Linux commit 8ecd7f5970c5 ("ARM: 8483/1: Documentation: l2c: Rename
l2cc to l2c2x0")
Linux docs:
Documentation/devicetree/bindings/arm/l2c2x0.txt
Copied from Linux kernel v5.0.
"The documentation in the l2cc.txt is specific to the L2 cache
controllers L2C210/L2C220/L2C310 (also known as PL210/PL220/PL310
and variants) and not generic as the file name implies. It's not
valid for integrated L2 controllers as found in e.g.
Cortex-A15/A7/A57/A53."
Reviewed-by: Simon Glass
Signed-off-by: Dinh Nguyen
---
.../devicetree/bindings/arm/l2c2x0.txt| 114 ++
1 file changed, 114 insertions(+)
create mode 100644 Documentation/devicetree/bindings/arm/l2c2x0.txt
diff --git a/Documentation/devicetree/bindings/arm/l2c2x0.txt
b/Documentation/devicetree/bindings/arm/l2c2x0.txt
new file mode 100644
index 00..fbe6cb21f4
--- /dev/null
+++ b/Documentation/devicetree/bindings/arm/l2c2x0.txt
@@ -0,0 +1,114 @@
+* ARM L2 Cache Controller
+
+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 Devicetree Specification which can be found at:
+https://www.devicetree.org/specifications/
+
+The ARM L2 cache representation in the device tree should be done as follows:
+
+Required properties:
+
+- compatible : should be one of:
+ "arm,pl310-cache"
+ "arm,l220-cache"
+ "arm,l210-cache"
+ "bcm,bcm11351-a2-pl310-cache": DEPRECATED by "brcm,bcm11351-a2-pl310-cache"
+ "brcm,bcm11351-a2-pl310-cache": For Broadcom bcm11351 chipset where an
+ offset needs to be added to the address before passing down to the L2
+ cache controller
+ "marvell,aurora-system-cache": Marvell Controller designed to be
+ compatible with the ARM one, with system cache mode (meaning
+ maintenance operations on L1 are broadcasted to the L2 and L2
+ performs the same operation).
+ "marvell,aurora-outer-cache": Marvell Controller designed to be
+ compatible with the ARM one with outer cache mode.
+ "marvell,tauros3-cache": Marvell Tauros3 cache controller, compatible
+ with arm,pl310-cache controller.
+- cache-unified : Specifies the cache is a unified cache.
+- cache-level : Should be set to 2 for a level 2 cache.
+- reg : Physical base address and size of cache controller's memory mapped
+ registers.
+
+Optional properties:
+
+- arm,data-latency : Cycles of latency for Data RAM accesses. Specifies 3
cells of
+ read, write and setup latencies. Minimum valid values are 1. Controllers
+ without setup latency control should use a value of 0.
+- arm,tag-latency : Cycles of latency for Tag RAM accesses. Specifies 3 cells
of
+ read, write and setup latencies. Controllers without setup latency control
+ should use 0. Controllers without separate read and write Tag RAM latency
+ values should only use the first cell.
+- arm,dirty-latency : Cycles of latency for Dirty RAMs. This is a single cell.
+- arm,filter-ranges : Starting address and length of window to
+ filter. Addresses in the filter window are directed to the M1 port. Other
+ addresses will go to the M0 port.
+- arm,io-coherent : indicates that the system is operating in an hardware
+ I/O coherent mode. Valid only when the arm,pl310-cache compatible
+ string is used.
+- interrupts : 1 combined interrupt.
+- cache-size : specifies the size in bytes of the cache
+- cache-sets : specifies the number of associativity sets of the cache
+- cache-block-size : specifies the size in bytes of a cache block
+- cache-line-size : specifies the size in bytes of a line in the cache,
+ if this is not specified, the line size is assumed to be equal to the
+ cache block size
+- cache-id-part: cache id part number to be used if it is not present
+ on hardware
+- wt-override: If present then L2 is forced to Write through mode
+- arm,double-linefill : Override double linefill enable setting. Enable if
+ non-zero, disable if zero.
+- arm,double-linefill-incr : Override double linefill on INCR read. Enable
+ if non-zero, disable if zero.
+- arm,double-linefill-wrap : Override double linefill on WRAP read. Enable
+ if non-zero, disable if zero.
+- arm,prefetch-drop : Override prefetch drop enable setting. Enable if
non-zero,
+ disable if zero.
+- arm,prefetch-offset : Override prefetch offset value. Valid values are
+ 0-7, 15, 23, and 31.
+- arm,shared-override : The default behavior of the L220 or PL310 cache
+ controllers with respect to the shareable attribute is to transform "normal
+ memory non-cacheable transactions" into "cacheable no allocate" (for reads)
+ or "write through no write allocate" (for writes).
+ On systems where this may cause DMA buffer corruption, this property must be
+ specified to indicate that such transforms are precluded.
+- arm,parity-en
