[PATCH 4/4 v2] mtd/powerpc: Describe multiple "reg" tuples usage

[PATCH 4/4 v2] mtd/powerpc: Describe multiple "reg" tuples usage

[Stefan Roese]

Signed-off-by: Stefan Roese <sr@denx.de>
CC: Grant Likely <grant.likely@secretlab.ca>
---
 Documentation/powerpc/dts-bindings/mtd-physmap.txt |   20 +++++++++++++++++++-
 1 files changed, 19 insertions(+), 1 deletions(-)

diff --git a/Documentation/powerpc/dts-bindings/mtd-physmap.txt b/Documentation/powerpc/dts-bindings/mtd-physmap.txt
index ab1115e..a3fa9e0 100644
--- a/Documentation/powerpc/dts-bindings/mtd-physmap.txt
+++ b/Documentation/powerpc/dts-bindings/mtd-physmap.txt
@@ -5,7 +5,10 @@ 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 of the flash chip
+ - reg : Address range(s) of the flash chip(s)
+   It's possible to (optionally) define multiple "reg" tuples so that the
+   Intel P30 48F4400 chip which consists internally of 2 non-identical
+   NOR chips on one die can also be supported.
  - bank-width : Width (in bytes) of the flash bank.  Equal to the
    device width times the number of interleaved chips.
  - #address-cells, #size-cells : Must be present if the flash has
@@ -58,3 +61,18 @@ Example:
 			read-only;
 		};
 	};
+
+Here an example with multiple "reg" tuples (e.g. Intel P30):
+
+	flash@f0000000,0 {
+		#address-cells = <1>;
+		#size-cells = <1>;
+		compatible = "cfi-flash";
+		reg = <0 0x00000000 0x02000000
+		       0 0x02000000 0x02000000>;
+		bank-width = <2>;
+		partition@0 {
+			label = "test-part1";
+			reg = <0 0x04000000>;
+		};
+	};
-- 
1.6.2.2

Re: [PATCH 4/4 v2] mtd/powerpc: Describe multiple "reg" tuples usage

[Grant Likely]

On Tue, Apr 7, 2009 at 2:39 AM, Stefan Roese <sr@denx.de> wrote:
> Signed-off-by: Stefan Roese <sr@denx.de>
> CC: Grant Likely <grant.likely@secretlab.ca>
> ---
> =A0Documentation/powerpc/dts-bindings/mtd-physmap.txt | =A0 20 ++++++++++=
+++++++++-
> =A01 files changed, 19 insertions(+), 1 deletions(-)
>
> diff --git a/Documentation/powerpc/dts-bindings/mtd-physmap.txt b/Documen=
tation/powerpc/dts-bindings/mtd-physmap.txt
> index ab1115e..a3fa9e0 100644
> --- a/Documentation/powerpc/dts-bindings/mtd-physmap.txt
> +++ b/Documentation/powerpc/dts-bindings/mtd-physmap.txt
> @@ -5,7 +5,10 @@ file systems on embedded devices.
>
> =A0- compatible : should contain the specific model of flash chip(s)
> =A0 =A0used, if known, followed by either "cfi-flash" or "jedec-flash"
> - - reg : Address range of the flash chip
> + - reg : Address range(s) of the flash chip(s)
> + =A0 It's possible to (optionally) define multiple "reg" tuples so that =
the
> + =A0 Intel P30 48F4400 chip which consists internally of 2 non-identical
> + =A0 NOR chips on one die can also be supported.

This isn't a P30 48F4400 specific feature, even if it is the only
current user.  This description works for any arrangement of multiple
NOR chips.  I isn't really appropriate to mention the P30 in this way
and it should be more generic.

> =A0- bank-width : Width (in bytes) of the flash bank. =A0Equal to the
> =A0 =A0device width times the number of interleaved chips.
> =A0- #address-cells, #size-cells : Must be present if the flash has
> @@ -58,3 +61,18 @@ Example:
> =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0read-only;
> =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0};
> =A0 =A0 =A0 =A0};
> +
> +Here an example with multiple "reg" tuples (e.g. Intel P30):

However, it is completely appropriate to mention P30 here because it
is in the context of an example.

> +
> + =A0 =A0 =A0 flash@f0000000,0 {
> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 #address-cells =3D <1>;
> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 #size-cells =3D <1>;
> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 compatible =3D "cfi-flash";

For best practice, compatible should also specify the exact chip in this ca=
se.

g.

--=20
Grant Likely, B.Sc., P.Eng.
Secret Lab Technologies Ltd.