progress: ImGui Port - Desktop UI + ImGui rendering performance overhaul

Full ImGui desktop environment (desktop.pas):
- Gradient wallpaper, taskbar with clock, start menu
- Desktop icons with click-to-open
- Windowed apps: System Info, Terminal, File Browser, Task Manager
- Terminal dispatches to registered kernel commands with output capture

Performance: Software rasterizer rewrite (imgui.pas, imgbridge.c)
- Quad detection: merge consecutive triangle pairs into fast rect fills
- 3 new fast-path rect fillers (solid/gradient/textured) using REP STOSD
  and 16.16 fixed-point integer inner loops
- Triangle rasterizer rewritten with fixed-point edge functions
- Back-buffer clear: DrawPixel loop -> REP STOSD (~200x faster)
- Render stat debug counters added

ISR-safe input buffering (imgbridge.c)
- Keyboard/mouse events buffered in lock-free ring buffers from ISR context
- Drained once per frame from main loop to prevent data races

Other changes:
- imguitypes.pas: InputTextFlags renumbered for cimgui 1.91+
- video.pas: backBufferLocation getter added
- kernel.pas: VFS init moved earlier, main loop uses desktop_frame,
  mouse hook uses ISR-safe buffering
- lmemorymanager.pas: kalloc/kfree exported with public aliases for C linkage
- scheduler.pas: Root_Task moved to interface for desktop task manager
- terminal.pas: freeParams exposed in interface

.drone.yml

@@ -24,7 +24,7 @@ steps:
       - find . -type f -print0 | xargs -0 dos2unix
       - chmod +x /drone/src/*.sh
       - /drone/src/compile.sh
-      
+
   - name: upload-iso-artifact
     image: alpine/git
     depends_on:
@@ -49,18 +49,4 @@ steps:
         -H "Authorization: token $GITEA_TOKEN" || echo "No previous latest version found."
       - |
         curl -X PUT https://gitea.spexeah.com/api/packages/Spexeah/generic/asuro-iso/latest/Asuro.iso \
-        -H "Authorization: token $GITEA_TOKEN" --upload-file "Asuro-$(git rev-parse --short HEAD).iso"
-
-  - name: msg status
-    image: appleboy/drone-discord
-    failure: ignore
-    depends_on:
-      - compile
-    when:
-      status: [success, failure, changed]
-    settings:
-      webhook_id:
-        from_secret: discord_webhook_id
-      webhook_token:
-        from_secret: discord_webhook_secret
-      message: "**Asuro Build**\n\n{{#success build.status}}✅ Build successful!\n\n{{else}}❌ Build failed!\n\n{{/success}}Repository: `{{repo.namespace}}/{{repo.name}}`\nBranch: `{{commit.branch}}`\nCommit: `{{commit.sha}}`\nAuthor: `{{commit.author}} <{{commit.email}}>`\n\nGitea Diff: [Link](<{{commit.link}}>)\nDrone Build: [Link](<{{build.link}}>)\n\nMessage: {{commit.message}}"
+        -H "Authorization: token $GITEA_TOKEN" --upload-file "Asuro-$(git rev-parse --short HEAD).iso"

.gitattributes

@@ -1,8 +1 @@
-* text=auto eol=lf
-lvglh/** linguist-vendored
-lvgl/** linguist-vendored
-.vscode/* linguist-vendored
-lib/* linguist-generated
-release/* linguist-generated
-iso/* linguist-generated
-*.asm linguist-detectable
+* text=auto eol=lf

.gitignore

@@ -11,8 +11,3 @@
 /*.img
 src/include/asuro.pas
 localenv.json
-/lvgl/
-dockerout.txt
-AGENTS.md
-*.log
-/doc/*.md

.mailmap

@@ -1,13 +0,0 @@
-# Map all Aaron identities to a single preferred identity
-Aaron Hance <[email protected]> aaron <aaron@6dbc8c32-bb84-406f-8558-d1cf31a0ab0c>
-Aaron Hance <[email protected]> aaronhance <[email protected]>
-Aaron Hance <[email protected]> aaron hance <[email protected]>
-Aaron Hance <[email protected]> Aaron <[email protected]>
-
-# Map all Kieron identities to a single preferred identity
-Kieron Morris <[email protected]> kieron <kieron@6dbc8c32-bb84-406f-8558-d1cf31a0ab0c>
-Kieron Morris <[email protected]> Kieron <[email protected]>
-Kieron Morris <[email protected]> t3hn3rd <[email protected]>
-
-# Map goose's multiple identities
-goose <goose@6dbc8c32-bb84-406f-8558-d1cf31a0ab0c> goose <[email protected]>

Dockerfile

@@ -5,11 +5,14 @@ VOLUME ["/code"]
 ENV DEBIAN_FRONTEND=noninteractive
 RUN dpkg --add-architecture i386
 RUN apt-get update && apt-get install -y \
-	curl dos2unix wget git make nasm binutils xorriso grub-pc-bin gcc gcc-multilib && \
+	curl dos2unix wget git make nasm binutils xorriso grub-pc-bin \
+	gcc-multilib g++-multilib && \
 	apt-get clean my room
 
+RUN git clone --depth=1 --recurse-submodules https://github.com/cimgui/cimgui.git /cimgui
+
 SHELL ["/bin/bash", "-c"]
-ARG FPC_VERSION=3.2.2
+ARG FPC_VERSION=2.6.4
 RUN curl -sL https://sourceforge.net/projects/freepascal/files/Linux/$FPC_VERSION/fpc-$FPC_VERSION.i386-linux.tar/download | tar -xf - && \
 	pushd fpc-$FPC_VERSION.i386-linux && ./install.sh && popd && \
 	rm -rf fpc-$FPC_VERSION.i386-linux

compile.sh

@@ -7,7 +7,7 @@ echo "Asuro Compilation"
 echo " "
 
 #Compile Stub.asm
-rm -f lib/*
+rm lib/*
 
 runOrFail() {
 	local binary=$1
@@ -23,7 +23,7 @@ runOrFail() {
 declare -a run_steps=(
 	"compile_stub.sh" "Failed to compile stub!"
 	"compile_vergen.sh" "Versions failed to compile"
-	"compile_lvgl.sh" "Failed to compile LVGL!"
+	"compile_imgui.sh" "Failed to compile ImGui!"
 	"compile_sources.sh" "Failed to compile FPC Sources!"
 	"compile_link.sh" "Failed linking!"
 	"compile_isogen.sh" "Failed to create ISO!"

compile_imgui.sh

@@ -0,0 +1,90 @@
+#!/usr/bin/env bash
+echo " "
+echo "======================="
+echo " "
+echo "Compiling ImGui (cimgui)..."
+echo " "
+
+IMGUI_DIR=/cimgui
+IMGUI_SRC=$IMGUI_DIR/imgui
+BRIDGE_SRC=src/driver/video/imgui
+
+# Flags shared by all C/C++ compilation units:
+#   -m32              -> i386 target
+#   -ffreestanding    -> no implicit stdlib inclusion
+#   -fno-builtin      -> don't inline memcpy/memset/etc. so our stubs are used
+#   -O2               -> optimise for speed
+#   -ffunction-sections -fdata-sections -> allow --gc-sections in linker
+C_FLAGS="-m32 -ffreestanding -fno-builtin -O2 -ffunction-sections -fdata-sections"
+
+# Extra flags for C++ translation units (cimgui/imgui sources):
+#   -fno-exceptions         -> no stack-unwinding machinery
+#   -fno-rtti               -> no typeinfo / dynamic_cast
+#   -fno-use-cxa-atexit     -> don't emit __cxa_atexit calls for static dtors
+#   -fno-threadsafe-statics -> no guard-variable emission for local statics
+# NOTE: *not* -ffreestanding / -fno-builtin here — imgui includes <cmath> and
+#       other hosted headers that refuse to compile in freestanding mode.
+#       The object files are archived into a static lib and linked freestanding;
+#       any hosted-stdlib calls (malloc/free/sin/cos/…) resolve to crtshim.c.
+CPP_FLAGS="-m32 -O2 -ffunction-sections -fdata-sections -fno-exceptions -fno-rtti -fno-use-cxa-atexit -fno-threadsafe-statics -fno-stack-protector -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=0 -DNDEBUG -DIMGUI_ENABLE_STB_TRUETYPE"
+
+INCLUDE="-I$IMGUI_DIR -I$IMGUI_SRC"
+
+echo "Compiling C runtime shim..."
+gcc $C_FLAGS $INCLUDE \
+    -c $BRIDGE_SRC/crtshim.c \
+    -o lib/imgui_crtshim.o || { echo "Failed: crtshim.c"; exit 1; }
+
+echo "Compiling render bridge..."
+# imgbridge is compiled as C++ so it sees cimgui.h function declarations
+# (C++ mode is required; the .c extension is overridden with -x c++)
+g++ $CPP_FLAGS $INCLUDE \
+    -x c++ \
+    -DCIMGUI_DEFINE_ENUMS_AND_STRUCTS \
+    -c $BRIDGE_SRC/imgbridge.c \
+    -o lib/imgui_bridge.o || { echo "Failed: imgbridge.c"; exit 1; }
+
+echo "Compiling cimgui wrapper..."
+g++ $CPP_FLAGS $INCLUDE \
+    -c $IMGUI_DIR/cimgui.cpp \
+    -o lib/imgui_cimgui.o || { echo "Failed: cimgui.cpp"; exit 1; }
+
+echo "Compiling imgui core..."
+g++ $CPP_FLAGS $INCLUDE \
+    -c $IMGUI_SRC/imgui.cpp \
+    -o lib/imgui_core.o || { echo "Failed: imgui.cpp"; exit 1; }
+
+echo "Compiling imgui draw..."
+g++ $CPP_FLAGS $INCLUDE \
+    -c $IMGUI_SRC/imgui_draw.cpp \
+    -o lib/imgui_draw.o || { echo "Failed: imgui_draw.cpp"; exit 1; }
+
+echo "Compiling imgui tables..."
+g++ $CPP_FLAGS $INCLUDE \
+    -c $IMGUI_SRC/imgui_tables.cpp \
+    -o lib/imgui_tables.o || { echo "Failed: imgui_tables.cpp"; exit 1; }
+
+echo "Compiling imgui widgets..."
+g++ $CPP_FLAGS $INCLUDE \
+    -c $IMGUI_SRC/imgui_widgets.cpp \
+    -o lib/imgui_widgets.o || { echo "Failed: imgui_widgets.cpp"; exit 1; }
+
+echo "Compiling imgui demo..."
+g++ $CPP_FLAGS $INCLUDE \
+    -c $IMGUI_SRC/imgui_demo.cpp \
+    -o lib/imgui_demo.o || { echo "Failed: imgui_demo.cpp"; exit 1; }
+
+echo "Archiving cimgui.a..."
+# NOTE: imgui_bridge.o and imgui_crtshim.o are NOT in the archive because
+# compile_link.sh already picks them up individually via find lib/ -name "*.o".
+# Including them here would cause duplicate symbol errors.
+ar rcs lib/cimgui.a \
+    lib/imgui_cimgui.o \
+    lib/imgui_core.o \
+    lib/imgui_draw.o \
+    lib/imgui_tables.o \
+    lib/imgui_widgets.o \
+    lib/imgui_demo.o || { echo "Failed: ar"; exit 1; }
+
+echo "ImGui compiled successfully."
+exit 0

compile_link.sh

@@ -14,9 +14,6 @@ done;
 objstring=lib/stub.o" "$objstring 
 echo "Object Files: "$objstring
 echo " "
-
-# Find libgcc for i386 (needed by LVGL compiled with gcc)
 LIBGCC=$(gcc -m32 -print-libgcc-file-name)
-echo "libgcc: ${LIBGCC}"
-
-ld -m elf_i386 -s --gc-sections -Tlinker.script -o bin/kernel.bin $objstring --start-group lib/liblvgl.a ${LIBGCC} --end-group
+ld -m elf_i386 -s --gc-sections -Tlinker.script -o bin/kernel.bin $objstring \
+    --start-group lib/cimgui.a $LIBGCC --end-group

compile_lvgl.sh

@@ -1,132 +0,0 @@
-#!/usr/bin/env bash
-# compile_lvgl.sh — Download LVGL v9.2 source and compile into lib/liblvgl.a
-# Clone & compile in /tmp (fast container-local fs).
-# Cache liblvgl.a on host mount (/code/lvgl/) to skip rebuild.
-set -e
-
-LVGL_VERSION="v9.2.2"
-LVGL_REPO="https://github.com/lvgl/lvgl.git"
-LVGL_DIR="/tmp/lvgl"
-OBJ_DIR="/tmp/lvgl_obj"
-CONF_DIR="$(pwd)/lvglh"
-OUT_DIR="$(pwd)/lib"
-CACHE_DIR="/code/lvgl"
-
-CC="gcc"
-CFLAGS="-m32 -march=i686 -ffreestanding \
-    -fno-builtin -fno-stack-protector -fno-pic -fno-pie \
-    -O2 -Wall -Wno-unused-function -Wno-unused-variable \
-    -I${CONF_DIR} \
-    -I${LVGL_DIR} \
-    -I${LVGL_DIR}/.. \
-    -DLV_CONF_INCLUDE_SIMPLE"
-
-echo " "
-echo "======================="
-echo " "
-echo "Compiling LVGL..."
-echo " "
-
-# If cached liblvgl.a exists on host mount, just copy it and skip everything
-if [ -f "${CACHE_DIR}/liblvgl.a" ]; then
-    echo "Found cached liblvgl.a in ${CACHE_DIR}, copying to ${OUT_DIR}..."
-    cp "${CACHE_DIR}/liblvgl.a" "${OUT_DIR}/liblvgl.a"
-    echo "(Delete lvgl/liblvgl.a to force a full rebuild.)"
-    echo " "
-    echo "LVGL compilation complete (cached)."
-    echo " "
-    exit 0
-fi
-
-# Clone LVGL into /tmp (container-local)
-rm -rf "$LVGL_DIR"
-echo "Downloading LVGL ${LVGL_VERSION}..."
-git clone --depth 1 --branch "${LVGL_VERSION}" "${LVGL_REPO}" "${LVGL_DIR}" 2>&1
-echo "Download complete."
-
-# Gather all LVGL .c source files (core library only, no demos/examples)
-SOURCES=$(find "${LVGL_DIR}/src" -name '*.c' -not -path '*/test/*')
-TOTAL=$(echo "$SOURCES" | wc -l)
-echo "Found ${TOTAL} LVGL source files."
-
-# Compile each .c file to .o (container-local)
-rm -rf "$OBJ_DIR"
-mkdir -p "$OBJ_DIR"
-
-COUNT=0
-ERRORS=0
-for src in $SOURCES; do
-    COUNT=$((COUNT + 1))
-    rel="${src#${LVGL_DIR}/src/}"
-    obj_path="${OBJ_DIR}/${rel%.c}.o"
-    mkdir -p "$(dirname "$obj_path")"
-
-    if ! $CC $CFLAGS -c "$src" -o "$obj_path" 2>&1; then
-        echo "FAILED: $rel"
-        ERRORS=$((ERRORS + 1))
-    fi
-
-    if [ $((COUNT % 50)) -eq 0 ]; then
-        echo "  Compiled ${COUNT}/${TOTAL}..."
-    fi
-done
-
-echo "Compiled ${COUNT} files (${ERRORS} errors)."
-
-if [ "$ERRORS" -ne 0 ]; then
-    echo "LVGL compilation FAILED with ${ERRORS} errors."
-    exit 1
-fi
-
-# Archive into static library
-OBJECTS=$(find "$OBJ_DIR" -name '*.o')
-ar rcs "${OUT_DIR}/liblvgl.a" $OBJECTS
-echo "Created ${OUT_DIR}/liblvgl.a"
-
-# Compile custom LVGL extension files from lvglh/
-LVGLH_SOURCES=$(find "${CONF_DIR}" -name '*.c' 2>/dev/null || true)
-if [ -n "$LVGLH_SOURCES" ]; then
-    echo " "
-    echo "Compiling custom LVGL files from lvglh/..."
-    LVGLH_OBJ_DIR="/tmp/lvglh_obj"
-    rm -rf "$LVGLH_OBJ_DIR"
-    mkdir -p "$LVGLH_OBJ_DIR"
-    HCOUNT=0
-    HERRORS=0
-    for src in $LVGLH_SOURCES; do
-        HCOUNT=$((HCOUNT + 1))
-        rel="${src#${CONF_DIR}/}"
-        obj_path="${LVGLH_OBJ_DIR}/${rel%.c}.o"
-        mkdir -p "$(dirname "$obj_path")"
-        echo "  [lvglh] $rel"
-        if ! $CC $CFLAGS -c "$src" -o "$obj_path" 2>&1; then
-            echo "  FAILED: $rel"
-            HERRORS=$((HERRORS + 1))
-        fi
-    done
-    echo "Compiled ${HCOUNT} custom files (${HERRORS} errors)."
-    if [ "$HERRORS" -ne 0 ]; then
-        echo "Custom LVGL compilation FAILED."
-        exit 1
-    fi
-    # Append custom objects into the existing archive
-    HOBJECTS=$(find "$LVGLH_OBJ_DIR" -name '*.o')
-    ar rcs "${OUT_DIR}/liblvgl.a" $HOBJECTS
-    echo "Updated ${OUT_DIR}/liblvgl.a with custom objects."
-else
-    echo "No custom LVGL files in lvglh/."
-fi
-
-# Cache liblvgl.a and source to host mount for next build
-echo "Caching LVGL to host mount..."
-mkdir -p "$CACHE_DIR"
-rm -rf ${CACHE_DIR}/* ${CACHE_DIR}/.[!.]* ${CACHE_DIR}/..?* 2>/dev/null || true
-cp "${OUT_DIR}/liblvgl.a" "${CACHE_DIR}/liblvgl.a"
-cp -a "$LVGL_DIR/src" "${CACHE_DIR}/src"
-cp -a "$LVGL_DIR"/*.h "${CACHE_DIR}/" 2>/dev/null || true
-cp -a "$OBJ_DIR" "${CACHE_DIR}/obj"
-echo "Done."
-
-echo " "
-echo "LVGL compilation complete."
-echo " "

compile_sources.sh

@@ -4,4 +4,4 @@ echo "======================="
 echo " "
 echo "Compiling FPC Sources..."
 echo " "
-fpc -Aelf -gw -g -gl -n -v0ew -O3 -OpPENTIUM3 -Si -Sc -Sg -Xd -CX -XXs -CfSSE -CfSSE2 -Rintel -Pi386 -Tlinux -FElib/ -Fusrc/* -Fusrc/include/* -Fusrc/driver/* -Fusrc/driver/net/* -Fusrc/driver/bus/* -Fusrc/driver/bus/usb/* -Fusrc/driver/hid/* src/kernel.pas
+fpc -Aelf -gw -g -gl -n -vlewn -O3 -Op3 -Si -Sc -Sg -Xd -CX -XXs -CfSSE -CfSSE2 -Rintel -Pi386 -Tlinux -FElib/ -Fusrc/* -Fusrc/driver/* -Fusrc/driver/net/* -Fusrc/driver/video/* -Fusrc/driver/video/imgui/* src/kernel.pas

dockerout.txt

@@ -0,0 +1,20 @@
+4023:CIMGUI_API float igGetWindowDpiScale(void);
+4081:CIMGUI_API const ImVec4_c* igGetStyleColorVec4(ImGuiCol idx);
+4082:CIMGUI_API ImVec2_c igGetCursorScreenPos(void);
+4084:CIMGUI_API ImVec2_c igGetContentRegionAvail(void);
+4085:CIMGUI_API ImVec2_c igGetCursorPos(void);
+4086:CIMGUI_API float igGetCursorPosX(void);
+4087:CIMGUI_API float igGetCursorPosY(void);
+4091:CIMGUI_API ImVec2_c igGetCursorStartPos(void);
+4350:CIMGUI_API void igBeginDisabled(bool disabled);
+4372:CIMGUI_API ImVec2_c igGetItemRectMin(void);
+4373:CIMGUI_API ImVec2_c igGetItemRectMax(void);
+4374:CIMGUI_API ImVec2_c igGetItemRectSize(void);
+4377:CIMGUI_API ImDrawList* igGetBackgroundDrawList(ImGuiViewport* viewport);
+4378:CIMGUI_API ImDrawList* igGetForegroundDrawList_ViewportPtr(ImGuiViewport* viewport);
+4387:CIMGUI_API ImVec2_c igCalcTextSize(const char* text,const char* text_end,bool hide_text_after_double_hash,float wrap_width);
+4388:CIMGUI_API ImVec4_c igColorConvertU32ToFloat4(ImU32 in);
+4405:CIMGUI_API bool igIsMouseDoubleClicked_Nil(ImGuiMouseButton button);
+5092:CIMGUI_API ImDrawList* igGetForegroundDrawList_WindowPtr(ImGuiWindow* window);
+5161:CIMGUI_API void igBeginDisabledOverrideReenable(void);
+5244:CIMGUI_API bool igIsMouseDoubleClicked_ID(ImGuiMouseButton button,ImGuiID owner_id);

src/contextswitcher.pas

@@ -12,121 +12,15 @@
 //  See the License for the specific language governing permissions and
 //  limitations under the License.
 
-{
-    ContextSwitcher - Custom IRQ0 handler for preemptive context switching.
-
-    Replaces the default ISR_32 with a naked assembly stub that saves the
-    interrupted context (PUSHAD + segment regs), calls a Pascal helper to
-    dispatch timer hooks, send EOI, and run the scheduler, then restores
-    the next process context (or idles) via the returned ESP.
-
-    @author(Kieron Morris <[email protected]>)
+{ 
+	ContextSwitcher - Switch Process Contexts when preempted.
+	
+	@author(Kieron Morris <[email protected]>)
 }
 unit contextswitcher;
 
-{$ASMMODE intel}
-
 interface
 
-uses
-    idt, isrmanager, processmanager, proctypes, util, syslog, tracer;
-
-{ Initialise: overwrite IDT gate 32 with our custom ISR. }
-procedure init;
-
-{ No idle ESP variable needed — idle is now a formal process (PID 0)
-  with its SavedESP managed like any other process. }
-
-implementation
-
-{ -----------------------------------------------------------------------
-  do_context_switch_work
-  Pascal helper called from the assembly ISR.  Receives the current ESP
-  (pointing to the GS..EFLAGS save area), dispatches timer hooks, sends
-  EOI, runs the scheduler and returns the ESP for the next context.
-  Uses register calling convention: saved_esp in EAX, result in EAX.
-  ----------------------------------------------------------------------- }
-function do_context_switch_work(saved_esp : uint32) : uint32;
-var
-    next : PProcessContext;
-begin
-    { 1. Save ESP into the current process }
-    processmanager.CurrentProcess^.SavedESP := saved_esp;
-
-    { 2. Dispatch all hooks registered on interrupt 32 (timer hooks).
-         This fires TMR_0_ISR.Main which in turn fires BDA tick,
-         graphics refresh, USB hotplug, etc. }
-    isrmanager.dispatchHooks(32);
-
-    { 3. Send End-Of-Interrupt to the master PIC }
-    outb($20, $20);
-
-    { 4. Pick the next process to run (always returns non-nil; idle as fallback) }
-    next := processmanager.scheduler_pick_next;
-    processmanager.CurrentProcess := next;
-
-    { 5. Return the selected process ESP }
-    do_context_switch_work := next^.SavedESP;
-end;
-
-{ -----------------------------------------------------------------------
-  context_switch_isr
-  Naked assembly ISR that replaces ISR_32 (IRQ0 / PIT timer).
-
-  Stack on entry (pushed by CPU):
-      [ESP+8] EFLAGS
-      [ESP+4] CS
-      [ESP+0] EIP
-
-  We push general-purpose and segment registers, call the Pascal helper,
-  switch ESP to the returned value, pop registers and IRETD.
-  ----------------------------------------------------------------------- }
-procedure context_switch_isr; assembler; nostackframe;
-asm
-    { Save all general-purpose registers (EAX,ECX,EDX,EBX,ESP,EBP,ESI,EDI) }
-    pushad
-
-    { Save segment registers }
-    push ds
-    push es
-    push fs
-    push gs
-
-    { Load kernel data segments }
-    mov ax, $10
-    mov ds, ax
-    mov es, ax
-    mov fs, ax
-    mov gs, ax
-
-    { Call Pascal helper: EAX = current ESP (register calling convention).
-      Returns new ESP in EAX. }
-    mov eax, esp
-    call do_context_switch_work
-    mov esp, eax
-
-    { Restore segment registers }
-    pop gs
-    pop fs
-    pop es
-    pop ds
-
-    { Restore general-purpose registers }
-    popad
-
-    { Return from interrupt }
-    iretd
-end;
-
-{ -----------------------------------------------------------------------
-  init
-  Override IDT gate 32 with our custom ISR.  Must be called AFTER
-  isrmanager.init so that the default gate has been set up first.
-  ----------------------------------------------------------------------- }
-procedure init;
-begin
-    idt.set_gate(32, uint32(@context_switch_isr), $08, ISR_RING_0);
-    tracer.push_trace('contextswitcher.init');
-end;
+implementation;
 
 end.

src/driver/bus/EHCI.pas

@@ -0,0 +1,65 @@
+//  Copyright 2021 Kieron Morris
+//
+//  Licensed under the Apache License, Version 2.0 (the "License");
+//  you may not use this file except in compliance with the License.
+//  You may obtain a copy of the License at
+//
+//  http://www.apache.org/licenses/LICENSE-2.0
+//
+//  Unless required by applicable law or agreed to in writing, software
+//  distributed under the License is distributed on an "AS IS" BASIS,
+//  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+//  See the License for the specific language governing permissions and
+//  limitations under the License.
+
+{ 
+	Driver->Bus->EHCI - Enhanced Host Controller Interface Driver.
+	
+	@author(Kieron Morris <[email protected]>)
+}
+unit EHCI;
+
+interface
+
+uses
+    tracer,
+    Console,
+    PCI,
+    drivertypes,
+    pmemorymanager,
+    vmemorymanager,
+    util,
+    drivermanagement;
+
+function load : boolean;
+
+implementation
+
+function load : boolean;
+var
+    devices : TDeviceArray;
+    count   : uint32;
+    i       : uint32;
+
+begin
+    tracer.push_trace('EHCI.load');
+    devices:= PCI.getDeviceInfo($0C, $03, $20, count);
+    console.output('USB-EHCI Driver', 'Found ');
+    console.writeint(count);
+    console.writestringln(' USB Controller(s).');
+    if count > 0 then begin
+        for i:=0 to count-1 do begin
+            console.output('USB-EHCI Driver', 'Controller[');
+            console.writeint(i);
+            console.writestring(']: ');
+            console.writehex(devices[i].device_id);
+            console.writestring(' ');
+            console.writehex(devices[i].vendor_id);
+            console.writestring(' ');
+            console.writehexln(devices[i].prog_if);
+        end;
+    end;
+    load:= true;
+end;
+
+end.

src/driver/bus/OHCI.pas

@@ -0,0 +1,96 @@
+//  Copyright 2021 Kieron Morris
+//
+//  Licensed under the Apache License, Version 2.0 (the "License");
+//  you may not use this file except in compliance with the License.
+//  You may obtain a copy of the License at
+//
+//  http://www.apache.org/licenses/LICENSE-2.0
+//
+//  Unless required by applicable law or agreed to in writing, software
+//  distributed under the License is distributed on an "AS IS" BASIS,
+//  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+//  See the License for the specific language governing permissions and
+//  limitations under the License.
+
+{ 
+	Driver->Bus->OHCI - Open Host Controller Interface Driver.
+	
+	@author(Kieron Morris <[email protected]>)
+}
+unit OHCI;
+
+interface
+
+uses
+    tracer,
+    Console,
+    PCI,
+    drivertypes,
+    pmemorymanager,
+    vmemorymanager,
+    util,
+    drivermanagement;
+
+type
+    POHCI_MMR = ^TOHCI_MMR;
+    TOHCI_MMR = packed record
+        HcRevision : uint32;
+        HcControl  : uint32;
+        HcCommandStatus : uint32;
+        HcIntStatus  : uint32;
+        HcIntEnable  : uint32;
+        HcIntDisable : uint32;
+        HcHCCA : uint32;
+        HcPeriodCurrentED : uint32;
+        HcControlHeadED : uint32;
+        HcControlCurrentED : uint32;
+        HcBulkHeadED : uint32;
+        HcBulkCurrentED : uint32;
+        HcDoneHead : uint32;
+        HcFmRemaining : uint32;
+        HcFmNumber : uint32;
+        HcPeriodicStart : uint32;
+        HcLSThreshold : uint32;
+        HcRhDescriptorA : uint32;
+        HcRhDescriptorB : uint32;
+        HcRhStatus : uint32;
+    end;
+
+function load : boolean;
+
+implementation
+
+function load : boolean;
+var
+    devices : TDeviceArray;
+    count   : uint32;
+    i       : uint32;
+    block   : uint32;
+    MMR     : POHCI_MMR;
+
+begin
+    tracer.push_trace('OHCI.load');
+    devices:= PCI.getDeviceInfo($0C, $03, $10, count);
+    console.output('USB-OHCI Driver', 'Found ');
+    console.writeint(count);
+    console.writestringln(' USB Controller(s).');
+    if count > 0 then begin
+        for i:=0 to count-1 do begin
+            console.output('USB-OHCI Driver', 'Controller[');
+            console.writeint(i);
+            console.writestring(']: ');
+            console.writehex(devices[i].device_id);
+            console.writestring(' ');
+            console.writehex(devices[i].vendor_id);
+            console.writestring(' ');
+            console.writehexln(devices[i].prog_if);
+            block:= devices[i].address0 SHR 22;
+            force_alloc_block(block, 0);
+            map_page(block, block);
+            MMR:= POHCI_MMR(devices[i].address0);
+        end;
+    end;
+    load:= true;
+end;
+
+end.