more interrupt work

kernel/include/framebuffer.h

@@ -0,0 +1,23 @@
+/* Calcite, kernel/include/framebuffer.h
+ * Copyright 2025 Benji Dial
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or (at
+ * your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program. If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#include <stdint.h>
+
+extern uint8_t *fb_base;
+extern int fb_width;
+extern int fb_height;
+extern int fb_pitch;

kernel/include/keyboard.h

@@ -0,0 +1,20 @@
+/* Calcite, kernel/include/keyboard.h
+ * Copyright 2025 Benji Dial
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program. If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+void on_keyboard_irq();

kernel/src/entry.c

@@ -15,7 +15,9 @@
  * this program. If not, see <https://www.gnu.org/licenses/>.
  */
 
+#include <framebuffer.h>
 #include <interrupts.h>
+#include <keyboard.h>
 #include <utility.h>
 #include <initfs.h>
 #include <limine.h>
@@ -75,11 +77,6 @@ static void map_kernel_region(
       physical_start + i, (uint8_t *)virtual_start + i, writable, executable);
 }
 
-static uint8_t *fb_base;
-static int fb_width;
-static int fb_height;
-static int fb_pitch;
-
 static uint8_t *initfs_start;
 static uint64_t initfs_length;
 
@@ -179,11 +176,17 @@ static uint64_t initfs_length;
 
 [[noreturn]] static void with_kernel_page_tables() {
 
-  //further initialization
+  //set initfs
 
   set_initfs(initfs_start, initfs_length);
+
+  //set up interrupts
+
+  set_irq_handler(0x01, &on_keyboard_irq);
   enable_interrupts();
 
+  //halt repeatedly
+
   while (1)
     __asm__ ("hlt");
 

kernel/src/framebuffer.c

@@ -0,0 +1,23 @@
+/* Calcite, kernel/src/framebuffer.c
+ * Copyright 2025 Benji Dial
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or (at
+ * your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program. If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#include <framebuffer.h>
+
+uint8_t *fb_base;
+int fb_width;
+int fb_height;
+int fb_pitch;

kernel/src/interrupts.c

@@ -192,8 +192,8 @@ void enable_interrupts_asm(
 
 void enable_interrupts() {
 
-  the_tss.ist1 = (uint64_t)&interrupt_stack_one;
+  the_tss.ist1 = (uint64_t)interrupt_stack_one + INTERRUPT_STACK_SIZE;
-  the_tss.ist2 = (uint64_t)&interrupt_stack_two;
+  the_tss.ist2 = (uint64_t)interrupt_stack_two + INTERRUPT_STACK_SIZE;
 
   //having the table past the end of the tss will lead to a gpf when the
   //cpu tries to access it, which is the same effect as a disabled port.

kernel/src/keyboard.asm

@@ -0,0 +1,38 @@
+ ; Calcite, kernel/src/paging.asm
+ ; Copyright 2025 Benji Dial
+ ;
+ ; This program is free software: you can redistribute it and/or modify
+ ; it under the terms of the GNU General Public License as published by
+ ; the Free Software Foundation, either version 3 of the License, or (at
+ ; your option) any later version.
+ ;
+ ; This program is distributed in the hope that it will be useful, but
+ ; WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ ; or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ ; more details.
+ ;
+ ; You should have received a copy of the GNU General Public License along with
+ ; this program. If not, see <https://www.gnu.org/licenses/>.
+
+
+bits 64
+
+section .text
+
+;referenced in keyboard.c
+;return type is int
+;returns -1 if no byte available
+global read_keyboard_byte
+read_keyboard_byte:
+
+  in al, 0x64
+  test al, 0x01
+  jz .no_data
+
+  xor eax, eax
+  in al, 0x60
+  ret
+
+.no_data:
+  mov eax, -1
+  ret

kernel/src/keyboard.c

@@ -0,0 +1,40 @@
+/* Calcite, kernel/src/keyboard.c
+ * Copyright 2025 Benji Dial
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or (at
+ * your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program. If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#include <framebuffer.h>
+#include <keyboard.h>
+
+//defined in keyboard.asm
+//returns -1 if no byte available
+int read_keyboard_byte();
+
+static uint32_t color = 1;
+
+void on_keyboard_irq() {
+
+  while (read_keyboard_byte() != -1)
+    ;
+
+  color ^= color << 13;
+  color ^= color >> 17;
+  color ^= color << 5;
+
+  for (int y = 0; y < fb_height; ++y)
+    for (int x = 0; x < fb_width; ++x)
+      *(uint32_t *)&fb_base[y * fb_pitch + x * 4] = color & 0x00ffffff;
+
+}