diff options
Diffstat (limited to 'drivers/virtio/virtio_pci_legacy_dev.c')
| -rw-r--r-- | drivers/virtio/virtio_pci_legacy_dev.c | 222 |
1 files changed, 222 insertions, 0 deletions
diff --git a/drivers/virtio/virtio_pci_legacy_dev.c b/drivers/virtio/virtio_pci_legacy_dev.c new file mode 100644 index 000000000..677d1f68b --- /dev/null +++ b/drivers/virtio/virtio_pci_legacy_dev.c @@ -0,0 +1,222 @@ +// SPDX-License-Identifier: GPL-2.0-or-later + +#include "linux/virtio_pci.h" +#include <linux/virtio_pci_legacy.h> +#include <linux/module.h> +#include <linux/pci.h> + + +/* + * vp_legacy_probe: probe the legacy virtio pci device, note that the + * caller is required to enable PCI device before calling this function. + * @ldev: the legacy virtio-pci device + * + * Return 0 on succeed otherwise fail + */ +int vp_legacy_probe(struct virtio_pci_legacy_device *ldev) +{ + struct pci_dev *pci_dev = ldev->pci_dev; + int rc; + + /* We only own devices >= 0x1000 and <= 0x103f: leave the rest. */ + if (pci_dev->device < 0x1000 || pci_dev->device > 0x103f) + return -ENODEV; + + if (pci_dev->revision != VIRTIO_PCI_ABI_VERSION) + return -ENODEV; + + rc = dma_set_mask(&pci_dev->dev, DMA_BIT_MASK(64)); + if (rc) { + rc = dma_set_mask_and_coherent(&pci_dev->dev, DMA_BIT_MASK(32)); + } else { + /* + * The virtio ring base address is expressed as a 32-bit PFN, + * with a page size of 1 << VIRTIO_PCI_QUEUE_ADDR_SHIFT. + */ + dma_set_coherent_mask(&pci_dev->dev, + DMA_BIT_MASK(32 + VIRTIO_PCI_QUEUE_ADDR_SHIFT)); + } + + if (rc) + dev_warn(&pci_dev->dev, "Failed to enable 64-bit or 32-bit DMA. Trying to continue, but this might not work.\n"); + + rc = pci_request_region(pci_dev, 0, "virtio-pci-legacy"); + if (rc) + return rc; + + ldev->ioaddr = pci_iomap(pci_dev, 0, 0); + if (!ldev->ioaddr) { + rc = -EIO; + goto err_iomap; + } + + ldev->isr = ldev->ioaddr + VIRTIO_PCI_ISR; + + ldev->id.vendor = pci_dev->subsystem_vendor; + ldev->id.device = pci_dev->subsystem_device; + + return 0; +err_iomap: + pci_release_region(pci_dev, 0); + return rc; +} +EXPORT_SYMBOL_GPL(vp_legacy_probe); + +/* + * vp_legacy_probe: remove and cleanup the legacy virtio pci device + * @ldev: the legacy virtio-pci device + */ +void vp_legacy_remove(struct virtio_pci_legacy_device *ldev) +{ + struct pci_dev *pci_dev = ldev->pci_dev; + + pci_iounmap(pci_dev, ldev->ioaddr); + pci_release_region(pci_dev, 0); +} +EXPORT_SYMBOL_GPL(vp_legacy_remove); + +/* + * vp_legacy_get_features - get features from device + * @ldev: the legacy virtio-pci device + * + * Returns the features read from the device + */ +u64 vp_legacy_get_features(struct virtio_pci_legacy_device *ldev) +{ + + return ioread32(ldev->ioaddr + VIRTIO_PCI_HOST_FEATURES); +} +EXPORT_SYMBOL_GPL(vp_legacy_get_features); + +/* + * vp_legacy_get_driver_features - get driver features from device + * @ldev: the legacy virtio-pci device + * + * Returns the driver features read from the device + */ +u64 vp_legacy_get_driver_features(struct virtio_pci_legacy_device *ldev) +{ + return ioread32(ldev->ioaddr + VIRTIO_PCI_GUEST_FEATURES); +} +EXPORT_SYMBOL_GPL(vp_legacy_get_driver_features); + +/* + * vp_legacy_set_features - set features to device + * @ldev: the legacy virtio-pci device + * @features: the features set to device + */ +void vp_legacy_set_features(struct virtio_pci_legacy_device *ldev, + u32 features) +{ + iowrite32(features, ldev->ioaddr + VIRTIO_PCI_GUEST_FEATURES); +} +EXPORT_SYMBOL_GPL(vp_legacy_set_features); + +/* + * vp_legacy_get_status - get the device status + * @ldev: the legacy virtio-pci device + * + * Returns the status read from device + */ +u8 vp_legacy_get_status(struct virtio_pci_legacy_device *ldev) +{ + return ioread8(ldev->ioaddr + VIRTIO_PCI_STATUS); +} +EXPORT_SYMBOL_GPL(vp_legacy_get_status); + +/* + * vp_legacy_set_status - set status to device + * @ldev: the legacy virtio-pci device + * @status: the status set to device + */ +void vp_legacy_set_status(struct virtio_pci_legacy_device *ldev, + u8 status) +{ + iowrite8(status, ldev->ioaddr + VIRTIO_PCI_STATUS); +} +EXPORT_SYMBOL_GPL(vp_legacy_set_status); + +/* + * vp_legacy_queue_vector - set the MSIX vector for a specific virtqueue + * @ldev: the legacy virtio-pci device + * @index: queue index + * @vector: the config vector + * + * Returns the config vector read from the device + */ +u16 vp_legacy_queue_vector(struct virtio_pci_legacy_device *ldev, + u16 index, u16 vector) +{ + iowrite16(index, ldev->ioaddr + VIRTIO_PCI_QUEUE_SEL); + iowrite16(vector, ldev->ioaddr + VIRTIO_MSI_QUEUE_VECTOR); + /* Flush the write out to device */ + return ioread16(ldev->ioaddr + VIRTIO_MSI_QUEUE_VECTOR); +} +EXPORT_SYMBOL_GPL(vp_legacy_queue_vector); + +/* + * vp_legacy_config_vector - set the vector for config interrupt + * @ldev: the legacy virtio-pci device + * @vector: the config vector + * + * Returns the config vector read from the device + */ +u16 vp_legacy_config_vector(struct virtio_pci_legacy_device *ldev, + u16 vector) +{ + /* Setup the vector used for configuration events */ + iowrite16(vector, ldev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR); + /* Verify we had enough resources to assign the vector */ + /* Will also flush the write out to device */ + return ioread16(ldev->ioaddr + VIRTIO_MSI_CONFIG_VECTOR); +} +EXPORT_SYMBOL_GPL(vp_legacy_config_vector); + +/* + * vp_legacy_set_queue_address - set the virtqueue address + * @ldev: the legacy virtio-pci device + * @index: the queue index + * @queue_pfn: pfn of the virtqueue + */ +void vp_legacy_set_queue_address(struct virtio_pci_legacy_device *ldev, + u16 index, u32 queue_pfn) +{ + iowrite16(index, ldev->ioaddr + VIRTIO_PCI_QUEUE_SEL); + iowrite32(queue_pfn, ldev->ioaddr + VIRTIO_PCI_QUEUE_PFN); +} +EXPORT_SYMBOL_GPL(vp_legacy_set_queue_address); + +/* + * vp_legacy_get_queue_enable - enable a virtqueue + * @ldev: the legacy virtio-pci device + * @index: the queue index + * + * Returns whether a virtqueue is enabled or not + */ +bool vp_legacy_get_queue_enable(struct virtio_pci_legacy_device *ldev, + u16 index) +{ + iowrite16(index, ldev->ioaddr + VIRTIO_PCI_QUEUE_SEL); + return ioread32(ldev->ioaddr + VIRTIO_PCI_QUEUE_PFN); +} +EXPORT_SYMBOL_GPL(vp_legacy_get_queue_enable); + +/* + * vp_legacy_get_queue_size - get size for a virtqueue + * @ldev: the legacy virtio-pci device + * @index: the queue index + * + * Returns the size of the virtqueue + */ +u16 vp_legacy_get_queue_size(struct virtio_pci_legacy_device *ldev, + u16 index) +{ + iowrite16(index, ldev->ioaddr + VIRTIO_PCI_QUEUE_SEL); + return ioread16(ldev->ioaddr + VIRTIO_PCI_QUEUE_NUM); +} +EXPORT_SYMBOL_GPL(vp_legacy_get_queue_size); + +MODULE_VERSION("0.1"); +MODULE_DESCRIPTION("Legacy Virtio PCI Device"); +MODULE_AUTHOR("Wu Zongyong <wuzongyong@linux.alibaba.com>"); +MODULE_LICENSE("GPL"); |