xref: /dpdk/drivers/net/virtio/virtio_pci.c (revision c52afa68d763c58facfbf5a80f452d5cac077125)

/*-
 *   BSD LICENSE
 *
 *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
 *   All rights reserved.
 *
 *   Redistribution and use in source and binary forms, with or without
 *   modification, are permitted provided that the following conditions
 *   are met:
 *
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in
 *       the documentation and/or other materials provided with the
 *       distribution.
 *     * Neither the name of Intel Corporation nor the names of its
 *       contributors may be used to endorse or promote products derived
 *       from this software without specific prior written permission.
 *
 *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
#include <stdint.h>

#ifdef RTE_EXEC_ENV_LINUXAPP
 #include <dirent.h>
 #include <fcntl.h>
#endif

#include "virtio_pci.h"
#include "virtio_logs.h"
#include "virtqueue.h"

static void
legacy_read_dev_config(struct virtio_hw *hw, size_t offset,
		       void *dst, int length)
{
	uint64_t off;
	uint8_t *d;
	int size;

	off = VIRTIO_PCI_CONFIG(hw) + offset;
	for (d = dst; length > 0; d += size, off += size, length -= size) {
		if (length >= 4) {
			size = 4;
			*(uint32_t *)d = VIRTIO_READ_REG_4(hw, off);
		} else if (length >= 2) {
			size = 2;
			*(uint16_t *)d = VIRTIO_READ_REG_2(hw, off);
		} else {
			size = 1;
			*d = VIRTIO_READ_REG_1(hw, off);
		}
	}
}

static void
legacy_write_dev_config(struct virtio_hw *hw, size_t offset,
			const void *src, int length)
{
	uint64_t off;
	const uint8_t *s;
	int size;

	off = VIRTIO_PCI_CONFIG(hw) + offset;
	for (s = src; length > 0; s += size, off += size, length -= size) {
		if (length >= 4) {
			size = 4;
			VIRTIO_WRITE_REG_4(hw, off, *(const uint32_t *)s);
		} else if (length >= 2) {
			size = 2;
			VIRTIO_WRITE_REG_2(hw, off, *(const uint16_t *)s);
		} else {
			size = 1;
			VIRTIO_WRITE_REG_1(hw, off, *s);
		}
	}
}

static uint32_t
legacy_get_features(struct virtio_hw *hw)
{
	return VIRTIO_READ_REG_4(hw, VIRTIO_PCI_HOST_FEATURES);
}

static void
legacy_set_features(struct virtio_hw *hw, uint32_t features)
{
	VIRTIO_WRITE_REG_4(hw, VIRTIO_PCI_GUEST_FEATURES, features);
}

static uint8_t
legacy_get_status(struct virtio_hw *hw)
{
	return VIRTIO_READ_REG_1(hw, VIRTIO_PCI_STATUS);
}

static void
legacy_set_status(struct virtio_hw *hw, uint8_t status)
{
	VIRTIO_WRITE_REG_1(hw, VIRTIO_PCI_STATUS, status);
}

static void
legacy_reset(struct virtio_hw *hw)
{
	legacy_set_status(hw, VIRTIO_CONFIG_STATUS_RESET);
}

static uint8_t
legacy_get_isr(struct virtio_hw *hw)
{
	return VIRTIO_READ_REG_1(hw, VIRTIO_PCI_ISR);
}

/* Enable one vector (0) for Link State Intrerrupt */
static uint16_t
legacy_set_config_irq(struct virtio_hw *hw, uint16_t vec)
{
	VIRTIO_WRITE_REG_2(hw, VIRTIO_MSI_CONFIG_VECTOR, vec);
	return VIRTIO_READ_REG_2(hw, VIRTIO_MSI_CONFIG_VECTOR);
}

static uint16_t
legacy_get_queue_num(struct virtio_hw *hw, uint16_t queue_id)
{
	VIRTIO_WRITE_REG_2(hw, VIRTIO_PCI_QUEUE_SEL, queue_id);
	return VIRTIO_READ_REG_2(hw, VIRTIO_PCI_QUEUE_NUM);
}

static void
legacy_setup_queue(struct virtio_hw *hw, struct virtqueue *vq)
{
	VIRTIO_WRITE_REG_2(hw, VIRTIO_PCI_QUEUE_SEL, vq->vq_queue_index);

	VIRTIO_WRITE_REG_4(hw, VIRTIO_PCI_QUEUE_PFN,
		vq->mz->phys_addr >> VIRTIO_PCI_QUEUE_ADDR_SHIFT);
}

static void
legacy_del_queue(struct virtio_hw *hw, struct virtqueue *vq)
{
	VIRTIO_WRITE_REG_2(hw, VIRTIO_PCI_QUEUE_SEL, vq->vq_queue_index);

	VIRTIO_WRITE_REG_4(hw, VIRTIO_PCI_QUEUE_PFN, 0);
}

static void
legacy_notify_queue(struct virtio_hw *hw, struct virtqueue *vq)
{
	VIRTIO_WRITE_REG_2(hw, VIRTIO_PCI_QUEUE_NOTIFY, vq->vq_queue_index);
}

#ifdef RTE_EXEC_ENV_LINUXAPP
static int
parse_sysfs_value(const char *filename, unsigned long *val)
{
	FILE *f;
	char buf[BUFSIZ];
	char *end = NULL;

	f = fopen(filename, "r");
	if (f == NULL) {
		PMD_INIT_LOG(ERR, "%s(): cannot open sysfs value %s",
			     __func__, filename);
		return -1;
	}

	if (fgets(buf, sizeof(buf), f) == NULL) {
		PMD_INIT_LOG(ERR, "%s(): cannot read sysfs value %s",
			     __func__, filename);
		fclose(f);
		return -1;
	}
	*val = strtoul(buf, &end, 0);
	if ((buf[0] == '\0') || (end == NULL) || (*end != '\n')) {
		PMD_INIT_LOG(ERR, "%s(): cannot parse sysfs value %s",
			     __func__, filename);
		fclose(f);
		return -1;
	}
	fclose(f);
	return 0;
}

static int
get_uio_dev(struct rte_pci_addr *loc, char *buf, unsigned int buflen,
			unsigned int *uio_num)
{
	struct dirent *e;
	DIR *dir;
	char dirname[PATH_MAX];

	/*
	 * depending on kernel version, uio can be located in uio/uioX
	 * or uio:uioX
	 */
	snprintf(dirname, sizeof(dirname),
		     SYSFS_PCI_DEVICES "/" PCI_PRI_FMT "/uio",
		     loc->domain, loc->bus, loc->devid, loc->function);
	dir = opendir(dirname);
	if (dir == NULL) {
		/* retry with the parent directory */
		snprintf(dirname, sizeof(dirname),
			     SYSFS_PCI_DEVICES "/" PCI_PRI_FMT,
			     loc->domain, loc->bus, loc->devid, loc->function);
		dir = opendir(dirname);

		if (dir == NULL) {
			PMD_INIT_LOG(ERR, "Cannot opendir %s", dirname);
			return -1;
		}
	}

	/* take the first file starting with "uio" */
	while ((e = readdir(dir)) != NULL) {
		/* format could be uio%d ...*/
		int shortprefix_len = sizeof("uio") - 1;
		/* ... or uio:uio%d */
		int longprefix_len = sizeof("uio:uio") - 1;
		char *endptr;

		if (strncmp(e->d_name, "uio", 3) != 0)
			continue;

		/* first try uio%d */
		errno = 0;
		*uio_num = strtoull(e->d_name + shortprefix_len, &endptr, 10);
		if (errno == 0 && endptr != (e->d_name + shortprefix_len)) {
			snprintf(buf, buflen, "%s/uio%u", dirname, *uio_num);
			break;
		}

		/* then try uio:uio%d */
		errno = 0;
		*uio_num = strtoull(e->d_name + longprefix_len, &endptr, 10);
		if (errno == 0 && endptr != (e->d_name + longprefix_len)) {
			snprintf(buf, buflen, "%s/uio:uio%u", dirname,
				     *uio_num);
			break;
		}
	}
	closedir(dir);

	/* No uio resource found */
	if (e == NULL) {
		PMD_INIT_LOG(ERR, "Could not find uio resource");
		return -1;
	}

	return 0;
}

static int
legacy_virtio_has_msix(const struct rte_pci_addr *loc)
{
	DIR *d;
	char dirname[PATH_MAX];

	snprintf(dirname, sizeof(dirname),
		     SYSFS_PCI_DEVICES "/" PCI_PRI_FMT "/msi_irqs",
		     loc->domain, loc->bus, loc->devid, loc->function);

	d = opendir(dirname);
	if (d)
		closedir(d);

	return (d != NULL);
}

/* Extract I/O port numbers from sysfs */
static int
virtio_resource_init_by_uio(struct rte_pci_device *pci_dev)
{
	char dirname[PATH_MAX];
	char filename[PATH_MAX];
	unsigned long start, size;
	unsigned int uio_num;

	if (get_uio_dev(&pci_dev->addr, dirname, sizeof(dirname), &uio_num) < 0)
		return -1;

	/* get portio size */
	snprintf(filename, sizeof(filename),
		     "%s/portio/port0/size", dirname);
	if (parse_sysfs_value(filename, &size) < 0) {
		PMD_INIT_LOG(ERR, "%s(): cannot parse size",
			     __func__);
		return -1;
	}

	/* get portio start */
	snprintf(filename, sizeof(filename),
		 "%s/portio/port0/start", dirname);
	if (parse_sysfs_value(filename, &start) < 0) {
		PMD_INIT_LOG(ERR, "%s(): cannot parse portio start",
			     __func__);
		return -1;
	}
	pci_dev->mem_resource[0].addr = (void *)(uintptr_t)start;
	pci_dev->mem_resource[0].len =  (uint64_t)size;
	PMD_INIT_LOG(DEBUG,
		     "PCI Port IO found start=0x%lx with size=0x%lx",
		     start, size);

	/* save fd */
	memset(dirname, 0, sizeof(dirname));
	snprintf(dirname, sizeof(dirname), "/dev/uio%u", uio_num);
	pci_dev->intr_handle.fd = open(dirname, O_RDWR);
	if (pci_dev->intr_handle.fd < 0) {
		PMD_INIT_LOG(ERR, "Cannot open %s: %s\n",
			dirname, strerror(errno));
		return -1;
	}

	pci_dev->intr_handle.type = RTE_INTR_HANDLE_UIO;
	pci_dev->driver->drv_flags |= RTE_PCI_DRV_INTR_LSC;

	return 0;
}

/* Extract port I/O numbers from proc/ioports */
static int
virtio_resource_init_by_ioports(struct rte_pci_device *pci_dev)
{
	uint16_t start, end;
	int size;
	FILE *fp;
	char *line = NULL;
	char pci_id[16];
	int found = 0;
	size_t linesz;

	snprintf(pci_id, sizeof(pci_id), PCI_PRI_FMT,
		 pci_dev->addr.domain,
		 pci_dev->addr.bus,
		 pci_dev->addr.devid,
		 pci_dev->addr.function);

	fp = fopen("/proc/ioports", "r");
	if (fp == NULL) {
		PMD_INIT_LOG(ERR, "%s(): can't open ioports", __func__);
		return -1;
	}

	while (getdelim(&line, &linesz, '\n', fp) > 0) {
		char *ptr = line;
		char *left;
		int n;

		n = strcspn(ptr, ":");
		ptr[n] = 0;
		left = &ptr[n + 1];

		while (*left && isspace(*left))
			left++;

		if (!strncmp(left, pci_id, strlen(pci_id))) {
			found = 1;

			while (*ptr && isspace(*ptr))
				ptr++;

			sscanf(ptr, "%04hx-%04hx", &start, &end);
			size = end - start + 1;

			break;
		}
	}

	free(line);
	fclose(fp);

	if (!found)
		return -1;

	pci_dev->mem_resource[0].addr = (void *)(uintptr_t)(uint32_t)start;
	pci_dev->mem_resource[0].len =  (uint64_t)size;
	PMD_INIT_LOG(DEBUG,
		"PCI Port IO found start=0x%x with size=0x%x",
		start, size);

	/* can't support lsc interrupt without uio */
	pci_dev->driver->drv_flags &= ~RTE_PCI_DRV_INTR_LSC;

	return 0;
}

/* Extract I/O port numbers from sysfs */
static int
legacy_virtio_resource_init(struct rte_pci_device *pci_dev)
{
	if (virtio_resource_init_by_uio(pci_dev) == 0)
		return 0;
	else
		return virtio_resource_init_by_ioports(pci_dev);
}

#else
static int
legayc_virtio_has_msix(const struct rte_pci_addr *loc __rte_unused)
{
	/* nic_uio does not enable interrupts, return 0 (false). */
	return 0;
}

static int
legacy_virtio_resource_init(struct rte_pci_device *pci_dev __rte_unused)
{
	/* no setup required */
	return 0;
}
#endif

static const struct virtio_pci_ops legacy_ops = {
	.read_dev_cfg	= legacy_read_dev_config,
	.write_dev_cfg	= legacy_write_dev_config,
	.reset		= legacy_reset,
	.get_status	= legacy_get_status,
	.set_status	= legacy_set_status,
	.get_features	= legacy_get_features,
	.set_features	= legacy_set_features,
	.get_isr	= legacy_get_isr,
	.set_config_irq	= legacy_set_config_irq,
	.get_queue_num	= legacy_get_queue_num,
	.setup_queue	= legacy_setup_queue,
	.del_queue	= legacy_del_queue,
	.notify_queue	= legacy_notify_queue,
};


void
vtpci_read_dev_config(struct virtio_hw *hw, size_t offset,
		      void *dst, int length)
{
	hw->vtpci_ops->read_dev_cfg(hw, offset, dst, length);
}

void
vtpci_write_dev_config(struct virtio_hw *hw, size_t offset,
		       const void *src, int length)
{
	hw->vtpci_ops->write_dev_cfg(hw, offset, src, length);
}

uint32_t
vtpci_negotiate_features(struct virtio_hw *hw, uint32_t host_features)
{
	uint32_t features;

	/*
	 * Limit negotiated features to what the driver, virtqueue, and
	 * host all support.
	 */
	features = host_features & hw->guest_features;
	hw->vtpci_ops->set_features(hw, features);

	return features;
}

void
vtpci_reset(struct virtio_hw *hw)
{
	hw->vtpci_ops->set_status(hw, VIRTIO_CONFIG_STATUS_RESET);
	/* flush status write */
	hw->vtpci_ops->get_status(hw);
}

void
vtpci_reinit_complete(struct virtio_hw *hw)
{
	vtpci_set_status(hw, VIRTIO_CONFIG_STATUS_DRIVER_OK);
}

void
vtpci_set_status(struct virtio_hw *hw, uint8_t status)
{
	if (status != VIRTIO_CONFIG_STATUS_RESET)
		status |= hw->vtpci_ops->get_status(hw);

	hw->vtpci_ops->set_status(hw, status);
}

uint8_t
vtpci_isr(struct virtio_hw *hw)
{
	return hw->vtpci_ops->get_isr(hw);
}


/* Enable one vector (0) for Link State Intrerrupt */
uint16_t
vtpci_irq_config(struct virtio_hw *hw, uint16_t vec)
{
	return hw->vtpci_ops->set_config_irq(hw, vec);
}

int
vtpci_init(struct rte_pci_device *dev, struct virtio_hw *hw)
{
	hw->vtpci_ops = &legacy_ops;

	if (legacy_virtio_resource_init(dev) < 0)
		return -1;
	hw->use_msix = legacy_virtio_has_msix(&dev->addr);
	hw->io_base  = (uint32_t)(uintptr_t)dev->mem_resource[0].addr;

	return 0;
}