Winbond Electronics W90210F Datasheet

W90210F

PA-RISC Embedded Controller

1 Version 1.4, 10/8/97

The above information is the exclusive intellectual property of Winbond Electronics Corp. and shall not be disclosed, distributed or reproduced without permission from Winbond.

W90210F

Table of Contents

TABLE OF CONTENTS 2

1. GENERAL DESCRIPTION 5

2. FEATURES 6

3. W90210F 208-PIN PQFP PIN CONFIGURATION 7

4. W90210F PIN DESCRIPTION 8

5. W90210F CPU CORE 12

5.1 Architecture 12

5.1.1 PA-RISC Rev. 1.1 third edition 12

5.1.2 Level 0 implementation 12

5.1.3 Multimedia Extension Instruction Set 12

5.2 CPU resources 12

5.2.1 General registers 12

5.2.2 Shadow registers 13

5.2.3 Processor Status Word (PSW) 13

5.2.4 Control registers 14

5.2.5 W90210F External Interrupt Request register (EIRR; CR23) 15

5.2.6 AIRs (Architecture Invisible Registers) 15

5.3 Implementation of the PA-RISC instructions 15

5.3.1 Implementation of Level 0 instructions 16

5.3.2 Implementation of cache-related instructions 16

5.3.3 PA-RISC multimedia extension instruction set 17

5.3.4 DIAG instruction 17

5.4. Debug Special Function Unit 19

5.5 Addressing and access control 20

5.5.1 Memory and I/O space 20

5.5.2 RESET addresses 20

5.5.3 Access control 20

5.6 Interruptions 21

6. PIPELINE ARCHITECTURE 22

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W90210F

6.1 Branch prediction 22

6.2 Load use interlock 23

7. ON-CHIP CACHE MEMORIES 24

7.1 Instruction cache 24

7.2 Data cache 24

7.2.1 Write-through Cache Support 25

7.3 Non-cacheable address space 25

8. MEGACELLS DESCRIPTION 26

8.1 DRAM Controller & ROM Controller 26

8.1.1 DRAM controller 26

8.1.2 ROM controller 27

8.1.3 Memory controller registers 27

8.2 DMA Controller (DMAC) 30

8.2.1 Register Description: 30

8.3 Timer / Counter 32

8.4 Serial I/O 33

8.4.1 UART Register Definition 33

8.5 Parallel Port 36

8.5.1 ECP Register Description 36

9. TIMING DIAGRAM 39

9.1 Memory controller 39

9.1.1 DRAM AC Timimg 39

9.1.2 ROM AC Timimg 39

9.2 DMA Controller 41

9.2.1 DMA device register read timing 41

9.2.2 DMA device register write timing 42

9.2.3 DMA demand mode data read cycles 43

9.2.4 DMA demand mode data write cycles 44

9.2.5 DMA block mode data read cycles 45

9.2.6 DMA block mode data write cycles 46

APPENDIX A. PA-RISC MULTIMEDIA INSTRUCTION SET 48

APPENDIX B. DIAGNOSTIC INSTRUCTIONS 53

3 Version 1.4, 10/8/97

The above information is the exclusive intellectual property of Winbond Electronics Corp. and shall not be disclosed, distributed or reproduced without permission from Winbond.

W90210F

4 Version 1.4, 10/8/97

The above information is the exclusive intellectual property of Winbond Electronics Corp. and shall not be disclosed, distributed or reproduced without permission from Winbond.

W90210F

1. General Description

The W90210F Embedded Controller is part of Winbond′s W90K Embedded processor family. The processor

is a high-performance, highly integrated 32-bit processor intended for a wide range of embedded applications, such as set-top box, web browser, X-terminal, and visual/data communication devices..

The W90210F CPU core is based on the HP PA-RISC architecture and is upward code compatible with the W90K. The PA-RISC architecture incorporates traditional RISC elements, such as instruction pipelining, a register-toregister instruction set and a large, general-purpose register file. Separate on-chip instruction and data caches allow the W90210F to fetch an instruction and access data in a single processor cycle.

The W90210F includes several features that greatly increase performance, reduce system component count and ease the overall system design task. In addition to its cache memories, the W90210F′s on-chip support features include a DRAM controller, ROM/FLASH ROM interface, PCI bridge, DMA controller, two serial ports with FIFO, IEEE 1284 parallel port, timer/counters, and enhanced debug support- all features that are commonly required in embedded applications.

Figure 1.1 shows the system diagram of W90210F.

W90K CPU core

internal bus

PCI Bridge

DRAM

Interface

ROM/

FLASH ROM

Interface

Bus Interface Unit

DRAM array

Memory Data Bus

8/16/32-bit

ROM

latch

Figure 1.1 W90210F System Diagram

CPU RST, CPU CLOCK

Address/Control Bus

2-Channel

DMA

Controller

8-bit DMA

I/O Bus

32-bit Data Bus

Peripheral

Bridge

Serial

Ports

ECP

Timer

5 Version 1.4, 10/8/97

The above information is the exclusive intellectual property of Winbond Electronics Corp. and shall not be disclosed, distributed or reproduced without permission from Winbond.

W90210F

2. Features

Main features of the W90210F

• PA-RISC architecture

PA-RISC 1.1 third edition instruction set

PA-RISC level zero implementation

Support PA-RISC Multimedia Extension 1.0 instruction set

W90K binary compatible for user software

• High-performance implementation

Five-stage pipeline

Precise, efficient handling of pipeline stalls and exceptions

Delayed branch with static branch prediction

Forward: not taken

Backward: taken

One-cycle stall when prediction is wrong

HIT under miss

Both load and store can be queued when miss

Load/store single cycle execution after previous miss

• On-chip cache memory

Internal I-cache: Direct mapped, 4 KB cache (256 entries, four words/entry)

Wrap around fetching when cache miss Cache freeze capability

Internal D-cache: 2-way set associative, 2 KB cache (2×64 entries, four words/entry)

Write-back cache with write buffer Write-through option New line send to CPU before dirty line write back

• Enhanced debug capability

Debug SFU supports both instruction breakpoints and data breakpoints

• High on-chip integration and simple I/O interface

486-like bus interface for CPU core

Memory controller to support four banks of DRAM and ROM/FLASH ROM

2-channel 8-bit DMA controller

PCI bridge

Two Serial ports with FIFO

Extended Capabilities Port (ECP)

Two 24-bit timer/counters

• Power Down mode

Provide power down mode for power saving operation

6 Version 1.4, 10/8/97

The above information is the exclusive intellectual property of Winbond Electronics Corp. and shall not be disclosed, distributed or reproduced without permission from Winbond.

W90210F

3. W90210F 208-Pin PQFP Pin Configuration

M A 2

M D 2 3

2 2

S I

MA3 VDD MA4 MA5 VSS MA6 MA7 VSSI MA8 MA9 VDDI MA10 MA11 ROMEN ROMRW# ROMOE# RCS#0 RCS#1 VDD RCS#2 RCS#3 PCLK VSS RST OSC VSSI RCIRST PCICLK VDDI GNT0# GNT1# PREQ0# PREQ1# PDA31 PDA30 PDA29 PDA28 PDA27 VSS PDA26 PDA25 VDD PDA24 COMBE3 PDA23 PDA22 PDA21 PDA20 PDA19 PDA18 PDA17 PDA16

0 5

2 0 0

1 9 5

1 9 0

1 8 5

W90210F

1 8 0

1 7 5

1 7 0

1 6 5

208-pin PQFP

5 5

6 0

6 5

E 1

7 0

V S S I

7 5

P D A 1 1

E 0

8 0

8 5

P D A 4

9 0

9 5

1 6 0

1 0 0

R T S 1 n

nStrobe

155

nAutoFd nInit nSelectIn ED0 ED1

150

ED2 ED3 ED4 VDD ED5

145

ED6 VSS ED7 Select PError

140

nACK nFAULT Busy CS1 CS0

135

DACK1 DACK0 DREQ1 VDDI DREQ0

130

DD0 VSSI DD1 DD2 DD3

125

DD4 DD5 DD6 DD7 TC1

120

TC0 IOR VDD IOW DMARDY

115

VSS DA0 DA1 DA2 DA3

110

DA4 DA5 DA6 DA7 DA8

105

DA9

7 Version 1.4, 10/8/97

The above information is the exclusive intellectual property of Winbond Electronics Corp. and shall not be disclosed, distributed or reproduced without permission from Winbond.

W90210F

4. W90210F Pin Description

RSTI24

CPU RESET input, high active

PCLK

I22CPU CLOCK input

OSCI25

14.318Mhz Oscillator input for Timer, UART

INTA#

INTB#

INTC#

INTD#

I87888991

PCI Interrupt input, level senstive, low active signal. Once the

INTx# signal is asserted, it remains asserted until the device driver

clear the pending request. When the request is cleared, the device

deasserts its INTx# signal.

PREQ0#

PREQ1#

I3233

PCI Request input, indicates to the PCI arbiter that this agent

desires use of the bus.

GNT0#

GNT1#

O3031

PCI Grant output, indicates to the agent that access to the bus

has been granted.

PLOCK#

I61PCI Lock signal, indicates an atomic operation that may require

multiple transactions to complete. When PLOCK# is asserted,

non-exclusive transactions may proceed to an address that is not

currently locked.

PCIRST#

O27PCI Reset output, is used to bring PCI-specific registers,

sequencers, and signals to a consistent state. Low active.

PCICLK

O28PCI Clock output, provides timing for all transactions on PCI and is

an input to every PCI device.

SERR#

I63PCI System Error is for reporting address parity errors, data parity

errors on the Special Cycle command, or any other system error

where the result will be catastrophic. The assertion of SERR# is

synchronous to the clock and meets the setup and hold times of

all bused signals.

PERR#

I/O62PCI Parity Error is only for the reporting of data parity errors during

all PCI transactions except a Special Cycle. The PERR# pin is

sustained tri-state and must be driven active by the agent receiving

data two clocks following the data when a data parity error is

detected. The minimum duration of PERR# is one clock for each

data phase that a data parity error is detected. An agent cannot

report a PERR# until it has claimed the access by asserting

DEVSEL# (for a target) and completed a data phase or is the

master of the current transaction.

PIN Name DIR PIN # DESCRIPTION CPU Signal

PCI LOCAL BUS

for more detail description of the PCI signals please refer to the PCI LOCAL BUS

SPECIFICATION

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8 Version 1.4, 10/8/97

W90210F

PDA[31:0]

tri-state

I/O

34-38, 40-41, 43,

45-52, 68-75, 78-

79, 81-86

PCI tri-state Address/Data bus, Address and Data are multiplexed

on the same PCI pins. A bus transaction consists of an address

phase followed by one or more data phases. PCI supports both

read and write bursts. The address phase is the clock cycle in

which FRAME# is asserted. During the address phase PDA[31:0]

contain a physical address. During data phases PDA[7:0] contain

the least significant byte (lsb) and PDA[31:24] contain the most

significant byte (msb). Write data is stable and valid when IRDY# is

asserted and read data is stable and valid when TRDY# is

asserted. Data is transferred during those clocks where both

IRDY# and TRDY# are asserted.

STOP#

I/O60PCI Stop indicates the current target is requesting the master to

stop the current transaction.

TRDY#

I/O58PCI Target Ready indicates the selected device’s ability to

complete the current data phase of the transaction. A data phase

is completed on any clock both TRDY# and IRDY# are sampled

asserted. During a read, TRDY# indicates that valid data is present

on PDA[31:0]. During a write, it indicates the target is prepared to

accept data. Wait cycles are inserted until both IRDY# and TRDY#

are asserted together.

DEVSEL#

I/O59PCI Device Select, when actively driven, indicates the driving

device has decoded its address as the target of the current

access. As an input, DEVSEL# indicates whether any device on

the bus has been selected.

C/BE[3:0]#

I/O

44,53,66,76

PCI Bus Command and Byte Enables are multiplexed on the

same PCI pins. During the address phase of a transaction,

C/BE[3:0]# define the bus command. During the data phase

C/BE[3:0]# are used as Byte Enables. The Byte Enables are valid

for the entire data phase and determine which byte lanes carry

meaningful data. C/BE[0]# applies to byte 0 (lsb) and C/BE[3]#

applies to byte 3 (msb).

FRAME#

I/O55PCI Cycle Frame is driven by the current master to indicate the

beginning and duration of an access. FRAME# is asserted to

indicate a bus transaction is beginning. While FRAME# is

asserted, data transfers continue. When FRAM# is deasserted,

the transaction is in the final data phase or has completed.

IRDY#

I/O56PCI Initiator Ready indicates the bus master’s ability to complete

the current data phase of the transaction. A data phase is

completed on any clock both IRDY# and TRDY# are sampled

asserted. During a write, IRDY# indicates that valid data is present

on PDA[31:0]. During a read, it indicates the master is prepared to

accept data. Wait cycles are inserted until both IRDY# and TRDY#

are asserted together.

PPAR

I/O65PCI Parity is even parity across PDA[31:0] and C/BE[3:0]#. PPAR

is stable and valid one clock after the address phase. For data

phases, PPAR is stable and valid one clock after either IRDY# is

asserted on a write transaction or TRDY# is asserted on a read

transaction. (PPAR has the same timing as PDA[31:0], but it is

delayed by one clock.) The mater drives PPAR for address and

write data phases; the target drives PPAR for read data phase.

DMA Interface

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W90210F

DREQ0

DREQ1

131

133

DMA Request signals request an external transfer on DMA

channel 0 (DREQ0) or DMA channel 1 (DREQ1).

DACK0

DACK1

134

135

DMA Acknowledge signals acknowledge an external transfer on

DMA channel 0 (DREQ0) or DMA channel 1 (DREQ1).

DMARDY

116

DMA Device Ready signal is used to extend the length of DMA

bus cycles. If a device wants to extend the DMA bus cycles, it will

force the DMARDY signal low when it decodes its address and

receives a IOR or IOW command.

CS0

CS1O136

137

DMA Chip Select signals select the corresponding I/O devices for

programming or DMA transfers.

DA[0:11]

114-104,102

12-bit DMA I/O Address Bus, bit 0 is the most significant bit.

IORO119

DMA I/O read signal is used to indicate to the I/O device that the

present bus cycle is an I/O read cycle.

IOWO117

DMA I/O write signal is used to indicate to the I/O device that the

present bus cycle is an I/O write cycle.

TC0

TC1O120

121

Terminal count for DMA channels, the pin is driven active for one

clock when byte count reaches zero and after the last transfer for

a DAM has completed.

DD[0:7]

I/O

130,128-122

8-bit DMA I/O Data bus, bit 0 is the most significant bit.

ECP Interface

For more detail description of the ECP interface signals, please

refer to the

Busy

138

ECP busy input signal

nFault

139

ECP fault input

nAck

140

ECP acknowledge input

PError

141

ECP parity error

Select

142

ECP Select

nSelectIn

153

ECP select output

nInitO154

ECP initialization

nAutoFd

155

ECP Autofeed

nStrobe

156

ECP Strobe

ED[0:7]

I/O

152-148,146-

145,143

Bi-directional ECP Data bus, ED[0] is the most significant bit

(msb).

RAS#[0:3]

201-204

DRAM Row Address Strobe, Banks 0-3. These signals are used

to select the DRAM row address. A High-to-Low transition on one

of these signals causes a DRAM in the corresponding bank to

latch the row address and begin an access.

CAS#[0:3]

195,197-198,200

DRAM Column Address Strobes, Byte 0-3. These signals are

used to select the DRAM column address. A High-to-Low

transition on these signals causes the DRAM selected by

RAS#[0:3] to latch the column address and complete the access.

WE#

205

DRAM Write Enable signal is used to write the selected DRAM

bank.

RCS#[0:3]

17-18,20-21

ROM Chip Selects, Banks 0-3. A low level on one of these signals

selects the memory devices in the corresponding ROM bank.

ROMEN

O14ROM Address Latch, ROM address are divided into two portions,

higher address bits and lower address bits, the address will be put

out on the MA bus in two consecutive cycles. The ROMEN signal

is used to latch the higher address bits in the first ROM address

cycle.

Memory Controller Interface

IEEE P1284 Standard

The above information is the exclusive intellectual property of Winbond Electronics Corp. and shall not be disclosed, distributed or reproduced without permission from Winbond.

10 Version 1.4, 10/8/97

W90210F

ROMRW#

O15FLASH ROM write enable. This signal is used to write data into

the mrmory in a ROM bank (such as Flash ROM).

ROMOE#

O16ROM output enable. This signal enables the selected ROM Bank

to drive the MD bus.

MA[0:11]

206-208,1,3-4,6-

7,9-10,12-13

Memory controller Memory Address bus. For DRAM access,

MA[0:11] is the DRAM row address and the DRAM column

address. For ROM/FLASH ROM access, MA[0:11] is the higher

portion ROM space address bits in the first ROM address cycle,

and the lower portion ROM space address bits after the first ROM

address cycle. MA[0] is the most significant bit (msb).

MD[0:31]

I/O

157-159,161-

162,164-167,169-

170,172-178,180-

181,183-194

Memory controller Data bus for both DRAM data and ROM space

data. Bit 0 is the most significant bit (msb).

COM1 Serial Port Signal

SIN1

I92COM1 serial data input from the communication link (modem or

peripheral device).

SOUT1

O94COM1 serial data output to the communication link (modem or

peripheral device).

CTS1n

I95COM1 clear to send signal

DSR1n

O96COM1 data set ready

DTR1n

I97COM1 data terminal ready

RTS1n

O98COM1 request to send

DCD1n

100

COM1 data carrier detect

RIN1n

103

COM1 ring indicator

SIN2

I99COM2 serial data input from the communication link (modem or

peripheral device).

SOUT2

101

COM2 serial data output to the communication link (modem or

peripheral device).

COM2 Serial Port Signal

The above information is the exclusive intellectual property of Winbond Electronics Corp. and shall not be disclosed, distributed or reproduced without permission from Winbond.

11 Version 1.4, 10/8/97

W90210F

5. W90210F CPU Core

The key characteristics of the W90210F CPU core have been designed specifically to meet the requirements of embedded control applications. The following subsections describe the essential features of the W90210F CPU core, including its architecture, implementations, and registers.

5.1 Architecture

The W90210F CPU core is designed based on the powerful PA-RISC architecture. Since our target is highend embedded applications, a great deal of design effort has been devoted to taking full advantage of this powerful architecture.

5.1.1 PA-RISC Rev. 1.1 third edition

The core of the W90210F is a processor unit that complies with PA-RISC architecture Rev. 1.1 third edition specifications. There are three kinds of operations to be executed by the processor; branch, load/store, and data transform. Most RISC architecture chooses to execute one of the three operations in an instruction. On the contrary, most PARISC instructions perform two operations listed above. For example, "ADD and BRANCH on the result of the ADD" can be done with one PA-RISC instruction. W90210F CPU core implements these powerful instructions and executes them in a single cycle. With such a powerful combined operation instruction set, the code size of W90210F can be much smaller than other RISC system. With the single cycle execution capability of these instructions, W90210F deliver very high throughput.

5.1.2 Level 0 implementation

In the PA-RISC architecture, a processor without an MMU is defined as the Level 0 implementation. All memory and I/O accesses in a level 0 PA-RISC processor are in real mode. W90210F is a level 0 implementation of PA-RISC architecture.

5.1.3 Multimedia Extension Instruction Set

The PA-RISC Multimedia extensions consists of a set of instructions which speed up the execution of common operations found in multimedia applications. In a 32-bit integer datapath, each multimedia instruction allows generic arithmetic operations to be executed in parallel on two pairs of 16-bit data. The PA-RISC multimedia extensions 1.0 instruction set is implemented by the W90210F CPU core.

5.2 CPU resources

The W90210F CPU core implements all the registers needed for a Level 0 processor as defined in the PARISC specifications. Some registers or register bits are not needed in a Level 0 processor and are defined as nonexistent registers or register bits. The W90210F CPU implements three AIRs (Architecture Invisible Registers) that can be accessed by executing DIAG instructions.

5.2.1 General registers

Thirty-two 32-bit general registers provide the central resource for all computation. They are numbered GR 0 through GR 31, and are available to all program at all privilege levels. GR 0, when referenced as source operand, delivers zeros. When GR 0 is used as destination, the result is discarded. GR 1 is the target of the ADD IMMEDIATE LEFT instruction. GR 31 is the instruction address offset link register for the base relative interspace procedure call instruction. GR 1 and GR 31 can also be used as general register.

12 Version 1.4, 10/8/97

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W90210F

GR 0

Permanent zero

GR 1

Target for ADDIL or General use

GR 2

General use

•

GR 30

General use

GR 31

Link register for BLE or General use

Reserved bits.

Data debug trap disable.

Instruction debug trap disable.

Little endian mode enable. When 1, all instruction fetches and loads/stores are little endian. The E bit after

RESET is set according to the state of ENDIAN pin.

Secure Interval Timer. When 1, the Interval Timer is readable only by code executing at the most privileged

level. When 0, the Interval Timer is readable by code executing at any privilege level.

Taken branch enable. When 1, any taken branch is terminated with a taken branch trap.

Higher-privilege transfer trap enable.

Lower-privilege transfer trap enable.

Nullify. The current instruction is nullified when this bit is 1.

Non-existent register bit.

Taken branch. The B-bit is set to 1 by any taken branch instruction and set to 0 otherwise.

Non-existent register bit.

Divide step correction. The integer primitive instruction records intermediate status in this bit to provide a

non-restoring divide primitive.

High-priority machine check mask. When 1, High Priority Machine Checks (HPMCs) are masked. Normally

0, this bit is set to 1 after HPMC and set to 0 after all other interruptions.

C/B

Carry/borrow bits. These bits are updated by some instructions from the corresponding carry/borrow

outputs of the 4-bit digit of the ALU.

Debug trap enable.

Non-existent register bit.

•

Figure 5.1 General Registers

5.2.2 Shadow registers

W90210F CPU core provides seven registers called shadow registers as defined in the PA-RISC architecture. The contents of GR1,8,9,16,17,24 and 25 are copied upon interruptions. Shadow registers reduce the state save and restore time by eliminating the need for general register saves and restores in interruption handlers. The behavior of the shadow registers is described below.

Before entering interrupt routine: Contents of seven general registers are copied into shadow registers in one cycle.

When executing RFIR: Contents of shadow registers are copied into general registers automatically in one cycle.

5.2.3 Processor Status Word (PSW)

The processor state of W90K is encoded in a 32-bit register called the Processor Status Word (PSW). The format of PSW is shown in figure 5.2. The old value of the PSW is saved in the Interrupt Processor Status Word (IPSW) when interruption occurs. The PSW is set to the contents of the IPSW by the RFIR (RETURN FROM INTERRUPTION and RESTORE) instruction.

1 1 1 1 1 1 1 2 2 2 2 2 2 2 3 3

0 1 2 ... 4 5 6 7 8 9 0 1 2 3 4 5 6 ... 3 4 5 6 7 8 9 0 1 Y Z rv E S T H L N X B C V M C/B rv G F R Q P D I

Field Description

13 Version 1.4, 10/8/97

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W90210F

Recovery counter enable. When 1, recovery counter traps occur if bit 0 of the recovery counter is a 1. This

bit also enables decrementing of the recovery counter.

Interrupt state collection enable. When 1, interruption state is collected.

Non-existent register bit.

External interruption, power failure interrupt, and low-priority machine check interruption unmask. When 1,

these interruptions are unmasked and can cause an interruption.

Figure 5.2 Processor Status Word

031CR 0

Recovery Counter

CR 1

reserved

CR 7

reserved

CR 8

Nonexistent registers

CR 9

Nonexistent registers

CR 10

reserved

SCR (8 bits)

CCR (8 bits)

CR 11

nonexistent

SAR (5)

CR 12

Nonexistent registers

CR 13

Nonexistent registers

CR 14

Interruption Vector Address

reserved

CR 15

External Interrupt Enable Masks

CR 16

Interval Timer

CR 17

Nonexistent registers

CR 18

Interruption Instruction Address Offset Queue

CR 19

Interruption Instruction Register

CR 20

Nonexistent registers

CR 21

Interruption Offset Register

CR 22

Interruption Processor Status Word

CR 23

External Interrupt Request Register

CR 24

Temporary Registers

CR 31

Temporary Registers

5.2.4 Control registers

There are twenty-five control registers in W90210F, numbered CR0, and CR8 through CR31, which contain system state information. Figure 5.3 shows the control registers. The access of CR 11, 16, 26, and 27 are described in the following table (table 5.4). Those control registers not listed in table 5.4 are only accessible by code executing at the most privileged level. Control registers 1 through 7 are reserved registers. The unused bits of the Coprocessor Configuration Register are reserved bits. The unused bits of the Shift Amount Register are nonexistent bits. In Level systems, CRs 8, 9, 12, 13, 17, and 20 are nonexistent registers.

•

Figure 5.3 Control registers

Privilege level for the access

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W90210F

CR 11

read/write at any privilege level

CR 16

PSW 'S'=0: read/write by any privilege level

PSW 'S'=1: read/write by privileged software

CR 26, 27

readable at any privilege level

writable at the most privileged level

Others

Accessible only at most privileged level

Table 5.4 Access of control registers

AIR[0]

Internal configuration register

AIR[1]

PSW register

AIR[2]

TMR register

AIR[3]

Memory configuration register 1

AIR[4]

Memory configuration register 2

AIR[5]

Memory configuration register 3

AIR[6]

Memory configuration register 4

AIR[7]

PCO register (program counter)

5.2.5 W90210F External Interrupt Request register (EIRR; CR23)

Bit

Number

EI[0:4] External

Interrupt

Description

0 00000 Timer_Int Interval Timer (CR16) interrupt request 1 10000 2 01000 3 11000 Serial Serial port interrupt request from COM2 4 00100 INTA PCI bus INTA# interrupt request 5 10100 INTB PCI bus INTB# interrupt request 6 01100 INTC PCI bus INTC# interrupt request 7 11100 INTD PCI bus INTD# interrupt request 8 00010 Parallel_Int Parallel port interrupt request

9 10010 Serial_Int Serial port interrupt request from COM1 10 01010 DMA_Int DMA interrupt request 11 11010 TC_Int Timer/Counter interrupt request

12 - 31 - - Reserved

Table 5.5 External Interrupt Request Register

5.2.6 AIRs (Architecture Invisible Registers)

There are eight AIRs in the W90210F. AIR[0] controls the internal cache configuration, burst mode, and default endian. AIR[0] is documented in this data sheet. AIR[1] and AIR[2] are reserved for chip testing by Winbond, and their functions will not be disclosed to users. Attempting to access these two registers may cause programs to be executed with unpredictable results. Memory configuration registers are used for programming the configuration of W90210F memory space. AIR[7] is the PCO register, this AIR can only be accessed through the JTAG ICE interface.

Important: Enabling or disabling the internal I-cache with MTAIR[0] will invalidate all I-cache entries automatically.

Enabling the internal D-cache with MTAIR[0] will invalidate all cache entries without dirty data entries being written back. Disabling the D-cache, however, will not invalidate cache entries.

Disabling the internal D-cache with MTAIR[0] will cause dirty data to be left in the D-Cache and not automatically written into memory. When a program references the dirty data location, stale data in memory will be returned. To prevent this, a cache invalidation routine should be performed before the internal D-cache is disabled. The invalidation routine must flush all cache entries one by one. This will invalidate the cache and also write back any dirty data.

AIR[1] and AIR[2] are reserved registers and should never be written to or read from them. Accessing these registers will cause unpredictable result.

5.3 Implementation of the PA-RISC instructions

The above information is the exclusive intellectual property of Winbond Electronics Corp. and shall not be disclosed, distributed or reproduced without permission from Winbond.

Table 5.6 W90210F CPU core AIRs

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W90210F

The W90210F CPU core implements all the instructions specified in the PA-RISC Rev. 1.1 third edition.

PDTLB

Purge data TLB

PITLB

Purge instruction TLB

PDTLBE

Purge data TLB entry

PITLBE

Purge instruction TLB entry

IDTLBA

Insert data TLB address

IITLBA

Insert instruction TLB address

IDTLBP

Insert data TLB protection

IITLBP

Insert instruction TLB protection

LPA

Load physical address

Undefined instruction

LCI

Load coherence index

Undefined instruction

LDWAX

Load word absolute index

Same as LDWX if priv=0

LDWAS

Load word absolute short

Same as LDWS if priv=0

STWAS

Store word absolute short

Same was STWS if priv=0

GATE

Gateway

Always promote priv to 0

Branch vectored

Demote priv to any non zero value

BLE

Branch external

Branch and link external

Demote priv to any non zero value, IASQ is nonexistent

RFI

RFIR

Return from interrupt

Return from interrupt and restore

IASQ is nonexistent

LDSID

Load space identifier

0 is written into specified GR

MTSP

Move to space register

Executed as null instruction

MTCTL

Move to control register

Executed as null instruction if target is 8,9,12,13,17 or

MFSP

Move from space register

is written into specified GR

MFCTL

Move from control register

0 is written into specified GR if source is 8,9,12,13,17 or

PROBER

Probe read access

Always set target GR to 1

PROBERI

Probe read access immediate

Always set target GR to 1

PROBEW

Probe write access

Always set target GR to 1

PROBEWI

Probe write access immediate

Always set target GR to 1

W90210F executes these instructions with results that comply to the PA-RISC architecture. MMU related instructions are executed by W90210F as defined in the PA-RISC architecture for a Level 0 processor. PA-RISC multimedia extension 1.0 instruction set is also supported by W90210F. To speed up multimedia operations in some applications, three additional instructions are defined through the diagnostic instructions. In addition to that, debug SFU is provided to enhance the debug capability. The chip also implements DIAG instructions defined by Winbond for chip testing, diagnostics, and programming the internal AIR (architecture invisible register). These DIAG instructions comply with the PA-RISC DIAG instructions.

5.3.1 Implementation of Level 0 instructions

In the Level 0 processor implementation, the S-fields of all instructions are ignored and have no effect on the device functions. The following instructions for TLB handling are executed as null instructions, as specified in the architecture reference manual:

Instruction Function

Table 5.7 Instructions executed as null instructions

Table 5.8 lists the differences in instruction execution results in a Level 0 processor.

Instruction Description Difference

5.3.2 Implementation of cache-related instructions

The above information is the exclusive intellectual property of Winbond Electronics Corp. and shall not be disclosed, distributed or reproduced without permission from Winbond.

Table 5.8 Summary of Level 0 instruction differences

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W90210F

It is assumed that in the W90210F application system all DMA transfers will be completed in order. The

SYNCDMA

Null

FDCE, FICE

See description above

FDC, FDCE, FIC, FICE, PDC

Affect internal cache only and are not broadcast to external bus.

HADD

Halfword parallel add

HSUB

Halfword parallel subtract

HAVE

Halfword parallel average

HSHRADD

Parallel halfword shift right and add

HSHLADD

Parallel halfword shift left and add

HALT

MTAIR

MFAIR

MTITAG

MFITAG

MTICAH

MFICAH

MTDTAG

MFDTAG

MTDCAH

MFDCAH

LDHU

HABSADD

instruction for DMA cache synchronization SYNCDMA will be executed as a null instruction. The W90210F CPU core does not snoop the external bus to check the coherence of the cache. To ensure that the contents of the memory remain consistent, devices outside the W90210F CPU can access only non-cacheable memory. FLUSH and purge cache instructions will flush the internal cache only. The W90210F will not broadcast a flush or purge operation to the secondary cache or other bus master (if any).

FICE and FDCE are implemented as described below.

• FICE will flush all instruction cache entries. All instruction entries become invalid after the execution of

FICE.

• FDCE is used to flush an individual cache entry. This instruction causes dirty data to be written back

to memory.

The data cache in the W90210F has 2 x 64 entries. To flush the entire data cache, a loop that execute a flush to a single entry can be used to flush the entire data cache.

Instruction Execution result

Table 5.9 Cache-related instructions and execution results

5.3.3 PA-RISC multimedia extension instruction set

The PA-RISC Multimedia extensions consists of a set of instructions which speed up the execution of common operations found in multimedia applications. Multimedia instructions perform multiple parallel operations in a single cycle.

Instruction Description

Table 5.10 PA-RISC multimedia instructions

5.3.4 DIAG instruction

DIAG instructions are a special instruction format defined by PA-RISC; the functions of these instructions depend on the specific implementation. These instructions are used to program special control registers in the W90K that are not visible in the PA-RISC architecture.

The DIAG instruction syntax is not supported by the assembler. A special macro file provided by Winbond must be included in user programs. The macro converts DIAG assembly instructions into a format recognized by the assembler. With the help of this file, users can employ the DIAG syntax described below for programming.

Instruction Description

Force W90210F CPU enter the HALT state Copies value into a specified AIR from a general register Copies value into a general register from AIR register Copies value into a specified Instruction Tag from a general register Copies value into a general register from a instruction tag Copies value into a specified Instruction cache from a general register Copies value into a general register from a instruction cache entry Copies value into a specified data Tag from a general register Copies value into a general register from a data tag Copies value into a specified data cache from a general register Copies value into a general register from a data cache entry Load halfword and unpack Halfword absolute and add

The above information is the exclusive intellectual property of Winbond Electronics Corp. and shall not be disclosed, distributed or reproduced without permission from Winbond.

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W90210F

Table 5.11 DIAG instructions

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The above information is the exclusive intellectual property of Winbond Electronics Corp. and shall not be disclosed, distributed or reproduced without permission from Winbond.

W90210F

5.4. Debug Special Function Unit

The debug special function unit is an optional, architected SFU which provides hardware assistance for software debugging using breakpoints. The debug SFU is currently provided in the W90210F CPU core. The debug SFU supports two sets of registers for both data breakpoints and instruction breakpoints.

For the instruction debug trap, the trapping address is stored in the interruption instruction address offset queue (IIAOQ). For the data debug trap, the trapping address is stored in the interruption offset register (IOR).

The e bit in each IBAMR determines whether this instruction breakpoint is enabled. If the e bit is 1, any attempt to execute an instruction (including nullified instructions) at an address matching the corresponding IBAOR will cause an instruction debug trap. If the e bit is 0, that instruction breakpoint is disabled.

Instruction Breakpoint Address Offset Register (IBAOR0, IBAOR1):

0 31

address offset

IBAOR

Instruction Breakpoint Address Mask Register (IBAMR0, IBAMR1):

0 31

1 7 8

maskrve

IBAMR

Data Breakpoint Address Offset Register (DBAOR0, DBAOR1):

0 31

address offset

DBAOR

Data Breakpoint Address Mask Register (DBAMR0, DBAMR1):

0 31

1 2 7 8

r w rv

DBAMR

Figure 5.12 Debug SFU registers

mask

The r and w bits in each DBAMR determine the type of access this data breakpoint is enabled for. If the r bit is 1, any non-nullified load or semaphore instruction to an address matching the corresponding DBAOR will cause a data debug trap. If the w bit is 1, any non-nullified store or semaphore instruction or cache purge operation to an address matching the corresponding DBAOR will cause a data debug trap. If the r and w bits are both 0, the data breakpoint is disabled.

For the control of the debug SFU, three bits are added to the PSW register.

Debug Trap Enable Bit (G): Bit 25 of the PSW is defined as the G-bit- the debug trap enable bit. When the G-bit is

1, the data debug trap and instruction debug trap are enabled; when 0, the traps are disabled. The G-bit is set to 0 on interruptions.

Data Debug Trap disable Bit (Y): Bit 0 of the PSW is defined as the Y-bit. The Y-bit is set to 0 after the execution of

each instruction, except for RFI and RFIR instructions which may set it to 1. When 1, data debug traps are disabled.

Instruction Debug Trap disable Bit (Z): Bit 1 of the PSW is defined as the Z-bit. The Z-bit is set to 0 after the

execution of each instruction, except for RFI and RFIR instructions which may set it to 1. When 1, instruction debug traps are disabled.

In addition, CCR bits 16- 23 are used as enable/disable bits for SFUs 0- 7. The debug SFU will use bit 17. When bit 17 is enabled, the SFU #1 instructions will operate normally, but when disabled, all SFU #1 instructions will take an assist emulation trap.

Two new exceptions are added to the architecture- one for instruction debugging and one for data debugging.

Instruction Debug Trap (30): Interruption #30 is now defined as the instruction debug trap. This trap belongs to

group 3.

Data Debug Trap (31): Interruption #31 is defined as the data debug trap. This trap belongs to group3.

Following instructions are added for the debug SFU.

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The above information is the exclusive intellectual property of Winbond Electronics Corp. and shall not be disclosed, distributed or reproduced without permission from Winbond.

W90210F

Mnemonic

Description

Operation

MTDBAO

Move to data breakpoint address offset register

DBAOR[t]←GR[r]

MFDBAO

Move from data breakpoint address offset register

MTDBAM

Move to data breakpoint address mask register

MFDBAM

Move from data breakpoint address mask register

MTIBAO

Move to instruction breakpoint address offset register

MFIBAO

Move from instruction breakpoint address offset register

MTIBAM

Move to instruction breakpoint address mask register

MFIBAM

Move from instruction breakpoint address mask register

DEBUGID

Debug SFU identify

X'00000000

Memory Address Space

X'EFFFFFFF

X'F0000000

I/O Address Space

X'FFFFFFFF

GR[t]←DBAOR[r] DBAMR[t]←GR[r] GR[t]←DBAMR[r] IBAOR[t]←GR[r] GR[t]←IBAOR[r] IBAMR[t]←GR[r] GR[t]←IBAMR[r] GR[t]←id number

Table 5.13 Debug SFU instructions

5.5 Addressing and access control

The W90210F implements real mode addressing. The total addressable space for the W90210F is 4 GB. Objects in the memory and I/O system are addressed using 32-bit absolute addresses. An absolute pointer is a 32-bit unsigned integer whose value is the address of the lowest addressed byte of the operand it designates. The address mapping is same as that specified by the PA-RISC architecture.

5.5.1 Memory and I/O space

Figure 5.16 Memory and I/O addresses

Figure 5.16 shows the memory and I/O address space allocation.

Total memory address space available is (4 GB-256 MB). Total addressable I/O space is 256 MB.

Program address for I/O: Fxxxxxxx

W90210F CPU core output address: 0xxxxxxx

5.5.2 RESET addresses

The initial instruction address after a hardware reset is not defined in the PA-RISC architecture. Two reset addresses are provided for W90210F CPU core. W90210F CPU core will sample the input pin "PA/486#" at the trailing edge of RESET to determine the initial instruction address. When PA/486# pin is low, the initial address will be 000FFFF0; when PA/486# is high, it will be EFFFFFF0. This pointer ensures that the program starts execution from ROM space when used in an X86-compatible board. W90210F CPU core has an internal pull down resistor that will set W90210F CPU to generate X86-like initial address if the PA/486# is left unconnected.

For W90210F, the reset address is always EFFFFFF0.

5.5.3 Access control

Every instruction is fetched and executed at one of four privilege levels (numbered 0,1 2, 3) with 0 being the most privileged. The privilege level is kept in the bits 30 and 31 of the current instruction's address. Base relative branch instructions (BV, BE and BLE) will demote privilege level to any non zero value, if it changes it. GATEWAY instruction promotes the privilege level to 0. Other branch instructions have word offset only and will not change privilege level.

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The above information is the exclusive intellectual property of Winbond Electronics Corp. and shall not be disclosed, distributed or reproduced without permission from Winbond.

W90210F

5.6 Interruptions

11High-priority machine check

Power failure interrupt

23Recovery counter trap

External interrupt

Low-priority machine check

Instruction debug trap

Illegal instruction trap

BREAK instruction trap

Privileged operation trap

311Privileged register trap

Overflow trap

Conditional trap

Data debug trap

Assist emulation trap

Higher-privilege transfer trap

424Lower-privilege transfer trap

Taken branch trap

Interruptions are anomalies that occur during instruction processing causing the flow control to be passed to an interruption handling routine. The interruptions are categorized into four groups based on their priorities. Interruption numbers in table 5.17 are the individual vector numbers that determine which interruption handler is invoked for each interruption. The group numbers determine when the particular interruption will be processed during the course of instruction execution. The order the interruptions are listed within each group determines the priority of simultaneous interruptions(from highest to lowest).

Group interruption number Interruption

Table 5.17 Interruption number

Interruption handler routine begins execution at the address given by:

Interruption Vector Address + (32*interruption_number)

However, handler of HPMC will start at 'initial address + 4', where 'initial address is the first instruction address issued by W90K after RESET. There are two initial address (determined by PA/486#) , X'000FFFF0 or X'EFFFFFF0. HMPC handler will start from either X'000FFFF4 or X'EFFFFFF4. This arrangement is to ensure that HPMC handler will start first at a ROM address that is more reliable than DRAM.

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