[RFC 0/2] Intel IFC VF driver for vdpa

[RFC 0/2] Intel IFC VF driver for vdpa

[Zhu Lingshan]

Hi all:
 
This series intends to introduce Intel IFC VF NIC driver for Vhost
Data Plane Acceleration.
 
Here comes two main parts, one is ifcvf_base layer, which handles
hardware operations. The other is ifcvf_main layer handles VF
initialization, configuration and removal, which depends on
and complys to vhost_mdev https://lkml.org/lkml/2019/9/26/15 
 
This is a first RFC try, please help review.
 
Thanks!
BR
Zhu Lingshan


Zhu Lingshan (2):
  vhost: IFC VF hardware operation layer
  vhost: IFC VF vdpa layer

 drivers/vhost/ifcvf/ifcvf_base.c | 390 ++++++++++++++++++++++++++++
 drivers/vhost/ifcvf/ifcvf_base.h | 137 ++++++++++
 drivers/vhost/ifcvf/ifcvf_main.c | 541 +++++++++++++++++++++++++++++++++++++++
 3 files changed, 1068 insertions(+)
 create mode 100644 drivers/vhost/ifcvf/ifcvf_base.c
 create mode 100644 drivers/vhost/ifcvf/ifcvf_base.h
 create mode 100644 drivers/vhost/ifcvf/ifcvf_main.c

-- 
2.16.4

[RFC 1/2] vhost: IFC VF hardware operation layer

[Zhu Lingshan]

This commit introduced ifcvf_base layer, which handles IFC VF NIC
hardware operations and configurations.

Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
---
 drivers/vhost/ifcvf/ifcvf_base.c | 390 +++++++++++++++++++++++++++++++++++++++
 drivers/vhost/ifcvf/ifcvf_base.h | 137 ++++++++++++++
 2 files changed, 527 insertions(+)
 create mode 100644 drivers/vhost/ifcvf/ifcvf_base.c
 create mode 100644 drivers/vhost/ifcvf/ifcvf_base.h

diff --git a/drivers/vhost/ifcvf/ifcvf_base.c b/drivers/vhost/ifcvf/ifcvf_base.c
new file mode 100644
index 000000000000..b85e14c9bdcf
--- /dev/null
+++ b/drivers/vhost/ifcvf/ifcvf_base.c
@@ -0,0 +1,390 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2019 Intel Corporation.
+ */
+
+#include "ifcvf_base.h"
+
+static void *get_cap_addr(struct ifcvf_hw *hw, struct virtio_pci_cap *cap)
+{
+	u8 bar = cap->bar;
+	u32 length = cap->length;
+	u32 offset = cap->offset;
+	struct ifcvf_adapter *ifcvf =
+		container_of(hw, struct ifcvf_adapter, vf);
+
+	if (bar >= IFCVF_PCI_MAX_RESOURCE) {
+		IFC_ERR(ifcvf->dev,
+			"Invalid bar number %u to get capabilities.\n", bar);
+		return NULL;
+	}
+
+	if (offset + length < offset) {
+		IFC_ERR(ifcvf->dev, "offset(%u) + length(%u) overflows\n",
+			offset, length);
+		return NULL;
+	}
+
+	if (offset + length > hw->mem_resource[cap->bar].len) {
+		IFC_ERR(ifcvf->dev,
+			"offset(%u) + len(%u) overflows bar%u to get capabilities.\n",
+			offset, length, bar);
+		return NULL;
+	}
+
+	return hw->mem_resource[bar].addr + offset;
+}
+
+int ifcvf_read_config_range(struct pci_dev *dev,
+			uint32_t *val, int size, int where)
+{
+	int i;
+
+	for (i = 0; i < size; i += 4) {
+		if (pci_read_config_dword(dev, where + i, val + i / 4) < 0)
+			return -1;
+	}
+	return 0;
+}
+
+int ifcvf_init_hw(struct ifcvf_hw *hw, struct pci_dev *dev)
+{
+	int ret;
+	u8 pos;
+	struct virtio_pci_cap cap;
+	u32 i;
+	u16 notify_off;
+
+	ret = pci_read_config_byte(dev, PCI_CAPABILITY_LIST, &pos);
+
+	if (ret < 0) {
+		IFC_ERR(&dev->dev, "failed to read PCI capability list.\n");
+		return -EIO;
+	}
+
+	while (pos) {
+		ret = ifcvf_read_config_range(dev, (u32 *)&cap,
+				sizeof(cap), pos);
+
+		if (ret < 0) {
+			IFC_ERR(&dev->dev, "failed to get PCI capability at %x",
+					pos);
+			break;
+		}
+
+		if (cap.cap_vndr != PCI_CAP_ID_VNDR)
+			goto next;
+
+		IFC_INFO(&dev->dev, "read PCI config:\n"
+					"config type: %u.\n"
+					"PCI bar: %u.\n"
+					"PCI bar offset: %u.\n"
+					"PCI config len: %u.\n",
+					cap.cfg_type, cap.bar,
+					cap.offset, cap.length);
+
+		switch (cap.cfg_type) {
+		case VIRTIO_PCI_CAP_COMMON_CFG:
+			hw->common_cfg = get_cap_addr(hw, &cap);
+			IFC_INFO(&dev->dev, "hw->common_cfg = %p.\n",
+					hw->common_cfg);
+			break;
+		case VIRTIO_PCI_CAP_NOTIFY_CFG:
+			pci_read_config_dword(dev, pos + sizeof(cap),
+				&hw->notify_off_multiplier);
+			hw->notify_bar = cap.bar;
+			hw->notify_base = get_cap_addr(hw, &cap);
+			IFC_INFO(&dev->dev, "hw->notify_base = %p.\n",
+					hw->notify_base);
+			break;
+		case VIRTIO_PCI_CAP_ISR_CFG:
+			hw->isr = get_cap_addr(hw, &cap);
+			IFC_INFO(&dev->dev, "hw->isr = %p.\n", hw->isr);
+			break;
+		case VIRTIO_PCI_CAP_DEVICE_CFG:
+			hw->dev_cfg = get_cap_addr(hw, &cap);
+			IFC_INFO(&dev->dev, "hw->dev_cfg = %p.\n", hw->dev_cfg);
+			break;
+		}
+next:
+		pos = cap.cap_next;
+	}
+
+	if (hw->common_cfg == NULL || hw->notify_base == NULL ||
+		hw->isr == NULL || hw->dev_cfg == NULL) {
+		IFC_ERR(&dev->dev, "Incomplete PCI capabilities.\n");
+		return -1;
+	}
+
+	for (i = 0; i < (IFCVF_MAX_QUEUE_PAIRS * 2); i++) {
+		iowrite16(i, &hw->common_cfg->queue_select);
+		notify_off = ioread16(&hw->common_cfg->queue_notify_off);
+		hw->notify_addr[i] = (void *)((u8 *)hw->notify_base +
+				notify_off * hw->notify_off_multiplier);
+	}
+
+	hw->lm_cfg = hw->mem_resource[4].addr;
+
+	IFC_INFO(&dev->dev, "PCI capability mapping:\n"
+				"common cfg: %p\n"
+				"notify base: %p\n"
+				"isr cfg: %p\n"
+				"device cfg: %p\n"
+				"multiplier: %u\n",
+				hw->common_cfg,
+				hw->notify_base,
+				hw->isr,
+				hw->dev_cfg,
+				hw->notify_off_multiplier);
+
+	return 0;
+}
+
+static u8 ifcvf_get_status(struct ifcvf_hw *hw)
+{
+	return ioread8(&hw->common_cfg->device_status);
+}
+
+static void ifcvf_set_status(struct ifcvf_hw *hw, u8 status)
+{
+	iowrite8(status, &hw->common_cfg->device_status);
+}
+
+static void ifcvf_reset(struct ifcvf_hw *hw)
+{
+	ifcvf_set_status(hw, 0);
+
+	/* flush status write */
+	ifcvf_get_status(hw);
+	hw->generation++;
+}
+
+static void ifcvf_add_status(struct ifcvf_hw *hw, u8 status)
+{
+	if (status != 0)
+		status |= ifcvf_get_status(hw);
+
+	ifcvf_set_status(hw, status);
+	ifcvf_get_status(hw);
+}
+
+u64 ifcvf_get_features(struct ifcvf_hw *hw)
+{
+	u32 features_lo, features_hi;
+	struct virtio_pci_common_cfg *cfg = hw->common_cfg;
+
+	iowrite32(0, &cfg->device_feature_select);
+	features_lo = ioread32(&cfg->device_feature);
+
+	iowrite32(1, &cfg->device_feature_select);
+	features_hi = ioread32(&cfg->device_feature);
+
+	return ((u64)features_hi << 32) | features_lo;
+}
+static int ifcvf_with_feature(struct ifcvf_hw *hw, u64 bit)
+{
+	return (hw->req_features & (1ULL << bit)) != 0;
+}
+
+static void ifcvf_read_dev_config(struct ifcvf_hw *hw, u64 offset,
+		       void *dst, int length)
+{
+	int i;
+	u8 *p;
+	u8 old_gen, new_gen;
+
+	do {
+		old_gen = ioread8(&hw->common_cfg->config_generation);
+
+		p = dst;
+		for (i = 0; i < length; i++)
+			*p++ = ioread8((u8 *)hw->dev_cfg + offset + i);
+
+		new_gen = ioread8(&hw->common_cfg->config_generation);
+	} while (old_gen != new_gen);
+}
+
+void ifcvf_get_linkstatus(struct ifcvf_hw *hw, u8 *is_linkup)
+{
+	u16 status;
+	u64 host_features;
+
+	host_features = ifcvf_get_features(hw);
+	if (ifcvf_with_feature(hw, VIRTIO_NET_F_STATUS)) {
+		ifcvf_read_dev_config(hw,
+				offsetof(struct ifcvf_net_config, status),
+				&status, sizeof(status));
+		if ((status & VIRTIO_NET_S_LINK_UP) == 0)
+			(*is_linkup) = 1;
+		else
+			(*is_linkup) = 0;
+	} else
+		(*is_linkup) = 0;
+}
+
+static void ifcvf_set_features(struct ifcvf_hw *hw, u64 features)
+{
+	struct virtio_pci_common_cfg *cfg = hw->common_cfg;
+
+	iowrite32(0, &cfg->guest_feature_select);
+	iowrite32(features & ((1ULL << 32) - 1), &cfg->guest_feature);
+
+	iowrite32(1, &cfg->guest_feature_select);
+	iowrite32(features >> 32, &cfg->guest_feature);
+}
+
+static int ifcvf_config_features(struct ifcvf_hw *hw)
+{
+	u64 host_features;
+	struct ifcvf_adapter *ifcvf =
+		container_of(hw, struct ifcvf_adapter, vf);
+
+	host_features = ifcvf_get_features(hw);
+	hw->req_features &= host_features;
+
+	ifcvf_set_features(hw, hw->req_features);
+	ifcvf_add_status(hw, VIRTIO_CONFIG_S_FEATURES_OK);
+
+	if (!(ifcvf_get_status(hw) & VIRTIO_CONFIG_S_FEATURES_OK)) {
+		IFC_ERR(ifcvf->dev, "Failed to set FEATURES_OK status\n");
+		return -EIO;
+	}
+
+	return 0;
+}
+
+static void io_write64_twopart(u64 val, u32 *lo, u32 *hi)
+{
+	iowrite32(val & ((1ULL << 32) - 1), lo);
+	iowrite32(val >> 32, hi);
+}
+
+static int ifcvf_hw_enable(struct ifcvf_hw *hw)
+{
+	struct virtio_pci_common_cfg *cfg;
+	u8 *lm_cfg;
+	u32 i;
+	struct ifcvf_adapter *ifcvf =
+		container_of(hw, struct ifcvf_adapter, vf);
+
+	cfg = hw->common_cfg;
+	lm_cfg = hw->lm_cfg;
+
+	iowrite16(IFCVF_MSI_CONFIG_OFF, &cfg->msix_config);
+	if (ioread16(&cfg->msix_config) == VIRTIO_MSI_NO_VECTOR) {
+		IFC_ERR(ifcvf->dev, "No msix vector for device config.\n");
+		return -1;
+	}
+
+	for (i = 0; i < hw->nr_vring; i++) {
+		iowrite16(i, &cfg->queue_select);
+		io_write64_twopart(hw->vring[i].desc, &cfg->queue_desc_lo,
+				&cfg->queue_desc_hi);
+		io_write64_twopart(hw->vring[i].avail, &cfg->queue_avail_lo,
+				&cfg->queue_avail_hi);
+		io_write64_twopart(hw->vring[i].used, &cfg->queue_used_lo,
+				&cfg->queue_used_hi);
+		iowrite16(hw->vring[i].size, &cfg->queue_size);
+
+		*(u32 *)(lm_cfg + IFCVF_LM_RING_STATE_OFFSET +
+				(i / 2) * IFCVF_LM_CFG_SIZE + (i % 2) * 4) =
+			(u32)hw->vring[i].last_avail_idx |
+			((u32)hw->vring[i].last_used_idx << 16);
+
+		iowrite16(i + IFCVF_MSI_QUEUE_OFF, &cfg->queue_msix_vector);
+		if (ioread16(&cfg->queue_msix_vector) ==
+				VIRTIO_MSI_NO_VECTOR) {
+			IFC_ERR(ifcvf->dev,
+				"No msix vector for queue %u.\n", i);
+			return -1;
+		}
+
+		iowrite16(1, &cfg->queue_enable);
+	}
+
+	return 0;
+}
+
+static void ifcvf_hw_disable(struct ifcvf_hw *hw)
+{
+	u32 i;
+	struct virtio_pci_common_cfg *cfg;
+
+	cfg = hw->common_cfg;
+
+	iowrite16(VIRTIO_MSI_NO_VECTOR, &cfg->msix_config);
+	for (i = 0; i < hw->nr_vring; i++) {
+		iowrite16(i, &cfg->queue_select);
+		iowrite16(0, &cfg->queue_enable);
+		iowrite16(VIRTIO_MSI_NO_VECTOR, &cfg->queue_msix_vector);
+	}
+}
+
+int ifcvf_start_hw(struct ifcvf_hw *hw)
+{
+	ifcvf_reset(hw);
+	ifcvf_add_status(hw, VIRTIO_CONFIG_S_ACKNOWLEDGE);
+	ifcvf_add_status(hw, VIRTIO_CONFIG_S_DRIVER);
+
+	if (ifcvf_config_features(hw) < 0)
+		return -1;
+
+	if (ifcvf_hw_enable(hw) < 0)
+		return -1;
+
+	ifcvf_add_status(hw, VIRTIO_CONFIG_S_DRIVER_OK);
+
+	return 0;
+}
+
+void ifcvf_stop_hw(struct ifcvf_hw *hw)
+{
+	ifcvf_hw_disable(hw);
+	ifcvf_reset(hw);
+}
+
+void ifcvf_enable_logging_vf(struct ifcvf_hw *hw, u64 log_base, u64 log_size)
+{
+	u8 *lm_cfg;
+
+	lm_cfg = hw->lm_cfg;
+
+	*(u32 *)(lm_cfg + IFCVF_LM_BASE_ADDR_LOW) =
+		log_base & IFCVF_32_BIT_MASK;
+
+	*(u32 *)(lm_cfg + IFCVF_LM_BASE_ADDR_HIGH) =
+		(log_base >> 32) & IFCVF_32_BIT_MASK;
+
+	*(u32 *)(lm_cfg + IFCVF_LM_END_ADDR_LOW) =
+		(log_base + log_size) & IFCVF_32_BIT_MASK;
+
+	*(u32 *)(lm_cfg + IFCVF_LM_END_ADDR_HIGH) =
+		((log_base + log_size) >> 32) & IFCVF_32_BIT_MASK;
+
+	*(u32 *)(lm_cfg + IFCVF_LM_LOGGING_CTRL) = IFCVF_LM_ENABLE_VF;
+}
+
+void ifcvf_disable_logging(struct ifcvf_hw *hw)
+{
+	u8 *lm_cfg;
+
+	lm_cfg = hw->lm_cfg;
+	*(u32 *)(lm_cfg + IFCVF_LM_LOGGING_CTRL) = IFCVF_LM_DISABLE;
+}
+
+void ifcvf_notify_queue(struct ifcvf_hw *hw, u16 qid)
+{
+
+	iowrite16(qid, hw->notify_addr[qid]);
+}
+
+u8 ifcvf_get_notify_region(struct ifcvf_hw *hw)
+{
+	return hw->notify_bar;
+}
+
+u64 ifcvf_get_queue_notify_off(struct ifcvf_hw *hw, int qid)
+{
+	return (u8 *)hw->notify_addr[qid] -
+		(u8 *)hw->mem_resource[hw->notify_bar].addr;
+}
diff --git a/drivers/vhost/ifcvf/ifcvf_base.h b/drivers/vhost/ifcvf/ifcvf_base.h
new file mode 100644
index 000000000000..1ab1a1c40f24
--- /dev/null
+++ b/drivers/vhost/ifcvf/ifcvf_base.h
@@ -0,0 +1,137 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/*
+ * Copyright (C) 2019 Intel Corporation.
+ */
+
+#ifndef _IFCVF_H_
+#define _IFCVF_H_
+
+#include <linux/virtio_mdev.h>
+#include <linux/pci.h>
+#include <linux/pci_regs.h>
+#include <uapi/linux/virtio_net.h>
+#include <uapi/linux/virtio_config.h>
+#include <uapi/linux/virtio_pci.h>
+
+#define IFCVF_VENDOR_ID         0x1AF4
+#define IFCVF_DEVICE_ID         0x1041
+#define IFCVF_SUBSYS_VENDOR_ID  0x8086
+#define IFCVF_SUBSYS_DEVICE_ID  0x001A
+
+/*
+ * Some ifcvf feature bits (currently bits 28 through 31) are
+ * reserved for the transport being used (eg. ifcvf_ring), the
+ * rest are per-device feature bits.
+ */
+#define IFCVF_TRANSPORT_F_START 28
+#define IFCVF_TRANSPORT_F_END   34
+
+#define IFC_SUPPORTED_FEATURES \
+		((1ULL << VIRTIO_NET_F_MAC)			| \
+		 (1ULL << VIRTIO_F_ANY_LAYOUT)			| \
+		 (1ULL << VIRTIO_F_VERSION_1)			| \
+		 (1ULL << VHOST_F_LOG_ALL)			| \
+		 (1ULL << VIRTIO_NET_F_GUEST_ANNOUNCE)		| \
+		 (1ULL << VIRTIO_NET_F_CTRL_VQ)			| \
+		 (1ULL << VIRTIO_NET_F_STATUS)			| \
+		 (1ULL << VIRTIO_NET_F_MRG_RXBUF)) /* not fully supported */
+
+#define IFCVF_MAX_QUEUE_PAIRS		1
+#define IFCVF_MAX_QUEUES		2
+
+#define IFCVF_QUEUE_ALIGNMENT		PAGE_SIZE
+
+#define IFCVF_MSI_CONFIG_OFF	0
+#define IFCVF_MSI_QUEUE_OFF	1
+#define IFCVF_PCI_MAX_RESOURCE	6
+
+/* 46 bit CPU physical address, avoid overlap */
+#define LM_IOVA 0x400000000000
+
+#define IFCVF_LM_CFG_SIZE		0x40
+#define IFCVF_LM_RING_STATE_OFFSET	0x20
+
+#define IFCVF_LM_LOGGING_CTRL		0x0
+
+#define IFCVF_LM_BASE_ADDR_LOW		0x10
+#define IFCVF_LM_BASE_ADDR_HIGH		0x14
+#define IFCVF_LM_END_ADDR_LOW		0x18
+#define IFCVF_LM_END_ADDR_HIGH		0x1c
+
+#define IFCVF_LM_DISABLE		0x0
+#define IFCVF_LM_ENABLE_VF		0x1
+#define IFCVF_LM_ENABLE_PF		0x3
+
+#define IFCVF_32_BIT_MASK		0xffffffff
+
+#define IFC_ERR(dev, fmt, ...)	dev_err(dev, fmt, ##__VA_ARGS__)
+#define IFC_INFO(dev, fmt, ...)	dev_info(dev, fmt, ##__VA_ARGS__)
+
+struct ifcvf_net_config {
+	u8    mac[6];
+	u16   status;
+	u16   max_virtqueue_pairs;
+} __packed;
+
+struct ifcvf_pci_mem_resource {
+	u64      phys_addr; /**< Physical address, 0 if not resource. */
+	u64      len;       /**< Length of the resource. */
+	u8       *addr;     /**< Virtual address, NULL when not mapped. */
+};
+
+struct vring_info {
+	u64 desc;
+	u64 avail;
+	u64 used;
+	u16 size;
+	u16 last_avail_idx;
+	u16 last_used_idx;
+	bool ready;
+	char msix_name[256];
+	struct virtio_mdev_callback cb;
+};
+
+struct ifcvf_hw {
+	u8	*isr;
+	u8	notify_bar;
+	u8	*lm_cfg;
+	u8	status;
+	u8	nr_vring;
+	u16	*notify_base;
+	u16	*notify_addr[IFCVF_MAX_QUEUE_PAIRS * 2];
+	u32	generation;
+	u32	notify_off_multiplier;
+	u64	req_features;
+	struct	virtio_pci_common_cfg *common_cfg;
+	struct	ifcvf_net_config *dev_cfg;
+	struct	vring_info vring[IFCVF_MAX_QUEUE_PAIRS * 2];
+	struct	ifcvf_pci_mem_resource mem_resource[IFCVF_PCI_MAX_RESOURCE];
+};
+
+#define IFC_PRIVATE_TO_VF(adapter) \
+	(&((struct ifcvf_adapter *)adapter)->vf)
+
+#define IFCVF_MAX_INTR (IFCVF_MAX_QUEUE_PAIRS * 2 + 1)
+
+struct ifcvf_adapter {
+	struct	device *dev;
+	struct	mutex mdev_lock;
+	int	mdev_count;
+	struct	list_head dma_maps;
+	int	vectors;
+	struct	ifcvf_hw vf;
+};
+
+int ifcvf_init_hw(struct ifcvf_hw *hw, struct pci_dev *dev);
+u64 ifcvf_get_features(struct ifcvf_hw *hw);
+int ifcvf_start_hw(struct ifcvf_hw *hw);
+void ifcvf_stop_hw(struct ifcvf_hw *hw);
+void ifcvf_enable_logging(struct ifcvf_hw *hw, u64 log_base, u64 log_size);
+void ifcvf_enable_logging_vf(struct ifcvf_hw *hw, u64 log_base, u64 log_size);
+void ifcvf_disable_logging(struct ifcvf_hw *hw);
+void ifcvf_notify_queue(struct ifcvf_hw *hw, u16 qid);
+void ifcvf_get_linkstatus(struct ifcvf_hw *hw, u8 *is_linkup);
+u8 ifcvf_get_notify_region(struct ifcvf_hw *hw);
+u64 ifcvf_get_queue_notify_off(struct ifcvf_hw *hw, int qid);
+
+#endif /* _IFCVF_H_ */
-- 
2.16.4

[RFC 2/2] vhost: IFC VF vdpa layer

[Zhu Lingshan]

This commit introduced IFC VF operations for vdpa, which complys to
vhost_mdev interfaces, handles IFC VF initialization,
configuration and removal.

Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
---
 drivers/vhost/ifcvf/ifcvf_main.c | 541 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 541 insertions(+)
 create mode 100644 drivers/vhost/ifcvf/ifcvf_main.c

diff --git a/drivers/vhost/ifcvf/ifcvf_main.c b/drivers/vhost/ifcvf/ifcvf_main.c
new file mode 100644
index 000000000000..c48a29969a85
--- /dev/null
+++ b/drivers/vhost/ifcvf/ifcvf_main.c
@@ -0,0 +1,541 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2019 Intel Corporation.
+ */
+
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/mdev.h>
+#include <linux/pci.h>
+#include <linux/sysfs.h>
+
+#include "ifcvf_base.h"
+
+#define VERSION_STRING	"0.1"
+#define DRIVER_AUTHOR	"Intel Corporation"
+#define IFCVF_DRIVER_NAME	"ifcvf"
+
+static irqreturn_t ifcvf_intr_handler(int irq, void *arg)
+{
+	struct vring_info *vring = arg;
+
+	if (vring->cb.callback)
+		return vring->cb.callback(vring->cb.private);
+
+	return IRQ_HANDLED;
+}
+
+static u64 ifcvf_mdev_get_features(struct mdev_device *mdev)
+{
+	return IFC_SUPPORTED_FEATURES;
+}
+
+static int ifcvf_mdev_set_features(struct mdev_device *mdev, u64 features)
+{
+	struct ifcvf_adapter *adapter = mdev_get_drvdata(mdev);
+	struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(adapter);
+
+	vf->req_features = features;
+
+	return 0;
+}
+
+static u64 ifcvf_mdev_get_vq_state(struct mdev_device *mdev, u16 qid)
+{
+	struct ifcvf_adapter *adapter = mdev_get_drvdata(mdev);
+	struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(adapter);
+
+	return vf->vring[qid].last_avail_idx;
+}
+
+static int ifcvf_mdev_set_vq_state(struct mdev_device *mdev, u16 qid, u64 num)
+{
+	struct ifcvf_adapter *adapter = mdev_get_drvdata(mdev);
+	struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(adapter);
+
+	vf->vring[qid].last_used_idx = num;
+	vf->vring[qid].last_avail_idx = num;
+
+	return 0;
+}
+
+static int ifcvf_mdev_set_vq_address(struct mdev_device *mdev, u16 idx,
+				     u64 desc_area, u64 driver_area,
+				     u64 device_area)
+{
+	struct ifcvf_adapter *adapter = mdev_get_drvdata(mdev);
+	struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(adapter);
+
+	vf->vring[idx].desc = desc_area;
+	vf->vring[idx].avail = driver_area;
+	vf->vring[idx].used = device_area;
+
+	return 0;
+}
+
+static void ifcvf_mdev_set_vq_num(struct mdev_device *mdev, u16 qid, u32 num)
+{
+	struct ifcvf_adapter *adapter = mdev_get_drvdata(mdev);
+	struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(adapter);
+
+	vf->vring[qid].size = num;
+}
+
+static void ifcvf_mdev_set_vq_ready(struct mdev_device *mdev,
+				u16 qid, bool ready)
+{
+
+	struct ifcvf_adapter *adapter = mdev_get_drvdata(mdev);
+	struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(adapter);
+
+	vf->vring[qid].ready = ready;
+}
+
+static bool ifcvf_mdev_get_vq_ready(struct mdev_device *mdev, u16 qid)
+{
+
+	struct ifcvf_adapter *adapter = mdev_get_drvdata(mdev);
+	struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(adapter);
+
+	return vf->vring[qid].ready;
+}
+
+static void ifcvf_mdev_set_vq_cb(struct mdev_device *mdev, u16 idx,
+				 struct virtio_mdev_callback *cb)
+{
+	struct ifcvf_adapter *adapter = mdev_get_drvdata(mdev);
+	struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(adapter);
+
+	vf->vring[idx].cb = *cb;
+}
+
+static void ifcvf_mdev_kick_vq(struct mdev_device *mdev, u16 idx)
+{
+	struct ifcvf_adapter *adapter = mdev_get_drvdata(mdev);
+	struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(adapter);
+
+	ifcvf_notify_queue(vf, idx);
+}
+
+static u8 ifcvf_mdev_get_status(struct mdev_device *mdev)
+{
+	struct ifcvf_adapter *adapter = mdev_get_drvdata(mdev);
+	struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(adapter);
+
+	return vf->status;
+}
+
+static u32 ifcvf_mdev_get_generation(struct mdev_device *mdev)
+{
+	struct ifcvf_adapter *adapter = mdev_get_drvdata(mdev);
+	struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(adapter);
+
+	return vf->generation;
+}
+
+static int ifcvf_mdev_get_version(struct mdev_device *mdev)
+{
+	return VIRTIO_MDEV_VERSION;
+}
+
+static u32 ifcvf_mdev_get_device_id(struct mdev_device *mdev)
+{
+	return IFCVF_DEVICE_ID;
+}
+
+static u32 ifcvf_mdev_get_vendor_id(struct mdev_device *mdev)
+{
+	return IFCVF_VENDOR_ID;
+}
+
+static u16 ifcvf_mdev_get_vq_align(struct mdev_device *mdev)
+{
+	return IFCVF_QUEUE_ALIGNMENT;
+}
+
+static int ifcvf_start_datapath(void *private)
+{
+	int i, ret;
+	struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(private);
+
+	for (i = 0; i < (IFCVF_MAX_QUEUE_PAIRS * 2); i++) {
+		if (!vf->vring[i].ready)
+			break;
+
+		if (!vf->vring[i].size)
+			break;
+
+		if (!vf->vring[i].desc || !vf->vring[i].avail ||
+			!vf->vring[i].used)
+			break;
+	}
+	vf->nr_vring = i;
+
+	ret = ifcvf_start_hw(vf);
+	return ret;
+}
+
+static int ifcvf_stop_datapath(void *private)
+{
+	struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(private);
+	int i;
+
+	for (i = 0; i < IFCVF_MAX_QUEUES; i++)
+		vf->vring[i].cb.callback = NULL;
+
+	ifcvf_stop_hw(vf);
+
+	return 0;
+}
+
+static void ifcvf_reset_vring(struct ifcvf_adapter *adapter)
+{
+	int i;
+	struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(adapter);
+
+	for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) {
+		vf->vring[i].last_used_idx = 0;
+		vf->vring[i].last_avail_idx = 0;
+		vf->vring[i].desc = 0;
+		vf->vring[i].avail = 0;
+		vf->vring[i].used = 0;
+		vf->vring[i].ready = 0;
+		vf->vring->cb.callback = NULL;
+		vf->vring->cb.private = NULL;
+	}
+}
+
+static void ifcvf_mdev_set_status(struct mdev_device *mdev, u8 status)
+{
+	struct ifcvf_adapter *adapter = mdev_get_drvdata(mdev);
+	struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(adapter);
+
+	vf->status = status;
+
+	if (status == 0) {
+		ifcvf_stop_datapath(adapter);
+		ifcvf_reset_vring(adapter);
+		return;
+	}
+
+	if (status & VIRTIO_CONFIG_S_DRIVER_OK) {
+		ifcvf_start_datapath(adapter);
+		return;
+	}
+}
+
+static u16 ifcvf_mdev_get_queue_max(struct mdev_device *mdev)
+{
+	return IFCVF_MAX_QUEUES;
+}
+
+static struct virtio_mdev_device_ops ifc_mdev_ops = {
+	.get_features  = ifcvf_mdev_get_features,
+	.set_features  = ifcvf_mdev_set_features,
+	.get_status    = ifcvf_mdev_get_status,
+	.set_status    = ifcvf_mdev_set_status,
+	.get_queue_max = ifcvf_mdev_get_queue_max,
+	.get_vq_state   = ifcvf_mdev_get_vq_state,
+	.set_vq_state   = ifcvf_mdev_set_vq_state,
+	.set_vq_cb      = ifcvf_mdev_set_vq_cb,
+	.set_vq_ready   = ifcvf_mdev_set_vq_ready,
+	.get_vq_ready	= ifcvf_mdev_get_vq_ready,
+	.set_vq_num     = ifcvf_mdev_set_vq_num,
+	.set_vq_address = ifcvf_mdev_set_vq_address,
+	.kick_vq        = ifcvf_mdev_kick_vq,
+	.get_generation	= ifcvf_mdev_get_generation,
+	.get_version	= ifcvf_mdev_get_version,
+	.get_device_id	= ifcvf_mdev_get_device_id,
+	.get_vendor_id	= ifcvf_mdev_get_vendor_id,
+	.get_vq_align	= ifcvf_mdev_get_vq_align,
+};
+
+static int ifcvf_init_msix(struct ifcvf_adapter *adapter)
+{
+	int vector, i, ret, irq;
+	struct pci_dev *pdev = to_pci_dev(adapter->dev);
+	struct ifcvf_hw *vf = &adapter->vf;
+
+	ret = pci_alloc_irq_vectors(pdev, IFCVF_MAX_INTR,
+			IFCVF_MAX_INTR, PCI_IRQ_MSIX);
+	if (ret < 0) {
+		IFC_ERR(adapter->dev, "Failed to alloc irq vectors.\n");
+		return ret;
+	}
+
+	for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) {
+		vector = i + IFCVF_MSI_QUEUE_OFF;
+		irq = pci_irq_vector(pdev, vector);
+		ret = request_irq(irq, ifcvf_intr_handler, 0,
+				pci_name(pdev), &vf->vring[i]);
+		if (ret) {
+			IFC_ERR(adapter->dev,
+				"Failed to request irq for vq %d.\n", i);
+			return ret;
+		}
+	}
+
+	return 0;
+}
+
+static void ifcvf_destroy_adapter(struct ifcvf_adapter *adapter)
+{
+	int i, vector, irq;
+	struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(adapter);
+	struct pci_dev *pdev = to_pci_dev(adapter->dev);
+
+	for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) {
+		vector = i + IFCVF_MSI_QUEUE_OFF;
+		irq = pci_irq_vector(pdev, vector);
+		free_irq(irq, &vf->vring[i]);
+	}
+}
+
+static ssize_t name_show(struct kobject *kobj, struct device *dev, char *buf)
+{
+	const char *name = "vhost accelerator (virtio ring compatible)";
+
+	return sprintf(buf, "%s\n", name);
+}
+MDEV_TYPE_ATTR_RO(name);
+
+static ssize_t device_api_show(struct kobject *kobj, struct device *dev,
+			       char *buf)
+{
+	return sprintf(buf, "%s\n", VIRTIO_MDEV_DEVICE_API_STRING);
+}
+MDEV_TYPE_ATTR_RO(device_api);
+
+static ssize_t available_instances_show(struct kobject *kobj,
+					struct device *dev, char *buf)
+{
+	struct pci_dev *pdev = to_pci_dev(dev);
+	struct ifcvf_adapter *adapter = pci_get_drvdata(pdev);
+
+	return sprintf(buf, "%d\n", adapter->mdev_count);
+}
+
+MDEV_TYPE_ATTR_RO(available_instances);
+
+static ssize_t type_show(struct kobject *kobj,
+			struct device *dev, char *buf)
+{
+	return sprintf(buf, "%s\n", "net");
+}
+
+MDEV_TYPE_ATTR_RO(type);
+
+
+static struct attribute *mdev_types_attrs[] = {
+	&mdev_type_attr_name.attr,
+	&mdev_type_attr_device_api.attr,
+	&mdev_type_attr_available_instances.attr,
+	&mdev_type_attr_type.attr,
+	NULL,
+};
+
+static struct attribute_group mdev_type_group = {
+	.name  = "vdpa_virtio",
+	.attrs = mdev_types_attrs,
+};
+
+static struct attribute_group *mdev_type_groups[] = {
+	&mdev_type_group,
+	NULL,
+};
+
+const struct attribute_group *mdev_dev_groups[] = {
+	NULL,
+};
+
+static int ifcvf_mdev_create(struct kobject *kobj, struct mdev_device *mdev)
+{
+	struct device *dev = mdev_parent_dev(mdev);
+	struct pci_dev *pdev = to_pci_dev(dev);
+	struct ifcvf_adapter *adapter = pci_get_drvdata(pdev);
+	int ret = 0;
+
+	mutex_lock(&adapter->mdev_lock);
+
+	if (adapter->mdev_count < 1) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	mdev_set_class_id(mdev, MDEV_ID_VHOST);
+	mdev_set_dev_ops(mdev, &ifc_mdev_ops);
+
+	mdev_set_drvdata(mdev, adapter);
+	mdev_set_iommu_device(mdev_dev(mdev), dev);
+
+	INIT_LIST_HEAD(&adapter->dma_maps);
+	adapter->mdev_count--;
+
+out:
+	mutex_unlock(&adapter->mdev_lock);
+	return ret;
+}
+
+static int ifcvf_mdev_remove(struct mdev_device *mdev)
+{
+	struct device *dev = mdev_parent_dev(mdev);
+	struct pci_dev *pdev = to_pci_dev(dev);
+	struct ifcvf_adapter *adapter = pci_get_drvdata(pdev);
+
+	mutex_lock(&adapter->mdev_lock);
+	adapter->mdev_count++;
+	mutex_unlock(&adapter->mdev_lock);
+
+	return 0;
+}
+
+static struct mdev_parent_ops ifcvf_mdev_fops = {
+	.owner			= THIS_MODULE,
+	.supported_type_groups	= mdev_type_groups,
+	.mdev_attr_groups	= mdev_dev_groups,
+	.create			= ifcvf_mdev_create,
+	.remove			= ifcvf_mdev_remove,
+};
+
+static int ifcvf_probe(struct pci_dev *pdev, const struct pci_device_id *id)
+{
+	struct device *dev = &pdev->dev;
+	struct ifcvf_adapter *adapter;
+	struct ifcvf_hw *vf;
+	int ret, i;
+
+	adapter = kzalloc(sizeof(struct ifcvf_adapter), GFP_KERNEL);
+	if (adapter == NULL) {
+		ret = -ENOMEM;
+		goto fail;
+	}
+
+	mutex_init(&adapter->mdev_lock);
+	adapter->mdev_count = 1;
+	adapter->dev = dev;
+
+	pci_set_drvdata(pdev, adapter);
+
+	ret = pci_enable_device(pdev);
+	if (ret) {
+		IFC_ERR(adapter->dev, "Failed to enable device.\n");
+		goto free_adapter;
+	}
+
+	ret = pci_request_regions(pdev, IFCVF_DRIVER_NAME);
+	if (ret) {
+		IFC_ERR(adapter->dev, "Failed to request MMIO region.\n");
+		goto disable_device;
+	}
+
+	pci_set_master(pdev);
+
+	ret = ifcvf_init_msix(adapter);
+	if (ret) {
+		IFC_ERR(adapter->dev, "Failed to initialize MSIX.\n");
+		goto free_msix;
+	}
+
+	vf = &adapter->vf;
+	for (i = 0; i < IFCVF_PCI_MAX_RESOURCE; i++) {
+		vf->mem_resource[i].phys_addr = pci_resource_start(pdev, i);
+		vf->mem_resource[i].len = pci_resource_len(pdev, i);
+		if (!vf->mem_resource[i].len) {
+			vf->mem_resource[i].addr = NULL;
+			continue;
+		}
+
+		vf->mem_resource[i].addr = pci_iomap_range(pdev, i, 0,
+				vf->mem_resource[i].len);
+		if (!vf->mem_resource[i].addr) {
+			IFC_ERR(adapter->dev, "Failed to map IO resource %d\n",
+				i);
+			return -1;
+		}
+	}
+
+	if (ifcvf_init_hw(vf, pdev) < 0)
+		return -1;
+
+	ret = mdev_register_device(dev, &ifcvf_mdev_fops);
+	if (ret) {
+		IFC_ERR(adapter->dev,  "Failed to register mdev device\n");
+		goto destroy_adapter;
+	}
+
+	return 0;
+
+destroy_adapter:
+	ifcvf_destroy_adapter(adapter);
+free_msix:
+	pci_free_irq_vectors(pdev);
+	pci_release_regions(pdev);
+disable_device:
+	pci_disable_device(pdev);
+free_adapter:
+	kfree(adapter);
+fail:
+	return ret;
+}
+
+static void ifcvf_remove(struct pci_dev *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct ifcvf_adapter *adapter = pci_get_drvdata(pdev);
+	struct ifcvf_hw *vf;
+	int i;
+
+	mdev_unregister_device(dev);
+
+	vf = &adapter->vf;
+	for (i = 0; i < IFCVF_PCI_MAX_RESOURCE; i++) {
+		if (vf->mem_resource[i].addr) {
+			pci_iounmap(pdev, vf->mem_resource[i].addr);
+			vf->mem_resource[i].addr = NULL;
+		}
+	}
+
+	ifcvf_destroy_adapter(adapter);
+	pci_free_irq_vectors(pdev);
+
+	pci_release_regions(pdev);
+	pci_disable_device(pdev);
+
+	kfree(adapter);
+}
+
+static struct pci_device_id ifcvf_pci_ids[] = {
+	{ PCI_DEVICE_SUB(IFCVF_VENDOR_ID,
+			IFCVF_DEVICE_ID,
+			IFCVF_SUBSYS_VENDOR_ID,
+			IFCVF_SUBSYS_DEVICE_ID) },
+	{ 0 },
+};
+MODULE_DEVICE_TABLE(pci, ifcvf_pci_ids);
+
+static struct pci_driver ifcvf_driver = {
+	.name     = IFCVF_DRIVER_NAME,
+	.id_table = ifcvf_pci_ids,
+	.probe    = ifcvf_probe,
+	.remove   = ifcvf_remove,
+};
+
+static int __init ifcvf_init_module(void)
+{
+	int ret;
+
+	ret = pci_register_driver(&ifcvf_driver);
+	return ret;
+}
+
+static void __exit ifcvf_exit_module(void)
+{
+	pci_unregister_driver(&ifcvf_driver);
+}
+
+module_init(ifcvf_init_module);
+module_exit(ifcvf_exit_module);
+
+MODULE_LICENSE("GPL v2");
+MODULE_VERSION(VERSION_STRING);
+MODULE_AUTHOR(DRIVER_AUTHOR);
-- 
2.16.4

Re: [RFC 1/2] vhost: IFC VF hardware operation layer

[Simon Horman]

Hi Zhu,

thanks for your patch.

On Wed, Oct 16, 2019 at 09:10:40AM +0800, Zhu Lingshan wrote:
> This commit introduced ifcvf_base layer, which handles IFC VF NIC
> hardware operations and configurations.
> 
> Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
> ---
>  drivers/vhost/ifcvf/ifcvf_base.c | 390 +++++++++++++++++++++++++++++++++++++++
>  drivers/vhost/ifcvf/ifcvf_base.h | 137 ++++++++++++++
>  2 files changed, 527 insertions(+)
>  create mode 100644 drivers/vhost/ifcvf/ifcvf_base.c
>  create mode 100644 drivers/vhost/ifcvf/ifcvf_base.h
> 
> diff --git a/drivers/vhost/ifcvf/ifcvf_base.c b/drivers/vhost/ifcvf/ifcvf_base.c
> new file mode 100644
> index 000000000000..b85e14c9bdcf
> --- /dev/null
> +++ b/drivers/vhost/ifcvf/ifcvf_base.c
> @@ -0,0 +1,390 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (C) 2019 Intel Corporation.
> + */
> +
> +#include "ifcvf_base.h"
> +
> +static void *get_cap_addr(struct ifcvf_hw *hw, struct virtio_pci_cap *cap)
> +{
> +	u8 bar = cap->bar;
> +	u32 length = cap->length;
> +	u32 offset = cap->offset;

The type of the length and offset fields of virtio_pci_cap is __le32.
A conversion, such as le32_to_cpu(), is required in order to access
these fields in host byte order.

> +	struct ifcvf_adapter *ifcvf =
> +		container_of(hw, struct ifcvf_adapter, vf);

As mentioned elsewhere, please use reverse Christmas tree to order local
variables throughout the patch.

Please consider declaring and assigning ifcvf on separate lines
if combining these stretches over more than one line.

> +
> +	if (bar >= IFCVF_PCI_MAX_RESOURCE) {
> +		IFC_ERR(ifcvf->dev,
> +			"Invalid bar number %u to get capabilities.\n", bar);
> +		return NULL;
> +	}
> +
> +	if (offset + length < offset) {
> +		IFC_ERR(ifcvf->dev, "offset(%u) + length(%u) overflows\n",
> +			offset, length);
> +		return NULL;
> +	}
> +
> +	if (offset + length > hw->mem_resource[cap->bar].len) {
> +		IFC_ERR(ifcvf->dev,
> +			"offset(%u) + len(%u) overflows bar%u to get capabilities.\n",
> +			offset, length, bar);
> +		return NULL;
> +	}
> +
> +	return hw->mem_resource[bar].addr + offset;
> +}
> +
> +int ifcvf_read_config_range(struct pci_dev *dev,
> +			uint32_t *val, int size, int where)
> +{
> +	int i;
> +
> +	for (i = 0; i < size; i += 4) {
> +		if (pci_read_config_dword(dev, where + i, val + i / 4) < 0)
> +			return -1;
> +	}

I don't think the {} is needed here.

An error code, such as -EINVAL, should be returned rather than -1.
Likewise elsewhere.

> +	return 0;
> +}
> +
> +int ifcvf_init_hw(struct ifcvf_hw *hw, struct pci_dev *dev)
> +{
> +	int ret;
> +	u8 pos;
> +	struct virtio_pci_cap cap;
> +	u32 i;
> +	u16 notify_off;
> +
> +	ret = pci_read_config_byte(dev, PCI_CAPABILITY_LIST, &pos);
> +
> +	if (ret < 0) {
> +		IFC_ERR(&dev->dev, "failed to read PCI capability list.\n");
> +		return -EIO;
> +	}
> +
> +	while (pos) {
> +		ret = ifcvf_read_config_range(dev, (u32 *)&cap,
> +				sizeof(cap), pos);

sizeof should be white-space aligned vertically with dev.
Likewise elsewhere.

> +
> +		if (ret < 0) {
> +			IFC_ERR(&dev->dev, "failed to get PCI capability at %x",
> +					pos);
> +			break;
> +		}
> +
> +		if (cap.cap_vndr != PCI_CAP_ID_VNDR)
> +			goto next;
> +
> +		IFC_INFO(&dev->dev, "read PCI config:\n"
> +					"config type: %u.\n"
> +					"PCI bar: %u.\n"
> +					"PCI bar offset: %u.\n"
> +					"PCI config len: %u.\n",
> +					cap.cfg_type, cap.bar,
> +					cap.offset, cap.length);
> +
> +		switch (cap.cfg_type) {
> +		case VIRTIO_PCI_CAP_COMMON_CFG:
> +			hw->common_cfg = get_cap_addr(hw, &cap);
> +			IFC_INFO(&dev->dev, "hw->common_cfg = %p.\n",
> +					hw->common_cfg);
> +			break;
> +		case VIRTIO_PCI_CAP_NOTIFY_CFG:
> +			pci_read_config_dword(dev, pos + sizeof(cap),
> +				&hw->notify_off_multiplier);
> +			hw->notify_bar = cap.bar;
> +			hw->notify_base = get_cap_addr(hw, &cap);
> +			IFC_INFO(&dev->dev, "hw->notify_base = %p.\n",
> +					hw->notify_base);
> +			break;
> +		case VIRTIO_PCI_CAP_ISR_CFG:
> +			hw->isr = get_cap_addr(hw, &cap);
> +			IFC_INFO(&dev->dev, "hw->isr = %p.\n", hw->isr);
> +			break;
> +		case VIRTIO_PCI_CAP_DEVICE_CFG:
> +			hw->dev_cfg = get_cap_addr(hw, &cap);
> +			IFC_INFO(&dev->dev, "hw->dev_cfg = %p.\n", hw->dev_cfg);
> +			break;
> +		}
> +next:
> +		pos = cap.cap_next;
> +	}
> +
> +	if (hw->common_cfg == NULL || hw->notify_base == NULL ||
> +		hw->isr == NULL || hw->dev_cfg == NULL) {

hw->isr should be vertically whitespace-alligned with hw->common_cfg.

> +		IFC_ERR(&dev->dev, "Incomplete PCI capabilities.\n");
> +		return -1;
> +	}
> +
> +	for (i = 0; i < (IFCVF_MAX_QUEUE_PAIRS * 2); i++) {

The inner () seem unnecessary here.

> +		iowrite16(i, &hw->common_cfg->queue_select);

Perhaps u16 would be a more appropriate type for i than u32.
Likewise elsewhere.

> +		notify_off = ioread16(&hw->common_cfg->queue_notify_off);
> +		hw->notify_addr[i] = (void *)((u8 *)hw->notify_base +
> +				notify_off * hw->notify_off_multiplier);
> +	}
> +
> +	hw->lm_cfg = hw->mem_resource[4].addr;

A #define rather than directly using 4 may improve readability here.

> +
> +	IFC_INFO(&dev->dev, "PCI capability mapping:\n"
> +				"common cfg: %p\n"
> +				"notify base: %p\n"
> +				"isr cfg: %p\n"
> +				"device cfg: %p\n"
> +				"multiplier: %u\n",
> +				hw->common_cfg,
> +				hw->notify_base,
> +				hw->isr,
> +				hw->dev_cfg,
> +				hw->notify_off_multiplier);
> +
> +	return 0;
> +}
> +
> +static u8 ifcvf_get_status(struct ifcvf_hw *hw)
> +{
> +	return ioread8(&hw->common_cfg->device_status);
> +}
> +
> +static void ifcvf_set_status(struct ifcvf_hw *hw, u8 status)
> +{
> +	iowrite8(status, &hw->common_cfg->device_status);
> +}
> +
> +static void ifcvf_reset(struct ifcvf_hw *hw)
> +{
> +	ifcvf_set_status(hw, 0);
> +
> +	/* flush status write */
> +	ifcvf_get_status(hw);
> +	hw->generation++;
> +}
> +
> +static void ifcvf_add_status(struct ifcvf_hw *hw, u8 status)
> +{
> +	if (status != 0)
> +		status |= ifcvf_get_status(hw);
> +
> +	ifcvf_set_status(hw, status);
> +	ifcvf_get_status(hw);
> +}
> +
> +u64 ifcvf_get_features(struct ifcvf_hw *hw)

ifcvf_get_features only appears to be used in this file in this patchset.
Perhaps it could be made static.

> +{
> +	u32 features_lo, features_hi;
> +	struct virtio_pci_common_cfg *cfg = hw->common_cfg;
> +
> +	iowrite32(0, &cfg->device_feature_select);
> +	features_lo = ioread32(&cfg->device_feature);
> +
> +	iowrite32(1, &cfg->device_feature_select);
> +	features_hi = ioread32(&cfg->device_feature);
> +
> +	return ((u64)features_hi << 32) | features_lo;
> +}

Blank line is needed here.

> +static int ifcvf_with_feature(struct ifcvf_hw *hw, u64 bit)
> +{
> +	return (hw->req_features & (1ULL << bit)) != 0;

I think it would be appropriate to use the BIT_ULL() macro here.
Likewise elsewhere.

> +}
> +
> +static void ifcvf_read_dev_config(struct ifcvf_hw *hw, u64 offset,
> +		       void *dst, int length)
> +{
> +	int i;
> +	u8 *p;
> +	u8 old_gen, new_gen;
> +
> +	do {
> +		old_gen = ioread8(&hw->common_cfg->config_generation);
> +
> +		p = dst;
> +		for (i = 0; i < length; i++)
> +			*p++ = ioread8((u8 *)hw->dev_cfg + offset + i);
> +
> +		new_gen = ioread8(&hw->common_cfg->config_generation);
> +	} while (old_gen != new_gen);

Would it be wise to limit the number of iterations of the loop above?

> +}
> +
> +void ifcvf_get_linkstatus(struct ifcvf_hw *hw, u8 *is_linkup)

This function does not appear to be used in this patchset.
Perhaps it should be removed for now.

Likewise for ifcvf_enable_logging_vf(), ifcvf_disable_logging(),
ifcvf_get_notify_region() and ifcvf_get_queue_notify_off().

> +{
> +	u16 status;
> +	u64 host_features;
> +
> +	host_features = ifcvf_get_features(hw);
> +	if (ifcvf_with_feature(hw, VIRTIO_NET_F_STATUS)) {
> +		ifcvf_read_dev_config(hw,
> +				offsetof(struct ifcvf_net_config, status),
> +				&status, sizeof(status));
> +		if ((status & VIRTIO_NET_S_LINK_UP) == 0)
> +			(*is_linkup) = 1;
> +		else
> +			(*is_linkup) = 0;

The parentheses around *islinkup seem unnecessary.
And perhaps this could be more simply written as:

		*is_linkup = !(status & VIRTIO_NET_S_LINK_UP);
> +	} else
> +		(*is_linkup) = 0;

If one arm of a conditional uses {} then all arms should use {}.
You need to add {} to the else clause.

> +}
> +
> +static void ifcvf_set_features(struct ifcvf_hw *hw, u64 features)
> +{
> +	struct virtio_pci_common_cfg *cfg = hw->common_cfg;
> +
> +	iowrite32(0, &cfg->guest_feature_select);
> +	iowrite32(features & ((1ULL << 32) - 1), &cfg->guest_feature);

Perhaps U32_MAX can be used here.
Likewise elsewhere.

> +
> +	iowrite32(1, &cfg->guest_feature_select);
> +	iowrite32(features >> 32, &cfg->guest_feature);
> +}
> +
> +static int ifcvf_config_features(struct ifcvf_hw *hw)
> +{
> +	u64 host_features;
> +	struct ifcvf_adapter *ifcvf =
> +		container_of(hw, struct ifcvf_adapter, vf);
> +
> +	host_features = ifcvf_get_features(hw);
> +	hw->req_features &= host_features;
> +
> +	ifcvf_set_features(hw, hw->req_features);
> +	ifcvf_add_status(hw, VIRTIO_CONFIG_S_FEATURES_OK);
> +
> +	if (!(ifcvf_get_status(hw) & VIRTIO_CONFIG_S_FEATURES_OK)) {
> +		IFC_ERR(ifcvf->dev, "Failed to set FEATURES_OK status\n");
> +		return -EIO;
> +	}
> +
> +	return 0;
> +}
> +
> +static void io_write64_twopart(u64 val, u32 *lo, u32 *hi)
> +{
> +	iowrite32(val & ((1ULL << 32) - 1), lo);
> +	iowrite32(val >> 32, hi);
> +}

I see this macro is also in virtio_pci_modern.c

Assuming lo and hi aren't guaranteed to be sequential
and thus iowrite64_hi_lo() cannot be used perhaps
it would be good to add a common helper somewhere.

> +
> +static int ifcvf_hw_enable(struct ifcvf_hw *hw)
> +{
> +	struct virtio_pci_common_cfg *cfg;
> +	u8 *lm_cfg;
> +	u32 i;
> +	struct ifcvf_adapter *ifcvf =
> +		container_of(hw, struct ifcvf_adapter, vf);
> +
> +	cfg = hw->common_cfg;
> +	lm_cfg = hw->lm_cfg;
> +
> +	iowrite16(IFCVF_MSI_CONFIG_OFF, &cfg->msix_config);
> +	if (ioread16(&cfg->msix_config) == VIRTIO_MSI_NO_VECTOR) {
> +		IFC_ERR(ifcvf->dev, "No msix vector for device config.\n");
> +		return -1;
> +	}
> +
> +	for (i = 0; i < hw->nr_vring; i++) {
> +		iowrite16(i, &cfg->queue_select);
> +		io_write64_twopart(hw->vring[i].desc, &cfg->queue_desc_lo,
> +				&cfg->queue_desc_hi);
> +		io_write64_twopart(hw->vring[i].avail, &cfg->queue_avail_lo,
> +				&cfg->queue_avail_hi);
> +		io_write64_twopart(hw->vring[i].used, &cfg->queue_used_lo,
> +				&cfg->queue_used_hi);
> +		iowrite16(hw->vring[i].size, &cfg->queue_size);
> +
> +		*(u32 *)(lm_cfg + IFCVF_LM_RING_STATE_OFFSET +
> +				(i / 2) * IFCVF_LM_CFG_SIZE + (i % 2) * 4) =
> +			(u32)hw->vring[i].last_avail_idx |
> +			((u32)hw->vring[i].last_used_idx << 16);
> +
> +		iowrite16(i + IFCVF_MSI_QUEUE_OFF, &cfg->queue_msix_vector);
> +		if (ioread16(&cfg->queue_msix_vector) ==
> +				VIRTIO_MSI_NO_VECTOR) {
> +			IFC_ERR(ifcvf->dev,
> +				"No msix vector for queue %u.\n", i);
> +			return -1;
> +		}
> +
> +		iowrite16(1, &cfg->queue_enable);
> +	}
> +
> +	return 0;
> +}
> +
> +static void ifcvf_hw_disable(struct ifcvf_hw *hw)
> +{
> +	u32 i;
> +	struct virtio_pci_common_cfg *cfg;
> +
> +	cfg = hw->common_cfg;
> +
> +	iowrite16(VIRTIO_MSI_NO_VECTOR, &cfg->msix_config);
> +	for (i = 0; i < hw->nr_vring; i++) {
> +		iowrite16(i, &cfg->queue_select);
> +		iowrite16(0, &cfg->queue_enable);
> +		iowrite16(VIRTIO_MSI_NO_VECTOR, &cfg->queue_msix_vector);
> +	}
> +}
> +
> +int ifcvf_start_hw(struct ifcvf_hw *hw)
> +{
> +	ifcvf_reset(hw);
> +	ifcvf_add_status(hw, VIRTIO_CONFIG_S_ACKNOWLEDGE);
> +	ifcvf_add_status(hw, VIRTIO_CONFIG_S_DRIVER);
> +
> +	if (ifcvf_config_features(hw) < 0)
> +		return -1;
> +
> +	if (ifcvf_hw_enable(hw) < 0)
> +		return -1;
> +
> +	ifcvf_add_status(hw, VIRTIO_CONFIG_S_DRIVER_OK);
> +
> +	return 0;
> +}
> +
> +void ifcvf_stop_hw(struct ifcvf_hw *hw)
> +{
> +	ifcvf_hw_disable(hw);
> +	ifcvf_reset(hw);
> +}
> +
> +void ifcvf_enable_logging_vf(struct ifcvf_hw *hw, u64 log_base, u64 log_size)
> +{
> +	u8 *lm_cfg;
> +
> +	lm_cfg = hw->lm_cfg;
> +
> +	*(u32 *)(lm_cfg + IFCVF_LM_BASE_ADDR_LOW) =
> +		log_base & IFCVF_32_BIT_MASK;
> +
> +	*(u32 *)(lm_cfg + IFCVF_LM_BASE_ADDR_HIGH) =
> +		(log_base >> 32) & IFCVF_32_BIT_MASK;
> +
> +	*(u32 *)(lm_cfg + IFCVF_LM_END_ADDR_LOW) =
> +		(log_base + log_size) & IFCVF_32_BIT_MASK;
> +
> +	*(u32 *)(lm_cfg + IFCVF_LM_END_ADDR_HIGH) =
> +		((log_base + log_size) >> 32) & IFCVF_32_BIT_MASK;
> +
> +	*(u32 *)(lm_cfg + IFCVF_LM_LOGGING_CTRL) = IFCVF_LM_ENABLE_VF;
> +}
> +
> +void ifcvf_disable_logging(struct ifcvf_hw *hw)
> +{
> +	u8 *lm_cfg;
> +
> +	lm_cfg = hw->lm_cfg;
> +	*(u32 *)(lm_cfg + IFCVF_LM_LOGGING_CTRL) = IFCVF_LM_DISABLE;
> +}
> +
> +void ifcvf_notify_queue(struct ifcvf_hw *hw, u16 qid)
> +{
> +

There is an extra blank line above.

> +	iowrite16(qid, hw->notify_addr[qid]);
> +}
> +
> +u8 ifcvf_get_notify_region(struct ifcvf_hw *hw)
> +{
> +	return hw->notify_bar;
> +}
> +
> +u64 ifcvf_get_queue_notify_off(struct ifcvf_hw *hw, int qid)
> +{
> +	return (u8 *)hw->notify_addr[qid] -
> +		(u8 *)hw->mem_resource[hw->notify_bar].addr;
> +}
> diff --git a/drivers/vhost/ifcvf/ifcvf_base.h b/drivers/vhost/ifcvf/ifcvf_base.h
> new file mode 100644
> index 000000000000..1ab1a1c40f24
> --- /dev/null
> +++ b/drivers/vhost/ifcvf/ifcvf_base.h
> @@ -0,0 +1,137 @@
> +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
> +/*
> + * Copyright (C) 2019 Intel Corporation.
> + */
> +
> +#ifndef _IFCVF_H_
> +#define _IFCVF_H_
> +
> +#include <linux/virtio_mdev.h>
> +#include <linux/pci.h>
> +#include <linux/pci_regs.h>
> +#include <uapi/linux/virtio_net.h>
> +#include <uapi/linux/virtio_config.h>
> +#include <uapi/linux/virtio_pci.h>

Are you sure you need all these includes in this header?
It feels that a more minimal set could be found.

> +
> +#define IFCVF_VENDOR_ID         0x1AF4
> +#define IFCVF_DEVICE_ID         0x1041
> +#define IFCVF_SUBSYS_VENDOR_ID  0x8086
> +#define IFCVF_SUBSYS_DEVICE_ID  0x001A
> +
> +/*
> + * Some ifcvf feature bits (currently bits 28 through 31) are
> + * reserved for the transport being used (eg. ifcvf_ring), the
> + * rest are per-device feature bits.
> + */
> +#define IFCVF_TRANSPORT_F_START 28
> +#define IFCVF_TRANSPORT_F_END   34
> +
> +#define IFC_SUPPORTED_FEATURES \
> +		((1ULL << VIRTIO_NET_F_MAC)			| \
> +		 (1ULL << VIRTIO_F_ANY_LAYOUT)			| \
> +		 (1ULL << VIRTIO_F_VERSION_1)			| \
> +		 (1ULL << VHOST_F_LOG_ALL)			| \
> +		 (1ULL << VIRTIO_NET_F_GUEST_ANNOUNCE)		| \
> +		 (1ULL << VIRTIO_NET_F_CTRL_VQ)			| \
> +		 (1ULL << VIRTIO_NET_F_STATUS)			| \
> +		 (1ULL << VIRTIO_NET_F_MRG_RXBUF)) /* not fully supported */
> +
> +#define IFCVF_MAX_QUEUE_PAIRS		1
> +#define IFCVF_MAX_QUEUES		2
> +
> +#define IFCVF_QUEUE_ALIGNMENT		PAGE_SIZE
> +
> +#define IFCVF_MSI_CONFIG_OFF	0
> +#define IFCVF_MSI_QUEUE_OFF	1
> +#define IFCVF_PCI_MAX_RESOURCE	6
> +
> +/* 46 bit CPU physical address, avoid overlap */
> +#define LM_IOVA 0x400000000000
> +
> +#define IFCVF_LM_CFG_SIZE		0x40
> +#define IFCVF_LM_RING_STATE_OFFSET	0x20
> +
> +#define IFCVF_LM_LOGGING_CTRL		0x0
> +
> +#define IFCVF_LM_BASE_ADDR_LOW		0x10
> +#define IFCVF_LM_BASE_ADDR_HIGH		0x14
> +#define IFCVF_LM_END_ADDR_LOW		0x18
> +#define IFCVF_LM_END_ADDR_HIGH		0x1c
> +
> +#define IFCVF_LM_DISABLE		0x0
> +#define IFCVF_LM_ENABLE_VF		0x1
> +#define IFCVF_LM_ENABLE_PF		0x3
> +
> +#define IFCVF_32_BIT_MASK		0xffffffff
> +
> +#define IFC_ERR(dev, fmt, ...)	dev_err(dev, fmt, ##__VA_ARGS__)
> +#define IFC_INFO(dev, fmt, ...)	dev_info(dev, fmt, ##__VA_ARGS__)

Its not clear to me what the value is of the above two macros.
Why not use dev_err() and dev_info() directly?

> +
> +struct ifcvf_net_config {
> +	u8    mac[6];
> +	u16   status;
> +	u16   max_virtqueue_pairs;
> +} __packed;
> +
> +struct ifcvf_pci_mem_resource {
> +	u64      phys_addr; /**< Physical address, 0 if not resource. */
> +	u64      len;       /**< Length of the resource. */
> +	u8       *addr;     /**< Virtual address, NULL when not mapped. */
> +};

I think it would be best to use kernel doc format for the comments above.

> +
> +struct vring_info {
> +	u64 desc;
> +	u64 avail;
> +	u64 used;
> +	u16 size;
> +	u16 last_avail_idx;
> +	u16 last_used_idx;
> +	bool ready;
> +	char msix_name[256];
> +	struct virtio_mdev_callback cb;
> +};
> +
> +struct ifcvf_hw {
> +	u8	*isr;
> +	u8	notify_bar;
> +	u8	*lm_cfg;
> +	u8	status;
> +	u8	nr_vring;

The field arrangement above seems to leave quote a few holes.
Is that intentional?

> +	u16	*notify_base;
> +	u16	*notify_addr[IFCVF_MAX_QUEUE_PAIRS * 2];
> +	u32	generation;
> +	u32	notify_off_multiplier;
> +	u64	req_features;
> +	struct	virtio_pci_common_cfg *common_cfg;
> +	struct	ifcvf_net_config *dev_cfg;
> +	struct	vring_info vring[IFCVF_MAX_QUEUE_PAIRS * 2];
> +	struct	ifcvf_pci_mem_resource mem_resource[IFCVF_PCI_MAX_RESOURCE];
> +};
> +
> +#define IFC_PRIVATE_TO_VF(adapter) \
> +	(&((struct ifcvf_adapter *)adapter)->vf)
> +
> +#define IFCVF_MAX_INTR (IFCVF_MAX_QUEUE_PAIRS * 2 + 1)
> +
> +struct ifcvf_adapter {
> +	struct	device *dev;
> +	struct	mutex mdev_lock;
> +	int	mdev_count;
> +	struct	list_head dma_maps;
> +	int	vectors;

Are dma_maps and vectors field used in this patchset?

> +	struct	ifcvf_hw vf;
> +};
> +
> +int ifcvf_init_hw(struct ifcvf_hw *hw, struct pci_dev *dev);
> +u64 ifcvf_get_features(struct ifcvf_hw *hw);
> +int ifcvf_start_hw(struct ifcvf_hw *hw);
> +void ifcvf_stop_hw(struct ifcvf_hw *hw);
> +void ifcvf_enable_logging(struct ifcvf_hw *hw, u64 log_base, u64 log_size);

ifcvf_enable_logging_vf does not seem to be defined in this patch.

> +void ifcvf_enable_logging_vf(struct ifcvf_hw *hw, u64 log_base, u64 log_size);
> +void ifcvf_disable_logging(struct ifcvf_hw *hw);
> +void ifcvf_notify_queue(struct ifcvf_hw *hw, u16 qid);
> +void ifcvf_get_linkstatus(struct ifcvf_hw *hw, u8 *is_linkup);
> +u8 ifcvf_get_notify_region(struct ifcvf_hw *hw);
> +u64 ifcvf_get_queue_notify_off(struct ifcvf_hw *hw, int qid);
> +
> +#endif /* _IFCVF_H_ */
> -- 
> 2.16.4
> 

Re: [RFC 1/2] vhost: IFC VF hardware operation layer

[Zhu, Lingshan]

On 10/16/2019 5:53 PM, Simon Horman wrote:
> Hi Zhu,
>
> thanks for your patch.
>
> On Wed, Oct 16, 2019 at 09:10:40AM +0800, Zhu Lingshan wrote:
>> This commit introduced ifcvf_base layer, which handles IFC VF NIC
>> hardware operations and configurations.
>>
>> Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
>> ---
>>   drivers/vhost/ifcvf/ifcvf_base.c | 390 +++++++++++++++++++++++++++++++++++++++
>>   drivers/vhost/ifcvf/ifcvf_base.h | 137 ++++++++++++++
>>   2 files changed, 527 insertions(+)
>>   create mode 100644 drivers/vhost/ifcvf/ifcvf_base.c
>>   create mode 100644 drivers/vhost/ifcvf/ifcvf_base.h
>>
>> diff --git a/drivers/vhost/ifcvf/ifcvf_base.c b/drivers/vhost/ifcvf/ifcvf_base.c
>> new file mode 100644
>> index 000000000000..b85e14c9bdcf
>> --- /dev/null
>> +++ b/drivers/vhost/ifcvf/ifcvf_base.c
>> @@ -0,0 +1,390 @@
>> +// SPDX-License-Identifier: GPL-2.0-only
>> +/*
>> + * Copyright (C) 2019 Intel Corporation.
>> + */
>> +
>> +#include "ifcvf_base.h"
>> +
>> +static void *get_cap_addr(struct ifcvf_hw *hw, struct virtio_pci_cap *cap)
>> +{
>> +	u8 bar = cap->bar;
>> +	u32 length = cap->length;
>> +	u32 offset = cap->offset;
> The type of the length and offset fields of virtio_pci_cap is __le32.
> A conversion, such as le32_to_cpu(), is required in order to access
> these fields in host byte order.
Hi Simon, Thanks for your comments, will do this.
>
>> +	struct ifcvf_adapter *ifcvf =
>> +		container_of(hw, struct ifcvf_adapter, vf);
> As mentioned elsewhere, please use reverse Christmas tree to order local
> variables throughout the patch.
>
> Please consider declaring and assigning ifcvf on separate lines
> if combining these stretches over more than one line.
sure, will do.
>
>> +
>> +	if (bar >= IFCVF_PCI_MAX_RESOURCE) {
>> +		IFC_ERR(ifcvf->dev,
>> +			"Invalid bar number %u to get capabilities.\n", bar);
>> +		return NULL;
>> +	}
>> +
>> +	if (offset + length < offset) {
>> +		IFC_ERR(ifcvf->dev, "offset(%u) + length(%u) overflows\n",
>> +			offset, length);
>> +		return NULL;
>> +	}
>> +
>> +	if (offset + length > hw->mem_resource[cap->bar].len) {
>> +		IFC_ERR(ifcvf->dev,
>> +			"offset(%u) + len(%u) overflows bar%u to get capabilities.\n",
>> +			offset, length, bar);
>> +		return NULL;
>> +	}
>> +
>> +	return hw->mem_resource[bar].addr + offset;
>> +}
>> +
>> +int ifcvf_read_config_range(struct pci_dev *dev,
>> +			uint32_t *val, int size, int where)
>> +{
>> +	int i;
>> +
>> +	for (i = 0; i < size; i += 4) {
>> +		if (pci_read_config_dword(dev, where + i, val + i / 4) < 0)
>> +			return -1;
>> +	}
> I don't think the {} is needed here.
>
> An error code, such as -EINVAL, should be returned rather than -1.
> Likewise elsewhere.
sure, will do
>
>> +	return 0;
>> +}
>> +
>> +int ifcvf_init_hw(struct ifcvf_hw *hw, struct pci_dev *dev)
>> +{
>> +	int ret;
>> +	u8 pos;
>> +	struct virtio_pci_cap cap;
>> +	u32 i;
>> +	u16 notify_off;
>> +
>> +	ret = pci_read_config_byte(dev, PCI_CAPABILITY_LIST, &pos);
>> +
>> +	if (ret < 0) {
>> +		IFC_ERR(&dev->dev, "failed to read PCI capability list.\n");
>> +		return -EIO;
>> +	}
>> +
>> +	while (pos) {
>> +		ret = ifcvf_read_config_range(dev, (u32 *)&cap,
>> +				sizeof(cap), pos);
> sizeof should be white-space aligned vertically with dev.
> Likewise elsewhere.
this is to avoid 80 chars limitation, I will try a better indent for 
this and the followings.
>
>> +
>> +		if (ret < 0) {
>> +			IFC_ERR(&dev->dev, "failed to get PCI capability at %x",
>> +					pos);
>> +			break;
>> +		}
>> +
>> +		if (cap.cap_vndr != PCI_CAP_ID_VNDR)
>> +			goto next;
>> +
>> +		IFC_INFO(&dev->dev, "read PCI config:\n"
>> +					"config type: %u.\n"
>> +					"PCI bar: %u.\n"
>> +					"PCI bar offset: %u.\n"
>> +					"PCI config len: %u.\n",
>> +					cap.cfg_type, cap.bar,
>> +					cap.offset, cap.length);
>> +
>> +		switch (cap.cfg_type) {
>> +		case VIRTIO_PCI_CAP_COMMON_CFG:
>> +			hw->common_cfg = get_cap_addr(hw, &cap);
>> +			IFC_INFO(&dev->dev, "hw->common_cfg = %p.\n",
>> +					hw->common_cfg);
>> +			break;
>> +		case VIRTIO_PCI_CAP_NOTIFY_CFG:
>> +			pci_read_config_dword(dev, pos + sizeof(cap),
>> +				&hw->notify_off_multiplier);
>> +			hw->notify_bar = cap.bar;
>> +			hw->notify_base = get_cap_addr(hw, &cap);
>> +			IFC_INFO(&dev->dev, "hw->notify_base = %p.\n",
>> +					hw->notify_base);
>> +			break;
>> +		case VIRTIO_PCI_CAP_ISR_CFG:
>> +			hw->isr = get_cap_addr(hw, &cap);
>> +			IFC_INFO(&dev->dev, "hw->isr = %p.\n", hw->isr);
>> +			break;
>> +		case VIRTIO_PCI_CAP_DEVICE_CFG:
>> +			hw->dev_cfg = get_cap_addr(hw, &cap);
>> +			IFC_INFO(&dev->dev, "hw->dev_cfg = %p.\n", hw->dev_cfg);
>> +			break;
>> +		}
>> +next:
>> +		pos = cap.cap_next;
>> +	}
>> +
>> +	if (hw->common_cfg == NULL || hw->notify_base == NULL ||
>> +		hw->isr == NULL || hw->dev_cfg == NULL) {
> hw->isr should be vertically whitespace-alligned with hw->common_cfg.
>
>> +		IFC_ERR(&dev->dev, "Incomplete PCI capabilities.\n");
>> +		return -1;
>> +	}
>> +
>> +	for (i = 0; i < (IFCVF_MAX_QUEUE_PAIRS * 2); i++) {
> The inner () seem unnecessary here.
sure, thanks
>
>> +		iowrite16(i, &hw->common_cfg->queue_select);
> Perhaps u16 would be a more appropriate type for i than u32.
> Likewise elsewhere.
agreed!
>
>> +		notify_off = ioread16(&hw->common_cfg->queue_notify_off);
>> +		hw->notify_addr[i] = (void *)((u8 *)hw->notify_base +
>> +				notify_off * hw->notify_off_multiplier);
>> +	}
>> +
>> +	hw->lm_cfg = hw->mem_resource[4].addr;
> A #define rather than directly using 4 may improve readability here.
sure
>
>> +
>> +	IFC_INFO(&dev->dev, "PCI capability mapping:\n"
>> +				"common cfg: %p\n"
>> +				"notify base: %p\n"
>> +				"isr cfg: %p\n"
>> +				"device cfg: %p\n"
>> +				"multiplier: %u\n",
>> +				hw->common_cfg,
>> +				hw->notify_base,
>> +				hw->isr,
>> +				hw->dev_cfg,
>> +				hw->notify_off_multiplier);
>> +
>> +	return 0;
>> +}
>> +
>> +static u8 ifcvf_get_status(struct ifcvf_hw *hw)
>> +{
>> +	return ioread8(&hw->common_cfg->device_status);
>> +}
>> +
>> +static void ifcvf_set_status(struct ifcvf_hw *hw, u8 status)
>> +{
>> +	iowrite8(status, &hw->common_cfg->device_status);
>> +}
>> +
>> +static void ifcvf_reset(struct ifcvf_hw *hw)
>> +{
>> +	ifcvf_set_status(hw, 0);
>> +
>> +	/* flush status write */
>> +	ifcvf_get_status(hw);
>> +	hw->generation++;
>> +}
>> +
>> +static void ifcvf_add_status(struct ifcvf_hw *hw, u8 status)
>> +{
>> +	if (status != 0)
>> +		status |= ifcvf_get_status(hw);
>> +
>> +	ifcvf_set_status(hw, status);
>> +	ifcvf_get_status(hw);
>> +}
>> +
>> +u64 ifcvf_get_features(struct ifcvf_hw *hw)
> ifcvf_get_features only appears to be used in this file in this patchset.
> Perhaps it could be made static.
Yes
>
>> +{
>> +	u32 features_lo, features_hi;
>> +	struct virtio_pci_common_cfg *cfg = hw->common_cfg;
>> +
>> +	iowrite32(0, &cfg->device_feature_select);
>> +	features_lo = ioread32(&cfg->device_feature);
>> +
>> +	iowrite32(1, &cfg->device_feature_select);
>> +	features_hi = ioread32(&cfg->device_feature);
>> +
>> +	return ((u64)features_hi << 32) | features_lo;
>> +}
> Blank line is needed here.
will do
>
>> +static int ifcvf_with_feature(struct ifcvf_hw *hw, u64 bit)
>> +{
>> +	return (hw->req_features & (1ULL << bit)) != 0;
> I think it would be appropriate to use the BIT_ULL() macro here.
> Likewise elsewhere.
agreed
>
>> +}
>> +
>> +static void ifcvf_read_dev_config(struct ifcvf_hw *hw, u64 offset,
>> +		       void *dst, int length)
>> +{
>> +	int i;
>> +	u8 *p;
>> +	u8 old_gen, new_gen;
>> +
>> +	do {
>> +		old_gen = ioread8(&hw->common_cfg->config_generation);
>> +
>> +		p = dst;
>> +		for (i = 0; i < length; i++)
>> +			*p++ = ioread8((u8 *)hw->dev_cfg + offset + i);
>> +
>> +		new_gen = ioread8(&hw->common_cfg->config_generation);
>> +	} while (old_gen != new_gen);
> Would it be wise to limit the number of iterations of the loop above?
Thanks but I don't quite get it. This is used to make sure the function 
would get the latest config.
>
>> +}
>> +
>> +void ifcvf_get_linkstatus(struct ifcvf_hw *hw, u8 *is_linkup)
> This function does not appear to be used in this patchset.
> Perhaps it should be removed for now.
>
> Likewise for ifcvf_enable_logging_vf(), ifcvf_disable_logging(),
> ifcvf_get_notify_region() and ifcvf_get_queue_notify_off().
Yes, I will split these "big" patches into small commits in v1 patchset, 
sorry for the inconvenience in this RFC patch.
>> +{
>> +	u16 status;
>> +	u64 host_features;
>> +
>> +	host_features = ifcvf_get_features(hw);
>> +	if (ifcvf_with_feature(hw, VIRTIO_NET_F_STATUS)) {
>> +		ifcvf_read_dev_config(hw,
>> +				offsetof(struct ifcvf_net_config, status),
>> +				&status, sizeof(status));
>> +		if ((status & VIRTIO_NET_S_LINK_UP) == 0)
>> +			(*is_linkup) = 1;
>> +		else
>> +			(*is_linkup) = 0;
> The parentheses around *islinkup seem unnecessary.
> And perhaps this could be more simply written as:
>
> 		*is_linkup = !(status & VIRTIO_NET_S_LINK_UP);
thanks, I may just return a bool as Jason suggested.
>> +	} else
>> +		(*is_linkup) = 0;
> If one arm of a conditional uses {} then all arms should use {}.
> You need to add {} to the else clause.
>
>> +}
>> +
>> +static void ifcvf_set_features(struct ifcvf_hw *hw, u64 features)
>> +{
>> +	struct virtio_pci_common_cfg *cfg = hw->common_cfg;
>> +
>> +	iowrite32(0, &cfg->guest_feature_select);
>> +	iowrite32(features & ((1ULL << 32) - 1), &cfg->guest_feature);
> Perhaps U32_MAX can be used here.
> Likewise elsewhere.
agreed. Thanks!
>
>> +
>> +	iowrite32(1, &cfg->guest_feature_select);
>> +	iowrite32(features >> 32, &cfg->guest_feature);
>> +}
>> +
>> +static int ifcvf_config_features(struct ifcvf_hw *hw)
>> +{
>> +	u64 host_features;
>> +	struct ifcvf_adapter *ifcvf =
>> +		container_of(hw, struct ifcvf_adapter, vf);
>> +
>> +	host_features = ifcvf_get_features(hw);
>> +	hw->req_features &= host_features;
>> +
>> +	ifcvf_set_features(hw, hw->req_features);
>> +	ifcvf_add_status(hw, VIRTIO_CONFIG_S_FEATURES_OK);
>> +
>> +	if (!(ifcvf_get_status(hw) & VIRTIO_CONFIG_S_FEATURES_OK)) {
>> +		IFC_ERR(ifcvf->dev, "Failed to set FEATURES_OK status\n");
>> +		return -EIO;
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static void io_write64_twopart(u64 val, u32 *lo, u32 *hi)
>> +{
>> +	iowrite32(val & ((1ULL << 32) - 1), lo);
>> +	iowrite32(val >> 32, hi);
>> +}
> I see this macro is also in virtio_pci_modern.c
>
> Assuming lo and hi aren't guaranteed to be sequential
> and thus iowrite64_hi_lo() cannot be used perhaps
> it would be good to add a common helper somewhere.
Thanks, I will try after this IFC patchwork, I will cc you.
>
>> +
>> +static int ifcvf_hw_enable(struct ifcvf_hw *hw)
>> +{
>> +	struct virtio_pci_common_cfg *cfg;
>> +	u8 *lm_cfg;
>> +	u32 i;
>> +	struct ifcvf_adapter *ifcvf =
>> +		container_of(hw, struct ifcvf_adapter, vf);
>> +
>> +	cfg = hw->common_cfg;
>> +	lm_cfg = hw->lm_cfg;
>> +
>> +	iowrite16(IFCVF_MSI_CONFIG_OFF, &cfg->msix_config);
>> +	if (ioread16(&cfg->msix_config) == VIRTIO_MSI_NO_VECTOR) {
>> +		IFC_ERR(ifcvf->dev, "No msix vector for device config.\n");
>> +		return -1;
>> +	}
>> +
>> +	for (i = 0; i < hw->nr_vring; i++) {
>> +		iowrite16(i, &cfg->queue_select);
>> +		io_write64_twopart(hw->vring[i].desc, &cfg->queue_desc_lo,
>> +				&cfg->queue_desc_hi);
>> +		io_write64_twopart(hw->vring[i].avail, &cfg->queue_avail_lo,
>> +				&cfg->queue_avail_hi);
>> +		io_write64_twopart(hw->vring[i].used, &cfg->queue_used_lo,
>> +				&cfg->queue_used_hi);
>> +		iowrite16(hw->vring[i].size, &cfg->queue_size);
>> +
>> +		*(u32 *)(lm_cfg + IFCVF_LM_RING_STATE_OFFSET +
>> +				(i / 2) * IFCVF_LM_CFG_SIZE + (i % 2) * 4) =
>> +			(u32)hw->vring[i].last_avail_idx |
>> +			((u32)hw->vring[i].last_used_idx << 16);
>> +
>> +		iowrite16(i + IFCVF_MSI_QUEUE_OFF, &cfg->queue_msix_vector);
>> +		if (ioread16(&cfg->queue_msix_vector) ==
>> +				VIRTIO_MSI_NO_VECTOR) {
>> +			IFC_ERR(ifcvf->dev,
>> +				"No msix vector for queue %u.\n", i);
>> +			return -1;
>> +		}
>> +
>> +		iowrite16(1, &cfg->queue_enable);
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static void ifcvf_hw_disable(struct ifcvf_hw *hw)
>> +{
>> +	u32 i;
>> +	struct virtio_pci_common_cfg *cfg;
>> +
>> +	cfg = hw->common_cfg;
>> +
>> +	iowrite16(VIRTIO_MSI_NO_VECTOR, &cfg->msix_config);
>> +	for (i = 0; i < hw->nr_vring; i++) {
>> +		iowrite16(i, &cfg->queue_select);
>> +		iowrite16(0, &cfg->queue_enable);
>> +		iowrite16(VIRTIO_MSI_NO_VECTOR, &cfg->queue_msix_vector);
>> +	}
>> +}
>> +
>> +int ifcvf_start_hw(struct ifcvf_hw *hw)
>> +{
>> +	ifcvf_reset(hw);
>> +	ifcvf_add_status(hw, VIRTIO_CONFIG_S_ACKNOWLEDGE);
>> +	ifcvf_add_status(hw, VIRTIO_CONFIG_S_DRIVER);
>> +
>> +	if (ifcvf_config_features(hw) < 0)
>> +		return -1;
>> +
>> +	if (ifcvf_hw_enable(hw) < 0)
>> +		return -1;
>> +
>> +	ifcvf_add_status(hw, VIRTIO_CONFIG_S_DRIVER_OK);
>> +
>> +	return 0;
>> +}
>> +
>> +void ifcvf_stop_hw(struct ifcvf_hw *hw)
>> +{
>> +	ifcvf_hw_disable(hw);
>> +	ifcvf_reset(hw);
>> +}
>> +
>> +void ifcvf_enable_logging_vf(struct ifcvf_hw *hw, u64 log_base, u64 log_size)
>> +{
>> +	u8 *lm_cfg;
>> +
>> +	lm_cfg = hw->lm_cfg;
>> +
>> +	*(u32 *)(lm_cfg + IFCVF_LM_BASE_ADDR_LOW) =
>> +		log_base & IFCVF_32_BIT_MASK;
>> +
>> +	*(u32 *)(lm_cfg + IFCVF_LM_BASE_ADDR_HIGH) =
>> +		(log_base >> 32) & IFCVF_32_BIT_MASK;
>> +
>> +	*(u32 *)(lm_cfg + IFCVF_LM_END_ADDR_LOW) =
>> +		(log_base + log_size) & IFCVF_32_BIT_MASK;
>> +
>> +	*(u32 *)(lm_cfg + IFCVF_LM_END_ADDR_HIGH) =
>> +		((log_base + log_size) >> 32) & IFCVF_32_BIT_MASK;
>> +
>> +	*(u32 *)(lm_cfg + IFCVF_LM_LOGGING_CTRL) = IFCVF_LM_ENABLE_VF;
>> +}
>> +
>> +void ifcvf_disable_logging(struct ifcvf_hw *hw)
>> +{
>> +	u8 *lm_cfg;
>> +
>> +	lm_cfg = hw->lm_cfg;
>> +	*(u32 *)(lm_cfg + IFCVF_LM_LOGGING_CTRL) = IFCVF_LM_DISABLE;
>> +}
>> +
>> +void ifcvf_notify_queue(struct ifcvf_hw *hw, u16 qid)
>> +{
>> +
> There is an extra blank line above.
agree
>
>> +	iowrite16(qid, hw->notify_addr[qid]);
>> +}
>> +
>> +u8 ifcvf_get_notify_region(struct ifcvf_hw *hw)
>> +{
>> +	return hw->notify_bar;
>> +}
>> +
>> +u64 ifcvf_get_queue_notify_off(struct ifcvf_hw *hw, int qid)
>> +{
>> +	return (u8 *)hw->notify_addr[qid] -
>> +		(u8 *)hw->mem_resource[hw->notify_bar].addr;
>> +}
>> diff --git a/drivers/vhost/ifcvf/ifcvf_base.h b/drivers/vhost/ifcvf/ifcvf_base.h
>> new file mode 100644
>> index 000000000000..1ab1a1c40f24
>> --- /dev/null
>> +++ b/drivers/vhost/ifcvf/ifcvf_base.h
>> @@ -0,0 +1,137 @@
>> +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
>> +/*
>> + * Copyright (C) 2019 Intel Corporation.
>> + */
>> +
>> +#ifndef _IFCVF_H_
>> +#define _IFCVF_H_
>> +
>> +#include <linux/virtio_mdev.h>
>> +#include <linux/pci.h>
>> +#include <linux/pci_regs.h>
>> +#include <uapi/linux/virtio_net.h>
>> +#include <uapi/linux/virtio_config.h>
>> +#include <uapi/linux/virtio_pci.h>
> Are you sure you need all these includes in this header?
> It feels that a more minimal set could be found.
yeah, I tried, I already removed some.
>
>> +
>> +#define IFCVF_VENDOR_ID         0x1AF4
>> +#define IFCVF_DEVICE_ID         0x1041
>> +#define IFCVF_SUBSYS_VENDOR_ID  0x8086
>> +#define IFCVF_SUBSYS_DEVICE_ID  0x001A
>> +
>> +/*
>> + * Some ifcvf feature bits (currently bits 28 through 31) are
>> + * reserved for the transport being used (eg. ifcvf_ring), the
>> + * rest are per-device feature bits.
>> + */
>> +#define IFCVF_TRANSPORT_F_START 28
>> +#define IFCVF_TRANSPORT_F_END   34
>> +
>> +#define IFC_SUPPORTED_FEATURES \
>> +		((1ULL << VIRTIO_NET_F_MAC)			| \
>> +		 (1ULL << VIRTIO_F_ANY_LAYOUT)			| \
>> +		 (1ULL << VIRTIO_F_VERSION_1)			| \
>> +		 (1ULL << VHOST_F_LOG_ALL)			| \
>> +		 (1ULL << VIRTIO_NET_F_GUEST_ANNOUNCE)		| \
>> +		 (1ULL << VIRTIO_NET_F_CTRL_VQ)			| \
>> +		 (1ULL << VIRTIO_NET_F_STATUS)			| \
>> +		 (1ULL << VIRTIO_NET_F_MRG_RXBUF)) /* not fully supported */
>> +
>> +#define IFCVF_MAX_QUEUE_PAIRS		1
>> +#define IFCVF_MAX_QUEUES		2
>> +
>> +#define IFCVF_QUEUE_ALIGNMENT		PAGE_SIZE
>> +
>> +#define IFCVF_MSI_CONFIG_OFF	0
>> +#define IFCVF_MSI_QUEUE_OFF	1
>> +#define IFCVF_PCI_MAX_RESOURCE	6
>> +
>> +/* 46 bit CPU physical address, avoid overlap */
>> +#define LM_IOVA 0x400000000000
>> +
>> +#define IFCVF_LM_CFG_SIZE		0x40
>> +#define IFCVF_LM_RING_STATE_OFFSET	0x20
>> +
>> +#define IFCVF_LM_LOGGING_CTRL		0x0
>> +
>> +#define IFCVF_LM_BASE_ADDR_LOW		0x10
>> +#define IFCVF_LM_BASE_ADDR_HIGH		0x14
>> +#define IFCVF_LM_END_ADDR_LOW		0x18
>> +#define IFCVF_LM_END_ADDR_HIGH		0x1c
>> +
>> +#define IFCVF_LM_DISABLE		0x0
>> +#define IFCVF_LM_ENABLE_VF		0x1
>> +#define IFCVF_LM_ENABLE_PF		0x3
>> +
>> +#define IFCVF_32_BIT_MASK		0xffffffff
>> +
>> +#define IFC_ERR(dev, fmt, ...)	dev_err(dev, fmt, ##__VA_ARGS__)
>> +#define IFC_INFO(dev, fmt, ...)	dev_info(dev, fmt, ##__VA_ARGS__)
> Its not clear to me what the value is of the above two macros.
> Why not use dev_err() and dev_info() directly?
they are just warps of dev_err and dev_info, I use them to (1) follow 
intel code style. (2)we can ad __func__ if needed.
>
>> +
>> +struct ifcvf_net_config {
>> +	u8    mac[6];
>> +	u16   status;
>> +	u16   max_virtqueue_pairs;
>> +} __packed;
>> +
>> +struct ifcvf_pci_mem_resource {
>> +	u64      phys_addr; /**< Physical address, 0 if not resource. */
>> +	u64      len;       /**< Length of the resource. */
>> +	u8       *addr;     /**< Virtual address, NULL when not mapped. */
>> +};
> I think it would be best to use kernel doc format for the comments above.
agreed
>
>> +
>> +struct vring_info {
>> +	u64 desc;
>> +	u64 avail;
>> +	u64 used;
>> +	u16 size;
>> +	u16 last_avail_idx;
>> +	u16 last_used_idx;
>> +	bool ready;
>> +	char msix_name[256];
>> +	struct virtio_mdev_callback cb;
>> +};
>> +
>> +struct ifcvf_hw {
>> +	u8	*isr;
>> +	u8	notify_bar;
>> +	u8	*lm_cfg;
>> +	u8	status;
>> +	u8	nr_vring;
> The field arrangement above seems to leave quote a few holes.
> Is that intentional?
I tried to place them to meet at least 32bits alignment, any suggestions?
>
>> +	u16	*notify_base;
>> +	u16	*notify_addr[IFCVF_MAX_QUEUE_PAIRS * 2];
>> +	u32	generation;
>> +	u32	notify_off_multiplier;
>> +	u64	req_features;
>> +	struct	virtio_pci_common_cfg *common_cfg;
>> +	struct	ifcvf_net_config *dev_cfg;
>> +	struct	vring_info vring[IFCVF_MAX_QUEUE_PAIRS * 2];
>> +	struct	ifcvf_pci_mem_resource mem_resource[IFCVF_PCI_MAX_RESOURCE];
>> +};
>> +
>> +#define IFC_PRIVATE_TO_VF(adapter) \
>> +	(&((struct ifcvf_adapter *)adapter)->vf)
>> +
>> +#define IFCVF_MAX_INTR (IFCVF_MAX_QUEUE_PAIRS * 2 + 1)
>> +
>> +struct ifcvf_adapter {
>> +	struct	device *dev;
>> +	struct	mutex mdev_lock;
>> +	int	mdev_count;
>> +	struct	list_head dma_maps;
>> +	int	vectors;
> Are dma_maps and vectors field used in this patchset?
I will split them into small commits, thx!
>
>> +	struct	ifcvf_hw vf;
>> +};
>> +
>> +int ifcvf_init_hw(struct ifcvf_hw *hw, struct pci_dev *dev);
>> +u64 ifcvf_get_features(struct ifcvf_hw *hw);
>> +int ifcvf_start_hw(struct ifcvf_hw *hw);
>> +void ifcvf_stop_hw(struct ifcvf_hw *hw);
>> +void ifcvf_enable_logging(struct ifcvf_hw *hw, u64 log_base, u64 log_size);
> ifcvf_enable_logging_vf does not seem to be defined in this patch.
I will remove it since we intend to support LM in next release of driver.
>
>> +void ifcvf_enable_logging_vf(struct ifcvf_hw *hw, u64 log_base, u64 log_size);
>> +void ifcvf_disable_logging(struct ifcvf_hw *hw);
>> +void ifcvf_notify_queue(struct ifcvf_hw *hw, u16 qid);
>> +void ifcvf_get_linkstatus(struct ifcvf_hw *hw, u8 *is_linkup);
>> +u8 ifcvf_get_notify_region(struct ifcvf_hw *hw);
>> +u64 ifcvf_get_queue_notify_off(struct ifcvf_hw *hw, int qid);
>> +
>> +#endif /* _IFCVF_H_ */
>> -- 
>> 2.16.4
>>

Re: [RFC 1/2] vhost: IFC VF hardware operation layer

[Simon Horman]

On Mon, Oct 21, 2019 at 05:55:33PM +0800, Zhu, Lingshan wrote:
> 
> On 10/16/2019 5:53 PM, Simon Horman wrote:
> > Hi Zhu,
> > 
> > thanks for your patch.
> > 
> > On Wed, Oct 16, 2019 at 09:10:40AM +0800, Zhu Lingshan wrote:

...

> > > +static void ifcvf_read_dev_config(struct ifcvf_hw *hw, u64 offset,
> > > +		       void *dst, int length)
> > > +{
> > > +	int i;
> > > +	u8 *p;
> > > +	u8 old_gen, new_gen;
> > > +
> > > +	do {
> > > +		old_gen = ioread8(&hw->common_cfg->config_generation);
> > > +
> > > +		p = dst;
> > > +		for (i = 0; i < length; i++)
> > > +			*p++ = ioread8((u8 *)hw->dev_cfg + offset + i);
> > > +
> > > +		new_gen = ioread8(&hw->common_cfg->config_generation);
> > > +	} while (old_gen != new_gen);
> > Would it be wise to limit the number of iterations of the loop above?
> Thanks but I don't quite get it. This is used to make sure the function
> would get the latest config.

I am worried about the possibility that it will loop forever.
Could that happen?

...

> > > +static void io_write64_twopart(u64 val, u32 *lo, u32 *hi)
> > > +{
> > > +	iowrite32(val & ((1ULL << 32) - 1), lo);
> > > +	iowrite32(val >> 32, hi);
> > > +}
> > I see this macro is also in virtio_pci_modern.c
> > 
> > Assuming lo and hi aren't guaranteed to be sequential
> > and thus iowrite64_hi_lo() cannot be used perhaps
> > it would be good to add a common helper somewhere.
> Thanks, I will try after this IFC patchwork, I will cc you.

Thanks.

...

Re: [RFC 1/2] vhost: IFC VF hardware operation layer

[Jason Wang]

On 2019/10/22 上午12:31, Simon Horman wrote:
> On Mon, Oct 21, 2019 at 05:55:33PM +0800, Zhu, Lingshan wrote:
>> On 10/16/2019 5:53 PM, Simon Horman wrote:
>>> Hi Zhu,
>>>
>>> thanks for your patch.
>>>
>>> On Wed, Oct 16, 2019 at 09:10:40AM +0800, Zhu Lingshan wrote:
> ...
>
>>>> +static void ifcvf_read_dev_config(struct ifcvf_hw *hw, u64 offset,
>>>> +		       void *dst, int length)
>>>> +{
>>>> +	int i;
>>>> +	u8 *p;
>>>> +	u8 old_gen, new_gen;
>>>> +
>>>> +	do {
>>>> +		old_gen = ioread8(&hw->common_cfg->config_generation);
>>>> +
>>>> +		p = dst;
>>>> +		for (i = 0; i < length; i++)
>>>> +			*p++ = ioread8((u8 *)hw->dev_cfg + offset + i);
>>>> +
>>>> +		new_gen = ioread8(&hw->common_cfg->config_generation);
>>>> +	} while (old_gen != new_gen);
>>> Would it be wise to limit the number of iterations of the loop above?
>> Thanks but I don't quite get it. This is used to make sure the function
>> would get the latest config.
> I am worried about the possibility that it will loop forever.
> Could that happen?
>
> ...


My understanding is that the function here is similar to virtio config 
generation [1]. So this can only happen for a buggy hardware.

Thanks

[1] 
https://docs.oasis-open.org/virtio/virtio/v1.1/csprd01/virtio-v1.1-csprd01.html 
Section 2.4.1


>
>>>> +static void io_write64_twopart(u64 val, u32 *lo, u32 *hi)
>>>> +{
>>>> +	iowrite32(val & ((1ULL << 32) - 1), lo);
>>>> +	iowrite32(val >> 32, hi);
>>>> +}
>>> I see this macro is also in virtio_pci_modern.c
>>>
>>> Assuming lo and hi aren't guaranteed to be sequential
>>> and thus iowrite64_hi_lo() cannot be used perhaps
>>> it would be good to add a common helper somewhere.
>> Thanks, I will try after this IFC patchwork, I will cc you.
> Thanks.
>
> ...

Re: [RFC 1/2] vhost: IFC VF hardware operation layer

[Zhu Lingshan]

On 10/22/2019 9:32 AM, Jason Wang wrote:
>
> On 2019/10/22 上午12:31, Simon Horman wrote:
>> On Mon, Oct 21, 2019 at 05:55:33PM +0800, Zhu, Lingshan wrote:
>>> On 10/16/2019 5:53 PM, Simon Horman wrote:
>>>> Hi Zhu,
>>>>
>>>> thanks for your patch.
>>>>
>>>> On Wed, Oct 16, 2019 at 09:10:40AM +0800, Zhu Lingshan wrote:
>> ...
>>
>>>>> +static void ifcvf_read_dev_config(struct ifcvf_hw *hw, u64 offset,
>>>>> +               void *dst, int length)
>>>>> +{
>>>>> +    int i;
>>>>> +    u8 *p;
>>>>> +    u8 old_gen, new_gen;
>>>>> +
>>>>> +    do {
>>>>> +        old_gen = ioread8(&hw->common_cfg->config_generation);
>>>>> +
>>>>> +        p = dst;
>>>>> +        for (i = 0; i < length; i++)
>>>>> +            *p++ = ioread8((u8 *)hw->dev_cfg + offset + i);
>>>>> +
>>>>> +        new_gen = ioread8(&hw->common_cfg->config_generation);
>>>>> +    } while (old_gen != new_gen);
>>>> Would it be wise to limit the number of iterations of the loop above?
>>> Thanks but I don't quite get it. This is used to make sure the function
>>> would get the latest config.
>> I am worried about the possibility that it will loop forever.
>> Could that happen?
>>
>> ...
>
>
> My understanding is that the function here is similar to virtio config 
> generation [1]. So this can only happen for a buggy hardware.
>
> Thanks
>
> [1] 
> https://docs.oasis-open.org/virtio/virtio/v1.1/csprd01/virtio-v1.1-csprd01.html 
> Section 2.4.1
Yes!
>
>
>>
>>>>> +static void io_write64_twopart(u64 val, u32 *lo, u32 *hi)
>>>>> +{
>>>>> +    iowrite32(val & ((1ULL << 32) - 1), lo);
>>>>> +    iowrite32(val >> 32, hi);
>>>>> +}
>>>> I see this macro is also in virtio_pci_modern.c
>>>>
>>>> Assuming lo and hi aren't guaranteed to be sequential
>>>> and thus iowrite64_hi_lo() cannot be used perhaps
>>>> it would be good to add a common helper somewhere.
>>> Thanks, I will try after this IFC patchwork, I will cc you.
>> Thanks.
>>
>> ...
>

Re: [RFC 1/2] vhost: IFC VF hardware operation layer

[Simon Horman]

On Tue, Oct 22, 2019 at 09:32:36AM +0800, Jason Wang wrote:
> 
> On 2019/10/22 上午12:31, Simon Horman wrote:
> > On Mon, Oct 21, 2019 at 05:55:33PM +0800, Zhu, Lingshan wrote:
> > > On 10/16/2019 5:53 PM, Simon Horman wrote:
> > > > Hi Zhu,
> > > > 
> > > > thanks for your patch.
> > > > 
> > > > On Wed, Oct 16, 2019 at 09:10:40AM +0800, Zhu Lingshan wrote:
> > ...
> > 
> > > > > +static void ifcvf_read_dev_config(struct ifcvf_hw *hw, u64 offset,
> > > > > +		       void *dst, int length)
> > > > > +{
> > > > > +	int i;
> > > > > +	u8 *p;
> > > > > +	u8 old_gen, new_gen;
> > > > > +
> > > > > +	do {
> > > > > +		old_gen = ioread8(&hw->common_cfg->config_generation);
> > > > > +
> > > > > +		p = dst;
> > > > > +		for (i = 0; i < length; i++)
> > > > > +			*p++ = ioread8((u8 *)hw->dev_cfg + offset + i);
> > > > > +
> > > > > +		new_gen = ioread8(&hw->common_cfg->config_generation);
> > > > > +	} while (old_gen != new_gen);
> > > > Would it be wise to limit the number of iterations of the loop above?
> > > Thanks but I don't quite get it. This is used to make sure the function
> > > would get the latest config.
> > I am worried about the possibility that it will loop forever.
> > Could that happen?
> > 
> > ...
> 
> 
> My understanding is that the function here is similar to virtio config
> generation [1]. So this can only happen for a buggy hardware.

Ok, so this circles back to my original question.
Should we put a bound on the number of times the loop runs
or should we accept that the kernel locks up if the HW is buggy?

> 
> Thanks
> 
> [1] https://docs.oasis-open.org/virtio/virtio/v1.1/csprd01/virtio-v1.1-csprd01.html
> Section 2.4.1
> 
> 
> > 
> > > > > +static void io_write64_twopart(u64 val, u32 *lo, u32 *hi)
> > > > > +{
> > > > > +	iowrite32(val & ((1ULL << 32) - 1), lo);
> > > > > +	iowrite32(val >> 32, hi);
> > > > > +}
> > > > I see this macro is also in virtio_pci_modern.c
> > > > 
> > > > Assuming lo and hi aren't guaranteed to be sequential
> > > > and thus iowrite64_hi_lo() cannot be used perhaps
> > > > it would be good to add a common helper somewhere.
> > > Thanks, I will try after this IFC patchwork, I will cc you.
> > Thanks.
> > 
> > ...
> 

Re: [RFC 1/2] vhost: IFC VF hardware operation layer

[Jason Wang]

On 2019/10/23 下午6:13, Simon Horman wrote:
> On Tue, Oct 22, 2019 at 09:32:36AM +0800, Jason Wang wrote:
>> On 2019/10/22 上午12:31, Simon Horman wrote:
>>> On Mon, Oct 21, 2019 at 05:55:33PM +0800, Zhu, Lingshan wrote:
>>>> On 10/16/2019 5:53 PM, Simon Horman wrote:
>>>>> Hi Zhu,
>>>>>
>>>>> thanks for your patch.
>>>>>
>>>>> On Wed, Oct 16, 2019 at 09:10:40AM +0800, Zhu Lingshan wrote:
>>> ...
>>>
>>>>>> +static void ifcvf_read_dev_config(struct ifcvf_hw *hw, u64 offset,
>>>>>> +		       void *dst, int length)
>>>>>> +{
>>>>>> +	int i;
>>>>>> +	u8 *p;
>>>>>> +	u8 old_gen, new_gen;
>>>>>> +
>>>>>> +	do {
>>>>>> +		old_gen = ioread8(&hw->common_cfg->config_generation);
>>>>>> +
>>>>>> +		p = dst;
>>>>>> +		for (i = 0; i < length; i++)
>>>>>> +			*p++ = ioread8((u8 *)hw->dev_cfg + offset + i);
>>>>>> +
>>>>>> +		new_gen = ioread8(&hw->common_cfg->config_generation);
>>>>>> +	} while (old_gen != new_gen);
>>>>> Would it be wise to limit the number of iterations of the loop above?
>>>> Thanks but I don't quite get it. This is used to make sure the function
>>>> would get the latest config.
>>> I am worried about the possibility that it will loop forever.
>>> Could that happen?
>>>
>>> ...
>> My understanding is that the function here is similar to virtio config
>> generation [1]. So this can only happen for a buggy hardware.
> Ok, so this circles back to my original question.
> Should we put a bound on the number of times the loop runs
> or should we accept that the kernel locks up if the HW is buggy?
>

I'm not sure, and similar logic has been used by virtio-pci drivers for 
years. Consider this logic is pretty simple and it should not be the 
only place that virito hardware can lock kernel, we can keep it as is.

Actually, there's no need for hardware to implement generation logic, it 
could be emulated by software or even ignored. In new version of 
virtio-mdev, get_generation() is optional, when it was not implemented, 
0 is simply returned by virtio-mdev transport.

Thanks

Re: [RFC 1/2] vhost: IFC VF hardware operation layer

[Simon Horman]

On Wed, Oct 23, 2019 at 06:36:13PM +0800, Jason Wang wrote:
> 
> On 2019/10/23 下午6:13, Simon Horman wrote:
> > On Tue, Oct 22, 2019 at 09:32:36AM +0800, Jason Wang wrote:
> > > On 2019/10/22 上午12:31, Simon Horman wrote:
> > > > On Mon, Oct 21, 2019 at 05:55:33PM +0800, Zhu, Lingshan wrote:
> > > > > On 10/16/2019 5:53 PM, Simon Horman wrote:
> > > > > > Hi Zhu,
> > > > > > 
> > > > > > thanks for your patch.
> > > > > > 
> > > > > > On Wed, Oct 16, 2019 at 09:10:40AM +0800, Zhu Lingshan wrote:
> > > > ...
> > > > 
> > > > > > > +static void ifcvf_read_dev_config(struct ifcvf_hw *hw, u64 offset,
> > > > > > > +		       void *dst, int length)
> > > > > > > +{
> > > > > > > +	int i;
> > > > > > > +	u8 *p;
> > > > > > > +	u8 old_gen, new_gen;
> > > > > > > +
> > > > > > > +	do {
> > > > > > > +		old_gen = ioread8(&hw->common_cfg->config_generation);
> > > > > > > +
> > > > > > > +		p = dst;
> > > > > > > +		for (i = 0; i < length; i++)
> > > > > > > +			*p++ = ioread8((u8 *)hw->dev_cfg + offset + i);
> > > > > > > +
> > > > > > > +		new_gen = ioread8(&hw->common_cfg->config_generation);
> > > > > > > +	} while (old_gen != new_gen);
> > > > > > Would it be wise to limit the number of iterations of the loop above?
> > > > > Thanks but I don't quite get it. This is used to make sure the function
> > > > > would get the latest config.
> > > > I am worried about the possibility that it will loop forever.
> > > > Could that happen?
> > > > 
> > > > ...
> > > My understanding is that the function here is similar to virtio config
> > > generation [1]. So this can only happen for a buggy hardware.
> > Ok, so this circles back to my original question.
> > Should we put a bound on the number of times the loop runs
> > or should we accept that the kernel locks up if the HW is buggy?
> > 
> 
> I'm not sure, and similar logic has been used by virtio-pci drivers for
> years. Consider this logic is pretty simple and it should not be the only
> place that virito hardware can lock kernel, we can keep it as is.

Ok, I accept that there isn't much use fixing this if its idomatic and
there are other places virtio hardware can lock up the kernel.

> Actually, there's no need for hardware to implement generation logic, it
> could be emulated by software or even ignored. In new version of
> virtio-mdev, get_generation() is optional, when it was not implemented, 0 is
> simply returned by virtio-mdev transport.
> 
> Thanks
> 

Re: [RFC 1/2] vhost: IFC VF hardware operation layer

[Zhu, Lingshan]

On 10/16/2019 10:06 AM, Stephen Hemminger wrote:
> On Wed, 16 Oct 2019 09:03:17 +0800 Zhu Lingshan 
> <lingshan.zhu@intel.com> wrote:
>> + IFC_INFO(&dev->dev, "PCI capability mapping:\n" + "common cfg: 
>> %p\n" + "notify base: %p\n" + "isr cfg: %p\n" + "device cfg: %p\n" + 
>> "multiplier: %u\n", + hw->common_cfg, + hw->notify_base, + hw->isr, + 
>> hw->dev_cfg, + hw->notify_off_multiplier); 
> Since kernel messages go to syslog, syslog does not handle multi-line 
> messages very well. This should be a single line. Also, this is the 
> kind of message that should be at the debug level; something that is 
> useful to the driver developers but not something that needs to be 
> filling up every end users log.
Hi Stephen

Thanks for your comments, I have changed them in RFC V2, will send the 
patchset soon.
Thanks,
BR
Zhu Lingshan

Re: [RFC 1/2] vhost: IFC VF hardware operation layer

[Jason Wang]

On 2019/10/21 下午6:00, Zhu, Lingshan wrote:
>
> On 10/16/2019 4:40 PM, Jason Wang wrote:
>>
>> On 2019/10/16 上午9:30, Zhu Lingshan wrote:
>>> This commit introduced ifcvf_base layer, which handles IFC VF NIC
>>> hardware operations and configurations.
>>
>>
>> It's better to describe the difference between ifc vf and virtio in 
>> the commit log or is there a open doc for this?
>>
>>
> Hi Jason,
>
> Sure, I will split these code into small patches with detailed commit 
> logs in v1 patchset.
>>>
>>> Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
>>> ---
>>>   drivers/vhost/ifcvf/ifcvf_base.c | 390 
>>> +++++++++++++++++++++++++++++++++++++++
>>>   drivers/vhost/ifcvf/ifcvf_base.h | 137 ++++++++++++++
>>>   2 files changed, 527 insertions(+)
>>>   create mode 100644 drivers/vhost/ifcvf/ifcvf_base.c
>>>   create mode 100644 drivers/vhost/ifcvf/ifcvf_base.h
>>>
>>> diff --git a/drivers/vhost/ifcvf/ifcvf_base.c 
>>> b/drivers/vhost/ifcvf/ifcvf_base.c
>>> new file mode 100644
>>> index 000000000000..b85e14c9bdcf
>>> --- /dev/null
>>> +++ b/drivers/vhost/ifcvf/ifcvf_base.c
>>> @@ -0,0 +1,390 @@
>>> +// SPDX-License-Identifier: GPL-2.0-only
>>> +/*
>>> + * Copyright (C) 2019 Intel Corporation.
>>> + */
>>> +
>>> +#include "ifcvf_base.h"
>>> +
>>> +static void *get_cap_addr(struct ifcvf_hw *hw, struct 
>>> virtio_pci_cap *cap)
>>> +{
>>> +    u8 bar = cap->bar;
>>> +    u32 length = cap->length;
>>> +    u32 offset = cap->offset;
>>> +    struct ifcvf_adapter *ifcvf =
>>> +        container_of(hw, struct ifcvf_adapter, vf);
>>> +
>>> +    if (bar >= IFCVF_PCI_MAX_RESOURCE) {
>>> +        IFC_ERR(ifcvf->dev,
>>> +            "Invalid bar number %u to get capabilities.\n", bar);
>>> +        return NULL;
>>> +    }
>>> +
>>> +    if (offset + length < offset) {
>>> +        IFC_ERR(ifcvf->dev, "offset(%u) + length(%u) overflows\n",
>>> +            offset, length);
>>> +        return NULL;
>>> +    }
>>> +
>>> +    if (offset + length > hw->mem_resource[cap->bar].len) {
>>> +        IFC_ERR(ifcvf->dev,
>>> +            "offset(%u) + len(%u) overflows bar%u to get 
>>> capabilities.\n",
>>> +            offset, length, bar);
>>> +        return NULL;
>>> +    }
>>> +
>>> +    return hw->mem_resource[bar].addr + offset;
>>> +}
>>> +
>>> +int ifcvf_read_config_range(struct pci_dev *dev,
>>> +            uint32_t *val, int size, int where)
>>> +{
>>> +    int i;
>>> +
>>> +    for (i = 0; i < size; i += 4) {
>>> +        if (pci_read_config_dword(dev, where + i, val + i / 4) < 0)
>>> +            return -1;
>>> +    }
>>> +    return 0;
>>> +}
>>> +
>>> +int ifcvf_init_hw(struct ifcvf_hw *hw, struct pci_dev *dev)
>>> +{
>>> +    int ret;
>>> +    u8 pos;
>>> +    struct virtio_pci_cap cap;
>>> +    u32 i;
>>> +    u16 notify_off;
>>> +
>>> +    ret = pci_read_config_byte(dev, PCI_CAPABILITY_LIST, &pos);
>>> +
>>> +    if (ret < 0) {
>>> +        IFC_ERR(&dev->dev, "failed to read PCI capability list.\n");
>>> +        return -EIO;
>>> +    }
>>> +
>>> +    while (pos) {
>>> +        ret = ifcvf_read_config_range(dev, (u32 *)&cap,
>>> +                sizeof(cap), pos);
>>> +
>>> +        if (ret < 0) {
>>> +            IFC_ERR(&dev->dev, "failed to get PCI capability at %x",
>>> +                    pos);
>>> +            break;
>>> +        }
>>> +
>>> +        if (cap.cap_vndr != PCI_CAP_ID_VNDR)
>>> +            goto next;
>>> +
>>> +        IFC_INFO(&dev->dev, "read PCI config:\n"
>>> +                    "config type: %u.\n"
>>> +                    "PCI bar: %u.\n"
>>> +                    "PCI bar offset: %u.\n"
>>> +                    "PCI config len: %u.\n",
>>> +                    cap.cfg_type, cap.bar,
>>> +                    cap.offset, cap.length);
>>> +
>>> +        switch (cap.cfg_type) {
>>> +        case VIRTIO_PCI_CAP_COMMON_CFG:
>>> +            hw->common_cfg = get_cap_addr(hw, &cap);
>>> +            IFC_INFO(&dev->dev, "hw->common_cfg = %p.\n",
>>> +                    hw->common_cfg);
>>> +            break;
>>> +        case VIRTIO_PCI_CAP_NOTIFY_CFG:
>>> +            pci_read_config_dword(dev, pos + sizeof(cap),
>>> +                &hw->notify_off_multiplier);
>>> +            hw->notify_bar = cap.bar;
>>> +            hw->notify_base = get_cap_addr(hw, &cap);
>>> +            IFC_INFO(&dev->dev, "hw->notify_base = %p.\n",
>>> +                    hw->notify_base);
>>> +            break;
>>> +        case VIRTIO_PCI_CAP_ISR_CFG:
>>> +            hw->isr = get_cap_addr(hw, &cap);
>>> +            IFC_INFO(&dev->dev, "hw->isr = %p.\n", hw->isr);
>>> +            break;
>>> +        case VIRTIO_PCI_CAP_DEVICE_CFG:
>>> +            hw->dev_cfg = get_cap_addr(hw, &cap);
>>> +            IFC_INFO(&dev->dev, "hw->dev_cfg = %p.\n", hw->dev_cfg);
>>> +            break;
>>> +        }
>>> +next:
>>> +        pos = cap.cap_next;
>>> +    }
>>> +
>>> +    if (hw->common_cfg == NULL || hw->notify_base == NULL ||
>>> +        hw->isr == NULL || hw->dev_cfg == NULL) {
>>> +        IFC_ERR(&dev->dev, "Incomplete PCI capabilities.\n");
>>> +        return -1;
>>> +    }
>>> +
>>> +    for (i = 0; i < (IFCVF_MAX_QUEUE_PAIRS * 2); i++) {
>>
>>
>> Any reason for using hard coded queue pairs limit other than the 
>> max_queue_pairs in the net config?
> Hi Jason, Thanks for your kindly comments. For now the driver don't 
> support MQ, we intend to provide a minimal feature sets in this 
> version 1 driver.


Ok, it's better to add comment above IFCVF_MAX_QUEUE_PAIRS.


>>
>>
>>> +        iowrite16(i, &hw->common_cfg->queue_select);
>>> +        notify_off = ioread16(&hw->common_cfg->queue_notify_off);
>>> +        hw->notify_addr[i] = (void *)((u8 *)hw->notify_base +
>>> +                notify_off * hw->notify_off_multiplier);
>>> +    }
>>> +
>>> +    hw->lm_cfg = hw->mem_resource[4].addr;
>>> +
>>> +    IFC_INFO(&dev->dev, "PCI capability mapping:\n"
>>> +                "common cfg: %p\n"
>>> +                "notify base: %p\n"
>>> +                "isr cfg: %p\n"
>>> +                "device cfg: %p\n"
>>> +                "multiplier: %u\n",
>>> +                hw->common_cfg,
>>> +                hw->notify_base,
>>> +                hw->isr,
>>> +                hw->dev_cfg,
>>> +                hw->notify_off_multiplier);
>>> +
>>> +    return 0;
>>> +}
>>> +
>>> +static u8 ifcvf_get_status(struct ifcvf_hw *hw)
>>> +{
>>> +    return ioread8(&hw->common_cfg->device_status);
>>> +}
>>> +
>>> +static void ifcvf_set_status(struct ifcvf_hw *hw, u8 status)
>>> +{
>>> +    iowrite8(status, &hw->common_cfg->device_status);
>>> +}
>>> +
>>> +static void ifcvf_reset(struct ifcvf_hw *hw)
>>> +{
>>> +    ifcvf_set_status(hw, 0);
>>> +
>>> +    /* flush status write */
>>> +    ifcvf_get_status(hw);
>>
>>
>> Why this flush is needed?
>
> accoring to PCIE requirements, this get_status() after a set_status() 
> is used to block the call chain, make sure the hardware has finished 
> the write operation.
>
> It is a bad comment anyway, I will remove it.


Interesting, does this mean if we need also fix the vp_set_status for 
kernel virtio_pci driver?


>
>>
>>
>>> +    hw->generation++;
>>> +}
>>> +
>>> +static void ifcvf_add_status(struct ifcvf_hw *hw, u8 status)
>>> +{
>>> +    if (status != 0)
>>> +        status |= ifcvf_get_status(hw);
>>> +
>>> +    ifcvf_set_status(hw, status);
>>> +    ifcvf_get_status(hw);
>>> +}
>>> +
>>> +u64 ifcvf_get_features(struct ifcvf_hw *hw)
>>> +{
>>> +    u32 features_lo, features_hi;
>>> +    struct virtio_pci_common_cfg *cfg = hw->common_cfg;
>>> +
>>> +    iowrite32(0, &cfg->device_feature_select);
>>> +    features_lo = ioread32(&cfg->device_feature);
>>> +
>>> +    iowrite32(1, &cfg->device_feature_select);
>>> +    features_hi = ioread32(&cfg->device_feature);
>>> +
>>> +    return ((u64)features_hi << 32) | features_lo;
>>> +}
>>> +static int ifcvf_with_feature(struct ifcvf_hw *hw, u64 bit)
>>> +{
>>> +    return (hw->req_features & (1ULL << bit)) != 0;
>>> +}
>>> +
>>> +static void ifcvf_read_dev_config(struct ifcvf_hw *hw, u64 offset,
>>> +               void *dst, int length)
>>> +{
>>> +    int i;
>>> +    u8 *p;
>>> +    u8 old_gen, new_gen;
>>> +
>>> +    do {
>>> +        old_gen = ioread8(&hw->common_cfg->config_generation);
>>> +
>>> +        p = dst;
>>> +        for (i = 0; i < length; i++)
>>> +            *p++ = ioread8((u8 *)hw->dev_cfg + offset + i);
>>> +
>>> +        new_gen = ioread8(&hw->common_cfg->config_generation);
>>> +    } while (old_gen != new_gen);
>>> +}
>>> +
>>> +void ifcvf_get_linkstatus(struct ifcvf_hw *hw, u8 *is_linkup)
>>> +{
>>
>>
>> Why not just return bollean?
> sure, can do.
>>
>>
>>> +    u16 status;
>>> +    u64 host_features;
>>> +
>>> +    host_features = ifcvf_get_features(hw);
>>> +    if (ifcvf_with_feature(hw, VIRTIO_NET_F_STATUS)) {
>>> +        ifcvf_read_dev_config(hw,
>>> +                offsetof(struct ifcvf_net_config, status),
>>> +                &status, sizeof(status));
>>> +        if ((status & VIRTIO_NET_S_LINK_UP) == 0)
>>> +            (*is_linkup) = 1;
>>> +        else
>>> +            (*is_linkup) = 0;
>>> +    } else
>>> +        (*is_linkup) = 0;
>>> +}
>>> +
>>> +static void ifcvf_set_features(struct ifcvf_hw *hw, u64 features)
>>> +{
>>> +    struct virtio_pci_common_cfg *cfg = hw->common_cfg;
>>> +
>>> +    iowrite32(0, &cfg->guest_feature_select);
>>> +    iowrite32(features & ((1ULL << 32) - 1), &cfg->guest_feature);
>>> +
>>> +    iowrite32(1, &cfg->guest_feature_select);
>>> +    iowrite32(features >> 32, &cfg->guest_feature);
>>> +}
>>> +
>>> +static int ifcvf_config_features(struct ifcvf_hw *hw)
>>> +{
>>> +    u64 host_features;
>>> +    struct ifcvf_adapter *ifcvf =
>>> +        container_of(hw, struct ifcvf_adapter, vf);
>>> +
>>> +    host_features = ifcvf_get_features(hw);
>>> +    hw->req_features &= host_features;
>>
>>
>> Is this a must, can't device deal with this?
> I will usehw->req_features directly, thanks for point it out.
>>
>>
>>> +
>>> +    ifcvf_set_features(hw, hw->req_features);
>>> +    ifcvf_add_status(hw, VIRTIO_CONFIG_S_FEATURES_OK);
>>> +
>>> +    if (!(ifcvf_get_status(hw) & VIRTIO_CONFIG_S_FEATURES_OK)) {
>>> +        IFC_ERR(ifcvf->dev, "Failed to set FEATURES_OK status\n");
>>> +        return -EIO;
>>> +    }
>>> +
>>> +    return 0;
>>> +}
>>> +
>>> +static void io_write64_twopart(u64 val, u32 *lo, u32 *hi)
>>> +{
>>> +    iowrite32(val & ((1ULL << 32) - 1), lo);
>>> +    iowrite32(val >> 32, hi);
>>> +}
>>> +
>>> +static int ifcvf_hw_enable(struct ifcvf_hw *hw)
>>> +{
>>> +    struct virtio_pci_common_cfg *cfg;
>>> +    u8 *lm_cfg;
>>> +    u32 i;
>>> +    struct ifcvf_adapter *ifcvf =
>>> +        container_of(hw, struct ifcvf_adapter, vf);
>>> +
>>> +    cfg = hw->common_cfg;
>>> +    lm_cfg = hw->lm_cfg;
>>> +
>>> +    iowrite16(IFCVF_MSI_CONFIG_OFF, &cfg->msix_config);
>>> +    if (ioread16(&cfg->msix_config) == VIRTIO_MSI_NO_VECTOR) {
>>> +        IFC_ERR(ifcvf->dev, "No msix vector for device config.\n");
>>> +        return -1;
>>> +    }
>>> +
>>> +    for (i = 0; i < hw->nr_vring; i++) {
>>> +        iowrite16(i, &cfg->queue_select);
>>> +        io_write64_twopart(hw->vring[i].desc, &cfg->queue_desc_lo,
>>> +                &cfg->queue_desc_hi);
>>> +        io_write64_twopart(hw->vring[i].avail, &cfg->queue_avail_lo,
>>> +                &cfg->queue_avail_hi);
>>> +        io_write64_twopart(hw->vring[i].used, &cfg->queue_used_lo,
>>> +                &cfg->queue_used_hi);
>>> +        iowrite16(hw->vring[i].size, &cfg->queue_size);
>>> +
>>> +        *(u32 *)(lm_cfg + IFCVF_LM_RING_STATE_OFFSET +
>>> +                (i / 2) * IFCVF_LM_CFG_SIZE + (i % 2) * 4) =
>>> +            (u32)hw->vring[i].last_avail_idx |
>>> +            ((u32)hw->vring[i].last_used_idx << 16);
>>> +
>>> +        iowrite16(i + IFCVF_MSI_QUEUE_OFF, &cfg->queue_msix_vector);
>>> +        if (ioread16(&cfg->queue_msix_vector) ==
>>> +                VIRTIO_MSI_NO_VECTOR) {
>>> +            IFC_ERR(ifcvf->dev,
>>> +                "No msix vector for queue %u.\n", i);
>>> +            return -1;
>>> +        }
>>> +
>>> +        iowrite16(1, &cfg->queue_enable);
>>> +    }
>>> +
>>> +    return 0;
>>> +}
>>> +
>>> +static void ifcvf_hw_disable(struct ifcvf_hw *hw)
>>> +{
>>> +    u32 i;
>>> +    struct virtio_pci_common_cfg *cfg;
>>> +
>>> +    cfg = hw->common_cfg;
>>> +
>>> +    iowrite16(VIRTIO_MSI_NO_VECTOR, &cfg->msix_config);
>>> +    for (i = 0; i < hw->nr_vring; i++) {
>>> +        iowrite16(i, &cfg->queue_select);
>>> +        iowrite16(0, &cfg->queue_enable);
>>> +        iowrite16(VIRTIO_MSI_NO_VECTOR, &cfg->queue_msix_vector);
>>> +    }
>>> +}
>>> +
>>> +int ifcvf_start_hw(struct ifcvf_hw *hw)
>>> +{
>>> +    ifcvf_reset(hw);
>>> +    ifcvf_add_status(hw, VIRTIO_CONFIG_S_ACKNOWLEDGE);
>>> +    ifcvf_add_status(hw, VIRTIO_CONFIG_S_DRIVER);
>>> +
>>> +    if (ifcvf_config_features(hw) < 0)
>>> +        return -1;
>>> +
>>> +    if (ifcvf_hw_enable(hw) < 0)
>>> +        return -1;
>>> +
>>> +    ifcvf_add_status(hw, VIRTIO_CONFIG_S_DRIVER_OK);
>>> +
>>> +    return 0;
>>> +}
>>> +
>>> +void ifcvf_stop_hw(struct ifcvf_hw *hw)
>>> +{
>>> +    ifcvf_hw_disable(hw);
>>> +    ifcvf_reset(hw);
>>> +}
>>> +
>>> +void ifcvf_enable_logging_vf(struct ifcvf_hw *hw, u64 log_base, u64 
>>> log_size)
>>> +{
>>> +    u8 *lm_cfg;
>>> +
>>> +    lm_cfg = hw->lm_cfg;
>>> +
>>> +    *(u32 *)(lm_cfg + IFCVF_LM_BASE_ADDR_LOW) =
>>> +        log_base & IFCVF_32_BIT_MASK;
>>> +
>>> +    *(u32 *)(lm_cfg + IFCVF_LM_BASE_ADDR_HIGH) =
>>> +        (log_base >> 32) & IFCVF_32_BIT_MASK;
>>> +
>>> +    *(u32 *)(lm_cfg + IFCVF_LM_END_ADDR_LOW) =
>>> +        (log_base + log_size) & IFCVF_32_BIT_MASK;
>>> +
>>> +    *(u32 *)(lm_cfg + IFCVF_LM_END_ADDR_HIGH) =
>>> +        ((log_base + log_size) >> 32) & IFCVF_32_BIT_MASK;
>>> +
>>> +    *(u32 *)(lm_cfg + IFCVF_LM_LOGGING_CTRL) = IFCVF_LM_ENABLE_VF;
>>> +}
>>
>>
>> Is the device using iova or gpa for the logging?
> gpa, I will remove all LM related functions since we plan to support 
> LM in next version driver.


Ok, that's why vIOMMU is not fully supported in the case. So we need

1) Filter out _F_IOMMU_PLATFORM for vhost-mdev

2) Can keep it for virtio-mdev

But one more question is: how device know which kinds of address it is 
used? Or I guess the device doesn't know the only problem is IOVA->GPA 
conversion in the case of vIOMMU. If this is true, maybe we can 
introduce API to sync dirty pages and do the conversion there instead of 
using share memory as the log as what current vhost did.


>>
>>
>>> +
>>> +void ifcvf_disable_logging(struct ifcvf_hw *hw)
>>> +{
>>> +    u8 *lm_cfg;
>>> +
>>> +    lm_cfg = hw->lm_cfg;
>>> +    *(u32 *)(lm_cfg + IFCVF_LM_LOGGING_CTRL) = IFCVF_LM_DISABLE;
>>> +}
>>> +
>>> +void ifcvf_notify_queue(struct ifcvf_hw *hw, u16 qid)
>>> +{
>>> +
>>> +    iowrite16(qid, hw->notify_addr[qid]);
>>> +}
>>> +
>>> +u8 ifcvf_get_notify_region(struct ifcvf_hw *hw)
>>> +{
>>> +    return hw->notify_bar;
>>> +}
>>> +
>>> +u64 ifcvf_get_queue_notify_off(struct ifcvf_hw *hw, int qid)
>>> +{
>>> +    return (u8 *)hw->notify_addr[qid] -
>>> +        (u8 *)hw->mem_resource[hw->notify_bar].addr;
>>> +}
>>> diff --git a/drivers/vhost/ifcvf/ifcvf_base.h 
>>> b/drivers/vhost/ifcvf/ifcvf_base.h
>>> new file mode 100644
>>> index 000000000000..1ab1a1c40f24
>>> --- /dev/null
>>> +++ b/drivers/vhost/ifcvf/ifcvf_base.h
>>> @@ -0,0 +1,137 @@
>>> +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
>>> +/*
>>> + * Copyright (C) 2019 Intel Corporation.
>>> + */
>>> +
>>> +#ifndef _IFCVF_H_
>>> +#define _IFCVF_H_
>>> +
>>> +#include <linux/virtio_mdev.h>
>>> +#include <linux/pci.h>
>>> +#include <linux/pci_regs.h>
>>> +#include <uapi/linux/virtio_net.h>
>>> +#include <uapi/linux/virtio_config.h>
>>> +#include <uapi/linux/virtio_pci.h>
>>> +
>>> +#define IFCVF_VENDOR_ID         0x1AF4
>>> +#define IFCVF_DEVICE_ID         0x1041
>>> +#define IFCVF_SUBSYS_VENDOR_ID  0x8086
>>> +#define IFCVF_SUBSYS_DEVICE_ID  0x001A
>>> +
>>> +/*
>>> + * Some ifcvf feature bits (currently bits 28 through 31) are
>>> + * reserved for the transport being used (eg. ifcvf_ring), the
>>> + * rest are per-device feature bits.
>>> + */
>>> +#define IFCVF_TRANSPORT_F_START 28
>>> +#define IFCVF_TRANSPORT_F_END   34
>>> +
>>> +#define IFC_SUPPORTED_FEATURES \
>>> +        ((1ULL << VIRTIO_NET_F_MAC)            | \
>>> +         (1ULL << VIRTIO_F_ANY_LAYOUT)            | \
>>> +         (1ULL << VIRTIO_F_VERSION_1) | \
>>> +         (1ULL << VHOST_F_LOG_ALL)            | \
>>> +         (1ULL << VIRTIO_NET_F_GUEST_ANNOUNCE)        | \
>>> +         (1ULL << VIRTIO_NET_F_CTRL_VQ)            | \
>>> +         (1ULL << VIRTIO_NET_F_STATUS)            | \
>>> +         (1ULL << VIRTIO_NET_F_MRG_RXBUF)) /* not fully supported */
>>> +
>>> +#define IFCVF_MAX_QUEUE_PAIRS        1
>>> +#define IFCVF_MAX_QUEUES        2
>>> +
>>> +#define IFCVF_QUEUE_ALIGNMENT        PAGE_SIZE
>>> +
>>> +#define IFCVF_MSI_CONFIG_OFF    0
>>> +#define IFCVF_MSI_QUEUE_OFF    1
>>> +#define IFCVF_PCI_MAX_RESOURCE    6
>>> +
>>> +/* 46 bit CPU physical address, avoid overlap */
>>> +#define LM_IOVA 0x400000000000
>>> +
>>> +#define IFCVF_LM_CFG_SIZE        0x40
>>> +#define IFCVF_LM_RING_STATE_OFFSET    0x20
>>> +
>>> +#define IFCVF_LM_LOGGING_CTRL        0x0
>>> +
>>> +#define IFCVF_LM_BASE_ADDR_LOW        0x10
>>> +#define IFCVF_LM_BASE_ADDR_HIGH        0x14
>>> +#define IFCVF_LM_END_ADDR_LOW        0x18
>>> +#define IFCVF_LM_END_ADDR_HIGH        0x1c
>>> +
>>> +#define IFCVF_LM_DISABLE        0x0
>>> +#define IFCVF_LM_ENABLE_VF        0x1
>>> +#define IFCVF_LM_ENABLE_PF        0x3
>>> +
>>> +#define IFCVF_32_BIT_MASK        0xffffffff
>>> +
>>> +#define IFC_ERR(dev, fmt, ...)    dev_err(dev, fmt, ##__VA_ARGS__)
>>> +#define IFC_INFO(dev, fmt, ...)    dev_info(dev, fmt, ##__VA_ARGS__)
>>> +
>>> +struct ifcvf_net_config {
>>> +    u8    mac[6];
>>> +    u16   status;
>>> +    u16   max_virtqueue_pairs;
>>> +} __packed;
>>> +
>>> +struct ifcvf_pci_mem_resource {
>>> +    u64      phys_addr; /**< Physical address, 0 if not resource. */
>>> +    u64      len;       /**< Length of the resource. */
>>> +    u8       *addr;     /**< Virtual address, NULL when not mapped. */
>>> +};
>>> +
>>> +struct vring_info {
>>> +    u64 desc;
>>> +    u64 avail;
>>> +    u64 used;
>>> +    u16 size;
>>> +    u16 last_avail_idx;
>>> +    u16 last_used_idx;
>>> +    bool ready;
>>> +    char msix_name[256];
>>> +    struct virtio_mdev_callback cb;
>>> +};
>>> +
>>> +struct ifcvf_hw {
>>> +    u8    *isr;
>>> +    u8    notify_bar;
>>> +    u8    *lm_cfg;
>>> +    u8    status;
>>> +    u8    nr_vring;
>>
>>
>> Is the the number of queue currently used?
> Do you mean nr_vring? Yes it is used in hardware enable / disable 
> functions.
>>
>>
>>> +    u16    *notify_base;
>>> +    u16    *notify_addr[IFCVF_MAX_QUEUE_PAIRS * 2];
>>> +    u32    generation;
>>> +    u32    notify_off_multiplier;
>>> +    u64    req_features;
>>> +    struct    virtio_pci_common_cfg *common_cfg;
>>> +    struct    ifcvf_net_config *dev_cfg;
>>> +    struct    vring_info vring[IFCVF_MAX_QUEUE_PAIRS * 2];
>>> +    struct    ifcvf_pci_mem_resource 
>>> mem_resource[IFCVF_PCI_MAX_RESOURCE];
>>> +};
>>> +
>>> +#define IFC_PRIVATE_TO_VF(adapter) \
>>> +    (&((struct ifcvf_adapter *)adapter)->vf)
>>> +
>>> +#define IFCVF_MAX_INTR (IFCVF_MAX_QUEUE_PAIRS * 2 + 1)
>>
>>
>> The extra one means the config interrupt?
> Yes.


Ok, when we support control vq, it should be changed to 2*N + 2.

Thanks


>>
>>
>>> +
>>> +struct ifcvf_adapter {
>>> +    struct    device *dev;
>>> +    struct    mutex mdev_lock;
>>
>>
>> Not used in the patch, move to next one?
> Sure, these not used ones will be moved to small patches where they 
> are used in v1 patchset.
>>
>>
>>> +    int    mdev_count;
>>
>>
>> Not used.
>>
>>
>>> +    struct    list_head dma_maps;
>>
>>
>> This is not used.
>>
>> Thanks
>>
>>
>>> +    int    vectors;
>>> +    struct    ifcvf_hw vf;
>>> +};
>>> +
>>> +int ifcvf_init_hw(struct ifcvf_hw *hw, struct pci_dev *dev);
>>> +u64 ifcvf_get_features(struct ifcvf_hw *hw);
>>> +int ifcvf_start_hw(struct ifcvf_hw *hw);
>>> +void ifcvf_stop_hw(struct ifcvf_hw *hw);
>>> +void ifcvf_enable_logging(struct ifcvf_hw *hw, u64 log_base, u64 
>>> log_size);
>>> +void ifcvf_enable_logging_vf(struct ifcvf_hw *hw, u64 log_base, u64 
>>> log_size);
>>> +void ifcvf_disable_logging(struct ifcvf_hw *hw);
>>> +void ifcvf_notify_queue(struct ifcvf_hw *hw, u16 qid);
>>> +void ifcvf_get_linkstatus(struct ifcvf_hw *hw, u8 *is_linkup);
>>> +u8 ifcvf_get_notify_region(struct ifcvf_hw *hw);
>>> +u64 ifcvf_get_queue_notify_off(struct ifcvf_hw *hw, int qid);
>>> +
>>> +#endif /* _IFCVF_H_ */

Re: [RFC 1/2] vhost: IFC VF hardware operation layer

[Jason Wang]

On 2019/10/21 下午5:57, Zhu, Lingshan wrote:
>
> On 10/16/2019 4:45 PM, Jason Wang wrote:
>>
>> On 2019/10/16 上午9:30, Zhu Lingshan wrote:
>>> + */
>>> +#define IFCVF_TRANSPORT_F_START 28
>>> +#define IFCVF_TRANSPORT_F_END   34
>>> +
>>> +#define IFC_SUPPORTED_FEATURES \
>>> +        ((1ULL << VIRTIO_NET_F_MAC)            | \
>>> +         (1ULL << VIRTIO_F_ANY_LAYOUT)            | \
>>> +         (1ULL << VIRTIO_F_VERSION_1) | \
>>> +         (1ULL << VHOST_F_LOG_ALL)            | \
>>
>>
>> Let's avoid using VHOST_F_LOG_ALL, using the get_mdev_features() 
>> instead.
> Thanks, I will remove VHOST_F_LOG_ALL
>>
>>
>>> +         (1ULL << VIRTIO_NET_F_GUEST_ANNOUNCE)        | \
>>> +         (1ULL << VIRTIO_NET_F_CTRL_VQ)            | \
>>> +         (1ULL << VIRTIO_NET_F_STATUS)            | \
>>> +         (1ULL << VIRTIO_NET_F_MRG_RXBUF)) /* not fully supported */
>>
>>
>> Why not having VIRTIO_F_IOMMU_PLATFORM and VIRTIO_F_ORDER_PLATFORM?
>
> I will add VIRTIO_F_ORDER_PLATFORM, for VIRTIO_F_IOMMU_PLATFORM, if we 
> add this bit, QEMU may enable viommu, can cause troubles in LM


Qemu has mature support of vIOMMU support for VFIO device, it can shadow 
IO page tables and setup them through DMA ioctl of vfio containers. Any 
issue you saw here?

Btw, to test them quickly, you can implement set_config/get_config and 
test them through virtio-mdev/kernel drivers as well.

Thanks


> (through we don't support LM in this version driver)
>
> Thanks,
> BR
> Zhu Lingshan
>>
>> Thanks
>>

Re: [RFC 1/2] vhost: IFC VF hardware operation layer

[Zhu, Lingshan]

On 10/16/2019 4:40 PM, Jason Wang wrote:
>
> On 2019/10/16 上午9:30, Zhu Lingshan wrote:
>> This commit introduced ifcvf_base layer, which handles IFC VF NIC
>> hardware operations and configurations.
>
>
> It's better to describe the difference between ifc vf and virtio in 
> the commit log or is there a open doc for this?
>
>
Hi Jason,

Sure, I will split these code into small patches with detailed commit 
logs in v1 patchset.
>>
>> Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
>> ---
>>   drivers/vhost/ifcvf/ifcvf_base.c | 390 
>> +++++++++++++++++++++++++++++++++++++++
>>   drivers/vhost/ifcvf/ifcvf_base.h | 137 ++++++++++++++
>>   2 files changed, 527 insertions(+)
>>   create mode 100644 drivers/vhost/ifcvf/ifcvf_base.c
>>   create mode 100644 drivers/vhost/ifcvf/ifcvf_base.h
>>
>> diff --git a/drivers/vhost/ifcvf/ifcvf_base.c 
>> b/drivers/vhost/ifcvf/ifcvf_base.c
>> new file mode 100644
>> index 000000000000..b85e14c9bdcf
>> --- /dev/null
>> +++ b/drivers/vhost/ifcvf/ifcvf_base.c
>> @@ -0,0 +1,390 @@
>> +// SPDX-License-Identifier: GPL-2.0-only
>> +/*
>> + * Copyright (C) 2019 Intel Corporation.
>> + */
>> +
>> +#include "ifcvf_base.h"
>> +
>> +static void *get_cap_addr(struct ifcvf_hw *hw, struct virtio_pci_cap 
>> *cap)
>> +{
>> +    u8 bar = cap->bar;
>> +    u32 length = cap->length;
>> +    u32 offset = cap->offset;
>> +    struct ifcvf_adapter *ifcvf =
>> +        container_of(hw, struct ifcvf_adapter, vf);
>> +
>> +    if (bar >= IFCVF_PCI_MAX_RESOURCE) {
>> +        IFC_ERR(ifcvf->dev,
>> +            "Invalid bar number %u to get capabilities.\n", bar);
>> +        return NULL;
>> +    }
>> +
>> +    if (offset + length < offset) {
>> +        IFC_ERR(ifcvf->dev, "offset(%u) + length(%u) overflows\n",
>> +            offset, length);
>> +        return NULL;
>> +    }
>> +
>> +    if (offset + length > hw->mem_resource[cap->bar].len) {
>> +        IFC_ERR(ifcvf->dev,
>> +            "offset(%u) + len(%u) overflows bar%u to get 
>> capabilities.\n",
>> +            offset, length, bar);
>> +        return NULL;
>> +    }
>> +
>> +    return hw->mem_resource[bar].addr + offset;
>> +}
>> +
>> +int ifcvf_read_config_range(struct pci_dev *dev,
>> +            uint32_t *val, int size, int where)
>> +{
>> +    int i;
>> +
>> +    for (i = 0; i < size; i += 4) {
>> +        if (pci_read_config_dword(dev, where + i, val + i / 4) < 0)
>> +            return -1;
>> +    }
>> +    return 0;
>> +}
>> +
>> +int ifcvf_init_hw(struct ifcvf_hw *hw, struct pci_dev *dev)
>> +{
>> +    int ret;
>> +    u8 pos;
>> +    struct virtio_pci_cap cap;
>> +    u32 i;
>> +    u16 notify_off;
>> +
>> +    ret = pci_read_config_byte(dev, PCI_CAPABILITY_LIST, &pos);
>> +
>> +    if (ret < 0) {
>> +        IFC_ERR(&dev->dev, "failed to read PCI capability list.\n");
>> +        return -EIO;
>> +    }
>> +
>> +    while (pos) {
>> +        ret = ifcvf_read_config_range(dev, (u32 *)&cap,
>> +                sizeof(cap), pos);
>> +
>> +        if (ret < 0) {
>> +            IFC_ERR(&dev->dev, "failed to get PCI capability at %x",
>> +                    pos);
>> +            break;
>> +        }
>> +
>> +        if (cap.cap_vndr != PCI_CAP_ID_VNDR)
>> +            goto next;
>> +
>> +        IFC_INFO(&dev->dev, "read PCI config:\n"
>> +                    "config type: %u.\n"
>> +                    "PCI bar: %u.\n"
>> +                    "PCI bar offset: %u.\n"
>> +                    "PCI config len: %u.\n",
>> +                    cap.cfg_type, cap.bar,
>> +                    cap.offset, cap.length);
>> +
>> +        switch (cap.cfg_type) {
>> +        case VIRTIO_PCI_CAP_COMMON_CFG:
>> +            hw->common_cfg = get_cap_addr(hw, &cap);
>> +            IFC_INFO(&dev->dev, "hw->common_cfg = %p.\n",
>> +                    hw->common_cfg);
>> +            break;
>> +        case VIRTIO_PCI_CAP_NOTIFY_CFG:
>> +            pci_read_config_dword(dev, pos + sizeof(cap),
>> +                &hw->notify_off_multiplier);
>> +            hw->notify_bar = cap.bar;
>> +            hw->notify_base = get_cap_addr(hw, &cap);
>> +            IFC_INFO(&dev->dev, "hw->notify_base = %p.\n",
>> +                    hw->notify_base);
>> +            break;
>> +        case VIRTIO_PCI_CAP_ISR_CFG:
>> +            hw->isr = get_cap_addr(hw, &cap);
>> +            IFC_INFO(&dev->dev, "hw->isr = %p.\n", hw->isr);
>> +            break;
>> +        case VIRTIO_PCI_CAP_DEVICE_CFG:
>> +            hw->dev_cfg = get_cap_addr(hw, &cap);
>> +            IFC_INFO(&dev->dev, "hw->dev_cfg = %p.\n", hw->dev_cfg);
>> +            break;
>> +        }
>> +next:
>> +        pos = cap.cap_next;
>> +    }
>> +
>> +    if (hw->common_cfg == NULL || hw->notify_base == NULL ||
>> +        hw->isr == NULL || hw->dev_cfg == NULL) {
>> +        IFC_ERR(&dev->dev, "Incomplete PCI capabilities.\n");
>> +        return -1;
>> +    }
>> +
>> +    for (i = 0; i < (IFCVF_MAX_QUEUE_PAIRS * 2); i++) {
>
>
> Any reason for using hard coded queue pairs limit other than the 
> max_queue_pairs in the net config?
Hi Jason, Thanks for your kindly comments. For now the driver don't 
support MQ, we intend to provide a minimal feature sets in this version 
1 driver.
>
>
>> +        iowrite16(i, &hw->common_cfg->queue_select);
>> +        notify_off = ioread16(&hw->common_cfg->queue_notify_off);
>> +        hw->notify_addr[i] = (void *)((u8 *)hw->notify_base +
>> +                notify_off * hw->notify_off_multiplier);
>> +    }
>> +
>> +    hw->lm_cfg = hw->mem_resource[4].addr;
>> +
>> +    IFC_INFO(&dev->dev, "PCI capability mapping:\n"
>> +                "common cfg: %p\n"
>> +                "notify base: %p\n"
>> +                "isr cfg: %p\n"
>> +                "device cfg: %p\n"
>> +                "multiplier: %u\n",
>> +                hw->common_cfg,
>> +                hw->notify_base,
>> +                hw->isr,
>> +                hw->dev_cfg,
>> +                hw->notify_off_multiplier);
>> +
>> +    return 0;
>> +}
>> +
>> +static u8 ifcvf_get_status(struct ifcvf_hw *hw)
>> +{
>> +    return ioread8(&hw->common_cfg->device_status);
>> +}
>> +
>> +static void ifcvf_set_status(struct ifcvf_hw *hw, u8 status)
>> +{
>> +    iowrite8(status, &hw->common_cfg->device_status);
>> +}
>> +
>> +static void ifcvf_reset(struct ifcvf_hw *hw)
>> +{
>> +    ifcvf_set_status(hw, 0);
>> +
>> +    /* flush status write */
>> +    ifcvf_get_status(hw);
>
>
> Why this flush is needed?

accoring to PCIE requirements, this get_status() after a set_status() is 
used to block the call chain, make sure the hardware has finished the 
write operation.

It is a bad comment anyway, I will remove it.

>
>
>> +    hw->generation++;
>> +}
>> +
>> +static void ifcvf_add_status(struct ifcvf_hw *hw, u8 status)
>> +{
>> +    if (status != 0)
>> +        status |= ifcvf_get_status(hw);
>> +
>> +    ifcvf_set_status(hw, status);
>> +    ifcvf_get_status(hw);
>> +}
>> +
>> +u64 ifcvf_get_features(struct ifcvf_hw *hw)
>> +{
>> +    u32 features_lo, features_hi;
>> +    struct virtio_pci_common_cfg *cfg = hw->common_cfg;
>> +
>> +    iowrite32(0, &cfg->device_feature_select);
>> +    features_lo = ioread32(&cfg->device_feature);
>> +
>> +    iowrite32(1, &cfg->device_feature_select);
>> +    features_hi = ioread32(&cfg->device_feature);
>> +
>> +    return ((u64)features_hi << 32) | features_lo;
>> +}
>> +static int ifcvf_with_feature(struct ifcvf_hw *hw, u64 bit)
>> +{
>> +    return (hw->req_features & (1ULL << bit)) != 0;
>> +}
>> +
>> +static void ifcvf_read_dev_config(struct ifcvf_hw *hw, u64 offset,
>> +               void *dst, int length)
>> +{
>> +    int i;
>> +    u8 *p;
>> +    u8 old_gen, new_gen;
>> +
>> +    do {
>> +        old_gen = ioread8(&hw->common_cfg->config_generation);
>> +
>> +        p = dst;
>> +        for (i = 0; i < length; i++)
>> +            *p++ = ioread8((u8 *)hw->dev_cfg + offset + i);
>> +
>> +        new_gen = ioread8(&hw->common_cfg->config_generation);
>> +    } while (old_gen != new_gen);
>> +}
>> +
>> +void ifcvf_get_linkstatus(struct ifcvf_hw *hw, u8 *is_linkup)
>> +{
>
>
> Why not just return bollean?
sure, can do.
>
>
>> +    u16 status;
>> +    u64 host_features;
>> +
>> +    host_features = ifcvf_get_features(hw);
>> +    if (ifcvf_with_feature(hw, VIRTIO_NET_F_STATUS)) {
>> +        ifcvf_read_dev_config(hw,
>> +                offsetof(struct ifcvf_net_config, status),
>> +                &status, sizeof(status));
>> +        if ((status & VIRTIO_NET_S_LINK_UP) == 0)
>> +            (*is_linkup) = 1;
>> +        else
>> +            (*is_linkup) = 0;
>> +    } else
>> +        (*is_linkup) = 0;
>> +}
>> +
>> +static void ifcvf_set_features(struct ifcvf_hw *hw, u64 features)
>> +{
>> +    struct virtio_pci_common_cfg *cfg = hw->common_cfg;
>> +
>> +    iowrite32(0, &cfg->guest_feature_select);
>> +    iowrite32(features & ((1ULL << 32) - 1), &cfg->guest_feature);
>> +
>> +    iowrite32(1, &cfg->guest_feature_select);
>> +    iowrite32(features >> 32, &cfg->guest_feature);
>> +}
>> +
>> +static int ifcvf_config_features(struct ifcvf_hw *hw)
>> +{
>> +    u64 host_features;
>> +    struct ifcvf_adapter *ifcvf =
>> +        container_of(hw, struct ifcvf_adapter, vf);
>> +
>> +    host_features = ifcvf_get_features(hw);
>> +    hw->req_features &= host_features;
>
>
> Is this a must, can't device deal with this?
I will usehw->req_features directly, thanks for point it out.
>
>
>> +
>> +    ifcvf_set_features(hw, hw->req_features);
>> +    ifcvf_add_status(hw, VIRTIO_CONFIG_S_FEATURES_OK);
>> +
>> +    if (!(ifcvf_get_status(hw) & VIRTIO_CONFIG_S_FEATURES_OK)) {
>> +        IFC_ERR(ifcvf->dev, "Failed to set FEATURES_OK status\n");
>> +        return -EIO;
>> +    }
>> +
>> +    return 0;
>> +}
>> +
>> +static void io_write64_twopart(u64 val, u32 *lo, u32 *hi)
>> +{
>> +    iowrite32(val & ((1ULL << 32) - 1), lo);
>> +    iowrite32(val >> 32, hi);
>> +}
>> +
>> +static int ifcvf_hw_enable(struct ifcvf_hw *hw)
>> +{
>> +    struct virtio_pci_common_cfg *cfg;
>> +    u8 *lm_cfg;
>> +    u32 i;
>> +    struct ifcvf_adapter *ifcvf =
>> +        container_of(hw, struct ifcvf_adapter, vf);
>> +
>> +    cfg = hw->common_cfg;
>> +    lm_cfg = hw->lm_cfg;
>> +
>> +    iowrite16(IFCVF_MSI_CONFIG_OFF, &cfg->msix_config);
>> +    if (ioread16(&cfg->msix_config) == VIRTIO_MSI_NO_VECTOR) {
>> +        IFC_ERR(ifcvf->dev, "No msix vector for device config.\n");
>> +        return -1;
>> +    }
>> +
>> +    for (i = 0; i < hw->nr_vring; i++) {
>> +        iowrite16(i, &cfg->queue_select);
>> +        io_write64_twopart(hw->vring[i].desc, &cfg->queue_desc_lo,
>> +                &cfg->queue_desc_hi);
>> +        io_write64_twopart(hw->vring[i].avail, &cfg->queue_avail_lo,
>> +                &cfg->queue_avail_hi);
>> +        io_write64_twopart(hw->vring[i].used, &cfg->queue_used_lo,
>> +                &cfg->queue_used_hi);
>> +        iowrite16(hw->vring[i].size, &cfg->queue_size);
>> +
>> +        *(u32 *)(lm_cfg + IFCVF_LM_RING_STATE_OFFSET +
>> +                (i / 2) * IFCVF_LM_CFG_SIZE + (i % 2) * 4) =
>> +            (u32)hw->vring[i].last_avail_idx |
>> +            ((u32)hw->vring[i].last_used_idx << 16);
>> +
>> +        iowrite16(i + IFCVF_MSI_QUEUE_OFF, &cfg->queue_msix_vector);
>> +        if (ioread16(&cfg->queue_msix_vector) ==
>> +                VIRTIO_MSI_NO_VECTOR) {
>> +            IFC_ERR(ifcvf->dev,
>> +                "No msix vector for queue %u.\n", i);
>> +            return -1;
>> +        }
>> +
>> +        iowrite16(1, &cfg->queue_enable);
>> +    }
>> +
>> +    return 0;
>> +}
>> +
>> +static void ifcvf_hw_disable(struct ifcvf_hw *hw)
>> +{
>> +    u32 i;
>> +    struct virtio_pci_common_cfg *cfg;
>> +
>> +    cfg = hw->common_cfg;
>> +
>> +    iowrite16(VIRTIO_MSI_NO_VECTOR, &cfg->msix_config);
>> +    for (i = 0; i < hw->nr_vring; i++) {
>> +        iowrite16(i, &cfg->queue_select);
>> +        iowrite16(0, &cfg->queue_enable);
>> +        iowrite16(VIRTIO_MSI_NO_VECTOR, &cfg->queue_msix_vector);
>> +    }
>> +}
>> +
>> +int ifcvf_start_hw(struct ifcvf_hw *hw)
>> +{
>> +    ifcvf_reset(hw);
>> +    ifcvf_add_status(hw, VIRTIO_CONFIG_S_ACKNOWLEDGE);
>> +    ifcvf_add_status(hw, VIRTIO_CONFIG_S_DRIVER);
>> +
>> +    if (ifcvf_config_features(hw) < 0)
>> +        return -1;
>> +
>> +    if (ifcvf_hw_enable(hw) < 0)
>> +        return -1;
>> +
>> +    ifcvf_add_status(hw, VIRTIO_CONFIG_S_DRIVER_OK);
>> +
>> +    return 0;
>> +}
>> +
>> +void ifcvf_stop_hw(struct ifcvf_hw *hw)
>> +{
>> +    ifcvf_hw_disable(hw);
>> +    ifcvf_reset(hw);
>> +}
>> +
>> +void ifcvf_enable_logging_vf(struct ifcvf_hw *hw, u64 log_base, u64 
>> log_size)
>> +{
>> +    u8 *lm_cfg;
>> +
>> +    lm_cfg = hw->lm_cfg;
>> +
>> +    *(u32 *)(lm_cfg + IFCVF_LM_BASE_ADDR_LOW) =
>> +        log_base & IFCVF_32_BIT_MASK;
>> +
>> +    *(u32 *)(lm_cfg + IFCVF_LM_BASE_ADDR_HIGH) =
>> +        (log_base >> 32) & IFCVF_32_BIT_MASK;
>> +
>> +    *(u32 *)(lm_cfg + IFCVF_LM_END_ADDR_LOW) =
>> +        (log_base + log_size) & IFCVF_32_BIT_MASK;
>> +
>> +    *(u32 *)(lm_cfg + IFCVF_LM_END_ADDR_HIGH) =
>> +        ((log_base + log_size) >> 32) & IFCVF_32_BIT_MASK;
>> +
>> +    *(u32 *)(lm_cfg + IFCVF_LM_LOGGING_CTRL) = IFCVF_LM_ENABLE_VF;
>> +}
>
>
> Is the device using iova or gpa for the logging?
gpa, I will remove all LM related functions since we plan to support LM 
in next version driver.
>
>
>> +
>> +void ifcvf_disable_logging(struct ifcvf_hw *hw)
>> +{
>> +    u8 *lm_cfg;
>> +
>> +    lm_cfg = hw->lm_cfg;
>> +    *(u32 *)(lm_cfg + IFCVF_LM_LOGGING_CTRL) = IFCVF_LM_DISABLE;
>> +}
>> +
>> +void ifcvf_notify_queue(struct ifcvf_hw *hw, u16 qid)
>> +{
>> +
>> +    iowrite16(qid, hw->notify_addr[qid]);
>> +}
>> +
>> +u8 ifcvf_get_notify_region(struct ifcvf_hw *hw)
>> +{
>> +    return hw->notify_bar;
>> +}
>> +
>> +u64 ifcvf_get_queue_notify_off(struct ifcvf_hw *hw, int qid)
>> +{
>> +    return (u8 *)hw->notify_addr[qid] -
>> +        (u8 *)hw->mem_resource[hw->notify_bar].addr;
>> +}
>> diff --git a/drivers/vhost/ifcvf/ifcvf_base.h 
>> b/drivers/vhost/ifcvf/ifcvf_base.h
>> new file mode 100644
>> index 000000000000..1ab1a1c40f24
>> --- /dev/null
>> +++ b/drivers/vhost/ifcvf/ifcvf_base.h
>> @@ -0,0 +1,137 @@
>> +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
>> +/*
>> + * Copyright (C) 2019 Intel Corporation.
>> + */
>> +
>> +#ifndef _IFCVF_H_
>> +#define _IFCVF_H_
>> +
>> +#include <linux/virtio_mdev.h>
>> +#include <linux/pci.h>
>> +#include <linux/pci_regs.h>
>> +#include <uapi/linux/virtio_net.h>
>> +#include <uapi/linux/virtio_config.h>
>> +#include <uapi/linux/virtio_pci.h>
>> +
>> +#define IFCVF_VENDOR_ID         0x1AF4
>> +#define IFCVF_DEVICE_ID         0x1041
>> +#define IFCVF_SUBSYS_VENDOR_ID  0x8086
>> +#define IFCVF_SUBSYS_DEVICE_ID  0x001A
>> +
>> +/*
>> + * Some ifcvf feature bits (currently bits 28 through 31) are
>> + * reserved for the transport being used (eg. ifcvf_ring), the
>> + * rest are per-device feature bits.
>> + */
>> +#define IFCVF_TRANSPORT_F_START 28
>> +#define IFCVF_TRANSPORT_F_END   34
>> +
>> +#define IFC_SUPPORTED_FEATURES \
>> +        ((1ULL << VIRTIO_NET_F_MAC)            | \
>> +         (1ULL << VIRTIO_F_ANY_LAYOUT)            | \
>> +         (1ULL << VIRTIO_F_VERSION_1) | \
>> +         (1ULL << VHOST_F_LOG_ALL)            | \
>> +         (1ULL << VIRTIO_NET_F_GUEST_ANNOUNCE)        | \
>> +         (1ULL << VIRTIO_NET_F_CTRL_VQ)            | \
>> +         (1ULL << VIRTIO_NET_F_STATUS)            | \
>> +         (1ULL << VIRTIO_NET_F_MRG_RXBUF)) /* not fully supported */
>> +
>> +#define IFCVF_MAX_QUEUE_PAIRS        1
>> +#define IFCVF_MAX_QUEUES        2
>> +
>> +#define IFCVF_QUEUE_ALIGNMENT        PAGE_SIZE
>> +
>> +#define IFCVF_MSI_CONFIG_OFF    0
>> +#define IFCVF_MSI_QUEUE_OFF    1
>> +#define IFCVF_PCI_MAX_RESOURCE    6
>> +
>> +/* 46 bit CPU physical address, avoid overlap */
>> +#define LM_IOVA 0x400000000000
>> +
>> +#define IFCVF_LM_CFG_SIZE        0x40
>> +#define IFCVF_LM_RING_STATE_OFFSET    0x20
>> +
>> +#define IFCVF_LM_LOGGING_CTRL        0x0
>> +
>> +#define IFCVF_LM_BASE_ADDR_LOW        0x10
>> +#define IFCVF_LM_BASE_ADDR_HIGH        0x14
>> +#define IFCVF_LM_END_ADDR_LOW        0x18
>> +#define IFCVF_LM_END_ADDR_HIGH        0x1c
>> +
>> +#define IFCVF_LM_DISABLE        0x0
>> +#define IFCVF_LM_ENABLE_VF        0x1
>> +#define IFCVF_LM_ENABLE_PF        0x3
>> +
>> +#define IFCVF_32_BIT_MASK        0xffffffff
>> +
>> +#define IFC_ERR(dev, fmt, ...)    dev_err(dev, fmt, ##__VA_ARGS__)
>> +#define IFC_INFO(dev, fmt, ...)    dev_info(dev, fmt, ##__VA_ARGS__)
>> +
>> +struct ifcvf_net_config {
>> +    u8    mac[6];
>> +    u16   status;
>> +    u16   max_virtqueue_pairs;
>> +} __packed;
>> +
>> +struct ifcvf_pci_mem_resource {
>> +    u64      phys_addr; /**< Physical address, 0 if not resource. */
>> +    u64      len;       /**< Length of the resource. */
>> +    u8       *addr;     /**< Virtual address, NULL when not mapped. */
>> +};
>> +
>> +struct vring_info {
>> +    u64 desc;
>> +    u64 avail;
>> +    u64 used;
>> +    u16 size;
>> +    u16 last_avail_idx;
>> +    u16 last_used_idx;
>> +    bool ready;
>> +    char msix_name[256];
>> +    struct virtio_mdev_callback cb;
>> +};
>> +
>> +struct ifcvf_hw {
>> +    u8    *isr;
>> +    u8    notify_bar;
>> +    u8    *lm_cfg;
>> +    u8    status;
>> +    u8    nr_vring;
>
>
> Is the the number of queue currently used?
Do you mean nr_vring? Yes it is used in hardware enable / disable functions.
>
>
>> +    u16    *notify_base;
>> +    u16    *notify_addr[IFCVF_MAX_QUEUE_PAIRS * 2];
>> +    u32    generation;
>> +    u32    notify_off_multiplier;
>> +    u64    req_features;
>> +    struct    virtio_pci_common_cfg *common_cfg;
>> +    struct    ifcvf_net_config *dev_cfg;
>> +    struct    vring_info vring[IFCVF_MAX_QUEUE_PAIRS * 2];
>> +    struct    ifcvf_pci_mem_resource 
>> mem_resource[IFCVF_PCI_MAX_RESOURCE];
>> +};
>> +
>> +#define IFC_PRIVATE_TO_VF(adapter) \
>> +    (&((struct ifcvf_adapter *)adapter)->vf)
>> +
>> +#define IFCVF_MAX_INTR (IFCVF_MAX_QUEUE_PAIRS * 2 + 1)
>
>
> The extra one means the config interrupt?
Yes.
>
>
>> +
>> +struct ifcvf_adapter {
>> +    struct    device *dev;
>> +    struct    mutex mdev_lock;
>
>
> Not used in the patch, move to next one?
Sure, these not used ones will be moved to small patches where they are 
used in v1 patchset.
>
>
>> +    int    mdev_count;
>
>
> Not used.
>
>
>> +    struct    list_head dma_maps;
>
>
> This is not used.
>
> Thanks
>
>
>> +    int    vectors;
>> +    struct    ifcvf_hw vf;
>> +};
>> +
>> +int ifcvf_init_hw(struct ifcvf_hw *hw, struct pci_dev *dev);
>> +u64 ifcvf_get_features(struct ifcvf_hw *hw);
>> +int ifcvf_start_hw(struct ifcvf_hw *hw);
>> +void ifcvf_stop_hw(struct ifcvf_hw *hw);
>> +void ifcvf_enable_logging(struct ifcvf_hw *hw, u64 log_base, u64 
>> log_size);
>> +void ifcvf_enable_logging_vf(struct ifcvf_hw *hw, u64 log_base, u64 
>> log_size);
>> +void ifcvf_disable_logging(struct ifcvf_hw *hw);
>> +void ifcvf_notify_queue(struct ifcvf_hw *hw, u16 qid);
>> +void ifcvf_get_linkstatus(struct ifcvf_hw *hw, u8 *is_linkup);
>> +u8 ifcvf_get_notify_region(struct ifcvf_hw *hw);
>> +u64 ifcvf_get_queue_notify_off(struct ifcvf_hw *hw, int qid);
>> +
>> +#endif /* _IFCVF_H_ */

Re: [RFC 1/2] vhost: IFC VF hardware operation layer

[Zhu, Lingshan]

On 10/16/2019 4:45 PM, Jason Wang wrote:
>
> On 2019/10/16 上午9:30, Zhu Lingshan wrote:
>> + */
>> +#define IFCVF_TRANSPORT_F_START 28
>> +#define IFCVF_TRANSPORT_F_END   34
>> +
>> +#define IFC_SUPPORTED_FEATURES \
>> +        ((1ULL << VIRTIO_NET_F_MAC)            | \
>> +         (1ULL << VIRTIO_F_ANY_LAYOUT)            | \
>> +         (1ULL << VIRTIO_F_VERSION_1) | \
>> +         (1ULL << VHOST_F_LOG_ALL)            | \
>
>
> Let's avoid using VHOST_F_LOG_ALL, using the get_mdev_features() instead.
Thanks, I will remove VHOST_F_LOG_ALL
>
>
>> +         (1ULL << VIRTIO_NET_F_GUEST_ANNOUNCE)        | \
>> +         (1ULL << VIRTIO_NET_F_CTRL_VQ)            | \
>> +         (1ULL << VIRTIO_NET_F_STATUS)            | \
>> +         (1ULL << VIRTIO_NET_F_MRG_RXBUF)) /* not fully supported */
>
>
> Why not having VIRTIO_F_IOMMU_PLATFORM and VIRTIO_F_ORDER_PLATFORM?

I will add VIRTIO_F_ORDER_PLATFORM, for VIRTIO_F_IOMMU_PLATFORM, if we 
add this bit, QEMU may enable viommu, can cause troubles in LM (through 
we don't support LM in this version driver)

Thanks,
BR
Zhu Lingshan
>
> Thanks
>

Re: [RFC 1/2] vhost: IFC VF hardware operation layer

[Jason Wang]

On 2019/10/16 上午9:30, Zhu Lingshan wrote:
> + */
> +#define IFCVF_TRANSPORT_F_START 28
> +#define IFCVF_TRANSPORT_F_END   34
> +
> +#define IFC_SUPPORTED_FEATURES \
> +		((1ULL << VIRTIO_NET_F_MAC)			| \
> +		 (1ULL << VIRTIO_F_ANY_LAYOUT)			| \
> +		 (1ULL << VIRTIO_F_VERSION_1)			| \
> +		 (1ULL << VHOST_F_LOG_ALL)			| \


Let's avoid using VHOST_F_LOG_ALL, using the get_mdev_features() instead.


> +		 (1ULL << VIRTIO_NET_F_GUEST_ANNOUNCE)		| \
> +		 (1ULL << VIRTIO_NET_F_CTRL_VQ)			| \
> +		 (1ULL << VIRTIO_NET_F_STATUS)			| \
> +		 (1ULL << VIRTIO_NET_F_MRG_RXBUF)) /* not fully supported */


Why not having VIRTIO_F_IOMMU_PLATFORM and VIRTIO_F_ORDER_PLATFORM?

Thanks

Re: [RFC 1/2] vhost: IFC VF hardware operation layer

[Jason Wang]

On 2019/10/16 上午9:30, Zhu Lingshan wrote:
> This commit introduced ifcvf_base layer, which handles IFC VF NIC
> hardware operations and configurations.


It's better to describe the difference between ifc vf and virtio in the 
commit log or is there a open doc for this?


>
> Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
> ---
>   drivers/vhost/ifcvf/ifcvf_base.c | 390 +++++++++++++++++++++++++++++++++++++++
>   drivers/vhost/ifcvf/ifcvf_base.h | 137 ++++++++++++++
>   2 files changed, 527 insertions(+)
>   create mode 100644 drivers/vhost/ifcvf/ifcvf_base.c
>   create mode 100644 drivers/vhost/ifcvf/ifcvf_base.h
>
> diff --git a/drivers/vhost/ifcvf/ifcvf_base.c b/drivers/vhost/ifcvf/ifcvf_base.c
> new file mode 100644
> index 000000000000..b85e14c9bdcf
> --- /dev/null
> +++ b/drivers/vhost/ifcvf/ifcvf_base.c
> @@ -0,0 +1,390 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (C) 2019 Intel Corporation.
> + */
> +
> +#include "ifcvf_base.h"
> +
> +static void *get_cap_addr(struct ifcvf_hw *hw, struct virtio_pci_cap *cap)
> +{
> +	u8 bar = cap->bar;
> +	u32 length = cap->length;
> +	u32 offset = cap->offset;
> +	struct ifcvf_adapter *ifcvf =
> +		container_of(hw, struct ifcvf_adapter, vf);
> +
> +	if (bar >= IFCVF_PCI_MAX_RESOURCE) {
> +		IFC_ERR(ifcvf->dev,
> +			"Invalid bar number %u to get capabilities.\n", bar);
> +		return NULL;
> +	}
> +
> +	if (offset + length < offset) {
> +		IFC_ERR(ifcvf->dev, "offset(%u) + length(%u) overflows\n",
> +			offset, length);
> +		return NULL;
> +	}
> +
> +	if (offset + length > hw->mem_resource[cap->bar].len) {
> +		IFC_ERR(ifcvf->dev,
> +			"offset(%u) + len(%u) overflows bar%u to get capabilities.\n",
> +			offset, length, bar);
> +		return NULL;
> +	}
> +
> +	return hw->mem_resource[bar].addr + offset;
> +}
> +
> +int ifcvf_read_config_range(struct pci_dev *dev,
> +			uint32_t *val, int size, int where)
> +{
> +	int i;
> +
> +	for (i = 0; i < size; i += 4) {
> +		if (pci_read_config_dword(dev, where + i, val + i / 4) < 0)
> +			return -1;
> +	}
> +	return 0;
> +}
> +
> +int ifcvf_init_hw(struct ifcvf_hw *hw, struct pci_dev *dev)
> +{
> +	int ret;
> +	u8 pos;
> +	struct virtio_pci_cap cap;
> +	u32 i;
> +	u16 notify_off;
> +
> +	ret = pci_read_config_byte(dev, PCI_CAPABILITY_LIST, &pos);
> +
> +	if (ret < 0) {
> +		IFC_ERR(&dev->dev, "failed to read PCI capability list.\n");
> +		return -EIO;
> +	}
> +
> +	while (pos) {
> +		ret = ifcvf_read_config_range(dev, (u32 *)&cap,
> +				sizeof(cap), pos);
> +
> +		if (ret < 0) {
> +			IFC_ERR(&dev->dev, "failed to get PCI capability at %x",
> +					pos);
> +			break;
> +		}
> +
> +		if (cap.cap_vndr != PCI_CAP_ID_VNDR)
> +			goto next;
> +
> +		IFC_INFO(&dev->dev, "read PCI config:\n"
> +					"config type: %u.\n"
> +					"PCI bar: %u.\n"
> +					"PCI bar offset: %u.\n"
> +					"PCI config len: %u.\n",
> +					cap.cfg_type, cap.bar,
> +					cap.offset, cap.length);
> +
> +		switch (cap.cfg_type) {
> +		case VIRTIO_PCI_CAP_COMMON_CFG:
> +			hw->common_cfg = get_cap_addr(hw, &cap);
> +			IFC_INFO(&dev->dev, "hw->common_cfg = %p.\n",
> +					hw->common_cfg);
> +			break;
> +		case VIRTIO_PCI_CAP_NOTIFY_CFG:
> +			pci_read_config_dword(dev, pos + sizeof(cap),
> +				&hw->notify_off_multiplier);
> +			hw->notify_bar = cap.bar;
> +			hw->notify_base = get_cap_addr(hw, &cap);
> +			IFC_INFO(&dev->dev, "hw->notify_base = %p.\n",
> +					hw->notify_base);
> +			break;
> +		case VIRTIO_PCI_CAP_ISR_CFG:
> +			hw->isr = get_cap_addr(hw, &cap);
> +			IFC_INFO(&dev->dev, "hw->isr = %p.\n", hw->isr);
> +			break;
> +		case VIRTIO_PCI_CAP_DEVICE_CFG:
> +			hw->dev_cfg = get_cap_addr(hw, &cap);
> +			IFC_INFO(&dev->dev, "hw->dev_cfg = %p.\n", hw->dev_cfg);
> +			break;
> +		}
> +next:
> +		pos = cap.cap_next;
> +	}
> +
> +	if (hw->common_cfg == NULL || hw->notify_base == NULL ||
> +		hw->isr == NULL || hw->dev_cfg == NULL) {
> +		IFC_ERR(&dev->dev, "Incomplete PCI capabilities.\n");
> +		return -1;
> +	}
> +
> +	for (i = 0; i < (IFCVF_MAX_QUEUE_PAIRS * 2); i++) {


Any reason for using hard coded queue pairs limit other than the 
max_queue_pairs in the net config?


> +		iowrite16(i, &hw->common_cfg->queue_select);
> +		notify_off = ioread16(&hw->common_cfg->queue_notify_off);
> +		hw->notify_addr[i] = (void *)((u8 *)hw->notify_base +
> +				notify_off * hw->notify_off_multiplier);
> +	}
> +
> +	hw->lm_cfg = hw->mem_resource[4].addr;
> +
> +	IFC_INFO(&dev->dev, "PCI capability mapping:\n"
> +				"common cfg: %p\n"
> +				"notify base: %p\n"
> +				"isr cfg: %p\n"
> +				"device cfg: %p\n"
> +				"multiplier: %u\n",
> +				hw->common_cfg,
> +				hw->notify_base,
> +				hw->isr,
> +				hw->dev_cfg,
> +				hw->notify_off_multiplier);
> +
> +	return 0;
> +}
> +
> +static u8 ifcvf_get_status(struct ifcvf_hw *hw)
> +{
> +	return ioread8(&hw->common_cfg->device_status);
> +}
> +
> +static void ifcvf_set_status(struct ifcvf_hw *hw, u8 status)
> +{
> +	iowrite8(status, &hw->common_cfg->device_status);
> +}
> +
> +static void ifcvf_reset(struct ifcvf_hw *hw)
> +{
> +	ifcvf_set_status(hw, 0);
> +
> +	/* flush status write */
> +	ifcvf_get_status(hw);


Why this flush is needed?


> +	hw->generation++;
> +}
> +
> +static void ifcvf_add_status(struct ifcvf_hw *hw, u8 status)
> +{
> +	if (status != 0)
> +		status |= ifcvf_get_status(hw);
> +
> +	ifcvf_set_status(hw, status);
> +	ifcvf_get_status(hw);
> +}
> +
> +u64 ifcvf_get_features(struct ifcvf_hw *hw)
> +{
> +	u32 features_lo, features_hi;
> +	struct virtio_pci_common_cfg *cfg = hw->common_cfg;
> +
> +	iowrite32(0, &cfg->device_feature_select);
> +	features_lo = ioread32(&cfg->device_feature);
> +
> +	iowrite32(1, &cfg->device_feature_select);
> +	features_hi = ioread32(&cfg->device_feature);
> +
> +	return ((u64)features_hi << 32) | features_lo;
> +}
> +static int ifcvf_with_feature(struct ifcvf_hw *hw, u64 bit)
> +{
> +	return (hw->req_features & (1ULL << bit)) != 0;
> +}
> +
> +static void ifcvf_read_dev_config(struct ifcvf_hw *hw, u64 offset,
> +		       void *dst, int length)
> +{
> +	int i;
> +	u8 *p;
> +	u8 old_gen, new_gen;
> +
> +	do {
> +		old_gen = ioread8(&hw->common_cfg->config_generation);
> +
> +		p = dst;
> +		for (i = 0; i < length; i++)
> +			*p++ = ioread8((u8 *)hw->dev_cfg + offset + i);
> +
> +		new_gen = ioread8(&hw->common_cfg->config_generation);
> +	} while (old_gen != new_gen);
> +}
> +
> +void ifcvf_get_linkstatus(struct ifcvf_hw *hw, u8 *is_linkup)
> +{


Why not just return bollean?


> +	u16 status;
> +	u64 host_features;
> +
> +	host_features = ifcvf_get_features(hw);
> +	if (ifcvf_with_feature(hw, VIRTIO_NET_F_STATUS)) {
> +		ifcvf_read_dev_config(hw,
> +				offsetof(struct ifcvf_net_config, status),
> +				&status, sizeof(status));
> +		if ((status & VIRTIO_NET_S_LINK_UP) == 0)
> +			(*is_linkup) = 1;
> +		else
> +			(*is_linkup) = 0;
> +	} else
> +		(*is_linkup) = 0;
> +}
> +
> +static void ifcvf_set_features(struct ifcvf_hw *hw, u64 features)
> +{
> +	struct virtio_pci_common_cfg *cfg = hw->common_cfg;
> +
> +	iowrite32(0, &cfg->guest_feature_select);
> +	iowrite32(features & ((1ULL << 32) - 1), &cfg->guest_feature);
> +
> +	iowrite32(1, &cfg->guest_feature_select);
> +	iowrite32(features >> 32, &cfg->guest_feature);
> +}
> +
> +static int ifcvf_config_features(struct ifcvf_hw *hw)
> +{
> +	u64 host_features;
> +	struct ifcvf_adapter *ifcvf =
> +		container_of(hw, struct ifcvf_adapter, vf);
> +
> +	host_features = ifcvf_get_features(hw);
> +	hw->req_features &= host_features;


Is this a must, can't device deal with this?


> +
> +	ifcvf_set_features(hw, hw->req_features);
> +	ifcvf_add_status(hw, VIRTIO_CONFIG_S_FEATURES_OK);
> +
> +	if (!(ifcvf_get_status(hw) & VIRTIO_CONFIG_S_FEATURES_OK)) {
> +		IFC_ERR(ifcvf->dev, "Failed to set FEATURES_OK status\n");
> +		return -EIO;
> +	}
> +
> +	return 0;
> +}
> +
> +static void io_write64_twopart(u64 val, u32 *lo, u32 *hi)
> +{
> +	iowrite32(val & ((1ULL << 32) - 1), lo);
> +	iowrite32(val >> 32, hi);
> +}
> +
> +static int ifcvf_hw_enable(struct ifcvf_hw *hw)
> +{
> +	struct virtio_pci_common_cfg *cfg;
> +	u8 *lm_cfg;
> +	u32 i;
> +	struct ifcvf_adapter *ifcvf =
> +		container_of(hw, struct ifcvf_adapter, vf);
> +
> +	cfg = hw->common_cfg;
> +	lm_cfg = hw->lm_cfg;
> +
> +	iowrite16(IFCVF_MSI_CONFIG_OFF, &cfg->msix_config);
> +	if (ioread16(&cfg->msix_config) == VIRTIO_MSI_NO_VECTOR) {
> +		IFC_ERR(ifcvf->dev, "No msix vector for device config.\n");
> +		return -1;
> +	}
> +
> +	for (i = 0; i < hw->nr_vring; i++) {
> +		iowrite16(i, &cfg->queue_select);
> +		io_write64_twopart(hw->vring[i].desc, &cfg->queue_desc_lo,
> +				&cfg->queue_desc_hi);
> +		io_write64_twopart(hw->vring[i].avail, &cfg->queue_avail_lo,
> +				&cfg->queue_avail_hi);
> +		io_write64_twopart(hw->vring[i].used, &cfg->queue_used_lo,
> +				&cfg->queue_used_hi);
> +		iowrite16(hw->vring[i].size, &cfg->queue_size);
> +
> +		*(u32 *)(lm_cfg + IFCVF_LM_RING_STATE_OFFSET +
> +				(i / 2) * IFCVF_LM_CFG_SIZE + (i % 2) * 4) =
> +			(u32)hw->vring[i].last_avail_idx |
> +			((u32)hw->vring[i].last_used_idx << 16);
> +
> +		iowrite16(i + IFCVF_MSI_QUEUE_OFF, &cfg->queue_msix_vector);
> +		if (ioread16(&cfg->queue_msix_vector) ==
> +				VIRTIO_MSI_NO_VECTOR) {
> +			IFC_ERR(ifcvf->dev,
> +				"No msix vector for queue %u.\n", i);
> +			return -1;
> +		}
> +
> +		iowrite16(1, &cfg->queue_enable);
> +	}
> +
> +	return 0;
> +}
> +
> +static void ifcvf_hw_disable(struct ifcvf_hw *hw)
> +{
> +	u32 i;
> +	struct virtio_pci_common_cfg *cfg;
> +
> +	cfg = hw->common_cfg;
> +
> +	iowrite16(VIRTIO_MSI_NO_VECTOR, &cfg->msix_config);
> +	for (i = 0; i < hw->nr_vring; i++) {
> +		iowrite16(i, &cfg->queue_select);
> +		iowrite16(0, &cfg->queue_enable);
> +		iowrite16(VIRTIO_MSI_NO_VECTOR, &cfg->queue_msix_vector);
> +	}
> +}
> +
> +int ifcvf_start_hw(struct ifcvf_hw *hw)
> +{
> +	ifcvf_reset(hw);
> +	ifcvf_add_status(hw, VIRTIO_CONFIG_S_ACKNOWLEDGE);
> +	ifcvf_add_status(hw, VIRTIO_CONFIG_S_DRIVER);
> +
> +	if (ifcvf_config_features(hw) < 0)
> +		return -1;
> +
> +	if (ifcvf_hw_enable(hw) < 0)
> +		return -1;
> +
> +	ifcvf_add_status(hw, VIRTIO_CONFIG_S_DRIVER_OK);
> +
> +	return 0;
> +}
> +
> +void ifcvf_stop_hw(struct ifcvf_hw *hw)
> +{
> +	ifcvf_hw_disable(hw);
> +	ifcvf_reset(hw);
> +}
> +
> +void ifcvf_enable_logging_vf(struct ifcvf_hw *hw, u64 log_base, u64 log_size)
> +{
> +	u8 *lm_cfg;
> +
> +	lm_cfg = hw->lm_cfg;
> +
> +	*(u32 *)(lm_cfg + IFCVF_LM_BASE_ADDR_LOW) =
> +		log_base & IFCVF_32_BIT_MASK;
> +
> +	*(u32 *)(lm_cfg + IFCVF_LM_BASE_ADDR_HIGH) =
> +		(log_base >> 32) & IFCVF_32_BIT_MASK;
> +
> +	*(u32 *)(lm_cfg + IFCVF_LM_END_ADDR_LOW) =
> +		(log_base + log_size) & IFCVF_32_BIT_MASK;
> +
> +	*(u32 *)(lm_cfg + IFCVF_LM_END_ADDR_HIGH) =
> +		((log_base + log_size) >> 32) & IFCVF_32_BIT_MASK;
> +
> +	*(u32 *)(lm_cfg + IFCVF_LM_LOGGING_CTRL) = IFCVF_LM_ENABLE_VF;
> +}


Is the device using iova or gpa for the logging?


> +
> +void ifcvf_disable_logging(struct ifcvf_hw *hw)
> +{
> +	u8 *lm_cfg;
> +
> +	lm_cfg = hw->lm_cfg;
> +	*(u32 *)(lm_cfg + IFCVF_LM_LOGGING_CTRL) = IFCVF_LM_DISABLE;
> +}
> +
> +void ifcvf_notify_queue(struct ifcvf_hw *hw, u16 qid)
> +{
> +
> +	iowrite16(qid, hw->notify_addr[qid]);
> +}
> +
> +u8 ifcvf_get_notify_region(struct ifcvf_hw *hw)
> +{
> +	return hw->notify_bar;
> +}
> +
> +u64 ifcvf_get_queue_notify_off(struct ifcvf_hw *hw, int qid)
> +{
> +	return (u8 *)hw->notify_addr[qid] -
> +		(u8 *)hw->mem_resource[hw->notify_bar].addr;
> +}
> diff --git a/drivers/vhost/ifcvf/ifcvf_base.h b/drivers/vhost/ifcvf/ifcvf_base.h
> new file mode 100644
> index 000000000000..1ab1a1c40f24
> --- /dev/null
> +++ b/drivers/vhost/ifcvf/ifcvf_base.h
> @@ -0,0 +1,137 @@
> +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
> +/*
> + * Copyright (C) 2019 Intel Corporation.
> + */
> +
> +#ifndef _IFCVF_H_
> +#define _IFCVF_H_
> +
> +#include <linux/virtio_mdev.h>
> +#include <linux/pci.h>
> +#include <linux/pci_regs.h>
> +#include <uapi/linux/virtio_net.h>
> +#include <uapi/linux/virtio_config.h>
> +#include <uapi/linux/virtio_pci.h>
> +
> +#define IFCVF_VENDOR_ID         0x1AF4
> +#define IFCVF_DEVICE_ID         0x1041
> +#define IFCVF_SUBSYS_VENDOR_ID  0x8086
> +#define IFCVF_SUBSYS_DEVICE_ID  0x001A
> +
> +/*
> + * Some ifcvf feature bits (currently bits 28 through 31) are
> + * reserved for the transport being used (eg. ifcvf_ring), the
> + * rest are per-device feature bits.
> + */
> +#define IFCVF_TRANSPORT_F_START 28
> +#define IFCVF_TRANSPORT_F_END   34
> +
> +#define IFC_SUPPORTED_FEATURES \
> +		((1ULL << VIRTIO_NET_F_MAC)			| \
> +		 (1ULL << VIRTIO_F_ANY_LAYOUT)			| \
> +		 (1ULL << VIRTIO_F_VERSION_1)			| \
> +		 (1ULL << VHOST_F_LOG_ALL)			| \
> +		 (1ULL << VIRTIO_NET_F_GUEST_ANNOUNCE)		| \
> +		 (1ULL << VIRTIO_NET_F_CTRL_VQ)			| \
> +		 (1ULL << VIRTIO_NET_F_STATUS)			| \
> +		 (1ULL << VIRTIO_NET_F_MRG_RXBUF)) /* not fully supported */
> +
> +#define IFCVF_MAX_QUEUE_PAIRS		1
> +#define IFCVF_MAX_QUEUES		2
> +
> +#define IFCVF_QUEUE_ALIGNMENT		PAGE_SIZE
> +
> +#define IFCVF_MSI_CONFIG_OFF	0
> +#define IFCVF_MSI_QUEUE_OFF	1
> +#define IFCVF_PCI_MAX_RESOURCE	6
> +
> +/* 46 bit CPU physical address, avoid overlap */
> +#define LM_IOVA 0x400000000000
> +
> +#define IFCVF_LM_CFG_SIZE		0x40
> +#define IFCVF_LM_RING_STATE_OFFSET	0x20
> +
> +#define IFCVF_LM_LOGGING_CTRL		0x0
> +
> +#define IFCVF_LM_BASE_ADDR_LOW		0x10
> +#define IFCVF_LM_BASE_ADDR_HIGH		0x14
> +#define IFCVF_LM_END_ADDR_LOW		0x18
> +#define IFCVF_LM_END_ADDR_HIGH		0x1c
> +
> +#define IFCVF_LM_DISABLE		0x0
> +#define IFCVF_LM_ENABLE_VF		0x1
> +#define IFCVF_LM_ENABLE_PF		0x3
> +
> +#define IFCVF_32_BIT_MASK		0xffffffff
> +
> +#define IFC_ERR(dev, fmt, ...)	dev_err(dev, fmt, ##__VA_ARGS__)
> +#define IFC_INFO(dev, fmt, ...)	dev_info(dev, fmt, ##__VA_ARGS__)
> +
> +struct ifcvf_net_config {
> +	u8    mac[6];
> +	u16   status;
> +	u16   max_virtqueue_pairs;
> +} __packed;
> +
> +struct ifcvf_pci_mem_resource {
> +	u64      phys_addr; /**< Physical address, 0 if not resource. */
> +	u64      len;       /**< Length of the resource. */
> +	u8       *addr;     /**< Virtual address, NULL when not mapped. */
> +};
> +
> +struct vring_info {
> +	u64 desc;
> +	u64 avail;
> +	u64 used;
> +	u16 size;
> +	u16 last_avail_idx;
> +	u16 last_used_idx;
> +	bool ready;
> +	char msix_name[256];
> +	struct virtio_mdev_callback cb;
> +};
> +
> +struct ifcvf_hw {
> +	u8	*isr;
> +	u8	notify_bar;
> +	u8	*lm_cfg;
> +	u8	status;
> +	u8	nr_vring;


Is the the number of queue currently used?


> +	u16	*notify_base;
> +	u16	*notify_addr[IFCVF_MAX_QUEUE_PAIRS * 2];
> +	u32	generation;
> +	u32	notify_off_multiplier;
> +	u64	req_features;
> +	struct	virtio_pci_common_cfg *common_cfg;
> +	struct	ifcvf_net_config *dev_cfg;
> +	struct	vring_info vring[IFCVF_MAX_QUEUE_PAIRS * 2];
> +	struct	ifcvf_pci_mem_resource mem_resource[IFCVF_PCI_MAX_RESOURCE];
> +};
> +
> +#define IFC_PRIVATE_TO_VF(adapter) \
> +	(&((struct ifcvf_adapter *)adapter)->vf)
> +
> +#define IFCVF_MAX_INTR (IFCVF_MAX_QUEUE_PAIRS * 2 + 1)


The extra one means the config interrupt?


> +
> +struct ifcvf_adapter {
> +	struct	device *dev;
> +	struct	mutex mdev_lock;


Not used in the patch, move to next one?


> +	int	mdev_count;


Not used.


> +	struct	list_head dma_maps;


This is not used.

Thanks


> +	int	vectors;
> +	struct	ifcvf_hw vf;
> +};
> +
> +int ifcvf_init_hw(struct ifcvf_hw *hw, struct pci_dev *dev);
> +u64 ifcvf_get_features(struct ifcvf_hw *hw);
> +int ifcvf_start_hw(struct ifcvf_hw *hw);
> +void ifcvf_stop_hw(struct ifcvf_hw *hw);
> +void ifcvf_enable_logging(struct ifcvf_hw *hw, u64 log_base, u64 log_size);
> +void ifcvf_enable_logging_vf(struct ifcvf_hw *hw, u64 log_base, u64 log_size);
> +void ifcvf_disable_logging(struct ifcvf_hw *hw);
> +void ifcvf_notify_queue(struct ifcvf_hw *hw, u16 qid);
> +void ifcvf_get_linkstatus(struct ifcvf_hw *hw, u8 *is_linkup);
> +u8 ifcvf_get_notify_region(struct ifcvf_hw *hw);
> +u64 ifcvf_get_queue_notify_off(struct ifcvf_hw *hw, int qid);
> +
> +#endif /* _IFCVF_H_ */

Re: [RFC 1/2] vhost: IFC VF hardware operation layer

[Stephen Hemminger]

On Wed, 16 Oct 2019 09:03:17 +0800
Zhu Lingshan <lingshan.zhu@intel.com> wrote:

> +	IFC_INFO(&dev->dev, "PCI capability mapping:\n"
> +				"common cfg: %p\n"
> +				"notify base: %p\n"
> +				"isr cfg: %p\n"
> +				"device cfg: %p\n"
> +				"multiplier: %u\n",
> +				hw->common_cfg,
> +				hw->notify_base,
> +				hw->isr,
> +				hw->dev_cfg,
> +				hw->notify_off_multiplier);

Since kernel messages go to syslog, syslog does not handle multi-line
messages very well. This should be a single line.

Also, this is the kind of message that should be at the debug
level; something that is useful to the driver developers
but not something that needs to be filling up every end users log.

Re: [RFC 1/2] vhost: IFC VF hardware operation layer

[Stephen Hemminger]

On Wed, 16 Oct 2019 09:03:17 +0800
Zhu Lingshan <lingshan.zhu@intel.com> wrote:

> +int ifcvf_init_hw(struct ifcvf_hw *hw, struct pci_dev *dev)
> +{
> +	int ret;
> +	u8 pos;
> +	struct virtio_pci_cap cap;
> +	u32 i;
> +	u16 notify_off;

For network code, the preferred declaration style is
reverse christmas tree.

[RFC 1/2] vhost: IFC VF hardware operation layer

[Zhu Lingshan]

This commit introduced ifcvf_base layer, which handles IFC VF NIC
hardware operations and configurations.

Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
---
 drivers/vhost/ifcvf/ifcvf_base.c | 390 +++++++++++++++++++++++++++++++++++++++
 drivers/vhost/ifcvf/ifcvf_base.h | 137 ++++++++++++++
 2 files changed, 527 insertions(+)
 create mode 100644 drivers/vhost/ifcvf/ifcvf_base.c
 create mode 100644 drivers/vhost/ifcvf/ifcvf_base.h

diff --git a/drivers/vhost/ifcvf/ifcvf_base.c b/drivers/vhost/ifcvf/ifcvf_base.c
new file mode 100644
index 000000000000..b85e14c9bdcf
--- /dev/null
+++ b/drivers/vhost/ifcvf/ifcvf_base.c
@@ -0,0 +1,390 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2019 Intel Corporation.
+ */
+
+#include "ifcvf_base.h"
+
+static void *get_cap_addr(struct ifcvf_hw *hw, struct virtio_pci_cap *cap)
+{
+	u8 bar = cap->bar;
+	u32 length = cap->length;
+	u32 offset = cap->offset;
+	struct ifcvf_adapter *ifcvf =
+		container_of(hw, struct ifcvf_adapter, vf);
+
+	if (bar >= IFCVF_PCI_MAX_RESOURCE) {
+		IFC_ERR(ifcvf->dev,
+			"Invalid bar number %u to get capabilities.\n", bar);
+		return NULL;
+	}
+
+	if (offset + length < offset) {
+		IFC_ERR(ifcvf->dev, "offset(%u) + length(%u) overflows\n",
+			offset, length);
+		return NULL;
+	}
+
+	if (offset + length > hw->mem_resource[cap->bar].len) {
+		IFC_ERR(ifcvf->dev,
+			"offset(%u) + len(%u) overflows bar%u to get capabilities.\n",
+			offset, length, bar);
+		return NULL;
+	}
+
+	return hw->mem_resource[bar].addr + offset;
+}
+
+int ifcvf_read_config_range(struct pci_dev *dev,
+			uint32_t *val, int size, int where)
+{
+	int i;
+
+	for (i = 0; i < size; i += 4) {
+		if (pci_read_config_dword(dev, where + i, val + i / 4) < 0)
+			return -1;
+	}
+	return 0;
+}
+
+int ifcvf_init_hw(struct ifcvf_hw *hw, struct pci_dev *dev)
+{
+	int ret;
+	u8 pos;
+	struct virtio_pci_cap cap;
+	u32 i;
+	u16 notify_off;
+
+	ret = pci_read_config_byte(dev, PCI_CAPABILITY_LIST, &pos);
+
+	if (ret < 0) {
+		IFC_ERR(&dev->dev, "failed to read PCI capability list.\n");
+		return -EIO;
+	}
+
+	while (pos) {
+		ret = ifcvf_read_config_range(dev, (u32 *)&cap,
+				sizeof(cap), pos);
+
+		if (ret < 0) {
+			IFC_ERR(&dev->dev, "failed to get PCI capability at %x",
+					pos);
+			break;
+		}
+
+		if (cap.cap_vndr != PCI_CAP_ID_VNDR)
+			goto next;
+
+		IFC_INFO(&dev->dev, "read PCI config:\n"
+					"config type: %u.\n"
+					"PCI bar: %u.\n"
+					"PCI bar offset: %u.\n"
+					"PCI config len: %u.\n",
+					cap.cfg_type, cap.bar,
+					cap.offset, cap.length);
+
+		switch (cap.cfg_type) {
+		case VIRTIO_PCI_CAP_COMMON_CFG:
+			hw->common_cfg = get_cap_addr(hw, &cap);
+			IFC_INFO(&dev->dev, "hw->common_cfg = %p.\n",
+					hw->common_cfg);
+			break;
+		case VIRTIO_PCI_CAP_NOTIFY_CFG:
+			pci_read_config_dword(dev, pos + sizeof(cap),
+				&hw->notify_off_multiplier);
+			hw->notify_bar = cap.bar;
+			hw->notify_base = get_cap_addr(hw, &cap);
+			IFC_INFO(&dev->dev, "hw->notify_base = %p.\n",
+					hw->notify_base);
+			break;
+		case VIRTIO_PCI_CAP_ISR_CFG:
+			hw->isr = get_cap_addr(hw, &cap);
+			IFC_INFO(&dev->dev, "hw->isr = %p.\n", hw->isr);
+			break;
+		case VIRTIO_PCI_CAP_DEVICE_CFG:
+			hw->dev_cfg = get_cap_addr(hw, &cap);
+			IFC_INFO(&dev->dev, "hw->dev_cfg = %p.\n", hw->dev_cfg);
+			break;
+		}
+next:
+		pos = cap.cap_next;
+	}
+
+	if (hw->common_cfg == NULL || hw->notify_base == NULL ||
+		hw->isr == NULL || hw->dev_cfg == NULL) {
+		IFC_ERR(&dev->dev, "Incomplete PCI capabilities.\n");
+		return -1;
+	}
+
+	for (i = 0; i < (IFCVF_MAX_QUEUE_PAIRS * 2); i++) {
+		iowrite16(i, &hw->common_cfg->queue_select);
+		notify_off = ioread16(&hw->common_cfg->queue_notify_off);
+		hw->notify_addr[i] = (void *)((u8 *)hw->notify_base +
+				notify_off * hw->notify_off_multiplier);
+	}
+
+	hw->lm_cfg = hw->mem_resource[4].addr;
+
+	IFC_INFO(&dev->dev, "PCI capability mapping:\n"
+				"common cfg: %p\n"
+				"notify base: %p\n"
+				"isr cfg: %p\n"
+				"device cfg: %p\n"
+				"multiplier: %u\n",
+				hw->common_cfg,
+				hw->notify_base,
+				hw->isr,
+				hw->dev_cfg,
+				hw->notify_off_multiplier);
+
+	return 0;
+}
+
+static u8 ifcvf_get_status(struct ifcvf_hw *hw)
+{
+	return ioread8(&hw->common_cfg->device_status);
+}
+
+static void ifcvf_set_status(struct ifcvf_hw *hw, u8 status)
+{
+	iowrite8(status, &hw->common_cfg->device_status);
+}
+
+static void ifcvf_reset(struct ifcvf_hw *hw)
+{
+	ifcvf_set_status(hw, 0);
+
+	/* flush status write */
+	ifcvf_get_status(hw);
+	hw->generation++;
+}
+
+static void ifcvf_add_status(struct ifcvf_hw *hw, u8 status)
+{
+	if (status != 0)
+		status |= ifcvf_get_status(hw);
+
+	ifcvf_set_status(hw, status);
+	ifcvf_get_status(hw);
+}
+
+u64 ifcvf_get_features(struct ifcvf_hw *hw)
+{
+	u32 features_lo, features_hi;
+	struct virtio_pci_common_cfg *cfg = hw->common_cfg;
+
+	iowrite32(0, &cfg->device_feature_select);
+	features_lo = ioread32(&cfg->device_feature);
+
+	iowrite32(1, &cfg->device_feature_select);
+	features_hi = ioread32(&cfg->device_feature);
+
+	return ((u64)features_hi << 32) | features_lo;
+}
+static int ifcvf_with_feature(struct ifcvf_hw *hw, u64 bit)
+{
+	return (hw->req_features & (1ULL << bit)) != 0;
+}
+
+static void ifcvf_read_dev_config(struct ifcvf_hw *hw, u64 offset,
+		       void *dst, int length)
+{
+	int i;
+	u8 *p;
+	u8 old_gen, new_gen;
+
+	do {
+		old_gen = ioread8(&hw->common_cfg->config_generation);
+
+		p = dst;
+		for (i = 0; i < length; i++)
+			*p++ = ioread8((u8 *)hw->dev_cfg + offset + i);
+
+		new_gen = ioread8(&hw->common_cfg->config_generation);
+	} while (old_gen != new_gen);
+}
+
+void ifcvf_get_linkstatus(struct ifcvf_hw *hw, u8 *is_linkup)
+{
+	u16 status;
+	u64 host_features;
+
+	host_features = ifcvf_get_features(hw);
+	if (ifcvf_with_feature(hw, VIRTIO_NET_F_STATUS)) {
+		ifcvf_read_dev_config(hw,
+				offsetof(struct ifcvf_net_config, status),
+				&status, sizeof(status));
+		if ((status & VIRTIO_NET_S_LINK_UP) == 0)
+			(*is_linkup) = 1;
+		else
+			(*is_linkup) = 0;
+	} else
+		(*is_linkup) = 0;
+}
+
+static void ifcvf_set_features(struct ifcvf_hw *hw, u64 features)
+{
+	struct virtio_pci_common_cfg *cfg = hw->common_cfg;
+
+	iowrite32(0, &cfg->guest_feature_select);
+	iowrite32(features & ((1ULL << 32) - 1), &cfg->guest_feature);
+
+	iowrite32(1, &cfg->guest_feature_select);
+	iowrite32(features >> 32, &cfg->guest_feature);
+}
+
+static int ifcvf_config_features(struct ifcvf_hw *hw)
+{
+	u64 host_features;
+	struct ifcvf_adapter *ifcvf =
+		container_of(hw, struct ifcvf_adapter, vf);
+
+	host_features = ifcvf_get_features(hw);
+	hw->req_features &= host_features;
+
+	ifcvf_set_features(hw, hw->req_features);
+	ifcvf_add_status(hw, VIRTIO_CONFIG_S_FEATURES_OK);
+
+	if (!(ifcvf_get_status(hw) & VIRTIO_CONFIG_S_FEATURES_OK)) {
+		IFC_ERR(ifcvf->dev, "Failed to set FEATURES_OK status\n");
+		return -EIO;
+	}
+
+	return 0;
+}
+
+static void io_write64_twopart(u64 val, u32 *lo, u32 *hi)
+{
+	iowrite32(val & ((1ULL << 32) - 1), lo);
+	iowrite32(val >> 32, hi);
+}
+
+static int ifcvf_hw_enable(struct ifcvf_hw *hw)
+{
+	struct virtio_pci_common_cfg *cfg;
+	u8 *lm_cfg;
+	u32 i;
+	struct ifcvf_adapter *ifcvf =
+		container_of(hw, struct ifcvf_adapter, vf);
+
+	cfg = hw->common_cfg;
+	lm_cfg = hw->lm_cfg;
+
+	iowrite16(IFCVF_MSI_CONFIG_OFF, &cfg->msix_config);
+	if (ioread16(&cfg->msix_config) == VIRTIO_MSI_NO_VECTOR) {
+		IFC_ERR(ifcvf->dev, "No msix vector for device config.\n");
+		return -1;
+	}
+
+	for (i = 0; i < hw->nr_vring; i++) {
+		iowrite16(i, &cfg->queue_select);
+		io_write64_twopart(hw->vring[i].desc, &cfg->queue_desc_lo,
+				&cfg->queue_desc_hi);
+		io_write64_twopart(hw->vring[i].avail, &cfg->queue_avail_lo,
+				&cfg->queue_avail_hi);
+		io_write64_twopart(hw->vring[i].used, &cfg->queue_used_lo,
+				&cfg->queue_used_hi);
+		iowrite16(hw->vring[i].size, &cfg->queue_size);
+
+		*(u32 *)(lm_cfg + IFCVF_LM_RING_STATE_OFFSET +
+				(i / 2) * IFCVF_LM_CFG_SIZE + (i % 2) * 4) =
+			(u32)hw->vring[i].last_avail_idx |
+			((u32)hw->vring[i].last_used_idx << 16);
+
+		iowrite16(i + IFCVF_MSI_QUEUE_OFF, &cfg->queue_msix_vector);
+		if (ioread16(&cfg->queue_msix_vector) ==
+				VIRTIO_MSI_NO_VECTOR) {
+			IFC_ERR(ifcvf->dev,
+				"No msix vector for queue %u.\n", i);
+			return -1;
+		}
+
+		iowrite16(1, &cfg->queue_enable);
+	}
+
+	return 0;
+}
+
+static void ifcvf_hw_disable(struct ifcvf_hw *hw)
+{
+	u32 i;
+	struct virtio_pci_common_cfg *cfg;
+
+	cfg = hw->common_cfg;
+
+	iowrite16(VIRTIO_MSI_NO_VECTOR, &cfg->msix_config);
+	for (i = 0; i < hw->nr_vring; i++) {
+		iowrite16(i, &cfg->queue_select);
+		iowrite16(0, &cfg->queue_enable);
+		iowrite16(VIRTIO_MSI_NO_VECTOR, &cfg->queue_msix_vector);
+	}
+}
+
+int ifcvf_start_hw(struct ifcvf_hw *hw)
+{
+	ifcvf_reset(hw);
+	ifcvf_add_status(hw, VIRTIO_CONFIG_S_ACKNOWLEDGE);
+	ifcvf_add_status(hw, VIRTIO_CONFIG_S_DRIVER);
+
+	if (ifcvf_config_features(hw) < 0)
+		return -1;
+
+	if (ifcvf_hw_enable(hw) < 0)
+		return -1;
+
+	ifcvf_add_status(hw, VIRTIO_CONFIG_S_DRIVER_OK);
+
+	return 0;
+}
+
+void ifcvf_stop_hw(struct ifcvf_hw *hw)
+{
+	ifcvf_hw_disable(hw);
+	ifcvf_reset(hw);
+}
+
+void ifcvf_enable_logging_vf(struct ifcvf_hw *hw, u64 log_base, u64 log_size)
+{
+	u8 *lm_cfg;
+
+	lm_cfg = hw->lm_cfg;
+
+	*(u32 *)(lm_cfg + IFCVF_LM_BASE_ADDR_LOW) =
+		log_base & IFCVF_32_BIT_MASK;
+
+	*(u32 *)(lm_cfg + IFCVF_LM_BASE_ADDR_HIGH) =
+		(log_base >> 32) & IFCVF_32_BIT_MASK;
+
+	*(u32 *)(lm_cfg + IFCVF_LM_END_ADDR_LOW) =
+		(log_base + log_size) & IFCVF_32_BIT_MASK;
+
+	*(u32 *)(lm_cfg + IFCVF_LM_END_ADDR_HIGH) =
+		((log_base + log_size) >> 32) & IFCVF_32_BIT_MASK;
+
+	*(u32 *)(lm_cfg + IFCVF_LM_LOGGING_CTRL) = IFCVF_LM_ENABLE_VF;
+}
+
+void ifcvf_disable_logging(struct ifcvf_hw *hw)
+{
+	u8 *lm_cfg;
+
+	lm_cfg = hw->lm_cfg;
+	*(u32 *)(lm_cfg + IFCVF_LM_LOGGING_CTRL) = IFCVF_LM_DISABLE;
+}
+
+void ifcvf_notify_queue(struct ifcvf_hw *hw, u16 qid)
+{
+
+	iowrite16(qid, hw->notify_addr[qid]);
+}
+
+u8 ifcvf_get_notify_region(struct ifcvf_hw *hw)
+{
+	return hw->notify_bar;
+}
+
+u64 ifcvf_get_queue_notify_off(struct ifcvf_hw *hw, int qid)
+{
+	return (u8 *)hw->notify_addr[qid] -
+		(u8 *)hw->mem_resource[hw->notify_bar].addr;
+}
diff --git a/drivers/vhost/ifcvf/ifcvf_base.h b/drivers/vhost/ifcvf/ifcvf_base.h
new file mode 100644
index 000000000000..1ab1a1c40f24
--- /dev/null
+++ b/drivers/vhost/ifcvf/ifcvf_base.h
@@ -0,0 +1,137 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/*
+ * Copyright (C) 2019 Intel Corporation.
+ */
+
+#ifndef _IFCVF_H_
+#define _IFCVF_H_
+
+#include <linux/virtio_mdev.h>
+#include <linux/pci.h>
+#include <linux/pci_regs.h>
+#include <uapi/linux/virtio_net.h>
+#include <uapi/linux/virtio_config.h>
+#include <uapi/linux/virtio_pci.h>
+
+#define IFCVF_VENDOR_ID         0x1AF4
+#define IFCVF_DEVICE_ID         0x1041
+#define IFCVF_SUBSYS_VENDOR_ID  0x8086
+#define IFCVF_SUBSYS_DEVICE_ID  0x001A
+
+/*
+ * Some ifcvf feature bits (currently bits 28 through 31) are
+ * reserved for the transport being used (eg. ifcvf_ring), the
+ * rest are per-device feature bits.
+ */
+#define IFCVF_TRANSPORT_F_START 28
+#define IFCVF_TRANSPORT_F_END   34
+
+#define IFC_SUPPORTED_FEATURES \
+		((1ULL << VIRTIO_NET_F_MAC)			| \
+		 (1ULL << VIRTIO_F_ANY_LAYOUT)			| \
+		 (1ULL << VIRTIO_F_VERSION_1)			| \
+		 (1ULL << VHOST_F_LOG_ALL)			| \
+		 (1ULL << VIRTIO_NET_F_GUEST_ANNOUNCE)		| \
+		 (1ULL << VIRTIO_NET_F_CTRL_VQ)			| \
+		 (1ULL << VIRTIO_NET_F_STATUS)			| \
+		 (1ULL << VIRTIO_NET_F_MRG_RXBUF)) /* not fully supported */
+
+#define IFCVF_MAX_QUEUE_PAIRS		1
+#define IFCVF_MAX_QUEUES		2
+
+#define IFCVF_QUEUE_ALIGNMENT		PAGE_SIZE
+
+#define IFCVF_MSI_CONFIG_OFF	0
+#define IFCVF_MSI_QUEUE_OFF	1
+#define IFCVF_PCI_MAX_RESOURCE	6
+
+/* 46 bit CPU physical address, avoid overlap */
+#define LM_IOVA 0x400000000000
+
+#define IFCVF_LM_CFG_SIZE		0x40
+#define IFCVF_LM_RING_STATE_OFFSET	0x20
+
+#define IFCVF_LM_LOGGING_CTRL		0x0
+
+#define IFCVF_LM_BASE_ADDR_LOW		0x10
+#define IFCVF_LM_BASE_ADDR_HIGH		0x14
+#define IFCVF_LM_END_ADDR_LOW		0x18
+#define IFCVF_LM_END_ADDR_HIGH		0x1c
+
+#define IFCVF_LM_DISABLE		0x0
+#define IFCVF_LM_ENABLE_VF		0x1
+#define IFCVF_LM_ENABLE_PF		0x3
+
+#define IFCVF_32_BIT_MASK		0xffffffff
+
+#define IFC_ERR(dev, fmt, ...)	dev_err(dev, fmt, ##__VA_ARGS__)
+#define IFC_INFO(dev, fmt, ...)	dev_info(dev, fmt, ##__VA_ARGS__)
+
+struct ifcvf_net_config {
+	u8    mac[6];
+	u16   status;
+	u16   max_virtqueue_pairs;
+} __packed;
+
+struct ifcvf_pci_mem_resource {
+	u64      phys_addr; /**< Physical address, 0 if not resource. */
+	u64      len;       /**< Length of the resource. */
+	u8       *addr;     /**< Virtual address, NULL when not mapped. */
+};
+
+struct vring_info {
+	u64 desc;
+	u64 avail;
+	u64 used;
+	u16 size;
+	u16 last_avail_idx;
+	u16 last_used_idx;
+	bool ready;
+	char msix_name[256];
+	struct virtio_mdev_callback cb;
+};
+
+struct ifcvf_hw {
+	u8	*isr;
+	u8	notify_bar;
+	u8	*lm_cfg;
+	u8	status;
+	u8	nr_vring;
+	u16	*notify_base;
+	u16	*notify_addr[IFCVF_MAX_QUEUE_PAIRS * 2];
+	u32	generation;
+	u32	notify_off_multiplier;
+	u64	req_features;
+	struct	virtio_pci_common_cfg *common_cfg;
+	struct	ifcvf_net_config *dev_cfg;
+	struct	vring_info vring[IFCVF_MAX_QUEUE_PAIRS * 2];
+	struct	ifcvf_pci_mem_resource mem_resource[IFCVF_PCI_MAX_RESOURCE];
+};
+
+#define IFC_PRIVATE_TO_VF(adapter) \
+	(&((struct ifcvf_adapter *)adapter)->vf)
+
+#define IFCVF_MAX_INTR (IFCVF_MAX_QUEUE_PAIRS * 2 + 1)
+
+struct ifcvf_adapter {
+	struct	device *dev;
+	struct	mutex mdev_lock;
+	int	mdev_count;
+	struct	list_head dma_maps;
+	int	vectors;
+	struct	ifcvf_hw vf;
+};
+
+int ifcvf_init_hw(struct ifcvf_hw *hw, struct pci_dev *dev);
+u64 ifcvf_get_features(struct ifcvf_hw *hw);
+int ifcvf_start_hw(struct ifcvf_hw *hw);
+void ifcvf_stop_hw(struct ifcvf_hw *hw);
+void ifcvf_enable_logging(struct ifcvf_hw *hw, u64 log_base, u64 log_size);
+void ifcvf_enable_logging_vf(struct ifcvf_hw *hw, u64 log_base, u64 log_size);
+void ifcvf_disable_logging(struct ifcvf_hw *hw);
+void ifcvf_notify_queue(struct ifcvf_hw *hw, u16 qid);
+void ifcvf_get_linkstatus(struct ifcvf_hw *hw, u8 *is_linkup);
+u8 ifcvf_get_notify_region(struct ifcvf_hw *hw);
+u64 ifcvf_get_queue_notify_off(struct ifcvf_hw *hw, int qid);
+
+#endif /* _IFCVF_H_ */
-- 
2.16.4

[RFC 1/2] vhost: IFC VF hardware operation layer

[Zhu Lingshan]

This commit introduced ifcvf_base layer, which handles IFC VF NIC
hardware operations and configurations.

Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
---
 drivers/vhost/ifcvf/ifcvf_base.c | 390 +++++++++++++++++++++++++++++++++++++++
 drivers/vhost/ifcvf/ifcvf_base.h | 137 ++++++++++++++
 2 files changed, 527 insertions(+)
 create mode 100644 drivers/vhost/ifcvf/ifcvf_base.c
 create mode 100644 drivers/vhost/ifcvf/ifcvf_base.h

diff --git a/drivers/vhost/ifcvf/ifcvf_base.c b/drivers/vhost/ifcvf/ifcvf_base.c
new file mode 100644
index 000000000000..b85e14c9bdcf
--- /dev/null
+++ b/drivers/vhost/ifcvf/ifcvf_base.c
@@ -0,0 +1,390 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2019 Intel Corporation.
+ */
+
+#include "ifcvf_base.h"
+
+static void *get_cap_addr(struct ifcvf_hw *hw, struct virtio_pci_cap *cap)
+{
+	u8 bar = cap->bar;
+	u32 length = cap->length;
+	u32 offset = cap->offset;
+	struct ifcvf_adapter *ifcvf =
+		container_of(hw, struct ifcvf_adapter, vf);
+
+	if (bar >= IFCVF_PCI_MAX_RESOURCE) {
+		IFC_ERR(ifcvf->dev,
+			"Invalid bar number %u to get capabilities.\n", bar);
+		return NULL;
+	}
+
+	if (offset + length < offset) {
+		IFC_ERR(ifcvf->dev, "offset(%u) + length(%u) overflows\n",
+			offset, length);
+		return NULL;
+	}
+
+	if (offset + length > hw->mem_resource[cap->bar].len) {
+		IFC_ERR(ifcvf->dev,
+			"offset(%u) + len(%u) overflows bar%u to get capabilities.\n",
+			offset, length, bar);
+		return NULL;
+	}
+
+	return hw->mem_resource[bar].addr + offset;
+}
+
+int ifcvf_read_config_range(struct pci_dev *dev,
+			uint32_t *val, int size, int where)
+{
+	int i;
+
+	for (i = 0; i < size; i += 4) {
+		if (pci_read_config_dword(dev, where + i, val + i / 4) < 0)
+			return -1;
+	}
+	return 0;
+}
+
+int ifcvf_init_hw(struct ifcvf_hw *hw, struct pci_dev *dev)
+{
+	int ret;
+	u8 pos;
+	struct virtio_pci_cap cap;
+	u32 i;
+	u16 notify_off;
+
+	ret = pci_read_config_byte(dev, PCI_CAPABILITY_LIST, &pos);
+
+	if (ret < 0) {
+		IFC_ERR(&dev->dev, "failed to read PCI capability list.\n");
+		return -EIO;
+	}
+
+	while (pos) {
+		ret = ifcvf_read_config_range(dev, (u32 *)&cap,
+				sizeof(cap), pos);
+
+		if (ret < 0) {
+			IFC_ERR(&dev->dev, "failed to get PCI capability at %x",
+					pos);
+			break;
+		}
+
+		if (cap.cap_vndr != PCI_CAP_ID_VNDR)
+			goto next;
+
+		IFC_INFO(&dev->dev, "read PCI config:\n"
+					"config type: %u.\n"
+					"PCI bar: %u.\n"
+					"PCI bar offset: %u.\n"
+					"PCI config len: %u.\n",
+					cap.cfg_type, cap.bar,
+					cap.offset, cap.length);
+
+		switch (cap.cfg_type) {
+		case VIRTIO_PCI_CAP_COMMON_CFG:
+			hw->common_cfg = get_cap_addr(hw, &cap);
+			IFC_INFO(&dev->dev, "hw->common_cfg = %p.\n",
+					hw->common_cfg);
+			break;
+		case VIRTIO_PCI_CAP_NOTIFY_CFG:
+			pci_read_config_dword(dev, pos + sizeof(cap),
+				&hw->notify_off_multiplier);
+			hw->notify_bar = cap.bar;
+			hw->notify_base = get_cap_addr(hw, &cap);
+			IFC_INFO(&dev->dev, "hw->notify_base = %p.\n",
+					hw->notify_base);
+			break;
+		case VIRTIO_PCI_CAP_ISR_CFG:
+			hw->isr = get_cap_addr(hw, &cap);
+			IFC_INFO(&dev->dev, "hw->isr = %p.\n", hw->isr);
+			break;
+		case VIRTIO_PCI_CAP_DEVICE_CFG:
+			hw->dev_cfg = get_cap_addr(hw, &cap);
+			IFC_INFO(&dev->dev, "hw->dev_cfg = %p.\n", hw->dev_cfg);
+			break;
+		}
+next:
+		pos = cap.cap_next;
+	}
+
+	if (hw->common_cfg == NULL || hw->notify_base == NULL ||
+		hw->isr == NULL || hw->dev_cfg == NULL) {
+		IFC_ERR(&dev->dev, "Incomplete PCI capabilities.\n");
+		return -1;
+	}
+
+	for (i = 0; i < (IFCVF_MAX_QUEUE_PAIRS * 2); i++) {
+		iowrite16(i, &hw->common_cfg->queue_select);
+		notify_off = ioread16(&hw->common_cfg->queue_notify_off);
+		hw->notify_addr[i] = (void *)((u8 *)hw->notify_base +
+				notify_off * hw->notify_off_multiplier);
+	}
+
+	hw->lm_cfg = hw->mem_resource[4].addr;
+
+	IFC_INFO(&dev->dev, "PCI capability mapping:\n"
+				"common cfg: %p\n"
+				"notify base: %p\n"
+				"isr cfg: %p\n"
+				"device cfg: %p\n"
+				"multiplier: %u\n",
+				hw->common_cfg,
+				hw->notify_base,
+				hw->isr,
+				hw->dev_cfg,
+				hw->notify_off_multiplier);
+
+	return 0;
+}
+
+static u8 ifcvf_get_status(struct ifcvf_hw *hw)
+{
+	return ioread8(&hw->common_cfg->device_status);
+}
+
+static void ifcvf_set_status(struct ifcvf_hw *hw, u8 status)
+{
+	iowrite8(status, &hw->common_cfg->device_status);
+}
+
+static void ifcvf_reset(struct ifcvf_hw *hw)
+{
+	ifcvf_set_status(hw, 0);
+
+	/* flush status write */
+	ifcvf_get_status(hw);
+	hw->generation++;
+}
+
+static void ifcvf_add_status(struct ifcvf_hw *hw, u8 status)
+{
+	if (status != 0)
+		status |= ifcvf_get_status(hw);
+
+	ifcvf_set_status(hw, status);
+	ifcvf_get_status(hw);
+}
+
+u64 ifcvf_get_features(struct ifcvf_hw *hw)
+{
+	u32 features_lo, features_hi;
+	struct virtio_pci_common_cfg *cfg = hw->common_cfg;
+
+	iowrite32(0, &cfg->device_feature_select);
+	features_lo = ioread32(&cfg->device_feature);
+
+	iowrite32(1, &cfg->device_feature_select);
+	features_hi = ioread32(&cfg->device_feature);
+
+	return ((u64)features_hi << 32) | features_lo;
+}
+static int ifcvf_with_feature(struct ifcvf_hw *hw, u64 bit)
+{
+	return (hw->req_features & (1ULL << bit)) != 0;
+}
+
+static void ifcvf_read_dev_config(struct ifcvf_hw *hw, u64 offset,
+		       void *dst, int length)
+{
+	int i;
+	u8 *p;
+	u8 old_gen, new_gen;
+
+	do {
+		old_gen = ioread8(&hw->common_cfg->config_generation);
+
+		p = dst;
+		for (i = 0; i < length; i++)
+			*p++ = ioread8((u8 *)hw->dev_cfg + offset + i);
+
+		new_gen = ioread8(&hw->common_cfg->config_generation);
+	} while (old_gen != new_gen);
+}
+
+void ifcvf_get_linkstatus(struct ifcvf_hw *hw, u8 *is_linkup)
+{
+	u16 status;
+	u64 host_features;
+
+	host_features = ifcvf_get_features(hw);
+	if (ifcvf_with_feature(hw, VIRTIO_NET_F_STATUS)) {
+		ifcvf_read_dev_config(hw,
+				offsetof(struct ifcvf_net_config, status),
+				&status, sizeof(status));
+		if ((status & VIRTIO_NET_S_LINK_UP) == 0)
+			(*is_linkup) = 1;
+		else
+			(*is_linkup) = 0;
+	} else
+		(*is_linkup) = 0;
+}
+
+static void ifcvf_set_features(struct ifcvf_hw *hw, u64 features)
+{
+	struct virtio_pci_common_cfg *cfg = hw->common_cfg;
+
+	iowrite32(0, &cfg->guest_feature_select);
+	iowrite32(features & ((1ULL << 32) - 1), &cfg->guest_feature);
+
+	iowrite32(1, &cfg->guest_feature_select);
+	iowrite32(features >> 32, &cfg->guest_feature);
+}
+
+static int ifcvf_config_features(struct ifcvf_hw *hw)
+{
+	u64 host_features;
+	struct ifcvf_adapter *ifcvf =
+		container_of(hw, struct ifcvf_adapter, vf);
+
+	host_features = ifcvf_get_features(hw);
+	hw->req_features &= host_features;
+
+	ifcvf_set_features(hw, hw->req_features);
+	ifcvf_add_status(hw, VIRTIO_CONFIG_S_FEATURES_OK);
+
+	if (!(ifcvf_get_status(hw) & VIRTIO_CONFIG_S_FEATURES_OK)) {
+		IFC_ERR(ifcvf->dev, "Failed to set FEATURES_OK status\n");
+		return -EIO;
+	}
+
+	return 0;
+}
+
+static void io_write64_twopart(u64 val, u32 *lo, u32 *hi)
+{
+	iowrite32(val & ((1ULL << 32) - 1), lo);
+	iowrite32(val >> 32, hi);
+}
+
+static int ifcvf_hw_enable(struct ifcvf_hw *hw)
+{
+	struct virtio_pci_common_cfg *cfg;
+	u8 *lm_cfg;
+	u32 i;
+	struct ifcvf_adapter *ifcvf =
+		container_of(hw, struct ifcvf_adapter, vf);
+
+	cfg = hw->common_cfg;
+	lm_cfg = hw->lm_cfg;
+
+	iowrite16(IFCVF_MSI_CONFIG_OFF, &cfg->msix_config);
+	if (ioread16(&cfg->msix_config) == VIRTIO_MSI_NO_VECTOR) {
+		IFC_ERR(ifcvf->dev, "No msix vector for device config.\n");
+		return -1;
+	}
+
+	for (i = 0; i < hw->nr_vring; i++) {
+		iowrite16(i, &cfg->queue_select);
+		io_write64_twopart(hw->vring[i].desc, &cfg->queue_desc_lo,
+				&cfg->queue_desc_hi);
+		io_write64_twopart(hw->vring[i].avail, &cfg->queue_avail_lo,
+				&cfg->queue_avail_hi);
+		io_write64_twopart(hw->vring[i].used, &cfg->queue_used_lo,
+				&cfg->queue_used_hi);
+		iowrite16(hw->vring[i].size, &cfg->queue_size);
+
+		*(u32 *)(lm_cfg + IFCVF_LM_RING_STATE_OFFSET +
+				(i / 2) * IFCVF_LM_CFG_SIZE + (i % 2) * 4) =
+			(u32)hw->vring[i].last_avail_idx |
+			((u32)hw->vring[i].last_used_idx << 16);
+
+		iowrite16(i + IFCVF_MSI_QUEUE_OFF, &cfg->queue_msix_vector);
+		if (ioread16(&cfg->queue_msix_vector) ==
+				VIRTIO_MSI_NO_VECTOR) {
+			IFC_ERR(ifcvf->dev,
+				"No msix vector for queue %u.\n", i);
+			return -1;
+		}
+
+		iowrite16(1, &cfg->queue_enable);
+	}
+
+	return 0;
+}
+
+static void ifcvf_hw_disable(struct ifcvf_hw *hw)
+{
+	u32 i;
+	struct virtio_pci_common_cfg *cfg;
+
+	cfg = hw->common_cfg;
+
+	iowrite16(VIRTIO_MSI_NO_VECTOR, &cfg->msix_config);
+	for (i = 0; i < hw->nr_vring; i++) {
+		iowrite16(i, &cfg->queue_select);
+		iowrite16(0, &cfg->queue_enable);
+		iowrite16(VIRTIO_MSI_NO_VECTOR, &cfg->queue_msix_vector);
+	}
+}
+
+int ifcvf_start_hw(struct ifcvf_hw *hw)
+{
+	ifcvf_reset(hw);
+	ifcvf_add_status(hw, VIRTIO_CONFIG_S_ACKNOWLEDGE);
+	ifcvf_add_status(hw, VIRTIO_CONFIG_S_DRIVER);
+
+	if (ifcvf_config_features(hw) < 0)
+		return -1;
+
+	if (ifcvf_hw_enable(hw) < 0)
+		return -1;
+
+	ifcvf_add_status(hw, VIRTIO_CONFIG_S_DRIVER_OK);
+
+	return 0;
+}
+
+void ifcvf_stop_hw(struct ifcvf_hw *hw)
+{
+	ifcvf_hw_disable(hw);
+	ifcvf_reset(hw);
+}
+
+void ifcvf_enable_logging_vf(struct ifcvf_hw *hw, u64 log_base, u64 log_size)
+{
+	u8 *lm_cfg;
+
+	lm_cfg = hw->lm_cfg;
+
+	*(u32 *)(lm_cfg + IFCVF_LM_BASE_ADDR_LOW) =
+		log_base & IFCVF_32_BIT_MASK;
+
+	*(u32 *)(lm_cfg + IFCVF_LM_BASE_ADDR_HIGH) =
+		(log_base >> 32) & IFCVF_32_BIT_MASK;
+
+	*(u32 *)(lm_cfg + IFCVF_LM_END_ADDR_LOW) =
+		(log_base + log_size) & IFCVF_32_BIT_MASK;
+
+	*(u32 *)(lm_cfg + IFCVF_LM_END_ADDR_HIGH) =
+		((log_base + log_size) >> 32) & IFCVF_32_BIT_MASK;
+
+	*(u32 *)(lm_cfg + IFCVF_LM_LOGGING_CTRL) = IFCVF_LM_ENABLE_VF;
+}
+
+void ifcvf_disable_logging(struct ifcvf_hw *hw)
+{
+	u8 *lm_cfg;
+
+	lm_cfg = hw->lm_cfg;
+	*(u32 *)(lm_cfg + IFCVF_LM_LOGGING_CTRL) = IFCVF_LM_DISABLE;
+}
+
+void ifcvf_notify_queue(struct ifcvf_hw *hw, u16 qid)
+{
+
+	iowrite16(qid, hw->notify_addr[qid]);
+}
+
+u8 ifcvf_get_notify_region(struct ifcvf_hw *hw)
+{
+	return hw->notify_bar;
+}
+
+u64 ifcvf_get_queue_notify_off(struct ifcvf_hw *hw, int qid)
+{
+	return (u8 *)hw->notify_addr[qid] -
+		(u8 *)hw->mem_resource[hw->notify_bar].addr;
+}
diff --git a/drivers/vhost/ifcvf/ifcvf_base.h b/drivers/vhost/ifcvf/ifcvf_base.h
new file mode 100644
index 000000000000..1ab1a1c40f24
--- /dev/null
+++ b/drivers/vhost/ifcvf/ifcvf_base.h
@@ -0,0 +1,137 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+/*
+ * Copyright (C) 2019 Intel Corporation.
+ */
+
+#ifndef _IFCVF_H_
+#define _IFCVF_H_
+
+#include <linux/virtio_mdev.h>
+#include <linux/pci.h>
+#include <linux/pci_regs.h>
+#include <uapi/linux/virtio_net.h>
+#include <uapi/linux/virtio_config.h>
+#include <uapi/linux/virtio_pci.h>
+
+#define IFCVF_VENDOR_ID         0x1AF4
+#define IFCVF_DEVICE_ID         0x1041
+#define IFCVF_SUBSYS_VENDOR_ID  0x8086
+#define IFCVF_SUBSYS_DEVICE_ID  0x001A
+
+/*
+ * Some ifcvf feature bits (currently bits 28 through 31) are
+ * reserved for the transport being used (eg. ifcvf_ring), the
+ * rest are per-device feature bits.
+ */
+#define IFCVF_TRANSPORT_F_START 28
+#define IFCVF_TRANSPORT_F_END   34
+
+#define IFC_SUPPORTED_FEATURES \
+		((1ULL << VIRTIO_NET_F_MAC)			| \
+		 (1ULL << VIRTIO_F_ANY_LAYOUT)			| \
+		 (1ULL << VIRTIO_F_VERSION_1)			| \
+		 (1ULL << VHOST_F_LOG_ALL)			| \
+		 (1ULL << VIRTIO_NET_F_GUEST_ANNOUNCE)		| \
+		 (1ULL << VIRTIO_NET_F_CTRL_VQ)			| \
+		 (1ULL << VIRTIO_NET_F_STATUS)			| \
+		 (1ULL << VIRTIO_NET_F_MRG_RXBUF)) /* not fully supported */
+
+#define IFCVF_MAX_QUEUE_PAIRS		1
+#define IFCVF_MAX_QUEUES		2
+
+#define IFCVF_QUEUE_ALIGNMENT		PAGE_SIZE
+
+#define IFCVF_MSI_CONFIG_OFF	0
+#define IFCVF_MSI_QUEUE_OFF	1
+#define IFCVF_PCI_MAX_RESOURCE	6
+
+/* 46 bit CPU physical address, avoid overlap */
+#define LM_IOVA 0x400000000000
+
+#define IFCVF_LM_CFG_SIZE		0x40
+#define IFCVF_LM_RING_STATE_OFFSET	0x20
+
+#define IFCVF_LM_LOGGING_CTRL		0x0
+
+#define IFCVF_LM_BASE_ADDR_LOW		0x10
+#define IFCVF_LM_BASE_ADDR_HIGH		0x14
+#define IFCVF_LM_END_ADDR_LOW		0x18
+#define IFCVF_LM_END_ADDR_HIGH		0x1c
+
+#define IFCVF_LM_DISABLE		0x0
+#define IFCVF_LM_ENABLE_VF		0x1
+#define IFCVF_LM_ENABLE_PF		0x3
+
+#define IFCVF_32_BIT_MASK		0xffffffff
+
+#define IFC_ERR(dev, fmt, ...)	dev_err(dev, fmt, ##__VA_ARGS__)
+#define IFC_INFO(dev, fmt, ...)	dev_info(dev, fmt, ##__VA_ARGS__)
+
+struct ifcvf_net_config {
+	u8    mac[6];
+	u16   status;
+	u16   max_virtqueue_pairs;
+} __packed;
+
+struct ifcvf_pci_mem_resource {
+	u64      phys_addr; /**< Physical address, 0 if not resource. */
+	u64      len;       /**< Length of the resource. */
+	u8       *addr;     /**< Virtual address, NULL when not mapped. */
+};
+
+struct vring_info {
+	u64 desc;
+	u64 avail;
+	u64 used;
+	u16 size;
+	u16 last_avail_idx;
+	u16 last_used_idx;
+	bool ready;
+	char msix_name[256];
+	struct virtio_mdev_callback cb;
+};
+
+struct ifcvf_hw {
+	u8	*isr;
+	u8	notify_bar;
+	u8	*lm_cfg;
+	u8	status;
+	u8	nr_vring;
+	u16	*notify_base;
+	u16	*notify_addr[IFCVF_MAX_QUEUE_PAIRS * 2];
+	u32	generation;
+	u32	notify_off_multiplier;
+	u64	req_features;
+	struct	virtio_pci_common_cfg *common_cfg;
+	struct	ifcvf_net_config *dev_cfg;
+	struct	vring_info vring[IFCVF_MAX_QUEUE_PAIRS * 2];
+	struct	ifcvf_pci_mem_resource mem_resource[IFCVF_PCI_MAX_RESOURCE];
+};
+
+#define IFC_PRIVATE_TO_VF(adapter) \
+	(&((struct ifcvf_adapter *)adapter)->vf)
+
+#define IFCVF_MAX_INTR (IFCVF_MAX_QUEUE_PAIRS * 2 + 1)
+
+struct ifcvf_adapter {
+	struct	device *dev;
+	struct	mutex mdev_lock;
+	int	mdev_count;
+	struct	list_head dma_maps;
+	int	vectors;
+	struct	ifcvf_hw vf;
+};
+
+int ifcvf_init_hw(struct ifcvf_hw *hw, struct pci_dev *dev);
+u64 ifcvf_get_features(struct ifcvf_hw *hw);
+int ifcvf_start_hw(struct ifcvf_hw *hw);
+void ifcvf_stop_hw(struct ifcvf_hw *hw);
+void ifcvf_enable_logging(struct ifcvf_hw *hw, u64 log_base, u64 log_size);
+void ifcvf_enable_logging_vf(struct ifcvf_hw *hw, u64 log_base, u64 log_size);
+void ifcvf_disable_logging(struct ifcvf_hw *hw);
+void ifcvf_notify_queue(struct ifcvf_hw *hw, u16 qid);
+void ifcvf_get_linkstatus(struct ifcvf_hw *hw, u8 *is_linkup);
+u8 ifcvf_get_notify_region(struct ifcvf_hw *hw);
+u64 ifcvf_get_queue_notify_off(struct ifcvf_hw *hw, int qid);
+
+#endif /* _IFCVF_H_ */
-- 
2.16.4