[PATCH 11/16] ARM: shmobile: r8a7778: common clock framework CPG driver
Simon Horman
horms+renesas at verge.net.au
Wed Mar 4 17:58:11 PST 2015
From: Ulrich Hecht <ulrich.hecht+renesas at gmail.com>
Driver for the r8a7778's clocks that depend on the mode bits.
Signed-off-by: Ulrich Hecht <ulrich.hecht+renesas at gmail.com>
Acked-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
Acked-by: Michael Turquette <mturquette at linaro.org>
Signed-off-by: Simon Horman <horms+renesas at verge.net.au>
---
.../bindings/clock/renesas,r8a7778-cpg-clocks.txt | 25 ++++
drivers/clk/shmobile/Makefile | 1 +
drivers/clk/shmobile/clk-r8a7778.c | 143 +++++++++++++++++++++
include/linux/clk/shmobile.h | 1 +
4 files changed, 170 insertions(+)
create mode 100644 Documentation/devicetree/bindings/clock/renesas,r8a7778-cpg-clocks.txt
create mode 100644 drivers/clk/shmobile/clk-r8a7778.c
diff --git a/Documentation/devicetree/bindings/clock/renesas,r8a7778-cpg-clocks.txt b/Documentation/devicetree/bindings/clock/renesas,r8a7778-cpg-clocks.txt
new file mode 100644
index 0000000..2f3747f
--- /dev/null
+++ b/Documentation/devicetree/bindings/clock/renesas,r8a7778-cpg-clocks.txt
@@ -0,0 +1,25 @@
+* Renesas R8A7778 Clock Pulse Generator (CPG)
+
+The CPG generates core clocks for the R8A7778. It includes two PLLs and
+several fixed ratio dividers
+
+Required Properties:
+
+ - compatible: Must be "renesas,r8a7778-cpg-clocks"
+ - reg: Base address and length of the memory resource used by the CPG
+ - #clock-cells: Must be 1
+ - clock-output-names: The names of the clocks. Supported clocks are
+ "plla", "pllb", "b", "out", "p", "s", and "s1".
+
+
+Example
+-------
+
+ cpg_clocks: cpg_clocks at ffc80000 {
+ compatible = "renesas,r8a7778-cpg-clocks";
+ reg = <0xffc80000 0x80>;
+ #clock-cells = <1>;
+ clocks = <&extal_clk>;
+ clock-output-names = "plla", "pllb", "b",
+ "out", "p", "s", "s1";
+ };
diff --git a/drivers/clk/shmobile/Makefile b/drivers/clk/shmobile/Makefile
index 0689d7f..97c71c8 100644
--- a/drivers/clk/shmobile/Makefile
+++ b/drivers/clk/shmobile/Makefile
@@ -2,6 +2,7 @@ obj-$(CONFIG_ARCH_EMEV2) += clk-emev2.o
obj-$(CONFIG_ARCH_R7S72100) += clk-rz.o
obj-$(CONFIG_ARCH_R8A73A4) += clk-r8a73a4.o
obj-$(CONFIG_ARCH_R8A7740) += clk-r8a7740.o
+obj-$(CONFIG_ARCH_R8A7778) += clk-r8a7778.o
obj-$(CONFIG_ARCH_R8A7779) += clk-r8a7779.o
obj-$(CONFIG_ARCH_R8A7790) += clk-rcar-gen2.o
obj-$(CONFIG_ARCH_R8A7791) += clk-rcar-gen2.o
diff --git a/drivers/clk/shmobile/clk-r8a7778.c b/drivers/clk/shmobile/clk-r8a7778.c
new file mode 100644
index 0000000..cb33b57
--- /dev/null
+++ b/drivers/clk/shmobile/clk-r8a7778.c
@@ -0,0 +1,143 @@
+/*
+ * r8a7778 Core CPG Clocks
+ *
+ * Copyright (C) 2014 Ulrich Hecht
+ *
+ * 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.
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/clkdev.h>
+#include <linux/clk/shmobile.h>
+#include <linux/of_address.h>
+
+struct r8a7778_cpg {
+ struct clk_onecell_data data;
+ spinlock_t lock;
+ void __iomem *reg;
+};
+
+/* PLL multipliers per bits 11, 12, and 18 of MODEMR */
+struct {
+ unsigned long plla_mult;
+ unsigned long pllb_mult;
+} r8a7778_rates[] __initdata = {
+ [0] = { 21, 21 },
+ [1] = { 24, 24 },
+ [2] = { 28, 28 },
+ [3] = { 32, 32 },
+ [5] = { 24, 21 },
+ [6] = { 28, 21 },
+ [7] = { 32, 24 },
+};
+
+/* Clock dividers per bits 1 and 2 of MODEMR */
+struct {
+ const char *name;
+ unsigned int div[4];
+} r8a7778_divs[6] __initdata = {
+ { "b", { 12, 12, 16, 18 } },
+ { "out", { 12, 12, 16, 18 } },
+ { "p", { 16, 12, 16, 12 } },
+ { "s", { 4, 3, 4, 3 } },
+ { "s1", { 8, 6, 8, 6 } },
+};
+
+static u32 cpg_mode_rates __initdata;
+static u32 cpg_mode_divs __initdata;
+
+static struct clk * __init
+r8a7778_cpg_register_clock(struct device_node *np, struct r8a7778_cpg *cpg,
+ const char *name)
+{
+ if (!strcmp(name, "plla")) {
+ return clk_register_fixed_factor(NULL, "plla",
+ of_clk_get_parent_name(np, 0), 0,
+ r8a7778_rates[cpg_mode_rates].plla_mult, 1);
+ } else if (!strcmp(name, "pllb")) {
+ return clk_register_fixed_factor(NULL, "pllb",
+ of_clk_get_parent_name(np, 0), 0,
+ r8a7778_rates[cpg_mode_rates].pllb_mult, 1);
+ } else {
+ unsigned int i;
+
+ for (i = 0; i < ARRAY_SIZE(r8a7778_divs); i++) {
+ if (!strcmp(name, r8a7778_divs[i].name)) {
+ return clk_register_fixed_factor(NULL,
+ r8a7778_divs[i].name,
+ "plla", 0, 1,
+ r8a7778_divs[i].div[cpg_mode_divs]);
+ }
+ }
+ }
+
+ return ERR_PTR(-EINVAL);
+}
+
+
+static void __init r8a7778_cpg_clocks_init(struct device_node *np)
+{
+ struct r8a7778_cpg *cpg;
+ struct clk **clks;
+ unsigned int i;
+ int num_clks;
+
+ num_clks = of_property_count_strings(np, "clock-output-names");
+ if (num_clks < 0) {
+ pr_err("%s: failed to count clocks\n", __func__);
+ return;
+ }
+
+ cpg = kzalloc(sizeof(*cpg), GFP_KERNEL);
+ clks = kcalloc(num_clks, sizeof(*clks), GFP_KERNEL);
+ if (cpg == NULL || clks == NULL) {
+ /* We're leaking memory on purpose, there's no point in cleaning
+ * up as the system won't boot anyway.
+ */
+ return;
+ }
+
+ spin_lock_init(&cpg->lock);
+
+ cpg->data.clks = clks;
+ cpg->data.clk_num = num_clks;
+
+ cpg->reg = of_iomap(np, 0);
+ if (WARN_ON(cpg->reg == NULL))
+ return;
+
+ for (i = 0; i < num_clks; ++i) {
+ const char *name;
+ struct clk *clk;
+
+ of_property_read_string_index(np, "clock-output-names", i,
+ &name);
+
+ clk = r8a7778_cpg_register_clock(np, cpg, name);
+ if (IS_ERR(clk))
+ pr_err("%s: failed to register %s %s clock (%ld)\n",
+ __func__, np->name, name, PTR_ERR(clk));
+ else
+ cpg->data.clks[i] = clk;
+ }
+
+ of_clk_add_provider(np, of_clk_src_onecell_get, &cpg->data);
+}
+
+CLK_OF_DECLARE(r8a7778_cpg_clks, "renesas,r8a7778-cpg-clocks",
+ r8a7778_cpg_clocks_init);
+
+void __init r8a7778_clocks_init(u32 mode)
+{
+ BUG_ON(!(mode & BIT(19)));
+
+ cpg_mode_rates = (!!(mode & BIT(18)) << 2) |
+ (!!(mode & BIT(12)) << 1) |
+ (!!(mode & BIT(11)));
+ cpg_mode_divs = (!!(mode & BIT(2)) << 1) |
+ (!!(mode & BIT(1)));
+
+ of_clk_init(NULL);
+}
diff --git a/include/linux/clk/shmobile.h b/include/linux/clk/shmobile.h
index 9f8a140..63a8159 100644
--- a/include/linux/clk/shmobile.h
+++ b/include/linux/clk/shmobile.h
@@ -16,6 +16,7 @@
#include <linux/types.h>
+void r8a7778_clocks_init(u32 mode);
void r8a7779_clocks_init(u32 mode);
void rcar_gen2_clocks_init(u32 mode);
--
2.1.4
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