diff options
Diffstat (limited to 'arch/x86/pci/vmd.c')
| -rw-r--r-- | arch/x86/pci/vmd.c | 723 |
1 files changed, 723 insertions, 0 deletions
diff --git a/arch/x86/pci/vmd.c b/arch/x86/pci/vmd.c new file mode 100644 index 000000000000..d57e48016f15 --- /dev/null +++ b/arch/x86/pci/vmd.c @@ -0,0 +1,723 @@ +/* + * Volume Management Device driver + * Copyright (c) 2015, Intel Corporation. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + */ + +#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/rculist.h> +#include <linux/rcupdate.h> + +#include <asm/irqdomain.h> +#include <asm/device.h> +#include <asm/msi.h> +#include <asm/msidef.h> + +#define VMD_CFGBAR 0 +#define VMD_MEMBAR1 2 +#define VMD_MEMBAR2 4 + +/* + * 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. + * @rcu: RCU callback item for freeing. + * @irq: back pointer to parent. + * @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 rcu_head rcu; + struct vmd_irq_list *irq; + 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. + * @vmd_vector: the h/w IRQ assigned to the VMD. + * @index: index into the VMD MSI-X table; used for message routing. + * @count: number of child IRQs assigned to this vector; used to track + * sharing. + */ +struct vmd_irq_list { + struct list_head irq_list; + struct vmd_dev *vmd; + unsigned int vmd_vector; + unsigned int index; + unsigned int count; +}; + +struct vmd_dev { + struct pci_dev *dev; + + spinlock_t cfg_lock; + char __iomem *cfgbar; + + int msix_count; + struct msix_entry *msix_entries; + struct vmd_irq_list *irqs; + + struct pci_sysdata sysdata; + struct resource resources[3]; + struct irq_domain *irq_domain; + struct pci_bus *bus; + +#ifdef CONFIG_X86_DEV_DMA_OPS + struct dma_map_ops dma_ops; + struct dma_domain dma_domain; +#endif +}; + +static inline struct vmd_dev *vmd_from_bus(struct pci_bus *bus) +{ + return container_of(bus->sysdata, struct vmd_dev, sysdata); +} + +/* + * 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; + + msg->address_hi = MSI_ADDR_BASE_HI; + msg->address_lo = MSI_ADDR_BASE_LO | MSI_ADDR_DEST_ID(irq->index); + msg->data = 0; +} + +/* + * 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; + + raw_spin_lock(&list_lock); + list_add_tail_rcu(&vmdirq->node, &vmdirq->irq->irq_list); + raw_spin_unlock(&list_lock); + + data->chip->irq_unmask(data); +} + +static void vmd_irq_disable(struct irq_data *data) +{ + struct vmd_irq *vmdirq = data->chip_data; + + data->chip->irq_mask(data); + + raw_spin_lock(&list_lock); + list_del_rcu(&vmdirq->node); + raw_spin_unlock(&list_lock); +} + +/* + * 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) +{ + int i, best = 0; + + raw_spin_lock(&list_lock); + for (i = 1; i < vmd->msix_count; i++) + if (vmd->irqs[i].count < vmd->irqs[best].count) + best = i; + vmd->irqs[best].count++; + raw_spin_unlock(&list_lock); + + 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 vmd_dev *vmd = vmd_from_bus(msi_desc_to_pci_dev(arg->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); + vmdirq->virq = virq; + + irq_domain_set_info(domain, virq, vmdirq->irq->vmd_vector, info->chip, + vmdirq, handle_simple_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); + + /* XXX: Potential optimization to rebalance */ + raw_spin_lock(&list_lock); + vmdirq->irq->count--; + raw_spin_unlock(&list_lock); + + kfree_rcu(vmdirq, rcu); +} + +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, +}; + +#ifdef CONFIG_X86_DEV_DMA_OPS +/* + * VMD replaces the requester ID with its own. DMA mappings for devices in a + * VMD domain need to be mapped for the VMD, not the device requiring + * the mapping. + */ +static struct device *to_vmd_dev(struct device *dev) +{ + struct pci_dev *pdev = to_pci_dev(dev); + struct vmd_dev *vmd = vmd_from_bus(pdev->bus); + + return &vmd->dev->dev; +} + +static struct dma_map_ops *vmd_dma_ops(struct device *dev) +{ + return to_vmd_dev(dev)->archdata.dma_ops; +} + +static void *vmd_alloc(struct device *dev, size_t size, dma_addr_t *addr, + gfp_t flag, struct dma_attrs *attrs) +{ + return vmd_dma_ops(dev)->alloc(to_vmd_dev(dev), size, addr, flag, + attrs); +} + +static void vmd_free(struct device *dev, size_t size, void *vaddr, + dma_addr_t addr, struct dma_attrs *attrs) +{ + return vmd_dma_ops(dev)->free(to_vmd_dev(dev), size, vaddr, addr, + attrs); +} + +static int vmd_mmap(struct device *dev, struct vm_area_struct *vma, + void *cpu_addr, dma_addr_t addr, size_t size, + struct dma_attrs *attrs) +{ + return vmd_dma_ops(dev)->mmap(to_vmd_dev(dev), vma, cpu_addr, addr, + size, attrs); +} + +static int vmd_get_sgtable(struct device *dev, struct sg_table *sgt, + void *cpu_addr, dma_addr_t addr, size_t size, + struct dma_attrs *attrs) +{ + return vmd_dma_ops(dev)->get_sgtable(to_vmd_dev(dev), sgt, cpu_addr, + addr, size, attrs); +} + +static dma_addr_t vmd_map_page(struct device *dev, struct page *page, + unsigned long offset, size_t size, + enum dma_data_direction dir, + struct dma_attrs *attrs) +{ + return vmd_dma_ops(dev)->map_page(to_vmd_dev(dev), page, offset, size, + dir, attrs); +} + +static void vmd_unmap_page(struct device *dev, dma_addr_t addr, size_t size, + enum dma_data_direction dir, struct dma_attrs *attrs) +{ + vmd_dma_ops(dev)->unmap_page(to_vmd_dev(dev), addr, size, dir, attrs); +} + +static int vmd_map_sg(struct device *dev, struct scatterlist *sg, int nents, + enum dma_data_direction dir, struct dma_attrs *attrs) +{ + return vmd_dma_ops(dev)->map_sg(to_vmd_dev(dev), sg, nents, dir, attrs); +} + +static void vmd_unmap_sg(struct device *dev, struct scatterlist *sg, int nents, + enum dma_data_direction dir, struct dma_attrs *attrs) +{ + vmd_dma_ops(dev)->unmap_sg(to_vmd_dev(dev), sg, nents, dir, attrs); +} + +static void vmd_sync_single_for_cpu(struct device *dev, dma_addr_t addr, + size_t size, enum dma_data_direction dir) +{ + vmd_dma_ops(dev)->sync_single_for_cpu(to_vmd_dev(dev), addr, size, dir); +} + +static void vmd_sync_single_for_device(struct device *dev, dma_addr_t addr, + size_t size, enum dma_data_direction dir) +{ + vmd_dma_ops(dev)->sync_single_for_device(to_vmd_dev(dev), addr, size, + dir); +} + +static void vmd_sync_sg_for_cpu(struct device *dev, struct scatterlist *sg, + int nents, enum dma_data_direction dir) +{ + vmd_dma_ops(dev)->sync_sg_for_cpu(to_vmd_dev(dev), sg, nents, dir); +} + +static void vmd_sync_sg_for_device(struct device *dev, struct scatterlist *sg, + int nents, enum dma_data_direction dir) +{ + vmd_dma_ops(dev)->sync_sg_for_device(to_vmd_dev(dev), sg, nents, dir); +} + +static int vmd_mapping_error(struct device *dev, dma_addr_t addr) +{ + return vmd_dma_ops(dev)->mapping_error(to_vmd_dev(dev), addr); +} + +static int vmd_dma_supported(struct device *dev, u64 mask) +{ + return vmd_dma_ops(dev)->dma_supported(to_vmd_dev(dev), mask); +} + +#ifdef ARCH_HAS_DMA_GET_REQUIRED_MASK +static u64 vmd_get_required_mask(struct device *dev) +{ + return vmd_dma_ops(dev)->get_required_mask(to_vmd_dev(dev)); +} +#endif + +static void vmd_teardown_dma_ops(struct vmd_dev *vmd) +{ + struct dma_domain *domain = &vmd->dma_domain; + + if (vmd->dev->dev.archdata.dma_ops) + del_dma_domain(domain); +} + +#define ASSIGN_VMD_DMA_OPS(source, dest, fn) \ + do { \ + if (source->fn) \ + dest->fn = vmd_##fn; \ + } while (0) + +static void vmd_setup_dma_ops(struct vmd_dev *vmd) +{ + const struct dma_map_ops *source = vmd->dev->dev.archdata.dma_ops; + struct dma_map_ops *dest = &vmd->dma_ops; + struct dma_domain *domain = &vmd->dma_domain; + + domain->domain_nr = vmd->sysdata.domain; + domain->dma_ops = dest; + + if (!source) + return; + ASSIGN_VMD_DMA_OPS(source, dest, alloc); + ASSIGN_VMD_DMA_OPS(source, dest, free); + ASSIGN_VMD_DMA_OPS(source, dest, mmap); + ASSIGN_VMD_DMA_OPS(source, dest, get_sgtable); + ASSIGN_VMD_DMA_OPS(source, dest, map_page); + ASSIGN_VMD_DMA_OPS(source, dest, unmap_page); + ASSIGN_VMD_DMA_OPS(source, dest, map_sg); + ASSIGN_VMD_DMA_OPS(source, dest, unmap_sg); + ASSIGN_VMD_DMA_OPS(source, dest, sync_single_for_cpu); + ASSIGN_VMD_DMA_OPS(source, dest, sync_single_for_device); + ASSIGN_VMD_DMA_OPS(source, dest, sync_sg_for_cpu); + ASSIGN_VMD_DMA_OPS(source, dest, sync_sg_for_device); + ASSIGN_VMD_DMA_OPS(source, dest, mapping_error); + ASSIGN_VMD_DMA_OPS(source, dest, dma_supported); +#ifdef ARCH_HAS_DMA_GET_REQUIRED_MASK + ASSIGN_VMD_DMA_OPS(source, dest, get_required_mask); +#endif + add_dma_domain(domain); +} +#undef ASSIGN_VMD_DMA_OPS +#else +static void vmd_teardown_dma_ops(struct vmd_dev *vmd) {} +static void vmd_setup_dma_ops(struct vmd_dev *vmd) {} +#endif + +static char __iomem *vmd_cfg_addr(struct vmd_dev *vmd, struct pci_bus *bus, + unsigned int devfn, int reg, int len) +{ + char __iomem *addr = vmd->cfgbar + + (bus->number << 20) + (devfn << 12) + reg; + + if ((addr - vmd->cfgbar) + len >= + resource_size(&vmd->dev->resource[VMD_CFGBAR])) + return NULL; + + return addr; +} + +/* + * 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); + char __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); + char __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, +}; + +/* + * VMD domains start at 0x1000 to not clash with ACPI _SEG domains. + */ +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_enable_domain(struct vmd_dev *vmd) +{ + struct pci_sysdata *sd = &vmd->sysdata; + struct resource *res; + u32 upper_bits; + unsigned long flags; + LIST_HEAD(resources); + + res = &vmd->dev->resource[VMD_CFGBAR]; + vmd->resources[0] = (struct resource) { + .name = "VMD CFGBAR", + .start = res->start, + .end = (resource_size(res) >> 20) - 1, + .flags = IORESOURCE_BUS | IORESOURCE_PCI_FIXED, + }; + + 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, + }; + + 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 + 0x2000, + .end = res->end, + .flags = flags, + }; + + sd->domain = vmd_find_free_domain(); + if (sd->domain < 0) + return sd->domain; + + sd->node = pcibus_to_node(vmd->dev->bus); + + vmd->irq_domain = pci_msi_create_irq_domain(NULL, &vmd_msi_domain_info, + NULL); + if (!vmd->irq_domain) + return -ENODEV; + + pci_add_resource(&resources, &vmd->resources[0]); + pci_add_resource(&resources, &vmd->resources[1]); + pci_add_resource(&resources, &vmd->resources[2]); + vmd->bus = pci_create_root_bus(&vmd->dev->dev, 0, &vmd_ops, sd, + &resources); + if (!vmd->bus) { + pci_free_resource_list(&resources); + irq_domain_remove(vmd->irq_domain); + return -ENODEV; + } + + vmd_setup_dma_ops(vmd); + dev_set_msi_domain(&vmd->bus->dev, vmd->irq_domain); + pci_rescan_bus(vmd->bus); + + WARN(sysfs_create_link(&vmd->dev->dev.kobj, &vmd->bus->dev.kobj, + "domain"), "Can't create symlink to domain\n"); + return 0; +} + +static irqreturn_t vmd_irq(int irq, void *data) +{ + struct vmd_irq_list *irqs = data; + struct vmd_irq *vmdirq; + + rcu_read_lock(); + list_for_each_entry_rcu(vmdirq, &irqs->irq_list, node) + generic_handle_irq(vmdirq->virq); + rcu_read_unlock(); + + return IRQ_HANDLED; +} + +static int vmd_probe(struct pci_dev *dev, const struct pci_device_id *id) +{ + struct vmd_dev *vmd; + int i, 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; + err = pcim_enable_device(dev); + if (err < 0) + return err; + + vmd->cfgbar = pcim_iomap(dev, VMD_CFGBAR, 0); + if (!vmd->cfgbar) + return -ENOMEM; + + 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))) + return -ENODEV; + + vmd->msix_count = pci_msix_vec_count(dev); + if (vmd->msix_count < 0) + return -ENODEV; + + vmd->irqs = devm_kcalloc(&dev->dev, vmd->msix_count, sizeof(*vmd->irqs), + GFP_KERNEL); + if (!vmd->irqs) + return -ENOMEM; + + vmd->msix_entries = devm_kcalloc(&dev->dev, vmd->msix_count, + sizeof(*vmd->msix_entries), + GFP_KERNEL); + if (!vmd->msix_entries) + return -ENOMEM; + for (i = 0; i < vmd->msix_count; i++) + vmd->msix_entries[i].entry = i; + + vmd->msix_count = pci_enable_msix_range(vmd->dev, vmd->msix_entries, 1, + vmd->msix_count); + if (vmd->msix_count < 0) + return vmd->msix_count; + + for (i = 0; i < vmd->msix_count; i++) { + INIT_LIST_HEAD(&vmd->irqs[i].irq_list); + vmd->irqs[i].vmd_vector = vmd->msix_entries[i].vector; + vmd->irqs[i].index = i; + + err = devm_request_irq(&dev->dev, vmd->irqs[i].vmd_vector, + vmd_irq, 0, "vmd", &vmd->irqs[i]); + if (err) + return err; + } + + spin_lock_init(&vmd->cfg_lock); + pci_set_drvdata(dev, vmd); + err = vmd_enable_domain(vmd); + if (err) + return err; + + dev_info(&vmd->dev->dev, "Bound to PCI domain %04x\n", + vmd->sysdata.domain); + return 0; +} + +static void vmd_remove(struct pci_dev *dev) +{ + struct vmd_dev *vmd = pci_get_drvdata(dev); + + pci_set_drvdata(dev, NULL); + sysfs_remove_link(&vmd->dev->dev.kobj, "domain"); + pci_stop_root_bus(vmd->bus); + pci_remove_root_bus(vmd->bus); + vmd_teardown_dma_ops(vmd); + irq_domain_remove(vmd->irq_domain); +} + +#ifdef CONFIG_PM +static int vmd_suspend(struct device *dev) +{ + struct pci_dev *pdev = to_pci_dev(dev); + + pci_save_state(pdev); + return 0; +} + +static int vmd_resume(struct device *dev) +{ + struct pci_dev *pdev = to_pci_dev(dev); + + pci_restore_state(pdev); + 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_DEVICE(PCI_VENDOR_ID_INTEL, 0x201d),}, + {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, + .driver = { + .pm = &vmd_dev_pm_ops, + }, +}; +module_pci_driver(vmd_drv); + +MODULE_AUTHOR("Intel Corporation"); +MODULE_LICENSE("GPL v2"); +MODULE_VERSION("0.6"); |