diff options
| -rw-r--r-- | Documentation/devicetree/bindings/clock/tango4-clock.txt | 23 | ||||
| -rw-r--r-- | drivers/clk/Makefile | 1 | ||||
| -rw-r--r-- | drivers/clk/clk-tango4.c | 61 |
3 files changed, 85 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/clock/tango4-clock.txt b/Documentation/devicetree/bindings/clock/tango4-clock.txt new file mode 100644 index 000000000000..19c580a7bda2 --- /dev/null +++ b/Documentation/devicetree/bindings/clock/tango4-clock.txt @@ -0,0 +1,23 @@ +* Sigma Designs Tango4 Clock Generator + +The Tango4 clock generator outputs cpu_clk and sys_clk (the latter is used +for RAM and various peripheral devices). The clock binding described here +is applicable to all Tango4 SoCs. + +Required Properties: + +- compatible: should be "sigma,tango4-clkgen". +- reg: physical base address of the device and length of memory mapped region. +- clocks: phandle of the input clock (crystal oscillator). +- clock-output-names: should be "cpuclk" and "sysclk". +- #clock-cells: should be set to 1. + +Example: + + clkgen: clkgen@10000 { + compatible = "sigma,tango4-clkgen"; + reg = <0x10000 0x40>; + clocks = <&xtal>; + clock-output-names = "cpuclk", "sysclk"; + #clock-cells = <1>; + }; diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile index 820714c72d36..f4165bb9a270 100644 --- a/drivers/clk/Makefile +++ b/drivers/clk/Makefile @@ -42,6 +42,7 @@ obj-$(CONFIG_COMMON_CLK_SI514) += clk-si514.o obj-$(CONFIG_COMMON_CLK_SI570) += clk-si570.o obj-$(CONFIG_COMMON_CLK_CDCE925) += clk-cdce925.o obj-$(CONFIG_ARCH_STM32) += clk-stm32f4.o +obj-$(CONFIG_ARCH_TANGOX) += clk-tango4.o obj-$(CONFIG_CLK_TWL6040) += clk-twl6040.o obj-$(CONFIG_ARCH_U300) += clk-u300.o obj-$(CONFIG_ARCH_VT8500) += clk-vt8500.o diff --git a/drivers/clk/clk-tango4.c b/drivers/clk/clk-tango4.c new file mode 100644 index 000000000000..004ab7dfcfe3 --- /dev/null +++ b/drivers/clk/clk-tango4.c @@ -0,0 +1,61 @@ +#include <linux/kernel.h> +#include <linux/clk-provider.h> +#include <linux/of_address.h> +#include <linux/init.h> +#include <linux/io.h> + +static struct clk *out[2]; +static struct clk_onecell_data clk_data = { out, 2 }; + +#define SYSCLK_CTRL 0x20 +#define CPUCLK_CTRL 0x24 +#define LEGACY_DIV 0x3c + +#define PLL_N(val) (((val) >> 0) & 0x7f) +#define PLL_K(val) (((val) >> 13) & 0x7) +#define PLL_M(val) (((val) >> 16) & 0x7) +#define DIV_INDEX(val) (((val) >> 8) & 0xf) + +static void __init make_pll(int idx, const char *parent, void __iomem *base) +{ + char name[8]; + u32 val, mul, div; + + sprintf(name, "pll%d", idx); + val = readl_relaxed(base + idx*8); + mul = PLL_N(val) + 1; + div = (PLL_M(val) + 1) << PLL_K(val); + clk_register_fixed_factor(NULL, name, parent, 0, mul, div); +} + +static int __init get_div(void __iomem *base) +{ + u8 sysclk_tab[16] = { 2, 4, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4 }; + int idx = DIV_INDEX(readl_relaxed(base + LEGACY_DIV)); + + return sysclk_tab[idx]; +} + +static void __init tango4_clkgen_setup(struct device_node *np) +{ + int div, ret; + void __iomem *base = of_iomap(np, 0); + const char *parent = of_clk_get_parent_name(np, 0); + + if (!base) + panic("%s: invalid address\n", np->full_name); + + make_pll(0, parent, base); + make_pll(1, parent, base); + + out[0] = clk_register_divider(NULL, "cpuclk", "pll0", 0, + base + CPUCLK_CTRL, 8, 8, CLK_DIVIDER_ONE_BASED, NULL); + + div = readl_relaxed(base + SYSCLK_CTRL) & BIT(23) ? get_div(base) : 4; + out[1] = clk_register_fixed_factor(NULL, "sysclk", "pll1", 0, 1, div); + + ret = of_clk_add_provider(np, of_clk_src_onecell_get, &clk_data); + if (IS_ERR(out[0]) || IS_ERR(out[1]) || ret < 0) + panic("%s: clk registration failed\n", np->full_name); +} +CLK_OF_DECLARE(tango4_clkgen, "sigma,tango4-clkgen", tango4_clkgen_setup); |