# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
%YAML 1.2
---
$id: http://devicetree.org/schemas/memory-controllers/ti,gpmc-child.yaml#
$schema: http://devicetree.org/meta-schemas/core.yaml#
title: Texas Instruments GPMC Bus Child Nodes
maintainers:
- Tony Lindgren <tony@atomide.com>
- Roger Quadros <rogerq@kernel.org>
description:
This binding is meant for the child nodes of the GPMC node. The node
represents any device connected to the GPMC bus. It may be a Flash chip,
RAM chip or Ethernet controller, etc. These properties are meant for
configuring the GPMC settings/timings and will accompany the bindings
supported by the respective device.
properties:
reg: true
# GPMC Timing properties for child nodes. All are optional and default to 0.
gpmc,sync-clk-ps:
description: Minimum clock period for synchronous mode
default: 0
# Chip-select signal timings corresponding to GPMC_CONFIG2:
gpmc,cs-on-ns:
description: Assertion time
default: 0
gpmc,cs-rd-off-ns:
description: Read deassertion time
default: 0
gpmc,cs-wr-off-ns:
description: Write deassertion time
default: 0
# ADV signal timings corresponding to GPMC_CONFIG3:
gpmc,adv-on-ns:
description: Assertion time
default: 0
gpmc,adv-rd-off-ns:
description: Read deassertion time
default: 0
gpmc,adv-wr-off-ns:
description: Write deassertion time
default: 0
gpmc,adv-aad-mux-on-ns:
description: Assertion time for AAD
default: 0
gpmc,adv-aad-mux-rd-off-ns:
description: Read deassertion time for AAD
default: 0
gpmc,adv-aad-mux-wr-off-ns:
description: Write deassertion time for AAD
default: 0
# WE signals timings corresponding to GPMC_CONFIG4:
gpmc,we-on-ns:
description: Assertion time
default: 0
gpmc,we-off-ns:
description: Deassertion time
default: 0
# OE signals timings corresponding to GPMC_CONFIG4:
gpmc,oe-on-ns:
description: Assertion time
default: 0
gpmc,oe-off-ns:
description: Deassertion time
default: 0
gpmc,oe-aad-mux-on-ns:
description: Assertion time for AAD
default: 0
gpmc,oe-aad-mux-off-ns:
description: Deassertion time for AAD
default: 0
# Access time and cycle time timings (in nanoseconds) corresponding to
# GPMC_CONFIG5:
gpmc,page-burst-access-ns:
description: Multiple access word delay
default: 0
gpmc,access-ns:
description: Start-cycle to first data valid delay
default: 0
gpmc,rd-cycle-ns:
description: Total read cycle time
default: 0
gpmc,wr-cycle-ns:
description: Total write cycle time
default: 0
gpmc,bus-turnaround-ns:
description: Turn-around time between successive accesses
default: 0
gpmc,cycle2cycle-delay-ns:
description: Delay between chip-select pulses
default: 0
gpmc,clk-activation-ns:
description: GPMC clock activation time
default: 0
gpmc,wait-monitoring-ns:
description: Start of wait monitoring with regard to valid data
default: 0
# Boolean timing parameters. If property is present, parameter is enabled
# otherwise disabled.
gpmc,adv-extra-delay:
description: ADV signal is delayed by half GPMC clock
type: boolean
gpmc,cs-extra-delay:
description: CS signal is delayed by half GPMC clock
type: boolean
gpmc,cycle2cycle-diffcsen:
description: |
Add "cycle2cycle-delay" between successive accesses
to a different CS
type: boolean
gpmc,cycle2cycle-samecsen:
description: |
Add "cycle2cycle-delay" between successive accesses
to the same CS
type: boolean
gpmc,oe-extra-delay:
description: OE signal is delayed by half GPMC clock
type: boolean
gpmc,we-extra-delay:
description: WE signal is delayed by half GPMC clock
type: boolean
gpmc,time-para-granularity:
description: Multiply all access times by 2
type: boolean
# The following two properties are applicable only to OMAP3+ and AM335x:
gpmc,wr-access-ns:
description: |
In synchronous write mode, for single or
burst accesses, defines the number of
GPMC_FCLK cycles from start access time
to the GPMC_CLK rising edge used by the
memory device for the first data capture.
default: 0
gpmc,wr-data-mux-bus-ns:
description: |
In address-data multiplex mode, specifies
the time when the first data is driven on
the address-data bus.
default: 0
# GPMC chip-select settings properties for child nodes. All are optional.
gpmc,burst-length:
description: Page/burst length.
$ref: /schemas/types.yaml#/definitions/uint32
enum: [0, 4, 8, 16]
default: 0
gpmc,burst-wrap:
description: Enables wrap bursting
type: boolean
gpmc,burst-read:
description: Enables read page/burst mode
type: boolean
gpmc,burst-write:
description: Enables write page/burst mode
type: boolean
gpmc,device-width:
description: |
Total width of device(s) connected to a GPMC
chip-select in bytes. The GPMC supports 8-bit
and 16-bit devices and so this property must be
1 or 2.
$ref: /schemas/types.yaml#/definitions/uint32
enum: [1, 2]
default: 1
gpmc,mux-add-data:
description: |
Address and data multiplexing configuration.
Valid values are
0 for Non multiplexed mode
1 for address-address-data multiplexing mode and
2 for address-data multiplexing mode.
$ref: /schemas/types.yaml#/definitions/uint32
enum: [0, 1, 2]
gpmc,sync-read:
description: |
Enables synchronous read. Defaults to asynchronous
is this is not set.
type: boolean
gpmc,sync-write:
description: |
Enables synchronous writes. Defaults to asynchronous
is this is not set.
type: boolean
gpmc,wait-pin:
description: |
Wait-pin used by client. Must be less than "gpmc,num-waitpins".
$ref: /schemas/types.yaml#/definitions/uint32
ti,wait-pin-polarity:
description: |
Set the desired polarity for the selected wait pin.
0 for active low, 1 for active high.
$ref: /schemas/types.yaml#/definitions/uint32
enum: [0, 1]
gpmc,wait-on-read:
description: Enables wait monitoring on reads.
type: boolean
gpmc,wait-on-write:
description: Enables wait monitoring on writes.
type: boolean
required:
- reg
# the GPMC child will have its own native properties
additionalProperties: true