diff options
Diffstat (limited to 'drivers/virtio/virtio_mmio.c')
| -rw-r--r-- | drivers/virtio/virtio_mmio.c | 842 |
1 files changed, 842 insertions, 0 deletions
diff --git a/drivers/virtio/virtio_mmio.c b/drivers/virtio/virtio_mmio.c new file mode 100644 index 000000000..7fcc307fa --- /dev/null +++ b/drivers/virtio/virtio_mmio.c @@ -0,0 +1,842 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Virtio memory mapped device driver + * + * Copyright 2011-2014, ARM Ltd. + * + * This module allows virtio devices to be used over a virtual, memory mapped + * platform device. + * + * The guest device(s) may be instantiated in one of three equivalent ways: + * + * 1. Static platform device in board's code, eg.: + * + * static struct platform_device v2m_virtio_device = { + * .name = "virtio-mmio", + * .id = -1, + * .num_resources = 2, + * .resource = (struct resource []) { + * { + * .start = 0x1001e000, + * .end = 0x1001e0ff, + * .flags = IORESOURCE_MEM, + * }, { + * .start = 42 + 32, + * .end = 42 + 32, + * .flags = IORESOURCE_IRQ, + * }, + * } + * }; + * + * 2. Device Tree node, eg.: + * + * virtio_block@1e000 { + * compatible = "virtio,mmio"; + * reg = <0x1e000 0x100>; + * interrupts = <42>; + * } + * + * 3. Kernel module (or command line) parameter. Can be used more than once - + * one device will be created for each one. Syntax: + * + * [virtio_mmio.]device=<size>@<baseaddr>:<irq>[:<id>] + * where: + * <size> := size (can use standard suffixes like K, M or G) + * <baseaddr> := physical base address + * <irq> := interrupt number (as passed to request_irq()) + * <id> := (optional) platform device id + * eg.: + * virtio_mmio.device=0x100@0x100b0000:48 \ + * virtio_mmio.device=1K@0x1001e000:74 + * + * Based on Virtio PCI driver by Anthony Liguori, copyright IBM Corp. 2007 + */ + +#define pr_fmt(fmt) "virtio-mmio: " fmt + +#include <linux/acpi.h> +#include <linux/dma-mapping.h> +#include <linux/highmem.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/list.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/pm.h> +#include <linux/slab.h> +#include <linux/spinlock.h> +#include <linux/virtio.h> +#include <linux/virtio_config.h> +#include <uapi/linux/virtio_mmio.h> +#include <linux/virtio_ring.h> + + + +/* The alignment to use between consumer and producer parts of vring. + * Currently hardcoded to the page size. */ +#define VIRTIO_MMIO_VRING_ALIGN PAGE_SIZE + + + +#define to_virtio_mmio_device(_plat_dev) \ + container_of(_plat_dev, struct virtio_mmio_device, vdev) + +struct virtio_mmio_device { + struct virtio_device vdev; + struct platform_device *pdev; + + void __iomem *base; + unsigned long version; + + /* a list of queues so we can dispatch IRQs */ + spinlock_t lock; + struct list_head virtqueues; +}; + +struct virtio_mmio_vq_info { + /* the actual virtqueue */ + struct virtqueue *vq; + + /* the list node for the virtqueues list */ + struct list_head node; +}; + + + +/* Configuration interface */ + +static u64 vm_get_features(struct virtio_device *vdev) +{ + struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev); + u64 features; + + writel(1, vm_dev->base + VIRTIO_MMIO_DEVICE_FEATURES_SEL); + features = readl(vm_dev->base + VIRTIO_MMIO_DEVICE_FEATURES); + features <<= 32; + + writel(0, vm_dev->base + VIRTIO_MMIO_DEVICE_FEATURES_SEL); + features |= readl(vm_dev->base + VIRTIO_MMIO_DEVICE_FEATURES); + + return features; +} + +static int vm_finalize_features(struct virtio_device *vdev) +{ + struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev); + + /* Give virtio_ring a chance to accept features. */ + vring_transport_features(vdev); + + /* Make sure there is are no mixed devices */ + if (vm_dev->version == 2 && + !__virtio_test_bit(vdev, VIRTIO_F_VERSION_1)) { + dev_err(&vdev->dev, "New virtio-mmio devices (version 2) must provide VIRTIO_F_VERSION_1 feature!\n"); + return -EINVAL; + } + + writel(1, vm_dev->base + VIRTIO_MMIO_DRIVER_FEATURES_SEL); + writel((u32)(vdev->features >> 32), + vm_dev->base + VIRTIO_MMIO_DRIVER_FEATURES); + + writel(0, vm_dev->base + VIRTIO_MMIO_DRIVER_FEATURES_SEL); + writel((u32)vdev->features, + vm_dev->base + VIRTIO_MMIO_DRIVER_FEATURES); + + return 0; +} + +static void vm_get(struct virtio_device *vdev, unsigned offset, + void *buf, unsigned len) +{ + struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev); + void __iomem *base = vm_dev->base + VIRTIO_MMIO_CONFIG; + u8 b; + __le16 w; + __le32 l; + + if (vm_dev->version == 1) { + u8 *ptr = buf; + int i; + + for (i = 0; i < len; i++) + ptr[i] = readb(base + offset + i); + return; + } + + switch (len) { + case 1: + b = readb(base + offset); + memcpy(buf, &b, sizeof b); + break; + case 2: + w = cpu_to_le16(readw(base + offset)); + memcpy(buf, &w, sizeof w); + break; + case 4: + l = cpu_to_le32(readl(base + offset)); + memcpy(buf, &l, sizeof l); + break; + case 8: + l = cpu_to_le32(readl(base + offset)); + memcpy(buf, &l, sizeof l); + l = cpu_to_le32(ioread32(base + offset + sizeof l)); + memcpy(buf + sizeof l, &l, sizeof l); + break; + default: + BUG(); + } +} + +static void vm_set(struct virtio_device *vdev, unsigned offset, + const void *buf, unsigned len) +{ + struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev); + void __iomem *base = vm_dev->base + VIRTIO_MMIO_CONFIG; + u8 b; + __le16 w; + __le32 l; + + if (vm_dev->version == 1) { + const u8 *ptr = buf; + int i; + + for (i = 0; i < len; i++) + writeb(ptr[i], base + offset + i); + + return; + } + + switch (len) { + case 1: + memcpy(&b, buf, sizeof b); + writeb(b, base + offset); + break; + case 2: + memcpy(&w, buf, sizeof w); + writew(le16_to_cpu(w), base + offset); + break; + case 4: + memcpy(&l, buf, sizeof l); + writel(le32_to_cpu(l), base + offset); + break; + case 8: + memcpy(&l, buf, sizeof l); + writel(le32_to_cpu(l), base + offset); + memcpy(&l, buf + sizeof l, sizeof l); + writel(le32_to_cpu(l), base + offset + sizeof l); + break; + default: + BUG(); + } +} + +static u32 vm_generation(struct virtio_device *vdev) +{ + struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev); + + if (vm_dev->version == 1) + return 0; + else + return readl(vm_dev->base + VIRTIO_MMIO_CONFIG_GENERATION); +} + +static u8 vm_get_status(struct virtio_device *vdev) +{ + struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev); + + return readl(vm_dev->base + VIRTIO_MMIO_STATUS) & 0xff; +} + +static void vm_set_status(struct virtio_device *vdev, u8 status) +{ + struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev); + + /* We should never be setting status to 0. */ + BUG_ON(status == 0); + + writel(status, vm_dev->base + VIRTIO_MMIO_STATUS); +} + +static void vm_reset(struct virtio_device *vdev) +{ + struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev); + + /* 0 status means a reset. */ + writel(0, vm_dev->base + VIRTIO_MMIO_STATUS); +} + + + +/* Transport interface */ + +/* the notify function used when creating a virt queue */ +static bool vm_notify(struct virtqueue *vq) +{ + struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vq->vdev); + + /* We write the queue's selector into the notification register to + * signal the other end */ + writel(vq->index, vm_dev->base + VIRTIO_MMIO_QUEUE_NOTIFY); + return true; +} + +/* Notify all virtqueues on an interrupt. */ +static irqreturn_t vm_interrupt(int irq, void *opaque) +{ + struct virtio_mmio_device *vm_dev = opaque; + struct virtio_mmio_vq_info *info; + unsigned long status; + unsigned long flags; + irqreturn_t ret = IRQ_NONE; + + /* Read and acknowledge interrupts */ + status = readl(vm_dev->base + VIRTIO_MMIO_INTERRUPT_STATUS); + writel(status, vm_dev->base + VIRTIO_MMIO_INTERRUPT_ACK); + + if (unlikely(status & VIRTIO_MMIO_INT_CONFIG)) { + virtio_config_changed(&vm_dev->vdev); + ret = IRQ_HANDLED; + } + + if (likely(status & VIRTIO_MMIO_INT_VRING)) { + spin_lock_irqsave(&vm_dev->lock, flags); + list_for_each_entry(info, &vm_dev->virtqueues, node) + ret |= vring_interrupt(irq, info->vq); + spin_unlock_irqrestore(&vm_dev->lock, flags); + } + + return ret; +} + + + +static void vm_del_vq(struct virtqueue *vq) +{ + struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vq->vdev); + struct virtio_mmio_vq_info *info = vq->priv; + unsigned long flags; + unsigned int index = vq->index; + + spin_lock_irqsave(&vm_dev->lock, flags); + list_del(&info->node); + spin_unlock_irqrestore(&vm_dev->lock, flags); + + /* Select and deactivate the queue */ + writel(index, vm_dev->base + VIRTIO_MMIO_QUEUE_SEL); + if (vm_dev->version == 1) { + writel(0, vm_dev->base + VIRTIO_MMIO_QUEUE_PFN); + } else { + writel(0, vm_dev->base + VIRTIO_MMIO_QUEUE_READY); + WARN_ON(readl(vm_dev->base + VIRTIO_MMIO_QUEUE_READY)); + } + + vring_del_virtqueue(vq); + + kfree(info); +} + +static void vm_del_vqs(struct virtio_device *vdev) +{ + struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev); + struct virtqueue *vq, *n; + + list_for_each_entry_safe(vq, n, &vdev->vqs, list) + vm_del_vq(vq); + + free_irq(platform_get_irq(vm_dev->pdev, 0), vm_dev); +} + +static struct virtqueue *vm_setup_vq(struct virtio_device *vdev, unsigned index, + void (*callback)(struct virtqueue *vq), + const char *name, bool ctx) +{ + struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev); + struct virtio_mmio_vq_info *info; + struct virtqueue *vq; + unsigned long flags; + unsigned int num; + int err; + + if (!name) + return NULL; + + /* Select the queue we're interested in */ + writel(index, vm_dev->base + VIRTIO_MMIO_QUEUE_SEL); + + /* Queue shouldn't already be set up. */ + if (readl(vm_dev->base + (vm_dev->version == 1 ? + VIRTIO_MMIO_QUEUE_PFN : VIRTIO_MMIO_QUEUE_READY))) { + err = -ENOENT; + goto error_available; + } + + /* Allocate and fill out our active queue description */ + info = kmalloc(sizeof(*info), GFP_KERNEL); + if (!info) { + err = -ENOMEM; + goto error_kmalloc; + } + + num = readl(vm_dev->base + VIRTIO_MMIO_QUEUE_NUM_MAX); + if (num == 0) { + err = -ENOENT; + goto error_new_virtqueue; + } + + /* Create the vring */ + vq = vring_create_virtqueue(index, num, VIRTIO_MMIO_VRING_ALIGN, vdev, + true, true, ctx, vm_notify, callback, name); + if (!vq) { + err = -ENOMEM; + goto error_new_virtqueue; + } + + /* Activate the queue */ + writel(virtqueue_get_vring_size(vq), vm_dev->base + VIRTIO_MMIO_QUEUE_NUM); + if (vm_dev->version == 1) { + u64 q_pfn = virtqueue_get_desc_addr(vq) >> PAGE_SHIFT; + + /* + * virtio-mmio v1 uses a 32bit QUEUE PFN. If we have something + * that doesn't fit in 32bit, fail the setup rather than + * pretending to be successful. + */ + if (q_pfn >> 32) { + dev_err(&vdev->dev, + "platform bug: legacy virtio-mmio must not be used with RAM above 0x%llxGB\n", + 0x1ULL << (32 + PAGE_SHIFT - 30)); + err = -E2BIG; + goto error_bad_pfn; + } + + writel(PAGE_SIZE, vm_dev->base + VIRTIO_MMIO_QUEUE_ALIGN); + writel(q_pfn, vm_dev->base + VIRTIO_MMIO_QUEUE_PFN); + } else { + u64 addr; + + addr = virtqueue_get_desc_addr(vq); + writel((u32)addr, vm_dev->base + VIRTIO_MMIO_QUEUE_DESC_LOW); + writel((u32)(addr >> 32), + vm_dev->base + VIRTIO_MMIO_QUEUE_DESC_HIGH); + + addr = virtqueue_get_avail_addr(vq); + writel((u32)addr, vm_dev->base + VIRTIO_MMIO_QUEUE_AVAIL_LOW); + writel((u32)(addr >> 32), + vm_dev->base + VIRTIO_MMIO_QUEUE_AVAIL_HIGH); + + addr = virtqueue_get_used_addr(vq); + writel((u32)addr, vm_dev->base + VIRTIO_MMIO_QUEUE_USED_LOW); + writel((u32)(addr >> 32), + vm_dev->base + VIRTIO_MMIO_QUEUE_USED_HIGH); + + writel(1, vm_dev->base + VIRTIO_MMIO_QUEUE_READY); + } + + vq->priv = info; + info->vq = vq; + + spin_lock_irqsave(&vm_dev->lock, flags); + list_add(&info->node, &vm_dev->virtqueues); + spin_unlock_irqrestore(&vm_dev->lock, flags); + + return vq; + +error_bad_pfn: + vring_del_virtqueue(vq); +error_new_virtqueue: + if (vm_dev->version == 1) { + writel(0, vm_dev->base + VIRTIO_MMIO_QUEUE_PFN); + } else { + writel(0, vm_dev->base + VIRTIO_MMIO_QUEUE_READY); + WARN_ON(readl(vm_dev->base + VIRTIO_MMIO_QUEUE_READY)); + } + kfree(info); +error_kmalloc: +error_available: + return ERR_PTR(err); +} + +static int vm_find_vqs(struct virtio_device *vdev, unsigned nvqs, + struct virtqueue *vqs[], + vq_callback_t *callbacks[], + const char * const names[], + const bool *ctx, + struct irq_affinity *desc) +{ + struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev); + int irq = platform_get_irq(vm_dev->pdev, 0); + int i, err, queue_idx = 0; + + if (irq < 0) + return irq; + + err = request_irq(irq, vm_interrupt, IRQF_SHARED, + dev_name(&vdev->dev), vm_dev); + if (err) + return err; + + for (i = 0; i < nvqs; ++i) { + if (!names[i]) { + vqs[i] = NULL; + continue; + } + + vqs[i] = vm_setup_vq(vdev, queue_idx++, callbacks[i], names[i], + ctx ? ctx[i] : false); + if (IS_ERR(vqs[i])) { + vm_del_vqs(vdev); + return PTR_ERR(vqs[i]); + } + } + + return 0; +} + +static const char *vm_bus_name(struct virtio_device *vdev) +{ + struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev); + + return vm_dev->pdev->name; +} + +static bool vm_get_shm_region(struct virtio_device *vdev, + struct virtio_shm_region *region, u8 id) +{ + struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev); + u64 len, addr; + + /* Select the region we're interested in */ + writel(id, vm_dev->base + VIRTIO_MMIO_SHM_SEL); + + /* Read the region size */ + len = (u64) readl(vm_dev->base + VIRTIO_MMIO_SHM_LEN_LOW); + len |= (u64) readl(vm_dev->base + VIRTIO_MMIO_SHM_LEN_HIGH) << 32; + + region->len = len; + + /* Check if region length is -1. If that's the case, the shared memory + * region does not exist and there is no need to proceed further. + */ + if (len == ~(u64)0) + return false; + + /* Read the region base address */ + addr = (u64) readl(vm_dev->base + VIRTIO_MMIO_SHM_BASE_LOW); + addr |= (u64) readl(vm_dev->base + VIRTIO_MMIO_SHM_BASE_HIGH) << 32; + + region->addr = addr; + + return true; +} + +static const struct virtio_config_ops virtio_mmio_config_ops = { + .get = vm_get, + .set = vm_set, + .generation = vm_generation, + .get_status = vm_get_status, + .set_status = vm_set_status, + .reset = vm_reset, + .find_vqs = vm_find_vqs, + .del_vqs = vm_del_vqs, + .get_features = vm_get_features, + .finalize_features = vm_finalize_features, + .bus_name = vm_bus_name, + .get_shm_region = vm_get_shm_region, +}; + +#ifdef CONFIG_PM_SLEEP +static int virtio_mmio_freeze(struct device *dev) +{ + struct virtio_mmio_device *vm_dev = dev_get_drvdata(dev); + + return virtio_device_freeze(&vm_dev->vdev); +} + +static int virtio_mmio_restore(struct device *dev) +{ + struct virtio_mmio_device *vm_dev = dev_get_drvdata(dev); + + if (vm_dev->version == 1) + writel(PAGE_SIZE, vm_dev->base + VIRTIO_MMIO_GUEST_PAGE_SIZE); + + return virtio_device_restore(&vm_dev->vdev); +} + +static const struct dev_pm_ops virtio_mmio_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(virtio_mmio_freeze, virtio_mmio_restore) +}; +#endif + +static void virtio_mmio_release_dev(struct device *_d) +{ + struct virtio_device *vdev = + container_of(_d, struct virtio_device, dev); + struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev); + + kfree(vm_dev); +} + +/* Platform device */ + +static int virtio_mmio_probe(struct platform_device *pdev) +{ + struct virtio_mmio_device *vm_dev; + unsigned long magic; + int rc; + + vm_dev = kzalloc(sizeof(*vm_dev), GFP_KERNEL); + if (!vm_dev) + return -ENOMEM; + + vm_dev->vdev.dev.parent = &pdev->dev; + vm_dev->vdev.dev.release = virtio_mmio_release_dev; + vm_dev->vdev.config = &virtio_mmio_config_ops; + vm_dev->pdev = pdev; + INIT_LIST_HEAD(&vm_dev->virtqueues); + spin_lock_init(&vm_dev->lock); + + vm_dev->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(vm_dev->base)) { + rc = PTR_ERR(vm_dev->base); + goto free_vm_dev; + } + + /* Check magic value */ + magic = readl(vm_dev->base + VIRTIO_MMIO_MAGIC_VALUE); + if (magic != ('v' | 'i' << 8 | 'r' << 16 | 't' << 24)) { + dev_warn(&pdev->dev, "Wrong magic value 0x%08lx!\n", magic); + rc = -ENODEV; + goto free_vm_dev; + } + + /* Check device version */ + vm_dev->version = readl(vm_dev->base + VIRTIO_MMIO_VERSION); + if (vm_dev->version < 1 || vm_dev->version > 2) { + dev_err(&pdev->dev, "Version %ld not supported!\n", + vm_dev->version); + rc = -ENXIO; + goto free_vm_dev; + } + + vm_dev->vdev.id.device = readl(vm_dev->base + VIRTIO_MMIO_DEVICE_ID); + if (vm_dev->vdev.id.device == 0) { + /* + * virtio-mmio device with an ID 0 is a (dummy) placeholder + * with no function. End probing now with no error reported. + */ + rc = -ENODEV; + goto free_vm_dev; + } + vm_dev->vdev.id.vendor = readl(vm_dev->base + VIRTIO_MMIO_VENDOR_ID); + + if (vm_dev->version == 1) { + writel(PAGE_SIZE, vm_dev->base + VIRTIO_MMIO_GUEST_PAGE_SIZE); + + rc = dma_set_mask(&pdev->dev, DMA_BIT_MASK(64)); + /* + * In the legacy case, ensure our coherently-allocated virtio + * ring will be at an address expressable as a 32-bit PFN. + */ + if (!rc) + dma_set_coherent_mask(&pdev->dev, + DMA_BIT_MASK(32 + PAGE_SHIFT)); + } else { + rc = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64)); + } + if (rc) + rc = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32)); + if (rc) + dev_warn(&pdev->dev, "Failed to enable 64-bit or 32-bit DMA. Trying to continue, but this might not work.\n"); + + platform_set_drvdata(pdev, vm_dev); + + rc = register_virtio_device(&vm_dev->vdev); + if (rc) + put_device(&vm_dev->vdev.dev); + + return rc; + +free_vm_dev: + kfree(vm_dev); + return rc; +} + +static int virtio_mmio_remove(struct platform_device *pdev) +{ + struct virtio_mmio_device *vm_dev = platform_get_drvdata(pdev); + unregister_virtio_device(&vm_dev->vdev); + + return 0; +} + + + +/* Devices list parameter */ + +#if defined(CONFIG_VIRTIO_MMIO_CMDLINE_DEVICES) + +static struct device vm_cmdline_parent = { + .init_name = "virtio-mmio-cmdline", +}; + +static int vm_cmdline_parent_registered; +static int vm_cmdline_id; + +static int vm_cmdline_set(const char *device, + const struct kernel_param *kp) +{ + int err; + struct resource resources[2] = {}; + char *str; + long long int base, size; + unsigned int irq; + int processed, consumed = 0; + struct platform_device *pdev; + + /* Consume "size" part of the command line parameter */ + size = memparse(device, &str); + + /* Get "@<base>:<irq>[:<id>]" chunks */ + processed = sscanf(str, "@%lli:%u%n:%d%n", + &base, &irq, &consumed, + &vm_cmdline_id, &consumed); + + /* + * sscanf() must process at least 2 chunks; also there + * must be no extra characters after the last chunk, so + * str[consumed] must be '\0' + */ + if (processed < 2 || str[consumed] || irq == 0) + return -EINVAL; + + resources[0].flags = IORESOURCE_MEM; + resources[0].start = base; + resources[0].end = base + size - 1; + + resources[1].flags = IORESOURCE_IRQ; + resources[1].start = resources[1].end = irq; + + if (!vm_cmdline_parent_registered) { + err = device_register(&vm_cmdline_parent); + if (err) { + put_device(&vm_cmdline_parent); + pr_err("Failed to register parent device!\n"); + return err; + } + vm_cmdline_parent_registered = 1; + } + + pr_info("Registering device virtio-mmio.%d at 0x%llx-0x%llx, IRQ %d.\n", + vm_cmdline_id, + (unsigned long long)resources[0].start, + (unsigned long long)resources[0].end, + (int)resources[1].start); + + pdev = platform_device_register_resndata(&vm_cmdline_parent, + "virtio-mmio", vm_cmdline_id++, + resources, ARRAY_SIZE(resources), NULL, 0); + + return PTR_ERR_OR_ZERO(pdev); +} + +static int vm_cmdline_get_device(struct device *dev, void *data) +{ + char *buffer = data; + unsigned int len = strlen(buffer); + struct platform_device *pdev = to_platform_device(dev); + + snprintf(buffer + len, PAGE_SIZE - len, "0x%llx@0x%llx:%llu:%d\n", + pdev->resource[0].end - pdev->resource[0].start + 1ULL, + (unsigned long long)pdev->resource[0].start, + (unsigned long long)pdev->resource[1].start, + pdev->id); + return 0; +} + +static int vm_cmdline_get(char *buffer, const struct kernel_param *kp) +{ + buffer[0] = '\0'; + device_for_each_child(&vm_cmdline_parent, buffer, + vm_cmdline_get_device); + return strlen(buffer) + 1; +} + +static const struct kernel_param_ops vm_cmdline_param_ops = { + .set = vm_cmdline_set, + .get = vm_cmdline_get, +}; + +device_param_cb(device, &vm_cmdline_param_ops, NULL, S_IRUSR); + +static int vm_unregister_cmdline_device(struct device *dev, + void *data) +{ + platform_device_unregister(to_platform_device(dev)); + + return 0; +} + +static void vm_unregister_cmdline_devices(void) +{ + if (vm_cmdline_parent_registered) { + device_for_each_child(&vm_cmdline_parent, NULL, + vm_unregister_cmdline_device); + device_unregister(&vm_cmdline_parent); + vm_cmdline_parent_registered = 0; + } +} + +#else + +static void vm_unregister_cmdline_devices(void) +{ +} + +#endif + +/* Platform driver */ + +static const struct of_device_id virtio_mmio_match[] = { + { .compatible = "virtio,mmio", }, + {}, +}; +MODULE_DEVICE_TABLE(of, virtio_mmio_match); + +#ifdef CONFIG_ACPI +static const struct acpi_device_id virtio_mmio_acpi_match[] = { + { "LNRO0005", }, + { } +}; +MODULE_DEVICE_TABLE(acpi, virtio_mmio_acpi_match); +#endif + +static struct platform_driver virtio_mmio_driver = { + .probe = virtio_mmio_probe, + .remove = virtio_mmio_remove, + .driver = { + .name = "virtio-mmio", + .of_match_table = virtio_mmio_match, + .acpi_match_table = ACPI_PTR(virtio_mmio_acpi_match), +#ifdef CONFIG_PM_SLEEP + .pm = &virtio_mmio_pm_ops, +#endif + }, +}; + +static int __init virtio_mmio_init(void) +{ + return platform_driver_register(&virtio_mmio_driver); +} + +static void __exit virtio_mmio_exit(void) +{ + platform_driver_unregister(&virtio_mmio_driver); + vm_unregister_cmdline_devices(); +} + +module_init(virtio_mmio_init); +module_exit(virtio_mmio_exit); + +MODULE_AUTHOR("Pawel Moll <pawel.moll@arm.com>"); +MODULE_DESCRIPTION("Platform bus driver for memory mapped virtio devices"); +MODULE_LICENSE("GPL"); |