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path: root/kernel/drivers/clk/ux500/clk-prcc.c
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-rw-r--r--kernel/drivers/clk/ux500/clk-prcc.c162
1 files changed, 162 insertions, 0 deletions
diff --git a/kernel/drivers/clk/ux500/clk-prcc.c b/kernel/drivers/clk/ux500/clk-prcc.c
new file mode 100644
index 000000000..0e950769e
--- /dev/null
+++ b/kernel/drivers/clk/ux500/clk-prcc.c
@@ -0,0 +1,162 @@
+/*
+ * PRCC clock implementation for ux500 platform.
+ *
+ * Copyright (C) 2012 ST-Ericsson SA
+ * Author: Ulf Hansson <ulf.hansson@linaro.org>
+ *
+ * License terms: GNU General Public License (GPL) version 2
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/err.h>
+#include <linux/types.h>
+
+#include "clk.h"
+
+#define PRCC_PCKEN 0x000
+#define PRCC_PCKDIS 0x004
+#define PRCC_KCKEN 0x008
+#define PRCC_KCKDIS 0x00C
+#define PRCC_PCKSR 0x010
+#define PRCC_KCKSR 0x014
+
+#define to_clk_prcc(_hw) container_of(_hw, struct clk_prcc, hw)
+
+struct clk_prcc {
+ struct clk_hw hw;
+ void __iomem *base;
+ u32 cg_sel;
+ int is_enabled;
+};
+
+/* PRCC clock operations. */
+
+static int clk_prcc_pclk_enable(struct clk_hw *hw)
+{
+ struct clk_prcc *clk = to_clk_prcc(hw);
+
+ writel(clk->cg_sel, (clk->base + PRCC_PCKEN));
+ while (!(readl(clk->base + PRCC_PCKSR) & clk->cg_sel))
+ cpu_relax();
+
+ clk->is_enabled = 1;
+ return 0;
+}
+
+static void clk_prcc_pclk_disable(struct clk_hw *hw)
+{
+ struct clk_prcc *clk = to_clk_prcc(hw);
+
+ writel(clk->cg_sel, (clk->base + PRCC_PCKDIS));
+ clk->is_enabled = 0;
+}
+
+static int clk_prcc_kclk_enable(struct clk_hw *hw)
+{
+ struct clk_prcc *clk = to_clk_prcc(hw);
+
+ writel(clk->cg_sel, (clk->base + PRCC_KCKEN));
+ while (!(readl(clk->base + PRCC_KCKSR) & clk->cg_sel))
+ cpu_relax();
+
+ clk->is_enabled = 1;
+ return 0;
+}
+
+static void clk_prcc_kclk_disable(struct clk_hw *hw)
+{
+ struct clk_prcc *clk = to_clk_prcc(hw);
+
+ writel(clk->cg_sel, (clk->base + PRCC_KCKDIS));
+ clk->is_enabled = 0;
+}
+
+static int clk_prcc_is_enabled(struct clk_hw *hw)
+{
+ struct clk_prcc *clk = to_clk_prcc(hw);
+ return clk->is_enabled;
+}
+
+static struct clk_ops clk_prcc_pclk_ops = {
+ .enable = clk_prcc_pclk_enable,
+ .disable = clk_prcc_pclk_disable,
+ .is_enabled = clk_prcc_is_enabled,
+};
+
+static struct clk_ops clk_prcc_kclk_ops = {
+ .enable = clk_prcc_kclk_enable,
+ .disable = clk_prcc_kclk_disable,
+ .is_enabled = clk_prcc_is_enabled,
+};
+
+static struct clk *clk_reg_prcc(const char *name,
+ const char *parent_name,
+ resource_size_t phy_base,
+ u32 cg_sel,
+ unsigned long flags,
+ struct clk_ops *clk_prcc_ops)
+{
+ struct clk_prcc *clk;
+ struct clk_init_data clk_prcc_init;
+ struct clk *clk_reg;
+
+ if (!name) {
+ pr_err("clk_prcc: %s invalid arguments passed\n", __func__);
+ return ERR_PTR(-EINVAL);
+ }
+
+ clk = kzalloc(sizeof(struct clk_prcc), GFP_KERNEL);
+ if (!clk) {
+ pr_err("clk_prcc: %s could not allocate clk\n", __func__);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ clk->base = ioremap(phy_base, SZ_4K);
+ if (!clk->base)
+ goto free_clk;
+
+ clk->cg_sel = cg_sel;
+ clk->is_enabled = 1;
+
+ clk_prcc_init.name = name;
+ clk_prcc_init.ops = clk_prcc_ops;
+ clk_prcc_init.flags = flags;
+ clk_prcc_init.parent_names = (parent_name ? &parent_name : NULL);
+ clk_prcc_init.num_parents = (parent_name ? 1 : 0);
+ clk->hw.init = &clk_prcc_init;
+
+ clk_reg = clk_register(NULL, &clk->hw);
+ if (IS_ERR_OR_NULL(clk_reg))
+ goto unmap_clk;
+
+ return clk_reg;
+
+unmap_clk:
+ iounmap(clk->base);
+free_clk:
+ kfree(clk);
+ pr_err("clk_prcc: %s failed to register clk\n", __func__);
+ return ERR_PTR(-ENOMEM);
+}
+
+struct clk *clk_reg_prcc_pclk(const char *name,
+ const char *parent_name,
+ resource_size_t phy_base,
+ u32 cg_sel,
+ unsigned long flags)
+{
+ return clk_reg_prcc(name, parent_name, phy_base, cg_sel, flags,
+ &clk_prcc_pclk_ops);
+}
+
+struct clk *clk_reg_prcc_kclk(const char *name,
+ const char *parent_name,
+ resource_size_t phy_base,
+ u32 cg_sel,
+ unsigned long flags)
+{
+ return clk_reg_prcc(name, parent_name, phy_base, cg_sel, flags,
+ &clk_prcc_kclk_ops);
+}