[PATCH 74/75] ARM: l2c: always enable low power modes

[Russell King]

Always enable the L2C low power modes on L2C-310 R3P0 and newer parts.

Signed-off-by: Russell King <rmk+kernel at arm.linux.org.uk>
---
 Documentation/devicetree/bindings/arm/l2cc.txt |  2 --
 arch/arm/mm/cache-l2x0.c                       | 22 ++++++++++++----------
 2 files changed, 12 insertions(+), 12 deletions(-)

diff --git a/Documentation/devicetree/bindings/arm/l2cc.txt b/Documentation/devicetree/bindings/arm/l2cc.txt
index e0dd400ecea6..b513cb8196fe 100644
--- a/Documentation/devicetree/bindings/arm/l2cc.txt
+++ b/Documentation/devicetree/bindings/arm/l2cc.txt
@@ -40,8 +40,6 @@ implementations of the L2 cache controller with compatible programming models.
 - arm,filter-ranges : <start length> 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,dynamic-clk-gating : Enables dynamic clock gating (PL310)
-- arm,standby-mode : Enables standby mode (PL310)
 - interrupts : 1 combined interrupt.
 - cache-id-part: cache id part number to be used if it is not present
   on hardware
diff --git a/arch/arm/mm/cache-l2x0.c b/arch/arm/mm/cache-l2x0.c
index 700a66260f94..b1f103d402be 100644
--- a/arch/arm/mm/cache-l2x0.c
+++ b/arch/arm/mm/cache-l2x0.c
@@ -752,6 +752,18 @@ static void __init l2c310_enable(void __iomem *base, u32 aux, unsigned num_lock)
 			1 + (prefetch & L310_PREFETCH_CTRL_OFFSET_MASK));
 	}
 
+	/* r3p0 or later has power control register */
+	if (rev >= L310_CACHE_ID_RTL_R3P0) {
+		u32 power_ctrl;
+
+		l2c_write_sec(L310_DYNAMIC_CLK_GATING_EN | L310_STNDBY_MODE_EN,
+			      base, L310_POWER_CTRL);
+		power_ctrl = readl_relaxed(base + L310_POWER_CTRL);
+		pr_info("L2C-310: dynamic clock gating %sabled, standby mode %sabled\n",
+			power_ctrl & L310_DYNAMIC_CLK_GATING_EN ? "en" : "dis",
+			power_ctrl & L310_STNDBY_MODE_EN ? "en" : "dis");
+	}
+
 	l2c_enable(base, aux, num_lock);
 
 	if (aux & L310_AUX_CTRL_FULL_LINE_ZERO) {
@@ -1033,7 +1045,6 @@ static void __init l2c310_of_parse(const struct device_node *np,
 	u32 data[3] = { 0, 0, 0 };
 	u32 tag[3] = { 0, 0, 0 };
 	u32 filter[2] = { 0, 0 };
-	u32 val;
 
 	of_property_read_u32_array(np, "arm,tag-latency", tag, ARRAY_SIZE(tag));
 	if (tag[0] && tag[1] && tag[2])
@@ -1060,15 +1071,6 @@ static void __init l2c310_of_parse(const struct device_node *np,
 		writel_relaxed((filter[0] & ~(SZ_1M - 1)) | L310_ADDR_FILTER_EN,
 			       l2x0_base + L310_ADDR_FILTER_START);
 	}
-
-	val = 0;
-	if (of_property_read_bool(np, "arm,dynamic-clk-gating"))
-		val |= L310_DYNAMIC_CLK_GATING_EN;
-	if (of_property_read_bool(np, "arm,standby-mode"))
-		val |= L310_STNDBY_MODE_EN;
-
-	if (val)
-		l2c_write_sec(val, l2x0_base, L310_POWER_CTRL);
 }
 
 static const struct l2c_init_data of_l2c310_data __initconst = {
-- 
1.8.3.1