[PATCH] ARM: l2c: add options to overwrite prefetching behavior
From: hauke@hauke-m.de (Hauke Mehrtens)
Date: 2015-05-13 23:42:00
Also in:
linux-devicetree
Subsystem:
arm port, open firmware and flattened device tree bindings, the rest · Maintainers:
Russell King, Rob Herring, Krzysztof Kozlowski, Conor Dooley, Linus Torvalds
These options make it possible to overwrites the data and instruction prefetching behavior of the arm pl310 cache controller. Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de> --- Documentation/devicetree/bindings/arm/l2cc.txt | 4 ++++ arch/arm/mm/cache-l2x0.c | 10 ++++++++++ 2 files changed, 14 insertions(+)
diff --git a/Documentation/devicetree/bindings/arm/l2cc.txt b/Documentation/devicetree/bindings/arm/l2cc.txt
index 0dbabe9..528821a 100644
--- a/Documentation/devicetree/bindings/arm/l2cc.txt
+++ b/Documentation/devicetree/bindings/arm/l2cc.txt@@ -67,6 +67,10 @@ Optional properties: disable if zero. - arm,prefetch-offset : Override prefetch offset value. Valid values are 0-7, 15, 23, and 31. +- arm,prefetch-data : Enable data prefetch. Enabling prefetching + can improve performance. +- arm,prefetch-instr : Enable instruction prefetch. Enabling prefetching + can improve performance. Example:
diff --git a/arch/arm/mm/cache-l2x0.c b/arch/arm/mm/cache-l2x0.c
index e309c8f..f919548 100644
--- a/arch/arm/mm/cache-l2x0.c
+++ b/arch/arm/mm/cache-l2x0.c@@ -1149,6 +1149,16 @@ static void __init l2c310_of_parse(const struct device_node *np, } } + if (of_property_read_bool(np, "arm,prefetch-data")) { + *aux_val |= L310_AUX_CTRL_DATA_PREFETCH; + *aux_mask &= ~L310_AUX_CTRL_DATA_PREFETCH; + } + + if (of_property_read_bool(np, "arm,prefetch-instr")) { + *aux_val |= L310_AUX_CTRL_INSTR_PREFETCH; + *aux_mask &= ~L310_AUX_CTRL_INSTR_PREFETCH; + } + prefetch = l2x0_saved_regs.prefetch_ctrl; ret = of_property_read_u32(np, "arm,double-linefill", &val);
--
2.1.4