acrn-hypervisor/devicemodel/hw/pci/ptm.c

212 lines
6.8 KiB
C

/*
* Copyright (C) 2021-2022 Intel Corporation.
*
* SPDX-License-Identifier: BSD-3-Clause
*
*/
#include <errno.h>
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/queue.h>
#include "pcireg.h"
#include "pciaccess.h"
#include "pci_core.h"
#include "ptm.h"
#include "passthru.h"
#include "pci_util.h"
#include "vmmapi.h"
#include "acrn_common.h"
#define PTM_ROOT_PORT_VENDOR 0x8086U
#define PTM_ROOT_PORT_DEVICE 0x9d14U
/* PTM capability register ID*/
#define PCIZ_PTM 0x1fU
/* PTM register Definitions */
/* PTM capability register */
#define PCIR_PTM_CAP 0x04U
#define PCIM_PTM_CAP_REQ 0x01U /* Requestor capable */
#define PCIM_PTM_CAP_ROOT 0x4U /* Root capable */
#define PCIM_PTM_GRANULARITY 0xFF00 /* Clock granularity */
/* PTM control register */
#define PCIR_PTM_CTRL 0x08U
#define PCIM_PTM_CTRL_ENABLE 0x1U /* PTM enable */
#define PCIM_PTM_CTRL_ROOT_SELECT 0x2U /* Root select */
/* virtual root port secondary bus */
static int ptm_root_port_secondary_bus;
/* get ptm capability register value */
static int
get_ptm_reg_value(struct pci_device *pdev, int reg)
{
int pos;
uint32_t reg_val;
pos = pci_find_ext_cap(pdev, PCIZ_PTM);
if (!pos) {
return 0;
}
pci_device_cfg_read_u32(pdev, &reg_val, pos + reg);
pr_notice("<PTM>-%s: device [%x:%x.%x]: ptm pos=0x%x, ptm reg val=0x%x.\n",
__func__, pdev->bus, pdev->dev, pdev->func, pos, reg_val);
return reg_val;
}
/* add virtual root port to hv */
static int
add_vroot_port(struct vmctx *ctx, struct passthru_dev *ptdev, struct pci_device *root_port, int ptm_cap_offset)
{
int error = 0;
int offset = 0;
uint32_t dev_cap = 0;
struct acrn_vdev rp_vdev = {};
struct vrp_config *rp_priv = (struct vrp_config *)&rp_vdev.args;
rp_vdev.id.fields.vendor = PTM_ROOT_PORT_VENDOR;
rp_vdev.id.fields.device = PTM_ROOT_PORT_DEVICE;
// virtual root port takes bdf from its downstream device
rp_vdev.slot = PCI_BDF(ptdev->dev->bus, ptdev->dev->slot, ptdev->dev->func);
rp_priv->phy_bdf = PCI_BDF(root_port->bus, root_port->dev, root_port->func);
rp_priv->primary_bus = ptdev->dev->bus;
rp_priv->secondary_bus = ++ptm_root_port_secondary_bus;
// only passthru device is connected to virtual root port
rp_priv->subordinate_bus = rp_priv->secondary_bus;
rp_priv->ptm_capable = 1;
rp_priv->ptm_cap_offset = ptm_cap_offset;
/* It seems important that passthru device's max payload settings match
* the settings on the native device otherwise passthru device may not work.
* So we have to set vrp's max payload capacity the same as native root port
* otherwise we may accidentally change passthru device's max payload since
* during guest OS's pci enumeration, pass-thru device will renegotiate
* its max payload's setting with vrp.
*/
offset = pci_find_cap(root_port, PCIY_EXPRESS);
pci_device_cfg_read_u32(root_port, &dev_cap, offset + PCIER_DEVICE_CAP);
rp_priv->max_payload = dev_cap & PCIEM_CAP_MAX_PAYLOAD;
pr_info("%s: virtual root port info: vbdf=0x%x, phy_bdf=0x%x, prim_bus=%x, sec_bus=%x, sub_bus=%x, ptm_cpa_offset=0x%x, max_payload=0x%x.\n",
__func__, rp_vdev.slot, rp_priv->phy_bdf, rp_priv->primary_bus, rp_priv->secondary_bus, rp_priv->subordinate_bus,
rp_priv->ptm_cap_offset, rp_priv->max_payload);
error = vm_add_hv_vdev(ctx, &rp_vdev);
if (error) {
pr_err("failed to add virtual root.\n");
return -1;
} else
return rp_priv->secondary_bus;
}
/* Probe whether device and its root port support PTM */
int ptm_probe(struct vmctx *ctx, struct passthru_dev *ptdev, int *vrp_sec_bus)
{
int pos, pcie_type, cap, rp_ptm_offset;
struct pci_device *phys_dev = ptdev->phys_dev;
struct pci_device *rp;
*vrp_sec_bus = 0;
if (!ptdev->pcie_cap) {
pr_err("%s Error: %x:%x.%x is not a pci-e device.\n", __func__,
phys_dev->bus, phys_dev->dev, phys_dev->func);
return -EINVAL;
}
pos = pci_find_ext_cap(phys_dev, PCIZ_PTM);
if (!pos) {
pr_err("%s Error: %x:%x.%x doesn't support ptm.\n", __func__,
phys_dev->bus, phys_dev->dev, phys_dev->func);
return -EINVAL;
}
pcie_type = pci_get_pcie_type(phys_dev);
/* The following sanity checks are based on these assumptions:
* 1. PTM requestor can be enabled on pci ep or rcie.
* 2. HW implements this simple PTM hierarchy: PTM requestor (EP) is
* directly connected to PTM root (root port), or requestor itself is RCIE.
* 3. There is no intermediate nodes (such as switch) in between the PTM
* root and PTM requestor.
* 4. HW only implements one PCI domain in the system and only one PTM
* domain implemented in this PCI domain
*/
if (pcie_type == PCIEM_TYPE_ENDPOINT) {
cap = get_ptm_reg_value(phys_dev, PCIR_PTM_CAP);
if (!(cap & PCIM_PTM_CAP_REQ)) {
pr_err("%s Error: %x:%x.%x must be PTM requestor.\n", __func__,
phys_dev->bus, phys_dev->dev, phys_dev->func);
return -EINVAL;
}
/* Do not support switch */
rp = pci_device_get_parent_bridge(phys_dev);
if ((rp == NULL) || !is_root_port(rp)) {
pr_err("%s Error: Cannot find root port of %x:%x.%x.\n", __func__,
phys_dev->bus, phys_dev->dev, phys_dev->func);
return -ENODEV;
}
/* check whether root port is PTM root-capable */
cap = get_ptm_reg_value(rp, PCIR_PTM_CAP);
if (!(cap & PCIM_PTM_CAP_ROOT)) {
pr_err("%s Error: root port %x:%x.%x of %x:%x.%x is not PTM root capable.\n",
__func__, rp->bus, rp->dev, rp->func,
phys_dev->bus, phys_dev->dev, phys_dev->func);
return -EINVAL;
}
/* TODO: Support multiple PFs device later as it needs to consider to prevent P2P
* attack through ACS or passthrough all PFs together.
*/
if (is_mfdev(phys_dev)) {
pr_err("%s: Failed to enable PTM on root port [%x:%x.%x], multi-func dev is not supported.\n",
__func__, rp->bus, rp->dev, rp->func);
return -EINVAL;
}
/* hv is responsible to ensure that PTM is enabled on hw root port if
* root port is PTM root-capable. If PTM root is not enabled already in physical
* root port before guest launch, guest OS can only enable it in root port's virtual
* config space and PTM may not function as desired so we are not going to allow user
* to enable PTM on pass-thru device.
*/
cap = get_ptm_reg_value(rp, PCIR_PTM_CTRL);
if (!(cap & PCIM_PTM_CTRL_ENABLE) || !(cap & PCIM_PTM_CTRL_ROOT_SELECT)) {
pr_err("%s Warning: guest is not allowed to enable PTM on root port %x:%x.%x.\n",
__func__, rp->bus, rp->dev, rp->func);
return -EINVAL;
}
rp_ptm_offset = pci_find_ext_cap(rp, PCIZ_PTM);
/* add virtual root port */
*vrp_sec_bus = add_vroot_port(ctx, ptdev, rp, rp_ptm_offset);
} else if (pcie_type == PCIEM_TYPE_ROOT_INT_EP) {
/* Do NOT emulate root port if ptm requestor is RCIE */
pr_notice("%s: ptm requestor is root complex integrated device.\n", __func__);
} else {
pr_err("%s Error: PTM can only be enabled on pci root complex integrated device or endpoint device.\n",
__func__);
return -EINVAL;
}
return 0;
}