MPC8280 datasheet(133/1386 Pages) FREESCALE

133 / 1386 page

G2_LE Core

MPC8280 PowerQUICC II Family Reference Manual, Rev. 1

Freescale Semiconductor

2-17

•

Memory control instructions—These provide control of caches, TLBs, and segment registers.

— Supervisor-level cache management

— User-level cache management

— Segment register manipulation

— TLB management

•

The G2_LE core implements the following instructions, which are defined as optional by the

PowerPC architecture:

— External Control In Word Indexed (eciwx)

— External Control Out Word Indexed (ecowx)

— Floating Select (fsel)

— Floating Reciprocal Estimate Single-Precision (fres)

— Floating Reciprocal Square Root Estimate (frsqrte)

— Store Floating-Point as Integer Word (stfiwx)

Note that this grouping of the instructions does not indicate which execution unit executes a particular

instruction or group of instructions.

Integer instructions operate on byte, half-word, and word operands. The PowerPC architecture uses

instructions that are four bytes long and word-aligned. It provides for byte, half-word, and word operand

loads and stores between memory and a set of 32 GPRs. Floating-point instructions operate on

single-precision (one word) and double-precision (one double word) floating-point operands. It also

provides for word and double-word operand loads and stores between memory and a set of 32

floating-point registers (FPRs).

Computational instructions do not modify memory. To use a memory operand in a computation and then

modify the same or another memory location, the memory contents must be loaded into a register,

modified, and written back to the target location with separate instructions. Decoupling arithmetic

instructions from memory accesses increases throughput by facilitating pipelining.

Processors that implement the PowerPC architecture follow the program flow when they are in the normal

execution state. However, the flow of instructions can be interrupted directly by the execution of an

instruction or by an asynchronous event. Either kind of exception may cause one of several components

of the system software to be invoked.

2.3.2.3

MPC8280 Implementation-Specific Instruction Set

The G2_LE core instruction set is defined as follows:

•

The core provides hardware support for all 32-bit PowerPC instructions.

•

The core provides the following two implementation-specific instructions used for software

tablesearch operations following TLB misses:

— Load Data TLB Entry (tlbld)

— Load Instruction TLB Entry (tlbli)

MPC8280 датащи(PDF) 133 Page - Freescale Semiconductor, Inc

MPC8280 датащи(HTML) 133 Page - Freescale Semiconductor, Inc

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

датащи скачать

ссылки URL