Stoney SoC provides oscout clock. This clock can support 25Mhz and
48Mhz of frequency.
The clock is available for general system use.
Signed-off-by: Akshu Agrawal <akshu.agrawal@xxxxxxx>
---
v2: config change, added SPDX tag and used clk_hw_register_.
v3: Fix kbuild warning for checking of NULL pointer
v4: unregister clk_hw in driver remove, add .suppress_bind_attrs
drivers/clk/x86/Makefile | 3 +-
drivers/clk/x86/clk-st.c | 85 ++++++++++++++++++++++++++++++++++++
include/linux/platform_data/clk-st.h | 17 ++++++++
3 files changed, 104 insertions(+), 1 deletion(-)
create mode 100644 drivers/clk/x86/clk-st.c
create mode 100644 include/linux/platform_data/clk-st.h
diff --git a/drivers/clk/x86/Makefile b/drivers/clk/x86/Makefile
index 1367afb..00303bc 100644
--- a/drivers/clk/x86/Makefile
+++ b/drivers/clk/x86/Makefile
@@ -1,3 +1,4 @@
+obj-$(CONFIG_PMC_ATOM) += clk-pmc-atom.o
+obj-$(CONFIG_X86_AMD_PLATFORM_DEVICE) += clk-st.o
clk-x86-lpss-objs := clk-lpt.o
obj-$(CONFIG_X86_INTEL_LPSS) += clk-x86-lpss.o
-obj-$(CONFIG_PMC_ATOM) += clk-pmc-atom.o
diff --git a/drivers/clk/x86/clk-st.c b/drivers/clk/x86/clk-st.c
new file mode 100644
index 0000000..8a7795c
--- /dev/null
+++ b/drivers/clk/x86/clk-st.c
@@ -0,0 +1,85 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * clock framework for AMD Stoney based clocks
+ *
+ * Copyright 2018 Advanced Micro Devices, Inc.
+ */
+
+#include <linux/clk.h>
+#include <linux/clkdev.h>
+#include <linux/clk-provider.h>
+#include <linux/platform_data/clk-st.h>
+#include <linux/platform_device.h>
+
+/* Clock Driving Strength 2 register */
+#define CLKDRVSTR2 0x28
+/* Clock Control 1 register */
+#define MISCCLKCNTL1 0x40
+/* Auxiliary clock1 enable bit */
+#define OSCCLKENB 2
+/* 25Mhz auxiliary output clock freq bit */
+#define OSCOUT1CLK25MHZ 16
+
+#define ST_CLK_48M 0
+#define ST_CLK_25M 1
+#define ST_CLK_MUX 2
+#define ST_CLK_GATE 3
+#define ST_MAX_CLKS 4
+
+static const char * const clk_oscout1_parents[] = { "clk48MHz", "clk25MHz" };
+
+static int st_clk_probe(struct platform_device *pdev)
+{
+ struct st_clk_data *st_data;
+ struct clk_hw **hws;
+
+ st_data = dev_get_platdata(&pdev->dev);
+ if (!st_data || !st_data->base)
+ return -EINVAL;
+
+ hws = devm_kzalloc(&pdev->dev, sizeof(*hws) * ST_MAX_CLKS, GFP_KERNEL);
+ if (!hws)
+ return -ENOMEM;
+
+ hws[ST_CLK_48M] = clk_hw_register_fixed_rate(NULL, "clk48MHz", NULL, 0,
+ 48000000);
+ hws[ST_CLK_25M] = clk_hw_register_fixed_rate(NULL, "clk25MHz", NULL, 0,
+ 25000000);
+
+ hws[ST_CLK_MUX] = clk_hw_register_mux(NULL, "oscout1_mux",
+ clk_oscout1_parents, ARRAY_SIZE(clk_oscout1_parents),
+ 0, st_data->base + CLKDRVSTR2, OSCOUT1CLK25MHZ, 3, 0, NULL);
+
+ clk_set_parent(hws[ST_CLK_MUX]->clk, hws[ST_CLK_25M]->clk);
+
+ hws[ST_CLK_GATE] = clk_hw_register_gate(NULL, "oscout1", "oscout1_mux",
+ 0, st_data->base + MISCCLKCNTL1, OSCCLKENB,
+ CLK_GATE_SET_TO_DISABLE, NULL);
+
+ clk_hw_register_clkdev(hws[ST_CLK_GATE], "oscout1", NULL);
+
+ platform_set_drvdata(pdev, hws);
+ return 0;
+}
+
+static int st_clk_remove(struct platform_device *pdev)
+{
+ struct clk_hw **hws;
+ int i;
+
+ hws = platform_get_drvdata(pdev);
+
+ for (i = 0; i < ST_MAX_CLKS; i++)
+ clk_hw_unregister(hws[i]);
+ return 0;
+}
+
+static struct platform_driver st_clk_driver = {
+ .driver = {
+ .name = "clk-st",
+ .suppress_bind_attrs = true,
+ },
+ .probe = st_clk_probe,
+ .remove = st_clk_remove,
+};
+builtin_platform_driver(st_clk_driver);
diff --git a/include/linux/platform_data/clk-st.h b/include/linux/platform_data/clk-st.h
new file mode 100644
index 0000000..188184d
--- /dev/null
+++ b/include/linux/platform_data/clk-st.h
@@ -0,0 +1,17 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * clock framework for AMD Stoney based clock
+ *
+ * Copyright 2018 Advanced Micro Devices, Inc.
+ */
+
+#ifndef __CLK_ST_H
+#define __CLK_ST_H
+
+#include <linux/compiler.h>
+
+struct st_clk_data {
+ void __iomem *base;
+};
+
+#endif /* __CLK_ST_H */
--
1.9.1
--
To unsubscribe from this list: send the line "unsubscribe linux-acpi" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
