diff --git a/xmrstak/backend/amd/amd_gpu/gpu.cpp b/xmrstak/backend/amd/amd_gpu/gpu.cpp index 1e6abc990..7d9484999 100644 --- a/xmrstak/backend/amd/amd_gpu/gpu.cpp +++ b/xmrstak/backend/amd/amd_gpu/gpu.cpp @@ -865,6 +865,8 @@ size_t InitOpenCLGpu(cl_context opencl_ctx, GpuContext* ctx, const char* source_ rx_conf = &RandomX_WowneroConfig; else if(miner_algo == randomX) rx_conf = &RandomX_MoneroConfig; + else if(miner_algo == randomX_arqma) + rx_conf = &RandomX_ArqmaConfig; const uint32_t rx_parameters = (PowerOf2(rx_conf->ScratchpadL1_Size) << 0) | @@ -1189,6 +1191,9 @@ size_t InitOpenCL(GpuContext* ctx, size_t num_gpus, size_t platform_idx) const char* randomx_constants_monero_h = #include "./opencl/RandomX/randomx_constants_monero.h" ; + const char* randomx_constants_arqma_h = + #include "./opencl/RandomX/randomx_constants_arqma.h" + ; const char* aesCL = #include "./opencl/RandomX/aes.cl" ; @@ -1214,6 +1219,8 @@ size_t InitOpenCL(GpuContext* ctx, size_t num_gpus, size_t platform_idx) source_code.append(randomx_constants_loki_h); else if(user_algo == randomX) source_code.append(randomx_constants_monero_h); + else if(user_algo == randomX_arqma) + source_code.append(randomx_constants_arqma_h); source_code.append(std::regex_replace(aesCL, std::regex("#include \"fillAes1Rx4.cl\""), fillAes1Rx4CL)); source_code.append(std::regex_replace(blake2bCL, std::regex("#include \"blake2b_double_block.cl\""), blake2b_double_blockCL)); diff --git a/xmrstak/backend/amd/amd_gpu/opencl/RandomX/randomx_constants_arqma.h b/xmrstak/backend/amd/amd_gpu/opencl/RandomX/randomx_constants_arqma.h new file mode 100644 index 000000000..deeddc2b9 --- /dev/null +++ b/xmrstak/backend/amd/amd_gpu/opencl/RandomX/randomx_constants_arqma.h @@ -0,0 +1,99 @@ +R"===( +/* +Copyright (c) 2019 SChernykh + +This file is part of RandomX OpenCL. + +RandomX OpenCL 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 3 of the License, or +(at your option) any later version. + +RandomX OpenCL 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 RandomX OpenCL. If not, see . +*/ + +//Dataset base size in bytes. Must be a power of 2. +#define RANDOMX_DATASET_BASE_SIZE 2147483648 + +//Dataset extra size. Must be divisible by 64. +#define RANDOMX_DATASET_EXTRA_SIZE 33554368 + +//Scratchpad L3 size in bytes. Must be a power of 2. +#define RANDOMX_SCRATCHPAD_L3 262144 + +//Scratchpad L2 size in bytes. Must be a power of two and less than or equal to RANDOMX_SCRATCHPAD_L3. +#define RANDOMX_SCRATCHPAD_L2 131072 + +//Scratchpad L1 size in bytes. Must be a power of two (minimum 64) and less than or equal to RANDOMX_SCRATCHPAD_L2. +#define RANDOMX_SCRATCHPAD_L1 16384 + +//Jump condition mask size in bits. +#define RANDOMX_JUMP_BITS 8 + +//Jump condition mask offset in bits. The sum of RANDOMX_JUMP_BITS and RANDOMX_JUMP_OFFSET must not exceed 16. +#define RANDOMX_JUMP_OFFSET 8 + +//Integer instructions +#define RANDOMX_FREQ_IADD_RS 16 +#define RANDOMX_FREQ_IADD_M 7 +#define RANDOMX_FREQ_ISUB_R 16 +#define RANDOMX_FREQ_ISUB_M 7 +#define RANDOMX_FREQ_IMUL_R 16 +#define RANDOMX_FREQ_IMUL_M 4 +#define RANDOMX_FREQ_IMULH_R 4 +#define RANDOMX_FREQ_IMULH_M 1 +#define RANDOMX_FREQ_ISMULH_R 4 +#define RANDOMX_FREQ_ISMULH_M 1 +#define RANDOMX_FREQ_IMUL_RCP 8 +#define RANDOMX_FREQ_INEG_R 2 +#define RANDOMX_FREQ_IXOR_R 15 +#define RANDOMX_FREQ_IXOR_M 5 +#define RANDOMX_FREQ_IROR_R 8 +#define RANDOMX_FREQ_IROL_R 2 +#define RANDOMX_FREQ_ISWAP_R 4 + +//Floating point instructions +#define RANDOMX_FREQ_FSWAP_R 4 +#define RANDOMX_FREQ_FADD_R 16 +#define RANDOMX_FREQ_FADD_M 5 +#define RANDOMX_FREQ_FSUB_R 16 +#define RANDOMX_FREQ_FSUB_M 5 +#define RANDOMX_FREQ_FSCAL_R 6 +#define RANDOMX_FREQ_FMUL_R 32 +#define RANDOMX_FREQ_FDIV_M 4 +#define RANDOMX_FREQ_FSQRT_R 6 + +//Control instructions +#define RANDOMX_FREQ_CBRANCH 25 +#define RANDOMX_FREQ_CFROUND 1 + +//Store instruction +#define RANDOMX_FREQ_ISTORE 16 + +//No-op instruction +#define RANDOMX_FREQ_NOP 0 + +#define RANDOMX_DATASET_ITEM_SIZE 64 + +#define RANDOMX_PROGRAM_SIZE 256 + +#define HASH_SIZE 64 +#define ENTROPY_SIZE (128 + RANDOMX_PROGRAM_SIZE * 8) +#define REGISTERS_SIZE 256 +#define IMM_BUF_SIZE (RANDOMX_PROGRAM_SIZE * 4 - REGISTERS_SIZE) +#define IMM_INDEX_COUNT ((IMM_BUF_SIZE / 4) - 2) +#define VM_STATE_SIZE (REGISTERS_SIZE + IMM_BUF_SIZE + RANDOMX_PROGRAM_SIZE * 4) +#define ROUNDING_MODE (RANDOMX_FREQ_CFROUND ? -1 : 0) + +// Scratchpad L1/L2/L3 bits +#define LOC_L1 (32 - 14) +#define LOC_L2 (32 - 17) +#define LOC_L3 (32 - 18) +)===" + \ No newline at end of file diff --git a/xmrstak/backend/cpu/crypto/cryptonight_aesni.h b/xmrstak/backend/cpu/crypto/cryptonight_aesni.h index b6e285b0b..984b2c502 100644 --- a/xmrstak/backend/cpu/crypto/cryptonight_aesni.h +++ b/xmrstak/backend/cpu/crypto/cryptonight_aesni.h @@ -186,6 +186,8 @@ struct RandomX_generator randomx_apply_config(RandomX_LokiConfig); else if(ALGO == randomX_wow) randomx_apply_config(RandomX_WowneroConfig); + else if(ALGO == randomX_arqma) + randomx_apply_config(RandomX_ArqmaConfig); } for(size_t i = 0; i < N; i++) diff --git a/xmrstak/backend/cpu/minethd.cpp b/xmrstak/backend/cpu/minethd.cpp index 8cf72c51d..5773d472d 100644 --- a/xmrstak/backend/cpu/minethd.cpp +++ b/xmrstak/backend/cpu/minethd.cpp @@ -323,6 +323,18 @@ bool minethd::self_test() ctx[0]->hash_fn("\x54\x68\x69\x73\x20\x69\x73\x20\x61\x20\x74\x65\x73\x74\x20\x54\x68\x69\x73\x20\x69\x73\x20\x61\x20\x74\x65\x73\x74\x20\x54\x68\x69\x73\x20\x69\x73\x20\x61\x20\x74\x65\x73\x74", 44, out, ctx, algo); bResult = bResult && memcmp(out, "\xc7\x78\x25\x35\xd8\x11\xda\x56\x32\xb0\xa4\xb8\x9d\x9d\x1a\xdf\x7b\x9\x69\xae\x92\x4f\xd4\xd0\x4c\x6b\x55\x5e\x77\xe9\x8f\x38", 32) == 0; } + else if(algo == POW(randomX_arqma)) + { + printer::inst()->print_msg(L0, "start self test for 'randomx_arqma' (can be disabled with the command line option '--noTest')"); + minethd::cn_on_new_job set_job; + func_multi_selector<1>(ctx, set_job, ::jconf::inst()->HaveHardwareAes(), algo); + miner_work work; + work.iBlockHeight = 1806260; + work.seed_hash[0] = 1; + set_job(work, ctx); + ctx[0]->hash_fn("\x54\x68\x69\x73\x20\x69\x73\x20\x61\x20\x74\x65\x73\x74\x20\x54\x68\x69\x73\x20\x69\x73\x20\x61\x20\x74\x65\x73\x74\x20\x54\x68\x69\x73\x20\x69\x73\x20\x61\x20\x74\x65\x73\x74", 44, out, ctx, algo); + bResult = bResult && memcmp(out, "\x96\xd5\x33\x16\x7f\x33\xeb\x37\xc7\xc5\x44\xae\xc8\x55\x96\x62\x09\x59\xc1\xfe\xb8\xca\x5c\x40\x37\x06\x07\x64\x60\xab\x86\xec", 32) == 0; + } else { printer::inst()->print_msg(L0, @@ -446,6 +458,9 @@ void minethd::func_multi_selector(cryptonight_ctx** ctx, minethd::cn_on_new_job& case randomX_wow: algv = 2; break; + case randomX_arqma: + algv = 3; + break; default: algv = 0; break; @@ -462,7 +477,11 @@ void minethd::func_multi_selector(cryptonight_ctx** ctx, minethd::cn_on_new_job& //wow RandomX_hash::template hash, - RandomX_hash::template hash + RandomX_hash::template hash, + + //arqma + RandomX_hash::template hash, + RandomX_hash::template hash }; std::bitset<1> digit; @@ -476,7 +495,8 @@ void minethd::func_multi_selector(cryptonight_ctx** ctx, minethd::cn_on_new_job& static const std::unordered_map on_new_job_map = { {randomX, RandomX_generator::template cn_on_new_job}, {randomX_loki, RandomX_generator::template cn_on_new_job}, - {randomX_wow, RandomX_generator::template cn_on_new_job} + {randomX_wow, RandomX_generator::template cn_on_new_job}, + {randomX_arqma, RandomX_generator::template cn_on_new_job} }; auto it = on_new_job_map.find(algo.Id()); @@ -666,7 +686,7 @@ void minethd::multiway_work_main() for(size_t i = 0; i < N; i++) current_nonces[i] = iNonce - N + i; - + if((iCount++ % update_stat_each) == 0) //Store stats every 8*N hashes { updateStats((iCount - iLastCount) * N, oWork.iPoolId); diff --git a/xmrstak/backend/cryptonight.hpp b/xmrstak/backend/cryptonight.hpp index 7ee76de7a..0559601aa 100644 --- a/xmrstak/backend/cryptonight.hpp +++ b/xmrstak/backend/cryptonight.hpp @@ -13,6 +13,7 @@ enum xmrstak_algo_id randomX = 1, randomX_loki = 2, randomX_wow = 3, + randomX_arqma = 4 //cryptonight_turtle = start_derived_algo_id, // please add the algorithm name to get_algo_name() @@ -24,12 +25,13 @@ enum xmrstak_algo_id */ inline std::string get_algo_name(xmrstak_algo_id algo_id) { - static std::array base_algo_names = + static std::array base_algo_names = {{ "invalid_algo", "randomx", "randomx_loki", - "randomx_wow" + "randomx_wow", + "randomx_arqma" }}; static std::array derived_algo_names = @@ -156,25 +158,15 @@ constexpr size_t CN_MEMORY = 2 * 1024 * 1024; constexpr uint32_t CN_ITER = 0x80000; constexpr uint32_t CN_MASK = ((CN_MEMORY - 1) / 16) * 16; -// crptonight gpu -constexpr uint32_t CN_GPU_MASK = 0x1FFFC0; -constexpr uint32_t CN_GPU_ITER = 0xC000; - -// cryptonight turtle (the mask is not using the full 256kib scratchpad) -constexpr uint32_t CN_TURTLE_MASK = 0x1FFF0; - -constexpr uint32_t CN_ZELERIUS_ITER = 0x60000; - -constexpr uint32_t CN_WALTZ_ITER = 0x60000; - -constexpr uint32_t CN_DOUBLE_ITER = 0x100000; +constexpr uint32_t RX_ARQMA_ITER = 0x10000; inline xmrstak_algo POW(xmrstak_algo_id algo_id) { - static std::array pow = {{{invalid_algo, invalid_algo}, + static std::array pow = {{{invalid_algo, invalid_algo}, {randomX, randomX, CN_ITER, CN_MEMORY}, {randomX_loki, randomX_loki, CN_ITER, CN_MEMORY}, - {randomX_wow, randomX_wow, CN_ITER, CN_MEMORY/2} + {randomX_wow, randomX_wow, CN_ITER, CN_MEMORY/2}, + {randomX_arqma, randomX_arqma, RX_ARQMA_ITER, CN_MEMORY/8} }}; return pow[algo_id]; diff --git a/xmrstak/backend/nvidia/RandomX_Arqma/configuration.h b/xmrstak/backend/nvidia/RandomX_Arqma/configuration.h new file mode 100644 index 000000000..1c4dec2db --- /dev/null +++ b/xmrstak/backend/nvidia/RandomX_Arqma/configuration.h @@ -0,0 +1,126 @@ +/* +Copyright (c) 2018-2019, tevador +Copyright (c) 2019, Wownero Inc., a Monero Enterprise Alliance partner company + +All rights reserved. + +Redistribution and use in source and binary forms, with or without +modification, are permitted provided that the following conditions are met: + * Redistributions of source code must retain the above copyright + notice, this list of conditions and the following disclaimer. + * Redistributions in binary form must reproduce the above copyright + notice, this list of conditions and the following disclaimer in the + documentation and/or other materials provided with the distribution. + * Neither the name of the copyright holder nor the + names of its contributors may be used to endorse or promote products + derived from this software without specific prior written permission. + +THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND +ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED +WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE +DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE +FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR +SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER +CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, +OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +*/ + +#pragma once + +//Cache size in KiB. Must be a power of 2. +#define RANDOMX_ARGON_MEMORY 262144 + +//Number of Argon2d iterations for Cache initialization. +#define RANDOMX_ARGON_ITERATIONS 1 + +//Number of parallel lanes for Cache initialization. +#define RANDOMX_ARGON_LANES 1 + +//Argon2d salt +#define RANDOMX_ARGON_SALT "RandomARQ\x01" + +//Number of random Cache accesses per Dataset item. Minimum is 2. +#define RANDOMX_CACHE_ACCESSES 8 + +//Target latency for SuperscalarHash (in cycles of the reference CPU). +#define RANDOMX_SUPERSCALAR_LATENCY 170 + +//Dataset base size in bytes. Must be a power of 2. +#define RANDOMX_DATASET_BASE_SIZE 2147483648 + +//Dataset extra size. Must be divisible by 64. +#define RANDOMX_DATASET_EXTRA_SIZE 33554368 + +//Number of instructions in a RandomX program. Must be divisible by 8. +#define RANDOMX_PROGRAM_SIZE 256 + +//Number of iterations during VM execution. +#define RANDOMX_PROGRAM_ITERATIONS 1024 + +//Number of chained VM executions per hash. +#define RANDOMX_PROGRAM_COUNT 4 + +//Scratchpad L3 size in bytes. Must be a power of 2. +#define RANDOMX_SCRATCHPAD_L3 262144 + +//Scratchpad L2 size in bytes. Must be a power of two and less than or equal to RANDOMX_SCRATCHPAD_L3. +#define RANDOMX_SCRATCHPAD_L2 131072 + +//Scratchpad L1 size in bytes. Must be a power of two (minimum 64) and less than or equal to RANDOMX_SCRATCHPAD_L2. +#define RANDOMX_SCRATCHPAD_L1 16384 + +//Jump condition mask size in bits. +#define RANDOMX_JUMP_BITS 8 + +//Jump condition mask offset in bits. The sum of RANDOMX_JUMP_BITS and RANDOMX_JUMP_OFFSET must not exceed 16. +#define RANDOMX_JUMP_OFFSET 8 + +/* +Instruction frequencies (per 256 opcodes) +Total sum of frequencies must be 256 +*/ + +//Integer instructions +#define RANDOMX_FREQ_IADD_RS 16 +#define RANDOMX_FREQ_IADD_M 7 +#define RANDOMX_FREQ_ISUB_R 16 +#define RANDOMX_FREQ_ISUB_M 7 +#define RANDOMX_FREQ_IMUL_R 16 +#define RANDOMX_FREQ_IMUL_M 4 +#define RANDOMX_FREQ_IMULH_R 4 +#define RANDOMX_FREQ_IMULH_M 1 +#define RANDOMX_FREQ_ISMULH_R 4 +#define RANDOMX_FREQ_ISMULH_M 1 +#define RANDOMX_FREQ_IMUL_RCP 8 +#define RANDOMX_FREQ_INEG_R 2 +#define RANDOMX_FREQ_IXOR_R 15 +#define RANDOMX_FREQ_IXOR_M 5 +#define RANDOMX_FREQ_IROR_R 8 +#define RANDOMX_FREQ_IROL_R 2 +#define RANDOMX_FREQ_ISWAP_R 4 + +//Floating point instructions +#define RANDOMX_FREQ_FSWAP_R 4 +#define RANDOMX_FREQ_FADD_R 16 +#define RANDOMX_FREQ_FADD_M 5 +#define RANDOMX_FREQ_FSUB_R 16 +#define RANDOMX_FREQ_FSUB_M 5 +#define RANDOMX_FREQ_FSCAL_R 6 +#define RANDOMX_FREQ_FMUL_R 32 +#define RANDOMX_FREQ_FDIV_M 4 +#define RANDOMX_FREQ_FSQRT_R 6 + +//Control instructions +#define RANDOMX_FREQ_CBRANCH 25 +#define RANDOMX_FREQ_CFROUND 1 + +//Store instruction +#define RANDOMX_FREQ_ISTORE 16 + +//No-op instruction +#define RANDOMX_FREQ_NOP 0 +/* ------ + 256 +*/ diff --git a/xmrstak/backend/nvidia/RandomX_Arqma/randomx_arqma.cu b/xmrstak/backend/nvidia/RandomX_Arqma/randomx_arqma.cu new file mode 100644 index 000000000..3a248e27c --- /dev/null +++ b/xmrstak/backend/nvidia/RandomX_Arqma/randomx_arqma.cu @@ -0,0 +1,33 @@ +/* +Copyright (c) 2019 SChernykh + +This file is part of RandomX CUDA. + +RandomX CUDA 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 3 of the License, or +(at your option) any later version. + +RandomX CUDA 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 RandomX CUDA. If not, see. +*/ + +#include +#include +#include +#include +#include +//#include "xmrstak/backend/cpu/crypto/randomx/randomx.h" +#include "xmrstak/backend/nvidia/nvcc_code/cryptonight.hpp" +#include "../nvcc_code/cuda_device.hpp" + +namespace RandomX_Arqma { + #include "configuration.h" + #define fillAes4Rx4 fillAes4Rx4_v104 + #include "../RandomX/common.hpp" +} diff --git a/xmrstak/backend/nvidia/minethd.cpp b/xmrstak/backend/nvidia/minethd.cpp index d762d1851..f585c9933 100644 --- a/xmrstak/backend/nvidia/minethd.cpp +++ b/xmrstak/backend/nvidia/minethd.cpp @@ -294,6 +294,10 @@ void minethd::work_main() { RandomX_Loki::hash(&ctx, iNonce, oWork.iTarget, &foundCount, foundNonce, h_per_round); } + else if(miner_algo == randomX_arqma) + { + RandomX_Arqma::hash(&ctx, iNonce, oWork.iTarget, &foundCount, foundNonce, h_per_round); + } diff --git a/xmrstak/backend/nvidia/nvcc_code/cryptonight.hpp b/xmrstak/backend/nvidia/nvcc_code/cryptonight.hpp index 9729d6800..985054310 100644 --- a/xmrstak/backend/nvidia/nvcc_code/cryptonight.hpp +++ b/xmrstak/backend/nvidia/nvcc_code/cryptonight.hpp @@ -63,4 +63,5 @@ void randomx_prepare(nvid_ctx *ctx, const uint8_t* seed_hash, const xmrstak_algo namespace RandomX_Monero { void hash(nvid_ctx *ctx, uint32_t nonce, uint64_t target, uint32_t *rescount, uint32_t *resnonce, uint32_t batch_size); } namespace RandomX_Wownero { void hash(nvid_ctx *ctx, uint32_t nonce, uint64_t target, uint32_t *rescount, uint32_t *resnonce, uint32_t batch_size); } namespace RandomX_Loki { void hash(nvid_ctx *ctx, uint32_t nonce, uint64_t target, uint32_t *rescount, uint32_t *resnonce, uint32_t batch_size); } +namespace RandomX_Arqma { void hash(nvid_ctx *ctx, uint32_t nonce, uint64_t target, uint32_t *rescount, uint32_t *resnonce, uint32_t batch_size); } diff --git a/xmrstak/jconf.cpp b/xmrstak/jconf.cpp index 43ec81702..c4ef358fb 100644 --- a/xmrstak/jconf.cpp +++ b/xmrstak/jconf.cpp @@ -101,9 +101,11 @@ constexpr size_t iConfigCnt = (sizeof(oConfigValues) / sizeof(oConfigValues[0])) xmrstak::coin_selection coins[] = { // name, userpool, default_pool_suggestion + {"arqma", {POW(randomX_arqma)}, {POW(randomX_arqma)}, nullptr}, {"loki", {POW(randomX_loki)}, {POW(randomX_loki)}, nullptr}, {"monero", {POW(randomX)}, {POW(randomX)}, nullptr}, {"randomx", {POW(randomX)}, {POW(randomX)}, nullptr}, + {"randomx_arqma", {POW(randomX_arqma)}, {POW(randomX_arqma)}, nullptr}, {"randomx_loki", {POW(randomX_loki)}, {POW(randomX_loki)}, nullptr}, {"randomx_wow", {POW(randomX_wow)}, {POW(randomX_wow)}, nullptr}, {"wownero", {POW(randomX_wow)}, {POW(randomX_wow)}, nullptr} diff --git a/xmrstak/pools.tpl b/xmrstak/pools.tpl index d28cddd7a..1f60ea262 100644 --- a/xmrstak/pools.tpl +++ b/xmrstak/pools.tpl @@ -25,6 +25,8 @@ POOLCONF], * * Native algorithms which do not depend on any block versions: * + * # 256KiB scratchpad memory + * randomx_arqma * # 1MiB scratchpad memory * randomx_wow * # 2MiB scratchpad memory