:orphan:
.. raw:: html
.. dtcompatible:: st,stm32-fmc-nor-psram
.. _dtbinding_st_stm32_fmc_nor_psram:
st,stm32-fmc-nor-psram
######################
Vendor: :ref:`STMicroelectronics `
Description
***********
.. code-block:: none
STM32 Flexible Memory Controller (NOR Flash/PSRAM/SRAM controller).
The FMC generates the appropriate signal timings to drive the
following types of memories:
* Asynchronous SRAM and ROM
- 8 bits
- 16 bits
- 32 bits
* PSRAM (Cellular RAM)
- Asynchronous mode
- Burst mode for synchronous accesses with configurable option to split burst
access when crossing boundary page for CRAM 1.5.
- Multiplexed or non-multiplexed
* NOR Flash memory
- Asynchronous mode
- Burst mode for synchronous accesses
- Multiplexed or non-multiplexed
A unique Chip Select signal (NE) is used per bank. All the other
signals (addresses, data and control) are shared. A wide range of
devices is supported through programmable timings.
Refer to the reference manual for more details.
The FMC NOR/PSRAM controller is defined below the FMC node and banks are
defined as child nodes of the FMC NOR/PSRAM controller node.
You can enable the controller in devicetree as follows:
&fmc {
status = "okay";
pinctrl-0 = <&fmc_nwe_pd5 &fmc_noe_pd4 ...>;
pinctrl-names = "default";
sram {
status = "okay";
compatible = "st,stm32-fmc-nor-psram";
label = "STM32_FMC_NOR_PSRAM";
#address-cells = <1>;
#size-cells = <0>;
sram2@2 {
reg = <0x2>;
st,control = ;
st,timing = <4 2 3 0 16 17 STM32_FMC_ACCESS_MODE_A>;
};
};
};
Use constants defined in dt-bindings/memory-controller/stm32-fmc-nor-psram.h.
Properties
**********
Top level properties
====================
These property descriptions apply to "st,stm32-fmc-nor-psram"
nodes themselves. This page also describes child node
properties in the following sections.
.. tabs::
.. group-tab:: Node specific properties
Properties not inherited from the base binding file.
(None)
.. group-tab:: Deprecated node specific properties
Deprecated properties not inherited from the base binding file.
(None)
.. group-tab:: Base properties
Properties inherited from the base binding file, which defines
common properties that may be set on many nodes. Not all of these
may apply to the "st,stm32-fmc-nor-psram" compatible.
.. list-table::
:widths: 1 1 4
:header-rows: 1
* - Name
- Type
- Details
* - ``label``
- ``string``
- .. code-block:: none
Human readable string describing the device (used as device_get_binding() argument)
This property is **required**.
See :ref:`zephyr:dt-important-props` for more information.
* - ``#address-cells``
- ``int``
- .. code-block:: none
number of address cells in reg property
This property is **required**.
Constant value: ``1``
* - ``#size-cells``
- ``int``
- .. code-block:: none
number of size cells in reg property
This property is **required**.
* - ``status``
- ``string``
- .. code-block:: none
indicates the operational status of a device
Legal values: ``'ok'``, ``'okay'``, ``'disabled'``, ``'reserved'``, ``'fail'``, ``'fail-sss'``
See :ref:`zephyr:dt-important-props` for more information.
* - ``compatible``
- ``string-array``
- .. code-block:: none
compatible strings
This property is **required**.
See :ref:`zephyr:dt-important-props` for more information.
* - ``reg``
- ``array``
- .. code-block:: none
register space
See :ref:`zephyr:dt-important-props` for more information.
* - ``reg-names``
- ``string-array``
- .. code-block:: none
name of each register space
* - ``interrupts``
- ``array``
- .. code-block:: none
interrupts for device
See :ref:`zephyr:dt-important-props` for more information.
* - ``interrupts-extended``
- ``compound``
- .. code-block:: none
extended interrupt specifier for device
* - ``interrupt-names``
- ``string-array``
- .. code-block:: none
name of each interrupt
* - ``interrupt-parent``
- ``phandle``
- .. code-block:: none
phandle to interrupt controller node
* - ``clocks``
- ``phandle-array``
- .. code-block:: none
Clock gate information
* - ``clock-names``
- ``string-array``
- .. code-block:: none
name of each clock
* - ``dmas``
- ``phandle-array``
- .. code-block:: none
DMA channels specifiers
* - ``dma-names``
- ``string-array``
- .. code-block:: none
Provided names of DMA channel specifiers
* - ``io-channels``
- ``phandle-array``
- .. code-block:: none
IO channels specifiers
* - ``io-channel-names``
- ``string-array``
- .. code-block:: none
Provided names of IO channel specifiers
* - ``mboxes``
- ``phandle-array``
- .. code-block:: none
mailbox / IPM channels specifiers
* - ``mbox-names``
- ``string-array``
- .. code-block:: none
Provided names of mailbox / IPM channel specifiers
* - ``wakeup-source``
- ``boolean``
- .. code-block:: none
Property to identify that a device can be used as wake up source.
When this property is provided a specific flag is set into the
device that tells the system that the device is capable of
wake up the system.
Wake up capable devices are disabled (interruptions will not wake up
the system) by default but they can be enabled at runtime if necessary.
* - ``power-domain``
- ``phandle``
- .. code-block:: none
Power domain the device belongs to.
The device will be notified when the power domain it belongs to is either
suspended or resumed.
Child node properties
=====================
.. list-table::
:widths: 1 1 4
:header-rows: 1
* - Name
- Type
- Details
* - ``reg``
- ``int``
- This property is **required**.
See :ref:`zephyr:dt-important-props` for more information.
* - ``st,control``
- ``array``
- .. code-block:: none
SRAM/NOR-Flash control register (FMC_BCRx).
Contains control information of each memory bank,
used for SRAMs, PSRAM and NOR Flash memories.
Expected fields, in order:
* MUXEN - Address/data multiplexing enable bit.
* MTYP - Memory type.
* MWID - Memory data bus width.
* FACCEN - Flash access enable.
* BURSTEN - Burst enable bit.
* WAITPOL - Wait signal polarity bit.
* WAITCFG - Wait timing configuration.
* WREN - Write enable bit.
* WAITEN - Wait enable bit.
* EXTMOD - Extended mode enable.
If set, then 'st,timing-ext' shall be provided.
* ASYNCWAIT - Wait signal during asynchronous transfers.
* CPSIZE - Cellular RAM (CRAM) 1.5 Page Size.
* CBURSTRW - Write burst enable.
* CCLKEN - Continuous Clock Enable.
* WFDIS - Write FIFO Disable.
* BMAP - FMC bank mapping.
This property is **required**.
* - ``st,timing``
- ``array``
- .. code-block:: none
SRAM/NOR-Flash (read) timing register (FMC_BTRx).
If the EXTMOD is set (see control register FMC_BCRx), then
FMC_BTRx register is partitioned for write and read access.
That means, use this property to configure read accesses and
'st,timing-ext' to configure write accesses.
Expected fields, in order:
* ADDSET - Address setup phase duration.
Number of HCLK cycles to configure the duration of
the address setup time. This parameter can be a value
between Min_Data = 0 and Max_Data = 15.
Note: Not used with synchronous NOR Flash memories.
* ADDHLD - Address-hold phase duration.
Number of HCLK cycles to configure the duration of
the address hold time. This parameter can be a value
between Min_Data = 1 and Max_Data = 15.
Note: Not used with synchronous NOR Flash memories.
* DATAST - Data-phase duration.
Number of HCLK cycles to configure the duration of
the data setup time. This parameter can be a value
between Min_Data = 1 and Max_Data = 255.
Note: Used for SRAMs, ROMs and asynchronous multiplexed
NOR Flash memories.
* BUSTURN - Bus turnaround phase duration.
Number of HCLK cycles to configure the duration of
the bus turnaround. This parameter can be a value
between Min_Data = 0 and Max_Data = 15.
Note: Only used for multiplexed NOR Flash memories.
* CLKDIV - Clock divide ratio (for FMC_CLK signal).
Period of CLK clock output signal, expressed in number of
HCLK cycles. This parameter can be a value
between Min_Data = 2 and Max_Data = 16.
Note: Not used for asynchronous NOR Flash, SRAM or ROM
accesses.
* DATLAT - Data latency for synchronous memory.
Number of memory clock cycles to issue to the memory
before getting the first data.
The value depends on the memory type as shown below:
- It must be set to 0 in case of a CRAM
- It is don't care in asynchronous NOR, SRAM or ROM accesses
- It may assume a value between Min_Data = 2 and Max_Data = 17
in NOR Flash memories with synchronous burst mode enable
* ACCMOD - Access mode.
See access mode defines
in dt-bindings/memory-controller/stm32-fmc-nor-psram.h.
This property is **required**.
* - ``st,timing-ext``
- ``array``
- .. code-block:: none
SRAM/NOR-Flash (write) timing register (FMC_BWTRx).
Expected fields, in order:
* ADDSET - Address setup phase duration.
Reset state: 15 (0xF).
* ADDHLD - Address-hold phase duration.
Reset state: 15 (0xF).
* DATAST - Data-phase duration.
Reset state: 255 (0xFF).
* BUSTURN - Bus turnaround phase duration.
Reset state: 15 (0xF).
* ACCMOD - Access mode.
Reset state: 0 (0x0).
Refer to 'st,timing' for detailed field descriptions.
This property is applied only when EXTMOD is set
(see control register FMC_BCRx).
If absent, then reset state values are used.
Default value: ``[15, 15, 255, 15, 0]``