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-rw-r--r--hw/misc/mips_itu.c214
1 files changed, 214 insertions, 0 deletions
diff --git a/hw/misc/mips_itu.c b/hw/misc/mips_itu.c
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+/*
+ * Inter-Thread Communication Unit emulation.
+ *
+ * Copyright (c) 2016 Imagination Technologies
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "qemu/osdep.h"
+#include "qapi/error.h"
+#include "hw/hw.h"
+#include "hw/sysbus.h"
+#include "sysemu/sysemu.h"
+#include "hw/misc/mips_itu.h"
+
+#define ITC_TAG_ADDRSPACE_SZ (ITC_ADDRESSMAP_NUM * 8)
+/* Initialize as 4kB area to fit all 32 cells with default 128B grain.
+ Storage may be resized by the software. */
+#define ITC_STORAGE_ADDRSPACE_SZ 0x1000
+
+#define ITC_FIFO_NUM_MAX 16
+#define ITC_SEMAPH_NUM_MAX 16
+#define ITC_AM1_NUMENTRIES_OFS 20
+
+#define ITC_AM0_BASE_ADDRESS_MASK 0xFFFFFC00ULL
+#define ITC_AM0_EN_MASK 0x1
+
+#define ITC_AM1_ADDR_MASK_MASK 0x1FC00
+#define ITC_AM1_ENTRY_GRAIN_MASK 0x7
+
+MemoryRegion *mips_itu_get_tag_region(MIPSITUState *itu)
+{
+ return &itu->tag_io;
+}
+
+static uint64_t itc_tag_read(void *opaque, hwaddr addr, unsigned size)
+{
+ MIPSITUState *tag = (MIPSITUState *)opaque;
+ uint64_t index = addr >> 3;
+ uint64_t ret = 0;
+
+ switch (index) {
+ case 0 ... ITC_ADDRESSMAP_NUM:
+ ret = tag->ITCAddressMap[index];
+ break;
+ default:
+ qemu_log_mask(LOG_GUEST_ERROR, "Read 0x%" PRIx64 "\n", addr);
+ break;
+ }
+
+ return ret;
+}
+
+static void itc_reconfigure(MIPSITUState *tag)
+{
+ uint64_t *am = &tag->ITCAddressMap[0];
+ MemoryRegion *mr = &tag->storage_io;
+ hwaddr address = am[0] & ITC_AM0_BASE_ADDRESS_MASK;
+ uint64_t size = (1 << 10) + (am[1] & ITC_AM1_ADDR_MASK_MASK);
+ bool is_enabled = (am[0] & ITC_AM0_EN_MASK) != 0;
+
+ memory_region_transaction_begin();
+ if (!(size & (size - 1))) {
+ memory_region_set_size(mr, size);
+ }
+ memory_region_set_address(mr, address);
+ memory_region_set_enabled(mr, is_enabled);
+ memory_region_transaction_commit();
+}
+
+static void itc_tag_write(void *opaque, hwaddr addr,
+ uint64_t data, unsigned size)
+{
+ MIPSITUState *tag = (MIPSITUState *)opaque;
+ uint64_t *am = &tag->ITCAddressMap[0];
+ uint64_t am_old, mask;
+ uint64_t index = addr >> 3;
+
+ switch (index) {
+ case 0:
+ mask = ITC_AM0_BASE_ADDRESS_MASK | ITC_AM0_EN_MASK;
+ break;
+ case 1:
+ mask = ITC_AM1_ADDR_MASK_MASK | ITC_AM1_ENTRY_GRAIN_MASK;
+ break;
+ default:
+ qemu_log_mask(LOG_GUEST_ERROR, "Bad write 0x%" PRIx64 "\n", addr);
+ return;
+ }
+
+ am_old = am[index];
+ am[index] = (data & mask) | (am_old & ~mask);
+ if (am_old != am[index]) {
+ itc_reconfigure(tag);
+ }
+}
+
+static const MemoryRegionOps itc_tag_ops = {
+ .read = itc_tag_read,
+ .write = itc_tag_write,
+ .impl = {
+ .max_access_size = 8,
+ },
+ .endianness = DEVICE_NATIVE_ENDIAN,
+};
+
+static inline uint32_t get_num_cells(MIPSITUState *s)
+{
+ return s->num_fifo + s->num_semaphores;
+}
+
+static const MemoryRegionOps itc_storage_ops = {
+ .endianness = DEVICE_NATIVE_ENDIAN,
+};
+
+static void itc_reset_cells(MIPSITUState *s)
+{
+ int i;
+
+ memset(s->cell, 0, get_num_cells(s) * sizeof(s->cell[0]));
+
+ for (i = 0; i < s->num_fifo; i++) {
+ s->cell[i].tag.E = 1;
+ s->cell[i].tag.FIFO = 1;
+ s->cell[i].tag.FIFODepth = ITC_CELL_DEPTH_SHIFT;
+ }
+}
+
+static void mips_itu_init(Object *obj)
+{
+ SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
+ MIPSITUState *s = MIPS_ITU(obj);
+
+ memory_region_init_io(&s->storage_io, OBJECT(s), &itc_storage_ops, s,
+ "mips-itc-storage", ITC_STORAGE_ADDRSPACE_SZ);
+ sysbus_init_mmio(sbd, &s->storage_io);
+
+ memory_region_init_io(&s->tag_io, OBJECT(s), &itc_tag_ops, s,
+ "mips-itc-tag", ITC_TAG_ADDRSPACE_SZ);
+}
+
+static void mips_itu_realize(DeviceState *dev, Error **errp)
+{
+ MIPSITUState *s = MIPS_ITU(dev);
+
+ if (s->num_fifo > ITC_FIFO_NUM_MAX) {
+ error_setg(errp, "Exceed maximum number of FIFO cells: %d",
+ s->num_fifo);
+ return;
+ }
+ if (s->num_semaphores > ITC_SEMAPH_NUM_MAX) {
+ error_setg(errp, "Exceed maximum number of Semaphore cells: %d",
+ s->num_semaphores);
+ return;
+ }
+
+ s->cell = g_new(ITCStorageCell, get_num_cells(s));
+}
+
+static void mips_itu_reset(DeviceState *dev)
+{
+ MIPSITUState *s = MIPS_ITU(dev);
+
+ s->ITCAddressMap[0] = 0;
+ s->ITCAddressMap[1] =
+ ((ITC_STORAGE_ADDRSPACE_SZ - 1) & ITC_AM1_ADDR_MASK_MASK) |
+ (get_num_cells(s) << ITC_AM1_NUMENTRIES_OFS);
+ itc_reconfigure(s);
+
+ itc_reset_cells(s);
+}
+
+static Property mips_itu_properties[] = {
+ DEFINE_PROP_INT32("num-fifo", MIPSITUState, num_fifo,
+ ITC_FIFO_NUM_MAX),
+ DEFINE_PROP_INT32("num-semaphores", MIPSITUState, num_semaphores,
+ ITC_SEMAPH_NUM_MAX),
+ DEFINE_PROP_END_OF_LIST(),
+};
+
+static void mips_itu_class_init(ObjectClass *klass, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(klass);
+
+ dc->props = mips_itu_properties;
+ dc->realize = mips_itu_realize;
+ dc->reset = mips_itu_reset;
+}
+
+static const TypeInfo mips_itu_info = {
+ .name = TYPE_MIPS_ITU,
+ .parent = TYPE_SYS_BUS_DEVICE,
+ .instance_size = sizeof(MIPSITUState),
+ .instance_init = mips_itu_init,
+ .class_init = mips_itu_class_init,
+};
+
+static void mips_itu_register_types(void)
+{
+ type_register_static(&mips_itu_info);
+}
+
+type_init(mips_itu_register_types)
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