[PATCH v3] clk: add PowerPC corenet clock driver support
Yuantian.Tang at freescale.com
Yuantian.Tang at freescale.com
Tue Apr 9 18:46:26 EST 2013
From: Tang Yuantian <yuantian.tang at freescale.com>
This adds the clock driver for Freescale PowerPC corenet
series SoCs using common clock infrastructure.
Signed-off-by: Tang Yuantian <Yuantian.Tang at freescale.com>
Signed-off-by: Li Yang <leoli at freescale.com>
---
v3:
- remove the module author and description
v2:
- add the document for device tree clock bindings
arch/powerpc/platforms/Kconfig.cputype | 1 +
drivers/clk/Kconfig | 7 +
drivers/clk/Makefile | 1 +
drivers/clk/clk-ppc-corenet.c | 280 +++++++++++++++++++++++++++++++++
4 files changed, 289 insertions(+)
create mode 100644 drivers/clk/clk-ppc-corenet.c
diff --git a/arch/powerpc/platforms/Kconfig.cputype b/arch/powerpc/platforms/Kconfig.cputype
index 18e3b76..cf065b8 100644
--- a/arch/powerpc/platforms/Kconfig.cputype
+++ b/arch/powerpc/platforms/Kconfig.cputype
@@ -158,6 +158,7 @@ config E500
config PPC_E500MC
bool "e500mc Support"
select PPC_FPU
+ select COMMON_CLK
depends on E500
help
This must be enabled for running on e500mc (and derivatives
diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig
index a47e6ee..6e2fd9c 100644
--- a/drivers/clk/Kconfig
+++ b/drivers/clk/Kconfig
@@ -63,6 +63,13 @@ config CLK_TWL6040
McPDM. McPDM module is using the external bit clock on the McPDM bus
as functional clock.
+config CLK_PPC_CORENET
+ bool "Clock driver for PowerPC corenet platforms"
+ depends on PPC_E500MC && OF
+ ---help---
+ This adds the clock driver support for Freescale PowerPC corenet
+ platforms using common clock framework.
+
endmenu
source "drivers/clk/mvebu/Kconfig"
diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
index 300d477..6720319 100644
--- a/drivers/clk/Makefile
+++ b/drivers/clk/Makefile
@@ -34,3 +34,4 @@ obj-$(CONFIG_X86) += x86/
obj-$(CONFIG_COMMON_CLK_WM831X) += clk-wm831x.o
obj-$(CONFIG_COMMON_CLK_MAX77686) += clk-max77686.o
obj-$(CONFIG_CLK_TWL6040) += clk-twl6040.o
+obj-$(CONFIG_CLK_PPC_CORENET) += clk-ppc-corenet.o
diff --git a/drivers/clk/clk-ppc-corenet.c b/drivers/clk/clk-ppc-corenet.c
new file mode 100644
index 0000000..a2d483f
--- /dev/null
+++ b/drivers/clk/clk-ppc-corenet.c
@@ -0,0 +1,280 @@
+/*
+ * Copyright 2013 Freescale Semiconductor, Inc.
+ *
+ * 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.
+ *
+ * clock driver for Freescale PowerPC corenet SoCs.
+ */
+#include <linux/clk-provider.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_platform.h>
+#include <linux/of.h>
+#include <linux/slab.h>
+
+struct cmux_clk {
+ struct clk_hw hw;
+ void __iomem *reg;
+ u32 flags;
+};
+
+#define PLL_KILL BIT(31)
+#define CLKSEL_SHIFT 27
+#define CLKSEL_ADJUST BIT(0)
+#define to_cmux_clk(p) container_of(p, struct cmux_clk, hw)
+
+static void __iomem *base;
+static unsigned int clocks_per_pll;
+
+static int cmux_set_parent(struct clk_hw *hw, u8 idx)
+{
+ struct cmux_clk *clk = to_cmux_clk(hw);
+ u32 clksel;
+
+ clksel = ((idx / clocks_per_pll) << 2) + idx % clocks_per_pll;
+ if (clk->flags & CLKSEL_ADJUST)
+ clksel += 8;
+ clksel = (clksel & 0xf) << CLKSEL_SHIFT;
+ iowrite32be(clksel, clk->reg);
+
+ return 0;
+}
+
+static u8 cmux_get_parent(struct clk_hw *hw)
+{
+ struct cmux_clk *clk = to_cmux_clk(hw);
+ u32 clksel;
+
+ clksel = ioread32be(clk->reg);
+ clksel = (clksel >> CLKSEL_SHIFT) & 0xf;
+ if (clk->flags & CLKSEL_ADJUST)
+ clksel -= 8;
+ clksel = (clksel >> 2) * clocks_per_pll + clksel % 4;
+
+ return clksel;
+}
+
+const struct clk_ops cmux_ops = {
+ .get_parent = cmux_get_parent,
+ .set_parent = cmux_set_parent,
+};
+
+static void __init core_mux_init(struct device_node *np)
+{
+ struct clk *clk;
+ struct clk_init_data init;
+ struct cmux_clk *cmux_clk;
+ struct device_node *node;
+ int rc, count, i;
+ u32 offset;
+ const char *clk_name;
+ const char **parent_names;
+
+ rc = of_property_read_u32(np, "reg", &offset);
+ if (rc) {
+ pr_err("%s: could not get reg property\n", np->name);
+ return;
+ }
+
+ /* get the input clock source count */
+ count = of_property_count_strings(np, "clock-names");
+ if (count < 0) {
+ pr_err("%s: get clock count error\n", np->name);
+ return;
+ }
+ parent_names = kzalloc((sizeof(char *) * count), GFP_KERNEL);
+ if (!parent_names) {
+ pr_err("%s: could not allocate parent_names\n", __func__);
+ return;
+ }
+
+ for (i = 0; i < count; i++)
+ parent_names[i] = of_clk_get_parent_name(np, i);
+
+ cmux_clk = kzalloc(sizeof(struct cmux_clk), GFP_KERNEL);
+ if (!cmux_clk) {
+ pr_err("%s: could not allocate cmux_clk\n", __func__);
+ goto err_name;
+ }
+ cmux_clk->reg = base + offset;
+
+ node = of_find_compatible_node(NULL, NULL, "fsl,p4080-clockgen");
+ if (node && (offset >= 0x80))
+ cmux_clk->flags = CLKSEL_ADJUST;
+
+ rc = of_property_read_string_index(np, "clock-output-names",
+ 0, &clk_name);
+ if (rc) {
+ pr_err("%s: read clock names error\n", np->name);
+ goto err_clk;
+ }
+
+ init.name = clk_name;
+ init.ops = &cmux_ops;
+ init.parent_names = parent_names;
+ init.num_parents = count;
+ init.flags = 0;
+ cmux_clk->hw.init = &init;
+
+ clk = clk_register(NULL, &cmux_clk->hw);
+ if (IS_ERR(clk)) {
+ pr_err("%s: could not register clock\n", clk_name);
+ goto err_clk;
+ }
+
+ rc = of_clk_add_provider(np, of_clk_src_simple_get, clk);
+ if (rc) {
+ pr_err("Could not register clock provider for node:%s\n",
+ np->name);
+ goto err_clk;
+ }
+ goto err_name;
+
+err_clk:
+ kfree(cmux_clk);
+err_name:
+ /* free *_names because they are reallocated when registered */
+ kfree(parent_names);
+}
+
+static void __init core_pll_init(struct device_node *np)
+{
+ u32 offset, mult;
+ int i, rc, count;
+ const char *clk_name, *parent_name;
+ struct clk_onecell_data *onecell_data;
+ struct clk **subclks;
+
+ rc = of_property_read_u32(np, "reg", &offset);
+ if (rc) {
+ pr_err("%s: could not get reg property\n", np->name);
+ return;
+ }
+
+ /* get the multiple of PLL */
+ mult = ioread32be(base + offset);
+
+ /* check if this PLL is disabled */
+ if (mult & PLL_KILL) {
+ pr_debug("PLL:%s is disabled\n", np->name);
+ return;
+ }
+ mult = (mult >> 1) & 0x3f;
+
+ parent_name = of_clk_get_parent_name(np, 0);
+ if (!parent_name) {
+ pr_err("PLL: %s must have a parent\n", np->name);
+ return;
+ }
+
+ count = of_property_count_strings(np, "clock-output-names");
+ if (count < 0 || count > 4) {
+ pr_err("%s: clock is not supported\n", np->name);
+ return;
+ }
+
+ /* output clock number per PLL */
+ clocks_per_pll = count;
+
+ subclks = kzalloc(sizeof(struct clk *) * count, GFP_KERNEL);
+ if (!subclks) {
+ pr_err("%s: could not allocate subclks\n", __func__);
+ return;
+ }
+
+ onecell_data = kzalloc(sizeof(struct clk_onecell_data), GFP_KERNEL);
+ if (!onecell_data) {
+ pr_err("%s: could not allocate onecell_data\n", __func__);
+ goto err_clks;
+ }
+
+ for (i = 0; i < count; i++) {
+ rc = of_property_read_string_index(np, "clock-output-names",
+ i, &clk_name);
+ if (rc) {
+ pr_err("%s: could not get clock names\n", np->name);
+ goto err_cell;
+ }
+
+ /*
+ * when count == 4, there are 4 output clocks:
+ * /1, /2, /3, /4 respectively
+ * when count < 4, there are at least 2 output clocks:
+ * /1, /2, (/4, if count == 3) respectively.
+ */
+ if (count == 4)
+ subclks[i] = clk_register_fixed_factor(NULL, clk_name,
+ parent_name, 0, mult, 1 + i);
+ else
+
+ subclks[i] = clk_register_fixed_factor(NULL, clk_name,
+ parent_name, 0, mult, 1 << i);
+
+ if (IS_ERR(subclks[i])) {
+ pr_err("%s: could not register clock\n", clk_name);
+ goto err_cell;
+ }
+ }
+
+ onecell_data->clks = subclks;
+ onecell_data->clk_num = count;
+
+ rc = of_clk_add_provider(np, of_clk_src_onecell_get, onecell_data);
+ if (rc) {
+ pr_err("Could not register clk provider for node:%s\n",
+ np->name);
+ goto err_cell;
+ }
+
+ return;
+err_cell:
+ kfree(onecell_data);
+err_clks:
+ kfree(subclks);
+}
+
+static const struct of_device_id clk_match[] __initconst = {
+ { .compatible = "fixed-clock", .data = of_fixed_clk_setup, },
+ { .compatible = "fsl,core-pll-clock", .data = core_pll_init, },
+ { .compatible = "fsl,core-mux-clock", .data = core_mux_init, },
+ {}
+};
+
+static int __init ppc_corenet_clk_probe(struct platform_device *pdev)
+{
+ struct device_node *np;
+
+ np = pdev->dev.of_node;
+ base = of_iomap(np, 0);
+ if (!base) {
+ dev_err(&pdev->dev, "iomap error\n");
+ return -ENOMEM;
+ }
+ of_clk_init(clk_match);
+
+ return 0;
+}
+
+static const struct of_device_id ppc_clk_ids[] __initconst = {
+ { .compatible = "fsl,qoriq-clockgen-1.0", },
+ { .compatible = "fsl,qoriq-clockgen-2", },
+ {}
+};
+
+static struct platform_driver ppc_corenet_clk_driver = {
+ .driver = {
+ .name = "ppc_corenet_clock",
+ .owner = THIS_MODULE,
+ .of_match_table = ppc_clk_ids,
+ },
+ .probe = ppc_corenet_clk_probe,
+};
+
+static int __init ppc_corenet_clk_init(void)
+{
+ return platform_driver_register(&ppc_corenet_clk_driver);
+}
+subsys_initcall(ppc_corenet_clk_init);
--
1.8.0
More information about the devicetree-discuss
mailing list