diff options
Diffstat (limited to 'drivers/irqchip/irq-gic-v3-its-fsl-mc-msi.c')
| -rw-r--r-- | drivers/irqchip/irq-gic-v3-its-fsl-mc-msi.c | 170 |
1 files changed, 170 insertions, 0 deletions
diff --git a/drivers/irqchip/irq-gic-v3-its-fsl-mc-msi.c b/drivers/irqchip/irq-gic-v3-its-fsl-mc-msi.c new file mode 100644 index 000000000..634263dfd --- /dev/null +++ b/drivers/irqchip/irq-gic-v3-its-fsl-mc-msi.c @@ -0,0 +1,170 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Freescale Management Complex (MC) bus driver MSI support + * + * Copyright (C) 2015-2016 Freescale Semiconductor, Inc. + * Author: German Rivera <German.Rivera@freescale.com> + * + */ + +#include <linux/acpi.h> +#include <linux/acpi_iort.h> +#include <linux/of_device.h> +#include <linux/of_address.h> +#include <linux/irq.h> +#include <linux/msi.h> +#include <linux/of.h> +#include <linux/of_irq.h> +#include <linux/fsl/mc.h> + +static struct irq_chip its_msi_irq_chip = { + .name = "ITS-fMSI", + .irq_mask = irq_chip_mask_parent, + .irq_unmask = irq_chip_unmask_parent, + .irq_eoi = irq_chip_eoi_parent, + .irq_set_affinity = msi_domain_set_affinity +}; + +static u32 fsl_mc_msi_domain_get_msi_id(struct irq_domain *domain, + struct fsl_mc_device *mc_dev) +{ + struct device_node *of_node; + u32 out_id; + + of_node = irq_domain_get_of_node(domain); + out_id = of_node ? of_msi_map_id(&mc_dev->dev, of_node, mc_dev->icid) : + iort_msi_map_id(&mc_dev->dev, mc_dev->icid); + + return out_id; +} + +static int its_fsl_mc_msi_prepare(struct irq_domain *msi_domain, + struct device *dev, + int nvec, msi_alloc_info_t *info) +{ + struct fsl_mc_device *mc_bus_dev; + struct msi_domain_info *msi_info; + + if (!dev_is_fsl_mc(dev)) + return -EINVAL; + + mc_bus_dev = to_fsl_mc_device(dev); + if (!(mc_bus_dev->flags & FSL_MC_IS_DPRC)) + return -EINVAL; + + /* + * Set the device Id to be passed to the GIC-ITS: + * + * NOTE: This device id corresponds to the IOMMU stream ID + * associated with the DPRC object (ICID). + */ + info->scratchpad[0].ul = fsl_mc_msi_domain_get_msi_id(msi_domain, + mc_bus_dev); + msi_info = msi_get_domain_info(msi_domain->parent); + + /* Allocate at least 32 MSIs, and always as a power of 2 */ + nvec = max_t(int, 32, roundup_pow_of_two(nvec)); + return msi_info->ops->msi_prepare(msi_domain->parent, dev, nvec, info); +} + +static struct msi_domain_ops its_fsl_mc_msi_ops __ro_after_init = { + .msi_prepare = its_fsl_mc_msi_prepare, +}; + +static struct msi_domain_info its_fsl_mc_msi_domain_info = { + .flags = (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS), + .ops = &its_fsl_mc_msi_ops, + .chip = &its_msi_irq_chip, +}; + +static const struct of_device_id its_device_id[] = { + { .compatible = "arm,gic-v3-its", }, + {}, +}; + +static void __init its_fsl_mc_msi_init_one(struct fwnode_handle *handle, + const char *name) +{ + struct irq_domain *parent; + struct irq_domain *mc_msi_domain; + + parent = irq_find_matching_fwnode(handle, DOMAIN_BUS_NEXUS); + if (!parent || !msi_get_domain_info(parent)) { + pr_err("%s: unable to locate ITS domain\n", name); + return; + } + + mc_msi_domain = fsl_mc_msi_create_irq_domain(handle, + &its_fsl_mc_msi_domain_info, + parent); + if (!mc_msi_domain) { + pr_err("%s: unable to create fsl-mc domain\n", name); + return; + } + + pr_info("fsl-mc MSI: %s domain created\n", name); +} + +#ifdef CONFIG_ACPI +static int __init +its_fsl_mc_msi_parse_madt(union acpi_subtable_headers *header, + const unsigned long end) +{ + struct acpi_madt_generic_translator *its_entry; + struct fwnode_handle *dom_handle; + const char *node_name; + int err = 0; + + its_entry = (struct acpi_madt_generic_translator *)header; + node_name = kasprintf(GFP_KERNEL, "ITS@0x%lx", + (long)its_entry->base_address); + + dom_handle = iort_find_domain_token(its_entry->translation_id); + if (!dom_handle) { + pr_err("%s: Unable to locate ITS domain handle\n", node_name); + err = -ENXIO; + goto out; + } + + its_fsl_mc_msi_init_one(dom_handle, node_name); + +out: + kfree(node_name); + return err; +} + + +static void __init its_fsl_mc_acpi_msi_init(void) +{ + acpi_table_parse_madt(ACPI_MADT_TYPE_GENERIC_TRANSLATOR, + its_fsl_mc_msi_parse_madt, 0); +} +#else +static inline void its_fsl_mc_acpi_msi_init(void) { } +#endif + +static void __init its_fsl_mc_of_msi_init(void) +{ + struct device_node *np; + + for (np = of_find_matching_node(NULL, its_device_id); np; + np = of_find_matching_node(np, its_device_id)) { + if (!of_device_is_available(np)) + continue; + if (!of_property_read_bool(np, "msi-controller")) + continue; + + its_fsl_mc_msi_init_one(of_node_to_fwnode(np), + np->full_name); + } +} + +static int __init its_fsl_mc_msi_init(void) +{ + its_fsl_mc_of_msi_init(); + its_fsl_mc_acpi_msi_init(); + + return 0; +} + +early_initcall(its_fsl_mc_msi_init); |