genode/repos/os/src/drivers/platform/spec/x86/irq.cc

302 lines
7.4 KiB
C++

/*
* \brief Implementation of shared IRQs in platform driver
* \author Alexander Boettcher
* \date 2015-03-27
*/
/*
* Copyright (C) 2015-2017 Genode Labs GmbH
*
* This file is part of the Genode OS framework, which is distributed
* under the terms of the GNU Affero General Public License version 3.
*/
/* Genode includes */
#include <util/bit_allocator.h>
#include <base/log.h>
#include <irq_session/connection.h>
/* Platform driver include */
#include "irq.h"
#include "pci_session_component.h"
namespace Platform {
class Irq_component;
class Irq_allocator;
}
using Genode::size_t;
using Genode::addr_t;
/**
* A simple allocator implementation used by the Irq_proxy
*/
class Platform::Irq_allocator
{
private:
/*
* We partition the IRQ space (128 GSIs) into 40 legacy IRQs and 64 MSIs (and
* hope the partitions will never overlap on any bizarre platform.)
*/
enum { LEGACY = 40, MSI = 64, LEGACY_ARRAY = 64 };
Genode::Bit_array<LEGACY_ARRAY> _legacy { };
Genode::Bit_allocator<MSI> _msi { };
public:
Irq_allocator()
{
/* reserve the last 24 legacy IRQs - 40 IRQs remaining */
_legacy.set(LEGACY, LEGACY_ARRAY - LEGACY);
}
unsigned alloc_msi()
{
try {
return _msi.alloc();
} catch (Genode::Bit_allocator<MSI>::Out_of_indices) { return ~0U; }
}
void free_msi(unsigned msi) { _msi.free(msi); }
bool alloc_irq(addr_t addr)
{
try {
_legacy.set(addr, 1);
return true;
} catch (...) {
return false;
}
}
};
/**
* One allocator for managing in use IRQ numbers and one IRQ thread waiting
* for Genode signals of all hardware IRQs.
*/
static Platform::Irq_allocator irq_alloc;
/**
* Irq_proxy interface implementation
*/
class Platform::Irq_component : public Platform::Irq_proxy
{
private:
Genode::Irq_connection _irq;
Genode::Signal_handler<Platform::Irq_component> _irq_dispatcher;
bool _associated;
public:
void _ack_irq() {
/*
* Associate handler only when required, because our partner may
* also implement shared irq and would expect to get ack_irq()
* form us even if we have no client ...
*/
if (!_associated) {
_associated = true;
/* register signal handler on irq_session */
_irq.sigh(_irq_dispatcher);
}
_irq.ack_irq();
}
virtual bool remove_sharer(Platform::Irq_sigh *s) override {
if (!Irq_proxy::remove_sharer(s))
return false;
/* De-associate handler. */
_associated = false;
_irq.sigh(Genode::Signal_context_capability());
return true;
}
public:
Irq_component(Genode::Env &env, unsigned gsi,
Genode::Irq_session::Trigger trigger,
Genode::Irq_session::Polarity polarity)
:
Irq_proxy(gsi),
_irq(env, gsi, trigger, polarity),
_irq_dispatcher(env.ep(), *this, &Platform::Irq_proxy::notify_about_irq),
_associated(false)
{ }
static Irq_component *get_irq_proxy(unsigned irq_number,
Irq_allocator *irq_alloc = nullptr,
Genode::Irq_session::Trigger trigger = Genode::Irq_session::TRIGGER_UNCHANGED,
Genode::Irq_session::Polarity polarity = Genode::Irq_session::POLARITY_UNCHANGED,
Genode::Env *env = nullptr,
Genode::Allocator *heap = nullptr)
{
static Genode::List<Irq_proxy> proxies;
static Genode::Mutex proxies_mutex;
Genode::Mutex::Guard mutex_guard(proxies_mutex);
/* lookup proxy in database */
for (Irq_proxy *p = proxies.first(); p; p = p->next())
if (p->irq_number() == irq_number)
return static_cast<Irq_component *>(p);
/* try to create proxy */
if (!irq_alloc || !env || !heap || !irq_alloc->alloc_irq(irq_number))
return 0;
Irq_component *new_proxy = new (heap) Irq_component(*env, irq_number, trigger,
polarity);
proxies.insert(new_proxy);
return new_proxy;
}
};
/*******************************
** PCI IRQ session component **
*******************************/
void Platform::Irq_session_component::ack_irq()
{
if (msi()) {
_irq_conn->ack_irq();
return;
}
/* shared irq handling */
Irq_component *irq_obj = Irq_component::get_irq_proxy(_gsi);
if (!irq_obj) {
Genode::error("expected to find IRQ proxy for IRQ ", Genode::Hex(_gsi));
return;
}
if (irq_obj->ack_irq())
irq_obj->_ack_irq();
}
Platform::Irq_session_component::Irq_session_component(unsigned irq,
addr_t pci_config_space,
Genode::Env &env,
Genode::Allocator &heap)
:
_gsi(irq)
{
if (pci_config_space != ~0UL) {
/* msi way */
unsigned msi = irq_alloc.alloc_msi();
if (msi != ~0U) {
try {
using namespace Genode;
_irq_conn.construct(env, msi, Irq_session::TRIGGER_UNCHANGED,
Irq_session::POLARITY_UNCHANGED,
pci_config_space);
_msi_info = _irq_conn->info();
if (_msi_info.type == Irq_session::Info::Type::MSI) {
_gsi = msi;
return;
}
} catch (Genode::Service_denied) { }
irq_alloc.free_msi(msi);
}
}
/* invalid irq number for pci_devices */
if (_gsi >= INVALID_IRQ)
return;
Genode::Irq_session::Trigger trigger;
Genode::Irq_session::Polarity polarity;
_gsi = Platform::Irq_override::irq_override(_gsi, trigger, polarity);
if (_gsi != irq || trigger != Genode::Irq_session::TRIGGER_UNCHANGED ||
polarity != POLARITY_UNCHANGED) {
Genode::log("IRQ override ", irq, "->", _gsi, ", "
"trigger mode: ", trigger, ", ", "polarity: ", polarity);
}
try {
/* check if shared IRQ object was used before */
if (Irq_component::get_irq_proxy(_gsi, &irq_alloc, trigger,
polarity, &env, &heap))
return;
} catch (Genode::Service_denied) { }
Genode::error("unavailable IRQ ", Genode::Hex(_gsi), " requested");
}
Platform::Irq_session_component::~Irq_session_component()
{
if (msi()) {
_irq_conn->sigh(Genode::Signal_context_capability());
irq_alloc.free_msi(_gsi);
return;
}
/* shared irq handling */
Irq_component *irq_obj = Irq_component::get_irq_proxy(_gsi);
if (!irq_obj) return;
if (_irq_sigh.valid())
irq_obj->remove_sharer(&_irq_sigh);
}
void Platform::Irq_session_component::sigh(Genode::Signal_context_capability sigh)
{
if (_irq_conn.constructed()) {
/* register signal handler for msi directly at parent */
_irq_conn->sigh(sigh);
return;
}
/* shared irq handling */
Irq_component *irq_obj = Irq_component::get_irq_proxy(_gsi);
if (!irq_obj) {
Genode::error("signal handler got not registered - irq object unavailable");
return;
}
Genode::Signal_context_capability old = _irq_sigh;
if (old.valid() && !sigh.valid())
irq_obj->remove_sharer(&_irq_sigh);
_irq_sigh = sigh;
if (!old.valid() && sigh.valid())
irq_obj->add_sharer(&_irq_sigh);
}
unsigned short Platform::Irq_routing::rewrite(unsigned char bus, unsigned char dev,
unsigned char, unsigned char pin)
{
unsigned const bridge_bdf_bus = Platform::bridge_bdf(bus);
for (Irq_routing *i = list()->first(); i; i = i->next()) {
if ((dev == i->_device) && (pin - 1 == i->_device_pin) &&
(i->_bridge_bdf == bridge_bdf_bus))
return i->_gsi;
}
return 0;
}