kernel: Add initial scheduler implementation

Signed-off-by: Ian Moffett <ian@osmora.org>

2 files changed, 62 insertions, 7 deletions

diff --git a/sys/arch/amd64/amd64/local_intr.S b/sys/arch/amd64/amd64/local_intr.S
index abfd9e0..b7b6345 100644
--- a/sys/arch/amd64/amd64/local_intr.S
+++ b/sys/arch/amd64/amd64/local_intr.S
@@ -27,14 +27,19 @@
  * POSSIBILITY OF SUCH DAMAGE.
  */
 
+#include <machine/frameasm.h>
+#include <machine/trap.h>
+#include <sys/cdefs.h>
+
+__KERNEL_META "$Hyra$: local_intr.S, Ian Marco Moffett, \
+               Routines for handling Local Interrupts"
+
 .text
  .globl lapic_tmr_isr
 
 lapic_tmr_isr:
-    lea stub_msg(%rip), %rdi
-    call kprintf
-    cli
-    hlt
-
-.section .rodata
-stub_msg: .ascii "**LAPIC TIMER ISR IS A STUB; HALTING**\n\0"
+    push_trapframe $0
+    mov %rsp, %rdi
+    call sched_context_switch
+    pop_trapframe
+    iretq
diff --git a/sys/arch/amd64/amd64/switch.S b/sys/arch/amd64/amd64/switch.S
new file mode 100644
index 0000000..156012e
--- /dev/null
+++ b/sys/arch/amd64/amd64/switch.S
@@ -0,0 +1,50 @@
+/*
+ * Copyright (c) 2023-2024 Ian Marco Moffett and the Osmora Team.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of Hyra nor the names of its
+ *    contributors may be used to endorse or promote products derived from
+ *    this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+#include <machine/frameasm.h>
+
+__KERNEL_META "$Hyra$: switch.S, Ian Marco Moffett, \
+               Low level context switch code"
+
+.text
+.globl __sched_switch_to
+
+/* void __sched_switch_to(struct trapframe *tf) */
+__sched_switch_to:
+    /* Sanity check */
+    or %rdi, %rdi
+    jz fail
+
+    /* Pop regs and switch */
+    mov %rdi, %rsp
+    pop_trapframe
+    iretq
+fail:
+    retq