diff options
Diffstat (limited to 'drivers/xen/arm-device.c')
| -rw-r--r-- | drivers/xen/arm-device.c | 187 |
1 files changed, 187 insertions, 0 deletions
diff --git a/drivers/xen/arm-device.c b/drivers/xen/arm-device.c new file mode 100644 index 000000000..87493f922 --- /dev/null +++ b/drivers/xen/arm-device.c @@ -0,0 +1,187 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2015, Linaro Limited, Shannon Zhao + */ + +#include <linux/platform_device.h> +#include <linux/acpi.h> +#include <xen/xen.h> +#include <xen/page.h> +#include <xen/interface/memory.h> +#include <asm/xen/hypervisor.h> +#include <asm/xen/hypercall.h> + +static int xen_unmap_device_mmio(const struct resource *resources, + unsigned int count) +{ + unsigned int i, j, nr; + int rc = 0; + const struct resource *r; + struct xen_remove_from_physmap xrp; + + for (i = 0; i < count; i++) { + r = &resources[i]; + nr = DIV_ROUND_UP(resource_size(r), XEN_PAGE_SIZE); + if ((resource_type(r) != IORESOURCE_MEM) || (nr == 0)) + continue; + + for (j = 0; j < nr; j++) { + xrp.domid = DOMID_SELF; + xrp.gpfn = XEN_PFN_DOWN(r->start) + j; + rc = HYPERVISOR_memory_op(XENMEM_remove_from_physmap, + &xrp); + if (rc) + return rc; + } + } + + return rc; +} + +static int xen_map_device_mmio(const struct resource *resources, + unsigned int count) +{ + unsigned int i, j, nr; + int rc = 0; + const struct resource *r; + xen_pfn_t *gpfns; + xen_ulong_t *idxs; + int *errs; + + for (i = 0; i < count; i++) { + struct xen_add_to_physmap_range xatp = { + .domid = DOMID_SELF, + .space = XENMAPSPACE_dev_mmio + }; + + r = &resources[i]; + nr = DIV_ROUND_UP(resource_size(r), XEN_PAGE_SIZE); + if ((resource_type(r) != IORESOURCE_MEM) || (nr == 0)) + continue; + + gpfns = kcalloc(nr, sizeof(xen_pfn_t), GFP_KERNEL); + idxs = kcalloc(nr, sizeof(xen_ulong_t), GFP_KERNEL); + errs = kcalloc(nr, sizeof(int), GFP_KERNEL); + if (!gpfns || !idxs || !errs) { + kfree(gpfns); + kfree(idxs); + kfree(errs); + rc = -ENOMEM; + goto unmap; + } + + for (j = 0; j < nr; j++) { + /* + * The regions are always mapped 1:1 to DOM0 and this is + * fine because the memory map for DOM0 is the same as + * the host (except for the RAM). + */ + gpfns[j] = XEN_PFN_DOWN(r->start) + j; + idxs[j] = XEN_PFN_DOWN(r->start) + j; + } + + xatp.size = nr; + + set_xen_guest_handle(xatp.gpfns, gpfns); + set_xen_guest_handle(xatp.idxs, idxs); + set_xen_guest_handle(xatp.errs, errs); + + rc = HYPERVISOR_memory_op(XENMEM_add_to_physmap_range, &xatp); + kfree(gpfns); + kfree(idxs); + kfree(errs); + if (rc) + goto unmap; + } + + return rc; + +unmap: + xen_unmap_device_mmio(resources, i); + return rc; +} + +static int xen_platform_notifier(struct notifier_block *nb, + unsigned long action, void *data) +{ + struct platform_device *pdev = to_platform_device(data); + int r = 0; + + if (pdev->num_resources == 0 || pdev->resource == NULL) + return NOTIFY_OK; + + switch (action) { + case BUS_NOTIFY_ADD_DEVICE: + r = xen_map_device_mmio(pdev->resource, pdev->num_resources); + break; + case BUS_NOTIFY_DEL_DEVICE: + r = xen_unmap_device_mmio(pdev->resource, pdev->num_resources); + break; + default: + return NOTIFY_DONE; + } + if (r) + dev_err(&pdev->dev, "Platform: Failed to %s device %s MMIO!\n", + action == BUS_NOTIFY_ADD_DEVICE ? "map" : + (action == BUS_NOTIFY_DEL_DEVICE ? "unmap" : "?"), + pdev->name); + + return NOTIFY_OK; +} + +static struct notifier_block platform_device_nb = { + .notifier_call = xen_platform_notifier, +}; + +static int __init register_xen_platform_notifier(void) +{ + if (!xen_initial_domain() || acpi_disabled) + return 0; + + return bus_register_notifier(&platform_bus_type, &platform_device_nb); +} + +arch_initcall(register_xen_platform_notifier); + +#ifdef CONFIG_ARM_AMBA +#include <linux/amba/bus.h> + +static int xen_amba_notifier(struct notifier_block *nb, + unsigned long action, void *data) +{ + struct amba_device *adev = to_amba_device(data); + int r = 0; + + switch (action) { + case BUS_NOTIFY_ADD_DEVICE: + r = xen_map_device_mmio(&adev->res, 1); + break; + case BUS_NOTIFY_DEL_DEVICE: + r = xen_unmap_device_mmio(&adev->res, 1); + break; + default: + return NOTIFY_DONE; + } + if (r) + dev_err(&adev->dev, "AMBA: Failed to %s device %s MMIO!\n", + action == BUS_NOTIFY_ADD_DEVICE ? "map" : + (action == BUS_NOTIFY_DEL_DEVICE ? "unmap" : "?"), + adev->dev.init_name); + + return NOTIFY_OK; +} + +static struct notifier_block amba_device_nb = { + .notifier_call = xen_amba_notifier, +}; + +static int __init register_xen_amba_notifier(void) +{ + if (!xen_initial_domain() || acpi_disabled) + return 0; + + return bus_register_notifier(&amba_bustype, &amba_device_nb); +} + +arch_initcall(register_xen_amba_notifier); +#endif |