From d52af2ac94fa2cf370fb64516da2810a21d2a88d Mon Sep 17 00:00:00 2001
From: Alexander Boettcher <alexander.boettcher@genode-labs.com>
Date: Wed, 17 Apr 2024 11:52:16 +0200
Subject: [PATCH] os: avoid state names in system ROM

for ahci/gpu/nvme. Instead conclude from empty and non empty system state
to resume or stop driver.

Issue #5180
---
 repos/os/src/drivers/ahci/main.cc      | 15 +++++++++++----
 repos/os/src/drivers/gpu/intel/main.cc | 13 +++++++++++--
 repos/os/src/drivers/nvme/main.cc      | 12 ++++++++++--
 3 files changed, 32 insertions(+), 8 deletions(-)

diff --git a/repos/os/src/drivers/ahci/main.cc b/repos/os/src/drivers/ahci/main.cc
index 476726b3e1..ede3581e5a 100644
--- a/repos/os/src/drivers/ahci/main.cc
+++ b/repos/os/src/drivers/ahci/main.cc
@@ -129,7 +129,10 @@ class Ahci::Driver : Noncopyable
 			auto state = _system_rom->xml().attribute_value("state",
 			                                                String<32>(""));
 
-			if (state == "driver_stop") {
+			bool const resume_driver =  _schedule_stop && state == "";
+			bool const stop_driver   = !_schedule_stop && state != "";
+
+			if (stop_driver) {
 				_schedule_stop = true;
 
 				for_each_port([&](auto &port, auto, auto) {
@@ -138,14 +141,16 @@ class Ahci::Driver : Noncopyable
 
 				device_release_if_stopped_and_idle();
 
+				log("driver halted");
+
 				return;
 			}
 
-			if (state == "driver_reinit") {
-				_resources.acquire_device();
-
+			if (resume_driver) {
 				_schedule_stop = false;
 
+				_resources.acquire_device();
+
 				/* re-start request handling of client sessions */
 				for_each_port([&](auto &port, auto const index, auto) {
 					port.stop_processing = false;
@@ -153,6 +158,8 @@ class Ahci::Driver : Noncopyable
 					_dispatch.session(index);
 				});
 
+				log("driver resumed");
+
 				return;
 			}
 		}
diff --git a/repos/os/src/drivers/gpu/intel/main.cc b/repos/os/src/drivers/gpu/intel/main.cc
index 50d035ffdd..171bac8e53 100644
--- a/repos/os/src/drivers/gpu/intel/main.cc
+++ b/repos/os/src/drivers/gpu/intel/main.cc
@@ -1204,13 +1204,19 @@ struct Igd::Device
 
 	void handle_system_update(String<32> const & state)
 	{
-		if (state == "driver_stop") {
+		bool const resume_driver =  _schedule_stop && state == "";
+		bool const stop_driver   = !_schedule_stop && state != "";
+
+		if (stop_driver) {
 			_schedule_stop = true;
 			device_release_if_stopped_and_idle();
+
+			log("driver halted");
+
 			return;
 		}
 
-		if (state == "driver_reinit") {
+		if (resume_driver) {
 			_resources.acquire_device();
 
 			_resources.with_mmio([&](auto &mmio) {
@@ -1231,6 +1237,9 @@ struct Igd::Device
 					} else
 						warning("setup_ring_vram failed");
 				});
+
+				log("driver resumed");
+
 			}, []() {
 				error("reinit - failed");
 			});
diff --git a/repos/os/src/drivers/nvme/main.cc b/repos/os/src/drivers/nvme/main.cc
index 76091f54b5..34f09ab654 100644
--- a/repos/os/src/drivers/nvme/main.cc
+++ b/repos/os/src/drivers/nvme/main.cc
@@ -1952,18 +1952,26 @@ class Nvme::Driver : Genode::Noncopyable
 			auto state = _system_rom->xml().attribute_value("state",
 			                                                String<32>(""));
 
-			if (state == "driver_stop") {
+			bool const resume_driver =  _stop_processing && state == "";
+			bool const stop_driver   = !_stop_processing && state != "";
+
+			if (stop_driver) {
 				_stop_processing = true;
 				device_release_if_stopped_and_idle();
+
+				log("driver halted");
+
 				return;
 			}
 
-			if (state == "driver_reinit") {
+			if (resume_driver) {
 				_stop_processing = false;
 
 				_nvme_ctrlr.construct(_env, _platform, _delayer, _irq_sigh);
 				reinit(*_nvme_ctrlr);
 
+				log("driver resumed");
+
 				/* restart block session handling */
 				Signal_transmitter(_restart_sigh).submit();