diff options
Diffstat (limited to 'hw/pci/msix.c')
| -rw-r--r-- | hw/pci/msix.c | 562 |
1 files changed, 562 insertions, 0 deletions
diff --git a/hw/pci/msix.c b/hw/pci/msix.c new file mode 100644 index 0000000000..136ef09373 --- /dev/null +++ b/hw/pci/msix.c @@ -0,0 +1,562 @@ +/* + * MSI-X device support + * + * This module includes support for MSI-X in pci devices. + * + * Author: Michael S. Tsirkin <mst@redhat.com> + * + * Copyright (c) 2009, Red Hat Inc, Michael S. Tsirkin (mst@redhat.com) + * + * This work is licensed under the terms of the GNU GPL, version 2. See + * the COPYING file in the top-level directory. + * + * Contributions after 2012-01-13 are licensed under the terms of the + * GNU GPL, version 2 or (at your option) any later version. + */ + +#include "hw.h" +#include "msi.h" +#include "msix.h" +#include "pci.h" +#include "range.h" + +#define MSIX_CAP_LENGTH 12 + +/* MSI enable bit and maskall bit are in byte 1 in FLAGS register */ +#define MSIX_CONTROL_OFFSET (PCI_MSIX_FLAGS + 1) +#define MSIX_ENABLE_MASK (PCI_MSIX_FLAGS_ENABLE >> 8) +#define MSIX_MASKALL_MASK (PCI_MSIX_FLAGS_MASKALL >> 8) + +static MSIMessage msix_get_message(PCIDevice *dev, unsigned vector) +{ + uint8_t *table_entry = dev->msix_table + vector * PCI_MSIX_ENTRY_SIZE; + MSIMessage msg; + + msg.address = pci_get_quad(table_entry + PCI_MSIX_ENTRY_LOWER_ADDR); + msg.data = pci_get_long(table_entry + PCI_MSIX_ENTRY_DATA); + return msg; +} + +/* + * Special API for POWER to configure the vectors through + * a side channel. Should never be used by devices. + */ +void msix_set_message(PCIDevice *dev, int vector, struct MSIMessage msg) +{ + uint8_t *table_entry = dev->msix_table + vector * PCI_MSIX_ENTRY_SIZE; + + pci_set_quad(table_entry + PCI_MSIX_ENTRY_LOWER_ADDR, msg.address); + pci_set_long(table_entry + PCI_MSIX_ENTRY_DATA, msg.data); + table_entry[PCI_MSIX_ENTRY_VECTOR_CTRL] &= ~PCI_MSIX_ENTRY_CTRL_MASKBIT; +} + +static uint8_t msix_pending_mask(int vector) +{ + return 1 << (vector % 8); +} + +static uint8_t *msix_pending_byte(PCIDevice *dev, int vector) +{ + return dev->msix_pba + vector / 8; +} + +static int msix_is_pending(PCIDevice *dev, int vector) +{ + return *msix_pending_byte(dev, vector) & msix_pending_mask(vector); +} + +static void msix_set_pending(PCIDevice *dev, int vector) +{ + *msix_pending_byte(dev, vector) |= msix_pending_mask(vector); +} + +static void msix_clr_pending(PCIDevice *dev, int vector) +{ + *msix_pending_byte(dev, vector) &= ~msix_pending_mask(vector); +} + +static bool msix_vector_masked(PCIDevice *dev, int vector, bool fmask) +{ + unsigned offset = vector * PCI_MSIX_ENTRY_SIZE + PCI_MSIX_ENTRY_VECTOR_CTRL; + return fmask || dev->msix_table[offset] & PCI_MSIX_ENTRY_CTRL_MASKBIT; +} + +static bool msix_is_masked(PCIDevice *dev, int vector) +{ + return msix_vector_masked(dev, vector, dev->msix_function_masked); +} + +static void msix_fire_vector_notifier(PCIDevice *dev, + unsigned int vector, bool is_masked) +{ + MSIMessage msg; + int ret; + + if (!dev->msix_vector_use_notifier) { + return; + } + if (is_masked) { + dev->msix_vector_release_notifier(dev, vector); + } else { + msg = msix_get_message(dev, vector); + ret = dev->msix_vector_use_notifier(dev, vector, msg); + assert(ret >= 0); + } +} + +static void msix_handle_mask_update(PCIDevice *dev, int vector, bool was_masked) +{ + bool is_masked = msix_is_masked(dev, vector); + + if (is_masked == was_masked) { + return; + } + + msix_fire_vector_notifier(dev, vector, is_masked); + + if (!is_masked && msix_is_pending(dev, vector)) { + msix_clr_pending(dev, vector); + msix_notify(dev, vector); + } +} + +static void msix_update_function_masked(PCIDevice *dev) +{ + dev->msix_function_masked = !msix_enabled(dev) || + (dev->config[dev->msix_cap + MSIX_CONTROL_OFFSET] & MSIX_MASKALL_MASK); +} + +/* Handle MSI-X capability config write. */ +void msix_write_config(PCIDevice *dev, uint32_t addr, + uint32_t val, int len) +{ + unsigned enable_pos = dev->msix_cap + MSIX_CONTROL_OFFSET; + int vector; + bool was_masked; + + if (!msix_present(dev) || !range_covers_byte(addr, len, enable_pos)) { + return; + } + + was_masked = dev->msix_function_masked; + msix_update_function_masked(dev); + + if (!msix_enabled(dev)) { + return; + } + + pci_device_deassert_intx(dev); + + if (dev->msix_function_masked == was_masked) { + return; + } + + for (vector = 0; vector < dev->msix_entries_nr; ++vector) { + msix_handle_mask_update(dev, vector, + msix_vector_masked(dev, vector, was_masked)); + } +} + +static uint64_t msix_table_mmio_read(void *opaque, hwaddr addr, + unsigned size) +{ + PCIDevice *dev = opaque; + + return pci_get_long(dev->msix_table + addr); +} + +static void msix_table_mmio_write(void *opaque, hwaddr addr, + uint64_t val, unsigned size) +{ + PCIDevice *dev = opaque; + int vector = addr / PCI_MSIX_ENTRY_SIZE; + bool was_masked; + + was_masked = msix_is_masked(dev, vector); + pci_set_long(dev->msix_table + addr, val); + msix_handle_mask_update(dev, vector, was_masked); +} + +static const MemoryRegionOps msix_table_mmio_ops = { + .read = msix_table_mmio_read, + .write = msix_table_mmio_write, + /* TODO: MSIX should be LITTLE_ENDIAN. */ + .endianness = DEVICE_NATIVE_ENDIAN, + .valid = { + .min_access_size = 4, + .max_access_size = 4, + }, +}; + +static uint64_t msix_pba_mmio_read(void *opaque, hwaddr addr, + unsigned size) +{ + PCIDevice *dev = opaque; + + return pci_get_long(dev->msix_pba + addr); +} + +static const MemoryRegionOps msix_pba_mmio_ops = { + .read = msix_pba_mmio_read, + /* TODO: MSIX should be LITTLE_ENDIAN. */ + .endianness = DEVICE_NATIVE_ENDIAN, + .valid = { + .min_access_size = 4, + .max_access_size = 4, + }, +}; + +static void msix_mask_all(struct PCIDevice *dev, unsigned nentries) +{ + int vector; + + for (vector = 0; vector < nentries; ++vector) { + unsigned offset = + vector * PCI_MSIX_ENTRY_SIZE + PCI_MSIX_ENTRY_VECTOR_CTRL; + bool was_masked = msix_is_masked(dev, vector); + + dev->msix_table[offset] |= PCI_MSIX_ENTRY_CTRL_MASKBIT; + msix_handle_mask_update(dev, vector, was_masked); + } +} + +/* Initialize the MSI-X structures */ +int msix_init(struct PCIDevice *dev, unsigned short nentries, + MemoryRegion *table_bar, uint8_t table_bar_nr, + unsigned table_offset, MemoryRegion *pba_bar, + uint8_t pba_bar_nr, unsigned pba_offset, uint8_t cap_pos) +{ + int cap; + unsigned table_size, pba_size; + uint8_t *config; + + /* Nothing to do if MSI is not supported by interrupt controller */ + if (!msi_supported) { + return -ENOTSUP; + } + + if (nentries < 1 || nentries > PCI_MSIX_FLAGS_QSIZE + 1) { + return -EINVAL; + } + + table_size = nentries * PCI_MSIX_ENTRY_SIZE; + pba_size = QEMU_ALIGN_UP(nentries, 64) / 8; + + /* Sanity test: table & pba don't overlap, fit within BARs, min aligned */ + if ((table_bar_nr == pba_bar_nr && + ranges_overlap(table_offset, table_size, pba_offset, pba_size)) || + table_offset + table_size > memory_region_size(table_bar) || + pba_offset + pba_size > memory_region_size(pba_bar) || + (table_offset | pba_offset) & PCI_MSIX_FLAGS_BIRMASK) { + return -EINVAL; + } + + cap = pci_add_capability(dev, PCI_CAP_ID_MSIX, cap_pos, MSIX_CAP_LENGTH); + if (cap < 0) { + return cap; + } + + dev->msix_cap = cap; + dev->cap_present |= QEMU_PCI_CAP_MSIX; + config = dev->config + cap; + + pci_set_word(config + PCI_MSIX_FLAGS, nentries - 1); + dev->msix_entries_nr = nentries; + dev->msix_function_masked = true; + + pci_set_long(config + PCI_MSIX_TABLE, table_offset | table_bar_nr); + pci_set_long(config + PCI_MSIX_PBA, pba_offset | pba_bar_nr); + + /* Make flags bit writable. */ + dev->wmask[cap + MSIX_CONTROL_OFFSET] |= MSIX_ENABLE_MASK | + MSIX_MASKALL_MASK; + + dev->msix_table = g_malloc0(table_size); + dev->msix_pba = g_malloc0(pba_size); + dev->msix_entry_used = g_malloc0(nentries * sizeof *dev->msix_entry_used); + + msix_mask_all(dev, nentries); + + memory_region_init_io(&dev->msix_table_mmio, &msix_table_mmio_ops, dev, + "msix-table", table_size); + memory_region_add_subregion(table_bar, table_offset, &dev->msix_table_mmio); + memory_region_init_io(&dev->msix_pba_mmio, &msix_pba_mmio_ops, dev, + "msix-pba", pba_size); + memory_region_add_subregion(pba_bar, pba_offset, &dev->msix_pba_mmio); + + return 0; +} + +int msix_init_exclusive_bar(PCIDevice *dev, unsigned short nentries, + uint8_t bar_nr) +{ + int ret; + char *name; + + /* + * Migration compatibility dictates that this remains a 4k + * BAR with the vector table in the lower half and PBA in + * the upper half. Do not use these elsewhere! + */ +#define MSIX_EXCLUSIVE_BAR_SIZE 4096 +#define MSIX_EXCLUSIVE_BAR_TABLE_OFFSET 0 +#define MSIX_EXCLUSIVE_BAR_PBA_OFFSET (MSIX_EXCLUSIVE_BAR_SIZE / 2) +#define MSIX_EXCLUSIVE_CAP_OFFSET 0 + + if (nentries * PCI_MSIX_ENTRY_SIZE > MSIX_EXCLUSIVE_BAR_PBA_OFFSET) { + return -EINVAL; + } + + name = g_strdup_printf("%s-msix", dev->name); + memory_region_init(&dev->msix_exclusive_bar, name, MSIX_EXCLUSIVE_BAR_SIZE); + g_free(name); + + ret = msix_init(dev, nentries, &dev->msix_exclusive_bar, bar_nr, + MSIX_EXCLUSIVE_BAR_TABLE_OFFSET, &dev->msix_exclusive_bar, + bar_nr, MSIX_EXCLUSIVE_BAR_PBA_OFFSET, + MSIX_EXCLUSIVE_CAP_OFFSET); + if (ret) { + memory_region_destroy(&dev->msix_exclusive_bar); + return ret; + } + + pci_register_bar(dev, bar_nr, PCI_BASE_ADDRESS_SPACE_MEMORY, + &dev->msix_exclusive_bar); + + return 0; +} + +static void msix_free_irq_entries(PCIDevice *dev) +{ + int vector; + + for (vector = 0; vector < dev->msix_entries_nr; ++vector) { + dev->msix_entry_used[vector] = 0; + msix_clr_pending(dev, vector); + } +} + +static void msix_clear_all_vectors(PCIDevice *dev) +{ + int vector; + + for (vector = 0; vector < dev->msix_entries_nr; ++vector) { + msix_clr_pending(dev, vector); + } +} + +/* Clean up resources for the device. */ +void msix_uninit(PCIDevice *dev, MemoryRegion *table_bar, MemoryRegion *pba_bar) +{ + if (!msix_present(dev)) { + return; + } + pci_del_capability(dev, PCI_CAP_ID_MSIX, MSIX_CAP_LENGTH); + dev->msix_cap = 0; + msix_free_irq_entries(dev); + dev->msix_entries_nr = 0; + memory_region_del_subregion(pba_bar, &dev->msix_pba_mmio); + memory_region_destroy(&dev->msix_pba_mmio); + g_free(dev->msix_pba); + dev->msix_pba = NULL; + memory_region_del_subregion(table_bar, &dev->msix_table_mmio); + memory_region_destroy(&dev->msix_table_mmio); + g_free(dev->msix_table); + dev->msix_table = NULL; + g_free(dev->msix_entry_used); + dev->msix_entry_used = NULL; + dev->cap_present &= ~QEMU_PCI_CAP_MSIX; +} + +void msix_uninit_exclusive_bar(PCIDevice *dev) +{ + if (msix_present(dev)) { + msix_uninit(dev, &dev->msix_exclusive_bar, &dev->msix_exclusive_bar); + memory_region_destroy(&dev->msix_exclusive_bar); + } +} + +void msix_save(PCIDevice *dev, QEMUFile *f) +{ + unsigned n = dev->msix_entries_nr; + + if (!msix_present(dev)) { + return; + } + + qemu_put_buffer(f, dev->msix_table, n * PCI_MSIX_ENTRY_SIZE); + qemu_put_buffer(f, dev->msix_pba, (n + 7) / 8); +} + +/* Should be called after restoring the config space. */ +void msix_load(PCIDevice *dev, QEMUFile *f) +{ + unsigned n = dev->msix_entries_nr; + unsigned int vector; + + if (!msix_present(dev)) { + return; + } + + msix_clear_all_vectors(dev); + qemu_get_buffer(f, dev->msix_table, n * PCI_MSIX_ENTRY_SIZE); + qemu_get_buffer(f, dev->msix_pba, (n + 7) / 8); + msix_update_function_masked(dev); + + for (vector = 0; vector < n; vector++) { + msix_handle_mask_update(dev, vector, true); + } +} + +/* Does device support MSI-X? */ +int msix_present(PCIDevice *dev) +{ + return dev->cap_present & QEMU_PCI_CAP_MSIX; +} + +/* Is MSI-X enabled? */ +int msix_enabled(PCIDevice *dev) +{ + return (dev->cap_present & QEMU_PCI_CAP_MSIX) && + (dev->config[dev->msix_cap + MSIX_CONTROL_OFFSET] & + MSIX_ENABLE_MASK); +} + +/* Send an MSI-X message */ +void msix_notify(PCIDevice *dev, unsigned vector) +{ + MSIMessage msg; + + if (vector >= dev->msix_entries_nr || !dev->msix_entry_used[vector]) + return; + if (msix_is_masked(dev, vector)) { + msix_set_pending(dev, vector); + return; + } + + msg = msix_get_message(dev, vector); + + stl_le_phys(msg.address, msg.data); +} + +void msix_reset(PCIDevice *dev) +{ + if (!msix_present(dev)) { + return; + } + msix_clear_all_vectors(dev); + dev->config[dev->msix_cap + MSIX_CONTROL_OFFSET] &= + ~dev->wmask[dev->msix_cap + MSIX_CONTROL_OFFSET]; + memset(dev->msix_table, 0, dev->msix_entries_nr * PCI_MSIX_ENTRY_SIZE); + memset(dev->msix_pba, 0, QEMU_ALIGN_UP(dev->msix_entries_nr, 64) / 8); + msix_mask_all(dev, dev->msix_entries_nr); +} + +/* PCI spec suggests that devices make it possible for software to configure + * less vectors than supported by the device, but does not specify a standard + * mechanism for devices to do so. + * + * We support this by asking devices to declare vectors software is going to + * actually use, and checking this on the notification path. Devices that + * don't want to follow the spec suggestion can declare all vectors as used. */ + +/* Mark vector as used. */ +int msix_vector_use(PCIDevice *dev, unsigned vector) +{ + if (vector >= dev->msix_entries_nr) + return -EINVAL; + dev->msix_entry_used[vector]++; + return 0; +} + +/* Mark vector as unused. */ +void msix_vector_unuse(PCIDevice *dev, unsigned vector) +{ + if (vector >= dev->msix_entries_nr || !dev->msix_entry_used[vector]) { + return; + } + if (--dev->msix_entry_used[vector]) { + return; + } + msix_clr_pending(dev, vector); +} + +void msix_unuse_all_vectors(PCIDevice *dev) +{ + if (!msix_present(dev)) { + return; + } + msix_free_irq_entries(dev); +} + +unsigned int msix_nr_vectors_allocated(const PCIDevice *dev) +{ + return dev->msix_entries_nr; +} + +static int msix_set_notifier_for_vector(PCIDevice *dev, unsigned int vector) +{ + MSIMessage msg; + + if (msix_is_masked(dev, vector)) { + return 0; + } + msg = msix_get_message(dev, vector); + return dev->msix_vector_use_notifier(dev, vector, msg); +} + +static void msix_unset_notifier_for_vector(PCIDevice *dev, unsigned int vector) +{ + if (msix_is_masked(dev, vector)) { + return; + } + dev->msix_vector_release_notifier(dev, vector); +} + +int msix_set_vector_notifiers(PCIDevice *dev, + MSIVectorUseNotifier use_notifier, + MSIVectorReleaseNotifier release_notifier) +{ + int vector, ret; + + assert(use_notifier && release_notifier); + + dev->msix_vector_use_notifier = use_notifier; + dev->msix_vector_release_notifier = release_notifier; + + if ((dev->config[dev->msix_cap + MSIX_CONTROL_OFFSET] & + (MSIX_ENABLE_MASK | MSIX_MASKALL_MASK)) == MSIX_ENABLE_MASK) { + for (vector = 0; vector < dev->msix_entries_nr; vector++) { + ret = msix_set_notifier_for_vector(dev, vector); + if (ret < 0) { + goto undo; + } + } + } + return 0; + +undo: + while (--vector >= 0) { + msix_unset_notifier_for_vector(dev, vector); + } + dev->msix_vector_use_notifier = NULL; + dev->msix_vector_release_notifier = NULL; + return ret; +} + +void msix_unset_vector_notifiers(PCIDevice *dev) +{ + int vector; + + assert(dev->msix_vector_use_notifier && + dev->msix_vector_release_notifier); + + if ((dev->config[dev->msix_cap + MSIX_CONTROL_OFFSET] & + (MSIX_ENABLE_MASK | MSIX_MASKALL_MASK)) == MSIX_ENABLE_MASK) { + for (vector = 0; vector < dev->msix_entries_nr; vector++) { + msix_unset_notifier_for_vector(dev, vector); + } + } + dev->msix_vector_use_notifier = NULL; + dev->msix_vector_release_notifier = NULL; +} |