diff --git a/drivers/virtio/virtio_mmio.c b/drivers/virtio/virtio_mmio.c index 00d115b22bd8..cad569890908 100644 --- a/drivers/virtio/virtio_mmio.c +++ b/drivers/virtio/virtio_mmio.c @@ -1,7 +1,7 @@ /* * Virtio memory mapped device driver * - * Copyright 2011, ARM Ltd. + * Copyright 2011-2014, ARM Ltd. * * This module allows virtio devices to be used over a virtual, memory mapped * platform device. @@ -50,36 +50,6 @@ * * * - * Registers layout (all 32-bit wide): - * - * offset d. name description - * ------ -- ---------------- ----------------- - * - * 0x000 R MagicValue Magic value "virt" - * 0x004 R Version Device version (current max. 1) - * 0x008 R DeviceID Virtio device ID - * 0x00c R VendorID Virtio vendor ID - * - * 0x010 R HostFeatures Features supported by the host - * 0x014 W HostFeaturesSel Set of host features to access via HostFeatures - * - * 0x020 W GuestFeatures Features activated by the guest - * 0x024 W GuestFeaturesSel Set of activated features to set via GuestFeatures - * 0x028 W GuestPageSize Size of guest's memory page in bytes - * - * 0x030 W QueueSel Queue selector - * 0x034 R QueueNumMax Maximum size of the currently selected queue - * 0x038 W QueueNum Queue size for the currently selected queue - * 0x03c W QueueAlign Used Ring alignment for the current queue - * 0x040 RW QueuePFN PFN for the currently selected queue - * - * 0x050 W QueueNotify Queue notifier - * 0x060 R InterruptStatus Interrupt status register - * 0x064 W InterruptACK Interrupt acknowledge register - * 0x070 RW Status Device status register - * - * 0x100+ RW Device-specific configuration space - * * Based on Virtio PCI driver by Anthony Liguori, copyright IBM Corp. 2007 * * This work is licensed under the terms of the GNU GPL, version 2 or later. @@ -145,11 +115,16 @@ struct virtio_mmio_vq_info { static u64 vm_get_features(struct virtio_device *vdev) { struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev); + u64 features; - /* TODO: Features > 32 bits */ - writel(0, vm_dev->base + VIRTIO_MMIO_HOST_FEATURES_SEL); + writel(1, vm_dev->base + VIRTIO_MMIO_DEVICE_FEATURES_SEL); + features = readl(vm_dev->base + VIRTIO_MMIO_DEVICE_FEATURES); + features <<= 32; - return readl(vm_dev->base + VIRTIO_MMIO_HOST_FEATURES); + 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) @@ -159,11 +134,20 @@ static int vm_finalize_features(struct virtio_device *vdev) /* Give virtio_ring a chance to accept features. */ vring_transport_features(vdev); - /* Make sure we don't have any features > 32 bits! */ - BUG_ON((u32)vdev->features != vdev->features); + /* 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(0, vm_dev->base + VIRTIO_MMIO_GUEST_FEATURES_SEL); - writel(vdev->features, vm_dev->base + VIRTIO_MMIO_GUEST_FEATURES); + 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; } @@ -275,7 +259,12 @@ static void vm_del_vq(struct virtqueue *vq) /* Select and deactivate the queue */ writel(index, vm_dev->base + VIRTIO_MMIO_QUEUE_SEL); - writel(0, vm_dev->base + VIRTIO_MMIO_QUEUE_PFN); + 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)); + } size = PAGE_ALIGN(vring_size(info->num, VIRTIO_MMIO_VRING_ALIGN)); free_pages_exact(info->queue, size); @@ -312,7 +301,8 @@ static struct virtqueue *vm_setup_vq(struct virtio_device *vdev, unsigned index, writel(index, vm_dev->base + VIRTIO_MMIO_QUEUE_SEL); /* Queue shouldn't already be set up. */ - if (readl(vm_dev->base + VIRTIO_MMIO_QUEUE_PFN)) { + if (readl(vm_dev->base + (vm_dev->version == 1 ? + VIRTIO_MMIO_QUEUE_PFN : VIRTIO_MMIO_QUEUE_READY))) { err = -ENOENT; goto error_available; } @@ -356,13 +346,6 @@ static struct virtqueue *vm_setup_vq(struct virtio_device *vdev, unsigned index, info->num /= 2; } - /* Activate the queue */ - writel(info->num, vm_dev->base + VIRTIO_MMIO_QUEUE_NUM); - writel(VIRTIO_MMIO_VRING_ALIGN, - vm_dev->base + VIRTIO_MMIO_QUEUE_ALIGN); - writel(virt_to_phys(info->queue) >> PAGE_SHIFT, - vm_dev->base + VIRTIO_MMIO_QUEUE_PFN); - /* Create the vring */ vq = vring_new_virtqueue(index, info->num, VIRTIO_MMIO_VRING_ALIGN, vdev, true, info->queue, vm_notify, callback, name); @@ -371,6 +354,33 @@ static struct virtqueue *vm_setup_vq(struct virtio_device *vdev, unsigned index, goto error_new_virtqueue; } + /* Activate the queue */ + writel(info->num, vm_dev->base + VIRTIO_MMIO_QUEUE_NUM); + if (vm_dev->version == 1) { + writel(PAGE_SIZE, vm_dev->base + VIRTIO_MMIO_QUEUE_ALIGN); + writel(virt_to_phys(info->queue) >> PAGE_SHIFT, + vm_dev->base + VIRTIO_MMIO_QUEUE_PFN); + } else { + u64 addr; + + addr = virt_to_phys(info->queue); + writel((u32)addr, vm_dev->base + VIRTIO_MMIO_QUEUE_DESC_LOW); + writel((u32)(addr >> 32), + vm_dev->base + VIRTIO_MMIO_QUEUE_DESC_HIGH); + + addr = virt_to_phys(virtqueue_get_avail(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 = virt_to_phys(virtqueue_get_used(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; @@ -381,7 +391,12 @@ static struct virtqueue *vm_setup_vq(struct virtio_device *vdev, unsigned index, return vq; error_new_virtqueue: - writel(0, vm_dev->base + VIRTIO_MMIO_QUEUE_PFN); + 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)); + } free_pages_exact(info->queue, size); error_alloc_pages: kfree(info); @@ -476,16 +491,32 @@ static int virtio_mmio_probe(struct platform_device *pdev) /* Check device version */ vm_dev->version = readl(vm_dev->base + VIRTIO_MMIO_VERSION); - if (vm_dev->version != 1) { + if (vm_dev->version < 1 || vm_dev->version > 2) { dev_err(&pdev->dev, "Version %ld not supported!\n", vm_dev->version); return -ENXIO; } 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. + */ + return -ENODEV; + } vm_dev->vdev.id.vendor = readl(vm_dev->base + VIRTIO_MMIO_VENDOR_ID); - writel(PAGE_SIZE, vm_dev->base + VIRTIO_MMIO_GUEST_PAGE_SIZE); + /* Reject legacy-only IDs for version 2 devices */ + if (vm_dev->version == 2 && + virtio_device_is_legacy_only(vm_dev->vdev.id)) { + dev_err(&pdev->dev, "Version 2 not supported for devices %u!\n", + vm_dev->vdev.id.device); + return -ENODEV; + } + + if (vm_dev->version == 1) + writel(PAGE_SIZE, vm_dev->base + VIRTIO_MMIO_GUEST_PAGE_SIZE); platform_set_drvdata(pdev, vm_dev); diff --git a/include/linux/virtio_mmio.h b/include/linux/virtio_mmio.h index 5c7b6f0daef8..c4b09689ab64 100644 --- a/include/linux/virtio_mmio.h +++ b/include/linux/virtio_mmio.h @@ -51,23 +51,29 @@ /* Virtio vendor ID - Read Only */ #define VIRTIO_MMIO_VENDOR_ID 0x00c -/* Bitmask of the features supported by the host +/* Bitmask of the features supported by the device (host) * (32 bits per set) - Read Only */ -#define VIRTIO_MMIO_HOST_FEATURES 0x010 +#define VIRTIO_MMIO_DEVICE_FEATURES 0x010 -/* Host features set selector - Write Only */ -#define VIRTIO_MMIO_HOST_FEATURES_SEL 0x014 +/* Device (host) features set selector - Write Only */ +#define VIRTIO_MMIO_DEVICE_FEATURES_SEL 0x014 -/* Bitmask of features activated by the guest +/* Bitmask of features activated by the driver (guest) * (32 bits per set) - Write Only */ -#define VIRTIO_MMIO_GUEST_FEATURES 0x020 +#define VIRTIO_MMIO_DRIVER_FEATURES 0x020 /* Activated features set selector - Write Only */ -#define VIRTIO_MMIO_GUEST_FEATURES_SEL 0x024 +#define VIRTIO_MMIO_DRIVER_FEATURES_SEL 0x024 + + +#ifndef VIRTIO_MMIO_NO_LEGACY /* LEGACY DEVICES ONLY! */ /* Guest's memory page size in bytes - Write Only */ #define VIRTIO_MMIO_GUEST_PAGE_SIZE 0x028 +#endif + + /* Queue selector - Write Only */ #define VIRTIO_MMIO_QUEUE_SEL 0x030 @@ -77,12 +83,21 @@ /* Queue size for the currently selected queue - Write Only */ #define VIRTIO_MMIO_QUEUE_NUM 0x038 + +#ifndef VIRTIO_MMIO_NO_LEGACY /* LEGACY DEVICES ONLY! */ + /* Used Ring alignment for the currently selected queue - Write Only */ #define VIRTIO_MMIO_QUEUE_ALIGN 0x03c /* Guest's PFN for the currently selected queue - Read Write */ #define VIRTIO_MMIO_QUEUE_PFN 0x040 +#endif + + +/* Ready bit for the currently selected queue - Read Write */ +#define VIRTIO_MMIO_QUEUE_READY 0x044 + /* Queue notifier - Write Only */ #define VIRTIO_MMIO_QUEUE_NOTIFY 0x050 @@ -95,6 +110,21 @@ /* Device status register - Read Write */ #define VIRTIO_MMIO_STATUS 0x070 +/* Selected queue's Descriptor Table address, 64 bits in two halves */ +#define VIRTIO_MMIO_QUEUE_DESC_LOW 0x080 +#define VIRTIO_MMIO_QUEUE_DESC_HIGH 0x084 + +/* Selected queue's Available Ring address, 64 bits in two halves */ +#define VIRTIO_MMIO_QUEUE_AVAIL_LOW 0x090 +#define VIRTIO_MMIO_QUEUE_AVAIL_HIGH 0x094 + +/* Selected queue's Used Ring address, 64 bits in two halves */ +#define VIRTIO_MMIO_QUEUE_USED_LOW 0x0a0 +#define VIRTIO_MMIO_QUEUE_USED_HIGH 0x0a4 + +/* Configuration atomicity value */ +#define VIRTIO_MMIO_CONFIG_GENERATION 0x0fc + /* The config space is defined by each driver as * the per-driver configuration space - Read Write */ #define VIRTIO_MMIO_CONFIG 0x100