54 SPARC JPS1 Implementation Supplement:
mem_address_not_aligned
quadword-load ASIs
data_access_exception
Description
The memory access for a load quad instruction with behaves as if the following TTE is set:
byte boundary.
ASIs 3416 and 3C16 are supported in SPARC64 V in addition to those for Load Quadword Atomic for virtually addressed data (ASIs 2416 and 2C16).
In addition to the usual traps for LDDA using a privileged ASI, a
exception occurs for a noncacheable access or for the use of the with any instruction other than LDDA. A
exception is generated if the access is not aligned on a 16-
ASIs 3416 and 3C16 are used with the LDDA instruction to atomically read a 128-bit data item, using physical addressing. The data are placed in an even/odd pair of 64- bit registers. The lowest-address 64 bits are placed in the even-numbered register; the highest-address 64 bits are placed in the odd-numbered register. The reference is made from the nucleus context.
ASI_QUAD_LDD_PHYS{_L}

A.30 Load Quadword, Atomic [Physical]

The Load Quadword ASIs in this section are specific to SPARC64 V, as an extension to SPARC JPS1.

 

 

 

 

 

opcode

imm_asi

 

ASI value

operation

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

LDDA

ASI_QUAD_LDD_PHYS

 

3416

128-bit atomic load, physically

 

 

 

 

 

 

 

 

 

 

 

 

addressed

 

 

 

 

 

 

 

 

LDDA

ASI_QUAD_LDD_PHYS_L

3C16

128-bit atomic load, little-endian,

 

 

 

 

 

 

 

 

 

 

 

 

physically addressed

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Format (3) LDDA

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

11

 

rd

 

010011

 

rs1

i=0

 

imm_asi

 

rs2

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

11

 

rd

 

010011

 

rs1

i=1

 

simm_13

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

31

30

29

25 24

19 18

14

13

 

5

4

0

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Assembly Language Syntax

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

ldda

[reg_addr] imm_asi, regrd

 

 

 

 

 

 

 

 

 

 

 

ldda

[reg_plus_imm] %asi, regrd

 

 

 

 

 

 

Fujitsu SPARC64 V • Release 1.0, 1 July 2002

Page 65
Image 65
Fujitsu Fujitsu SPARC64 V manual Load Quadword, Atomic Physical, Format 3 Ldda