platform_drv/x86: support ACPI reset

Evaluate fadt xml node in report from acpi_drv. If the io ports in the range
of 0xcf8+4 are necessary for the reset than the platform driver will
react on the 'system' state 'reset' and reboot.

Issue #1962

repos/base/run/platform_drv.inc

@@ -51,6 +51,24 @@ proc platform_drv_policy {} {
 }
 
 proc platform_drv_priority {} { return "" }
+proc platform_drv_add_routing {} {
+	if {[have_spec acpi]} {
+		return {
+			<service name="ROM" label="system"> <child name="acpi_report_rom"/> </service>}
+	}
+
+	return ""
+}
+
+proc platform_drv_config_config {} {
+	if {[have_spec acpi] || [have_spec arm] || [have_spec hw_x86_64_muen]} {
+		return {
+		<config>}
+	}
+
+	return {
+		<config acpi="no">}
+}
 
 proc append_platform_drv_config {} {
 	global config
@@ -108,6 +126,8 @@ proc append_platform_drv_config {} {
 		</provides>
 		<route>}
 
+		append config "[platform_drv_add_routing]"
+
 		append_if [have_spec acpi] config {
 			<service name="ROM" label="acpi"> <child name="acpi_report_rom"/> </service>}
 
@@ -118,18 +138,7 @@ proc append_platform_drv_config {} {
 			<any-service> <parent/> </any-service>
 		</route>}
 
-		if {[have_spec acpi] || [have_spec arm] || [have_spec hw_x86_64_muen]} {
-
-		append config {
-		<config>}
-
-		} else {
-
-		append config {
-		<config acpi="no">}
-
-		}
-
+		append config [platform_drv_config_config]
 		append config [platform_drv_policy]
 
 		append config {

repos/libports/run/acpica.run

@@ -27,6 +27,18 @@ proc platform_drv_policy {} {
 			<policy label="acpica"> <pci class="ALL"/> </policy>}
 }
 
+# add routing information to dynamically generate change of 'system' ROM
+proc platform_drv_add_routing {} {
+	return {
+			<service name="ROM" label="system"> <child name="dynamic_rom"/> </service>}
+}
+
+# override default config to react on 'system' ROM changes for reset
+proc platform_drv_config_config {} {
+	return {
+		<config acpi="yes" system="no">}
+}
+
 append_platform_drv_build_components
 
 build $build_components

repos/os/src/drivers/platform/spec/x86/main.cc

@@ -39,7 +39,10 @@ struct Platform::Main
 	Genode::Lazy_volatile_object<Genode::Attached_rom_dataspace> acpi_rom;
 	Genode::Lazy_volatile_object<Platform::Root> root;
 
+	Genode::Lazy_volatile_object<Genode::Attached_rom_dataspace> system_state;
+
 	Genode::Signal_handler<Platform::Main> _acpi_report;
+	Genode::Signal_handler<Platform::Main> _system_report;
 
 	void acpi_update()
 	{
@@ -54,19 +57,48 @@ struct Platform::Main
 		_env.parent().announce(_env.ep().manage(*root));
 	}
 
+	void system_update()
+	{
+		system_state->update();
+
+		if (!system_state->is_valid() || !root.is_constructed())
+			return;
+
+		Genode::Xml_node system(system_state->local_addr<char>(),
+		                        system_state->size());
+
+		typedef Genode::String<16> Value;
+		const Value state = system.attribute_value("state", Value("unknown"));
+
+		if (state == "reset")
+			root->system_reset();
+	}
+
 	Main(Genode::Env &env)
 	:
 		sliced_heap(env.ram(), env.rm()),
 		_env(env),
-		_acpi_report(_env.ep(), *this, &Main::acpi_update)
+		_acpi_report(_env.ep(), *this, &Main::acpi_update),
+		_system_report(_env.ep(), *this, &Main::system_update)
 	{
+		const Genode::Xml_node &config = Genode::config()->xml_node();
+
 		typedef Genode::String<8> Value;
-		Value const wait_for_acpi = Genode::config()->xml_node().attribute_value("acpi", Value("yes"));
+		Value const wait_for_acpi = config.attribute_value("acpi", Value("yes"));
 
 		if (wait_for_acpi == "yes") {
+			bool system_reset = config.attribute_value("system", false);
+			if (system_reset) {
+				/* wait for system state changes and react upon, e.g. reset */
+				system_state.construct("system");
+				system_state->sigh(_system_report);
+			}
+
 			/* for ACPI support, wait for the first valid acpi report */
 			acpi_rom.construct("acpi");
 			acpi_rom->sigh(_acpi_report);
+			/* check if already valid */
+			acpi_update();
 			return;
 		}
 

repos/os/src/drivers/platform/spec/x86/pci_config_access.h

@@ -24,7 +24,7 @@ namespace Platform {
 	{
 		private:
 
-			enum { REG_ADDR = 0xcf8, REG_DATA = 0xcfc };
+			enum { REG_ADDR = 0xcf8, REG_DATA = 0xcfc, REG_SIZE = 4 };
 
 			/**
 			 * Request interface to access an I/O port
@@ -47,7 +47,7 @@ namespace Platform {
 				 * Once created, each I/O-port session persists until
 				 * the PCI driver gets killed by its parent.
 				 */
-				static Genode::Io_port_connection io_port(port, 4);
+				static Genode::Io_port_connection io_port(port, REG_SIZE);
 				return &io_port;
 			}
 
@@ -177,6 +177,32 @@ namespace Platform {
 					return true;
 				}
 			}
+
+			bool reset_support(unsigned reg, unsigned reg_size) const
+			{
+				return (REG_ADDR <= reg) &&
+				       reg + reg_size <= REG_ADDR + REG_SIZE;
+			}
+
+			bool system_reset(unsigned reg, unsigned long long value,
+			                  const Device::Access_size &access_size)
+			{
+				switch (access_size) {
+				case Device::ACCESS_8BIT:
+					_io_port<REG_ADDR>()->outb(reg, value);
+					break;
+				case Device::ACCESS_16BIT:
+					_io_port<REG_ADDR>()->outw(reg, value);
+					break;
+				case Device::ACCESS_32BIT:
+					_io_port<REG_ADDR>()->outl(reg, value);
+					break;
+				default:
+					return false;
+				}
+
+				return true;
+			}
 	};
 }
 

repos/os/src/drivers/platform/spec/x86/pci_session_component.h

@@ -23,6 +23,7 @@
 #include <root/component.h>
 #include <root/client.h>
 
+#include <util/mmio.h>
 #include <util/retry.h>
 #include <util/volatile_object.h>
 
@@ -853,6 +854,27 @@ class Platform::Root : public Genode::Root_component<Session_component>
 {
 	private:
 
+		struct Fadt {
+			Genode::uint32_t features = 0, reset_type = 0, reset_value = 0;
+			Genode::uint64_t reset_addr = 0;
+
+			/* Table 5-35 Fixed ACPI Description Table Fixed Feature Flags */
+			struct Features : Genode::Register<32> {
+				struct Reset : Bitfield<10, 1> { };
+			};
+
+			/* ACPI spec - 5.2.3.2 Generic Address Structure */
+			struct Gas : Genode::Register<32>
+			{
+				struct Address_space : Bitfield <0, 8> {
+					enum { SYSTEM_IO = 1 };
+				};
+				struct Access_size : Bitfield<24,8> {
+					enum { UNDEFINED = 0, BYTE = 1, WORD = 2, DWORD = 3, QWORD = 4};
+				};
+			};
+		} fadt;
+
 		Genode::Rpc_entrypoint _device_pd_ep;
 
 		void _parse_report_rom(const char * acpi_rom)
@@ -938,6 +960,13 @@ class Platform::Root : public Genode::Root_component<Session_component>
 					}
 				}
 
+				if (node.has_type("fadt")) {
+					node.attribute("features").value(&fadt.features);
+					node.attribute("reset_type").value(&fadt.reset_type);
+					node.attribute("reset_addr").value(&fadt.reset_addr);
+					node.attribute("reset_value").value(&fadt.reset_value);
+				}
+
 				if (!node.has_type("routing"))
 					continue;
 
@@ -1029,4 +1058,47 @@ class Platform::Root : public Genode::Root_component<Session_component>
 				}
 			}
 		}
+
+		void system_reset()
+		{
+			const bool io_port_space = (Fadt::Gas::Address_space::get(fadt.reset_type) == Fadt::Gas::Address_space::SYSTEM_IO);
+
+			if (!io_port_space)
+				return;
+
+			Config_access config_access;
+			const unsigned raw_access_size = Fadt::Gas::Access_size::get(fadt.reset_type);
+			const bool reset_support = config_access.reset_support(fadt.reset_addr, raw_access_size);
+			if (!reset_support)
+				return;
+
+			const bool feature_reset = Fadt::Features::Reset::get(fadt.features);
+
+			if (!feature_reset) {
+				PWRN("system reset failed - feature not supported");
+				return;
+			}
+
+			Device::Access_size access_size = Device::ACCESS_8BIT;
+
+			unsigned raw_size = Fadt::Gas::Access_size::get(fadt.reset_type);
+			switch (raw_size) {
+			case Fadt::Gas::Access_size::WORD:
+				access_size = Device::ACCESS_16BIT;
+				break;
+			case Fadt::Gas::Access_size::DWORD:
+				access_size = Device::ACCESS_32BIT;
+				break;
+			case Fadt::Gas::Access_size::QWORD:
+				PERR("system reset failed - unsupported access size");
+				return;
+			default:
+				break;
+			}
+
+			config_access.system_reset(fadt.reset_addr, fadt.reset_value,
+			                           access_size);
+			/* if we are getting here - the reset failed */
+			PINF("system reset failed");
+		}
 };