi-base-spi", &priv->spi_first)) { + pr_err("Unable to parse MSI base\n"); + ret = -EINVAL; + goto err_priv; + } + + if (of_property_read_u32(node, "al,msi-num-spis", &priv->num_spis)) { + pr_err("Unable to parse MSI numbers\n"); + ret = -EINVAL; + goto err_priv; + } + + priv->msi_map = kzalloc(sizeof(*priv->msi_map) * BITS_TO_LONGS(priv->num_spis), + GFP_KERNEL); + if (!priv->msi_map) { + ret = -ENOMEM; + goto err_priv; + } + + pr_debug("Registering %d msixs, starting at %d\n", + priv->num_spis, priv->spi_first); + + ret = alpine_msix_init_domains(priv, node); + if (ret) + goto err_map; + + return 0; + +err_map: + kfree(priv->msi_map); +err_priv: + kfree(priv); + return ret; +} +IRQCHIP_DECLARE(alpine_msix, "al,alpine-msix", alpine_msix_init); |