From e99326db0ec9e26f45213b2e15fde5c889e4df97 Mon Sep 17 00:00:00 2001
From: Baptiste Wicht <baptiste.wicht@gmail.com>
Date: Sat, 6 Aug 2016 12:22:39 +0200
Subject: [PATCH] Decouple HPET init from ACPI

---
 kernel/include/drivers/hpet.hpp | 2 ++
 kernel/src/acpi.cpp             | 7 -------
 kernel/src/drivers/hpet.cpp     | 6 ++++++
 kernel/src/kernel.cpp           | 2 ++
 4 files changed, 10 insertions(+), 7 deletions(-)

diff --git a/kernel/include/drivers/hpet.hpp b/kernel/include/drivers/hpet.hpp
index 42a24075..daa10d45 100644
--- a/kernel/include/drivers/hpet.hpp
+++ b/kernel/include/drivers/hpet.hpp
@@ -13,6 +13,8 @@ namespace hpet {
 bool install();
 void late_install();
 
+void init();
+
 } //end of namespace hpet
 
 #endif
diff --git a/kernel/src/acpi.cpp b/kernel/src/acpi.cpp
index 10a4d129..77d56b35 100644
--- a/kernel/src/acpi.cpp
+++ b/kernel/src/acpi.cpp
@@ -16,8 +16,6 @@
 #include "arch.hpp"
 #include "assert.hpp"
 
-#include "drivers/hpet.hpp"
-
 namespace {
 
 // This is copied from acexcep.h
@@ -106,11 +104,6 @@ void initialize_acpica(){
     acpi_initialized = true;
 
     logging::logf(logging::log_level::DEBUG, "acpi:: Finished initialization of ACPICA\n");
-
-    // Here we initialize the drivers that need ACPI
-    // TODO This is not good coupling: Find a better solution
-
-    hpet::late_install();
 }
 
 uint64_t acpi_read(const ACPI_GENERIC_ADDRESS& address){
diff --git a/kernel/src/drivers/hpet.cpp b/kernel/src/drivers/hpet.cpp
index 1dee1308..65d2dcbe 100644
--- a/kernel/src/drivers/hpet.cpp
+++ b/kernel/src/drivers/hpet.cpp
@@ -11,6 +11,7 @@
 #include "logging.hpp"
 #include "mmap.hpp"
 #include "arch.hpp"
+#include "scheduler.hpp" // For async init
 
 namespace {
 
@@ -43,6 +44,11 @@ void clear_register_bits(size_t reg, uint64_t bits){
 
 } //End of anonymous namespace
 
+void hpet::init(){
+    // HPET needs ACPI
+    scheduler::queue_async_init_task(hpet::late_install);
+}
+
 bool hpet::install(){
     // Find the HPET table
     auto status = AcpiGetTable(ACPI_SIG_HPET, 0, reinterpret_cast<ACPI_TABLE_HEADER **>(&hpet_table));
diff --git a/kernel/src/kernel.cpp b/kernel/src/kernel.cpp
index bc0bfd38..f31814d9 100644
--- a/kernel/src/kernel.cpp
+++ b/kernel/src/kernel.cpp
@@ -28,6 +28,7 @@
 #include "network.hpp"
 #include "vfs/vfs.hpp"
 #include "fs/sysfs.hpp"
+#include "drivers/hpet.hpp"
 
 extern "C" {
 
@@ -100,6 +101,7 @@ void kernel_main(){
 
     // Asynchronously initialized drivers
     acpi::init();
+    hpet::init();
 
     //Install drivers
     timer::install();