From bc9ffce27962c0c5fdc6adf74790ea0fcbe4a99c Mon Sep 17 00:00:00 2001
From: Myron Stowe <mstowe@redhat.com>
Date: Mon, 7 Nov 2011 16:23:27 -0700
Subject: ACPI: Fix possible alignment issues with GAS 'address' references

Generic Address Structures (GAS) may reside within ACPI tables which
are byte aligned.  This patch copies GAS 'address' references to a local
variable, which will be naturally aligned, to be used going forward.

ACPI Generic Address Structure (GAS) reference:
  ACPI Specification, Revision 4.0, Section 5.2.3.1, "Generic Address
  Structure"

Signed-off-by: Myron Stowe <myron.stowe@redhat.com>
Signed-off-by: Len Brown <len.brown@intel.com>
---
 drivers/acpi/osl.c | 38 ++++++++++++++++++++++++--------------
 1 file changed, 24 insertions(+), 14 deletions(-)

(limited to 'drivers/acpi/osl.c')

diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
index f31c5c5f1b7e..2e285cdbefb1 100644
--- a/drivers/acpi/osl.c
+++ b/drivers/acpi/osl.c
@@ -166,17 +166,21 @@ static u32 acpi_osi_handler(acpi_string interface, u32 supported)
 	return supported;
 }
 
-static void __init acpi_request_region (struct acpi_generic_address *addr,
+static void __init acpi_request_region (struct acpi_generic_address *gas,
 	unsigned int length, char *desc)
 {
-	if (!addr->address || !length)
+	u64 addr;
+
+	/* Handle possible alignment issues */
+	memcpy(&addr, &gas->address, sizeof(addr));
+	if (!addr || !length)
 		return;
 
 	/* Resources are never freed */
-	if (addr->space_id == ACPI_ADR_SPACE_SYSTEM_IO)
-		request_region(addr->address, length, desc);
-	else if (addr->space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY)
-		request_mem_region(addr->address, length, desc);
+	if (gas->space_id == ACPI_ADR_SPACE_SYSTEM_IO)
+		request_region(addr, length, desc);
+	else if (gas->space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY)
+		request_mem_region(addr, length, desc);
 }
 
 static int __init acpi_reserve_resources(void)
@@ -427,35 +431,41 @@ void __init early_acpi_os_unmap_memory(void __iomem *virt, acpi_size size)
 		__acpi_unmap_table(virt, size);
 }
 
-static int acpi_os_map_generic_address(struct acpi_generic_address *addr)
+static int acpi_os_map_generic_address(struct acpi_generic_address *gas)
 {
+	u64 addr;
 	void __iomem *virt;
 
-	if (addr->space_id != ACPI_ADR_SPACE_SYSTEM_MEMORY)
+	if (gas->space_id != ACPI_ADR_SPACE_SYSTEM_MEMORY)
 		return 0;
 
-	if (!addr->address || !addr->bit_width)
+	/* Handle possible alignment issues */
+	memcpy(&addr, &gas->address, sizeof(addr));
+	if (!addr || !gas->bit_width)
 		return -EINVAL;
 
-	virt = acpi_os_map_memory(addr->address, addr->bit_width / 8);
+	virt = acpi_os_map_memory(addr, gas->bit_width / 8);
 	if (!virt)
 		return -EIO;
 
 	return 0;
 }
 
-static void acpi_os_unmap_generic_address(struct acpi_generic_address *addr)
+static void acpi_os_unmap_generic_address(struct acpi_generic_address *gas)
 {
+	u64 addr;
 	struct acpi_ioremap *map;
 
-	if (addr->space_id != ACPI_ADR_SPACE_SYSTEM_MEMORY)
+	if (gas->space_id != ACPI_ADR_SPACE_SYSTEM_MEMORY)
 		return;
 
-	if (!addr->address || !addr->bit_width)
+	/* Handle possible alignment issues */
+	memcpy(&addr, &gas->address, sizeof(addr));
+	if (!addr || !gas->bit_width)
 		return;
 
 	mutex_lock(&acpi_ioremap_lock);
-	map = acpi_map_lookup(addr->address, addr->bit_width / 8);
+	map = acpi_map_lookup(addr, gas->bit_width / 8);
 	if (!map) {
 		mutex_unlock(&acpi_ioremap_lock);
 		return;
-- 
cgit v1.2.3


From 6f68c91c55ea3576d366797fa8d45e31c4aa79f8 Mon Sep 17 00:00:00 2001
From: Myron Stowe <mstowe@redhat.com>
Date: Mon, 7 Nov 2011 16:23:34 -0700
Subject: ACPI: Export interfaces for ioremapping/iounmapping ACPI registers

Export remapping and unmapping interfaces - acpi_os_map_generic_address()
and acpi_os_unmap_generic_address() - for ACPI generic registers that are
backed by memory mapped I/O (MMIO).

The acpi_os_map_generic_address() and acpi_os_unmap_generic_address()
declarations may more properly belong in include/acpi/acpiosxf.h next to
acpi_os_read_memory() but I believe that would require the ACPI CA making
them an official part of the ACPI CA - OS interface.

ACPI Generic Address Structure (GAS) reference (ACPI's fixed/generic
hardware registers use the GAS format):
  ACPI Specification, Revision 4.0, Section 5.2.3.1, "Generic Address
  Structure"

Signed-off-by: Myron Stowe <myron.stowe@redhat.com>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>
---
 drivers/acpi/osl.c      | 6 ++++--
 include/linux/acpi_io.h | 3 +++
 2 files changed, 7 insertions(+), 2 deletions(-)

(limited to 'drivers/acpi/osl.c')

diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
index 2e285cdbefb1..b11f2676f7c9 100644
--- a/drivers/acpi/osl.c
+++ b/drivers/acpi/osl.c
@@ -431,7 +431,7 @@ void __init early_acpi_os_unmap_memory(void __iomem *virt, acpi_size size)
 		__acpi_unmap_table(virt, size);
 }
 
-static int acpi_os_map_generic_address(struct acpi_generic_address *gas)
+int acpi_os_map_generic_address(struct acpi_generic_address *gas)
 {
 	u64 addr;
 	void __iomem *virt;
@@ -450,8 +450,9 @@ static int acpi_os_map_generic_address(struct acpi_generic_address *gas)
 
 	return 0;
 }
+EXPORT_SYMBOL(acpi_os_map_generic_address);
 
-static void acpi_os_unmap_generic_address(struct acpi_generic_address *gas)
+void acpi_os_unmap_generic_address(struct acpi_generic_address *gas)
 {
 	u64 addr;
 	struct acpi_ioremap *map;
@@ -475,6 +476,7 @@ static void acpi_os_unmap_generic_address(struct acpi_generic_address *gas)
 
 	acpi_os_map_cleanup(map);
 }
+EXPORT_SYMBOL(acpi_os_unmap_generic_address);
 
 #ifdef ACPI_FUTURE_USAGE
 acpi_status
diff --git a/include/linux/acpi_io.h b/include/linux/acpi_io.h
index 4afd7102459d..b0ffa219993e 100644
--- a/include/linux/acpi_io.h
+++ b/include/linux/acpi_io.h
@@ -12,4 +12,7 @@ static inline void __iomem *acpi_os_ioremap(acpi_physical_address phys,
 
 void __iomem *acpi_os_get_iomem(acpi_physical_address phys, unsigned int size);
 
+int acpi_os_map_generic_address(struct acpi_generic_address *addr);
+void acpi_os_unmap_generic_address(struct acpi_generic_address *addr);
+
 #endif
-- 
cgit v1.2.3