Feat power button

common/cmdline.c

@@ -58,6 +58,9 @@ bool_cmd("qemu_console", opt_qemu_console);
 bool opt_poweroff = true;
 bool_cmd("poweroff", opt_poweroff);
 
+bool opt_power_button = false;
+bool_cmd("power_button", opt_power_button);
+
 static char opt_com1[20];
 string_cmd("com1", opt_com1);
 

common/cpu.c

@@ -49,6 +49,7 @@ static void init_cpu(cpu_t *cpu, unsigned int id, bool is_bsp, bool enabled) {
 
     cpu->percpu = get_percpu_page(id);
     BUG_ON(!cpu->percpu);
+    cpu->percpu->cpu = cpu;
 
     cpu->lock = SPINLOCK_INIT;
     list_init(&cpu->task_queue);

common/setup.c

@@ -55,6 +55,7 @@
 #include <drivers/hpet.h>
 #include <drivers/pic.h>
 #include <drivers/pit.h>
+#include <drivers/power_button.h>
 #include <drivers/serial.h>
 #include <drivers/vga.h>
 
@@ -283,6 +284,9 @@ void __noreturn __text_init kernel_start(uint32_t multiboot_magic, unsigned long
         enable_fpu();
     }
 
+    if (opt_power_button)
+        init_power_button();
+
 #ifdef KTF_PMU
     printk("Initializing PFM library\n");
 

drivers/power_button.c

@@ -0,0 +1,68 @@
+#include <acpi_ktf.h>
+#include <drivers/power_button.h>
+
+static void default_handler(void *);
+
+/** power button press handler */
+static pb_handler_t pb_handler = default_handler;
+/** context passed to the power button press handler */
+static void *pb_context = NULL;
+
+#ifdef KTF_ACPICA
+static UINT32 button_handler(void *Context) {
+    if (ACPI_FAILURE(AcpiClearEvent(ACPI_EVENT_POWER_BUTTON)))
+        panic("PWRB: Failed to clear power button event");
+
+    if (pb_handler)
+        pb_handler(pb_context);
+
+    return ACPI_INTERRUPT_HANDLED;
+}
+#endif
+
+static void default_handler(void *notused) {
+#ifdef KTF_ACPICA
+    acpi_power_off();
+#endif
+}
+
+void pb_set_handler(pb_handler_t handler, void *context) {
+    // check that we are on the bsp. Assumes that there is no task migration
+    ASSERT(is_cpu_bsp(get_this_cpu()));
+
+    unsigned long flags = interrupts_disable_save();
+    pb_handler = handler;
+    pb_context = context;
+    interrupts_restore(flags);
+}
+
+bool init_power_button() {
+#ifdef KTF_ACPICA
+    ACPI_TABLE_FADT *fadt = acpi_find_table(ACPI_SIG_FADT);
+
+    if (!(fadt->Flags & ACPI_FADT_POWER_BUTTON)) {
+        printk("PWRB: Configuring ACPI 'fixed' power button handling\n");
+
+        if (ACPI_FAILURE(AcpiClearEvent(ACPI_EVENT_POWER_BUTTON))) {
+            warning("PWRB: Failed to clear power button event");
+            return false;
+        }
+
+        if (ACPI_FAILURE(AcpiInstallFixedEventHandler(ACPI_EVENT_POWER_BUTTON,
+                                                      button_handler, NULL))) {
+            warning("PWRB: Failed to install power button handler");
+            return false;
+        }
+    }
+    else {
+        warning("PWRB: Non-fixed power button not implemented\n");
+        return false;
+    }
+
+    return true;
+#else
+    warning("PWRB: Power button without ACPICA not implemented\n");
+
+    return false;
+#endif
+}

include/cmdline.h

@@ -67,6 +67,7 @@ extern bool opt_hpet;
 extern bool opt_fpu;
 extern bool opt_qemu_console;
 extern bool opt_poweroff;
+extern bool opt_power_button;
 extern bool opt_fb_scroll;
 extern unsigned long opt_reboot_timeout;
 extern bool opt_tlb_global;

include/cpu.h

@@ -67,6 +67,10 @@ extern void wait_for_all_cpus(void);
 
 /* Static declarations */
 
+static inline cpu_t *get_this_cpu() {
+    return PERCPU_GET(cpu);
+}
+
 static inline bool is_cpu_bsp(cpu_t *cpu) {
     return cpu->flags.bsp;
 }

include/drivers/power_button.h

@@ -0,0 +1,18 @@
+#ifndef KTF_POWER_BUTTON_H
+#define KTF_POWER_BUTTON_H
+
+typedef void (*pb_handler_t)(void *);
+
+/**
+ * Set a handler for the power button. Useful to control experiments.
+ *
+ * Note: This function MUST be called from the bsp to ensure consistency!
+ */
+void pb_set_handler(pb_handler_t handler, void *context);
+
+/**
+ * Initialize power button handling. Requires ACPICA library.
+ */
+extern bool init_power_button();
+
+#endif /* KTF_POWER_BUTTON_H */

include/percpu.h

@@ -31,6 +31,7 @@
 #include <list.h>
 #include <page.h>
 
+struct cpu;
 struct percpu {
     list_head_t list;
 
@@ -60,6 +61,7 @@ struct percpu {
     unsigned long usermode_private;
     volatile unsigned long apic_ticks;
     bool apic_timer_enabled;
+    struct cpu *cpu;
 } __aligned(PAGE_SIZE);
 typedef struct percpu percpu_t;