ARM: 8448/1: add some L220 DT settings

The RealView ARM11MPCore enables parity, eventmon and shared
override in the cache controller through its current boardfile,
but the code and DT bindings for the ARM L220 is currently
lacking the ability to set this up from DT. Add the required
bool parameters for parity and shared override, but keep
eventmon out of it: this should be enabled by the event
monitor code.

Cc: devicetree@vger.kernel.org
Acked-by: NRob Herring <robh@kernel.org>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Documentation/devicetree/bindings/arm/l2cc.txt

@@ -67,12 +67,14 @@ Optional properties:
   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 pl310 cache controller 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).
+- 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-enable : enable parity checking on the L2 cache (L220 or PL310).
+- arm,parity-disable : disable parity checking on the L2 cache (L220 or PL310).
 - prefetch-data : Data prefetch. Value: <0> (forcibly disable), <1>
   (forcibly enable), property absent (retain settings set by firmware)
 - prefetch-instr : Instruction prefetch. Value: <0> (forcibly disable),

arch/arm/mm/cache-l2x0.c

@@ -1060,6 +1060,18 @@ static void __init l2x0_of_parse(const struct device_node *np,
 		val |= (dirty - 1) << L2X0_AUX_CTRL_DIRTY_LATENCY_SHIFT;
 	}
 
+	if (of_property_read_bool(np, "arm,parity-enable")) {
+		mask &= ~L2C_AUX_CTRL_PARITY_ENABLE;
+		val |= L2C_AUX_CTRL_PARITY_ENABLE;
+	} else if (of_property_read_bool(np, "arm,parity-disable")) {
+		mask &= ~L2C_AUX_CTRL_PARITY_ENABLE;
+	}
+
+	if (of_property_read_bool(np, "arm,shared-override")) {
+		mask &= ~L2C_AUX_CTRL_SHARED_OVERRIDE;
+		val |= L2C_AUX_CTRL_SHARED_OVERRIDE;
+	}
+
 	ret = l2x0_cache_size_of_parse(np, aux_val, aux_mask, &assoc, SZ_256K);
 	if (ret)
 		return;
@@ -1176,6 +1188,14 @@ static void __init l2c310_of_parse(const struct device_node *np,
 		*aux_mask &= ~L2C_AUX_CTRL_SHARED_OVERRIDE;
 	}
 
+	if (of_property_read_bool(np, "arm,parity-enable")) {
+		*aux_val |= L2C_AUX_CTRL_PARITY_ENABLE;
+		*aux_mask &= ~L2C_AUX_CTRL_PARITY_ENABLE;
+	} else if (of_property_read_bool(np, "arm,parity-disable")) {
+		*aux_val &= ~L2C_AUX_CTRL_PARITY_ENABLE;
+		*aux_mask &= ~L2C_AUX_CTRL_PARITY_ENABLE;
+	}
+
 	prefetch = l2x0_saved_regs.prefetch_ctrl;
 
 	ret = of_property_read_u32(np, "arm,double-linefill", &val);