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authorLinus Torvalds <torvalds@linux-foundation.org>2016-07-27 11:35:37 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2016-07-27 11:35:37 -0700
commit08fd8c17686c6b09fa410a26d516548dd80ff147 (patch)
tree0d8c17e70a94518a301e85fc7b23fbc09311068c /drivers/acpi/scan.c
parente831101a73fbc8339ef1d1909dad3ef64f089e70 (diff)
parentd34c30cc1fa80f509500ff192ea6bc7d30671061 (diff)
downloadlinux-08fd8c17686c6b09fa410a26d516548dd80ff147.tar.bz2
Merge tag 'for-linus-4.8-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen updates from David Vrabel: "Features and fixes for 4.8-rc0: - ACPI support for guests on ARM platforms. - Generic steal time support for arm and x86. - Support cases where kernel cpu is not Xen VCPU number (e.g., if in-guest kexec is used). - Use the system workqueue instead of a custom workqueue in various places" * tag 'for-linus-4.8-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (47 commits) xen: add static initialization of steal_clock op to xen_time_ops xen/pvhvm: run xen_vcpu_setup() for the boot CPU xen/evtchn: use xen_vcpu_id mapping xen/events: fifo: use xen_vcpu_id mapping xen/events: use xen_vcpu_id mapping in events_base x86/xen: use xen_vcpu_id mapping when pointing vcpu_info to shared_info x86/xen: use xen_vcpu_id mapping for HYPERVISOR_vcpu_op xen: introduce xen_vcpu_id mapping x86/acpi: store ACPI ids from MADT for future usage x86/xen: update cpuid.h from Xen-4.7 xen/evtchn: add IOCTL_EVTCHN_RESTRICT xen-blkback: really don't leak mode property xen-blkback: constify instance of "struct attribute_group" xen-blkfront: prefer xenbus_scanf() over xenbus_gather() xen-blkback: prefer xenbus_scanf() over xenbus_gather() xen: support runqueue steal time on xen arm/xen: add support for vm_assist hypercall xen: update xen headers xen-pciback: drop superfluous variables xen-pciback: short-circuit read path used for merging write values ...
Diffstat (limited to 'drivers/acpi/scan.c')
-rw-r--r--drivers/acpi/scan.c74
1 files changed, 74 insertions, 0 deletions
diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index 405056b95b05..ad9fc84a8601 100644
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -46,6 +46,13 @@ DEFINE_MUTEX(acpi_device_lock);
LIST_HEAD(acpi_wakeup_device_list);
static DEFINE_MUTEX(acpi_hp_context_lock);
+/*
+ * The UART device described by the SPCR table is the only object which needs
+ * special-casing. Everything else is covered by ACPI namespace paths in STAO
+ * table.
+ */
+static u64 spcr_uart_addr;
+
struct acpi_dep_data {
struct list_head node;
acpi_handle master;
@@ -1458,6 +1465,41 @@ static int acpi_add_single_object(struct acpi_device **child,
return 0;
}
+static acpi_status acpi_get_resource_memory(struct acpi_resource *ares,
+ void *context)
+{
+ struct resource *res = context;
+
+ if (acpi_dev_resource_memory(ares, res))
+ return AE_CTRL_TERMINATE;
+
+ return AE_OK;
+}
+
+static bool acpi_device_should_be_hidden(acpi_handle handle)
+{
+ acpi_status status;
+ struct resource res;
+
+ /* Check if it should ignore the UART device */
+ if (!(spcr_uart_addr && acpi_has_method(handle, METHOD_NAME__CRS)))
+ return false;
+
+ /*
+ * The UART device described in SPCR table is assumed to have only one
+ * memory resource present. So we only look for the first one here.
+ */
+ status = acpi_walk_resources(handle, METHOD_NAME__CRS,
+ acpi_get_resource_memory, &res);
+ if (ACPI_FAILURE(status) || res.start != spcr_uart_addr)
+ return false;
+
+ acpi_handle_info(handle, "The UART device @%pa in SPCR table will be hidden\n",
+ &res.start);
+
+ return true;
+}
+
static int acpi_bus_type_and_status(acpi_handle handle, int *type,
unsigned long long *sta)
{
@@ -1471,6 +1513,9 @@ static int acpi_bus_type_and_status(acpi_handle handle, int *type,
switch (acpi_type) {
case ACPI_TYPE_ANY: /* for ACPI_ROOT_OBJECT */
case ACPI_TYPE_DEVICE:
+ if (acpi_device_should_be_hidden(handle))
+ return -ENODEV;
+
*type = ACPI_BUS_TYPE_DEVICE;
status = acpi_bus_get_status_handle(handle, sta);
if (ACPI_FAILURE(status))
@@ -1925,11 +1970,26 @@ static int acpi_bus_scan_fixed(void)
return result < 0 ? result : 0;
}
+static void __init acpi_get_spcr_uart_addr(void)
+{
+ acpi_status status;
+ struct acpi_table_spcr *spcr_ptr;
+
+ status = acpi_get_table(ACPI_SIG_SPCR, 0,
+ (struct acpi_table_header **)&spcr_ptr);
+ if (ACPI_SUCCESS(status))
+ spcr_uart_addr = spcr_ptr->serial_port.address;
+ else
+ printk(KERN_WARNING PREFIX "STAO table present, but SPCR is missing\n");
+}
+
static bool acpi_scan_initialized;
int __init acpi_scan_init(void)
{
int result;
+ acpi_status status;
+ struct acpi_table_stao *stao_ptr;
acpi_pci_root_init();
acpi_pci_link_init();
@@ -1945,6 +2005,20 @@ int __init acpi_scan_init(void)
acpi_scan_add_handler(&generic_device_handler);
+ /*
+ * If there is STAO table, check whether it needs to ignore the UART
+ * device in SPCR table.
+ */
+ status = acpi_get_table(ACPI_SIG_STAO, 0,
+ (struct acpi_table_header **)&stao_ptr);
+ if (ACPI_SUCCESS(status)) {
+ if (stao_ptr->header.length > sizeof(struct acpi_table_stao))
+ printk(KERN_INFO PREFIX "STAO Name List not yet supported.");
+
+ if (stao_ptr->ignore_uart)
+ acpi_get_spcr_uart_addr();
+ }
+
mutex_lock(&acpi_scan_lock);
/*
* Enumerate devices in the ACPI namespace.