/* * msi.c * * Copyright (c) 2010 Isaku Yamahata * VA Linux Systems Japan K.K. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * This program is distributed in the hope that 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. * You should have received a copy of the GNU General Public License along * with this program; if not, see . */ #include "qemu/osdep.h" #include "hw/pci/msi.h" #include "hw/xen/xen.h" #include "qemu/range.h" #include "qapi/error.h" /* PCI_MSI_ADDRESS_LO */ #define PCI_MSI_ADDRESS_LO_MASK (~0x3) /* If we get rid of cap allocator, we won't need those. */ #define PCI_MSI_32_SIZEOF 0x0a #define PCI_MSI_64_SIZEOF 0x0e #define PCI_MSI_32M_SIZEOF 0x14 #define PCI_MSI_64M_SIZEOF 0x18 #define PCI_MSI_VECTORS_MAX 32 /* * Flag for interrupt controllers to declare broken MSI/MSI-X support. * values: false - broken; true - non-broken. * * Setting this flag to false will remove MSI/MSI-X capability from all devices. * * It is preferable for controllers to set this to true (non-broken) even if * they do not actually support MSI/MSI-X: guests normally probe the controller * type and do not attempt to enable MSI/MSI-X with interrupt controllers not * supporting such, so removing the capability is not required, and * it seems cleaner to have a given device look the same for all boards. * * TODO: some existing controllers violate the above rule. Identify and fix them. */ bool msi_nonbroken; /* If we get rid of cap allocator, we won't need this. */ static inline uint8_t msi_cap_sizeof(uint16_t flags) { switch (flags & (PCI_MSI_FLAGS_MASKBIT | PCI_MSI_FLAGS_64BIT)) { case PCI_MSI_FLAGS_MASKBIT | PCI_MSI_FLAGS_64BIT: return PCI_MSI_64M_SIZEOF; case PCI_MSI_FLAGS_64BIT: return PCI_MSI_64_SIZEOF; case PCI_MSI_FLAGS_MASKBIT: return PCI_MSI_32M_SIZEOF; case 0: return PCI_MSI_32_SIZEOF; default: abort(); break; } return 0; } //#define MSI_DEBUG #ifdef MSI_DEBUG # define MSI_DPRINTF(fmt, ...) \ fprintf(stderr, "%s:%d " fmt, __func__, __LINE__, ## __VA_ARGS__) #else # define MSI_DPRINTF(fmt, ...) do { } while (0) #endif #define MSI_DEV_PRINTF(dev, fmt, ...) \ MSI_DPRINTF("%s:%x " fmt, (dev)->name, (dev)->devfn, ## __VA_ARGS__) static inline unsigned int msi_nr_vectors(uint16_t flags) { return 1U << ((flags & PCI_MSI_FLAGS_QSIZE) >> ctz32(PCI_MSI_FLAGS_QSIZE)); } static inline uint8_t msi_flags_off(const PCIDevice* dev) { return dev->msi_cap + PCI_MSI_FLAGS; } static inline uint8_t msi_address_lo_off(const PCIDevice* dev) { return dev->msi_cap + PCI_MSI_ADDRESS_LO; } static inline uint8_t msi_address_hi_off(const PCIDevice* dev) { return dev->msi_cap + PCI_MSI_ADDRESS_HI; } static inline uint8_t msi_data_off(const PCIDevice* dev, bool msi64bit) { return dev->msi_cap + (msi64bit ? PCI_MSI_DATA_64 : PCI_MSI_DATA_32); } static inline uint8_t msi_mask_off(const PCIDevice* dev, bool msi64bit) { return dev->msi_cap + (msi64bit ? PCI_MSI_MASK_64 : PCI_MSI_MASK_32); } static inline uint8_t msi_pending_off(const PCIDevice* dev, bool msi64bit) { return dev->msi_cap + (msi64bit ? PCI_MSI_PENDING_64 : PCI_MSI_PENDING_32); } /* * Special API for POWER to configure the vectors through * a side channel. Should never be used by devices. */ void msi_set_message(PCIDevice *dev, MSIMessage msg) { uint16_t flags = pci_get_word(dev->config + msi_flags_off(dev)); bool msi64bit = flags & PCI_MSI_FLAGS_64BIT; if (msi64bit) { pci_set_quad(dev->config + msi_address_lo_off(dev), msg.address); } else { pci_set_long(dev->config + msi_address_lo_off(dev), msg.address); } pci_set_word(dev->config + msi_data_off(dev, msi64bit), msg.data); } MSIMessage msi_get_message(PCIDevice *dev, unsigned int vector) { uint16_t flags = pci_get_word(dev->config + msi_flags_off(dev)); bool msi64bit = flags & PCI_MSI_FLAGS_64BIT; unsigned int nr_vectors = msi_nr_vectors(flags); MSIMessage msg; assert(vector < nr_vectors); if (msi64bit) { msg.address = pci_get_quad(dev->config + msi_address_lo_off(dev)); } else { msg.address = pci_get_long(dev->config + msi_address_lo_off(dev)); } /* upper bit 31:16 is zero */ msg.data = pci_get_word(dev->config + msi_data_off(dev, msi64bit)); if (nr_vectors > 1) { msg.data &= ~(nr_vectors - 1); msg.data |= vector; } return msg; } bool msi_enabled(const PCIDevice *dev) { return msi_present(dev) && (pci_get_word(dev->config + msi_flags_off(dev)) & PCI_MSI_FLAGS_ENABLE); } /* * Make PCI device @dev MSI-capable. * Non-zero @offset puts capability MSI at that offset in PCI config * space. * @nr_vectors is the number of MSI vectors (1, 2, 4, 8, 16 or 32). * If @msi64bit, make the device capable of sending a 64-bit message * address. * If @msi_per_vector_mask, make the device support per-vector masking. * @errp is for returning errors. * Return 0 on success; set @errp and return -errno on error. * * -ENOTSUP means lacking msi support for a msi-capable platform. * -EINVAL means capability overlap, happens when @offset is non-zero, * also means a programming error, except device assignment, which can check * if a real HW is broken. */ int msi_init(struct PCIDevice *dev, uint8_t offset, unsigned int nr_vectors, bool msi64bit, bool msi_per_vector_mask, Error **errp) { unsigned int vectors_order; uint16_t flags; uint8_t cap_size; int config_offset; if (!msi_nonbroken) { error_setg(errp, "MSI is not supported by interrupt controller"); return -ENOTSUP; } MSI_DEV_PRINTF(dev, "init offset: 0x%"PRIx8" vector: %"PRId8 " 64bit %d mask %d\n", offset, nr_vectors, msi64bit, msi_per_vector_mask); assert(!(nr_vectors & (nr_vectors - 1))); /* power of 2 */ assert(nr_vectors > 0); assert(nr_vectors <= PCI_MSI_VECTORS_MAX); /* the nr of MSI vectors is up to 32 */ vectors_order = ctz32(nr_vectors); flags = vectors_order << ctz32(PCI_MSI_FLAGS_QMASK); if (msi64bit) { flags |= PCI_MSI_FLAGS_64BIT; } if (msi_per_vector_mask) { flags |= PCI_MSI_FLAGS_MASKBIT; } cap_size = msi_cap_sizeof(flags); config_offset = pci_add_capability2(dev, PCI_CAP_ID_MSI, offset, cap_size, errp); if (config_offset < 0) { return config_offset; } dev->msi_cap = config_offset; dev->cap_present |= QEMU_PCI_CAP_MSI; pci_set_word(dev->config + msi_flags_off(dev), flags); pci_set_word(dev->wmask + msi_flags_off(dev), PCI_MSI_FLAGS_QSIZE | PCI_MSI_FLAGS_ENABLE); pci_set_long(dev->wmask + msi_address_lo_off(dev), PCI_MSI_ADDRESS_LO_MASK); if (msi64bit) { pci_set_long(dev->wmask + msi_address_hi_off(dev), 0xffffffff); } pci_set_word(dev->wmask + msi_data_off(dev, msi64bit), 0xffff); if (msi_per_vector_mask) { /* Make mask bits 0 to nr_vectors - 1 writable. */ pci_set_long(dev->wmask + msi_mask_off(dev, msi64bit), 0xffffffff >> (PCI_MSI_VECTORS_MAX - nr_vectors)); } return 0; } void msi_uninit(struct PCIDevice *dev) { uint16_t flags; uint8_t cap_size; if (!msi_present(dev)) { return; } flags = pci_get_word(dev->config + msi_flags_off(dev)); cap_size = msi_cap_sizeof(flags); pci_del_capability(dev, PCI_CAP_ID_MSI, cap_size); dev->cap_present &= ~QEMU_PCI_CAP_MSI; MSI_DEV_PRINTF(dev, "uninit\n"); } void msi_reset(PCIDevice *dev) { uint16_t flags; bool msi64bit; if (!msi_present(dev)) { return; } flags = pci_get_word(dev->config + msi_flags_off(dev)); flags &= ~(PCI_MSI_FLAGS_QSIZE | PCI_MSI_FLAGS_ENABLE); msi64bit = flags & PCI_MSI_FLAGS_64BIT; pci_set_word(dev->config + msi_flags_off(dev), flags); pci_set_long(dev->config + msi_address_lo_off(dev), 0); if (msi64bit) { pci_set_long(dev->config + msi_address_hi_off(dev), 0); } pci_set_word(dev->config + msi_data_off(dev, msi64bit), 0); if (flags & PCI_MSI_FLAGS_MASKBIT) { pci_set_long(dev->config + msi_mask_off(dev, msi64bit), 0); pci_set_long(dev->config + msi_pending_off(dev, msi64bit), 0); } MSI_DEV_PRINTF(dev, "reset\n"); } static bool msi_is_masked(const PCIDevice *dev, unsigned int vector) { uint16_t flags = pci_get_word(dev->config + msi_flags_off(dev)); uint32_t mask, data; bool msi64bit = flags & PCI_MSI_FLAGS_64BIT; assert(vector < PCI_MSI_VECTORS_MAX); if (!(flags & PCI_MSI_FLAGS_MASKBIT)) { return false; } data = pci_get_word(dev->config + msi_data_off(dev, msi64bit)); if (xen_is_pirq_msi(data)) { return false; } mask = pci_get_long(dev->config + msi_mask_off(dev, flags & PCI_MSI_FLAGS_64BIT)); return mask & (1U << vector); } void msi_notify(PCIDevice *dev, unsigned int vector) { uint16_t flags = pci_get_word(dev->config + msi_flags_off(dev)); bool msi64bit = flags & PCI_MSI_FLAGS_64BIT; unsigned int nr_vectors = msi_nr_vectors(flags); MSIMessage msg; assert(vector < nr_vectors); if (msi_is_masked(dev, vector)) { assert(flags & PCI_MSI_FLAGS_MASKBIT); pci_long_test_and_set_mask( dev->config + msi_pending_off(dev, msi64bit), 1U << vector); MSI_DEV_PRINTF(dev, "pending vector 0x%x\n", vector); return; } msg = msi_get_message(dev, vector); MSI_DEV_PRINTF(dev, "notify vector 0x%x" " address: 0x%"PRIx64" data: 0x%"PRIx32"\n", vector, msg.address, msg.data); msi_send_message(dev, msg); } void msi_send_message(PCIDevice *dev, MSIMessage msg) { MemTxAttrs attrs = {}; attrs.requester_id = pci_requester_id(dev); address_space_stl_le(&dev->bus_master_as, msg.address, msg.data, attrs, NULL); } /* Normally called by pci_default_write_config(). */ void msi_write_config(PCIDevice *dev, uint32_t addr, uint32_t val, int len) { uint16_t flags = pci_get_word(dev->config + msi_flags_off(dev)); bool msi64bit = flags & PCI_MSI_FLAGS_64BIT; bool msi_per_vector_mask = flags & PCI_MSI_FLAGS_MASKBIT; unsigned int nr_vectors; uint8_t log_num_vecs; uint8_t log_max_vecs; unsigned int vector; uint32_t pending; if (!msi_present(dev) || !ranges_overlap(addr, len, dev->msi_cap, msi_cap_sizeof(flags))) { return; } #ifdef MSI_DEBUG MSI_DEV_PRINTF(dev, "addr 0x%"PRIx32" val 0x%"PRIx32" len %d\n", addr, val, len); MSI_DEV_PRINTF(dev, "ctrl: 0x%"PRIx16" address: 0x%"PRIx32, flags, pci_get_long(dev->config + msi_address_lo_off(dev))); if (msi64bit) { fprintf(stderr, " address-hi: 0x%"PRIx32, pci_get_long(dev->config + msi_address_hi_off(dev))); } fprintf(stderr, " data: 0x%"PRIx16, pci_get_word(dev->config + msi_data_off(dev, msi64bit))); if (flags & PCI_MSI_FLAGS_MASKBIT) { fprintf(stderr, " mask 0x%"PRIx32" pending 0x%"PRIx32, pci_get_long(dev->config + msi_mask_off(dev, msi64bit)), pci_get_long(dev->config + msi_pending_off(dev, msi64bit))); } fprintf(stderr, "\n"); #endif if (!(flags & PCI_MSI_FLAGS_ENABLE)) { return; } /* * Now MSI is enabled, clear INTx# interrupts. * the driver is prohibited from writing enable bit to mask * a service request. But the guest OS could do this. * So we just discard the interrupts as moderate fallback. * * 6.8.3.3. Enabling Operation * While enabled for MSI or MSI-X operation, a function is prohibited * from using its INTx# pin (if implemented) to request * service (MSI, MSI-X, and INTx# are mutually exclusive). */ pci_device_deassert_intx(dev); /* * nr_vectors might be set bigger than capable. So clamp it. * This is not legal by spec, so we can do anything we like, * just don't crash the host */ log_num_vecs = (flags & PCI_MSI_FLAGS_QSIZE) >> ctz32(PCI_MSI_FLAGS_QSIZE); log_max_vecs = (flags & PCI_MSI_FLAGS_QMASK) >> ctz32(PCI_MSI_FLAGS_QMASK); if (log_num_vecs > log_max_vecs) { flags &= ~PCI_MSI_FLAGS_QSIZE; flags |= log_max_vecs << ctz32(PCI_MSI_FLAGS_QSIZE); pci_set_word(dev->config + msi_flags_off(dev), flags); } if (!msi_per_vector_mask) { /* if per vector masking isn't supported, there is no pending interrupt. */ return; } nr_vectors = msi_nr_vectors(flags); /* This will discard pending interrupts, if any. */ pending = pci_get_long(dev->config + msi_pending_off(dev, msi64bit)); pending &= 0xffffffff >> (PCI_MSI_VECTORS_MAX - nr_vectors); pci_set_long(dev->config + msi_pending_off(dev, msi64bit), pending); /* deliver pending interrupts which are unmasked */ for (vector = 0; vector < nr_vectors; ++vector) { if (msi_is_masked(dev, vector) || !(pending & (1U << vector))) { continue; } pci_long_test_and_clear_mask( dev->config + msi_pending_off(dev, msi64bit), 1U << vector); msi_notify(dev, vector); } } unsigned int msi_nr_vectors_allocated(const PCIDevice *dev) { uint16_t flags = pci_get_word(dev->config + msi_flags_off(dev)); return msi_nr_vectors(flags); }