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-rw-r--r--kernel/drivers/clk/shmobile/clk-emev2.c104
1 files changed, 104 insertions, 0 deletions
diff --git a/kernel/drivers/clk/shmobile/clk-emev2.c b/kernel/drivers/clk/shmobile/clk-emev2.c
new file mode 100644
index 000000000..6c7c929c7
--- /dev/null
+++ b/kernel/drivers/clk/shmobile/clk-emev2.c
@@ -0,0 +1,104 @@
+/*
+ * EMMA Mobile EV2 common clock framework support
+ *
+ * Copyright (C) 2013 Takashi Yoshii <takashi.yoshii.ze@renesas.com>
+ * Copyright (C) 2012 Magnus Damm
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+#include <linux/clk-provider.h>
+#include <linux/clkdev.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+
+/* EMEV2 SMU registers */
+#define USIAU0_RSTCTRL 0x094
+#define USIBU1_RSTCTRL 0x0ac
+#define USIBU2_RSTCTRL 0x0b0
+#define USIBU3_RSTCTRL 0x0b4
+#define STI_RSTCTRL 0x124
+#define STI_CLKSEL 0x688
+
+static DEFINE_SPINLOCK(lock);
+
+/* not pretty, but hey */
+void __iomem *smu_base;
+
+static void __init emev2_smu_write(unsigned long value, int offs)
+{
+ BUG_ON(!smu_base || (offs >= PAGE_SIZE));
+ writel_relaxed(value, smu_base + offs);
+}
+
+static const struct of_device_id smu_id[] __initconst = {
+ { .compatible = "renesas,emev2-smu", },
+ {},
+};
+
+static void __init emev2_smu_init(void)
+{
+ struct device_node *np;
+
+ np = of_find_matching_node(NULL, smu_id);
+ BUG_ON(!np);
+ smu_base = of_iomap(np, 0);
+ BUG_ON(!smu_base);
+ of_node_put(np);
+
+ /* setup STI timer to run on 32.768 kHz and deassert reset */
+ emev2_smu_write(0, STI_CLKSEL);
+ emev2_smu_write(1, STI_RSTCTRL);
+
+ /* deassert reset for UART0->UART3 */
+ emev2_smu_write(2, USIAU0_RSTCTRL);
+ emev2_smu_write(2, USIBU1_RSTCTRL);
+ emev2_smu_write(2, USIBU2_RSTCTRL);
+ emev2_smu_write(2, USIBU3_RSTCTRL);
+}
+
+static void __init emev2_smu_clkdiv_init(struct device_node *np)
+{
+ u32 reg[2];
+ struct clk *clk;
+ const char *parent_name = of_clk_get_parent_name(np, 0);
+ if (WARN_ON(of_property_read_u32_array(np, "reg", reg, 2)))
+ return;
+ if (!smu_base)
+ emev2_smu_init();
+ clk = clk_register_divider(NULL, np->name, parent_name, 0,
+ smu_base + reg[0], reg[1], 8, 0, &lock);
+ of_clk_add_provider(np, of_clk_src_simple_get, clk);
+ clk_register_clkdev(clk, np->name, NULL);
+ pr_debug("## %s %s %p\n", __func__, np->name, clk);
+}
+CLK_OF_DECLARE(emev2_smu_clkdiv, "renesas,emev2-smu-clkdiv",
+ emev2_smu_clkdiv_init);
+
+static void __init emev2_smu_gclk_init(struct device_node *np)
+{
+ u32 reg[2];
+ struct clk *clk;
+ const char *parent_name = of_clk_get_parent_name(np, 0);
+ if (WARN_ON(of_property_read_u32_array(np, "reg", reg, 2)))
+ return;
+ if (!smu_base)
+ emev2_smu_init();
+ clk = clk_register_gate(NULL, np->name, parent_name, 0,
+ smu_base + reg[0], reg[1], 0, &lock);
+ of_clk_add_provider(np, of_clk_src_simple_get, clk);
+ clk_register_clkdev(clk, np->name, NULL);
+ pr_debug("## %s %s %p\n", __func__, np->name, clk);
+}
+CLK_OF_DECLARE(emev2_smu_gclk, "renesas,emev2-smu-gclk", emev2_smu_gclk_init);