diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/pci/controller/vmd.c | 1135 |
1 files changed, 1135 insertions, 0 deletions
diff --git a/drivers/pci/controller/vmd.c b/drivers/pci/controller/vmd.c new file mode 100644 index 0000000000..6ac0afae0c --- /dev/null +++ b/drivers/pci/controller/vmd.c @@ -0,0 +1,1135 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Volume Management Device driver + * Copyright (c) 2015, Intel Corporation. + */ + +#include <linux/device.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/msi.h> +#include <linux/pci.h> +#include <linux/pci-acpi.h> +#include <linux/pci-ecam.h> +#include <linux/srcu.h> +#include <linux/rculist.h> +#include <linux/rcupdate.h> + +#include <asm/irqdomain.h> + +#define VMD_CFGBAR 0 +#define VMD_MEMBAR1 2 +#define VMD_MEMBAR2 4 + +#define PCI_REG_VMCAP 0x40 +#define BUS_RESTRICT_CAP(vmcap) (vmcap & 0x1) +#define PCI_REG_VMCONFIG 0x44 +#define BUS_RESTRICT_CFG(vmcfg) ((vmcfg >> 8) & 0x3) +#define VMCONFIG_MSI_REMAP 0x2 +#define PCI_REG_VMLOCK 0x70 +#define MB2_SHADOW_EN(vmlock) (vmlock & 0x2) + +#define MB2_SHADOW_OFFSET 0x2000 +#define MB2_SHADOW_SIZE 16 + +enum vmd_features { + /* + * Device may contain registers which hint the physical location of the + * membars, in order to allow proper address translation during + * resource assignment to enable guest virtualization + */ + VMD_FEAT_HAS_MEMBAR_SHADOW = (1 << 0), + + /* + * Device may provide root port configuration information which limits + * bus numbering + */ + VMD_FEAT_HAS_BUS_RESTRICTIONS = (1 << 1), + + /* + * Device contains physical location shadow registers in + * vendor-specific capability space + */ + VMD_FEAT_HAS_MEMBAR_SHADOW_VSCAP = (1 << 2), + + /* + * Device may use MSI-X vector 0 for software triggering and will not + * be used for MSI remapping + */ + VMD_FEAT_OFFSET_FIRST_VECTOR = (1 << 3), + + /* + * Device can bypass remapping MSI-X transactions into its MSI-X table, + * avoiding the requirement of a VMD MSI domain for child device + * interrupt handling. + */ + VMD_FEAT_CAN_BYPASS_MSI_REMAP = (1 << 4), + + /* + * Enable ASPM on the PCIE root ports and set the default LTR of the + * storage devices on platforms where these values are not configured by + * BIOS. This is needed for laptops, which require these settings for + * proper power management of the SoC. + */ + VMD_FEAT_BIOS_PM_QUIRK = (1 << 5), +}; + +#define VMD_BIOS_PM_QUIRK_LTR 0x1003 /* 3145728 ns */ + +#define VMD_FEATS_CLIENT (VMD_FEAT_HAS_MEMBAR_SHADOW_VSCAP | \ + VMD_FEAT_HAS_BUS_RESTRICTIONS | \ + VMD_FEAT_OFFSET_FIRST_VECTOR | \ + VMD_FEAT_BIOS_PM_QUIRK) + +static DEFINE_IDA(vmd_instance_ida); + +/* + * Lock for manipulating VMD IRQ lists. + */ +static DEFINE_RAW_SPINLOCK(list_lock); + +/** + * struct vmd_irq - private data to map driver IRQ to the VMD shared vector + * @node: list item for parent traversal. + * @irq: back pointer to parent. + * @enabled: true if driver enabled IRQ + * @virq: the virtual IRQ value provided to the requesting driver. + * + * Every MSI/MSI-X IRQ requested for a device in a VMD domain will be mapped to + * a VMD IRQ using this structure. + */ +struct vmd_irq { + struct list_head node; + struct vmd_irq_list *irq; + bool enabled; + unsigned int virq; +}; + +/** + * struct vmd_irq_list - list of driver requested IRQs mapping to a VMD vector + * @irq_list: the list of irq's the VMD one demuxes to. + * @srcu: SRCU struct for local synchronization. + * @count: number of child IRQs assigned to this vector; used to track + * sharing. + * @virq: The underlying VMD Linux interrupt number + */ +struct vmd_irq_list { + struct list_head irq_list; + struct srcu_struct srcu; + unsigned int count; + unsigned int virq; +}; + +struct vmd_dev { + struct pci_dev *dev; + + spinlock_t cfg_lock; + void __iomem *cfgbar; + + int msix_count; + struct vmd_irq_list *irqs; + + struct pci_sysdata sysdata; + struct resource resources[3]; + struct irq_domain *irq_domain; + struct pci_bus *bus; + u8 busn_start; + u8 first_vec; + char *name; + int instance; +}; + +static inline struct vmd_dev *vmd_from_bus(struct pci_bus *bus) +{ + return container_of(bus->sysdata, struct vmd_dev, sysdata); +} + +static inline unsigned int index_from_irqs(struct vmd_dev *vmd, + struct vmd_irq_list *irqs) +{ + return irqs - vmd->irqs; +} + +/* + * Drivers managing a device in a VMD domain allocate their own IRQs as before, + * but the MSI entry for the hardware it's driving will be programmed with a + * destination ID for the VMD MSI-X table. The VMD muxes interrupts in its + * domain into one of its own, and the VMD driver de-muxes these for the + * handlers sharing that VMD IRQ. The vmd irq_domain provides the operations + * and irq_chip to set this up. + */ +static void vmd_compose_msi_msg(struct irq_data *data, struct msi_msg *msg) +{ + struct vmd_irq *vmdirq = data->chip_data; + struct vmd_irq_list *irq = vmdirq->irq; + struct vmd_dev *vmd = irq_data_get_irq_handler_data(data); + + memset(msg, 0, sizeof(*msg)); + msg->address_hi = X86_MSI_BASE_ADDRESS_HIGH; + msg->arch_addr_lo.base_address = X86_MSI_BASE_ADDRESS_LOW; + msg->arch_addr_lo.destid_0_7 = index_from_irqs(vmd, irq); +} + +/* + * We rely on MSI_FLAG_USE_DEF_CHIP_OPS to set the IRQ mask/unmask ops. + */ +static void vmd_irq_enable(struct irq_data *data) +{ + struct vmd_irq *vmdirq = data->chip_data; + unsigned long flags; + + raw_spin_lock_irqsave(&list_lock, flags); + WARN_ON(vmdirq->enabled); + list_add_tail_rcu(&vmdirq->node, &vmdirq->irq->irq_list); + vmdirq->enabled = true; + raw_spin_unlock_irqrestore(&list_lock, flags); + + data->chip->irq_unmask(data); +} + +static void vmd_irq_disable(struct irq_data *data) +{ + struct vmd_irq *vmdirq = data->chip_data; + unsigned long flags; + + data->chip->irq_mask(data); + + raw_spin_lock_irqsave(&list_lock, flags); + if (vmdirq->enabled) { + list_del_rcu(&vmdirq->node); + vmdirq->enabled = false; + } + raw_spin_unlock_irqrestore(&list_lock, flags); +} + +/* + * XXX: Stubbed until we develop acceptable way to not create conflicts with + * other devices sharing the same vector. + */ +static int vmd_irq_set_affinity(struct irq_data *data, + const struct cpumask *dest, bool force) +{ + return -EINVAL; +} + +static struct irq_chip vmd_msi_controller = { + .name = "VMD-MSI", + .irq_enable = vmd_irq_enable, + .irq_disable = vmd_irq_disable, + .irq_compose_msi_msg = vmd_compose_msi_msg, + .irq_set_affinity = vmd_irq_set_affinity, +}; + +static irq_hw_number_t vmd_get_hwirq(struct msi_domain_info *info, + msi_alloc_info_t *arg) +{ + return 0; +} + +/* + * XXX: We can be even smarter selecting the best IRQ once we solve the + * affinity problem. + */ +static struct vmd_irq_list *vmd_next_irq(struct vmd_dev *vmd, struct msi_desc *desc) +{ + unsigned long flags; + int i, best; + + if (vmd->msix_count == 1 + vmd->first_vec) + return &vmd->irqs[vmd->first_vec]; + + /* + * White list for fast-interrupt handlers. All others will share the + * "slow" interrupt vector. + */ + switch (msi_desc_to_pci_dev(desc)->class) { + case PCI_CLASS_STORAGE_EXPRESS: + break; + default: + return &vmd->irqs[vmd->first_vec]; + } + + raw_spin_lock_irqsave(&list_lock, flags); + best = vmd->first_vec + 1; + for (i = best; i < vmd->msix_count; i++) + if (vmd->irqs[i].count < vmd->irqs[best].count) + best = i; + vmd->irqs[best].count++; + raw_spin_unlock_irqrestore(&list_lock, flags); + + return &vmd->irqs[best]; +} + +static int vmd_msi_init(struct irq_domain *domain, struct msi_domain_info *info, + unsigned int virq, irq_hw_number_t hwirq, + msi_alloc_info_t *arg) +{ + struct msi_desc *desc = arg->desc; + struct vmd_dev *vmd = vmd_from_bus(msi_desc_to_pci_dev(desc)->bus); + struct vmd_irq *vmdirq = kzalloc(sizeof(*vmdirq), GFP_KERNEL); + + if (!vmdirq) + return -ENOMEM; + + INIT_LIST_HEAD(&vmdirq->node); + vmdirq->irq = vmd_next_irq(vmd, desc); + vmdirq->virq = virq; + + irq_domain_set_info(domain, virq, vmdirq->irq->virq, info->chip, vmdirq, + handle_untracked_irq, vmd, NULL); + return 0; +} + +static void vmd_msi_free(struct irq_domain *domain, + struct msi_domain_info *info, unsigned int virq) +{ + struct vmd_irq *vmdirq = irq_get_chip_data(virq); + unsigned long flags; + + synchronize_srcu(&vmdirq->irq->srcu); + + /* XXX: Potential optimization to rebalance */ + raw_spin_lock_irqsave(&list_lock, flags); + vmdirq->irq->count--; + raw_spin_unlock_irqrestore(&list_lock, flags); + + kfree(vmdirq); +} + +static int vmd_msi_prepare(struct irq_domain *domain, struct device *dev, + int nvec, msi_alloc_info_t *arg) +{ + struct pci_dev *pdev = to_pci_dev(dev); + struct vmd_dev *vmd = vmd_from_bus(pdev->bus); + + if (nvec > vmd->msix_count) + return vmd->msix_count; + + memset(arg, 0, sizeof(*arg)); + return 0; +} + +static void vmd_set_desc(msi_alloc_info_t *arg, struct msi_desc *desc) +{ + arg->desc = desc; +} + +static struct msi_domain_ops vmd_msi_domain_ops = { + .get_hwirq = vmd_get_hwirq, + .msi_init = vmd_msi_init, + .msi_free = vmd_msi_free, + .msi_prepare = vmd_msi_prepare, + .set_desc = vmd_set_desc, +}; + +static struct msi_domain_info vmd_msi_domain_info = { + .flags = MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS | + MSI_FLAG_PCI_MSIX, + .ops = &vmd_msi_domain_ops, + .chip = &vmd_msi_controller, +}; + +static void vmd_set_msi_remapping(struct vmd_dev *vmd, bool enable) +{ + u16 reg; + + pci_read_config_word(vmd->dev, PCI_REG_VMCONFIG, ®); + reg = enable ? (reg & ~VMCONFIG_MSI_REMAP) : + (reg | VMCONFIG_MSI_REMAP); + pci_write_config_word(vmd->dev, PCI_REG_VMCONFIG, reg); +} + +static int vmd_create_irq_domain(struct vmd_dev *vmd) +{ + struct fwnode_handle *fn; + + fn = irq_domain_alloc_named_id_fwnode("VMD-MSI", vmd->sysdata.domain); + if (!fn) + return -ENODEV; + + vmd->irq_domain = pci_msi_create_irq_domain(fn, &vmd_msi_domain_info, NULL); + if (!vmd->irq_domain) { + irq_domain_free_fwnode(fn); + return -ENODEV; + } + + return 0; +} + +static void vmd_remove_irq_domain(struct vmd_dev *vmd) +{ + /* + * Some production BIOS won't enable remapping between soft reboots. + * Ensure remapping is restored before unloading the driver. + */ + if (!vmd->msix_count) + vmd_set_msi_remapping(vmd, true); + + if (vmd->irq_domain) { + struct fwnode_handle *fn = vmd->irq_domain->fwnode; + + irq_domain_remove(vmd->irq_domain); + irq_domain_free_fwnode(fn); + } +} + +static void __iomem *vmd_cfg_addr(struct vmd_dev *vmd, struct pci_bus *bus, + unsigned int devfn, int reg, int len) +{ + unsigned int busnr_ecam = bus->number - vmd->busn_start; + u32 offset = PCIE_ECAM_OFFSET(busnr_ecam, devfn, reg); + + if (offset + len >= resource_size(&vmd->dev->resource[VMD_CFGBAR])) + return NULL; + + return vmd->cfgbar + offset; +} + +/* + * CPU may deadlock if config space is not serialized on some versions of this + * hardware, so all config space access is done under a spinlock. + */ +static int vmd_pci_read(struct pci_bus *bus, unsigned int devfn, int reg, + int len, u32 *value) +{ + struct vmd_dev *vmd = vmd_from_bus(bus); + void __iomem *addr = vmd_cfg_addr(vmd, bus, devfn, reg, len); + unsigned long flags; + int ret = 0; + + if (!addr) + return -EFAULT; + + spin_lock_irqsave(&vmd->cfg_lock, flags); + switch (len) { + case 1: + *value = readb(addr); + break; + case 2: + *value = readw(addr); + break; + case 4: + *value = readl(addr); + break; + default: + ret = -EINVAL; + break; + } + spin_unlock_irqrestore(&vmd->cfg_lock, flags); + return ret; +} + +/* + * VMD h/w converts non-posted config writes to posted memory writes. The + * read-back in this function forces the completion so it returns only after + * the config space was written, as expected. + */ +static int vmd_pci_write(struct pci_bus *bus, unsigned int devfn, int reg, + int len, u32 value) +{ + struct vmd_dev *vmd = vmd_from_bus(bus); + void __iomem *addr = vmd_cfg_addr(vmd, bus, devfn, reg, len); + unsigned long flags; + int ret = 0; + + if (!addr) + return -EFAULT; + + spin_lock_irqsave(&vmd->cfg_lock, flags); + switch (len) { + case 1: + writeb(value, addr); + readb(addr); + break; + case 2: + writew(value, addr); + readw(addr); + break; + case 4: + writel(value, addr); + readl(addr); + break; + default: + ret = -EINVAL; + break; + } + spin_unlock_irqrestore(&vmd->cfg_lock, flags); + return ret; +} + +static struct pci_ops vmd_ops = { + .read = vmd_pci_read, + .write = vmd_pci_write, +}; + +#ifdef CONFIG_ACPI +static struct acpi_device *vmd_acpi_find_companion(struct pci_dev *pci_dev) +{ + struct pci_host_bridge *bridge; + u32 busnr, addr; + + if (pci_dev->bus->ops != &vmd_ops) + return NULL; + + bridge = pci_find_host_bridge(pci_dev->bus); + busnr = pci_dev->bus->number - bridge->bus->number; + /* + * The address computation below is only applicable to relative bus + * numbers below 32. + */ + if (busnr > 31) + return NULL; + + addr = (busnr << 24) | ((u32)pci_dev->devfn << 16) | 0x8000FFFFU; + + dev_dbg(&pci_dev->dev, "Looking for ACPI companion (address 0x%x)\n", + addr); + + return acpi_find_child_device(ACPI_COMPANION(bridge->dev.parent), addr, + false); +} + +static bool hook_installed; + +static void vmd_acpi_begin(void) +{ + if (pci_acpi_set_companion_lookup_hook(vmd_acpi_find_companion)) + return; + + hook_installed = true; +} + +static void vmd_acpi_end(void) +{ + if (!hook_installed) + return; + + pci_acpi_clear_companion_lookup_hook(); + hook_installed = false; +} +#else +static inline void vmd_acpi_begin(void) { } +static inline void vmd_acpi_end(void) { } +#endif /* CONFIG_ACPI */ + +static void vmd_domain_reset(struct vmd_dev *vmd) +{ + u16 bus, max_buses = resource_size(&vmd->resources[0]); + u8 dev, functions, fn, hdr_type; + char __iomem *base; + + for (bus = 0; bus < max_buses; bus++) { + for (dev = 0; dev < 32; dev++) { + base = vmd->cfgbar + PCIE_ECAM_OFFSET(bus, + PCI_DEVFN(dev, 0), 0); + + hdr_type = readb(base + PCI_HEADER_TYPE); + + functions = (hdr_type & 0x80) ? 8 : 1; + for (fn = 0; fn < functions; fn++) { + base = vmd->cfgbar + PCIE_ECAM_OFFSET(bus, + PCI_DEVFN(dev, fn), 0); + + hdr_type = readb(base + PCI_HEADER_TYPE) & + PCI_HEADER_TYPE_MASK; + + if (hdr_type != PCI_HEADER_TYPE_BRIDGE || + (readw(base + PCI_CLASS_DEVICE) != + PCI_CLASS_BRIDGE_PCI)) + continue; + + /* + * Temporarily disable the I/O range before updating + * PCI_IO_BASE. + */ + writel(0x0000ffff, base + PCI_IO_BASE_UPPER16); + /* Update lower 16 bits of I/O base/limit */ + writew(0x00f0, base + PCI_IO_BASE); + /* Update upper 16 bits of I/O base/limit */ + writel(0, base + PCI_IO_BASE_UPPER16); + + /* MMIO Base/Limit */ + writel(0x0000fff0, base + PCI_MEMORY_BASE); + + /* Prefetchable MMIO Base/Limit */ + writel(0, base + PCI_PREF_LIMIT_UPPER32); + writel(0x0000fff0, base + PCI_PREF_MEMORY_BASE); + writel(0xffffffff, base + PCI_PREF_BASE_UPPER32); + } + } + } +} + +static void vmd_attach_resources(struct vmd_dev *vmd) +{ + vmd->dev->resource[VMD_MEMBAR1].child = &vmd->resources[1]; + vmd->dev->resource[VMD_MEMBAR2].child = &vmd->resources[2]; +} + +static void vmd_detach_resources(struct vmd_dev *vmd) +{ + vmd->dev->resource[VMD_MEMBAR1].child = NULL; + vmd->dev->resource[VMD_MEMBAR2].child = NULL; +} + +/* + * VMD domains start at 0x10000 to not clash with ACPI _SEG domains. + * Per ACPI r6.0, sec 6.5.6, _SEG returns an integer, of which the lower + * 16 bits are the PCI Segment Group (domain) number. Other bits are + * currently reserved. + */ +static int vmd_find_free_domain(void) +{ + int domain = 0xffff; + struct pci_bus *bus = NULL; + + while ((bus = pci_find_next_bus(bus)) != NULL) + domain = max_t(int, domain, pci_domain_nr(bus)); + return domain + 1; +} + +static int vmd_get_phys_offsets(struct vmd_dev *vmd, bool native_hint, + resource_size_t *offset1, + resource_size_t *offset2) +{ + struct pci_dev *dev = vmd->dev; + u64 phys1, phys2; + + if (native_hint) { + u32 vmlock; + int ret; + + ret = pci_read_config_dword(dev, PCI_REG_VMLOCK, &vmlock); + if (ret || PCI_POSSIBLE_ERROR(vmlock)) + return -ENODEV; + + if (MB2_SHADOW_EN(vmlock)) { + void __iomem *membar2; + + membar2 = pci_iomap(dev, VMD_MEMBAR2, 0); + if (!membar2) + return -ENOMEM; + phys1 = readq(membar2 + MB2_SHADOW_OFFSET); + phys2 = readq(membar2 + MB2_SHADOW_OFFSET + 8); + pci_iounmap(dev, membar2); + } else + return 0; + } else { + /* Hypervisor-Emulated Vendor-Specific Capability */ + int pos = pci_find_capability(dev, PCI_CAP_ID_VNDR); + u32 reg, regu; + + pci_read_config_dword(dev, pos + 4, ®); + + /* "SHDW" */ + if (pos && reg == 0x53484457) { + pci_read_config_dword(dev, pos + 8, ®); + pci_read_config_dword(dev, pos + 12, ®u); + phys1 = (u64) regu << 32 | reg; + + pci_read_config_dword(dev, pos + 16, ®); + pci_read_config_dword(dev, pos + 20, ®u); + phys2 = (u64) regu << 32 | reg; + } else + return 0; + } + + *offset1 = dev->resource[VMD_MEMBAR1].start - + (phys1 & PCI_BASE_ADDRESS_MEM_MASK); + *offset2 = dev->resource[VMD_MEMBAR2].start - + (phys2 & PCI_BASE_ADDRESS_MEM_MASK); + + return 0; +} + +static int vmd_get_bus_number_start(struct vmd_dev *vmd) +{ + struct pci_dev *dev = vmd->dev; + u16 reg; + + pci_read_config_word(dev, PCI_REG_VMCAP, ®); + if (BUS_RESTRICT_CAP(reg)) { + pci_read_config_word(dev, PCI_REG_VMCONFIG, ®); + + switch (BUS_RESTRICT_CFG(reg)) { + case 0: + vmd->busn_start = 0; + break; + case 1: + vmd->busn_start = 128; + break; + case 2: + vmd->busn_start = 224; + break; + default: + pci_err(dev, "Unknown Bus Offset Setting (%d)\n", + BUS_RESTRICT_CFG(reg)); + return -ENODEV; + } + } + + return 0; +} + +static irqreturn_t vmd_irq(int irq, void *data) +{ + struct vmd_irq_list *irqs = data; + struct vmd_irq *vmdirq; + int idx; + + idx = srcu_read_lock(&irqs->srcu); + list_for_each_entry_rcu(vmdirq, &irqs->irq_list, node) + generic_handle_irq(vmdirq->virq); + srcu_read_unlock(&irqs->srcu, idx); + + return IRQ_HANDLED; +} + +static int vmd_alloc_irqs(struct vmd_dev *vmd) +{ + struct pci_dev *dev = vmd->dev; + int i, err; + + vmd->msix_count = pci_msix_vec_count(dev); + if (vmd->msix_count < 0) + return -ENODEV; + + vmd->msix_count = pci_alloc_irq_vectors(dev, vmd->first_vec + 1, + vmd->msix_count, PCI_IRQ_MSIX); + if (vmd->msix_count < 0) + return vmd->msix_count; + + vmd->irqs = devm_kcalloc(&dev->dev, vmd->msix_count, sizeof(*vmd->irqs), + GFP_KERNEL); + if (!vmd->irqs) + return -ENOMEM; + + for (i = 0; i < vmd->msix_count; i++) { + err = init_srcu_struct(&vmd->irqs[i].srcu); + if (err) + return err; + + INIT_LIST_HEAD(&vmd->irqs[i].irq_list); + vmd->irqs[i].virq = pci_irq_vector(dev, i); + err = devm_request_irq(&dev->dev, vmd->irqs[i].virq, + vmd_irq, IRQF_NO_THREAD, + vmd->name, &vmd->irqs[i]); + if (err) + return err; + } + + return 0; +} + +/* + * Since VMD is an aperture to regular PCIe root ports, only allow it to + * control features that the OS is allowed to control on the physical PCI bus. + */ +static void vmd_copy_host_bridge_flags(struct pci_host_bridge *root_bridge, + struct pci_host_bridge *vmd_bridge) +{ + vmd_bridge->native_pcie_hotplug = root_bridge->native_pcie_hotplug; + vmd_bridge->native_shpc_hotplug = root_bridge->native_shpc_hotplug; + vmd_bridge->native_aer = root_bridge->native_aer; + vmd_bridge->native_pme = root_bridge->native_pme; + vmd_bridge->native_ltr = root_bridge->native_ltr; + vmd_bridge->native_dpc = root_bridge->native_dpc; +} + +/* + * Enable ASPM and LTR settings on devices that aren't configured by BIOS. + */ +static int vmd_pm_enable_quirk(struct pci_dev *pdev, void *userdata) +{ + unsigned long features = *(unsigned long *)userdata; + u16 ltr = VMD_BIOS_PM_QUIRK_LTR; + u32 ltr_reg; + int pos; + + if (!(features & VMD_FEAT_BIOS_PM_QUIRK)) + return 0; + + pci_enable_link_state_locked(pdev, PCIE_LINK_STATE_ALL); + + pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_LTR); + if (!pos) + return 0; + + /* + * Skip if the max snoop LTR is non-zero, indicating BIOS has set it + * so the LTR quirk is not needed. + */ + pci_read_config_dword(pdev, pos + PCI_LTR_MAX_SNOOP_LAT, <r_reg); + if (!!(ltr_reg & (PCI_LTR_VALUE_MASK | PCI_LTR_SCALE_MASK))) + return 0; + + /* + * Set the default values to the maximum required by the platform to + * allow the deepest power management savings. Write as a DWORD where + * the lower word is the max snoop latency and the upper word is the + * max non-snoop latency. + */ + ltr_reg = (ltr << 16) | ltr; + pci_write_config_dword(pdev, pos + PCI_LTR_MAX_SNOOP_LAT, ltr_reg); + pci_info(pdev, "VMD: Default LTR value set by driver\n"); + + return 0; +} + +static int vmd_enable_domain(struct vmd_dev *vmd, unsigned long features) +{ + struct pci_sysdata *sd = &vmd->sysdata; + struct resource *res; + u32 upper_bits; + unsigned long flags; + LIST_HEAD(resources); + resource_size_t offset[2] = {0}; + resource_size_t membar2_offset = 0x2000; + struct pci_bus *child; + struct pci_dev *dev; + int ret; + + /* + * Shadow registers may exist in certain VMD device ids which allow + * guests to correctly assign host physical addresses to the root ports + * and child devices. These registers will either return the host value + * or 0, depending on an enable bit in the VMD device. + */ + if (features & VMD_FEAT_HAS_MEMBAR_SHADOW) { + membar2_offset = MB2_SHADOW_OFFSET + MB2_SHADOW_SIZE; + ret = vmd_get_phys_offsets(vmd, true, &offset[0], &offset[1]); + if (ret) + return ret; + } else if (features & VMD_FEAT_HAS_MEMBAR_SHADOW_VSCAP) { + ret = vmd_get_phys_offsets(vmd, false, &offset[0], &offset[1]); + if (ret) + return ret; + } + + /* + * Certain VMD devices may have a root port configuration option which + * limits the bus range to between 0-127, 128-255, or 224-255 + */ + if (features & VMD_FEAT_HAS_BUS_RESTRICTIONS) { + ret = vmd_get_bus_number_start(vmd); + if (ret) + return ret; + } + + res = &vmd->dev->resource[VMD_CFGBAR]; + vmd->resources[0] = (struct resource) { + .name = "VMD CFGBAR", + .start = vmd->busn_start, + .end = vmd->busn_start + (resource_size(res) >> 20) - 1, + .flags = IORESOURCE_BUS | IORESOURCE_PCI_FIXED, + }; + + /* + * If the window is below 4GB, clear IORESOURCE_MEM_64 so we can + * put 32-bit resources in the window. + * + * There's no hardware reason why a 64-bit window *couldn't* + * contain a 32-bit resource, but pbus_size_mem() computes the + * bridge window size assuming a 64-bit window will contain no + * 32-bit resources. __pci_assign_resource() enforces that + * artificial restriction to make sure everything will fit. + * + * The only way we could use a 64-bit non-prefetchable MEMBAR is + * if its address is <4GB so that we can convert it to a 32-bit + * resource. To be visible to the host OS, all VMD endpoints must + * be initially configured by platform BIOS, which includes setting + * up these resources. We can assume the device is configured + * according to the platform needs. + */ + res = &vmd->dev->resource[VMD_MEMBAR1]; + upper_bits = upper_32_bits(res->end); + flags = res->flags & ~IORESOURCE_SIZEALIGN; + if (!upper_bits) + flags &= ~IORESOURCE_MEM_64; + vmd->resources[1] = (struct resource) { + .name = "VMD MEMBAR1", + .start = res->start, + .end = res->end, + .flags = flags, + .parent = res, + }; + + res = &vmd->dev->resource[VMD_MEMBAR2]; + upper_bits = upper_32_bits(res->end); + flags = res->flags & ~IORESOURCE_SIZEALIGN; + if (!upper_bits) + flags &= ~IORESOURCE_MEM_64; + vmd->resources[2] = (struct resource) { + .name = "VMD MEMBAR2", + .start = res->start + membar2_offset, + .end = res->end, + .flags = flags, + .parent = res, + }; + + sd->vmd_dev = vmd->dev; + sd->domain = vmd_find_free_domain(); + if (sd->domain < 0) + return sd->domain; + + sd->node = pcibus_to_node(vmd->dev->bus); + + /* + * Currently MSI remapping must be enabled in guest passthrough mode + * due to some missing interrupt remapping plumbing. This is probably + * acceptable because the guest is usually CPU-limited and MSI + * remapping doesn't become a performance bottleneck. + */ + if (!(features & VMD_FEAT_CAN_BYPASS_MSI_REMAP) || + offset[0] || offset[1]) { + ret = vmd_alloc_irqs(vmd); + if (ret) + return ret; + + vmd_set_msi_remapping(vmd, true); + + ret = vmd_create_irq_domain(vmd); + if (ret) + return ret; + + /* + * Override the IRQ domain bus token so the domain can be + * distinguished from a regular PCI/MSI domain. + */ + irq_domain_update_bus_token(vmd->irq_domain, DOMAIN_BUS_VMD_MSI); + } else { + vmd_set_msi_remapping(vmd, false); + } + + pci_add_resource(&resources, &vmd->resources[0]); + pci_add_resource_offset(&resources, &vmd->resources[1], offset[0]); + pci_add_resource_offset(&resources, &vmd->resources[2], offset[1]); + + vmd->bus = pci_create_root_bus(&vmd->dev->dev, vmd->busn_start, + &vmd_ops, sd, &resources); + if (!vmd->bus) { + pci_free_resource_list(&resources); + vmd_remove_irq_domain(vmd); + return -ENODEV; + } + + vmd_copy_host_bridge_flags(pci_find_host_bridge(vmd->dev->bus), + to_pci_host_bridge(vmd->bus->bridge)); + + vmd_attach_resources(vmd); + if (vmd->irq_domain) + dev_set_msi_domain(&vmd->bus->dev, vmd->irq_domain); + else + dev_set_msi_domain(&vmd->bus->dev, + dev_get_msi_domain(&vmd->dev->dev)); + + vmd_acpi_begin(); + + pci_scan_child_bus(vmd->bus); + vmd_domain_reset(vmd); + + /* When Intel VMD is enabled, the OS does not discover the Root Ports + * owned by Intel VMD within the MMCFG space. pci_reset_bus() applies + * a reset to the parent of the PCI device supplied as argument. This + * is why we pass a child device, so the reset can be triggered at + * the Intel bridge level and propagated to all the children in the + * hierarchy. + */ + list_for_each_entry(child, &vmd->bus->children, node) { + if (!list_empty(&child->devices)) { + dev = list_first_entry(&child->devices, + struct pci_dev, bus_list); + ret = pci_reset_bus(dev); + if (ret) + pci_warn(dev, "can't reset device: %d\n", ret); + + break; + } + } + + pci_assign_unassigned_bus_resources(vmd->bus); + + pci_walk_bus(vmd->bus, vmd_pm_enable_quirk, &features); + + /* + * VMD root buses are virtual and don't return true on pci_is_pcie() + * and will fail pcie_bus_configure_settings() early. It can instead be + * run on each of the real root ports. + */ + list_for_each_entry(child, &vmd->bus->children, node) + pcie_bus_configure_settings(child); + + pci_bus_add_devices(vmd->bus); + + vmd_acpi_end(); + + WARN(sysfs_create_link(&vmd->dev->dev.kobj, &vmd->bus->dev.kobj, + "domain"), "Can't create symlink to domain\n"); + return 0; +} + +static int vmd_probe(struct pci_dev *dev, const struct pci_device_id *id) +{ + unsigned long features = (unsigned long) id->driver_data; + struct vmd_dev *vmd; + int err; + + if (resource_size(&dev->resource[VMD_CFGBAR]) < (1 << 20)) + return -ENOMEM; + + vmd = devm_kzalloc(&dev->dev, sizeof(*vmd), GFP_KERNEL); + if (!vmd) + return -ENOMEM; + + vmd->dev = dev; + vmd->instance = ida_simple_get(&vmd_instance_ida, 0, 0, GFP_KERNEL); + if (vmd->instance < 0) + return vmd->instance; + + vmd->name = devm_kasprintf(&dev->dev, GFP_KERNEL, "vmd%d", + vmd->instance); + if (!vmd->name) { + err = -ENOMEM; + goto out_release_instance; + } + + err = pcim_enable_device(dev); + if (err < 0) + goto out_release_instance; + + vmd->cfgbar = pcim_iomap(dev, VMD_CFGBAR, 0); + if (!vmd->cfgbar) { + err = -ENOMEM; + goto out_release_instance; + } + + pci_set_master(dev); + if (dma_set_mask_and_coherent(&dev->dev, DMA_BIT_MASK(64)) && + dma_set_mask_and_coherent(&dev->dev, DMA_BIT_MASK(32))) { + err = -ENODEV; + goto out_release_instance; + } + + if (features & VMD_FEAT_OFFSET_FIRST_VECTOR) + vmd->first_vec = 1; + + spin_lock_init(&vmd->cfg_lock); + pci_set_drvdata(dev, vmd); + err = vmd_enable_domain(vmd, features); + if (err) + goto out_release_instance; + + dev_info(&vmd->dev->dev, "Bound to PCI domain %04x\n", + vmd->sysdata.domain); + return 0; + + out_release_instance: + ida_simple_remove(&vmd_instance_ida, vmd->instance); + return err; +} + +static void vmd_cleanup_srcu(struct vmd_dev *vmd) +{ + int i; + + for (i = 0; i < vmd->msix_count; i++) + cleanup_srcu_struct(&vmd->irqs[i].srcu); +} + +static void vmd_remove(struct pci_dev *dev) +{ + struct vmd_dev *vmd = pci_get_drvdata(dev); + + sysfs_remove_link(&vmd->dev->dev.kobj, "domain"); + pci_stop_root_bus(vmd->bus); + pci_remove_root_bus(vmd->bus); + vmd_cleanup_srcu(vmd); + vmd_detach_resources(vmd); + vmd_remove_irq_domain(vmd); + ida_simple_remove(&vmd_instance_ida, vmd->instance); +} + +static void vmd_shutdown(struct pci_dev *dev) +{ + struct vmd_dev *vmd = pci_get_drvdata(dev); + + vmd_remove_irq_domain(vmd); +} + +#ifdef CONFIG_PM_SLEEP +static int vmd_suspend(struct device *dev) +{ + struct pci_dev *pdev = to_pci_dev(dev); + struct vmd_dev *vmd = pci_get_drvdata(pdev); + int i; + + for (i = 0; i < vmd->msix_count; i++) + devm_free_irq(dev, vmd->irqs[i].virq, &vmd->irqs[i]); + + return 0; +} + +static int vmd_resume(struct device *dev) +{ + struct pci_dev *pdev = to_pci_dev(dev); + struct vmd_dev *vmd = pci_get_drvdata(pdev); + int err, i; + + if (vmd->irq_domain) + vmd_set_msi_remapping(vmd, true); + else + vmd_set_msi_remapping(vmd, false); + + for (i = 0; i < vmd->msix_count; i++) { + err = devm_request_irq(dev, vmd->irqs[i].virq, + vmd_irq, IRQF_NO_THREAD, + vmd->name, &vmd->irqs[i]); + if (err) + return err; + } + + return 0; +} +#endif +static SIMPLE_DEV_PM_OPS(vmd_dev_pm_ops, vmd_suspend, vmd_resume); + +static const struct pci_device_id vmd_ids[] = { + {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_VMD_201D), + .driver_data = VMD_FEAT_HAS_MEMBAR_SHADOW_VSCAP,}, + {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_VMD_28C0), + .driver_data = VMD_FEAT_HAS_MEMBAR_SHADOW | + VMD_FEAT_HAS_BUS_RESTRICTIONS | + VMD_FEAT_CAN_BYPASS_MSI_REMAP,}, + {PCI_VDEVICE(INTEL, 0x467f), + .driver_data = VMD_FEATS_CLIENT,}, + {PCI_VDEVICE(INTEL, 0x4c3d), + .driver_data = VMD_FEATS_CLIENT,}, + {PCI_VDEVICE(INTEL, 0xa77f), + .driver_data = VMD_FEATS_CLIENT,}, + {PCI_VDEVICE(INTEL, 0x7d0b), + .driver_data = VMD_FEATS_CLIENT,}, + {PCI_VDEVICE(INTEL, 0xad0b), + .driver_data = VMD_FEATS_CLIENT,}, + {PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_VMD_9A0B), + .driver_data = VMD_FEATS_CLIENT,}, + {0,} +}; +MODULE_DEVICE_TABLE(pci, vmd_ids); + +static struct pci_driver vmd_drv = { + .name = "vmd", + .id_table = vmd_ids, + .probe = vmd_probe, + .remove = vmd_remove, + .shutdown = vmd_shutdown, + .driver = { + .pm = &vmd_dev_pm_ops, + }, +}; +module_pci_driver(vmd_drv); + +MODULE_AUTHOR("Intel Corporation"); +MODULE_LICENSE("GPL v2"); +MODULE_VERSION("0.6"); |