Files
Xenia-Canary/src/xenia/gpu/gl4/circular_buffer.cc
2015-06-27 11:25:56 -07:00

152 lines
4.6 KiB
C++

/**
******************************************************************************
* Xenia : Xbox 360 Emulator Research Project *
******************************************************************************
* Copyright 2014 Ben Vanik. All rights reserved. *
* Released under the BSD license - see LICENSE in the root for more details. *
******************************************************************************
*/
#include "xenia/gpu/gl4/circular_buffer.h"
#include "xenia/base/assert.h"
#include "xenia/base/math.h"
#include "xenia/gpu/gl4/gl4_gpu_flags.h"
#include "xenia/gpu/gpu_flags.h"
namespace xe {
namespace gpu {
namespace gl4 {
extern "C" GLEWContext* glewGetContext();
extern "C" WGLEWContext* wglewGetContext();
CircularBuffer::CircularBuffer(size_t capacity, size_t alignment)
: capacity_(capacity),
alignment_(alignment),
write_head_(0),
dirty_start_(UINT64_MAX),
dirty_end_(0),
buffer_(0),
gpu_base_(0),
host_base_(nullptr) {}
CircularBuffer::~CircularBuffer() { Shutdown(); }
bool CircularBuffer::Initialize() {
glCreateBuffers(1, &buffer_);
glNamedBufferStorage(buffer_, capacity_, nullptr,
GL_MAP_WRITE_BIT | GL_MAP_PERSISTENT_BIT);
host_base_ = reinterpret_cast<uint8_t*>(glMapNamedBufferRange(
buffer_, 0, capacity_,
GL_MAP_WRITE_BIT | GL_MAP_FLUSH_EXPLICIT_BIT | GL_MAP_PERSISTENT_BIT));
assert_not_null(host_base_);
if (!host_base_) {
return false;
}
if (FLAGS_vendor_gl_extensions && GLEW_NV_shader_buffer_load) {
// To use this bindlessly we must make it resident.
glMakeNamedBufferResidentNV(buffer_, GL_READ_ONLY);
glGetNamedBufferParameterui64vNV(buffer_, GL_BUFFER_GPU_ADDRESS_NV,
&gpu_base_);
}
return true;
}
void CircularBuffer::Shutdown() {
if (!buffer_) {
return;
}
glUnmapNamedBuffer(buffer_);
if (FLAGS_vendor_gl_extensions && GLEW_NV_shader_buffer_load) {
glMakeNamedBufferNonResidentNV(buffer_);
}
glDeleteBuffers(1, &buffer_);
buffer_ = 0;
}
bool CircularBuffer::CanAcquire(size_t length) {
size_t aligned_length = xe::round_up(length, alignment_);
return write_head_ + aligned_length <= capacity_;
}
CircularBuffer::Allocation CircularBuffer::Acquire(size_t length) {
// Addresses must always be % 256.
size_t aligned_length = xe::round_up(length, alignment_);
assert_true(aligned_length <= capacity_, "Request too large");
if (write_head_ + aligned_length > capacity_) {
// Flush and wait.
WaitUntilClean();
}
Allocation allocation;
allocation.host_ptr = host_base_ + write_head_;
allocation.gpu_ptr = gpu_base_ + write_head_;
allocation.offset = write_head_;
allocation.length = length;
allocation.aligned_length = aligned_length;
allocation.cache_key = 0;
write_head_ += aligned_length;
return allocation;
}
bool CircularBuffer::AcquireCached(uint32_t key, size_t length,
Allocation* out_allocation) {
uint64_t full_key = key | (length << 32);
auto& it = allocation_cache_.find(full_key);
if (it != allocation_cache_.end()) {
uintptr_t write_head = it->second;
size_t aligned_length = xe::round_up(length, alignment_);
out_allocation->host_ptr = host_base_ + write_head;
out_allocation->gpu_ptr = gpu_base_ + write_head;
out_allocation->offset = write_head;
out_allocation->length = length;
out_allocation->aligned_length = aligned_length;
out_allocation->cache_key = full_key;
return true;
} else {
*out_allocation = Acquire(length);
out_allocation->cache_key = full_key;
return false;
}
}
void CircularBuffer::Discard(Allocation allocation) {
write_head_ -= allocation.aligned_length;
}
void CircularBuffer::Commit(Allocation allocation) {
uintptr_t start = allocation.gpu_ptr - gpu_base_;
uintptr_t end = start + allocation.aligned_length;
dirty_start_ = std::min(dirty_start_, start);
dirty_end_ = std::max(dirty_end_, end);
assert_true(dirty_end_ <= capacity_);
if (allocation.cache_key) {
allocation_cache_.insert({allocation.cache_key, allocation.offset});
}
}
void CircularBuffer::Flush() {
if (dirty_start_ == dirty_end_ || dirty_start_ == UINT64_MAX) {
return;
}
glFlushMappedNamedBufferRange(buffer_, dirty_start_,
dirty_end_ - dirty_start_);
dirty_start_ = UINT64_MAX;
dirty_end_ = 0;
}
void CircularBuffer::ClearCache() { allocation_cache_.clear(); }
void CircularBuffer::WaitUntilClean() {
Flush();
glFinish();
write_head_ = 0;
ClearCache();
}
} // namespace gl4
} // namespace gpu
} // namespace xe