Cc: Vitaly Wool <redacted>
Cc: Artem Bityutskiy <redacted>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Ken MacLeod <redacted>
Cc: Albrecht Dreß <redacted>
---
 Documentation/powerpc/dts-bindings/mtd-physmap.txt |   42 ++++++++++++-------
 drivers/mtd/maps/physmap_of.c                      |    4 ++
 2 files changed, 30 insertions(+), 16 deletions(-)

diff --git a/Documentation/powerpc/dts-bindings/mtd-physmap.txt b/Documentation/powerpc/dts-bindings/mtd-physmap.txt
index 667c9bd..80152cb 100644
--- a/Documentation/powerpc/dts-bindings/mtd-physmap.txt
+++ b/Documentation/powerpc/dts-bindings/mtd-physmap.txt

@@ -1,18 +1,19 @@
-CFI or JEDEC memory-mapped NOR flash
+CFI or JEDEC memory-mapped NOR flash, MTD-RAM (NVRAM...)

 Flash chips (Memory Technology Devices) are often used for solid state
 file systems on embedded devices.

- - compatible : should contain the specific model of flash chip(s)
-   used, if known, followed by either "cfi-flash" or "jedec-flash"
- - reg : Address range(s) of the flash chip(s)
+ - compatible : should contain the specific model of mtd chip(s)
+   used, if known, followed by either "cfi-flash", "jedec-flash"
+   or "mtd-ram".
+ - reg : Address range(s) of the mtd chip(s)
   It's possible to (optionally) define multiple "reg" tuples so that
-   non-identical NOR chips can be described in one flash node.
- - bank-width : Width (in bytes) of the flash bank.  Equal to the
+   non-identical chips can be described in one node.
+ - bank-width : Width (in bytes) of the bank.  Equal to the
   device width times the number of interleaved chips.
- - device-width : (optional) Width of a single flash chip.  If
+ - device-width : (optional) Width of a single mtd chip.  If
   omitted, assumed to be equal to 'bank-width'.
- - #address-cells, #size-cells : Must be present if the flash has
+ - #address-cells, #size-cells : Must be present if the device has
   sub-nodes representing partitions (see below).  In this case
   both #address-cells and #size-cells must be equal to 1.

@@ -22,24 +23,24 @@ are defined:

 - vendor-id : Contains the flash chip's vendor id (1 byte).
 - device-id : Contains the flash chip's device id (1 byte).

-In addition to the information on the flash bank itself, the
+In addition to the information on the mtd bank itself, the
 device tree may optionally contain additional information
-describing partitions of the flash address space.  This can be
+describing partitions of the address space.  This can be
 used on platforms which have strong conventions about which
-portions of the flash are used for what purposes, but which don't
+portions of a flash are used for what purposes, but which don't
 use an on-flash partition table such as RedBoot.

-Each partition is represented as a sub-node of the flash device.
+Each partition is represented as a sub-node of the mtd device.
 Each node's name represents the name of the corresponding
-partition of the flash device.
+partition of the mtd device.

 Flash partitions
- - reg : The partition's offset and size within the flash bank.
- - label : (optional) The label / name for this flash partition.
+ - reg : The partition's offset and size within the mtd bank.
+ - label : (optional) The label / name for this partition.
   If omitted, the label is taken from the node name (excluding
   the unit address).
 - read-only : (optional) This parameter, if present, is a hint to
-   Linux that this flash partition should only be mounted
+   Linux that this partition should only be mounted
   read-only.  This is usually used for flash partitions
   containing early-boot firmware images or data which should not
   be clobbered.

@@ -78,3 +79,12 @@ Here an example with multiple "reg" tuples:

                       reg = <0 0x04000000>;
               };
       };
+
+An example using SRAM:
+
+       sram@2,0 {
+               compatible = "samsung,k6f1616u6a", "mtd-ram";
+               reg = <2 0 0x00200000>;
+               bank-width = <2>;
+       };
+

diff --git a/drivers/mtd/maps/physmap_of.c b/drivers/mtd/maps/physmap_of.c
index 39d357b..45eee20 100644
--- a/drivers/mtd/maps/physmap_of.c
+++ b/drivers/mtd/maps/physmap_of.c

@@ -360,6 +360,10 @@ static struct of_device_id of_flash_match[] = {

               .data           = (void *)"jedec_probe",
       },
       {
+               .compatible     = "mtd-ram",
+               .data           = (void *)"map_ram",
+       },
+       {
               .type           = "rom",
               .compatible     = "direct-mapped"
       },
--
1.6.3.1

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