/*
* 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.
*
*
*
- * 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.
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;
- /* TODO: Features > 32 bits */
- writel(0, vm_dev->base + VIRTIO_MMIO_HOST_FEATURES_SEL);
+ writel(0, vm_dev->base + VIRTIO_MMIO_DEVICE_FEATURES_SEL);
+ features |= readl(vm_dev->base + VIRTIO_MMIO_DEVICE_FEATURES);
- return readl(vm_dev->base + VIRTIO_MMIO_HOST_FEATURES);
+ return features;
}
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(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_GUEST_FEATURES_SEL);
- writel(vdev->features, vm_dev->base + VIRTIO_MMIO_GUEST_FEATURES);
+ writel(0, vm_dev->base + VIRTIO_MMIO_DRIVER_FEATURES_SEL);
+ writel((u32)vdev->features,
+ vm_dev->base + VIRTIO_MMIO_DRIVER_FEATURES);
return 0;
}
/* 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);
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;
}
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);
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;
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);
/* 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);
/* 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
/* 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
/* 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