[Patch v7 18/18] x86, irq, ACPI: Implement ACPI driver to support IOAPIC hotplug

Jiang Liu
2014-10-27T05:22:09Z

Enable support of IOAPIC hotplug by:
1) reintroducing ACPI based IOAPIC driver
2) enhance pci_root driver to hook hotplug events

The ACPI IOAPIC driver is always enabled if all of ACPI, PCI and IOAPIC
are enabled.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
---
drivers/acpi/Kconfig | 6 ++
drivers/acpi/Makefile | 1 +
drivers/acpi/internal.h | 7 ++
drivers/acpi/ioapic.c | 235 +++++++++++++++++++++++++++++++++++++++++++++++
drivers/acpi/pci_root.c | 3 +
5 files changed, 252 insertions(+)
create mode 100644 drivers/acpi/ioapic.c

diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
index b23fe37f67c0..127bc2fc43be 100644
--- a/drivers/acpi/Kconfig
+++ b/drivers/acpi/Kconfig
@@ -315,6 +315,12 @@ config ACPI_HOTPLUG_MEMORY
To compile this driver as a module, choose M here:
the module will be called acpi_memhotplug.

+config ACPI_HOTPLUG_IOAPIC
+ bool
+ depends on PCI
+ depends on X86_IO_APIC
+ default y
+
config ACPI_SBS
tristate "Smart Battery System"
depends on X86
diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile
index c3b2fcb729f3..3b283a232f7a 100644
--- a/drivers/acpi/Makefile
+++ b/drivers/acpi/Makefile
@@ -69,6 +69,7 @@ obj-$(CONFIG_ACPI_PROCESSOR) += processor.o
obj-y += container.o
obj-$(CONFIG_ACPI_THERMAL) += thermal.o
obj-y += acpi_memhotplug.o
+obj-$(CONFIG_ACPI_HOTPLUG_IOAPIC) += ioapic.o
obj-$(CONFIG_ACPI_BATTERY) += battery.o
obj-$(CONFIG_ACPI_SBS) += sbshc.o
obj-$(CONFIG_ACPI_SBS) += sbs.o
diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h
index 447f6d679b29..73efdcb8d8ad 100644
--- a/drivers/acpi/internal.h
+++ b/drivers/acpi/internal.h
@@ -35,6 +35,13 @@ void acpi_int340x_thermal_init(void);
int acpi_sysfs_init(void);
void acpi_container_init(void);
void acpi_memory_hotplug_init(void);
+#ifdef CONFIG_ACPI_HOTPLUG_IOAPIC
+int acpi_ioapic_add(struct acpi_pci_root *root);
+int acpi_ioapic_remove(struct acpi_pci_root *root);
+#else
+static inline int acpi_ioapic_add(struct acpi_pci_root *root) { return 0; }
+static inline int acpi_ioapic_remove(struct acpi_pci_root *root) { return 0; }
+#endif
#ifdef CONFIG_ACPI_DOCK
void register_dock_dependent_device(struct acpi_device *adev,
acpi_handle dshandle);
diff --git a/drivers/acpi/ioapic.c b/drivers/acpi/ioapic.c
new file mode 100644
index 000000000000..9a631a61e270
--- /dev/null
+++ b/drivers/acpi/ioapic.c
@@ -0,0 +1,235 @@
+/*
+ * IOAPIC/IOxAPIC/IOSAPIC driver
+ *
+ * Copyright (C) 2009 Fujitsu Limited.
+ * (c) Copyright 2009 Hewlett-Packard Development Company, L.P.
+ *
+ * Copyright (C) 2014 Intel Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Based on original drivers/pci/ioapic.c
+ * Yinghai Lu <yinghai@kernel.org>
+ * Jiang Liu <jiang.liu@intel.com>
+ */
+
+/*
+ * This driver manages I/O APICs added by hotplug after boot.
+ * We try to claim all I/O APIC devices, but those present at boot were
+ * registered when we parsed the ACPI MADT.
+ */
+
+#define pr_fmt(fmt) "ACPI : IOAPIC: " fmt
+
+#include <linux/slab.h>
+#include <linux/acpi.h>
+#include <linux/pci.h>
+#include <acpi/acpi.h>
+
+struct acpi_pci_ioapic {
+ acpi_handle root_handle;
+ acpi_handle handle;
+ u32 gsi_base;
+ struct resource res;
+ struct pci_dev *pdev;
+ struct list_head list;
+};
+
+static LIST_HEAD(ioapic_list);
+static DEFINE_MUTEX(ioapic_list_lock);
+
+static acpi_status setup_res(struct acpi_resource *acpi_res, void *data)
+{
+ struct resource *res = data;
+
+ memset(res, 0, sizeof(*res));
+ if (acpi_dev_resource_memory(acpi_res, res)) {
+ res->flags &= IORESOURCE_MEM;
+ if (res->flags)
+ return AE_OK;
+ } else if (acpi_dev_resource_address_space(acpi_res, res)) {
+ struct acpi_resource_address64 addr;
+
+ res->flags &= IORESOURCE_MEM;
+ if (res->flags &&
+ ACPI_SUCCESS(acpi_resource_to_address64(acpi_res, &addr)) &&
+ addr.info.mem.caching != ACPI_PREFETCHABLE_MEMORY) {
+ res->start += addr.translation_offset;
+ res->end += addr.translation_offset;
+ return AE_OK;
+ }
+ }
+ res->flags = 0;
+
+ return AE_OK;
+}
+
+static bool acpi_is_ioapic(acpi_handle handle, char **type)
+{
+ acpi_status status;
+ struct acpi_device_info *info;
+ char *hid = NULL;
+ bool match = false;
+
+ if (!acpi_has_method(handle, "_GSB"))
+ return false;
+
+ status = acpi_get_object_info(handle, &info);
+ if (ACPI_SUCCESS(status)) {
+ if (info->valid & ACPI_VALID_HID)
+ hid = info->hardware_id.string;
+ if (hid) {
+ if (strcmp(hid, "ACPI0009") == 0) {
+ *type = "IOxAPIC";
+ match = true;
+ } else if (strcmp(hid, "ACPI000A") == 0) {
+ *type = "IOAPIC";
+ match = true;
+ }
+ }
+ kfree(info);
+ }
+
+ return match;
+}
+
+static acpi_status handle_ioapic_add(acpi_handle handle, u32 lvl,
+ void *context, void **rv)
+{
+ acpi_status status;
+ unsigned long long gsi_base;
+ struct acpi_pci_ioapic *ioapic;
+ struct pci_dev *dev = NULL;
+ struct resource *res = NULL;
+ char *type = NULL;
+
+ if (!acpi_is_ioapic(handle, &type))
+ return AE_OK;
+
+ mutex_lock(&ioapic_list_lock);
+ list_for_each_entry(ioapic, &ioapic_list, list)
+ if (ioapic->handle == handle) {
+ mutex_unlock(&ioapic_list_lock);
+ return AE_OK;
+ }
+
+ status = acpi_evaluate_integer(handle, "_GSB", NULL, &gsi_base);
+ if (ACPI_FAILURE(status)) {
+ acpi_handle_warn(handle, "failed to evaluate _GSB method\n");
+ goto exit;
+ }
+
+ ioapic = kzalloc(sizeof(*ioapic), GFP_KERNEL);
+ if (!ioapic) {
+ pr_err("cannot allocate memory for new IOAPIC\n");
+ goto exit;
+ } else {
+ ioapic->root_handle = (acpi_handle)context;
+ ioapic->handle = handle;
+ ioapic->gsi_base = (u32)gsi_base;
+ ioapic->res.flags = IORESOURCE_UNSET;
+ }
+
+ if (acpi_ioapic_registered(handle, (u32)gsi_base))
+ goto done;
+
+ dev = acpi_get_pci_dev(handle);
+ if (dev && pci_resource_len(dev, 0)) {
+ if (pci_enable_device(dev) < 0)
+ goto exit_put;
+ pci_set_master(dev);
+ if (pci_request_region(dev, 0, type))
+ goto exit_disable;
+ res = &dev->resource[0];
+ ioapic->pdev = dev;
+ } else {
+ pci_dev_put(dev);
+ dev = NULL;
+
+ res = &ioapic->res;
+ acpi_walk_resources(handle, METHOD_NAME__CRS, setup_res, res);
+ if (res->flags == IORESOURCE_UNSET) {
+ acpi_handle_warn(handle, "failed to get resource\n");
+ goto exit_free;
+ } else if (request_resource(&iomem_resource, res)) {
+ acpi_handle_warn(handle, "failed to insert resource\n");
+ goto exit_free;
+ }
+ }
+
+ if (acpi_register_ioapic(handle, res->start, (u32)gsi_base)) {
+ acpi_handle_warn(handle, "failed to register IOAPIC\n");
+ goto exit_release;
+ }
+done:
+ list_add(&ioapic->list, &ioapic_list);
+ mutex_unlock(&ioapic_list_lock);
+
+ if (dev)
+ dev_info(&dev->dev, "%s at %pR, GSI %u\n",
+ type, res, (u32)gsi_base);
+ else
+ acpi_handle_info(handle, "%s at %pR, GSI %u\n",
+ type, res, (u32)gsi_base);
+
+ return AE_OK;
+
+exit_release:
+ if (dev)
+ pci_release_region(dev, 0);
+ else
+ release_resource(res);
+exit_disable:
+ if (dev)
+ pci_disable_device(dev);
+exit_put:
+ if (dev)
+ pci_dev_put(dev);
+exit_free:
+ kfree(ioapic);
+exit:
+ mutex_unlock(&ioapic_list_lock);
+ *(acpi_status *)rv = AE_ERROR;
+ return AE_OK;
+}
+
+int acpi_ioapic_add(struct acpi_pci_root *root)
+{
+ acpi_status status, retval = AE_OK;
+
+ status = acpi_walk_namespace(ACPI_TYPE_DEVICE, root->device->handle,
+ UINT_MAX, handle_ioapic_add, NULL,
+ root->device->handle, (void **)&retval);
+
+ return ACPI_SUCCESS(status) && ACPI_SUCCESS(retval) ? 0 : -ENODEV;
+}
+
+int acpi_ioapic_remove(struct acpi_pci_root *root)
+{
+ int retval = 0;
+ struct acpi_pci_ioapic *ioapic, *tmp;
+
+ mutex_lock(&ioapic_list_lock);
+ list_for_each_entry_safe(ioapic, tmp, &ioapic_list, list) {
+ if (root->device->handle != ioapic->root_handle)
+ continue;
+
+ if (acpi_unregister_ioapic(ioapic->handle, ioapic->gsi_base))
+ retval = -EBUSY;
+
+ if (ioapic->pdev) {
+ pci_release_region(ioapic->pdev, 0);
+ pci_disable_device(ioapic->pdev);
+ pci_dev_put(ioapic->pdev);
+ } else if (ioapic->res.flags != IORESOURCE_UNSET) {
+ release_resource(&ioapic->res);
+ }
+ list_del(&ioapic->list);
+ kfree(ioapic);
+ }
+ mutex_unlock(&ioapic_list_lock);
+
+ return retval;
+}
diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c
index cd4de7e038ea..f3f77689bafc 100644
--- a/drivers/acpi/pci_root.c
+++ b/drivers/acpi/pci_root.c
@@ -614,6 +614,7 @@ static int acpi_pci_root_add(struct acpi_device *device,
if (system_state != SYSTEM_BOOTING) {
pcibios_resource_survey_bus(root->bus);
pci_assign_unassigned_root_bus_resources(root->bus);
+ acpi_ioapic_add(root);
}

pci_lock_rescan_remove();
@@ -634,6 +635,8 @@ static void acpi_pci_root_remove(struct acpi_device *device)

pci_stop_root_bus(root->bus);

+ WARN_ON(acpi_ioapic_remove(root));
+
device_set_run_wake(root->bus->bridge, false);
pci_acpi_remove_bus_pm_notifier(device);

--
1.7.10.4