Merge pull request #11480 from Pokechu22/dsp-code-alignment

DSPLLE: Add assertion for bad DMA alignment

Source/Core/Core/HW/DSPLLE/DSPHost.cpp

@@ -5,6 +5,7 @@
 
 #include <string>
 
+#include "Common/Assert.h"
 #include "Common/CommonTypes.h"
 #include "Common/Hash.h"
 #include "Common/Logging/Log.h"
@@ -40,13 +41,20 @@ void WriteHostMemory(u8 value, u32 addr)
 
 void DMAToDSP(u16* dst, u32 addr, u32 size)
 {
+  // Hardware testing indicates that a misaligned DMA address does not work properly (it's unclear
+  // exactly what goes wrong currently). A size that's not a multiple of 32 is allowed, though
+  // (and occurs with modern libogc homebrew uCode, including the oggpalyer (asnd uCode) and
+  // modplay (aesnd uCode) examples). It's untested whether extra bytes are copied in that case.
+  ASSERT_MSG(DSPLLE, (addr & 0x1f) == 0, "DSP DMA addr must be 32-byte aligned (was {:08x})", addr);
   auto& system = Core::System::GetInstance();
   auto& memory = system.GetMemory();
   memory.CopyFromEmuSwapped(dst, addr, size);
 }
 
 void DMAFromDSP(const u16* src, u32 addr, u32 size)
 {
+  // See comment in DMAToDSP
+  ASSERT_MSG(DSPLLE, (addr & 0x1f) == 0, "DSP DMA addr must be 32-byte aligned (was {:08x})", addr);
   auto& system = Core::System::GetInstance();
   auto& memory = system.GetMemory();
   memory.CopyToEmuSwapped(addr, src, size);

Source/DSPTool/DSPTool.cpp

@@ -68,7 +68,7 @@ static std::string CodeToHeader(const std::vector<u16>& code, const std::string&
   SplitPath(filename, nullptr, &filename_without_extension, nullptr);
   header.append(fmt::format("const char* UCODE_NAMES[NUM_UCODES] = {{\"{}\"}};\n\n",
                             filename_without_extension));
-  header.append("const unsigned short dsp_code[NUM_UCODES][0x1000] = {\n");
+  header.append("alignas(0x20) const unsigned short dsp_code[NUM_UCODES][0x1000] = {\n");
 
   header.append("\t{\n\t\t");
   for (u32 j = 0; j < code_padded.size(); j++)