diff options
Diffstat (limited to 'kernel/linux/igb_uio/igb_uio.c')
-rw-r--r-- | kernel/linux/igb_uio/igb_uio.c | 669 |
1 files changed, 669 insertions, 0 deletions
diff --git a/kernel/linux/igb_uio/igb_uio.c b/kernel/linux/igb_uio/igb_uio.c new file mode 100644 index 00000000..3398eacd --- /dev/null +++ b/kernel/linux/igb_uio/igb_uio.c @@ -0,0 +1,669 @@ +// SPDX-License-Identifier: GPL-2.0 +/*- + * Copyright(c) 2010-2017 Intel Corporation. All rights reserved. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/device.h> +#include <linux/module.h> +#include <linux/pci.h> +#include <linux/uio_driver.h> +#include <linux/io.h> +#include <linux/irq.h> +#include <linux/msi.h> +#include <linux/version.h> +#include <linux/slab.h> + +#include <rte_pci_dev_features.h> + +#include "compat.h" + +/** + * A structure describing the private information for a uio device. + */ +struct rte_uio_pci_dev { + struct uio_info info; + struct pci_dev *pdev; + enum rte_intr_mode mode; + struct mutex lock; + int refcnt; +}; + +static int wc_activate; +static char *intr_mode; +static enum rte_intr_mode igbuio_intr_mode_preferred = RTE_INTR_MODE_MSIX; +/* sriov sysfs */ +static ssize_t +show_max_vfs(struct device *dev, struct device_attribute *attr, + char *buf) +{ + return snprintf(buf, 10, "%u\n", dev_num_vf(dev)); +} + +static ssize_t +store_max_vfs(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + int err = 0; + unsigned long max_vfs; + struct pci_dev *pdev = to_pci_dev(dev); + + if (0 != kstrtoul(buf, 0, &max_vfs)) + return -EINVAL; + + if (0 == max_vfs) + pci_disable_sriov(pdev); + else if (0 == pci_num_vf(pdev)) + err = pci_enable_sriov(pdev, max_vfs); + else /* do nothing if change max_vfs number */ + err = -EINVAL; + + return err ? err : count; +} + +static DEVICE_ATTR(max_vfs, S_IRUGO | S_IWUSR, show_max_vfs, store_max_vfs); + +static struct attribute *dev_attrs[] = { + &dev_attr_max_vfs.attr, + NULL, +}; + +static const struct attribute_group dev_attr_grp = { + .attrs = dev_attrs, +}; + +#ifndef HAVE_PCI_MSI_MASK_IRQ +/* + * It masks the msix on/off of generating MSI-X messages. + */ +static void +igbuio_msix_mask_irq(struct msi_desc *desc, s32 state) +{ + u32 mask_bits = desc->masked; + unsigned int offset = desc->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE + + PCI_MSIX_ENTRY_VECTOR_CTRL; + + if (state != 0) + mask_bits &= ~PCI_MSIX_ENTRY_CTRL_MASKBIT; + else + mask_bits |= PCI_MSIX_ENTRY_CTRL_MASKBIT; + + if (mask_bits != desc->masked) { + writel(mask_bits, desc->mask_base + offset); + readl(desc->mask_base); + desc->masked = mask_bits; + } +} + +/* + * It masks the msi on/off of generating MSI messages. + */ +static void +igbuio_msi_mask_irq(struct pci_dev *pdev, struct msi_desc *desc, int32_t state) +{ + u32 mask_bits = desc->masked; + u32 offset = desc->irq - pdev->irq; + u32 mask = 1 << offset; + + if (!desc->msi_attrib.maskbit) + return; + + if (state != 0) + mask_bits &= ~mask; + else + mask_bits |= mask; + + if (mask_bits != desc->masked) { + pci_write_config_dword(pdev, desc->mask_pos, mask_bits); + desc->masked = mask_bits; + } +} + +static void +igbuio_mask_irq(struct pci_dev *pdev, enum rte_intr_mode mode, s32 irq_state) +{ + struct msi_desc *desc; + struct list_head *msi_list; + +#ifdef HAVE_MSI_LIST_IN_GENERIC_DEVICE + msi_list = &pdev->dev.msi_list; +#else + msi_list = &pdev->msi_list; +#endif + + if (mode == RTE_INTR_MODE_MSIX) { + list_for_each_entry(desc, msi_list, list) + igbuio_msix_mask_irq(desc, irq_state); + } else if (mode == RTE_INTR_MODE_MSI) { + list_for_each_entry(desc, msi_list, list) + igbuio_msi_mask_irq(pdev, desc, irq_state); + } +} +#endif + +/** + * This is the irqcontrol callback to be registered to uio_info. + * It can be used to disable/enable interrupt from user space processes. + * + * @param info + * pointer to uio_info. + * @param irq_state + * state value. 1 to enable interrupt, 0 to disable interrupt. + * + * @return + * - On success, 0. + * - On failure, a negative value. + */ +static int +igbuio_pci_irqcontrol(struct uio_info *info, s32 irq_state) +{ + struct rte_uio_pci_dev *udev = info->priv; + struct pci_dev *pdev = udev->pdev; + +#ifdef HAVE_PCI_MSI_MASK_IRQ + struct irq_data *irq = irq_get_irq_data(udev->info.irq); +#endif + + pci_cfg_access_lock(pdev); + + if (udev->mode == RTE_INTR_MODE_MSIX || udev->mode == RTE_INTR_MODE_MSI) { +#ifdef HAVE_PCI_MSI_MASK_IRQ + if (irq_state == 1) + pci_msi_unmask_irq(irq); + else + pci_msi_mask_irq(irq); +#else + igbuio_mask_irq(pdev, udev->mode, irq_state); +#endif + } + + if (udev->mode == RTE_INTR_MODE_LEGACY) + pci_intx(pdev, !!irq_state); + + pci_cfg_access_unlock(pdev); + + return 0; +} + +/** + * This is interrupt handler which will check if the interrupt is for the right device. + * If yes, disable it here and will be enable later. + */ +static irqreturn_t +igbuio_pci_irqhandler(int irq, void *dev_id) +{ + struct rte_uio_pci_dev *udev = (struct rte_uio_pci_dev *)dev_id; + struct uio_info *info = &udev->info; + + /* Legacy mode need to mask in hardware */ + if (udev->mode == RTE_INTR_MODE_LEGACY && + !pci_check_and_mask_intx(udev->pdev)) + return IRQ_NONE; + + uio_event_notify(info); + + /* Message signal mode, no share IRQ and automasked */ + return IRQ_HANDLED; +} + +static int +igbuio_pci_enable_interrupts(struct rte_uio_pci_dev *udev) +{ + int err = 0; +#ifndef HAVE_ALLOC_IRQ_VECTORS + struct msix_entry msix_entry; +#endif + + switch (igbuio_intr_mode_preferred) { + case RTE_INTR_MODE_MSIX: + /* Only 1 msi-x vector needed */ +#ifndef HAVE_ALLOC_IRQ_VECTORS + msix_entry.entry = 0; + if (pci_enable_msix(udev->pdev, &msix_entry, 1) == 0) { + dev_dbg(&udev->pdev->dev, "using MSI-X"); + udev->info.irq_flags = IRQF_NO_THREAD; + udev->info.irq = msix_entry.vector; + udev->mode = RTE_INTR_MODE_MSIX; + break; + } +#else + if (pci_alloc_irq_vectors(udev->pdev, 1, 1, PCI_IRQ_MSIX) == 1) { + dev_dbg(&udev->pdev->dev, "using MSI-X"); + udev->info.irq_flags = IRQF_NO_THREAD; + udev->info.irq = pci_irq_vector(udev->pdev, 0); + udev->mode = RTE_INTR_MODE_MSIX; + break; + } +#endif + + /* fall back to MSI */ + case RTE_INTR_MODE_MSI: +#ifndef HAVE_ALLOC_IRQ_VECTORS + if (pci_enable_msi(udev->pdev) == 0) { + dev_dbg(&udev->pdev->dev, "using MSI"); + udev->info.irq_flags = IRQF_NO_THREAD; + udev->info.irq = udev->pdev->irq; + udev->mode = RTE_INTR_MODE_MSI; + break; + } +#else + if (pci_alloc_irq_vectors(udev->pdev, 1, 1, PCI_IRQ_MSI) == 1) { + dev_dbg(&udev->pdev->dev, "using MSI"); + udev->info.irq_flags = IRQF_NO_THREAD; + udev->info.irq = pci_irq_vector(udev->pdev, 0); + udev->mode = RTE_INTR_MODE_MSI; + break; + } +#endif + /* fall back to INTX */ + case RTE_INTR_MODE_LEGACY: + if (pci_intx_mask_supported(udev->pdev)) { + dev_dbg(&udev->pdev->dev, "using INTX"); + udev->info.irq_flags = IRQF_SHARED | IRQF_NO_THREAD; + udev->info.irq = udev->pdev->irq; + udev->mode = RTE_INTR_MODE_LEGACY; + break; + } + dev_notice(&udev->pdev->dev, "PCI INTX mask not supported\n"); + /* fall back to no IRQ */ + case RTE_INTR_MODE_NONE: + udev->mode = RTE_INTR_MODE_NONE; + udev->info.irq = UIO_IRQ_NONE; + break; + + default: + dev_err(&udev->pdev->dev, "invalid IRQ mode %u", + igbuio_intr_mode_preferred); + udev->info.irq = UIO_IRQ_NONE; + err = -EINVAL; + } + + if (udev->info.irq != UIO_IRQ_NONE) + err = request_irq(udev->info.irq, igbuio_pci_irqhandler, + udev->info.irq_flags, udev->info.name, + udev); + dev_info(&udev->pdev->dev, "uio device registered with irq %ld\n", + udev->info.irq); + + return err; +} + +static void +igbuio_pci_disable_interrupts(struct rte_uio_pci_dev *udev) +{ + if (udev->info.irq) { + free_irq(udev->info.irq, udev); + udev->info.irq = 0; + } + +#ifndef HAVE_ALLOC_IRQ_VECTORS + if (udev->mode == RTE_INTR_MODE_MSIX) + pci_disable_msix(udev->pdev); + if (udev->mode == RTE_INTR_MODE_MSI) + pci_disable_msi(udev->pdev); +#else + if (udev->mode == RTE_INTR_MODE_MSIX || + udev->mode == RTE_INTR_MODE_MSI) + pci_free_irq_vectors(udev->pdev); +#endif +} + + +/** + * This gets called while opening uio device file. + */ +static int +igbuio_pci_open(struct uio_info *info, struct inode *inode) +{ + struct rte_uio_pci_dev *udev = info->priv; + struct pci_dev *dev = udev->pdev; + int err; + + mutex_lock(&udev->lock); + if (++udev->refcnt > 1) { + mutex_unlock(&udev->lock); + return 0; + } + + /* set bus master, which was cleared by the reset function */ + pci_set_master(dev); + + /* enable interrupts */ + err = igbuio_pci_enable_interrupts(udev); + mutex_unlock(&udev->lock); + if (err) { + dev_err(&dev->dev, "Enable interrupt fails\n"); + return err; + } + return 0; +} + +static int +igbuio_pci_release(struct uio_info *info, struct inode *inode) +{ + struct rte_uio_pci_dev *udev = info->priv; + struct pci_dev *dev = udev->pdev; + + mutex_lock(&udev->lock); + if (--udev->refcnt > 0) { + mutex_unlock(&udev->lock); + return 0; + } + + /* disable interrupts */ + igbuio_pci_disable_interrupts(udev); + + /* stop the device from further DMA */ + pci_clear_master(dev); + + mutex_unlock(&udev->lock); + return 0; +} + +/* Remap pci resources described by bar #pci_bar in uio resource n. */ +static int +igbuio_pci_setup_iomem(struct pci_dev *dev, struct uio_info *info, + int n, int pci_bar, const char *name) +{ + unsigned long addr, len; + void *internal_addr; + + if (n >= ARRAY_SIZE(info->mem)) + return -EINVAL; + + addr = pci_resource_start(dev, pci_bar); + len = pci_resource_len(dev, pci_bar); + if (addr == 0 || len == 0) + return -1; + if (wc_activate == 0) { + internal_addr = ioremap(addr, len); + if (internal_addr == NULL) + return -1; + } else { + internal_addr = NULL; + } + info->mem[n].name = name; + info->mem[n].addr = addr; + info->mem[n].internal_addr = internal_addr; + info->mem[n].size = len; + info->mem[n].memtype = UIO_MEM_PHYS; + return 0; +} + +/* Get pci port io resources described by bar #pci_bar in uio resource n. */ +static int +igbuio_pci_setup_ioport(struct pci_dev *dev, struct uio_info *info, + int n, int pci_bar, const char *name) +{ + unsigned long addr, len; + + if (n >= ARRAY_SIZE(info->port)) + return -EINVAL; + + addr = pci_resource_start(dev, pci_bar); + len = pci_resource_len(dev, pci_bar); + if (addr == 0 || len == 0) + return -EINVAL; + + info->port[n].name = name; + info->port[n].start = addr; + info->port[n].size = len; + info->port[n].porttype = UIO_PORT_X86; + + return 0; +} + +/* Unmap previously ioremap'd resources */ +static void +igbuio_pci_release_iomem(struct uio_info *info) +{ + int i; + + for (i = 0; i < MAX_UIO_MAPS; i++) { + if (info->mem[i].internal_addr) + iounmap(info->mem[i].internal_addr); + } +} + +static int +igbuio_setup_bars(struct pci_dev *dev, struct uio_info *info) +{ + int i, iom, iop, ret; + unsigned long flags; + static const char *bar_names[PCI_STD_RESOURCE_END + 1] = { + "BAR0", + "BAR1", + "BAR2", + "BAR3", + "BAR4", + "BAR5", + }; + + iom = 0; + iop = 0; + + for (i = 0; i < ARRAY_SIZE(bar_names); i++) { + if (pci_resource_len(dev, i) != 0 && + pci_resource_start(dev, i) != 0) { + flags = pci_resource_flags(dev, i); + if (flags & IORESOURCE_MEM) { + ret = igbuio_pci_setup_iomem(dev, info, iom, + i, bar_names[i]); + if (ret != 0) + return ret; + iom++; + } else if (flags & IORESOURCE_IO) { + ret = igbuio_pci_setup_ioport(dev, info, iop, + i, bar_names[i]); + if (ret != 0) + return ret; + iop++; + } + } + } + + return (iom != 0 || iop != 0) ? ret : -ENOENT; +} + +#if LINUX_VERSION_CODE < KERNEL_VERSION(3, 8, 0) +static int __devinit +#else +static int +#endif +igbuio_pci_probe(struct pci_dev *dev, const struct pci_device_id *id) +{ + struct rte_uio_pci_dev *udev; + dma_addr_t map_dma_addr; + void *map_addr; + int err; + +#ifdef HAVE_PCI_IS_BRIDGE_API + if (pci_is_bridge(dev)) { + dev_warn(&dev->dev, "Ignoring PCI bridge device\n"); + return -ENODEV; + } +#endif + + udev = kzalloc(sizeof(struct rte_uio_pci_dev), GFP_KERNEL); + if (!udev) + return -ENOMEM; + + mutex_init(&udev->lock); + /* + * enable device: ask low-level code to enable I/O and + * memory + */ + err = pci_enable_device(dev); + if (err != 0) { + dev_err(&dev->dev, "Cannot enable PCI device\n"); + goto fail_free; + } + + /* enable bus mastering on the device */ + pci_set_master(dev); + + /* remap IO memory */ + err = igbuio_setup_bars(dev, &udev->info); + if (err != 0) + goto fail_release_iomem; + + /* set 64-bit DMA mask */ + err = pci_set_dma_mask(dev, DMA_BIT_MASK(64)); + if (err != 0) { + dev_err(&dev->dev, "Cannot set DMA mask\n"); + goto fail_release_iomem; + } + + err = pci_set_consistent_dma_mask(dev, DMA_BIT_MASK(64)); + if (err != 0) { + dev_err(&dev->dev, "Cannot set consistent DMA mask\n"); + goto fail_release_iomem; + } + + /* fill uio infos */ + udev->info.name = "igb_uio"; + udev->info.version = "0.1"; + udev->info.irqcontrol = igbuio_pci_irqcontrol; + udev->info.open = igbuio_pci_open; + udev->info.release = igbuio_pci_release; + udev->info.priv = udev; + udev->pdev = dev; + + err = sysfs_create_group(&dev->dev.kobj, &dev_attr_grp); + if (err != 0) + goto fail_release_iomem; + + /* register uio driver */ + err = uio_register_device(&dev->dev, &udev->info); + if (err != 0) + goto fail_remove_group; + + pci_set_drvdata(dev, udev); + + /* + * Doing a harmless dma mapping for attaching the device to + * the iommu identity mapping if kernel boots with iommu=pt. + * Note this is not a problem if no IOMMU at all. + */ + map_addr = dma_alloc_coherent(&dev->dev, 1024, &map_dma_addr, + GFP_KERNEL); + if (map_addr) + memset(map_addr, 0, 1024); + + if (!map_addr) + dev_info(&dev->dev, "dma mapping failed\n"); + else { + dev_info(&dev->dev, "mapping 1K dma=%#llx host=%p\n", + (unsigned long long)map_dma_addr, map_addr); + + dma_free_coherent(&dev->dev, 1024, map_addr, map_dma_addr); + dev_info(&dev->dev, "unmapping 1K dma=%#llx host=%p\n", + (unsigned long long)map_dma_addr, map_addr); + } + + return 0; + +fail_remove_group: + sysfs_remove_group(&dev->dev.kobj, &dev_attr_grp); +fail_release_iomem: + igbuio_pci_release_iomem(&udev->info); + pci_disable_device(dev); +fail_free: + kfree(udev); + + return err; +} + +static void +igbuio_pci_remove(struct pci_dev *dev) +{ + struct rte_uio_pci_dev *udev = pci_get_drvdata(dev); + + mutex_destroy(&udev->lock); + sysfs_remove_group(&dev->dev.kobj, &dev_attr_grp); + uio_unregister_device(&udev->info); + igbuio_pci_release_iomem(&udev->info); + pci_disable_device(dev); + pci_set_drvdata(dev, NULL); + kfree(udev); +} + +static int +igbuio_config_intr_mode(char *intr_str) +{ + if (!intr_str) { + pr_info("Use MSIX interrupt by default\n"); + return 0; + } + + if (!strcmp(intr_str, RTE_INTR_MODE_MSIX_NAME)) { + igbuio_intr_mode_preferred = RTE_INTR_MODE_MSIX; + pr_info("Use MSIX interrupt\n"); + } else if (!strcmp(intr_str, RTE_INTR_MODE_MSI_NAME)) { + igbuio_intr_mode_preferred = RTE_INTR_MODE_MSI; + pr_info("Use MSI interrupt\n"); + } else if (!strcmp(intr_str, RTE_INTR_MODE_LEGACY_NAME)) { + igbuio_intr_mode_preferred = RTE_INTR_MODE_LEGACY; + pr_info("Use legacy interrupt\n"); + } else { + pr_info("Error: bad parameter - %s\n", intr_str); + return -EINVAL; + } + + return 0; +} + +static struct pci_driver igbuio_pci_driver = { + .name = "igb_uio", + .id_table = NULL, + .probe = igbuio_pci_probe, + .remove = igbuio_pci_remove, +}; + +static int __init +igbuio_pci_init_module(void) +{ + int ret; + + if (igbuio_kernel_is_locked_down()) { + pr_err("Not able to use module, kernel lock down is enabled\n"); + return -EINVAL; + } + + if (wc_activate != 0) + pr_info("wc_activate is set\n"); + + ret = igbuio_config_intr_mode(intr_mode); + if (ret < 0) + return ret; + + return pci_register_driver(&igbuio_pci_driver); +} + +static void __exit +igbuio_pci_exit_module(void) +{ + pci_unregister_driver(&igbuio_pci_driver); +} + +module_init(igbuio_pci_init_module); +module_exit(igbuio_pci_exit_module); + +module_param(intr_mode, charp, S_IRUGO); +MODULE_PARM_DESC(intr_mode, +"igb_uio interrupt mode (default=msix):\n" +" " RTE_INTR_MODE_MSIX_NAME " Use MSIX interrupt\n" +" " RTE_INTR_MODE_MSI_NAME " Use MSI interrupt\n" +" " RTE_INTR_MODE_LEGACY_NAME " Use Legacy interrupt\n" +"\n"); + +module_param(wc_activate, int, 0); +MODULE_PARM_DESC(wc_activate, +"Activate support for write combining (WC) (default=0)\n" +" 0 - disable\n" +" other - enable\n"); + +MODULE_DESCRIPTION("UIO driver for Intel IGB PCI cards"); +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Intel Corporation"); |