--- /dev/null
+* 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>;
+};
#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
* 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>
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