memory_cs - MTD-aware PCMCIA memory card driver
insmod memory_cs.o [pc_debug=n] [mem_speed=n] [word_width=n] [force_size=n]
Memory_cs is the Card Services driver for PCMCIA memory cards, and also provides direct
memory access for other types of cards. It provides character-mode and block-mode for
accessing any card's attribute and common memory address spaces, analogous to /dev/mem.
Memory_cs will allocate a free major device number when it is loaded. It provides two
types of minor devices: "direct" character-mode devices for raw access a card's entire
PCMCIA common and attribute memory spaces, and "indirect" devices for accessing specific
memory partitions via an appropriate Memory Technology Driver. The bitwise layout of
minor device numbers is one memory device. 'x' is set if this is a direct-access device,
'a' is set for attribute memory, and 'rr' is the region number (for indirect devices).
When memory_cs is bound to a card, it will report its major and minor device numbers to
The default memory card initialization script creates character special device files for
the direct common memory and attribute memory devices. It also creates character special
devices for accessing the first attribute and common memory partitions, and a block device
for accessing the first common memory partition. These devices have the following names:
Common memory direct access, character special device.
Attribute memory direct access, character special device.
Common memory region 0, character special device.
Common memory region 0, block special device.
Attribute memory region 0, character special device.
The block special device for a card's common memory can be used to create a filesystem on
a card, and the device can be mounted in much the same way as a floppy disk. In some
cases, you may need to explicitly specify the card's capacity when creating a filesystem.
The character special devices can be used to read and write arbitrary numbers of bytes to
arbitrary locations. For devices that need to be explicitly erased before writing, if a
write request is aligned and sized on erase block boundaries for the target memory card,
the driver will erase the target region before writing to the card.
Since any PCMCIA card can be accessed as a memory card, memory_cs can be bound to any card
regardless of function, and regardless of what other drivers might also be bound to that
card. For example, this driver can be bound to a card and then used to read out the con-
tents of the card's attribute memory.
Selects the PCMCIA debugging level. This parameter is only available if the module
is compiled with debugging enabled. A non-zero value enables debugging.
Sets the access speed of the shared memory window for direct access devices, in
nanoseconds. The default is 0 (i.e., no extra wait states). Values of up to 1000
A flag indicating if direct access devices should be configured for 8-bit (if 0) or
16-bit (if 1) transfers. The default is 1 (16-bit).
Explicitly specifies the size of a simple SRAM card, skipping the default (and
sometimes unreliable) size check.
These are defined in <pcmcia/memory.h>.
This takes an argument of type (region_info_t *), defined in <pcmcia/bulkmem.h>.
The structure will be filled in with memory region information for this device,
such as access speed, erase block size, and JEDEC identifiers.
This takes an argument of type (erase_info_t *), specifying the offset and length
of a memory region to be erased.
David Hinds - email@example.com
cardmgr(8), pcmcia(5), memory_cb(4).
pcmcia-cs 2000/06/12 21:24:48 MEMORY_CS(4)