[PATCH 03/12] clk: versatile: add basic clocks
Lucas Stach
l.stach at pengutronix.de
Fri Sep 15 01:39:13 PDT 2017
This adds the necessary basic clocks used on the ARM versatile
platforms.
Signed-off-by: Lucas Stach <l.stach at pengutronix.de>
---
drivers/clk/Makefile | 1 +
drivers/clk/vexpress/Makefile | 1 +
drivers/clk/vexpress/clk-sp810.c | 137 ++++++++++++++++++++++++++++++++
drivers/clk/vexpress/clk-vexpress-osc.c | 42 ++++++++++
4 files changed, 181 insertions(+)
create mode 100644 drivers/clk/vexpress/Makefile
create mode 100644 drivers/clk/vexpress/clk-sp810.c
create mode 100644 drivers/clk/vexpress/clk-vexpress-osc.c
diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
index b5abe1cdf5db..a36a8db03bdb 100644
--- a/drivers/clk/Makefile
+++ b/drivers/clk/Makefile
@@ -12,3 +12,4 @@ obj-$(CONFIG_CLK_SOCFPGA) += socfpga/
obj-$(CONFIG_MACH_MIPS_ATH79) += clk-ar933x.o
obj-$(CONFIG_ARCH_IMX) += imx/
obj-$(CONFIG_COMMON_CLK_AT91) += at91/
+obj-$(CONFIG_MACH_VEXPRESS) += vexpress/
diff --git a/drivers/clk/vexpress/Makefile b/drivers/clk/vexpress/Makefile
new file mode 100644
index 000000000000..c6869bac8365
--- /dev/null
+++ b/drivers/clk/vexpress/Makefile
@@ -0,0 +1 @@
+obj-y += clk-vexpress-osc.o clk-sp810.o
diff --git a/drivers/clk/vexpress/clk-sp810.c b/drivers/clk/vexpress/clk-sp810.c
new file mode 100644
index 000000000000..dc57b74e0848
--- /dev/null
+++ b/drivers/clk/vexpress/clk-sp810.c
@@ -0,0 +1,137 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * Copyright (C) 2013 ARM Limited
+ */
+
+//#include <linux/amba/sp810.h>
+#include <common.h>
+#include <io.h>
+#include <malloc.h>
+#include <of_address.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+
+/* sysctl registers offset */
+#define SCCTRL 0x000
+#define SCCTRL_TIMERENnSEL_SHIFT(n) (15 + ((n) * 2))
+
+struct clk_sp810;
+
+struct clk_sp810_timerclken {
+ struct clk hw;
+ struct clk_sp810 *sp810;
+ int channel;
+};
+
+static inline struct clk_sp810_timerclken *
+to_clk_sp810_timerclken(struct clk *clk)
+{
+ return container_of(clk, struct clk_sp810_timerclken, hw);
+}
+
+struct clk_sp810 {
+ struct device_node *node;
+ void __iomem *base;
+ struct clk_sp810_timerclken timerclken[4];
+};
+
+static int clk_sp810_timerclken_get_parent(struct clk *hw)
+{
+ struct clk_sp810_timerclken *timerclken = to_clk_sp810_timerclken(hw);
+ u32 val = readl(timerclken->sp810->base + SCCTRL);
+
+ return !!(val & (1 << SCCTRL_TIMERENnSEL_SHIFT(timerclken->channel)));
+}
+
+static int clk_sp810_timerclken_set_parent(struct clk *hw, u8 index)
+{
+ struct clk_sp810_timerclken *timerclken = to_clk_sp810_timerclken(hw);
+ struct clk_sp810 *sp810 = timerclken->sp810;
+ u32 val, shift = SCCTRL_TIMERENnSEL_SHIFT(timerclken->channel);
+
+ if (WARN_ON(index > 1))
+ return -EINVAL;
+
+ val = readl(sp810->base + SCCTRL);
+ val &= ~(1 << shift);
+ val |= index << shift;
+ writel(val, sp810->base + SCCTRL);
+
+ return 0;
+}
+
+static const struct clk_ops clk_sp810_timerclken_ops = {
+ .get_parent = clk_sp810_timerclken_get_parent,
+ .set_parent = clk_sp810_timerclken_set_parent,
+};
+
+static struct clk *clk_sp810_timerclken_of_get(struct of_phandle_args *clkspec,
+ void *data)
+{
+ struct clk_sp810 *sp810 = data;
+
+ if (WARN_ON(clkspec->args_count != 1 ||
+ clkspec->args[0] >= ARRAY_SIZE(sp810->timerclken)))
+ return NULL;
+
+ return &sp810->timerclken[clkspec->args[0]].hw;
+}
+
+static void clk_sp810_of_setup(struct device_node *node)
+{
+ struct clk_sp810 *sp810 = xzalloc(sizeof(*sp810));
+ const char *parent_names[2];
+ int num = ARRAY_SIZE(parent_names);
+ char name[12];
+ static int instance;
+ int i;
+ bool deprecated;
+
+ if (!sp810)
+ return;
+
+ if (of_clk_parent_fill(node, parent_names, num) != num) {
+ pr_warn("Failed to obtain parent clocks for SP810!\n");
+ kfree(sp810);
+ return;
+ }
+
+ sp810->node = node;
+ sp810->base = of_iomap(node, 0);
+
+ deprecated = !of_find_property(node, "assigned-clock-parents", NULL);
+
+ for (i = 0; i < ARRAY_SIZE(sp810->timerclken); i++) {
+ snprintf(name, sizeof(name), "sp810_%d_%d", instance, i);
+
+ sp810->timerclken[i].sp810 = sp810;
+ sp810->timerclken[i].channel = i;
+ sp810->timerclken[i].hw.name = strdup(name);
+ sp810->timerclken[i].hw.parent_names = parent_names;
+ sp810->timerclken[i].hw.num_parents = num;
+ sp810->timerclken[i].hw.ops = &clk_sp810_timerclken_ops;
+
+ /*
+ * If DT isn't setting the parent, force it to be
+ * the 1 MHz clock without going through the framework.
+ * We do this before clk_register() so that it can determine
+ * the parent and setup the tree properly.
+ */
+ if (deprecated)
+ clk_sp810_timerclken_set_parent(&sp810->timerclken[i].hw, 1);
+
+ clk_register(&sp810->timerclken[i].hw);
+ }
+
+ of_clk_add_provider(node, clk_sp810_timerclken_of_get, sp810);
+ instance++;
+}
+CLK_OF_DECLARE(sp810, "arm,sp810", clk_sp810_of_setup);
diff --git a/drivers/clk/vexpress/clk-vexpress-osc.c b/drivers/clk/vexpress/clk-vexpress-osc.c
new file mode 100644
index 000000000000..c0d6e6066ecd
--- /dev/null
+++ b/drivers/clk/vexpress/clk-vexpress-osc.c
@@ -0,0 +1,42 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <common.h>
+#include <malloc.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+
+/*
+ * This represents the vexpress-osc as a fixed clock, which isn't really
+ * accurate, as this clock allows rate changes in real implementations. As those
+ * would need access to the config bus, a whole lot more infrastructure would be
+ * needed. We skip this complication for now, as we don't have a use-case, yet.
+ */
+static int vexpress_osc_setup(struct device_node *node)
+{
+ struct clk *clk;
+ u32 range[2];
+ const char *name;
+
+ if (of_property_read_u32_array(node, "freq-range", range,
+ ARRAY_SIZE(range)))
+ return -EINVAL;
+
+ if (of_property_read_string(node, "clock-output-names", &name))
+ return -EINVAL;
+
+ clk = clk_fixed(name, range[0]);
+ if (IS_ERR(clk))
+ return PTR_ERR(clk);
+
+ return of_clk_add_provider(node, of_clk_src_simple_get, clk);
+}
+CLK_OF_DECLARE(vexpress_osc, "arm,vexpress-osc", vexpress_osc_setup);
--
2.11.0
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