Move dead submodules in-tree

Signed-off-by: swurl <swurl@swurl.xyz>

1 files changed, 135 insertions, 0 deletions

diff --git a/externals/libadrenotools/src/bcenabler.cpp b/externals/libadrenotools/src/bcenabler.cpp
new file mode 100644
index 0000000000..1deb41df40
--- /dev/null
+++ b/externals/libadrenotools/src/bcenabler.cpp
@@ -0,0 +1,135 @@
+// SPDX-License-Identifier: BSD-2-Clause
+// Copyright © 2021 Billy Laws
+
+#include <fstream>
+#include <string>
+#include <cstring>
+#include <sys/mman.h>
+#include <unistd.h>
+#include <adrenotools/bcenabler.h>
+#include "gen/bcenabler_patch.h"
+
+enum adrenotools_bcn_type adrenotools_get_bcn_type(uint32_t major, uint32_t minor, uint32_t vendorId) {
+    if (vendorId != 0x5143 || major != 512)
+        return ADRENOTOOLS_BCN_INCOMPATIBLE;
+
+    if (minor >= 514)
+        return ADRENOTOOLS_BCN_BLOB;
+
+    return ADRENOTOOLS_BCN_PATCH;
+}
+
+// Searches /proc/self/maps for the first free page after the given address
+static void *find_free_page(uintptr_t address) {
+    std::ifstream procMaps("/proc/self/maps");
+
+    uintptr_t end{};
+
+    for (std::string line; std::getline(procMaps, line); ) {
+        std::size_t addressSeparator{line.find('-')};
+        uintptr_t start{std::strtoull(line.substr(0, addressSeparator).c_str(), nullptr, 16)};
+
+        if (end > address && start != end)
+            return reinterpret_cast<void *>(end);
+
+        end = std::strtoull(line.substr(addressSeparator + 1, line.find( ' ')).c_str(), nullptr, 16);
+    }
+
+    return nullptr;
+}
+
+static void *align_ptr(void *ptr) {
+    return reinterpret_cast<void *>(reinterpret_cast<uintptr_t>(ptr) & ~(getpagesize() - 1));
+}
+
+bool adrenotools_patch_bcn(void *vkGetPhysicalDeviceFormatPropertiesFn) {
+    union Branch {
+        struct {
+            int32_t offset : 26; //!< 26-bit branch offset
+            uint8_t sig : 6;  //!< 6-bit signature (0x25 for linked, 0x5 for jump)
+        };
+
+        uint32_t raw{};
+    };
+    static_assert(sizeof(Branch) == 4, "Branch size is invalid");
+
+    // Find the nearest unmapped page where we can place patch code
+    void *patchPage{find_free_page(reinterpret_cast<uintptr_t>(vkGetPhysicalDeviceFormatPropertiesFn))};
+    if (!patchPage)
+        return false;
+
+    // Map patch region
+    void *ptr{mmap(patchPage, getpagesize(),  PROT_READ | PROT_WRITE | PROT_EXEC, MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED, 0, 0)};
+    if (ptr != patchPage)
+        return false;
+
+    // Allow reading from the blob's .text section since some devices enable ---X
+    // Protect two pages just in case we happen to land on a page boundary
+    if (mprotect(align_ptr(vkGetPhysicalDeviceFormatPropertiesFn), getpagesize() * 2, PROT_WRITE | PROT_READ | PROT_EXEC))
+        return false;
+
+    // First branch in this function is targeted at the function we want to patch
+    Branch *blInst{reinterpret_cast<Branch *>(vkGetPhysicalDeviceFormatPropertiesFn)};
+
+    constexpr uint8_t BranchLinkSignature{0x25};
+
+    // Search for first instruction with the BL signature
+    while (blInst->sig != BranchLinkSignature)
+        blInst++;
+
+    // Internal QGL format conversion function that we need to patch
+    uint32_t *convFormatFn{reinterpret_cast<uint32_t *>(blInst) + blInst->offset};
+
+    // See mprotect call above
+    // This time we also set PROT_WRITE so we can write our patch to the page
+    if (mprotect(align_ptr(convFormatFn), getpagesize() * 2, PROT_WRITE | PROT_READ | PROT_EXEC))
+        return false;
+
+    // This would normally set the default result to 0 (error) in the format not found case
+    constexpr uint32_t ClearResultSignature{0x2a1f03e0};
+
+    // We replace it with a branch to our own extended if statement which adds in the extra things for BCn
+    uint32_t *clearResultPtr{convFormatFn};
+    while (*clearResultPtr != ClearResultSignature)
+        clearResultPtr++;
+
+    // Ensure we don't write out of bounds
+    if (PatchRawData_size > getpagesize())
+        return false;
+
+    // Copy the patch function to our mapped page
+    memcpy(patchPage, PatchRawData, PatchRawData_size);
+
+    // Fixup the patch code so it correctly returns back to the driver after running
+    constexpr uint32_t PatchReturnFixupMagic{0xffffffff};
+    constexpr uint8_t BranchSignature{0x5};
+
+    uint32_t *fixupTargetPtr{clearResultPtr + 1};
+    auto *fixupPtr{reinterpret_cast<uint32_t *>(patchPage)};
+    for (long unsigned int i{}; i < (PatchRawData_size / sizeof(uint32_t)); i++, fixupPtr++) {
+        if (*fixupPtr == PatchReturnFixupMagic) {
+            Branch branchToDriver{
+                {
+                    .offset = static_cast<int32_t>((reinterpret_cast<intptr_t>(fixupTargetPtr) - reinterpret_cast<intptr_t>(fixupPtr)) / sizeof(int32_t)),
+                    .sig = BranchSignature,
+                }
+            };
+
+            *fixupPtr = branchToDriver.raw;
+        }
+    }
+
+    Branch branchToPatch{
+        {
+            .offset = static_cast<int32_t>((reinterpret_cast<intptr_t>(patchPage) - reinterpret_cast<intptr_t>(clearResultPtr)) / sizeof(int32_t)),
+            .sig = BranchSignature,
+        }
+    };
+
+    *clearResultPtr = branchToPatch.raw;
+
+    asm volatile("ISB");
+
+    // Done!
+    return true;
+}