From 0bed4b7aa02c06e05121875dc443295d55b9d91d Mon Sep 17 00:00:00 2001 From: Dirk B Date: Wed, 16 Dec 2015 08:11:41 +0100 Subject: ARM: 8484/1: Documentation: l2c2x0: Mention separate controllers explicitly The documentation in l2c2x0.txt is only valid for L2C210/L2C220/L2C310 (also known as PL210/PL220/PL310 and variants). Mention this explicitly. And add a note why this isn't valid for integrated L2 controllers. Signed-off-by: Dirk Behme Signed-off-by: Russell King diff --git a/Documentation/devicetree/bindings/arm/l2c2x0.txt b/Documentation/devicetree/bindings/arm/l2c2x0.txt index 06c88a4..1c04354 100644 --- a/Documentation/devicetree/bindings/arm/l2c2x0.txt +++ b/Documentation/devicetree/bindings/arm/l2c2x0.txt @@ -1,7 +1,8 @@ * ARM L2 Cache Controller -ARM cores often have a separate level 2 cache controller. There are various -implementations of the L2 cache controller with compatible programming models. +ARM cores often have a separate L2C210/L2C220/L2C310 (also known as PL210/PL220/ +PL310 and variants) based level 2 cache controller. All these various implementations +of the L2 cache controller have compatible programming models (Note 1). Some of the properties that are just prefixed "cache-*" are taken from section 3.7.3 of the ePAPR v1.1 specification which can be found at: https://www.power.org/wp-content/uploads/2012/06/Power_ePAPR_APPROVED_v1.1.pdf @@ -91,3 +92,9 @@ L2: cache-controller { cache-level = <2>; interrupts = <45>; }; + +Note 1: The description in this document doesn't apply to integrated L2 + cache controllers as found in e.g. Cortex-A15/A7/A57/A53. These + integrated L2 controllers are assumed to be all preconfigured by + early secure boot code. Thus no need to deal with their configuration + in the kernel at all. -- cgit v0.10.2