diff options
Diffstat (limited to 'qemu/hw/misc/mips_itu.c')
| -rw-r--r-- | qemu/hw/misc/mips_itu.c | 521 |
1 files changed, 521 insertions, 0 deletions
diff --git a/qemu/hw/misc/mips_itu.c b/qemu/hw/misc/mips_itu.c new file mode 100644 index 000000000..da5455062 --- /dev/null +++ b/qemu/hw/misc/mips_itu.c @@ -0,0 +1,521 @@ +/* + * 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_CELL_PV_MAX_VAL 0xFFFF + +#define ITC_CELL_TAG_FIFO_DEPTH 28 +#define ITC_CELL_TAG_FIFO_PTR 18 +#define ITC_CELL_TAG_FIFO 17 +#define ITC_CELL_TAG_T 16 +#define ITC_CELL_TAG_F 1 +#define ITC_CELL_TAG_E 0 + +#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 + +typedef enum ITCView { + ITCVIEW_BYPASS = 0, + ITCVIEW_CONTROL = 1, + ITCVIEW_EF_SYNC = 2, + ITCVIEW_EF_TRY = 3, + ITCVIEW_PV_SYNC = 4, + ITCVIEW_PV_TRY = 5 +} ITCView; + +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; + + if (index >= ITC_ADDRESSMAP_NUM) { + qemu_log_mask(LOG_GUEST_ERROR, "Read 0x%" PRIx64 "\n", addr); + return 0; + } + + return tag->ITCAddressMap[index]; +} + +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 inline ITCView get_itc_view(hwaddr addr) +{ + return (addr >> 3) & 0xf; +} + +static inline int get_cell_stride_shift(const MIPSITUState *s) +{ + /* Minimum interval (for EntryGain = 0) is 128 B */ + return 7 + (s->ITCAddressMap[1] & ITC_AM1_ENTRY_GRAIN_MASK); +} + +static inline ITCStorageCell *get_cell(MIPSITUState *s, + hwaddr addr) +{ + uint32_t cell_idx = addr >> get_cell_stride_shift(s); + uint32_t num_cells = get_num_cells(s); + + if (cell_idx >= num_cells) { + cell_idx = num_cells - 1; + } + + return &s->cell[cell_idx]; +} + +static void wake_blocked_threads(ITCStorageCell *c) +{ + CPUState *cs; + CPU_FOREACH(cs) { + if (cs->halted && (c->blocked_threads & (1ULL << cs->cpu_index))) { + cpu_interrupt(cs, CPU_INTERRUPT_WAKE); + } + } + c->blocked_threads = 0; +} + +static void QEMU_NORETURN block_thread_and_exit(ITCStorageCell *c) +{ + c->blocked_threads |= 1ULL << current_cpu->cpu_index; + cpu_restore_state(current_cpu, current_cpu->mem_io_pc); + current_cpu->halted = 1; + current_cpu->exception_index = EXCP_HLT; + cpu_loop_exit(current_cpu); +} + +/* ITC Bypass View */ + +static inline uint64_t view_bypass_read(ITCStorageCell *c) +{ + if (c->tag.FIFO) { + return c->data[c->fifo_out]; + } else { + return c->data[0]; + } +} + +static inline void view_bypass_write(ITCStorageCell *c, uint64_t val) +{ + if (c->tag.FIFO && (c->tag.FIFOPtr > 0)) { + int idx = (c->fifo_out + c->tag.FIFOPtr - 1) % ITC_CELL_DEPTH; + c->data[idx] = val; + } + + /* ignore a write to the semaphore cell */ +} + +/* ITC Control View */ + +static inline uint64_t view_control_read(ITCStorageCell *c) +{ + return ((uint64_t)c->tag.FIFODepth << ITC_CELL_TAG_FIFO_DEPTH) | + (c->tag.FIFOPtr << ITC_CELL_TAG_FIFO_PTR) | + (c->tag.FIFO << ITC_CELL_TAG_FIFO) | + (c->tag.T << ITC_CELL_TAG_T) | + (c->tag.E << ITC_CELL_TAG_E) | + (c->tag.F << ITC_CELL_TAG_F); +} + +static inline void view_control_write(ITCStorageCell *c, uint64_t val) +{ + c->tag.T = (val >> ITC_CELL_TAG_T) & 1; + c->tag.E = (val >> ITC_CELL_TAG_E) & 1; + c->tag.F = (val >> ITC_CELL_TAG_F) & 1; + + if (c->tag.E) { + c->tag.FIFOPtr = 0; + } +} + +/* ITC Empty/Full View */ + +static uint64_t view_ef_common_read(ITCStorageCell *c, bool blocking) +{ + uint64_t ret = 0; + + if (!c->tag.FIFO) { + return 0; + } + + c->tag.F = 0; + + if (blocking && c->tag.E) { + block_thread_and_exit(c); + } + + if (c->blocked_threads) { + wake_blocked_threads(c); + } + + if (c->tag.FIFOPtr > 0) { + ret = c->data[c->fifo_out]; + c->fifo_out = (c->fifo_out + 1) % ITC_CELL_DEPTH; + c->tag.FIFOPtr--; + } + + if (c->tag.FIFOPtr == 0) { + c->tag.E = 1; + } + + return ret; +} + +static uint64_t view_ef_sync_read(ITCStorageCell *c) +{ + return view_ef_common_read(c, true); +} + +static uint64_t view_ef_try_read(ITCStorageCell *c) +{ + return view_ef_common_read(c, false); +} + +static inline void view_ef_common_write(ITCStorageCell *c, uint64_t val, + bool blocking) +{ + if (!c->tag.FIFO) { + return; + } + + c->tag.E = 0; + + if (blocking && c->tag.F) { + block_thread_and_exit(c); + } + + if (c->blocked_threads) { + wake_blocked_threads(c); + } + + if (c->tag.FIFOPtr < ITC_CELL_DEPTH) { + int idx = (c->fifo_out + c->tag.FIFOPtr) % ITC_CELL_DEPTH; + c->data[idx] = val; + c->tag.FIFOPtr++; + } + + if (c->tag.FIFOPtr == ITC_CELL_DEPTH) { + c->tag.F = 1; + } +} + +static void view_ef_sync_write(ITCStorageCell *c, uint64_t val) +{ + view_ef_common_write(c, val, true); +} + +static void view_ef_try_write(ITCStorageCell *c, uint64_t val) +{ + view_ef_common_write(c, val, false); +} + +/* ITC P/V View */ + +static uint64_t view_pv_common_read(ITCStorageCell *c, bool blocking) +{ + uint64_t ret = c->data[0]; + + if (c->tag.FIFO) { + return 0; + } + + if (c->data[0] > 0) { + c->data[0]--; + } else if (blocking) { + block_thread_and_exit(c); + } + + return ret; +} + +static uint64_t view_pv_sync_read(ITCStorageCell *c) +{ + return view_pv_common_read(c, true); +} + +static uint64_t view_pv_try_read(ITCStorageCell *c) +{ + return view_pv_common_read(c, false); +} + +static inline void view_pv_common_write(ITCStorageCell *c) +{ + if (c->tag.FIFO) { + return; + } + + if (c->data[0] < ITC_CELL_PV_MAX_VAL) { + c->data[0]++; + } + + if (c->blocked_threads) { + wake_blocked_threads(c); + } +} + +static void view_pv_sync_write(ITCStorageCell *c) +{ + view_pv_common_write(c); +} + +static void view_pv_try_write(ITCStorageCell *c) +{ + view_pv_common_write(c); +} + +static uint64_t itc_storage_read(void *opaque, hwaddr addr, unsigned size) +{ + MIPSITUState *s = (MIPSITUState *)opaque; + ITCStorageCell *cell = get_cell(s, addr); + ITCView view = get_itc_view(addr); + uint64_t ret = -1; + + switch (view) { + case ITCVIEW_BYPASS: + ret = view_bypass_read(cell); + break; + case ITCVIEW_CONTROL: + ret = view_control_read(cell); + break; + case ITCVIEW_EF_SYNC: + ret = view_ef_sync_read(cell); + break; + case ITCVIEW_EF_TRY: + ret = view_ef_try_read(cell); + break; + case ITCVIEW_PV_SYNC: + ret = view_pv_sync_read(cell); + break; + case ITCVIEW_PV_TRY: + ret = view_pv_try_read(cell); + break; + default: + qemu_log_mask(LOG_GUEST_ERROR, + "itc_storage_read: Bad ITC View %d\n", (int)view); + break; + } + + return ret; +} + +static void itc_storage_write(void *opaque, hwaddr addr, uint64_t data, + unsigned size) +{ + MIPSITUState *s = (MIPSITUState *)opaque; + ITCStorageCell *cell = get_cell(s, addr); + ITCView view = get_itc_view(addr); + + switch (view) { + case ITCVIEW_BYPASS: + view_bypass_write(cell, data); + break; + case ITCVIEW_CONTROL: + view_control_write(cell, data); + break; + case ITCVIEW_EF_SYNC: + view_ef_sync_write(cell, data); + break; + case ITCVIEW_EF_TRY: + view_ef_try_write(cell, data); + break; + case ITCVIEW_PV_SYNC: + view_pv_sync_write(cell); + break; + case ITCVIEW_PV_TRY: + view_pv_try_write(cell); + break; + default: + qemu_log_mask(LOG_GUEST_ERROR, + "itc_storage_write: Bad ITC View %d\n", (int)view); + break; + } + +} + +static const MemoryRegionOps itc_storage_ops = { + .read = itc_storage_read, + .write = itc_storage_write, + .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) |