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path: root/drivers/clk/versatile/clk-vexpress.c
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Diffstat (limited to 'drivers/clk/versatile/clk-vexpress.c')
-rw-r--r--drivers/clk/versatile/clk-vexpress.c142
1 files changed, 142 insertions, 0 deletions
diff --git a/drivers/clk/versatile/clk-vexpress.c b/drivers/clk/versatile/clk-vexpress.c
new file mode 100644
index 000000000000..c742ac7c60bb
--- /dev/null
+++ b/drivers/clk/versatile/clk-vexpress.c
@@ -0,0 +1,142 @@
+/*
+ * 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) 2012 ARM Limited
+ */
+
+#include <linux/clkdev.h>
+#include <linux/clk-provider.h>
+#include <linux/err.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/vexpress.h>
+
+#include <asm/hardware/sp810.h>
+
+static struct clk *vexpress_sp810_timerclken[4];
+static DEFINE_SPINLOCK(vexpress_sp810_lock);
+
+static void __init vexpress_sp810_init(void __iomem *base)
+{
+ int i;
+
+ if (WARN_ON(!base))
+ return;
+
+ for (i = 0; i < ARRAY_SIZE(vexpress_sp810_timerclken); i++) {
+ char name[12];
+ const char *parents[] = {
+ "v2m:refclk32khz", /* REFCLK */
+ "v2m:refclk1mhz" /* TIMCLK */
+ };
+
+ snprintf(name, ARRAY_SIZE(name), "timerclken%d", i);
+
+ vexpress_sp810_timerclken[i] = clk_register_mux(NULL, name,
+ parents, 2, 0, base + SCCTRL,
+ SCCTRL_TIMERENnSEL_SHIFT(i), 1,
+ 0, &vexpress_sp810_lock);
+
+ if (WARN_ON(IS_ERR(vexpress_sp810_timerclken[i])))
+ break;
+ }
+}
+
+
+static const char * const vexpress_clk_24mhz_periphs[] __initconst = {
+ "mb:uart0", "mb:uart1", "mb:uart2", "mb:uart3",
+ "mb:mmci", "mb:kmi0", "mb:kmi1"
+};
+
+void __init vexpress_clk_init(void __iomem *sp810_base)
+{
+ struct clk *clk;
+ int i;
+
+ clk = clk_register_fixed_rate(NULL, "dummy_apb_pclk", NULL,
+ CLK_IS_ROOT, 0);
+ WARN_ON(clk_register_clkdev(clk, "apb_pclk", NULL));
+
+ clk = clk_register_fixed_rate(NULL, "v2m:clk_24mhz", NULL,
+ CLK_IS_ROOT, 24000000);
+ for (i = 0; i < ARRAY_SIZE(vexpress_clk_24mhz_periphs); i++)
+ WARN_ON(clk_register_clkdev(clk, NULL,
+ vexpress_clk_24mhz_periphs[i]));
+
+ clk = clk_register_fixed_rate(NULL, "v2m:refclk32khz", NULL,
+ CLK_IS_ROOT, 32768);
+ WARN_ON(clk_register_clkdev(clk, NULL, "v2m:wdt"));
+
+ clk = clk_register_fixed_rate(NULL, "v2m:refclk1mhz", NULL,
+ CLK_IS_ROOT, 1000000);
+
+ vexpress_sp810_init(sp810_base);
+
+ for (i = 0; i < ARRAY_SIZE(vexpress_sp810_timerclken); i++)
+ WARN_ON(clk_set_parent(vexpress_sp810_timerclken[i], clk));
+
+ WARN_ON(clk_register_clkdev(vexpress_sp810_timerclken[0],
+ "v2m-timer0", "sp804"));
+ WARN_ON(clk_register_clkdev(vexpress_sp810_timerclken[1],
+ "v2m-timer1", "sp804"));
+}
+
+#if defined(CONFIG_OF)
+
+struct clk *vexpress_sp810_of_get(struct of_phandle_args *clkspec, void *data)
+{
+ if (WARN_ON(clkspec->args_count != 1 || clkspec->args[0] >
+ ARRAY_SIZE(vexpress_sp810_timerclken)))
+ return NULL;
+
+ return vexpress_sp810_timerclken[clkspec->args[0]];
+}
+
+static const __initconst struct of_device_id vexpress_fixed_clk_match[] = {
+ { .compatible = "fixed-clock", .data = of_fixed_clk_setup, },
+ { .compatible = "arm,vexpress-osc", .data = vexpress_osc_of_setup, },
+ {}
+};
+
+void __init vexpress_clk_of_init(void)
+{
+ struct device_node *node;
+ struct clk *clk;
+ struct clk *refclk, *timclk;
+
+ of_clk_init(vexpress_fixed_clk_match);
+
+ node = of_find_compatible_node(NULL, NULL, "arm,sp810");
+ vexpress_sp810_init(of_iomap(node, 0));
+ of_clk_add_provider(node, vexpress_sp810_of_get, NULL);
+
+ /* Select "better" (faster) parent for SP804 timers */
+ refclk = of_clk_get_by_name(node, "refclk");
+ timclk = of_clk_get_by_name(node, "timclk");
+ if (!WARN_ON(IS_ERR(refclk) || IS_ERR(timclk))) {
+ int i = 0;
+
+ if (clk_get_rate(refclk) > clk_get_rate(timclk))
+ clk = refclk;
+ else
+ clk = timclk;
+
+ for (i = 0; i < ARRAY_SIZE(vexpress_sp810_timerclken); i++)
+ WARN_ON(clk_set_parent(vexpress_sp810_timerclken[i],
+ clk));
+ }
+
+ WARN_ON(clk_register_clkdev(vexpress_sp810_timerclken[0],
+ "v2m-timer0", "sp804"));
+ WARN_ON(clk_register_clkdev(vexpress_sp810_timerclken[1],
+ "v2m-timer1", "sp804"));
+}
+
+#endif