// 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 <[email protected]>");
MODULE_LICENSE("GPL");
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