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-rw-r--r--drivers/clk/versatile/Makefile2
-rw-r--r--drivers/clk/versatile/clk-vexpress-spc.c131
2 files changed, 132 insertions, 1 deletions
diff --git a/drivers/clk/versatile/Makefile b/drivers/clk/versatile/Makefile
index c16ca787170..6e76bf87ca8 100644
--- a/drivers/clk/versatile/Makefile
+++ b/drivers/clk/versatile/Makefile
@@ -4,4 +4,4 @@ obj-$(CONFIG_ARCH_INTEGRATOR) += clk-integrator.o
obj-$(CONFIG_INTEGRATOR_IMPD1) += clk-impd1.o
obj-$(CONFIG_ARCH_REALVIEW) += clk-realview.o
obj-$(CONFIG_ARCH_VEXPRESS) += clk-vexpress.o clk-sp810.o
-obj-$(CONFIG_VEXPRESS_CONFIG) += clk-vexpress-osc.o
+obj-$(CONFIG_VEXPRESS_CONFIG) += clk-vexpress-osc.o clk-vexpress-spc.o
diff --git a/drivers/clk/versatile/clk-vexpress-spc.c b/drivers/clk/versatile/clk-vexpress-spc.c
new file mode 100644
index 00000000000..b701ae41475
--- /dev/null
+++ b/drivers/clk/versatile/clk-vexpress-spc.c
@@ -0,0 +1,131 @@
+/*
+ * Copyright (C) 2012 ARM Limited
+ * Copyright (C) 2012 Linaro
+ *
+ * Author: Viresh Kumar <viresh.kumar@linaro.org>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+/* SPC clock programming interface for Vexpress cpus */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/clk-provider.h>
+#include <linux/clkdev.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/vexpress.h>
+
+struct clk_spc {
+ struct clk_hw hw;
+ spinlock_t *lock;
+ int cluster;
+};
+
+#define to_clk_spc(spc) container_of(spc, struct clk_spc, hw)
+
+static unsigned long spc_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct clk_spc *spc = to_clk_spc(hw);
+ u32 freq;
+
+ if (vexpress_spc_get_performance(spc->cluster, &freq)) {
+ return -EIO;
+ pr_err("%s: Failed", __func__);
+ }
+
+ return freq * 1000;
+}
+
+static long spc_round_rate(struct clk_hw *hw, unsigned long drate,
+ unsigned long *parent_rate)
+{
+ return drate;
+}
+
+static int spc_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct clk_spc *spc = to_clk_spc(hw);
+
+ return vexpress_spc_set_performance(spc->cluster, rate / 1000);
+}
+
+static struct clk_ops clk_spc_ops = {
+ .recalc_rate = spc_recalc_rate,
+ .round_rate = spc_round_rate,
+ .set_rate = spc_set_rate,
+};
+
+struct clk *vexpress_clk_register_spc(const char *name, int cluster_id)
+{
+ struct clk_init_data init;
+ struct clk_spc *spc;
+ struct clk *clk;
+
+ if (!name) {
+ pr_err("Invalid name passed");
+ return ERR_PTR(-EINVAL);
+ }
+
+ spc = kzalloc(sizeof(*spc), GFP_KERNEL);
+ if (!spc) {
+ pr_err("could not allocate spc clk\n");
+ return ERR_PTR(-ENOMEM);
+ }
+
+ spc->hw.init = &init;
+ spc->cluster = cluster_id;
+
+ init.name = name;
+ init.ops = &clk_spc_ops;
+ init.flags = CLK_IS_ROOT | CLK_GET_RATE_NOCACHE;
+ init.num_parents = 0;
+
+ clk = clk_register(NULL, &spc->hw);
+ if (!IS_ERR_OR_NULL(clk))
+ return clk;
+
+ pr_err("clk register failed\n");
+ kfree(spc);
+
+ return NULL;
+}
+
+#if defined(CONFIG_OF)
+void __init vexpress_clk_of_register_spc(void)
+{
+ char name[14] = "cpu-cluster.";
+ struct device_node *node = NULL;
+ struct clk *clk;
+ const u32 *val;
+ int cluster_id = 0, len;
+
+ if (!of_find_compatible_node(NULL, NULL, "arm,spc")) {
+ pr_debug("%s: No SPC found, Exiting!!\n", __func__);
+ return;
+ }
+
+ while ((node = of_find_node_by_name(node, "cluster"))) {
+ val = of_get_property(node, "reg", &len);
+ if (val && len == 4)
+ cluster_id = be32_to_cpup(val);
+
+ name[12] = cluster_id + '0';
+ clk = vexpress_clk_register_spc(name, cluster_id);
+ if (IS_ERR(clk))
+ return;
+
+ pr_debug("Registered clock '%s'\n", name);
+ clk_register_clkdev(clk, NULL, name);
+ }
+}
+CLK_OF_DECLARE(spc, "arm,spc", vexpress_clk_of_register_spc);
+#endif