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-rw-r--r--Documentation/ABI/testing/ima_policy3
-rw-r--r--Documentation/devicetree/bindings/arm/davinci/nand.txt8
-rw-r--r--Documentation/devicetree/bindings/mtd/denali-nand.txt23
-rw-r--r--Documentation/devicetree/bindings/mtd/flctl-nand.txt49
-rw-r--r--Documentation/devicetree/bindings/mtd/fsmc-nand.txt12
-rw-r--r--Documentation/devicetree/bindings/mtd/m25p80.txt29
-rw-r--r--Documentation/devicetree/bindings/mtd/mtd-physmap.txt3
-rw-r--r--Documentation/devicetree/bindings/pwm/pwm-tiecap.txt23
-rw-r--r--Documentation/devicetree/bindings/pwm/pwm-tiehrpwm.txt23
-rw-r--r--Documentation/devicetree/bindings/pwm/pwm-tipwmss.txt31
-rw-r--r--Documentation/devicetree/bindings/pwm/pwm.txt17
-rw-r--r--Documentation/devicetree/bindings/pwm/spear-pwm.txt18
-rw-r--r--Documentation/devicetree/bindings/pwm/ti,twl-pwm.txt17
-rw-r--r--Documentation/devicetree/bindings/pwm/ti,twl-pwmled.txt17
-rw-r--r--Documentation/devicetree/bindings/pwm/vt8500-pwm.txt17
-rw-r--r--Documentation/devicetree/bindings/spi/nvidia,tegra20-sflash.txt2
-rw-r--r--Documentation/devicetree/bindings/spi/nvidia,tegra20-slink.txt2
-rw-r--r--Documentation/devicetree/bindings/spi/spi_atmel.txt26
-rw-r--r--Documentation/x86/boot.txt3
-rw-r--r--Documentation/xtensa/atomctl.txt44
20 files changed, 353 insertions, 14 deletions
diff --git a/Documentation/ABI/testing/ima_policy b/Documentation/ABI/testing/ima_policy
index 98694661354..ec0a38ef314 100644
--- a/Documentation/ABI/testing/ima_policy
+++ b/Documentation/ABI/testing/ima_policy
@@ -23,7 +23,7 @@ Description:
lsm: [[subj_user=] [subj_role=] [subj_type=]
[obj_user=] [obj_role=] [obj_type=]]
- base: func:= [BPRM_CHECK][FILE_MMAP][FILE_CHECK]
+ base: func:= [BPRM_CHECK][FILE_MMAP][FILE_CHECK][MODULE_CHECK]
mask:= [MAY_READ] [MAY_WRITE] [MAY_APPEND] [MAY_EXEC]
fsmagic:= hex value
uid:= decimal value
@@ -53,6 +53,7 @@ Description:
measure func=BPRM_CHECK
measure func=FILE_MMAP mask=MAY_EXEC
measure func=FILE_CHECK mask=MAY_READ uid=0
+ measure func=MODULE_CHECK uid=0
appraise fowner=0
The default policy measures all executables in bprm_check,
diff --git a/Documentation/devicetree/bindings/arm/davinci/nand.txt b/Documentation/devicetree/bindings/arm/davinci/nand.txt
index 49fc7ada929..3545ea704b5 100644
--- a/Documentation/devicetree/bindings/arm/davinci/nand.txt
+++ b/Documentation/devicetree/bindings/arm/davinci/nand.txt
@@ -23,6 +23,9 @@ Recommended properties :
- ti,davinci-nand-buswidth: buswidth 8 or 16
- ti,davinci-nand-use-bbt: use flash based bad block table support.
+nand device bindings may contain additional sub-nodes describing
+partitions of the address space. See partition.txt for more detail.
+
Example(da850 EVM ):
nand_cs3@62000000 {
compatible = "ti,davinci-nand";
@@ -35,4 +38,9 @@ nand_cs3@62000000 {
ti,davinci-ecc-mode = "hw";
ti,davinci-ecc-bits = <4>;
ti,davinci-nand-use-bbt;
+
+ partition@180000 {
+ label = "ubifs";
+ reg = <0x180000 0x7e80000>;
+ };
};
diff --git a/Documentation/devicetree/bindings/mtd/denali-nand.txt b/Documentation/devicetree/bindings/mtd/denali-nand.txt
new file mode 100644
index 00000000000..b04d03a1d49
--- /dev/null
+++ b/Documentation/devicetree/bindings/mtd/denali-nand.txt
@@ -0,0 +1,23 @@
+* Denali NAND controller
+
+Required properties:
+ - compatible : should be "denali,denali-nand-dt"
+ - reg : should contain registers location and length for data and reg.
+ - reg-names: Should contain the reg names "nand_data" and "denali_reg"
+ - interrupts : The interrupt number.
+ - dm-mask : DMA bit mask
+
+The device tree may optionally contain sub-nodes describing partitions of the
+address space. See partition.txt for more detail.
+
+Examples:
+
+nand: nand@ff900000 {
+ #address-cells = <1>;
+ #size-cells = <1>;
+ compatible = "denali,denali-nand-dt";
+ reg = <0xff900000 0x100000>, <0xffb80000 0x10000>;
+ reg-names = "nand_data", "denali_reg";
+ interrupts = <0 144 4>;
+ dma-mask = <0xffffffff>;
+};
diff --git a/Documentation/devicetree/bindings/mtd/flctl-nand.txt b/Documentation/devicetree/bindings/mtd/flctl-nand.txt
new file mode 100644
index 00000000000..427f46dc60a
--- /dev/null
+++ b/Documentation/devicetree/bindings/mtd/flctl-nand.txt
@@ -0,0 +1,49 @@
+FLCTL NAND controller
+
+Required properties:
+- compatible : "renesas,shmobile-flctl-sh7372"
+- reg : Address range of the FLCTL
+- interrupts : flste IRQ number
+- nand-bus-width : bus width to NAND chip
+
+Optional properties:
+- dmas: DMA specifier(s)
+- dma-names: name for each DMA specifier. Valid names are
+ "data_tx", "data_rx", "ecc_tx", "ecc_rx"
+
+The DMA fields are not used yet in the driver but are listed here for
+completing the bindings.
+
+The device tree may optionally contain sub-nodes describing partitions of the
+address space. See partition.txt for more detail.
+
+Example:
+
+ flctl@e6a30000 {
+ #address-cells = <1>;
+ #size-cells = <1>;
+ compatible = "renesas,shmobile-flctl-sh7372";
+ reg = <0xe6a30000 0x100>;
+ interrupts = <0x0d80>;
+
+ nand-bus-width = <16>;
+
+ dmas = <&dmac 1 /* data_tx */
+ &dmac 2;> /* data_rx */
+ dma-names = "data_tx", "data_rx";
+
+ system@0 {
+ label = "system";
+ reg = <0x0 0x8000000>;
+ };
+
+ userdata@8000000 {
+ label = "userdata";
+ reg = <0x8000000 0x10000000>;
+ };
+
+ cache@18000000 {
+ label = "cache";
+ reg = <0x18000000 0x8000000>;
+ };
+ };
diff --git a/Documentation/devicetree/bindings/mtd/fsmc-nand.txt b/Documentation/devicetree/bindings/mtd/fsmc-nand.txt
index e2c663b354d..e3ea32e7de3 100644
--- a/Documentation/devicetree/bindings/mtd/fsmc-nand.txt
+++ b/Documentation/devicetree/bindings/mtd/fsmc-nand.txt
@@ -3,9 +3,7 @@
Required properties:
- compatible : "st,spear600-fsmc-nand"
- reg : Address range of the mtd chip
-- reg-names: Should contain the reg names "fsmc_regs" and "nand_data"
-- st,ale-off : Chip specific offset to ALE
-- st,cle-off : Chip specific offset to CLE
+- reg-names: Should contain the reg names "fsmc_regs", "nand_data", "nand_addr" and "nand_cmd"
Optional properties:
- bank-width : Width (in bytes) of the device. If not present, the width
@@ -19,10 +17,10 @@ Example:
#address-cells = <1>;
#size-cells = <1>;
reg = <0xd1800000 0x1000 /* FSMC Register */
- 0xd2000000 0x4000>; /* NAND Base */
- reg-names = "fsmc_regs", "nand_data";
- st,ale-off = <0x20000>;
- st,cle-off = <0x10000>;
+ 0xd2000000 0x0010 /* NAND Base DATA */
+ 0xd2020000 0x0010 /* NAND Base ADDR */
+ 0xd2010000 0x0010>; /* NAND Base CMD */
+ reg-names = "fsmc_regs", "nand_data", "nand_addr", "nand_cmd";
bank-width = <1>;
nand-skip-bbtscan;
diff --git a/Documentation/devicetree/bindings/mtd/m25p80.txt b/Documentation/devicetree/bindings/mtd/m25p80.txt
new file mode 100644
index 00000000000..6d3d5760947
--- /dev/null
+++ b/Documentation/devicetree/bindings/mtd/m25p80.txt
@@ -0,0 +1,29 @@
+* MTD SPI driver for ST M25Pxx (and similar) serial flash chips
+
+Required properties:
+- #address-cells, #size-cells : Must be present if the device has sub-nodes
+ representing partitions.
+- compatible : Should be the manufacturer and the name of the chip. Bear in mind
+ the DT binding is not Linux-only, but in case of Linux, see the
+ "m25p_ids" table in drivers/mtd/devices/m25p80.c for the list of
+ supported chips.
+- reg : Chip-Select number
+- spi-max-frequency : Maximum frequency of the SPI bus the chip can operate at
+
+Optional properties:
+- m25p,fast-read : Use the "fast read" opcode to read data from the chip instead
+ of the usual "read" opcode. This opcode is not supported by
+ all chips and support for it can not be detected at runtime.
+ Refer to your chips' datasheet to check if this is supported
+ by your chip.
+
+Example:
+
+ flash: m25p80@0 {
+ #address-cells = <1>;
+ #size-cells = <1>;
+ compatible = "spansion,m25p80";
+ reg = <0>;
+ spi-max-frequency = <40000000>;
+ m25p,fast-read;
+ };
diff --git a/Documentation/devicetree/bindings/mtd/mtd-physmap.txt b/Documentation/devicetree/bindings/mtd/mtd-physmap.txt
index 94de19b8f16..dab7847fc80 100644
--- a/Documentation/devicetree/bindings/mtd/mtd-physmap.txt
+++ b/Documentation/devicetree/bindings/mtd/mtd-physmap.txt
@@ -23,6 +23,9 @@ file systems on embedded devices.
unaligned accesses as implemented in the JFFS2 code via memcpy().
By defining "no-unaligned-direct-access", the flash will not be
exposed directly to the MTD users (e.g. JFFS2) any more.
+ - linux,mtd-name: allow to specify the mtd name for retro capability with
+ physmap-flash drivers as boot loader pass the mtd partition via the old
+ device name physmap-flash.
For JEDEC compatible devices, the following additional properties
are defined:
diff --git a/Documentation/devicetree/bindings/pwm/pwm-tiecap.txt b/Documentation/devicetree/bindings/pwm/pwm-tiecap.txt
new file mode 100644
index 00000000000..131e8c11d26
--- /dev/null
+++ b/Documentation/devicetree/bindings/pwm/pwm-tiecap.txt
@@ -0,0 +1,23 @@
+TI SOC ECAP based APWM controller
+
+Required properties:
+- compatible: Must be "ti,am33xx-ecap"
+- #pwm-cells: Should be 3. Number of cells being used to specify PWM property.
+ First cell specifies the per-chip index of the PWM to use, the second
+ cell is the period in nanoseconds and bit 0 in the third cell is used to
+ encode the polarity of PWM output. Set bit 0 of the third in PWM specifier
+ to 1 for inverse polarity & set to 0 for normal polarity.
+- reg: physical base address and size of the registers map.
+
+Optional properties:
+- ti,hwmods: Name of the hwmod associated to the ECAP:
+ "ecap<x>", <x> being the 0-based instance number from the HW spec
+
+Example:
+
+ecap0: ecap@0 {
+ compatible = "ti,am33xx-ecap";
+ #pwm-cells = <3>;
+ reg = <0x48300100 0x80>;
+ ti,hwmods = "ecap0";
+};
diff --git a/Documentation/devicetree/bindings/pwm/pwm-tiehrpwm.txt b/Documentation/devicetree/bindings/pwm/pwm-tiehrpwm.txt
new file mode 100644
index 00000000000..4fc7079d822
--- /dev/null
+++ b/Documentation/devicetree/bindings/pwm/pwm-tiehrpwm.txt
@@ -0,0 +1,23 @@
+TI SOC EHRPWM based PWM controller
+
+Required properties:
+- compatible : Must be "ti,am33xx-ehrpwm"
+- #pwm-cells: Should be 3. Number of cells being used to specify PWM property.
+ First cell specifies the per-chip index of the PWM to use, the second
+ cell is the period in nanoseconds and bit 0 in the third cell is used to
+ encode the polarity of PWM output. Set bit 0 of the third in PWM specifier
+ to 1 for inverse polarity & set to 0 for normal polarity.
+- reg: physical base address and size of the registers map.
+
+Optional properties:
+- ti,hwmods: Name of the hwmod associated to the EHRPWM:
+ "ehrpwm<x>", <x> being the 0-based instance number from the HW spec
+
+Example:
+
+ehrpwm0: ehrpwm@0 {
+ compatible = "ti,am33xx-ehrpwm";
+ #pwm-cells = <3>;
+ reg = <0x48300200 0x100>;
+ ti,hwmods = "ehrpwm0";
+};
diff --git a/Documentation/devicetree/bindings/pwm/pwm-tipwmss.txt b/Documentation/devicetree/bindings/pwm/pwm-tipwmss.txt
new file mode 100644
index 00000000000..f7eae77f835
--- /dev/null
+++ b/Documentation/devicetree/bindings/pwm/pwm-tipwmss.txt
@@ -0,0 +1,31 @@
+TI SOC based PWM Subsystem
+
+Required properties:
+- compatible: Must be "ti,am33xx-pwmss";
+- reg: physical base address and size of the registers map.
+- address-cells: Specify the number of u32 entries needed in child nodes.
+ Should set to 1.
+- size-cells: specify number of u32 entries needed to specify child nodes size
+ in reg property. Should set to 1.
+- ranges: describes the address mapping of a memory-mapped bus. Should set to
+ physical address map of child's base address, physical address within
+ parent's address space and length of the address map. For am33xx,
+ 3 set of child register maps present, ECAP register space, EQEP
+ register space, EHRPWM register space.
+
+Also child nodes should also populated under PWMSS DT node.
+
+Example:
+pwmss0: pwmss@48300000 {
+ compatible = "ti,am33xx-pwmss";
+ reg = <0x48300000 0x10>;
+ ti,hwmods = "epwmss0";
+ #address-cells = <1>;
+ #size-cells = <1>;
+ status = "disabled";
+ ranges = <0x48300100 0x48300100 0x80 /* ECAP */
+ 0x48300180 0x48300180 0x80 /* EQEP */
+ 0x48300200 0x48300200 0x80>; /* EHRPWM */
+
+ /* child nodes go here */
+};
diff --git a/Documentation/devicetree/bindings/pwm/pwm.txt b/Documentation/devicetree/bindings/pwm/pwm.txt
index 73ec962bfe8..06e67247859 100644
--- a/Documentation/devicetree/bindings/pwm/pwm.txt
+++ b/Documentation/devicetree/bindings/pwm/pwm.txt
@@ -37,10 +37,21 @@ device:
pwm-names = "backlight";
};
+Note that in the example above, specifying the "pwm-names" is redundant
+because the name "backlight" would be used as fallback anyway.
+
pwm-specifier typically encodes the chip-relative PWM number and the PWM
-period in nanoseconds. Note that in the example above, specifying the
-"pwm-names" is redundant because the name "backlight" would be used as
-fallback anyway.
+period in nanoseconds.
+
+Optionally, the pwm-specifier can encode a number of flags in a third cell:
+- bit 0: PWM signal polarity (0: normal polarity, 1: inverse polarity)
+
+Example with optional PWM specifier for inverse polarity
+
+ bl: backlight {
+ pwms = <&pwm 0 5000000 1>;
+ pwm-names = "backlight";
+ };
2) PWM controller nodes
-----------------------
diff --git a/Documentation/devicetree/bindings/pwm/spear-pwm.txt b/Documentation/devicetree/bindings/pwm/spear-pwm.txt
new file mode 100644
index 00000000000..3ac779d8338
--- /dev/null
+++ b/Documentation/devicetree/bindings/pwm/spear-pwm.txt
@@ -0,0 +1,18 @@
+== ST SPEAr SoC PWM controller ==
+
+Required properties:
+- compatible: should be one of:
+ - "st,spear320-pwm"
+ - "st,spear1340-pwm"
+- reg: physical base address and length of the controller's registers
+- #pwm-cells: number of cells used to specify PWM which is fixed to 2 on
+ SPEAr. The first cell specifies the per-chip index of the PWM to use and
+ the second cell is the period in nanoseconds.
+
+Example:
+
+ pwm: pwm@a8000000 {
+ compatible ="st,spear320-pwm";
+ reg = <0xa8000000 0x1000>;
+ #pwm-cells = <2>;
+ };
diff --git a/Documentation/devicetree/bindings/pwm/ti,twl-pwm.txt b/Documentation/devicetree/bindings/pwm/ti,twl-pwm.txt
new file mode 100644
index 00000000000..2943ee5fce0
--- /dev/null
+++ b/Documentation/devicetree/bindings/pwm/ti,twl-pwm.txt
@@ -0,0 +1,17 @@
+Texas Instruments TWL series PWM drivers
+
+Supported PWMs:
+On TWL4030 series: PWM1 and PWM2
+On TWL6030 series: PWM0 and PWM1
+
+Required properties:
+- compatible: "ti,twl4030-pwm" or "ti,twl6030-pwm"
+- #pwm-cells: should be 2. The first cell specifies the per-chip index
+ of the PWM to use and the second cell is the period in nanoseconds.
+
+Example:
+
+twl_pwm: pwm {
+ compatible = "ti,twl6030-pwm";
+ #pwm-cells = <2>;
+};
diff --git a/Documentation/devicetree/bindings/pwm/ti,twl-pwmled.txt b/Documentation/devicetree/bindings/pwm/ti,twl-pwmled.txt
new file mode 100644
index 00000000000..cb64f3acc10
--- /dev/null
+++ b/Documentation/devicetree/bindings/pwm/ti,twl-pwmled.txt
@@ -0,0 +1,17 @@
+Texas Instruments TWL series PWM drivers connected to LED terminals
+
+Supported PWMs:
+On TWL4030 series: PWMA and PWMB (connected to LEDA and LEDB terminals)
+On TWL6030 series: LED PWM (mainly used as charging indicator LED)
+
+Required properties:
+- compatible: "ti,twl4030-pwmled" or "ti,twl6030-pwmled"
+- #pwm-cells: should be 2. The first cell specifies the per-chip index
+ of the PWM to use and the second cell is the period in nanoseconds.
+
+Example:
+
+twl_pwmled: pwmled {
+ compatible = "ti,twl6030-pwmled";
+ #pwm-cells = <2>;
+};
diff --git a/Documentation/devicetree/bindings/pwm/vt8500-pwm.txt b/Documentation/devicetree/bindings/pwm/vt8500-pwm.txt
new file mode 100644
index 00000000000..bcc63678a9a
--- /dev/null
+++ b/Documentation/devicetree/bindings/pwm/vt8500-pwm.txt
@@ -0,0 +1,17 @@
+VIA/Wondermedia VT8500/WM8xxx series SoC PWM controller
+
+Required properties:
+- compatible: should be "via,vt8500-pwm"
+- reg: physical base address and length of the controller's registers
+- #pwm-cells: should be 2. The first cell specifies the per-chip index
+ of the PWM to use and the second cell is the period in nanoseconds.
+- clocks: phandle to the PWM source clock
+
+Example:
+
+pwm1: pwm@d8220000 {
+ #pwm-cells = <2>;
+ compatible = "via,vt8500-pwm";
+ reg = <0xd8220000 0x1000>;
+ clocks = <&clkpwm>;
+};
diff --git a/Documentation/devicetree/bindings/spi/nvidia,tegra20-sflash.txt b/Documentation/devicetree/bindings/spi/nvidia,tegra20-sflash.txt
index 8cf24f6f0a9..7b53da5cb75 100644
--- a/Documentation/devicetree/bindings/spi/nvidia,tegra20-sflash.txt
+++ b/Documentation/devicetree/bindings/spi/nvidia,tegra20-sflash.txt
@@ -13,7 +13,7 @@ Recommended properties:
Example:
-spi@7000d600 {
+spi@7000c380 {
compatible = "nvidia,tegra20-sflash";
reg = <0x7000c380 0x80>;
interrupts = <0 39 0x04>;
diff --git a/Documentation/devicetree/bindings/spi/nvidia,tegra20-slink.txt b/Documentation/devicetree/bindings/spi/nvidia,tegra20-slink.txt
index f5b1ad1a1ec..eefe15e3d95 100644
--- a/Documentation/devicetree/bindings/spi/nvidia,tegra20-slink.txt
+++ b/Documentation/devicetree/bindings/spi/nvidia,tegra20-slink.txt
@@ -13,7 +13,7 @@ Recommended properties:
Example:
-slink@7000d600 {
+spi@7000d600 {
compatible = "nvidia,tegra20-slink";
reg = <0x7000d600 0x200>;
interrupts = <0 82 0x04>;
diff --git a/Documentation/devicetree/bindings/spi/spi_atmel.txt b/Documentation/devicetree/bindings/spi/spi_atmel.txt
new file mode 100644
index 00000000000..07e04cdc0c9
--- /dev/null
+++ b/Documentation/devicetree/bindings/spi/spi_atmel.txt
@@ -0,0 +1,26 @@
+Atmel SPI device
+
+Required properties:
+- compatible : should be "atmel,at91rm9200-spi".
+- reg: Address and length of the register set for the device
+- interrupts: Should contain spi interrupt
+- cs-gpios: chipselects
+
+Example:
+
+spi1: spi@fffcc000 {
+ compatible = "atmel,at91rm9200-spi";
+ reg = <0xfffcc000 0x4000>;
+ interrupts = <13 4 5>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ cs-gpios = <&pioB 3 0>;
+ status = "okay";
+
+ mmc-slot@0 {
+ compatible = "mmc-spi-slot";
+ reg = <0>;
+ gpios = <&pioC 4 0>; /* CD */
+ spi-max-frequency = <25000000>;
+ };
+};
diff --git a/Documentation/x86/boot.txt b/Documentation/x86/boot.txt
index f15cb74c4f7..406d82d5d2b 100644
--- a/Documentation/x86/boot.txt
+++ b/Documentation/x86/boot.txt
@@ -373,7 +373,7 @@ Protocol: 2.00+
1 Loadlin
2 bootsect-loader (0x20, all other values reserved)
3 Syslinux
- 4 Etherboot/gPXE
+ 4 Etherboot/gPXE/iPXE
5 ELILO
7 GRUB
8 U-Boot
@@ -381,6 +381,7 @@ Protocol: 2.00+
A Gujin
B Qemu
C Arcturus Networks uCbootloader
+ D kexec-tools
E Extended (see ext_loader_type)
F Special (0xFF = undefined)
10 Reserved
diff --git a/Documentation/xtensa/atomctl.txt b/Documentation/xtensa/atomctl.txt
new file mode 100644
index 00000000000..10a8d1ff35e
--- /dev/null
+++ b/Documentation/xtensa/atomctl.txt
@@ -0,0 +1,44 @@
+We Have Atomic Operation Control (ATOMCTL) Register.
+This register determines the effect of using a S32C1I instruction
+with various combinations of:
+
+ 1. With and without an Coherent Cache Controller which
+ can do Atomic Transactions to the memory internally.
+
+ 2. With and without An Intelligent Memory Controller which
+ can do Atomic Transactions itself.
+
+The Core comes up with a default value of for the three types of cache ops:
+
+ 0x28: (WB: Internal, WT: Internal, BY:Exception)
+
+On the FPGA Cards we typically simulate an Intelligent Memory controller
+which can implement RCW transactions. For FPGA cards with an External
+Memory controller we let it to the atomic operations internally while
+doing a Cached (WB) transaction and use the Memory RCW for un-cached
+operations.
+
+For systems without an coherent cache controller, non-MX, we always
+use the memory controllers RCW, thought non-MX controlers likely
+support the Internal Operation.
+
+CUSTOMER-WARNING:
+ Virtually all customers buy their memory controllers from vendors that
+ don't support atomic RCW memory transactions and will likely want to
+ configure this register to not use RCW.
+
+Developers might find using RCW in Bypass mode convenient when testing
+with the cache being bypassed; for example studying cache alias problems.
+
+See Section 4.3.12.4 of ISA; Bits:
+
+ WB WT BY
+ 5 4 | 3 2 | 1 0
+ 2 Bit
+ Field
+ Values WB - Write Back WT - Write Thru BY - Bypass
+--------- --------------- ----------------- ----------------
+ 0 Exception Exception Exception
+ 1 RCW Transaction RCW Transaction RCW Transaction
+ 2 Internal Operation Exception Reserved
+ 3 Reserved Reserved Reserved