[PATCH v2] clk: shmobile: sh73a0 common clock framework implementation
Ulrich Hecht
ulrich.hecht at gmail.com
Mon Jun 2 07:54:58 PDT 2014
Driver for the SH73A0's clocks that are too specific to be supported by a
generic driver.
Signed-off-by: Ulrich Hecht <ulrich.hecht+renesas at gmail.com>
---
Changes since v1:
- reshuffled to include DT bindings and Makefile changes
- reformatted register addresses and divider masks
- marked bindings as experimental
- use div4_clk::parent instead of hardcoding them
.../bindings/clock/renesas,sh73a0-cpg-clocks.txt | 31 ++++
drivers/clk/shmobile/Makefile | 1 +
drivers/clk/shmobile/clk-sh73a0.c | 199 +++++++++++++++++++++
3 files changed, 231 insertions(+)
create mode 100644 Documentation/devicetree/bindings/clock/renesas,sh73a0-cpg-clocks.txt
create mode 100644 drivers/clk/shmobile/clk-sh73a0.c
diff --git a/Documentation/devicetree/bindings/clock/renesas,sh73a0-cpg-clocks.txt b/Documentation/devicetree/bindings/clock/renesas,sh73a0-cpg-clocks.txt
new file mode 100644
index 0000000..6b8dece
--- /dev/null
+++ b/Documentation/devicetree/bindings/clock/renesas,sh73a0-cpg-clocks.txt
@@ -0,0 +1,31 @@
+These bindings should be considered EXPERIMENTAL for now.
+
+* Renesas SH73A0 Clock Pulse Generator (CPG)
+
+The CPG generates core clocks for the SH73A0 SoC. It includes four PLLs
+and several fixed ratio dividers.
+
+Required Properties:
+
+ - compatible: Must be "renesas,sh73a0-cpg-clocks"
+
+ - reg: Base address and length of the memory resource used by the CPG
+
+ - clocks: Reference to the parent clocks
+ - #clock-cells: Must be 1
+ - clock-output-names: The names of the clocks. Supported clocks are "main",
+ "pll0", "pll1", "pll2", "pll3", "z", "dsi0phy", "dsi1phy", and "twd"
+
+
+Example
+-------
+
+ cpg_clocks: cpg_clocks at e6150000 {
+ compatible = "renesas,sh73a0-cpg-clocks";
+ reg = <0 0xe6150000 0 0x10000>;
+ clocks = <&extal1_clk>, <&extal2_clk>;
+ #clock-cells = <1>;
+ clock-output-names = "main", "pll0", "pll1", "pll2",
+ "pll3", "z", "dsi0phy", "dsi1phy",
+ "twd";
+ };
diff --git a/drivers/clk/shmobile/Makefile b/drivers/clk/shmobile/Makefile
index bdf342d..6a54e73 100644
--- a/drivers/clk/shmobile/Makefile
+++ b/drivers/clk/shmobile/Makefile
@@ -3,6 +3,7 @@ obj-$(CONFIG_ARCH_R7S72100) += clk-rz.o
obj-$(CONFIG_ARCH_R8A7779) += clk-r8a7779.o
obj-$(CONFIG_ARCH_R8A7790) += clk-rcar-gen2.o
obj-$(CONFIG_ARCH_R8A7791) += clk-rcar-gen2.o
+obj-$(CONFIG_ARCH_SH73A0) += clk-sh73a0.o
obj-$(CONFIG_ARCH_SHMOBILE_MULTI) += clk-div6.o
obj-$(CONFIG_ARCH_SHMOBILE_MULTI) += clk-mstp.o
# for emply built-in.o
diff --git a/drivers/clk/shmobile/clk-sh73a0.c b/drivers/clk/shmobile/clk-sh73a0.c
new file mode 100644
index 0000000..0310de2
--- /dev/null
+++ b/drivers/clk/shmobile/clk-sh73a0.c
@@ -0,0 +1,199 @@
+/*
+ * sh73a0 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/init.h>
+#include <linux/kernel.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/spinlock.h>
+
+struct sh73a0_cpg {
+ struct clk_onecell_data data;
+ spinlock_t lock;
+ void __iomem *reg;
+};
+
+#define CPG_FRQCRA 0x00
+#define CPG_FRQCRB 0x04
+#define CPG_SD0CKCR 0x74
+#define CPG_SD1CKCR 0x78
+#define CPG_SD2CKCR 0x7c
+#define CPG_PLLECR 0xd0
+#define CPG_PLL0CR 0xd8
+#define CPG_PLL1CR 0x28
+#define CPG_PLL2CR 0x2c
+#define CPG_PLL3CR 0xdc
+#define CPG_CKSCR 0xc0
+#define CPG_DSI0PHYCR 0x6c
+#define CPG_DSI1PHYCR 0x70
+
+#define CLK_ENABLE_ON_INIT BIT(0)
+
+struct div4_clk {
+ const char *name;
+ const char *parent;
+ unsigned int reg;
+ unsigned int shift;
+ unsigned int mask;
+ int flags;
+};
+
+static struct div4_clk div4_clks[] = {
+ { "zg", "pll0", CPG_FRQCRA, 16, 0x0d7f, CLK_ENABLE_ON_INIT },
+ { "m3", "pll1", CPG_FRQCRA, 12, 0x1dff, CLK_ENABLE_ON_INIT },
+ { "b", "pll1", CPG_FRQCRA, 8, 0x0dff, CLK_ENABLE_ON_INIT },
+ { "m1", "pll1", CPG_FRQCRA, 4, 0x1dff, 0 },
+ { "m2", "pll1", CPG_FRQCRA, 0, 0x1dff, 0 },
+ { "z", "pll0", CPG_FRQCRB, 24, 0x097f, 0 },
+ { "zx", "pll1", CPG_FRQCRB, 12, 0x0dff, 0 },
+ { "hp", "pll1", CPG_FRQCRB, 4, 0x0dff, 0 },
+ { NULL, 0, 0, 0, 0 },
+};
+
+static const struct clk_div_table div4_div_table[] = {
+ { 0, 2 }, { 1, 3 }, { 2, 4 }, { 3, 6 }, { 4, 8 }, { 5, 12 },
+ { 6, 16 }, { 7, 18 }, { 8, 24 }, { 10, 36 }, { 11, 48 },
+ { 12, 7 }, { 0, 0 }
+};
+
+static struct clk * __init
+sh73a0_cpg_register_clock(struct device_node *np, struct sh73a0_cpg *cpg,
+ const char *name)
+{
+ const struct clk_div_table *table = NULL;
+ const char *parent_name;
+ unsigned int shift, reg;
+ unsigned int mult = 1;
+ unsigned int div = 1;
+
+ if (!strcmp(name, "main")) {
+ /* extal1, extal1_div2, extal2, extal2_div2 */
+ parent_name = of_clk_get_parent_name(np,
+ (clk_readl(cpg->reg + CPG_CKSCR) >> 28) & 3);
+ } else if (!strncmp(name, "pll", 3)) {
+ void __iomem *enable_reg = cpg->reg;
+ u32 enable_bit = name[3] - '0';
+ parent_name = "main";
+ switch (enable_bit) {
+ case 0:
+ enable_reg += CPG_PLL0CR;
+ break;
+ case 1:
+ enable_reg += CPG_PLL1CR;
+ break;
+ case 2:
+ enable_reg += CPG_PLL2CR;
+ break;
+ case 3:
+ enable_reg += CPG_PLL3CR;
+ break;
+ default:
+ return ERR_PTR(-EINVAL);
+ }
+ if (clk_readl(cpg->reg + CPG_PLLECR) & BIT(enable_bit)) {
+ mult = ((clk_readl(enable_reg) >> 24) & 0x3f) + 1;
+ /* handle CFG bit for PLL1 and PLL2 */
+ if (enable_bit == 1 || enable_bit == 2)
+ if (clk_readl(enable_reg) & BIT(20))
+ mult *= 2;
+ }
+ } else if (!strcmp(name, "dsi0phy") || !strcmp(name, "dsi1phy")) {
+ u32 phy_no = name[3] - '0';
+ void __iomem *dsi_reg = cpg->reg +
+ (phy_no ? CPG_DSI1PHYCR : CPG_DSI0PHYCR);
+ parent_name = phy_no ? "dsi1pck" : "dsi0pck";
+ div = __raw_readl(dsi_reg);
+ if (!(div & 0xb8000))
+ div = 1;
+ else
+ div = (div & 0x3f) + 1;
+ } else {
+ struct div4_clk *c;
+ for (c = div4_clks; c->name; c++) {
+ if (!strcmp(name, c->name)) {
+ parent_name = c->parent;
+ table = div4_div_table;
+ reg = c->reg;
+ shift = c->shift;
+ break;
+ }
+ }
+ if (!c->name)
+ return ERR_PTR(-EINVAL);
+ }
+
+ if (!table) {
+ return clk_register_fixed_factor(NULL, name, parent_name, 0,
+ mult, div);
+ } else {
+ return clk_register_divider_table(NULL, name, parent_name, 0,
+ cpg->reg + reg, shift, 4, 0,
+ table, &cpg->lock);
+ }
+}
+
+static void __init sh73a0_cpg_clocks_init(struct device_node *np)
+{
+ struct sh73a0_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 = kzalloc(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;
+
+ /* Set SDHI clocks to a known state */
+ clk_writel(0x108, cpg->reg + CPG_SD0CKCR);
+ clk_writel(0x108, cpg->reg + CPG_SD1CKCR);
+ clk_writel(0x108, cpg->reg + CPG_SD2CKCR);
+
+ 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 = sh73a0_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(sh73a0_cpg_clks, "renesas,sh73a0-cpg-clocks",
+ sh73a0_cpg_clocks_init);
--
1.8.4.5
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