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 int its_fsl_mc_msi_prepare(struct irq_domain *msi_domain, 27 struct device *dev, 28 int nvec, msi_alloc_info_t *info) 29 { 30 struct fsl_mc_device *mc_bus_dev; 31 struct msi_domain_info *msi_info; 32 33 if (!dev_is_fsl_mc(dev)) 34 return -EINVAL; 35 36 mc_bus_dev = to_fsl_mc_device(dev); 37 if (!(mc_bus_dev->flags & FSL_MC_IS_DPRC)) 38 return -EINVAL; 39 40 /* 41 * Set the device Id to be passed to the GIC-ITS: 42 * 43 * NOTE: This device id corresponds to the IOMMU stream ID 44 * associated with the DPRC object (ICID). 45 */ 46 info->scratchpad[0].ul = mc_bus_dev->icid; 47 msi_info = msi_get_domain_info(msi_domain->parent); 48 49 /* Allocate at least 32 MSIs, and always as a power of 2 */ 50 nvec = max_t(int, 32, roundup_pow_of_two(nvec)); 51 return msi_info->ops->msi_prepare(msi_domain->parent, dev, nvec, info); 52 } 53 54 static struct msi_domain_ops its_fsl_mc_msi_ops __ro_after_init = { 55 .msi_prepare = its_fsl_mc_msi_prepare, 56 }; 57 58 static struct msi_domain_info its_fsl_mc_msi_domain_info = { 59 .flags = (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS), 60 .ops = &its_fsl_mc_msi_ops, 61 .chip = &its_msi_irq_chip, 62 }; 63 64 static const struct of_device_id its_device_id[] = { 65 { .compatible = "arm,gic-v3-its", }, 66 {}, 67 }; 68 69 static int __init its_fsl_mc_msi_init(void) 70 { 71 struct device_node *np; 72 struct irq_domain *parent; 73 struct irq_domain *mc_msi_domain; 74 75 for (np = of_find_matching_node(NULL, its_device_id); np; 76 np = of_find_matching_node(np, its_device_id)) { 77 if (!of_device_is_available(np)) 78 continue; 79 if (!of_property_read_bool(np, "msi-controller")) 80 continue; 81 82 parent = irq_find_matching_host(np, DOMAIN_BUS_NEXUS); 83 if (!parent || !msi_get_domain_info(parent)) { 84 pr_err("%pOF: unable to locate ITS domain\n", np); 85 continue; 86 } 87 88 mc_msi_domain = fsl_mc_msi_create_irq_domain( 89 of_node_to_fwnode(np), 90 &its_fsl_mc_msi_domain_info, 91 parent); 92 if (!mc_msi_domain) { 93 pr_err("%pOF: unable to create fsl-mc domain\n", np); 94 continue; 95 } 96 97 pr_info("fsl-mc MSI: %pOF domain created\n", np); 98 } 99 100 return 0; 101 } 102 103 early_initcall(its_fsl_mc_msi_init); 104