ACPICA: Add support for complex _PLD buffers.

_PLD (Physical Location of Device) returns a bit-packed buffer that
is difficult to parse. This change adds a new interface,
AcpiDecodePldBuffer that parses the buffer into a more usable
local struct. Also adds macros to both get and set individual
fields within the packed _PLD buffer. Adds a new include file,
acbuffer.h - which will be expanded to add structs for other
ACPI names that return buffers. ACPICA BZ 954.

Emit (in comments) the decoded contents of a static _PLD buffer
in order to improve comprehension of this bit-packed buffer.

Add multi-endian support to the _PLD decode routine. Deploy the
multi-endian macros to extract data from the _PLD buffer.

Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

7 files changed, 234 insertions, 12 deletions

diff --git a/include/acpi/acbuffer.h b/include/acpi/acbuffer.h
new file mode 100644
index 00000000000..2c3b44789f9
--- /dev/null
+++ b/include/acpi/acbuffer.h
@@ -0,0 +1,192 @@
+/******************************************************************************
+ *
+ * Name: acbuffer.h - Support for buffers returned by ACPI predefined names
+ *
+ *****************************************************************************/
+
+/*
+ * Copyright (C) 2000 - 2012, Intel Corp.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions, and the following disclaimer,
+ *    without modification.
+ * 2. Redistributions in binary form must reproduce at minimum a disclaimer
+ *    substantially similar to the "NO WARRANTY" disclaimer below
+ *    ("Disclaimer") and any redistribution must be conditioned upon
+ *    including a substantially similar Disclaimer requirement for further
+ *    binary redistribution.
+ * 3. Neither the names of the above-listed copyright holders nor the names
+ *    of any contributors may be used to endorse or promote products derived
+ *    from this software without specific prior written permission.
+ *
+ * Alternatively, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL") version 2 as published by the Free
+ * Software Foundation.
+ *
+ * NO WARRANTY
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+ * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGES.
+ */
+
+#ifndef __ACBUFFER_H__
+#define __ACBUFFER_H__
+
+/*
+ * Note: C bitfields are not used for this reason:
+ *
+ * "Bitfields are great and easy to read, but unfortunately the C language
+ * does not specify the layout of bitfields in memory, which means they are
+ * essentially useless for dealing with packed data in on-disk formats or
+ * binary wire protocols." (Or ACPI tables and buffers.) "If you ask me,
+ * this decision was a design error in C. Ritchie could have picked an order
+ * and stuck with it." Norman Ramsey.
+ * See http://stackoverflow.com/a/1053662/41661
+ */
+
+/*
+ * Formatted _PLD return value. The minimum size is a package containing
+ * one buffer.
+ * Revision 1: Buffer is 16 bytes (128 bits)
+ * Revision 2: Buffer is 20 bytes (160 bits)
+ *
+ * Note: This structure is returned from the acpi_decode_pld_buffer
+ * interface.
+ */
+struct acpi_pld_info {
+        u8 revision;
+        u8 ignore_color;
+        u32 color;
+        u16 width;
+        u16 height;
+        u8 user_visible;
+        u8 dock;
+        u8 lid;
+        u8 panel;
+        u8 vertical_position;
+        u8 horizontal_position;
+        u8 shape;
+        u8 group_orientation;
+        u8 group_token;
+        u8 group_position;
+        u8 bay;
+        u8 ejectable;
+        u8 ospm_eject_required;
+        u8 cabinet_number;
+        u8 card_cage_number;
+        u8 reference;
+        u8 rotation;
+        u8 order;
+        u8 reserved;
+        u16 vertical_offset;
+        u16 horizontal_offset;
+};
+
+/*
+ * Macros to:
+ *     1) Convert a _PLD buffer to internal struct acpi_pld_info format - ACPI_PLD_GET*
+ *        (Used by acpi_decode_pld_buffer)
+ *     2) Construct a _PLD buffer - ACPI_PLD_SET*
+ *        (Intended for BIOS use only)
+ */
+#define ACPI_PLD_REV1_BUFFER_SIZE               16      /* For Revision 1 of the buffer (From ACPI spec) */
+#define ACPI_PLD_BUFFER_SIZE                    20      /* For Revision 2 of the buffer (From ACPI spec) */
+
+/* First 32-bit dword, bits 0:32 */
+
+#define ACPI_PLD_GET_REVISION(dword)            ACPI_GET_BITS (dword, 0, ACPI_7BIT_MASK)
+#define ACPI_PLD_SET_REVISION(dword,value)      ACPI_SET_BITS (dword, 0, ACPI_7BIT_MASK, value) /* Offset 0, Len 7 */
+
+#define ACPI_PLD_GET_IGNORE_COLOR(dword)        ACPI_GET_BITS (dword, 7, ACPI_1BIT_MASK)
+#define ACPI_PLD_SET_IGNORE_COLOR(dword,value)  ACPI_SET_BITS (dword, 7, ACPI_1BIT_MASK, value) /* Offset 7, Len 1 */
+
+#define ACPI_PLD_GET_COLOR(dword)               ACPI_GET_BITS (dword, 8, ACPI_24BIT_MASK)
+#define ACPI_PLD_SET_COLOR(dword,value)         ACPI_SET_BITS (dword, 8, ACPI_24BIT_MASK, value)        /* Offset 8, Len 24 */
+
+/* Second 32-bit dword, bits 33:63 */
+
+#define ACPI_PLD_GET_WIDTH(dword)               ACPI_GET_BITS (dword, 0, ACPI_16BIT_MASK)
+#define ACPI_PLD_SET_WIDTH(dword,value)         ACPI_SET_BITS (dword, 0, ACPI_16BIT_MASK, value)        /* Offset 32+0=32, Len 16 */
+
+#define ACPI_PLD_GET_HEIGHT(dword)              ACPI_GET_BITS (dword, 16, ACPI_16BIT_MASK)
+#define ACPI_PLD_SET_HEIGHT(dword,value)        ACPI_SET_BITS (dword, 16, ACPI_16BIT_MASK, value)       /* Offset 32+16=48, Len 16 */
+
+/* Third 32-bit dword, bits 64:95 */
+
+#define ACPI_PLD_GET_USER_VISIBLE(dword)        ACPI_GET_BITS (dword, 0, ACPI_1BIT_MASK)
+#define ACPI_PLD_SET_USER_VISIBLE(dword,value)  ACPI_SET_BITS (dword, 0, ACPI_1BIT_MASK, value) /* Offset 64+0=64, Len 1 */
+
+#define ACPI_PLD_GET_DOCK(dword)                ACPI_GET_BITS (dword, 1, ACPI_1BIT_MASK)
+#define ACPI_PLD_SET_DOCK(dword,value)          ACPI_SET_BITS (dword, 1, ACPI_1BIT_MASK, value) /* Offset 64+1=65, Len 1 */
+
+#define ACPI_PLD_GET_LID(dword)                 ACPI_GET_BITS (dword, 2, ACPI_1BIT_MASK)
+#define ACPI_PLD_SET_LID(dword,value)           ACPI_SET_BITS (dword, 2, ACPI_1BIT_MASK, value) /* Offset 64+2=66, Len 1 */
+
+#define ACPI_PLD_GET_PANEL(dword)               ACPI_GET_BITS (dword, 3, ACPI_3BIT_MASK)
+#define ACPI_PLD_SET_PANEL(dword,value)         ACPI_SET_BITS (dword, 3, ACPI_3BIT_MASK, value) /* Offset 64+3=67, Len 3 */
+
+#define ACPI_PLD_GET_VERTICAL(dword)            ACPI_GET_BITS (dword, 6, ACPI_2BIT_MASK)
+#define ACPI_PLD_SET_VERTICAL(dword,value)      ACPI_SET_BITS (dword, 6, ACPI_2BIT_MASK, value) /* Offset 64+6=70, Len 2 */
+
+#define ACPI_PLD_GET_HORIZONTAL(dword)          ACPI_GET_BITS (dword, 8, ACPI_2BIT_MASK)
+#define ACPI_PLD_SET_HORIZONTAL(dword,value)    ACPI_SET_BITS (dword, 8, ACPI_2BIT_MASK, value) /* Offset 64+8=72, Len 2 */
+
+#define ACPI_PLD_GET_SHAPE(dword)               ACPI_GET_BITS (dword, 10, ACPI_4BIT_MASK)
+#define ACPI_PLD_SET_SHAPE(dword,value)         ACPI_SET_BITS (dword, 10, ACPI_4BIT_MASK, value)        /* Offset 64+10=74, Len 4 */
+
+#define ACPI_PLD_GET_ORIENTATION(dword)         ACPI_GET_BITS (dword, 14, ACPI_1BIT_MASK)
+#define ACPI_PLD_SET_ORIENTATION(dword,value)   ACPI_SET_BITS (dword, 14, ACPI_1BIT_MASK, value)        /* Offset 64+14=78, Len 1 */
+
+#define ACPI_PLD_GET_TOKEN(dword)               ACPI_GET_BITS (dword, 15, ACPI_8BIT_MASK)
+#define ACPI_PLD_SET_TOKEN(dword,value)         ACPI_SET_BITS (dword, 15, ACPI_8BIT_MASK, value)        /* Offset 64+15=79, Len 8 */
+
+#define ACPI_PLD_GET_POSITION(dword)            ACPI_GET_BITS (dword, 23, ACPI_8BIT_MASK)
+#define ACPI_PLD_SET_POSITION(dword,value)      ACPI_SET_BITS (dword, 23, ACPI_8BIT_MASK, value)        /* Offset 64+23=87, Len 8 */
+
+#define ACPI_PLD_GET_BAY(dword)                 ACPI_GET_BITS (dword, 31, ACPI_1BIT_MASK)
+#define ACPI_PLD_SET_BAY(dword,value)           ACPI_SET_BITS (dword, 31, ACPI_1BIT_MASK, value)        /* Offset 64+31=95, Len 1 */
+
+/* Fourth 32-bit dword, bits 96:127 */
+
+#define ACPI_PLD_GET_EJECTABLE(dword)           ACPI_GET_BITS (dword, 0, ACPI_1BIT_MASK)
+#define ACPI_PLD_SET_EJECTABLE(dword,value)     ACPI_SET_BITS (dword, 0, ACPI_1BIT_MASK, value) /* Offset 96+0=96, Len 1 */
+
+#define ACPI_PLD_GET_OSPM_EJECT(dword)          ACPI_GET_BITS (dword, 1, ACPI_1BIT_MASK)
+#define ACPI_PLD_SET_OSPM_EJECT(dword,value)    ACPI_SET_BITS (dword, 1, ACPI_1BIT_MASK, value) /* Offset 96+1=97, Len 1 */
+
+#define ACPI_PLD_GET_CABINET(dword)             ACPI_GET_BITS (dword, 2, ACPI_8BIT_MASK)
+#define ACPI_PLD_SET_CABINET(dword,value)       ACPI_SET_BITS (dword, 2, ACPI_8BIT_MASK, value) /* Offset 96+2=98, Len 8 */
+
+#define ACPI_PLD_GET_CARD_CAGE(dword)           ACPI_GET_BITS (dword, 10, ACPI_8BIT_MASK)
+#define ACPI_PLD_SET_CARD_CAGE(dword,value)     ACPI_SET_BITS (dword, 10, ACPI_8BIT_MASK, value)        /* Offset 96+10=106, Len 8 */
+
+#define ACPI_PLD_GET_REFERENCE(dword)           ACPI_GET_BITS (dword, 18, ACPI_1BIT_MASK)
+#define ACPI_PLD_SET_REFERENCE(dword,value)     ACPI_SET_BITS (dword, 18, ACPI_1BIT_MASK, value)        /* Offset 96+18=114, Len 1 */
+
+#define ACPI_PLD_GET_ROTATION(dword)            ACPI_GET_BITS (dword, 19, ACPI_4BIT_MASK)
+#define ACPI_PLD_SET_ROTATION(dword,value)      ACPI_SET_BITS (dword, 19, ACPI_4BIT_MASK, value)        /* Offset 96+19=115, Len 4 */
+
+#define ACPI_PLD_GET_ORDER(dword)               ACPI_GET_BITS (dword, 23, ACPI_5BIT_MASK)
+#define ACPI_PLD_SET_ORDER(dword,value)         ACPI_SET_BITS (dword, 23, ACPI_5BIT_MASK, value)        /* Offset 96+23=119, Len 5 */
+
+/* Fifth 32-bit dword, bits 128:159 (Revision 2 of _PLD only) */
+
+#define ACPI_PLD_GET_VERT_OFFSET(dword)         ACPI_GET_BITS (dword, 0, ACPI_16BIT_MASK)
+#define ACPI_PLD_SET_VERT_OFFSET(dword,value)   ACPI_SET_BITS (dword, 0, ACPI_16BIT_MASK, value)        /* Offset 128+0=128, Len 16 */
+
+#define ACPI_PLD_GET_HORIZ_OFFSET(dword)        ACPI_GET_BITS (dword, 16, ACPI_16BIT_MASK)
+#define ACPI_PLD_SET_HORIZ_OFFSET(dword,value)  ACPI_SET_BITS (dword, 16, ACPI_16BIT_MASK, value)       /* Offset 128+16=144, Len 16 */
+
+#endif                          /* ACBUFFER_H */
diff --git a/include/acpi/acnames.h b/include/acpi/acnames.h
index d2f61dd2d72..745dd24e3cb 100644
--- a/include/acpi/acnames.h
+++ b/include/acpi/acnames.h
@@ -63,6 +63,7 @@
 #define METHOD_NAME__PRW        "_PRW"
 #define METHOD_NAME__SRS        "_SRS"
 #define METHOD_NAME__CBA        "_CBA"
+#define METHOD_NAME__PLD        "_PLD"
 
 /* Method names - these methods must appear at the namespace root */
 
diff --git a/include/acpi/acpixf.h b/include/acpi/acpixf.h
index 26a92fc28a5..270517d6b1b 100644
--- a/include/acpi/acpixf.h
+++ b/include/acpi/acpixf.h
@@ -52,6 +52,7 @@
 #include "acconfig.h"
 #include "actypes.h"
 #include "actbl.h"
+#include "acbuffer.h"
 
 extern u8 acpi_gbl_permanent_mmap;
 
@@ -144,6 +145,10 @@ acpi_check_address_range(acpi_adr_space_type space_id,
                          acpi_physical_address address,
                          acpi_size length, u8 warn);
 
+acpi_status
+acpi_decode_pld_buffer(u8 *in_buffer,
+                       acpi_size length, struct acpi_pld_info **return_buffer);
+
 /*
  * ACPI Memory management
  */
diff --git a/include/acpi/actbl.h b/include/acpi/actbl.h
index d54e3580b7d..4f94b1d812d 100644
--- a/include/acpi/actbl.h
+++ b/include/acpi/actbl.h
@@ -79,9 +79,15 @@
 #pragma pack(1)
 
 /*
- * Note about bitfields: The u8 type is used for bitfields in ACPI tables.
- * This is the only type that is even remotely portable. Anything else is not
- * portable, so do not use any other bitfield types.
+ * Note: C bitfields are not used for this reason:
+ *
+ * "Bitfields are great and easy to read, but unfortunately the C language
+ * does not specify the layout of bitfields in memory, which means they are
+ * essentially useless for dealing with packed data in on-disk formats or
+ * binary wire protocols." (Or ACPI tables and buffers.) "If you ask me,
+ * this decision was a design error in C. Ritchie could have picked an order
+ * and stuck with it." Norman Ramsey.
+ * See http://stackoverflow.com/a/1053662/41661
  */
 
 /*******************************************************************************
diff --git a/include/acpi/actbl1.h b/include/acpi/actbl1.h
index 300d14e7c5d..c41d6f96ed7 100644
--- a/include/acpi/actbl1.h
+++ b/include/acpi/actbl1.h
@@ -79,9 +79,15 @@
 #pragma pack(1)
 
 /*
- * Note about bitfields: The u8 type is used for bitfields in ACPI tables.
- * This is the only type that is even remotely portable. Anything else is not
- * portable, so do not use any other bitfield types.
+ * Note: C bitfields are not used for this reason:
+ *
+ * "Bitfields are great and easy to read, but unfortunately the C language
+ * does not specify the layout of bitfields in memory, which means they are
+ * essentially useless for dealing with packed data in on-disk formats or
+ * binary wire protocols." (Or ACPI tables and buffers.) "If you ask me,
+ * this decision was a design error in C. Ritchie could have picked an order
+ * and stuck with it." Norman Ramsey.
+ * See http://stackoverflow.com/a/1053662/41661
  */
 
 /*******************************************************************************
diff --git a/include/acpi/actbl2.h b/include/acpi/actbl2.h
index b74476c0be8..1b2b356486d 100644
--- a/include/acpi/actbl2.h
+++ b/include/acpi/actbl2.h
@@ -98,9 +98,15 @@
 #pragma pack(1)
 
 /*
- * Note about bitfields: The u8 type is used for bitfields in ACPI tables.
- * This is the only type that is even remotely portable. Anything else is not
- * portable, so do not use any other bitfield types.
+ * Note: C bitfields are not used for this reason:
+ *
+ * "Bitfields are great and easy to read, but unfortunately the C language
+ * does not specify the layout of bitfields in memory, which means they are
+ * essentially useless for dealing with packed data in on-disk formats or
+ * binary wire protocols." (Or ACPI tables and buffers.) "If you ask me,
+ * this decision was a design error in C. Ritchie could have picked an order
+ * and stuck with it." Norman Ramsey.
+ * See http://stackoverflow.com/a/1053662/41661
  */
 
 /*******************************************************************************
diff --git a/include/acpi/actbl3.h b/include/acpi/actbl3.h
index 37781ab806a..8c61b5fe42a 100644
--- a/include/acpi/actbl3.h
+++ b/include/acpi/actbl3.h
@@ -86,9 +86,15 @@
 #pragma pack(1)
 
 /*
- * Note about bitfields: The u8 type is used for bitfields in ACPI tables.
- * This is the only type that is even remotely portable. Anything else is not
- * portable, so do not use any other bitfield types.
+ * Note: C bitfields are not used for this reason:
+ *
+ * "Bitfields are great and easy to read, but unfortunately the C language
+ * does not specify the layout of bitfields in memory, which means they are
+ * essentially useless for dealing with packed data in on-disk formats or
+ * binary wire protocols." (Or ACPI tables and buffers.) "If you ask me,
+ * this decision was a design error in C. Ritchie could have picked an order
+ * and stuck with it." Norman Ramsey.
+ * See http://stackoverflow.com/a/1053662/41661
  */
 
 /*******************************************************************************