Flash Controller HWIP Technical Specification

Overview

This document describes the flash controller functionality. The flash controller is broken down into 3 major components

  • Open source flash controller
  • Closed source vendor flash wrapper
  • Closed source vendor flash module

A breakdown of the 3 can be seen below Flash High Level Boundaries

This open source flash controller is divided into two partitions.

  • Flash protocol controller
  • Flash physical controller

The remaining document focuses primarily on the function of these blocks.

This module conforms to the Comportable guideline for peripheral functionality. See that document for integration overview within the broader top level system.

Features

Flash Protocol Controller Features

The flash protocol controller interfaces with software and other hardware components in the system (such as life cycle, key manager and OTP). Regardless of the flash size underneath, the flash controller maintains the same data resolution as the bus and processor (default 4B). The flash physical controller (see section below) is then responsible for bridging that size gap between the default data resolution and the actual flash memory.

The protocol controller currently supports the following features:

  • Controller initiated read, program and erase of flash.
    • Erase can be either of a page, or an entire bank.
  • Support for differentiation between informational and data flash partitions.
  • Parameterized support for burst program / read, up to 64B.
    • Longer programs / reads are supported, however the protocol controller will directly back-pressure the bus if software supplies more data than can be consumed, or if software reads more than there is data available.
    • Software can also choose to operate by polling the current state of the FIFO or through FIFO interrupts (empty / full / level).
  • Flash memory protection at page boundaries.
  • Life cycle RMA entry.
  • Key manager secret seeds that are inaccessible to software.
  • Features to be added if required
    • Program verification
      • may not be required if flash memory supports alternative mechanisms of verification.
    • Erase verification
      • may not be required if flash memory supports alternative mechanisms of verification.
    • Flash redundant pages
      • Flash may contain additional pages used to remap broken pages for yield recovery.
      • The storage, loading and security of redundant pages may also be implemented in the physical controller or flash memory.

Features to be implemented

  • Ability to access multiple types of information partition.
    • This feature is pending software / vendor discussions.
  • Ability to access flash metadata bits (see flash ECC)
    • This feature is pending software discussions.

Flash Physical Controller Features

The flash physical controller wraps the actual flash memory and translates both host and controller initiated requests into low level flash transactions.

The physical controller supports the following features

  • Multiple banks of flash memory
  • For each flash bank, parameterized support for number of flash pages (default to 256)
  • For each flash page, parameterized support for number of words and word size (default to 128 words of 8-bytes each)
  • Data and informational partitions within each bank of flash memory
  • Arbitration between host requests and controller requests at the bank level
    • Host requests are always favored, however the controller priority can escalate if it repeatedly loses arbitration
    • Since banks are arbitrated independently and transactions may take different amounts of times to complete, the physical controller is also responsible for ensuring in-order response to both the controller and host.
  • Flash read stage
    • Each bank maintains a parameterizable number of read buffers in front of the flash memory (default to 4).
    • The read buffers behave as miniature read-only-caches to store flash data when flash words are greater than bus words.
    • When a program or erase collides with an entry already stored in the read buffer, the buffer contents are invalidated.
      • This situation may arise if a read is followed by a program or erase.
  • Flash program stage
    • Flash data word packing when flash word size is an integer multiple of bus word size.
  • Flash scrambling
    • Flash supports XEX scrambling using the prince cipher

Features to be implemented

  • Flash scrambling
    • Scrambling is optional based on page boundaries and is configurable by software
  • Flash ECC
    • Flash supports SECDED on the flash word boundary, the ECC bits are stored in the metadata bits and are not normally visible to software.
    • A feature is under consideration to expose the metadata bits to the flash protocol controller.
    • ECC is optional based on page boudaries and is configurable by software

Flash Memory Overview

Unlike sram, flash memory is not typically organized as a contiguous block of generic storage. Instead it is organized into data partitions and information partitions.

The data partition holds generic data like a generic memory would. The information partition holds metadata about the data partition as well design specific secret data. This includes but is not limited to:

  • Redundancy information.
  • Manufacturer specific information.
  • Manufacturer flash timing information.
  • Design specific unique seeds.

Note, there can be more than one information partition, and none of them are required to be the same size as the data partition. See the diagram below for an illustrative example. Flash Example Partition

Which type of partition is accessed is controlled through the CONTROL.PARTITION_SEL field. The current flash controller implements one type of information partition and thus is controlled by 1 bit only. This may change in the future.

Lastly, while the different partitions may be identical in some attributes, they are different in others.

  • All types of partitions must have the same page size and word size; however they are not required to have the same number of pages, thus some partitions may be larger and others smaller.
  • All types of partitions obey the same program and erase rules :
    • A bit cannot be programmed back to 1 once it has been programmed to 0.
    • Only erase can restore a bit to 1 under normal circumstances.
  • Data partitions can be directly read by software and other hardware hosts, while information partitions can only be read by the flash controller

By default, this design assumes 1 type of information partition and 4 pages per type of information partition.

Secret Information Partitions

Two information partition pages in the design hold secret seeds for the key manager. These pages, when enabled by life cycle and otp, are read upon flash controller initialization (no software configuration is required). The read values are then fed to the key manager for later processing. There is a page for creator and a page for the owner.

The seed pages are read under the following initialization conditions:

  • life cycle sets provision enable

Theory of Operation

Block Diagram

Flash Block Diagram

Flash Protocol Controller

The Flash Protocol Controller sits between the host software interface, other hardware components and the flash physical controller. Its primary functions are two fold

  • Translate software program, erase and read requests into a high level protocol for the actual flash physical controller
  • Act as communication interface between flash and other components in the system, such as life cycle and key manager.

The flash protocol controller is not responsible for the detailed timing and waveform control of the flash, nor is it responsible for data scrambling and reliability metadata such as parity and ECC. Instead, it maintains FIFOs / interrupts for the software to process data, as well as high level abstraction of region protection controls and error handling.

The flash controller selects requests between the software and hardware interfaces. By default, the hardware interfaces have precendence and are used to read out seed materials from flash. The seed material is read twice to confirm the values are consistent. They are then forwarded to the key manager for processing. During this seed phase, software initiated activities are back-pressured until the seed reading is complete. It is recommended that instead of blindly issuing transactions to the flash controller, the software polls STATUS.INIT_WIP until it is 0.

Once the seed phase is complete, the flash controller switches to the software interface. Software can then read / program / erase the flash as needed.

When an RMA entry request is received from the life cycle manager, the flash controller waits for any pending flash transaction to complete, then switches priority to the hardware interface. The flash controller then initiates RMA entry process and notifies the life cycle controller when it is complete. Unlike the seed phase, after the RMA phase, the flash controller does not grant control back to software as the system is expected to reboot after an RMA attempt.

Memory Protection

Flash memory protection is handled differently depending on what type of partition is accessed.

For data partitions, software can configure a number of memory protection regions such as MP_REGION_CFG0. For each region, software specifies both the beginning page and the number of pages that belong to that region. Software then configures the access privileges for that region. Subsequent accesses are then allowed or denied based on the defined rule set. Similar to RISCV pmp, if two region overlaps, the lower region index has higher priority.

For information partitions, the protection is done per indvidual page. Each page can be configured with access privileges. As a result, software does not need to define a start and end page for information partitions. See BANK0_INFO_PAGE_CFG0 as an example.

Memory Protection for Key Manager and Life Cycle

While memory protection is largely under software control, certain behavior is hardwired to support key manager secret partitions and life cycle functions.

Software can only control the accessibility of the creator secret seed page under the following condition(s):

  • life cycle sets provision enable.
  • otp indicates the seeds are not locked.

Software can only control the accessibility of the owner secret seed page under the following condition(s):

  • life cycle sets provision enable.

During life cycle RMA transition, the software configured memory protection for both data and information partitions is ignored. Instead, the flash controller assumes a default accessibility setting that allows it to secure the chip and transition to RMA.

Flash Physical Controller

The Flash Physical Controller is the wrapper module that contains the actual flash memory instantiation. It is responsible for arbitrating high level protocol commands (such as read, program, erase) as well as any additional security (scrambling) and reliability (ECC) features. The contained vendor wrapper module is then responsible for converting high level commands into low level signaling and timing specific to a particular flash vendor. The vendor wrapper module is also responsible for any BIST, redundancy handling, remapping features or custom configurations required for the flash.

The scramble keys are provided by an external static block such as the OTP.

Flash Scrambling

Flash scrambling is built using the XEX tweakable block cipher.

When a read transaction is sent to flash, the following steps are taken:

  • The tweak is calculated using the transaction address and a secret address key through a galois multiplier.
  • The data content is read out of flash.
  • If the data content is scrambled, the tweak is XOR’d with the scrambled text and then decrypted through the prince block cipher using a secret data key.
  • The output of the prince cipher is XOR’d again with the tweak and the final results are presented
  • If the data content is not scrambled, the prince and XOR steps are skipped and data provided directly back to the requestor.

When a program transaction is sent to flash, the same steps are taken if the address in question has scrambling enabled. During a program, the text is encrypted through the prince block cipher.

Note, at the moment scrambling is enabled on the entire 2nd bank of flash, but in the future will be a page boundary attribute.

Scrambling Consistency

The flash physical controller does not keep a history of when a particular memory location has scrambling enabled or disabled. This means if a memory locaiton was programmed while scrambled, disabling scrambling and then reading it back will result in garbage. Similarly, if a location was programmed while non-scrambled, enabling scrambling and then reading it back will also result in gargabe.

It it thus the programmer’s responsibility to maintain a consistent definition of whether a location is scrambled. It is also highly recommended in a normal use case to setup up scramble and non-scramble regions and not change it further.

Flash Read Pipeline

Since the system host reads directly from the flash for instructions, it is critical to not add significant latency during read, especially if de-scrambling is required. As such, the flash read is actually a two stage pipeline, where each stage can take multiple cycles.

Additionally, since the flash word size is typically larger than the bus word, recently read flash entries are locally cached. The cache behaves as a highly simplified read-only-cache and holds by default 4 flash words per flash bank.

When a read transaction is sent to flash, the following steps are taken:

  • A check is performed against the local cache
    • If there is a hit (either the entry is already in cache, or the entry is currently being processed), the transacton is immediately forwarded to the response queue.
    • If there is not a hit, an entry in the local cache is selected for allocation (round robin arbitration) and a flash read is issued.
  • When the flash read completes, its descrambling attributes are checked:
    • If descrambling is required, the read data begins the descrambling phase - at this time, a new flash read can be issued for the following transaction.
    • if descrambling is not required, the descrambling phase is skipped and the transaction is pushed to the response queue.
  • When the descrambling is complete, the descrambled text is pushed to the response queue.

The following diagram shows how the flash read pipeline timing works. Flash Read Pipeline

In this example, the first two host requests trigger a full sequence. The third host requests immediately hits in the local cache and responds in order after the first two.

Accessing Information Partition

The information partition uses the same address scheme as the data partition - which is directly accessible by software. This means the address of page{N}.word{M} is the same no matter which type of partition is accessed.

Which partition a specific transaction accesses is denoted through a separate field CONTROL.PARTITION_SEL in the CONTROL register. If CONTROL.PARTITION_SEL is set, then the information partition is accessed. If CONTROL.PARTITION_SEL is not set, then the corresponding word in the data partition is accessed.

Flash scrambling, if enabled, also applies to information partitions. However, one TBD feature is related to flash support of life cycle and manufacturing. It may be required for manufacturers to directly inject data into specific pages flash information partitions via die contacts. For these pages, scramble shall be permanently disabled as the manufacturer should not be aware of scrambling functions.

Hardware Interfaces

Referring to the Comportable guideline for peripheral device functionality, the module FLASH_CTRL has the following hardware interfaces defined.

Primary Clock: clk_i

Other Clocks: none

Bus Device Interface: tlul

Bus Host Interface:

Peripheral Pins for Chip IO: none

Interrupts:

Interrupt NameDescription
prog_emptyProgram FIFO empty
prog_lvlProgram FIFO drained to level
rd_fullRead FIFO full
rd_lvlRead FIFO filled to level
op_doneOperation complete
op_errorOperation failed with error

Security Alerts: none

Signals

In addition to the interrupts and bus signals, the tables below lists the flash protocol controller I/Os.

Signal Direction Description
flash_i input Inputs from physical controller, connects to flash_ctrl_o of physical controller.
flash_o output Outputs to physical controller, connects to flash_ctrl_i of physical controller.
otp_i input Inputs from OTP, indicates the locked state of the creator seed page.
lc_i input Inputs from life cycle, indicates RMA intent and provisioning enable.
pwrmgr_i input Inputs from power manager, flash controller initialization request.

Each of flash_i and flash_o is a struct that packs together additional signals, as shown below

Signal Source Destination Description
req protocol controller physical controller Protocol controller initiated transaction
addr protocol controller physical controller Protocol controller initiated transaction address
rd protocol controller physical controller Protocol controller initiated read
prog protocol controller physical controller Protocol controller initiated program
pg_erase protocol controller physical controller Protocol controller initiated page erase
prog_data protocol controller physical controller Protocol controller initiated program data, 1 flash word wide
bk_erase protocol controller physical controller Protocol controller initiated bank erase
rd_done physical controller protocol controller Physical controller read done
prog_done physical controller protocol controller Physical controller program done
erase_done physical controller protocol controller Physical controller erase done
init_busy physical controller protocol controller Physical controller reset release initialization in progress
rd_data physical controller protocol controller Physical Controller read data, 1 flash word wide

The physical controller IOs are listed and described below.

Signal Direction Description
host_req_i input Host initiated direct read, should always be highest priority. Host is only able to perform direct reads
host_addr_i input Address of host initiated direct read
host_req_rdy_o output Host request ready, ‘1’ implies transaction has been accepted, but not necessarily finished
host_req_done_o output Host request completed
host_rdata_o output Host read data, 1 flash word wide
flash_ctrl_i input Inputs from protocol controller, connects to flash_o of protocol controller
flash_ctrl_o output Outputs to protocol controller, connects to flash_i of protcol controller

Design Detials

Flash Protocol Controller Description

The flash protocol controller uses a simple FIFO interface to communicate between the software and flash physical controller. There is a read fifo for read operations, and a program fifo for program operations. Note, this means flash can be read both through the controller and the main bus interface. This may prove useful if the controller wishes to allocate specific regions to HW FSMs only, but is not a necessary feature.

When software initiates a read transaction of a programmable number of flash words, the flash controller will fill up the read FIFO for software to consume. Likewise, when software initiates a program transaction, software will fill up the program FIFO for the controller to consume.

The controller is designed such that the overall number of words in a transaction can significantly exceed the FIFO depth. In the case of read, once the FIFO is full, the controller will cease writing more entries and wait for software to consume the contents (an interrupt will be triggered to the software to alert it to such an event). In the case of program, the controller will stop writing to flash once all existing data is consumed - it will likewise trigger an interrupt to software to prepare more data. See detailed steps in theory of operation. The following is a diagram of the controller construction as well as its over connectivity with the flash module.

Flash Protocol Controller

Host Read

Unlike controller initiated reads, host reads have separate rdy / done signals to ensure transactions can be properly pipelined. As host reads are usually tied to host execution upstream, additional latency can severely harm performance and is not desired. The expected waveform from the perspective of the physical controller is shown below.

The host_req_done_o is always single cycle pulsed and upstream logic is expected to always accept and correctly handle the return. The same cycle the return data is posted a new command / address can be accepted. While the example shows flash reads completing in back to back cycles, this is typically not the case.

Controller Read

Unlike host reads, controller reads are not as performance critical and do not have command / data pipeline requirements. Instead, the protocol controller will hold the read request and address lines until the done is seen. Once the done is seen, the controller then transitions to the next read operation. The expected waveform from the perspective of the physical controller is shown below.

Controller Program

Program behavior is similar to reads. The protocol controller will hold the request, address and data lines until the programming is complete. The expected waveform from the perspective of the physical controller is shown below.

Programmers Guide

Issuing a Controller Read

To issue a flash read, the programmer must

  • Specify the address of the first flash word to read
  • Specify the number of total flash words to read, beginning at the supplied address
  • Specify the operation to be ‘READ’ type
  • Set the ‘START’ bit for the operation to begin

The above fields can be set in the CONTROL and ADDR registers. See library code for implementation.

It is acceptable for total number of flash words to be significantly greater than the depth of the read FIFO. In this situation, the read FIFO will fill up (or hit programmable fill value), pause the flash read and trigger an interrupt to software. Once there is space inside the FIFO, the controller will resume reading until the appropriate number of words have been read. Once the total count has been reached, the flash controller will post OP_DONE in the OP_STATUS register.

Issuing a Controller Program

To program flash, the same procedure as read is followed. However, instead of setting the CONTROL register for read operation, a program operation is selected instead. Software will then fill the program FIFO and wait for the controller to consume this data. Similar to the read case, the controller will automatically stall when there is insufficient data in the FIFO. When all desired words have been programmed, the controller will post OP_DONE in the OP_STATUS register.

Register Table

The flash protocol controller maintains two separate access windows for the FIFO. It is implemented this way because the access window supports transaction back-pressure should the FIFO become full (in case of write) or empty (in case of read).

FLASH_CTRL.INTR_STATE @ + 0x0
Interrupt State Register
Reset default = 0x0, mask 0x3f
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  op_error op_done rd_lvl rd_full prog_lvl prog_empty
BitsTypeResetNameDescription
0rw1c0x0prog_emptyProgram FIFO empty
1rw1c0x0prog_lvlProgram FIFO drained to level
2rw1c0x0rd_fullRead FIFO full
3rw1c0x0rd_lvlRead FIFO filled to level
4rw1c0x0op_doneOperation complete
5rw1c0x0op_errorOperation failed with error


FLASH_CTRL.INTR_ENABLE @ + 0x4
Interrupt Enable Register
Reset default = 0x0, mask 0x3f
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  op_error op_done rd_lvl rd_full prog_lvl prog_empty
BitsTypeResetNameDescription
0rw0x0prog_emptyEnable interrupt when INTR_STATE.prog_empty is set
1rw0x0prog_lvlEnable interrupt when INTR_STATE.prog_lvl is set
2rw0x0rd_fullEnable interrupt when INTR_STATE.rd_full is set
3rw0x0rd_lvlEnable interrupt when INTR_STATE.rd_lvl is set
4rw0x0op_doneEnable interrupt when INTR_STATE.op_done is set
5rw0x0op_errorEnable interrupt when INTR_STATE.op_error is set


FLASH_CTRL.INTR_TEST @ + 0x8
Interrupt Test Register
Reset default = 0x0, mask 0x3f
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  op_error op_done rd_lvl rd_full prog_lvl prog_empty
BitsTypeResetNameDescription
0wo0x0prog_emptyWrite 1 to force INTR_STATE.prog_empty to 1
1wo0x0prog_lvlWrite 1 to force INTR_STATE.prog_lvl to 1
2wo0x0rd_fullWrite 1 to force INTR_STATE.rd_full to 1
3wo0x0rd_lvlWrite 1 to force INTR_STATE.rd_lvl to 1
4wo0x0op_doneWrite 1 to force INTR_STATE.op_done to 1
5wo0x0op_errorWrite 1 to force INTR_STATE.op_error to 1


FLASH_CTRL.CTRL_REGWEN @ + 0xc
Controls the configurability of the CONTROL register. This register ensures the contents of CONTROL cannot be changed by software once a flash operation has begun. It unlocks whenever the existing flash operation completes, regardless of success or error.
Reset default = 0x1, mask 0x1
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  EN
BitsTypeResetNameDescription
0ro0x1ENConfiguration enable. This bit defaults to 1 and is set to 0 by hardware when flash operation is initiated. When the controller completes the flash operation, this bit is set back to 1 to allow software configuration of CONTROL


FLASH_CTRL.CONTROL @ + 0x10
Control register
Reset default = 0x0, mask 0xfff03f1
Register enable = CTRL_REGWEN
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  NUM
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  INFO_SEL PARTITION_SEL ERASE_SEL PROG_SEL OP   START
BitsTypeResetNameDescription
0rw0x0STARTStart flash transaction. This bit shall only be set after the other fields of the CONTROL register and ADDR have been programmed
3:1Reserved
5:4rw0x0OPFlash operation selection
0ReadFlash Read. Read desired number of flash words
1ProgFlash Program. Program desired number of flash words
2EraseFlash Erase Operation. See ERASE_SEL for details on erase operation
Other values are reserved.
6rw0x0PROG_SELFlash program operation type selection
0Normal programNormal program operation to the flash
1Program repairRepair program operation to the flash. Whether this is actually supported depends on the underlying flash memory.
7rw0x0ERASE_SELFlash erase operation type selection
0Page EraseErase 1 page of flash
1Bank EraseErase 1 bank of flash
8rw0x0PARTITION_SELSelects either info or data partition for operation. When 0, select data partition - this is the portion of flash that is accessible both by the host and by the controller. When 1, select info partition - this is the portion of flash that is only accessible by the controller.
9rw0x0INFO_SELInformational partions can have multiple types. This field selects the info type to be accessed.
15:10Reserved
27:16rw0x0NUMNumber of bus words the flash operation should read or program.


FLASH_CTRL.ADDR @ + 0x14
Address for flash operation
Reset default = 0x0, mask 0xffffffff
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START...
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...START
BitsTypeResetNameDescription
31:0rw0x0STARTStart address of a flash transaction. Software should supply the full byte address. The flash controller will then truncate the address as needed. For read operations, the flash controller will truncate to the closest, lower word aligned address. For example, if 0x13 is supplied, the controller will perform a read at address 0x10. Program operations behave similarly, the controller does not have read modified write support. For page erases, the controller will truncate to the closest lower page aligned address. Similarly for bank erases, the controller will truncate to the closest lower bank aligned address.


FLASH_CTRL.REGION_CFG_REGWEN @ + 0x18
Memory region registers configuration enable.
Reset default = 0x1, mask 0x1
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  EN
BitsTypeResetNameDescription
0rw0c0x1ENRegion register write enable. Once set to 0, it can longer be configured to 1
0Region lockedRegion can no longer be configured until next reset
1Region enabledRegion can be configured


FLASH_CTRL.MP_REGION_CFG_0 @ + 0x1c
Memory protection configuration for data partition
Reset default = 0x0, mask 0x3ff1ff1f
Register enable = REGION_CFG_REGWEN
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  SIZE_0   BASE_0...
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...BASE_0   SCRAMBLE_EN_0 ERASE_EN_0 PROG_EN_0 RD_EN_0 EN_0
BitsTypeResetNameDescription
0rw0x0EN_0Region enabled, following fields apply for FLASH_CTRL0
1rw0x0RD_EN_0Region can be read for FLASH_CTRL0
2rw0x0PROG_EN_0Region can be programmed for FLASH_CTRL0
3rw0x0ERASE_EN_0Region can be erased for FLASH_CTRL0
4rw0x0SCRAMBLE_EN_0Region is scramble and ECC enabled. for FLASH_CTRL0
7:5Reserved
16:8rw0x0BASE_0Region base page. Note the granularity is page, not byte or word for FLASH_CTRL0
19:17Reserved
29:20rw0x0SIZE_0Region size in number of pages for FLASH_CTRL0


FLASH_CTRL.MP_REGION_CFG_1 @ + 0x20
Memory protection configuration for data partition
Reset default = 0x0, mask 0x3ff1ff1f
Register enable = REGION_CFG_REGWEN
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  SIZE_1   BASE_1...
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...BASE_1   SCRAMBLE_EN_1 ERASE_EN_1 PROG_EN_1 RD_EN_1 EN_1
BitsTypeResetNameDescription
0rw0x0EN_1Region enabled, following fields apply for FLASH_CTRL1
1rw0x0RD_EN_1Region can be read for FLASH_CTRL1
2rw0x0PROG_EN_1Region can be programmed for FLASH_CTRL1
3rw0x0ERASE_EN_1Region can be erased for FLASH_CTRL1
4rw0x0SCRAMBLE_EN_1Region is scramble and ECC enabled. for FLASH_CTRL1
7:5Reserved
16:8rw0x0BASE_1Region base page. Note the granularity is page, not byte or word for FLASH_CTRL1
19:17Reserved
29:20rw0x0SIZE_1Region size in number of pages for FLASH_CTRL1


FLASH_CTRL.MP_REGION_CFG_2 @ + 0x24
Memory protection configuration for data partition
Reset default = 0x0, mask 0x3ff1ff1f
Register enable = REGION_CFG_REGWEN
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  SIZE_2   BASE_2...
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...BASE_2   SCRAMBLE_EN_2 ERASE_EN_2 PROG_EN_2 RD_EN_2 EN_2
BitsTypeResetNameDescription
0rw0x0EN_2Region enabled, following fields apply for FLASH_CTRL2
1rw0x0RD_EN_2Region can be read for FLASH_CTRL2
2rw0x0PROG_EN_2Region can be programmed for FLASH_CTRL2
3rw0x0ERASE_EN_2Region can be erased for FLASH_CTRL2
4rw0x0SCRAMBLE_EN_2Region is scramble and ECC enabled. for FLASH_CTRL2
7:5Reserved
16:8rw0x0BASE_2Region base page. Note the granularity is page, not byte or word for FLASH_CTRL2
19:17Reserved
29:20rw0x0SIZE_2Region size in number of pages for FLASH_CTRL2


FLASH_CTRL.MP_REGION_CFG_3 @ + 0x28
Memory protection configuration for data partition
Reset default = 0x0, mask 0x3ff1ff1f
Register enable = REGION_CFG_REGWEN
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  SIZE_3   BASE_3...
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...BASE_3   SCRAMBLE_EN_3 ERASE_EN_3 PROG_EN_3 RD_EN_3 EN_3
BitsTypeResetNameDescription
0rw0x0EN_3Region enabled, following fields apply for FLASH_CTRL3
1rw0x0RD_EN_3Region can be read for FLASH_CTRL3
2rw0x0PROG_EN_3Region can be programmed for FLASH_CTRL3
3rw0x0ERASE_EN_3Region can be erased for FLASH_CTRL3
4rw0x0SCRAMBLE_EN_3Region is scramble and ECC enabled. for FLASH_CTRL3
7:5Reserved
16:8rw0x0BASE_3Region base page. Note the granularity is page, not byte or word for FLASH_CTRL3
19:17Reserved
29:20rw0x0SIZE_3Region size in number of pages for FLASH_CTRL3


FLASH_CTRL.MP_REGION_CFG_4 @ + 0x2c
Memory protection configuration for data partition
Reset default = 0x0, mask 0x3ff1ff1f
Register enable = REGION_CFG_REGWEN
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  SIZE_4   BASE_4...
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...BASE_4   SCRAMBLE_EN_4 ERASE_EN_4 PROG_EN_4 RD_EN_4 EN_4
BitsTypeResetNameDescription
0rw0x0EN_4Region enabled, following fields apply for FLASH_CTRL4
1rw0x0RD_EN_4Region can be read for FLASH_CTRL4
2rw0x0PROG_EN_4Region can be programmed for FLASH_CTRL4
3rw0x0ERASE_EN_4Region can be erased for FLASH_CTRL4
4rw0x0SCRAMBLE_EN_4Region is scramble and ECC enabled. for FLASH_CTRL4
7:5Reserved
16:8rw0x0BASE_4Region base page. Note the granularity is page, not byte or word for FLASH_CTRL4
19:17Reserved
29:20rw0x0SIZE_4Region size in number of pages for FLASH_CTRL4


FLASH_CTRL.MP_REGION_CFG_5 @ + 0x30
Memory protection configuration for data partition
Reset default = 0x0, mask 0x3ff1ff1f
Register enable = REGION_CFG_REGWEN
31302928272625242322212019181716
  SIZE_5   BASE_5...
1514131211109876543210
...BASE_5   SCRAMBLE_EN_5 ERASE_EN_5 PROG_EN_5 RD_EN_5 EN_5
BitsTypeResetNameDescription
0rw0x0EN_5Region enabled, following fields apply for FLASH_CTRL5
1rw0x0RD_EN_5Region can be read for FLASH_CTRL5
2rw0x0PROG_EN_5Region can be programmed for FLASH_CTRL5
3rw0x0ERASE_EN_5Region can be erased for FLASH_CTRL5
4rw0x0SCRAMBLE_EN_5Region is scramble and ECC enabled. for FLASH_CTRL5
7:5Reserved
16:8rw0x0BASE_5Region base page. Note the granularity is page, not byte or word for FLASH_CTRL5
19:17Reserved
29:20rw0x0SIZE_5Region size in number of pages for FLASH_CTRL5


FLASH_CTRL.MP_REGION_CFG_6 @ + 0x34
Memory protection configuration for data partition
Reset default = 0x0, mask 0x3ff1ff1f
Register enable = REGION_CFG_REGWEN
31302928272625242322212019181716
  SIZE_6   BASE_6...
1514131211109876543210
...BASE_6   SCRAMBLE_EN_6 ERASE_EN_6 PROG_EN_6 RD_EN_6 EN_6
BitsTypeResetNameDescription
0rw0x0EN_6Region enabled, following fields apply for FLASH_CTRL6
1rw0x0RD_EN_6Region can be read for FLASH_CTRL6
2rw0x0PROG_EN_6Region can be programmed for FLASH_CTRL6
3rw0x0ERASE_EN_6Region can be erased for FLASH_CTRL6
4rw0x0SCRAMBLE_EN_6Region is scramble and ECC enabled. for FLASH_CTRL6
7:5Reserved
16:8rw0x0BASE_6Region base page. Note the granularity is page, not byte or word for FLASH_CTRL6
19:17Reserved
29:20rw0x0SIZE_6Region size in number of pages for FLASH_CTRL6


FLASH_CTRL.MP_REGION_CFG_7 @ + 0x38
Memory protection configuration for data partition
Reset default = 0x0, mask 0x3ff1ff1f
Register enable = REGION_CFG_REGWEN
31302928272625242322212019181716
  SIZE_7   BASE_7...
1514131211109876543210
...BASE_7   SCRAMBLE_EN_7 ERASE_EN_7 PROG_EN_7 RD_EN_7 EN_7
BitsTypeResetNameDescription
0rw0x0EN_7Region enabled, following fields apply for FLASH_CTRL7
1rw0x0RD_EN_7Region can be read for FLASH_CTRL7
2rw0x0PROG_EN_7Region can be programmed for FLASH_CTRL7
3rw0x0ERASE_EN_7Region can be erased for FLASH_CTRL7
4rw0x0SCRAMBLE_EN_7Region is scramble and ECC enabled. for FLASH_CTRL7
7:5Reserved
16:8rw0x0BASE_7Region base page. Note the granularity is page, not byte or word for FLASH_CTRL7
19:17Reserved
29:20rw0x0SIZE_7Region size in number of pages for FLASH_CTRL7


FLASH_CTRL.BANK0_INFO0_PAGE_CFG_0 @ + 0x3c
Memory protection configuration for info partition in bank0, Unlike data partition, each page is individually protected.
Reset default = 0x0, mask 0x1f
Register enable = REGION_CFG_REGWEN
31302928272625242322212019181716
 
1514131211109876543210
  SCRAMBLE_EN_0 ERASE_EN_0 PROG_EN_0 RD_EN_0 EN_0
BitsTypeResetNameDescription
0rw0x0EN_0Region enabled, following fields apply for FLASH_CTRL0
1rw0x0RD_EN_0Region can be read for FLASH_CTRL0
2rw0x0PROG_EN_0Region can be programmed for FLASH_CTRL0
3rw0x0ERASE_EN_0Region can be erased for FLASH_CTRL0
4rw0x0SCRAMBLE_EN_0Region is scramble and ECC enabled. for FLASH_CTRL0


FLASH_CTRL.BANK0_INFO0_PAGE_CFG_1 @ + 0x40
Memory protection configuration for info partition in bank0, Unlike data partition, each page is individually protected.
Reset default = 0x0, mask 0x1f
Register enable = REGION_CFG_REGWEN
31302928272625242322212019181716
 
1514131211109876543210
  SCRAMBLE_EN_1 ERASE_EN_1 PROG_EN_1 RD_EN_1 EN_1
BitsTypeResetNameDescription
0rw0x0EN_1Region enabled, following fields apply for FLASH_CTRL1
1rw0x0RD_EN_1Region can be read for FLASH_CTRL1
2rw0x0PROG_EN_1Region can be programmed for FLASH_CTRL1
3rw0x0ERASE_EN_1Region can be erased for FLASH_CTRL1
4rw0x0SCRAMBLE_EN_1Region is scramble and ECC enabled. for FLASH_CTRL1


FLASH_CTRL.BANK0_INFO0_PAGE_CFG_2 @ + 0x44
Memory protection configuration for info partition in bank0, Unlike data partition, each page is individually protected.
Reset default = 0x0, mask 0x1f
Register enable = REGION_CFG_REGWEN
31302928272625242322212019181716
 
1514131211109876543210
  SCRAMBLE_EN_2 ERASE_EN_2 PROG_EN_2 RD_EN_2 EN_2
BitsTypeResetNameDescription
0rw0x0EN_2Region enabled, following fields apply for FLASH_CTRL2
1rw0x0RD_EN_2Region can be read for FLASH_CTRL2
2rw0x0PROG_EN_2Region can be programmed for FLASH_CTRL2
3rw0x0ERASE_EN_2Region can be erased for FLASH_CTRL2
4rw0x0SCRAMBLE_EN_2Region is scramble and ECC enabled. for FLASH_CTRL2


FLASH_CTRL.BANK0_INFO0_PAGE_CFG_3 @ + 0x48
Memory protection configuration for info partition in bank0, Unlike data partition, each page is individually protected.
Reset default = 0x0, mask 0x1f
Register enable = REGION_CFG_REGWEN
31302928272625242322212019181716
 
1514131211109876543210
  SCRAMBLE_EN_3 ERASE_EN_3 PROG_EN_3 RD_EN_3 EN_3
BitsTypeResetNameDescription
0rw0x0EN_3Region enabled, following fields apply for FLASH_CTRL3
1rw0x0RD_EN_3Region can be read for FLASH_CTRL3
2rw0x0PROG_EN_3Region can be programmed for FLASH_CTRL3
3rw0x0ERASE_EN_3Region can be erased for FLASH_CTRL3
4rw0x0SCRAMBLE_EN_3Region is scramble and ECC enabled. for FLASH_CTRL3


FLASH_CTRL.BANK0_INFO1_PAGE_CFG_0 @ + 0x4c
Memory protection configuration for info partition in bank0, Unlike data partition, each page is individually protected.
Reset default = 0x0, mask 0x1f
Register enable = REGION_CFG_REGWEN
31302928272625242322212019181716
 
1514131211109876543210
  SCRAMBLE_EN_0 ERASE_EN_0 PROG_EN_0 RD_EN_0 EN_0
BitsTypeResetNameDescription
0rw0x0EN_0Region enabled, following fields apply for FLASH_CTRL0
1rw0x0RD_EN_0Region can be read for FLASH_CTRL0
2rw0x0PROG_EN_0Region can be programmed for FLASH_CTRL0
3rw0x0ERASE_EN_0Region can be erased for FLASH_CTRL0
4rw0x0SCRAMBLE_EN_0Region is scramble and ECC enabled. for FLASH_CTRL0


FLASH_CTRL.BANK0_INFO1_PAGE_CFG_1 @ + 0x50
Memory protection configuration for info partition in bank0, Unlike data partition, each page is individually protected.
Reset default = 0x0, mask 0x1f
Register enable = REGION_CFG_REGWEN
31302928272625242322212019181716
 
1514131211109876543210
  SCRAMBLE_EN_1 ERASE_EN_1 PROG_EN_1 RD_EN_1 EN_1
BitsTypeResetNameDescription
0rw0x0EN_1Region enabled, following fields apply for FLASH_CTRL1
1rw0x0RD_EN_1Region can be read for FLASH_CTRL1
2rw0x0PROG_EN_1Region can be programmed for FLASH_CTRL1
3rw0x0ERASE_EN_1Region can be erased for FLASH_CTRL1
4rw0x0SCRAMBLE_EN_1Region is scramble and ECC enabled. for FLASH_CTRL1


FLASH_CTRL.BANK0_INFO1_PAGE_CFG_2 @ + 0x54
Memory protection configuration for info partition in bank0, Unlike data partition, each page is individually protected.
Reset default = 0x0, mask 0x1f
Register enable = REGION_CFG_REGWEN
31302928272625242322212019181716
 
1514131211109876543210
  SCRAMBLE_EN_2 ERASE_EN_2 PROG_EN_2 RD_EN_2 EN_2
BitsTypeResetNameDescription
0rw0x0EN_2Region enabled, following fields apply for FLASH_CTRL2
1rw0x0RD_EN_2Region can be read for FLASH_CTRL2
2rw0x0PROG_EN_2Region can be programmed for FLASH_CTRL2
3rw0x0ERASE_EN_2Region can be erased for FLASH_CTRL2
4rw0x0SCRAMBLE_EN_2Region is scramble and ECC enabled. for FLASH_CTRL2


FLASH_CTRL.BANK0_INFO1_PAGE_CFG_3 @ + 0x58
Memory protection configuration for info partition in bank0, Unlike data partition, each page is individually protected.
Reset default = 0x0, mask 0x1f
Register enable = REGION_CFG_REGWEN
31302928272625242322212019181716
 
1514131211109876543210
  SCRAMBLE_EN_3 ERASE_EN_3 PROG_EN_3 RD_EN_3 EN_3
BitsTypeResetNameDescription
0rw0x0EN_3Region enabled, following fields apply for FLASH_CTRL3
1rw0x0RD_EN_3Region can be read for FLASH_CTRL3
2rw0x0PROG_EN_3Region can be programmed for FLASH_CTRL3
3rw0x0ERASE_EN_3Region can be erased for FLASH_CTRL3
4rw0x0SCRAMBLE_EN_3Region is scramble and ECC enabled. for FLASH_CTRL3


FLASH_CTRL.BANK1_INFO0_PAGE_CFG_0 @ + 0x5c
Memory protection configuration for info partition in bank1, Unlike data partition, each page is individually protected.
Reset default = 0x0, mask 0x1f
Register enable = REGION_CFG_REGWEN
31302928272625242322212019181716
 
1514131211109876543210
  SCRAMBLE_EN_0 ERASE_EN_0 PROG_EN_0 RD_EN_0 EN_0
BitsTypeResetNameDescription
0rw0x0EN_0Region enabled, following fields apply for FLASH_CTRL0
1rw0x0RD_EN_0Region can be read for FLASH_CTRL0
2rw0x0PROG_EN_0Region can be programmed for FLASH_CTRL0
3rw0x0ERASE_EN_0Region can be erased for FLASH_CTRL0
4rw0x0SCRAMBLE_EN_0Region is scramble and ECC enabled. for FLASH_CTRL0


FLASH_CTRL.BANK1_INFO0_PAGE_CFG_1 @ + 0x60
Memory protection configuration for info partition in bank1, Unlike data partition, each page is individually protected.
Reset default = 0x0, mask 0x1f
Register enable = REGION_CFG_REGWEN
31302928272625242322212019181716
 
1514131211109876543210
  SCRAMBLE_EN_1 ERASE_EN_1 PROG_EN_1 RD_EN_1 EN_1
BitsTypeResetNameDescription
0rw0x0EN_1Region enabled, following fields apply for FLASH_CTRL1
1rw0x0RD_EN_1Region can be read for FLASH_CTRL1
2rw0x0PROG_EN_1Region can be programmed for FLASH_CTRL1
3rw0x0ERASE_EN_1Region can be erased for FLASH_CTRL1
4rw0x0SCRAMBLE_EN_1Region is scramble and ECC enabled. for FLASH_CTRL1


FLASH_CTRL.BANK1_INFO0_PAGE_CFG_2 @ + 0x64
Memory protection configuration for info partition in bank1, Unlike data partition, each page is individually protected.
Reset default = 0x0, mask 0x1f
Register enable = REGION_CFG_REGWEN
31302928272625242322212019181716
 
1514131211109876543210
  SCRAMBLE_EN_2 ERASE_EN_2 PROG_EN_2 RD_EN_2 EN_2
BitsTypeResetNameDescription
0rw0x0EN_2Region enabled, following fields apply for FLASH_CTRL2
1rw0x0RD_EN_2Region can be read for FLASH_CTRL2
2rw0x0PROG_EN_2Region can be programmed for FLASH_CTRL2
3rw0x0ERASE_EN_2Region can be erased for FLASH_CTRL2
4rw0x0SCRAMBLE_EN_2Region is scramble and ECC enabled. for FLASH_CTRL2


FLASH_CTRL.BANK1_INFO0_PAGE_CFG_3 @ + 0x68
Memory protection configuration for info partition in bank1, Unlike data partition, each page is individually protected.
Reset default = 0x0, mask 0x1f
Register enable = REGION_CFG_REGWEN
31302928272625242322212019181716
 
1514131211109876543210
  SCRAMBLE_EN_3 ERASE_EN_3 PROG_EN_3 RD_EN_3 EN_3
BitsTypeResetNameDescription
0rw0x0EN_3Region enabled, following fields apply for FLASH_CTRL3
1rw0x0RD_EN_3Region can be read for FLASH_CTRL3
2rw0x0PROG_EN_3Region can be programmed for FLASH_CTRL3
3rw0x0ERASE_EN_3Region can be erased for FLASH_CTRL3
4rw0x0SCRAMBLE_EN_3Region is scramble and ECC enabled. for FLASH_CTRL3


FLASH_CTRL.BANK1_INFO1_PAGE_CFG_0 @ + 0x6c
Memory protection configuration for info partition in bank1, Unlike data partition, each page is individually protected.
Reset default = 0x0, mask 0x1f
Register enable = REGION_CFG_REGWEN
31302928272625242322212019181716
 
1514131211109876543210
  SCRAMBLE_EN_0 ERASE_EN_0 PROG_EN_0 RD_EN_0 EN_0
BitsTypeResetNameDescription
0rw0x0EN_0Region enabled, following fields apply for FLASH_CTRL0
1rw0x0RD_EN_0Region can be read for FLASH_CTRL0
2rw0x0PROG_EN_0Region can be programmed for FLASH_CTRL0
3rw0x0ERASE_EN_0Region can be erased for FLASH_CTRL0
4rw0x0SCRAMBLE_EN_0Region is scramble and ECC enabled. for FLASH_CTRL0


FLASH_CTRL.BANK1_INFO1_PAGE_CFG_1 @ + 0x70
Memory protection configuration for info partition in bank1, Unlike data partition, each page is individually protected.
Reset default = 0x0, mask 0x1f
Register enable = REGION_CFG_REGWEN
31302928272625242322212019181716
 
1514131211109876543210
  SCRAMBLE_EN_1 ERASE_EN_1 PROG_EN_1 RD_EN_1 EN_1
BitsTypeResetNameDescription
0rw0x0EN_1Region enabled, following fields apply for FLASH_CTRL1
1rw0x0RD_EN_1Region can be read for FLASH_CTRL1
2rw0x0PROG_EN_1Region can be programmed for FLASH_CTRL1
3rw0x0ERASE_EN_1Region can be erased for FLASH_CTRL1
4rw0x0SCRAMBLE_EN_1Region is scramble and ECC enabled. for FLASH_CTRL1


FLASH_CTRL.BANK1_INFO1_PAGE_CFG_2 @ + 0x74
Memory protection configuration for info partition in bank1, Unlike data partition, each page is individually protected.
Reset default = 0x0, mask 0x1f
Register enable = REGION_CFG_REGWEN
31302928272625242322212019181716
 
1514131211109876543210
  SCRAMBLE_EN_2 ERASE_EN_2 PROG_EN_2 RD_EN_2 EN_2
BitsTypeResetNameDescription
0rw0x0EN_2Region enabled, following fields apply for FLASH_CTRL2
1rw0x0RD_EN_2Region can be read for FLASH_CTRL2
2rw0x0PROG_EN_2Region can be programmed for FLASH_CTRL2
3rw0x0ERASE_EN_2Region can be erased for FLASH_CTRL2
4rw0x0SCRAMBLE_EN_2Region is scramble and ECC enabled. for FLASH_CTRL2


FLASH_CTRL.BANK1_INFO1_PAGE_CFG_3 @ + 0x78
Memory protection configuration for info partition in bank1, Unlike data partition, each page is individually protected.
Reset default = 0x0, mask 0x1f
Register enable = REGION_CFG_REGWEN
31302928272625242322212019181716
 
1514131211109876543210
  SCRAMBLE_EN_3 ERASE_EN_3 PROG_EN_3 RD_EN_3 EN_3
BitsTypeResetNameDescription
0rw0x0EN_3Region enabled, following fields apply for FLASH_CTRL3
1rw0x0RD_EN_3Region can be read for FLASH_CTRL3
2rw0x0PROG_EN_3Region can be programmed for FLASH_CTRL3
3rw0x0ERASE_EN_3Region can be erased for FLASH_CTRL3
4rw0x0SCRAMBLE_EN_3Region is scramble and ECC enabled. for FLASH_CTRL3


FLASH_CTRL.DEFAULT_REGION @ + 0x7c
Default region permissions
Reset default = 0x0, mask 0xf
31302928272625242322212019181716
 
1514131211109876543210
  SCRAMBLE_EN ERASE_EN PROG_EN RD_EN
BitsTypeResetNameDescription
0rw0x0RD_ENRegion can be read
1rw0x0PROG_ENRegion can be programmed
2rw0x0ERASE_ENRegion can be erased
3rw0x0SCRAMBLE_ENRegion is scramble and ECC enabled


FLASH_CTRL.BANK_CFG_REGWEN @ + 0x80
Bank configuration registers configuration enable.
Reset default = 0x1, mask 0x1
31302928272625242322212019181716
 
1514131211109876543210
  BANK
BitsTypeResetNameDescription
0rw0c0x1BANKBank register write enable. Once set to 0, it can longer be configured to 1
0Bank lockedBank can no longer be configured until next reset
1Bank enabledBank can be configured


FLASH_CTRL.MP_BANK_CFG @ + 0x84
Memory protect bank configuration
Reset default = 0x0, mask 0x3
Register enable = BANK_CFG_REGWEN
31302928272625242322212019181716
 
1514131211109876543210
  ERASE_EN_1 ERASE_EN_0
BitsTypeResetNameDescription
0rw0x0ERASE_EN_0Bank wide erase enable for FLASH_CTRL0
1:1for FLASH_CTRL1


FLASH_CTRL.OP_STATUS @ + 0x88
Flash Operation Status
Reset default = 0x0, mask 0x3
31302928272625242322212019181716
 
1514131211109876543210
  err done
BitsTypeResetNameDescription
0rw0x0doneFlash operation done. Set by HW, cleared by SW
1rw0x0errFlash operation error. Set by HW, cleared by SW


FLASH_CTRL.STATUS @ + 0x8c
Flash Controller Status
Reset default = 0xa, mask 0x1ff1f
31302928272625242322212019181716
  error_addr...
1514131211109876543210
...error_addr   init_wip prog_empty prog_full rd_empty rd_full
BitsTypeResetNameDescription
0ro0x0rd_fullFlash read FIFO full, software must consume data
1ro0x1rd_emptyFlash read FIFO empty
2ro0x0prog_fullFlash program FIFO full
3ro0x1prog_emptyFlash program FIFO empty, software must provide data
4ro0x0init_wipFlash controller undergoing init, inclusive of phy init
7:5Reserved
16:8ro0x0error_addrFlash controller error address.


FLASH_CTRL.PHY_STATUS @ + 0x90
Flash Phy Status
Reset default = 0x6, mask 0x7
31302928272625242322212019181716
 
1514131211109876543210
  prog_repair_avail prog_normal_avail init_wip
BitsTypeResetNameDescription
0ro0x0init_wipFlash phy controller initializing
1ro0x1prog_normal_availNormal program supported
2ro0x1prog_repair_availProgram repair supported


FLASH_CTRL.Scratch @ + 0x94
Flash Controller Scratch
Reset default = 0x0, mask 0xffffffff
31302928272625242322212019181716
data...
1514131211109876543210
...data
BitsTypeResetNameDescription
31:0rw0x0dataFlash ctrl scratch register


FLASH_CTRL.FIFO_LVL @ + 0x98
Programmable depth where FIFOs should generate interrupts
Reset default = 0xf0f, mask 0x1f1f
31302928272625242322212019181716
 
1514131211109876543210
  RD   PROG
BitsTypeResetNameDescription
4:0rw0xfPROGWhen the program FIFO drains to this level, trigger an interrupt. Default value is set such that interrupt does not trigger at reset.
7:5Reserved
12:8rw0xfRDWhen the read FIFO fills to this level, trigger an interrupt. Default value is set such that interrupt does not trigger at reset.


FLASH_CTRL.FIFO_RST @ + 0x9c
Reset for flash controller FIFOs
Reset default = 0x0, mask 0x1
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  EN
BitsTypeResetNameDescription
0rw0x0ENActive high resets for both program and read FIFOs. This is especially useful after the controller encounters an error of some kind. This bit will hold the FIFO in reset as long as it is set.


FLASH_CTRL.prog_fifo @ + 0xa0
1 item wo window
Byte writes are not supported
310
+0xa0 
+0xa4 
 ...
+0x9c 
+0xa0 
Flash program FIFO. The FIFO is 16 entries of 4B flash words. This FIFO can only be programmed by software after a program operation has been initiated via the CONTROL register. This ensures accidental programming of the program FIFO cannot lock up the system.


FLASH_CTRL.rd_fifo @ + 0xa4
1 item ro window
Byte writes are not supported
310
+0xa4 
+0xa8 
 ...
+0xa0 
+0xa4 
Flash read FIFO. The FIFO is 16 entries of 4B flash words