Add keyboard driver

11 files changed, 241 insertions, 14 deletions

diff --git a/drivers/keyboard.cc b/drivers/keyboard.cc
new file mode 100644
index 0000000..268ce2b
--- /dev/null
+++ b/drivers/keyboard.cc
@@ -0,0 +1,147 @@
+#include "keyboard.h"
+#include <stdlib.h>
+
+Keyboard::Keyboard() : InterruptHandler(0x01) {
+  // eat all previous keystrikes
+  while (commandport.read() & 0x1) dataport.read();
+  commandport.write(0xae);  // ???
+  commandport.write(0x20);  // get state ???
+  auto status = (dataport.read() | 1) & ~0x10;
+  commandport.write(0x60);  // set state ???
+  dataport.write(status);   // ???
+  dataport.write(0xf4);     // ???
+}
+
+void Keyboard::trigger() {
+  const auto key = dataport.read();
+
+  if (key < 0x80) {
+    switch (key) {
+      case 0x04:
+        printk('3');
+        break;
+      case 0x05:
+        printk('4');
+        break;
+      case 0x06:
+        printk('5');
+        break;
+      case 0x07:
+        printk('6');
+        break;
+      case 0x08:
+        printk('7');
+        break;
+      case 0x09:
+        printk('8');
+        break;
+      case 0x0A:
+        printk('9');
+        break;
+      case 0x0B:
+        printk('0');
+        break;
+
+      case 0x10:
+        printk('q');
+        break;
+      case 0x11:
+        printk('w');
+        break;
+      case 0x12:
+        printk('e');
+        break;
+      case 0x13:
+        printk('r');
+        break;
+      case 0x14:
+        printk('t');
+        break;
+      case 0x15:
+        printk('y');
+        break;
+      case 0x16:
+        printk('u');
+        break;
+      case 0x17:
+        printk('i');
+        break;
+      case 0x18:
+        printk('o');
+        break;
+      case 0x19:
+        printk('p');
+        break;
+
+      case 0x1E:
+        printk('a');
+        break;
+      case 0x1F:
+        printk('s');
+        break;
+      case 0x20:
+        printk('d');
+        break;
+      case 0x21:
+        printk('f');
+        break;
+      case 0x22:
+        printk('g');
+        break;
+      case 0x23:
+        printk('h');
+        break;
+      case 0x24:
+        printk('j');
+        break;
+      case 0x25:
+        printk('k');
+        break;
+      case 0x26:
+        printk('l');
+        break;
+
+      case 0x2C:
+        printk('z');
+        break;
+      case 0x2D:
+        printk('x');
+        break;
+      case 0x2E:
+        printk('c');
+        break;
+      case 0x2F:
+        printk('v');
+        break;
+      case 0x30:
+        printk('b');
+        break;
+      case 0x31:
+        printk('n');
+        break;
+      case 0x32:
+        printk('m');
+        break;
+      case 0x33:
+        printk(',');
+        break;
+      case 0x34:
+        printk('.');
+        break;
+      case 0x35:
+        printk('/');
+        break;
+
+      case 0x1C:
+        printk('\n');
+        break;
+      case 0x39:
+        printk(' ');
+        break;
+
+      default:
+        printk("keyboard interrupt: ", uhex{key}, "\n");
+        break;
+    }
+  }
+}
diff --git a/drivers/keyboard.h b/drivers/keyboard.h
new file mode 100644
index 0000000..a14c2c0
--- /dev/null
+++ b/drivers/keyboard.h
@@ -0,0 +1,15 @@
+#pragma once
+
+#include "idt.h"
+#include "ports.h"
+
+class Keyboard : public InterruptHandler {
+public:
+  Keyboard();
+
+  void trigger() override;
+
+private:
+  keyboard_comm_t commandport;
+  keyboard_data_t dataport;
+};
diff --git a/drivers/makefile b/drivers/makefile
index ad255c4..2a1fa0c 100644
--- a/drivers/makefile
+++ b/drivers/makefile
@@ -1,5 +1,6 @@
 CXX_OBJ += drivers/cga.o \
-	   drivers/serial.o
+	   drivers/serial.o \
+	   drivers/keyboard.o
 
 HWH := drivers/hardware.h
 autogen := $(autogen) $(HWH)
diff --git a/drivers/ports.h b/drivers/ports.h
index f241299..2d26e65 100644
--- a/drivers/ports.h
+++ b/drivers/ports.h
@@ -58,4 +58,6 @@ typedef Port<0x2e8, uint8_t> com4_port_t;
 typedef Port<0x20, uint8_t> pic1_t;
 typedef Port<0xa0, uint8_t> pic2_t;
 
-typedef Port<0x60, uint8_t> kb_t;
+/* PS/2 keyboard */
+typedef Port<0x60, uint8_t> keyboard_data_t;
+typedef Port<0x64, uint8_t> keyboard_comm_t;
diff --git a/src/idt.cc b/src/idt.cc
index fefe53e..68ae260 100644
--- a/src/idt.cc
+++ b/src/idt.cc
@@ -4,7 +4,23 @@
 #include "ports.h"
 
 static_assert(sizeof(IDT::Pointer) == 6);
-static_assert(sizeof(IDT::Entry) == 8);  // size of IDT::Entry in protected mode is 64 bits
+
+static InterruptHandler* handlers[256] = {nullptr};
+
+bool IDT::install(uint8_t irq, InterruptHandler* h) {
+  if (h != nullptr && handlers[irq] == nullptr) {
+    handlers[irq] = h;
+    return true;
+  }
+  return false;
+}
+bool IDT::uninstall(uint8_t irq, InterruptHandler* h) {
+  if (handlers[irq] == h) {
+    handlers[irq] = nullptr;
+    return true;
+  }
+  return false;
+}
 
 /* reinitialize the PIC controllers, giving them specified vector offsets
    rather than 8h and 70h, as configured by default */
@@ -22,7 +38,10 @@ static_assert(sizeof(IDT::Entry) == 8);  // size of IDT::Entry in protected mode
 #define ICW4_SFNM 0x10       /* Special fully nested (not) */
 
 extern "C" uint32_t handle_interrupt(uint8_t irq, uint32_t esp) {
-  printk("interrupt ", uhex{irq}, '\n');
+  if (handlers[irq] != nullptr) {
+    handlers[irq]->trigger();
+  }
+
   pic1_t pic1;
   pic1.write(0x20);
   if (irq > 7) {
@@ -91,7 +110,6 @@ IDT::IDT(const uint16_t selector) {
 
   Pointer ptr{.limit = sizeof(table), .base = reinterpret_cast<uint32_t>(table)};
   asm volatile("lidt %0" : : "m"(ptr));
-  asm volatile("sti");
 
   printk("IDT installed at ", uhex{ptr.base}, '\n');
 }
diff --git a/src/idt.h b/src/idt.h
index bc71f05..3a9848f 100644
--- a/src/idt.h
+++ b/src/idt.h
@@ -2,7 +2,21 @@
 
 #include <types.h>
 
+class InterruptHandler {
+private:
+  const uint8_t m_irq;
+
+protected:
+  InterruptHandler(uint8_t irq);
+  ~InterruptHandler();
+
+public:
+  virtual void trigger();
+};
+
 class IDT {
+  friend class InterruptHandler;
+
 public:
   struct Pointer {
     uint16_t limit;
@@ -19,24 +33,23 @@ public:
   class Entry {
   public:
     constexpr Entry() = default;
-    Entry(void (*handler)(), uint16_t select, InterruptType t) {
-      offset_0_15 = reinterpret_cast<uint32_t>(handler) & 0xffff;
-      offset_16_31 = (reinterpret_cast<uint32_t>(handler) >> 16) & 0xffff;
-      selector = select;
-      type = t;
-    }
+    Entry(void (*handler)(), uint16_t select, InterruptType t);
 
   private:
     uint16_t offset_0_15 = 0;            //  0-15 offset in the segment
     uint16_t selector = 0;               // 16-31 selector of the code segment
     [[maybe_unused]] uint8_t null = 0;   // 32-39 unused in protected mode
     InterruptType type = Null;           // 40-43 type
-    uint16_t offset_16_31 = 0;             // 48-63 offset high
+    uint16_t offset_16_31 = 0;           // 48-63 offset high
   } __attribute__((packed));
 
   IDT(const uint16_t selector);
+  void enable() { asm volatile("sti"); }
 
 private:
   Entry table[256];
+
+  static bool install(uint8_t, InterruptHandler*);
+  static bool uninstall(uint8_t, InterruptHandler*);
 };
 
diff --git a/src/idt/interruptgate.cc b/src/idt/interruptgate.cc
new file mode 100644
index 0000000..0dbcce2
--- /dev/null
+++ b/src/idt/interruptgate.cc
@@ -0,0 +1,10 @@
+#include "../idt.h"
+
+static_assert(sizeof(IDT::Entry) == 8);  // size of IDT::Entry in protected mode is 64 bits
+
+IDT::Entry::Entry(void (*handler)(), uint16_t select, IDT::InterruptType t) {
+  offset_0_15 = reinterpret_cast<uint32_t>(handler) & 0xffff;
+  offset_16_31 = (reinterpret_cast<uint32_t>(handler) >> 16) & 0xffff;
+  selector = select;
+  type = t;
+}
diff --git a/src/idt/interrupthandler.cc b/src/idt/interrupthandler.cc
new file mode 100644
index 0000000..7af830b
--- /dev/null
+++ b/src/idt/interrupthandler.cc
@@ -0,0 +1,14 @@
+#include <stdlib.h>
+#include "../idt.h"
+
+InterruptHandler::InterruptHandler(uint8_t irq) : m_irq(irq) {
+  IDT::install(m_irq, this);
+}
+
+InterruptHandler::~InterruptHandler() {
+  IDT::uninstall(m_irq, this);
+}
+
+void InterruptHandler::trigger() {
+  printk("Unhandled interrupt ", uhex{m_irq}, '\n');
+}
diff --git a/src/kernel.cc b/src/kernel.cc
index 6bfb021..ff8e6bd 100644
--- a/src/kernel.cc
+++ b/src/kernel.cc
@@ -15,6 +15,8 @@
 #include "idt.h"
 #include "serial.h"
 
+#include "keyboard.h"
+
 #include "hardware.h"
 
 typedef void (*constructor)();
@@ -48,6 +50,10 @@ void kernel_main([[maybe_unused]] uint32_t mb_magic, [[maybe_unused]] uint32_t m
   GDT gdt;
   IDT idt{gdt.codeDescriptor()};
 
+  Keyboard kb;
+
+  idt.enable();
+
   while (true) asm volatile("hlt");
 }
 }  // extern "C"
diff --git a/src/makefile b/src/makefile
index 8b21640..dda24af 100644
--- a/src/makefile
+++ b/src/makefile
@@ -7,7 +7,8 @@ CXX_OBJ += src/kernel.o \
 	   src/memory.o \
 	   src/gdt.o \
 	   src/gdt/segmentdescriptor.o \
-	   src/idt.o
+	   src/idt.o \
+	   src/idt/interruptgate.o src/idt/interrupthandler.o
 
 src/cpu/irq.h: $(OBJ_DIR)/src/cpu/exceptions.o $(OBJ_DIR)/src/cpu/interrupts.o
 	@echo "  GEN $@"
diff --git a/toolchain.makefile b/toolchain.makefile
index ee9cc0e..7a64904 100644
--- a/toolchain.makefile
+++ b/toolchain.makefile
@@ -15,7 +15,7 @@ CXX_FLAGS   := -std=c++20 \
 	       -Werror=shadow-all \
 	       -Wold-style-cast -Wconversion \
 	       -Wconsumed
-CXX_INCLUDE := $(CURDIR)/libk $(CURDIR)/drivers
+CXX_INCLUDE := $(CURDIR)/libk $(CURDIR)/src $(CURDIR)/drivers
 CXX_SYSTEM_INCLUDE := $(CURDIR)/grub
 
 #