diff --git a/core/libs/prx/libSceAgc/Acb/src/Memory.cpp b/core/libs/prx/libSceAgc/Acb/src/Memory.cpp
index 17df9c863..c2b181de8 100644
--- a/core/libs/prx/libSceAgc/Acb/src/Memory.cpp
+++ b/core/libs/prx/libSceAgc/Acb/src/Memory.cpp
@@ -31,8 +31,7 @@ std::uint32_t* APS5_VABI sceAgcAcbDmaData(CommandBuffer* buf, std::uint8_t dst,
 }
 
 std::uint32_t APS5_VABI sceAgcAcbDmaDataGetSize() {
-    NotImplemented_nid_no_patch(__func__);
-    return 0;
+    return 28;
 }
 
 std::uint32_t* APS5_VABI sceAgcAcbAtomicMem(CommandBuffer* buf, std::uint8_t atomicOp, std::uint8_t command, std::uint8_t cachePolicy, const volatile void* address, std::uint64_t srcData, std::uint64_t compareData, std::uint16_t loopInterval) {
diff --git a/core/libs/prx/libSceAgc/CMakeLists.txt b/core/libs/prx/libSceAgc/CMakeLists.txt
index ed4ed41a3..d58fe5d6a 100644
--- a/core/libs/prx/libSceAgc/CMakeLists.txt
+++ b/core/libs/prx/libSceAgc/CMakeLists.txt
@@ -113,3 +113,22 @@ if(BUILD_TESTING)
             "PATH=path_list_prepend:$<TARGET_FILE_DIR:libc>")
     endif()
 endif()
+
+add_test_executable(agc_dma_data_tests EXCLUDE_FROM_ALL
+        tests/DmaData.cpp
+        Command/src/Packet.cpp
+        Command/src/Memory.cpp
+        Acb/src/Memory.cpp
+        DcbFlow/src/Memory.cpp
+)
+target_include_directories(agc_dma_data_tests PRIVATE ${LIBS_INCLUDE_DIR})
+target_link_libraries(agc_dma_data_tests PRIVATE libc)
+configure_windows_unwind(agc_dma_data_tests)
+if(BUILD_TESTING)
+    set_target_properties(agc_dma_data_tests PROPERTIES EXCLUDE_FROM_ALL FALSE)
+    add_test(NAME agc_dma_data_tests COMMAND agc_dma_data_tests)
+    if(WIN32)
+        set_tests_properties(agc_dma_data_tests PROPERTIES ENVIRONMENT_MODIFICATION
+            "PATH=path_list_prepend:$<TARGET_FILE_DIR:libc>")
+    endif()
+endif()
diff --git a/core/libs/prx/libSceAgc/tests/DmaData.cpp b/core/libs/prx/libSceAgc/tests/DmaData.cpp
new file mode 100644
index 000000000..77c80988f
--- /dev/null
+++ b/core/libs/prx/libSceAgc/tests/DmaData.cpp
@@ -0,0 +1,94 @@
+#include "prx/libSceAgc/Command/include/Packet.hpp"
+
+#include <algorithm>
+#include <array>
+#include <cstddef>
+#include <cstdint>
+#include <cstdio>
+#include <stdexcept>
+
+extern "C" {
+std::uint32_t* APS5_VABI sceAgcAcbDmaData(CommandBuffer*, std::uint8_t, std::uint8_t, std::uint64_t, std::uint8_t, std::uint8_t, std::uint64_t, std::uint32_t, std::uint8_t, std::uint8_t);
+std::uint32_t APS5_VABI sceAgcAcbDmaDataGetSize();
+std::uint32_t* APS5_VABI sceAgcDcbDmaData(CommandBuffer*, std::uint8_t, std::uint8_t, std::uint8_t, std::uint64_t, std::uint8_t, std::uint8_t, std::uint64_t, std::uint32_t, std::uint8_t, std::uint8_t, std::uint8_t);
+std::uint32_t APS5_VABI sceAgcDcbDmaDataGetSize();
+}
+
+namespace {
+
+constexpr std::uint32_t Sentinel = 0xabcdef01u;
+constexpr std::uint64_t Destination = 0x0000778899aabbccull;
+constexpr std::uint64_t Source = 0x0000112233445566ull;
+
+void check(bool condition, const char* message) {
+    if (!condition) throw std::runtime_error(message);
+}
+
+template <typename TAction>
+void expectFailure(TAction action) {
+    try {
+        action();
+    } catch (const std::runtime_error&) {
+        return;
+    }
+    throw std::runtime_error("expected invalid input to fail");
+}
+
+struct Storage {
+    std::array<std::uint32_t, 16> words{};
+    CommandBuffer buffer{words.data(), words.data() + words.size(), words.data(), words.data() + words.size(), nullptr, nullptr, 0};
+
+    Storage() {
+        words.fill(Sentinel);
+    }
+
+    void limitTo(std::uint32_t count) {
+        buffer.cursor_down = buffer.cursor_up + count;
+    }
+};
+
+std::uint32_t* writeCompute(CommandBuffer* buffer) {
+    return sceAgcAcbDmaData(buffer, 5, 2, Destination, 10, 1, Source, 0x1234u, 1, 1);
+}
+
+std::uint32_t* writeDraw(CommandBuffer* buffer) {
+    return sceAgcDcbDmaData(buffer, 1, 5, 2, Destination, 10, 1, Source, 0x1234u, 1, 1, 1);
+}
+
+template <typename TWriter, typename TSize>
+void testCommand(TWriter writer, TSize size, std::uint32_t control) {
+    const std::array expected{0xc0055000u, control, 0x33445566u, 0x1122u, 0x99aabbccu, 0x7788u, 0xd8001234u};
+    const auto count = static_cast<std::uint32_t>(expected.size());
+    check(size() == count * sizeof(std::uint32_t), "size query does not match the DMA packet");
+
+    Storage storage;
+    auto* packet = writer(&storage.buffer);
+    check(packet == storage.words.data() && std::equal(expected.begin(), expected.end(), packet), "incorrect DMA packet");
+    check(storage.buffer.cursor_up == packet + size() / sizeof(std::uint32_t), "cursor advance does not match the size query");
+    check(std::all_of(storage.words.begin() + count, storage.words.end(), [](std::uint32_t word) { return word == Sentinel; }), "DMA command overwrote following words");
+
+    Storage exact;
+    exact.limitTo(size() / sizeof(std::uint32_t));
+    check(writer(&exact.buffer) == exact.words.data() && exact.buffer.cursor_up == exact.buffer.cursor_down, "DMA packet does not fill the queried size");
+
+    Storage shortBuffer;
+    shortBuffer.limitTo(size() / sizeof(std::uint32_t) - 1u);
+    const auto before = shortBuffer.words;
+    expectFailure([&] { writer(&shortBuffer.buffer); });
+    check(shortBuffer.words == before && shortBuffer.buffer.cursor_up == shortBuffer.words.data(), "failed DMA write modified the buffer");
+}
+
+}
+
+int main() {
+    try {
+        testCommand(writeCompute, sceAgcAcbDmaDataGetSize, 0x44102000u);
+        testCommand(writeDraw, sceAgcDcbDmaDataGetSize, 0xc4102001u);
+        check(sceAgcAcbDmaDataGetSize() == sceAgcDcbDmaDataGetSize(), "compute and draw DMA sizes differ");
+        std::puts("AGC DMA data tests passed");
+        return 0;
+    } catch (const std::exception& error) {
+        std::fprintf(stderr, "%s\n", error.what());
+        return 1;
+    }
+}