CS5535 datasheet(62/555 Pages) NSC

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Revision 0.8

Global Concepts and Features (Continued)

3.7.7

Legacy I/O Decoding

Table 3-6 details the legacy I/O range for 000h through

4FFh. Each I/O location has a read/write (R/W) capability.

Note the following abbreviations:

---

Unknown or can not be determined.

Yes

Read and Write the register at the indicated

location. No shadow required.

Write only. Value written can not be read back.

Reads do not contain any useful information.

Read only. Writes have no effect.

Shw

The value written to the register can not be read

back via the same I/O location.

Read back is accomplished via a “Shadow”

Shw@

Reads of the location return a constant or

meaningless value.

Shw$

Reads of the location return a status or some

other meaningful information.

Rec

Writes to the location are “recorded” and written

to the LPC.

Reads to the location return the recorded value.

The LPC is not read.

Table 3-5. Diverse Device Space Map Except Legacy I/O

Device

MSR Space (Note 1)

I/O Space

Memory Space

Standard GeodeLink Device

MSRs plus:

SMB LBAR, ACPI LBAR,

PM LBAR, GPIO LBAR,

MFGPT LBAR, NAND LBAR,

KEL LBAR, KEL LBAR,

IRQ Mapper LBAR,

Legacy Controls,

DMA Mappers,

Shadow Registers,

LPC Controls, and

Memory Mask.

NOR Flash address control.

Located by associated LBAR.

Defaults disabled.

008 Bytes SMB,

016 Bytes ACPI,

064 Bytes PM Support,

256 Bytes GPIO and ICFs,

064 Bytes MFGPTs,

016 Bytes NAND Flash, and

032 Bytes IRQ Mapper.

All I/O that does not hit one of the

items above and does not hit a

legacy address, is directed to the

LPC bus.

16-Byte KEL Host Controller reg-

ister set at LBAR. Defaults dis-

abled.

NOR Flash per LBAR.

All other memory accesses are

directed to the LPC bus.

Note 1. See Section 3.8 "Standard GeodeLink Device MSRs" on page 67 for register descriptions.

Table 3-6. Legacy I/O: 000h-4FFh

I/O Addr.

Function

Size

R/W

Comment

000h

Slave DMA Address - Channel 0

8-bit

Yes