diff options
Diffstat (limited to 'src/hw/pci/msi.c')
| -rw-r--r-- | src/hw/pci/msi.c | 400 |
1 files changed, 400 insertions, 0 deletions
diff --git a/src/hw/pci/msi.c b/src/hw/pci/msi.c new file mode 100644 index 0000000..c1dd531 --- /dev/null +++ b/src/hw/pci/msi.c @@ -0,0 +1,400 @@ +/* + * msi.c + * + * Copyright (c) 2010 Isaku Yamahata <yamahata at valinux co jp> + * 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 <http://www.gnu.org/licenses/>. + */ + +#include "hw/pci/msi.h" +#include "qemu/range.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 controller to declare MSI/MSI-X support */ +bool msi_supported; + +/* 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); +} + +int msi_init(struct PCIDevice *dev, uint8_t offset, + unsigned int nr_vectors, bool msi64bit, bool msi_per_vector_mask) +{ + unsigned int vectors_order; + uint16_t flags; + uint8_t cap_size; + int config_offset; + + if (!msi_supported) { + 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_capability(dev, PCI_CAP_ID_MSI, offset, cap_size); + 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 config_offset; +} + +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; + assert(vector < PCI_MSI_VECTORS_MAX); + + if (!(flags & PCI_MSI_FLAGS_MASKBIT)) { + 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); +} |
