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Registers
1378
SPRUH82C – April 2013 – Revised September 2016
Copyright © 2013–2016, Texas Instruments Incorporated
Serial ATA (SATA) Controller
28.4.4 Ports Implemented Register (PI)
The ports implemented register (PI) indicates which ports are exposed by the SATASS and are available
for software to use. It is loaded by the BIOS. For example, if the SATASS supports 8 Ports as indicated in
the CAP.NP, only Ports 1, 3, 5, and 7 could be available, while Ports 0, 2, 4, and 6 being unavailable.
Note that this sub-system only has a single port so software should write a 0x1 to this bit at power-up. The
PI is shown in
and described in
Figure 28-4. Ports Implemented Register (PI)
31
16
Reserved
R-0
15
2
1
0
Reserved
PI[
n
]
R-0
W/RO-0
LEGEND: R/W = Read/Write; R = Read only; W/RO: written once after hard reset by firmware, then remain as read-only;
-
n
= value after reset
Table 28-8. Ports Implemented Register (PI) Field Descriptions
Bit
Field
Value
Description
31-2
Reserved
0
Reserved.
1-0
PI[
n
]
0-1
Ports Implemented. This register is bit significant. If a bit
n
is set to 1, the corresponding Port is
available for software to use. If a bit
n
is cleared to 0, the Port is not available for software to use. The
maximum number of bits that can be set to 1 is CAP.NP + 1. At least one bit must be set to 1. The
contents of this register are relevant to the command completion coalescing ports register
(CCC_PORTS).
28.4.5 AHCI Version Register (VS)
The AHCI version register (VS) indicates the version of the Synopsis AHCI core embedded in the
SATASS. The VS is shown in
and described in
Figure 28-5. AHCI Version Register (VS)
31
16
MJR
R-1
15
0
MNR
R-100h
LEGEND: R = Read only; -
n
= value after reset
Table 28-9. AHCI Version Register (VS) Field Descriptions
Bit
Field
Value
Description
31-16
MJR
1
Major Revision Number.
15-0
MNR
100h
Minor Revision Number.