1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Freescale Management Complex (MC) bus driver MSI support 4 * 5 * Copyright (C) 2015-2016 Freescale Semiconductor, Inc. 6 * Author: German Rivera <German.Rivera@freescale.com> 7 * 8 */ 9 10 #include <linux/of_device.h> 11 #include <linux/of_address.h> 12 #include <linux/irq.h> 13 #include <linux/msi.h> 14 #include <linux/of.h> 15 #include <linux/of_irq.h> 16 #include <linux/fsl/mc.h> 17 18 static struct irq_chip its_msi_irq_chip = { 19 .name = "ITS-fMSI", 20 .irq_mask = irq_chip_mask_parent, 21 .irq_unmask = irq_chip_unmask_parent, 22 .irq_eoi = irq_chip_eoi_parent, 23 .irq_set_affinity = msi_domain_set_affinity 24 }; 25 26 static u32 fsl_mc_msi_domain_get_msi_id(struct irq_domain *domain, 27 struct fsl_mc_device *mc_dev) 28 { 29 struct device_node *of_node; 30 u32 out_id; 31 32 of_node = irq_domain_get_of_node(domain); 33 out_id = of_msi_map_id(&mc_dev->dev, of_node, mc_dev->icid); 34 35 return out_id; 36 } 37 38 static int its_fsl_mc_msi_prepare(struct irq_domain *msi_domain, 39 struct device *dev, 40 int nvec, msi_alloc_info_t *info) 41 { 42 struct fsl_mc_device *mc_bus_dev; 43 struct msi_domain_info *msi_info; 44 45 if (!dev_is_fsl_mc(dev)) 46 return -EINVAL; 47 48 mc_bus_dev = to_fsl_mc_device(dev); 49 if (!(mc_bus_dev->flags & FSL_MC_IS_DPRC)) 50 return -EINVAL; 51 52 /* 53 * Set the device Id to be passed to the GIC-ITS: 54 * 55 * NOTE: This device id corresponds to the IOMMU stream ID 56 * associated with the DPRC object (ICID). 57 */ 58 info->scratchpad[0].ul = fsl_mc_msi_domain_get_msi_id(msi_domain, 59 mc_bus_dev); 60 msi_info = msi_get_domain_info(msi_domain->parent); 61 62 /* Allocate at least 32 MSIs, and always as a power of 2 */ 63 nvec = max_t(int, 32, roundup_pow_of_two(nvec)); 64 return msi_info->ops->msi_prepare(msi_domain->parent, dev, nvec, info); 65 } 66 67 static struct msi_domain_ops its_fsl_mc_msi_ops __ro_after_init = { 68 .msi_prepare = its_fsl_mc_msi_prepare, 69 }; 70 71 static struct msi_domain_info its_fsl_mc_msi_domain_info = { 72 .flags = (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS), 73 .ops = &its_fsl_mc_msi_ops, 74 .chip = &its_msi_irq_chip, 75 }; 76 77 static const struct of_device_id its_device_id[] = { 78 { .compatible = "arm,gic-v3-its", }, 79 {}, 80 }; 81 82 static int __init its_fsl_mc_msi_init(void) 83 { 84 struct device_node *np; 85 struct irq_domain *parent; 86 struct irq_domain *mc_msi_domain; 87 88 for (np = of_find_matching_node(NULL, its_device_id); np; 89 np = of_find_matching_node(np, its_device_id)) { 90 if (!of_device_is_available(np)) 91 continue; 92 if (!of_property_read_bool(np, "msi-controller")) 93 continue; 94 95 parent = irq_find_matching_host(np, DOMAIN_BUS_NEXUS); 96 if (!parent || !msi_get_domain_info(parent)) { 97 pr_err("%pOF: unable to locate ITS domain\n", np); 98 continue; 99 } 100 101 mc_msi_domain = fsl_mc_msi_create_irq_domain( 102 of_node_to_fwnode(np), 103 &its_fsl_mc_msi_domain_info, 104 parent); 105 if (!mc_msi_domain) { 106 pr_err("%pOF: unable to create fsl-mc domain\n", np); 107 continue; 108 } 109 110 pr_info("fsl-mc MSI: %pOF domain created\n", np); 111 } 112 113 return 0; 114 } 115 116 early_initcall(its_fsl_mc_msi_init); 117