diff options
Diffstat (limited to 'drivers/clk/x86/clk-st.c')
-rw-r--r-- | drivers/clk/x86/clk-st.c | 77 |
1 files changed, 77 insertions, 0 deletions
diff --git a/drivers/clk/x86/clk-st.c b/drivers/clk/x86/clk-st.c new file mode 100644 index 000000000..3a0996f2d --- /dev/null +++ b/drivers/clk/x86/clk-st.c @@ -0,0 +1,77 @@ +// SPDX-License-Identifier: MIT +/* + * 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 struct clk_hw *hws[ST_MAX_CLKS]; + +static int st_clk_probe(struct platform_device *pdev) +{ + struct st_clk_data *st_data; + + st_data = dev_get_platdata(&pdev->dev); + if (!st_data || !st_data->base) + return -EINVAL; + + 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_48M]->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); + + return 0; +} + +static int st_clk_remove(struct platform_device *pdev) +{ + int i; + + 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); |