[PATCH 10/21] ARM: MM: Add DT binding for Feroceon L2 cache
From: Jason Cooper <hidden>
Date: 2014-02-07 01:27:52
On Fri, Feb 07, 2014 at 12:42:06AM +0100, Andrew Lunn wrote:
Instantiate the L2 cache from DT. Indicate in DT where the cache control register is and if write through should be made. Signed-off-by: Andrew Lunn <andrew@lunn.ch> --- .../devicetree/bindings/arm/mrvl/foroceon.txt | 19 +++++++++ arch/arm/boot/dts/kirkwood.dtsi | 5 +++ arch/arm/include/asm/hardware/cache-feroceon-l2.h | 2 + arch/arm/mach-kirkwood/board-dt.c | 15 +------ arch/arm/mm/cache-feroceon-l2.c | 46 ++++++++++++++++++++++ 5 files changed, 73 insertions(+), 14 deletions(-) create mode 100644 Documentation/devicetree/bindings/arm/mrvl/foroceon.txt
for the next revision, please split out the dtsi changes into a separate patch.
quoted hunk ↗ jump to hunk
diff --git a/Documentation/devicetree/bindings/arm/mrvl/foroceon.txt b/Documentation/devicetree/bindings/arm/mrvl/foroceon.txt new file mode 100644 index 000000000000..8058676d1476 --- /dev/null +++ b/Documentation/devicetree/bindings/arm/mrvl/foroceon.txt
name typo.
quoted hunk ↗ jump to hunk
@@ -0,0 +1,19 @@ +* Marvell Feroceon Cache + +Required properties: +- compatible : Should be "marvell,feroceon-kirkwood".
This is a little ambiguous, I'd like to see 'l2' in the compatible string.
+- reg : Address of the L2 cache control register
+
+Optional properties:
+- writethrough : only if present, the cache will be used in write through mode.
+
+Example:
+ l2: l2-cache at 20128 {
+ compatible = "marvell,marvell,feroceon-kirkwood";only need a single 'marvell'.
quoted hunk ↗ jump to hunk
+ reg = <0x20128 0x4>; + }; + +There are at least two variants of the Feroceon, differing in how +write through is enabled or not. If mv78xx0 support is added, it is +expected to have a different compatibility string. +diff --git a/arch/arm/boot/dts/kirkwood.dtsi b/arch/arm/boot/dts/kirkwood.dtsi index 6abf44d257df..1d8129ac2672 100644 --- a/arch/arm/boot/dts/kirkwood.dtsi +++ b/arch/arm/boot/dts/kirkwood.dtsi@@ -161,6 +161,11 @@ #clock-cells = <1>; }; + l2: l2-cache at 20128 { + compatible = "marvell,feroceon-kirkwood"; + reg = <0x20128 0x4>; + }; + intc: main-interrupt-ctrl at 20200 { compatible = "marvell,orion-intc"; interrupt-controller;diff --git a/arch/arm/include/asm/hardware/cache-feroceon-l2.h b/arch/arm/include/asm/hardware/cache-feroceon-l2.h index 8edd330aabf6..12e1588dc4f1 100644 --- a/arch/arm/include/asm/hardware/cache-feroceon-l2.h +++ b/arch/arm/include/asm/hardware/cache-feroceon-l2.h@@ -9,3 +9,5 @@ */ extern void __init feroceon_l2_init(int l2_wt_override); +extern int __init feroceon_of_init(void); +diff --git a/arch/arm/mach-kirkwood/board-dt.c b/arch/arm/mach-kirkwood/board-dt.c index 34c35510fd17..2ef59ee2182d 100644 --- a/arch/arm/mach-kirkwood/board-dt.c +++ b/arch/arm/mach-kirkwood/board-dt.c@@ -42,19 +42,6 @@ static void __init kirkwood_map_io(void) iotable_init(kirkwood_io_desc, ARRAY_SIZE(kirkwood_io_desc)); } -static void __init kirkwood_l2_init(void) -{ -#ifdef CONFIG_CACHE_FEROCEON_L2 -#ifdef CONFIG_CACHE_FEROCEON_L2_WRITETHROUGH - writel(readl(L2_CONFIG_REG) | L2_WRITETHROUGH, L2_CONFIG_REG); - feroceon_l2_init(1); -#else - writel(readl(L2_CONFIG_REG) & ~L2_WRITETHROUGH, L2_CONFIG_REG); - feroceon_l2_init(0); -#endif -#endif -} - static struct resource kirkwood_cpufreq_resources[] = { [0] = { .start = CPU_CONTROL_PHYS,@@ -211,7 +198,7 @@ static void __init kirkwood_dt_init(void) BUG_ON(mvebu_mbus_dt_init()); - kirkwood_l2_init(); + feroceon_of_init(); kirkwood_cpufreq_init(); kirkwood_cpuidle_init();diff --git a/arch/arm/mm/cache-feroceon-l2.c b/arch/arm/mm/cache-feroceon-l2.c index 898362e7972b..193fe7dbdb12 100644 --- a/arch/arm/mm/cache-feroceon-l2.c +++ b/arch/arm/mm/cache-feroceon-l2.c@@ -13,11 +13,17 @@ */ #include <linux/init.h> +#include <linux/of.h> +#include <linux/of_address.h> #include <linux/highmem.h> +#include <linux/io.h> #include <asm/cacheflush.h> #include <asm/cp15.h> #include <asm/hardware/cache-feroceon-l2.h> +#define L2_WRITETHROUGH_KIRKWOOD 0x00000010 + + /* * Low-level cache maintenance operations. *@@ -350,3 +356,43 @@ void __init feroceon_l2_init(int __l2_wt_override) printk(KERN_INFO "Feroceon L2: Cache support initialised%s.\n", l2_wt_override ? ", in WT override mode" : ""); } +#ifdef CONFIG_OF +static const struct of_device_id feroceon_ids[] __initconst = { + { .compatible = "marvell,feroceon-kirkwood"}, + {} +}; + +int __init feroceon_of_init(void) +{ + struct device_node *node; + void __iomem *base; + bool writethrough = false; + struct resource res; + + node = of_find_matching_node(NULL, feroceon_ids); + if (!node) { + pr_info("Didn't find marvell,feroceon-*, not enabling it\n"); + return -ENODEV; + }
I'd prefer to fallback to hardcoded register address here. We know we're on kirkwood at this point. thx, Jason.
+
+ if (of_property_read_bool(node, "writethrough"))
+ writethrough = true;
+
+ if (of_address_to_resource(node, 0, &res))
+ return -ENODEV;
+
+ base = ioremap(res.start, resource_size(&res));
+ if (!base)
+ return -ENOMEM;
+
+ if (writethrough) {
+ writel(readl(base) | L2_WRITETHROUGH_KIRKWOOD, base);
+ feroceon_l2_init(1);
+ } else {
+ writel(readl(base) & ~L2_WRITETHROUGH_KIRKWOOD, base);
+ feroceon_l2_init(0);
+ }
+
+ return 0;
+}
+#endif
--
1.8.5.3