Intel ITANIUM ARCHITECTURE - SOFTWARE DEVELOPERS VOLUME 3 REV 2.3, Manual

Page: 718 / 1898

2:470 Volume 2, Part 1: Processor Abstraction Layer
PAL_VM_TR_READ
PAL_VM_TR_READ – Read a Translation Register (261)
Purpose:
Reads a translation register.
Calling Conv:
Stacked Registers
Mode:
Physical
Buffer:
Not dependent
Arguments:
Returns:
Status:
Description:
This procedure reads the specified translation register and returns its data in the buffer
starting at
tr_buffer . The format of the data is returned in Translation Insertion Format,
as described in Figure 4-5, “Translation Insertion Format,” on page 2:54 . In addition,
bit 0 of the IFA in Figure 4-5 (an ignored field in the figure) will return whether the
translation is valid. If bit 0 is 1, the translation is valid.
Some fields of the translation register returned may be invalid. The validity of these
fields is indicated by the return argument
TR_valid . If these fields are not valid, the
caller should ignore the indicated fields when reading the translation register returned
in
tr_buffer .
• av – denotes that the access rights field is valid
• pv – denotes that the privilege level field is valid
• dv – denotes that the dirty bit is valid
• mv – denotes that the memory attributes are valid.
A value of 1 denotes a valid field. A value of 0 denotes an invalid field. Any value
returned in an invalid field must be ignored.
The tr_buffer parameter should be aligned on an 8 byte boundary.
Note: This procedure may have the side effect of flushing all the translation cache
entries depending on the implementation.
Argument Description
index Index of PAL_VM_TR_READ within the list of PAL procedures.
reg_num Unsigned 64-bit number denoting which TR to read.
tr_type Unsigned 64-bit number denoting whether to read an ITR (0) or DTR (1). All other values are
reserved.
tr_buffer 64-bit pointer to the 32-byte memory buffer in which translation data is returned.
Return Value Description
status Return status of the PAL_VM_TR_READ procedure.
TR_valid Formatted bit vector denoting which fields are valid. See Figure 11-50 .
Reserved 0
Reserved 0
Status Value Description
0 Call completed without error.
-2 Invalid argument
-3 Call completed with error.
Figure 11-50. Layout of TR_valid Return Value
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
Reserved mv dv pv av
63 62 61 60 59 58 57 56 55 54 53 52 51 50 49 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 32
Reserved