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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Copyright (c) 2015, Linaro Limited, Shannon Zhao4 */5 6#include <linux/platform_device.h>7#include <linux/acpi.h>8#include <xen/xen.h>9#include <xen/page.h>10#include <xen/interface/memory.h>11#include <asm/xen/hypervisor.h>12#include <asm/xen/hypercall.h>13 14static int xen_unmap_device_mmio(const struct resource *resources,15 unsigned int count)16{17 unsigned int i, j, nr;18 int rc = 0;19 const struct resource *r;20 struct xen_remove_from_physmap xrp;21 22 for (i = 0; i < count; i++) {23 r = &resources[i];24 nr = DIV_ROUND_UP(resource_size(r), XEN_PAGE_SIZE);25 if ((resource_type(r) != IORESOURCE_MEM) || (nr == 0))26 continue;27 28 for (j = 0; j < nr; j++) {29 xrp.domid = DOMID_SELF;30 xrp.gpfn = XEN_PFN_DOWN(r->start) + j;31 rc = HYPERVISOR_memory_op(XENMEM_remove_from_physmap,32 &xrp);33 if (rc)34 return rc;35 }36 }37 38 return rc;39}40 41static int xen_map_device_mmio(const struct resource *resources,42 unsigned int count)43{44 unsigned int i, j, nr;45 int rc = 0;46 const struct resource *r;47 xen_pfn_t *gpfns;48 xen_ulong_t *idxs;49 int *errs;50 51 for (i = 0; i < count; i++) {52 struct xen_add_to_physmap_range xatp = {53 .domid = DOMID_SELF,54 .space = XENMAPSPACE_dev_mmio55 };56 57 r = &resources[i];58 nr = DIV_ROUND_UP(resource_size(r), XEN_PAGE_SIZE);59 if ((resource_type(r) != IORESOURCE_MEM) || (nr == 0))60 continue;61 62 gpfns = kcalloc(nr, sizeof(xen_pfn_t), GFP_KERNEL);63 idxs = kcalloc(nr, sizeof(xen_ulong_t), GFP_KERNEL);64 errs = kcalloc(nr, sizeof(int), GFP_KERNEL);65 if (!gpfns || !idxs || !errs) {66 kfree(gpfns);67 kfree(idxs);68 kfree(errs);69 rc = -ENOMEM;70 goto unmap;71 }72 73 for (j = 0; j < nr; j++) {74 /*75 * The regions are always mapped 1:1 to DOM0 and this is76 * fine because the memory map for DOM0 is the same as77 * the host (except for the RAM).78 */79 gpfns[j] = XEN_PFN_DOWN(r->start) + j;80 idxs[j] = XEN_PFN_DOWN(r->start) + j;81 }82 83 xatp.size = nr;84 85 set_xen_guest_handle(xatp.gpfns, gpfns);86 set_xen_guest_handle(xatp.idxs, idxs);87 set_xen_guest_handle(xatp.errs, errs);88 89 rc = HYPERVISOR_memory_op(XENMEM_add_to_physmap_range, &xatp);90 kfree(gpfns);91 kfree(idxs);92 kfree(errs);93 if (rc)94 goto unmap;95 }96 97 return rc;98 99unmap:100 xen_unmap_device_mmio(resources, i);101 return rc;102}103 104static int xen_platform_notifier(struct notifier_block *nb,105 unsigned long action, void *data)106{107 struct platform_device *pdev = to_platform_device(data);108 int r = 0;109 110 if (pdev->num_resources == 0 || pdev->resource == NULL)111 return NOTIFY_OK;112 113 switch (action) {114 case BUS_NOTIFY_ADD_DEVICE:115 r = xen_map_device_mmio(pdev->resource, pdev->num_resources);116 break;117 case BUS_NOTIFY_DEL_DEVICE:118 r = xen_unmap_device_mmio(pdev->resource, pdev->num_resources);119 break;120 default:121 return NOTIFY_DONE;122 }123 if (r)124 dev_err(&pdev->dev, "Platform: Failed to %s device %s MMIO!\n",125 action == BUS_NOTIFY_ADD_DEVICE ? "map" :126 (action == BUS_NOTIFY_DEL_DEVICE ? "unmap" : "?"),127 pdev->name);128 129 return NOTIFY_OK;130}131 132static struct notifier_block platform_device_nb = {133 .notifier_call = xen_platform_notifier,134};135 136static int __init register_xen_platform_notifier(void)137{138 if (!xen_initial_domain() || acpi_disabled)139 return 0;140 141 return bus_register_notifier(&platform_bus_type, &platform_device_nb);142}143 144arch_initcall(register_xen_platform_notifier);145 146#ifdef CONFIG_ARM_AMBA147#include <linux/amba/bus.h>148 149static int xen_amba_notifier(struct notifier_block *nb,150 unsigned long action, void *data)151{152 struct amba_device *adev = to_amba_device(data);153 int r = 0;154 155 switch (action) {156 case BUS_NOTIFY_ADD_DEVICE:157 r = xen_map_device_mmio(&adev->res, 1);158 break;159 case BUS_NOTIFY_DEL_DEVICE:160 r = xen_unmap_device_mmio(&adev->res, 1);161 break;162 default:163 return NOTIFY_DONE;164 }165 if (r)166 dev_err(&adev->dev, "AMBA: Failed to %s device %s MMIO!\n",167 action == BUS_NOTIFY_ADD_DEVICE ? "map" :168 (action == BUS_NOTIFY_DEL_DEVICE ? "unmap" : "?"),169 adev->dev.init_name);170 171 return NOTIFY_OK;172}173 174static struct notifier_block amba_device_nb = {175 .notifier_call = xen_amba_notifier,176};177 178static int __init register_xen_amba_notifier(void)179{180 if (!xen_initial_domain() || acpi_disabled)181 return 0;182 183 return bus_register_notifier(&amba_bustype, &amba_device_nb);184}185 186arch_initcall(register_xen_amba_notifier);187#endif188