[PATCH 05/10] Remove Non-Volatile Memory Driver chapter
Sebastian Huber
sebastian.huber at embedded-brains.de
Tue Dec 20 13:45:22 UTC 2016
There exists no standard Non-Volatile Memory Driver in the RTEMS code
base.
Close #2851.
---
bsp-howto/index.rst | 1 -
bsp-howto/non_volatile_memory.rst | 217 --------------------------------------
2 files changed, 218 deletions(-)
delete mode 100644 bsp-howto/non_volatile_memory.rst
diff --git a/bsp-howto/index.rst b/bsp-howto/index.rst
index f99118d..d826369 100644
--- a/bsp-howto/index.rst
+++ b/bsp-howto/index.rst
@@ -53,7 +53,6 @@ to the Community Project hosted at http://www.rtems.org.
real_time_clock
ata
ide_controller
- non_volatile_memory
networking
shared_memory_support
frame_buffer
diff --git a/bsp-howto/non_volatile_memory.rst b/bsp-howto/non_volatile_memory.rst
deleted file mode 100644
index e23c162..0000000
--- a/bsp-howto/non_volatile_memory.rst
+++ /dev/null
@@ -1,217 +0,0 @@
-.. comment SPDX-License-Identifier: CC-BY-SA-4.0
-
-.. COMMENT: Written by Eric Norum
-.. COMMENT: COPYRIGHT (c) 1988-2002.
-.. COMMENT: On-Line Applications Research Corporation (OAR).
-.. COMMENT: All rights reserved.
-
-Non-Volatile Memory Driver
-**************************
-
-The Non-Volatile driver is responsible for providing an interface to various
-types of non-volatile memory. These types of memory include, but are not
-limited to, Flash, EEPROM, and battery backed RAM. The capabilities provided
-by this class of device driver are:
-
-- Initialize the Non-Volatile Memory Driver
-
-- Optional Disable Read and Write Handlers
-
-- Open a Particular Memory Partition
-
-- Close a Particular Memory Partition
-
-- Read from a Particular Memory Partition
-
-- Write to a Particular Memory Partition
-
-- Erase the Non-Volatile Memory Area
-
-There is currently only one non-volatile device driver included in the RTEMS
-source tree. The information provided in this chapter is based on drivers
-developed for applications using RTEMS. It is hoped that this driver model
-information can form the basis for a standard non-volatile memory driver model
-that can be supported in future RTEMS distribution.
-
-Major and Minor Numbers
-=======================
-
-The ``major`` number of a device driver is its index in the RTEMS Device
-Address Table.
-
-A ``minor`` number is associated with each device instance managed by a
-particular device driver. An RTEMS minor number is an ``unsigned32`` entity.
-Convention calls dividing the bits in the minor number down into categories
-that specify an area of non-volatile memory and a partition with that area.
-This results in categories like the following:
-
-- ``area`` - indicates a block of non-volatile memory
-
-- ``partition`` - indicates a particular address range with an area
-
-From the above, it should be clear that a single device driver can support
-multiple types of non-volatile memory in a single system. The minor number is
-used to distinguish the types of memory and blocks of memory used for different
-purposes.
-
-Non-Volatile Memory Driver Configuration
-========================================
-
-There is not a standard non-volatile driver configuration table but some fields
-are common across different drivers. The non-volatile memory driver
-configuration table is typically an array of structures with each structure
-containing the information for a particular area of non-volatile memory. The
-following is a list of the type of information normally required to configure
-each area of non-volatile memory.
-
-``memory_type``
- is the type of memory device in this area. Choices are battery backed RAM,
- EEPROM, Flash, or an optional user-supplied type. If the user-supplied
- type is configured, then the user is responsible for providing a set of
- routines to program the memory.
-
-``memory``
- is the base address of this memory area.
-
-``attributes``
- is a pointer to a memory type specific attribute block. Some of the fields
- commonly contained in this memory type specific attribute structure area:
-
- ``use_protection_algorithm``
- is set to TRUE to indicate that the protection (i.e. locking) algorithm
- should be used for this area of non-volatile memory. A particular type
- of non-volatile memory may not have a protection algorithm.
-
- ``access``
- is an enumerated type to indicate the organization of the memory
- devices in this memory area. The following is a list of the access
- types supported by the current driver implementation:
-
- - simple unsigned8
- - simple unsigned16
- - simple unsigned32
- - simple unsigned64
- - single unsigned8 at offset 0 in an unsigned16
- - single unsigned8 at offset 1 in an unsigned16
- - single unsigned8 at offset 0 in an unsigned32
- - single unsigned8 at offset 1 in an unsigned32
- - single unsigned8 at offset 2 in an unsigned32
- - single unsigned8 at offset 3 in an unsigned32
-
- ``depth``
- is the depth of the progamming FIFO on this particular chip. Some
- chips, particularly EEPROMs, have the same programming algorithm but
- vary in the depth of the amount of data that can be programmed in a
- single block.
-
-``number_of_partitions``
- is the number of logical partitions within this area.
-
-``Partitions``
- is the address of the table that contains an entry to describe each
- partition in this area. Fields within each element of this table are
- defined as follows:
-
- ``offset``
- is the offset of this partition from the base address of this area.
-
- ``length``
- is the length of this partition.
-
-By dividing an area of memory into multiple partitions, it is possible to
-easily divide the non-volatile memory for different purposes.
-
-Initialize the Non-Volatile Memory Driver
-=========================================
-
-At system initialization, the non-volatile memory driver's initialization entry
-point will be invoked. As part of initialization, the driver will perform
-whatever initializatin is required on each non-volatile memory area.
-
-The discrete I/O driver may register device names for memory partitions of
-particular interest to the system. Normally this will be restricted to the
-device "/dev/nv_memory" to indicate the entire device driver.
-
-Disable Read and Write Handlers
-===============================
-
-Depending on the target's non-volatile memory configuration, it may be possible
-to write to a status register and make the memory area completely inaccessible.
-This is target dependent and beyond the standard capabilities of any memory
-type. The user has the optional capability to provide handlers to disable and
-enable access to a partiticular memory area.
-
-Open a Particular Memory Partition
-==================================
-
-This is the driver open call. Usually this call does nothing other than
-validate the minor number.
-
-With some drivers, it may be necessary to allocate memory when a particular
-device is opened. If that is the case, then this is often the place to do this
-operation.
-
-Close a Particular Memory Partition
-===================================
-
-This is the driver close call. Usually this call does nothing.
-
-With some drivers, it may be necessary to allocate memory when a particular
-device is opened. If that is the case, then this is the place where that
-memory should be deallocated.
-
-Read from a Particular Memory Partition
-=======================================
-
-This corresponds to the driver read call. After validating the minor number
-and arguments, this call enables reads from the specified memory area by
-invoking the user supplied "enable reads handler" and then reads the indicated
-memory area. When invoked the ``argument_block`` is actually a pointer to the
-following structure type:
-
-.. code-block:: c
-
- typedef struct {
- uint32_t offset;
- void *buffer;
- uint32_t length;
- uint32_t status;
- } Non_volatile_memory_Driver_arguments;
-
-The driver reads ``length`` bytes starting at ``offset`` into the partition and
-places them at ``buffer``. The result is returned in ``status``.
-
-After the read operation is complete, the user supplied "disable reads handler"
-is invoked to protect the memory area again.
-
-Write to a Particular Memory Partition
-======================================
-
-This corresponds to the driver write call. After validating the minor number
-and arguments, this call enables writes to the specified memory area by
-invoking the "enable writes handler", then unprotecting the memory area, and
-finally actually writing to the indicated memory area. When invoked the
-``argument_block`` is actually a pointer to the following structure type:
-
-.. code-block:: c
-
- typedef struct {
- uint32_t offset;
- void *buffer;
- uint32_t length;
- uint32_t status;
- } Non_volatile_memory_Driver_arguments;
-
-The driver writes ``length`` bytes from ``buffer`` and writes them to the
-non-volatile memory starting at ``offset`` into the partition. The result is
-returned in ``status``.
-
-After the write operation is complete, the "disable writes handler" is invoked
-to protect the memory area again.
-
-Erase the Non-Volatile Memory Area
-==================================
-
-This is one of the IOCTL functions supported by the I/O control device driver
-entry point. When this IOCTL function is invoked, the specified area of
-non-volatile memory is erased.
--
1.8.4.5
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