[PATCH] [POWERPC] Add docs for Freescale PowerQUICC SATA device tree nodes

[PATCH] [POWERPC] Add docs for Freescale PowerQUICC SATA device tree nodes

[Kumar Gala]

Signed-off-by: Li Yang <leoli@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
---
 Documentation/powerpc/booting-without-of.txt |   30 ++++++++++++++++++++++++++
 1 files changed, 30 insertions(+), 0 deletions(-)

diff --git a/Documentation/powerpc/booting-without-of.txt b/Documentation/powerpc/booting-without-of.txt
index 3584c33..387310a 100644
--- a/Documentation/powerpc/booting-without-of.txt
+++ b/Documentation/powerpc/booting-without-of.txt
@@ -2743,6 +2743,36 @@ platforms are moved over to use the flattened-device-tree model.
 		};
 	};

+    * Freescale 8xxx/3.0 Gb/s SATA nodes
+
+    SATA nodes are defined to describe on-chip Serial ATA controllers.
+    Each SATA port should have its own node.
+
+    Required properties:
+    - compatible        : compatible list, contains 2 entries, first is
+			 "fsl,CHIP-sata", where CHIP is the processor
+			 (mpc8315, mpc8379, etc.) and the second is
+			 "fsl,pq-sata"
+    - interrupts        : <interrupt mapping for SATA IRQ>
+    - cell-index        : controller index.
+                              1 for controller @ 0x18000
+                              2 for controller @ 0x19000
+                              3 for controller @ 0x1a000
+                              4 for controller @ 0x1b000
+
+    Optional properties:
+    - interrupt-parent  : optional, if needed for interrupt mapping
+    - reg               : <registers mapping>
+
+   Example:
+
+	sata@18000 {
+		compatible = "fsl,mpc8379-sata", "fsl,pq-sata";
+		reg = <0x18000 0x1000>;
+		cell-index = <1>;
+		interrupts = <2c 8>;
+		interrupt-parent = < &ipic >;
+        };

    More devices will be defined as this spec matures.

-- 
1.5.3.7

Re: [PATCH] [POWERPC] Add docs for Freescale PowerQUICC SATA device tree nodes

[Grant Likely]

On 1/22/08, Kumar Gala <galak@kernel.crashing.org> wrote:
> Signed-off-by: Li Yang <leoli@freescale.com>
> Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
> ---
>  Documentation/powerpc/booting-without-of.txt |   30 ++++++++++++++++++++++++++
>  1 files changed, 30 insertions(+), 0 deletions(-)
>
> diff --git a/Documentation/powerpc/booting-without-of.txt b/Documentation/powerpc/booting-without-of.txt
> index 3584c33..387310a 100644
> --- a/Documentation/powerpc/booting-without-of.txt
> +++ b/Documentation/powerpc/booting-without-of.txt
> @@ -2743,6 +2743,36 @@ platforms are moved over to use the flattened-device-tree model.
>                 };
>         };
>
> +    * Freescale 8xxx/3.0 Gb/s SATA nodes
> +
> +    SATA nodes are defined to describe on-chip Serial ATA controllers.
> +    Each SATA port should have its own node.
> +
> +    Required properties:
> +    - compatible        : compatible list, contains 2 entries, first is
> +                        "fsl,CHIP-sata", where CHIP is the processor
> +                        (mpc8315, mpc8379, etc.) and the second is
> +                        "fsl,pq-sata"

As discussed on IRC, I don't like the approach of trying to define
generic names for these ip cores.  Too much can change in the future
to make the definition of the generic type drift over time.  Better to
always refer to exact chip variants.

ie.  Assuming mpc8315 was the first part to contain the sata core; the
dts should claim "fsl,CHIP-sata","fsl,mpc8315-sata" instead of
"fsl,CHIP-sata","fsl,pq-sata".

It ends up being the same amount of work to support, but it doesn't
fall into the trap of making stuff up.

Another example; when describing serial ports, we still use an
*ancient* device to claim compatibility with: "ns16550".  ns16550 is
specific, not generic, yet everyone still knows what it means.

Cheers,
g.

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

Re: [PATCH] [POWERPC] Add docs for Freescale PowerQUICC SATA device tree nodes

[Kumar Gala]

On Jan 22, 2008, at 3:54 PM, Grant Likely wrote:

> On 1/22/08, Kumar Gala <galak@kernel.crashing.org> wrote:
>> Signed-off-by: Li Yang <leoli@freescale.com>
>> Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
>> ---
>> Documentation/powerpc/booting-without-of.txt |   30 ++++++++++++++++ 
>> ++++++++++
>> 1 files changed, 30 insertions(+), 0 deletions(-)
>>
>> diff --git a/Documentation/powerpc/booting-without-of.txt b/ 
>> Documentation/powerpc/booting-without-of.txt
>> index 3584c33..387310a 100644
>> --- a/Documentation/powerpc/booting-without-of.txt
>> +++ b/Documentation/powerpc/booting-without-of.txt
>> @@ -2743,6 +2743,36 @@ platforms are moved over to use the  
>> flattened-device-tree model.
>>                };
>>        };
>>
>> +    * Freescale 8xxx/3.0 Gb/s SATA nodes
>> +
>> +    SATA nodes are defined to describe on-chip Serial ATA  
>> controllers.
>> +    Each SATA port should have its own node.
>> +
>> +    Required properties:
>> +    - compatible        : compatible list, contains 2 entries,  
>> first is
>> +                        "fsl,CHIP-sata", where CHIP is the processor
>> +                        (mpc8315, mpc8379, etc.) and the second is
>> +                        "fsl,pq-sata"
>
> As discussed on IRC, I don't like the approach of trying to define
> generic names for these ip cores.  Too much can change in the future
> to make the definition of the generic type drift over time.  Better to
> always refer to exact chip variants.
>
> ie.  Assuming mpc8315 was the first part to contain the sata core; the
> dts should claim "fsl,CHIP-sata","fsl,mpc8315-sata" instead of
> "fsl,CHIP-sata","fsl,pq-sata".
>
> It ends up being the same amount of work to support, but it doesn't
> fall into the trap of making stuff up.
>
> Another example; when describing serial ports, we still use an
> *ancient* device to claim compatibility with: "ns16550".  ns16550 is
> specific, not generic, yet everyone still knows what it means.

Think of the 'specific' name as 'fsl,pq-sata'.  Just like ns16550  
there are lot of variants that do slightly different things which is  
captured by the even more specific 'fsl,mpc8313-sata' name.

I note your disagreement. :)

- k