From a3abf81afec540cf908002546eb462ec5b40407a Mon Sep 17 00:00:00 2001 From: tangxifan Date: Wed, 23 Sep 2020 21:25:06 -0600 Subject: [PATCH] [OpenFPGA Tool] Support on set signals and smart selection between reset and set signal for fast configuration --- .../fpga_verilog/verilog_top_testbench.cpp | 135 ++++++++++++++++-- 1 file changed, 127 insertions(+), 8 deletions(-) diff --git a/openfpga/src/fpga_verilog/verilog_top_testbench.cpp b/openfpga/src/fpga_verilog/verilog_top_testbench.cpp index 763f7800e..d6f7d1075 100644 --- a/openfpga/src/fpga_verilog/verilog_top_testbench.cpp +++ b/openfpga/src/fpga_verilog/verilog_top_testbench.cpp @@ -1135,6 +1135,89 @@ void print_verilog_top_testbench_vanilla_bitstream(std::fstream& fp, print_verilog_comment(fp, "----- End bitstream loading during configuration phase -----"); } +/******************************************************************** + * Decide if we should use reset or set signal to acheive fast configuration + * - If only one type signal is specified, we use that type + * For example, only reset signal is defined, we will use reset + * - If both are defined, pick the one that will bring bigger reduction + * i.e., larger number of configuration bits can be skipped + *******************************************************************/ +static +bool find_bit_value_to_skip_for_fast_configuration(const e_config_protocol_type& config_protocol_type, + const bool& fast_configuration, + const std::vector& global_prog_reset_ports, + const std::vector& global_prog_set_ports, + const BitstreamManager& bitstream_manager, + const FabricBitstream& fabric_bitstream) { + + /* Early exit conditions */ + if (!global_prog_reset_ports.empty() && global_prog_set_ports.empty()) { + return false; + } else if (!global_prog_set_ports.empty() && global_prog_reset_ports.empty()) { + return true; + } else if (global_prog_set_ports.empty() && global_prog_reset_ports.empty()) { + /* If both types of ports are not defined, the fast configuration should be turned off */ + VTR_ASSERT(false == fast_configuration); + return false; + } + + VTR_ASSERT(!global_prog_set_ports.empty() && !global_prog_reset_ports.empty()); + bool bit_value_to_skip = false; + + size_t num_ones_to_skip = 0; + size_t num_zeros_to_skip = 0; + + /* Branch on the type of configuration protocol */ + switch (config_protocol_type) { + case CONFIG_MEM_STANDALONE: + break; + case CONFIG_MEM_SCAN_CHAIN: { + /* We can only skip the ones/zeros at the beginning of the bitstream */ + /* Count how many logic '1' bits we can skip */ + for (const FabricBitId& bit_id : fabric_bitstream.bits()) { + if (false == bitstream_manager.bit_value(fabric_bitstream.config_bit(bit_id))) { + break; + } + VTR_ASSERT(true == bitstream_manager.bit_value(fabric_bitstream.config_bit(bit_id))); + num_ones_to_skip++; + } + /* Count how many logic '0' bits we can skip */ + for (const FabricBitId& bit_id : fabric_bitstream.bits()) { + if (true == bitstream_manager.bit_value(fabric_bitstream.config_bit(bit_id))) { + break; + } + VTR_ASSERT(false == bitstream_manager.bit_value(fabric_bitstream.config_bit(bit_id))); + num_zeros_to_skip++; + } + break; + } + case CONFIG_MEM_MEMORY_BANK: + case CONFIG_MEM_FRAME_BASED: { + /* Count how many logic '1' and logic '0' bits we can skip */ + for (const FabricBitId& bit_id : fabric_bitstream.bits()) { + if (false == bitstream_manager.bit_value(fabric_bitstream.config_bit(bit_id))) { + num_zeros_to_skip++; + } else { + VTR_ASSERT(true == bitstream_manager.bit_value(fabric_bitstream.config_bit(bit_id))); + num_ones_to_skip++; + } + } + break; + } + default: + VTR_LOGF_ERROR(__FILE__, __LINE__, + "Invalid SRAM organization type!\n"); + exit(1); + } + + /* By default, we prefer to skip zeros (when the numbers are the same */ + if (num_ones_to_skip > num_zeros_to_skip) { + bit_value_to_skip = true; + } + + return bit_value_to_skip; +} + /******************************************************************** * Print stimulus for a FPGA fabric with a configuration chain protocol * where configuration bits are programming in serial (one by one) @@ -1150,6 +1233,7 @@ void print_verilog_top_testbench_vanilla_bitstream(std::fstream& fp, static void print_verilog_top_testbench_configuration_chain_bitstream(std::fstream& fp, const bool& fast_configuration, + const bool& bit_value_to_skip, const BitstreamManager& bitstream_manager, const FabricBitstream& fabric_bitstream) { /* Validate the file stream */ @@ -1174,13 +1258,14 @@ void print_verilog_top_testbench_configuration_chain_bitstream(std::fstream& fp, fp << std::endl; + /* Attention: when the fast configuration is enabled, we will start from the first bit '1' * This requires a reset signal (as we forced in the first clock cycle) */ bool start_config = false; for (const FabricBitId& bit_id : fabric_bitstream.bits()) { if ( (false == start_config) - && (true == bitstream_manager.bit_value(fabric_bitstream.config_bit(bit_id)))) { + && (bit_value_to_skip != bitstream_manager.bit_value(fabric_bitstream.config_bit(bit_id)))) { start_config = true; } @@ -1221,6 +1306,7 @@ void print_verilog_top_testbench_configuration_chain_bitstream(std::fstream& fp, static void print_verilog_top_testbench_memory_bank_bitstream(std::fstream& fp, const bool& fast_configuration, + const bool& bit_value_to_skip, const ModuleManager& module_manager, const ModuleId& top_module, const FabricBitstream& fabric_bitstream) { @@ -1272,7 +1358,7 @@ void print_verilog_top_testbench_memory_bank_bitstream(std::fstream& fp, for (const FabricBitId& bit_id : fabric_bitstream.bits()) { /* When fast configuration is enabled, we skip zero data_in values */ if ((true == fast_configuration) - && (false == fabric_bitstream.bit_din(bit_id))) { + && (bit_value_to_skip == fabric_bitstream.bit_din(bit_id))) { continue; } @@ -1326,6 +1412,7 @@ void print_verilog_top_testbench_memory_bank_bitstream(std::fstream& fp, static void print_verilog_top_testbench_frame_decoder_bitstream(std::fstream& fp, const bool& fast_configuration, + const bool& bit_value_to_skip, const ModuleManager& module_manager, const ModuleId& top_module, const FabricBitstream& fabric_bitstream) { @@ -1368,7 +1455,7 @@ void print_verilog_top_testbench_frame_decoder_bitstream(std::fstream& fp, for (const FabricBitId& bit_id : fabric_bitstream.bits()) { /* When fast configuration is enabled, we skip zero data_in values */ if ((true == fast_configuration) - && (false == fabric_bitstream.bit_din(bit_id))) { + && (bit_value_to_skip == fabric_bitstream.bit_din(bit_id))) { continue; } @@ -1424,30 +1511,61 @@ void print_verilog_top_testbench_frame_decoder_bitstream(std::fstream& fp, *******************************************************************/ static void print_verilog_top_testbench_bitstream(std::fstream& fp, - const e_config_protocol_type& sram_orgz_type, + const e_config_protocol_type& config_protocol_type, const bool& fast_configuration, + const CircuitLibrary& circuit_lib, + const std::vector& global_ports, const ModuleManager& module_manager, const ModuleId& top_module, const BitstreamManager& bitstream_manager, const FabricBitstream& fabric_bitstream) { + /* Try to find global reset/set ports for programming */ + std::vector global_prog_reset_ports; + std::vector global_prog_set_ports; + for (const CircuitPortId& global_port : global_ports) { + VTR_ASSERT(true == circuit_lib.port_is_global(global_port)); + VTR_ASSERT( (false == circuit_lib.port_is_reset(global_port)) + || (false == circuit_lib.port_is_reset(global_port))); + if (true == circuit_lib.port_is_reset(global_port)) { + global_prog_reset_ports.push_back(global_port); + } + if (true == circuit_lib.port_is_set(global_port)) { + global_prog_set_ports.push_back(global_port); + } + } + + bool apply_fast_configuration = fast_configuration; + if ( (global_prog_set_ports.empty() && global_prog_reset_ports.empty()) + && (true == fast_configuration)) { + VTR_LOG_WARN("None of global reset and set ports are defined for programming purpose. Fast configuration is turned off"); + } + bool bit_value_to_skip = find_bit_value_to_skip_for_fast_configuration(config_protocol_type, + apply_fast_configuration, + global_prog_reset_ports, + global_prog_set_ports, + bitstream_manager, fabric_bitstream); + /* Branch on the type of configuration protocol */ - switch (sram_orgz_type) { + switch (config_protocol_type) { case CONFIG_MEM_STANDALONE: print_verilog_top_testbench_vanilla_bitstream(fp, module_manager, top_module, bitstream_manager, fabric_bitstream); break; case CONFIG_MEM_SCAN_CHAIN: - print_verilog_top_testbench_configuration_chain_bitstream(fp, fast_configuration, + print_verilog_top_testbench_configuration_chain_bitstream(fp, apply_fast_configuration, + bit_value_to_skip, bitstream_manager, fabric_bitstream); break; case CONFIG_MEM_MEMORY_BANK: - print_verilog_top_testbench_memory_bank_bitstream(fp, fast_configuration, + print_verilog_top_testbench_memory_bank_bitstream(fp, apply_fast_configuration, + bit_value_to_skip, module_manager, top_module, fabric_bitstream); break; case CONFIG_MEM_FRAME_BASED: - print_verilog_top_testbench_frame_decoder_bitstream(fp, fast_configuration, + print_verilog_top_testbench_frame_decoder_bitstream(fp, apply_fast_configuration, + bit_value_to_skip, module_manager, top_module, fabric_bitstream); break; @@ -1572,6 +1690,7 @@ void print_verilog_top_testbench(const ModuleManager& module_manager, /* load bitstream to FPGA fabric in a configuration phase */ print_verilog_top_testbench_bitstream(fp, config_protocol.type(), fast_configuration, + circuit_lib, global_ports, module_manager, top_module, bitstream_manager, fabric_bitstream);