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-rw-r--r--hw/pci/msi.c395
1 files changed, 395 insertions, 0 deletions
diff --git a/hw/pci/msi.c b/hw/pci/msi.c
new file mode 100644
index 0000000..2a04d18
--- /dev/null
+++ b/hw/pci/msi.c
@@ -0,0 +1,395 @@
+/*
+ * 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"
+
+/* Eventually those constants should go to Linux pci_regs.h */
+#define PCI_MSI_PENDING_32 0x10
+#define PCI_MSI_PENDING_64 0x14
+
+/* 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) >> (ffs(PCI_MSI_FLAGS_QSIZE) - 1));
+}
+
+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 = ffs(nr_vectors) - 1;
+
+ flags = vectors_order << (ffs(PCI_MSI_FLAGS_QMASK) - 1);
+ 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);
+ stl_le_phys(msg.address, msg.data);
+}
+
+/* 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) >> (ffs(PCI_MSI_FLAGS_QSIZE) - 1);
+ log_max_vecs =
+ (flags & PCI_MSI_FLAGS_QMASK) >> (ffs(PCI_MSI_FLAGS_QMASK) - 1);
+ if (log_num_vecs > log_max_vecs) {
+ flags &= ~PCI_MSI_FLAGS_QSIZE;
+ flags |= log_max_vecs << (ffs(PCI_MSI_FLAGS_QSIZE) - 1);
+ 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);
+}
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