]> git.karo-electronics.de Git - karo-tx-linux.git/commitdiff
ARM: 7009/1: l2x0: Add OF based initialization
authorRob Herring <rob.herring@calxeda.com>
Wed, 3 Aug 2011 17:12:05 +0000 (18:12 +0100)
committerRussell King <rmk+kernel@arm.linux.org.uk>
Thu, 8 Sep 2011 09:12:40 +0000 (10:12 +0100)
This adds probing for ARM L2x0 cache controllers via device tree. Support
includes the L210, L220, and PL310 controllers. The binding allows setting
up cache RAM latencies and filter addresses (PL310 only).

Signed-off-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Olof Johansson <olof@lixom.net>
Acked-by: Barry Song <21cnbao@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Documentation/devicetree/bindings/arm/l2cc.txt [new file with mode: 0644]
arch/arm/include/asm/hardware/cache-l2x0.h
arch/arm/mm/cache-l2x0.c

diff --git a/Documentation/devicetree/bindings/arm/l2cc.txt b/Documentation/devicetree/bindings/arm/l2cc.txt
new file mode 100644 (file)
index 0000000..f50e021
--- /dev/null
@@ -0,0 +1,42 @@
+* ARM L2 Cache Controller
+
+ARM cores often have a separate level 2 cache controller. There are various
+implementations of the L2 cache controller with compatible programming models.
+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"
+- 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 : <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.
+
+Example:
+
+L2: cache-controller {
+        compatible = "arm,pl310-cache";
+        reg = <0xfff12000 0x1000>;
+        arm,data-latency = <1 1 1>;
+        arm,tag-latency = <2 2 2>;
+        arm,filter-latency = <0x80000000 0x8000000>;
+        cache-unified;
+        cache-level = <2>;
+};
index bfa706ffd9683966dec63406c35e2e71942bd294..4a6004a86a12c6728c46c8da5120d329e8bb39c0 100644 (file)
@@ -47,6 +47,8 @@
 #define L2X0_CLEAN_INV_WAY             0x7FC
 #define L2X0_LOCKDOWN_WAY_D            0x900
 #define L2X0_LOCKDOWN_WAY_I            0x904
+#define L2X0_ADDR_FILTER_START         0xC00
+#define L2X0_ADDR_FILTER_END           0xC04
 #define L2X0_TEST_OPERATION            0xF00
 #define L2X0_LINE_DATA                 0xF10
 #define L2X0_LINE_TAG                  0xF30
 #define L2X0_CACHE_ID_PART_L310                (3 << 6)
 
 #define L2X0_AUX_CTRL_MASK                     0xc0000fff
+#define L2X0_AUX_CTRL_DATA_RD_LATENCY_SHIFT    0
+#define L2X0_AUX_CTRL_DATA_RD_LATENCY_MASK     0x7
+#define L2X0_AUX_CTRL_DATA_WR_LATENCY_SHIFT    3
+#define L2X0_AUX_CTRL_DATA_WR_LATENCY_MASK     (0x7 << 3)
+#define L2X0_AUX_CTRL_TAG_LATENCY_SHIFT                6
+#define L2X0_AUX_CTRL_TAG_LATENCY_MASK         (0x7 << 6)
+#define L2X0_AUX_CTRL_DIRTY_LATENCY_SHIFT      9
+#define L2X0_AUX_CTRL_DIRTY_LATENCY_MASK       (0x7 << 9)
 #define L2X0_AUX_CTRL_ASSOCIATIVITY_SHIFT      16
 #define L2X0_AUX_CTRL_WAY_SIZE_SHIFT           17
 #define L2X0_AUX_CTRL_WAY_SIZE_MASK            (0x7 << 17)
 #define L2X0_AUX_CTRL_INSTR_PREFETCH_SHIFT     29
 #define L2X0_AUX_CTRL_EARLY_BRESP_SHIFT                30
 
+#define L2X0_LATENCY_CTRL_SETUP_SHIFT  0
+#define L2X0_LATENCY_CTRL_RD_SHIFT     4
+#define L2X0_LATENCY_CTRL_WR_SHIFT     8
+
+#define L2X0_ADDR_FILTER_EN            1
+
 #ifndef __ASSEMBLY__
 extern void __init l2x0_init(void __iomem *base, __u32 aux_val, __u32 aux_mask);
+extern int l2x0_of_init(__u32 aux_val, __u32 aux_mask);
 #endif
 
 #endif
index 44c086710d2ba5d21a40741290ef8c40de35928c..c035b9aad55c29b42e9c7943444befa1fbd035e2 100644 (file)
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
+#include <linux/err.h>
 #include <linux/init.h>
 #include <linux/spinlock.h>
 #include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
 
 #include <asm/cacheflush.h>
 #include <asm/hardware/cache-l2x0.h>
@@ -351,3 +354,103 @@ void __init l2x0_init(void __iomem *base, __u32 aux_val, __u32 aux_mask)
        printk(KERN_INFO "l2x0: %d ways, CACHE_ID 0x%08x, AUX_CTRL 0x%08x, Cache size: %d B\n",
                        ways, cache_id, aux, l2x0_size);
 }
+
+#ifdef CONFIG_OF
+static void __init l2x0_of_setup(const struct device_node *np,
+                                __u32 *aux_val, __u32 *aux_mask)
+{
+       u32 data[2] = { 0, 0 };
+       u32 tag = 0;
+       u32 dirty = 0;
+       u32 val = 0, mask = 0;
+
+       of_property_read_u32(np, "arm,tag-latency", &tag);
+       if (tag) {
+               mask |= L2X0_AUX_CTRL_TAG_LATENCY_MASK;
+               val |= (tag - 1) << L2X0_AUX_CTRL_TAG_LATENCY_SHIFT;
+       }
+
+       of_property_read_u32_array(np, "arm,data-latency",
+                                  data, ARRAY_SIZE(data));
+       if (data[0] && data[1]) {
+               mask |= L2X0_AUX_CTRL_DATA_RD_LATENCY_MASK |
+                       L2X0_AUX_CTRL_DATA_WR_LATENCY_MASK;
+               val |= ((data[0] - 1) << L2X0_AUX_CTRL_DATA_RD_LATENCY_SHIFT) |
+                      ((data[1] - 1) << L2X0_AUX_CTRL_DATA_WR_LATENCY_SHIFT);
+       }
+
+       of_property_read_u32(np, "arm,dirty-latency", &dirty);
+       if (dirty) {
+               mask |= L2X0_AUX_CTRL_DIRTY_LATENCY_MASK;
+               val |= (dirty - 1) << L2X0_AUX_CTRL_DIRTY_LATENCY_SHIFT;
+       }
+
+       *aux_val &= ~mask;
+       *aux_val |= val;
+       *aux_mask &= ~mask;
+}
+
+static void __init pl310_of_setup(const struct device_node *np,
+                                 __u32 *aux_val, __u32 *aux_mask)
+{
+       u32 data[3] = { 0, 0, 0 };
+       u32 tag[3] = { 0, 0, 0 };
+       u32 filter[2] = { 0, 0 };
+
+       of_property_read_u32_array(np, "arm,tag-latency", tag, ARRAY_SIZE(tag));
+       if (tag[0] && tag[1] && tag[2])
+               writel_relaxed(
+                       ((tag[0] - 1) << L2X0_LATENCY_CTRL_RD_SHIFT) |
+                       ((tag[1] - 1) << L2X0_LATENCY_CTRL_WR_SHIFT) |
+                       ((tag[2] - 1) << L2X0_LATENCY_CTRL_SETUP_SHIFT),
+                       l2x0_base + L2X0_TAG_LATENCY_CTRL);
+
+       of_property_read_u32_array(np, "arm,data-latency",
+                                  data, ARRAY_SIZE(data));
+       if (data[0] && data[1] && data[2])
+               writel_relaxed(
+                       ((data[0] - 1) << L2X0_LATENCY_CTRL_RD_SHIFT) |
+                       ((data[1] - 1) << L2X0_LATENCY_CTRL_WR_SHIFT) |
+                       ((data[2] - 1) << L2X0_LATENCY_CTRL_SETUP_SHIFT),
+                       l2x0_base + L2X0_DATA_LATENCY_CTRL);
+
+       of_property_read_u32_array(np, "arm,filter-ranges",
+                                  filter, ARRAY_SIZE(filter));
+       if (filter[0] && filter[1]) {
+               writel_relaxed(ALIGN(filter[0] + filter[1], SZ_1M),
+                              l2x0_base + L2X0_ADDR_FILTER_END);
+               writel_relaxed((filter[0] & ~(SZ_1M - 1)) | L2X0_ADDR_FILTER_EN,
+                              l2x0_base + L2X0_ADDR_FILTER_START);
+       }
+}
+
+static const struct of_device_id l2x0_ids[] __initconst = {
+       { .compatible = "arm,pl310-cache", .data = pl310_of_setup },
+       { .compatible = "arm,l220-cache", .data = l2x0_of_setup },
+       { .compatible = "arm,l210-cache", .data = l2x0_of_setup },
+       {}
+};
+
+int __init l2x0_of_init(__u32 aux_val, __u32 aux_mask)
+{
+       struct device_node *np;
+       void (*l2_setup)(const struct device_node *np,
+               __u32 *aux_val, __u32 *aux_mask);
+
+       np = of_find_matching_node(NULL, l2x0_ids);
+       if (!np)
+               return -ENODEV;
+       l2x0_base = of_iomap(np, 0);
+       if (!l2x0_base)
+               return -ENOMEM;
+
+       /* L2 configuration can only be changed if the cache is disabled */
+       if (!(readl_relaxed(l2x0_base + L2X0_CTRL) & 1)) {
+               l2_setup = of_match_node(l2x0_ids, np)->data;
+               if (l2_setup)
+                       l2_setup(np, &aux_val, &aux_mask);
+       }
+       l2x0_init(l2x0_base, aux_val, aux_mask);
+       return 0;
+}
+#endif