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Release 4.7 drivers/clk/clk-tango4.c

Directory: drivers/clk
#include <linux/kernel.h>
#include <linux/clk-provider.h>
#include <linux/of_address.h>
#include <linux/init.h>
#include <linux/io.h>


#define CLK_COUNT 4 
/* cpu_clk, sys_clk, usb_clk, sdio_clk */

static struct clk *clks[CLK_COUNT];

static struct clk_onecell_data clk_data = { clks, CLK_COUNT };


#define SYSCLK_DIV	0x20

#define CPUCLK_DIV	0x24

#define DIV_BYPASS	BIT(23)

/*** CLKGEN_PLL ***/

#define extract_pll_n(val)	((val >>  0) & ((1u << 7) - 1))

#define extract_pll_k(val)	((val >> 13) & ((1u << 3) - 1))

#define extract_pll_m(val)	((val >> 16) & ((1u << 3) - 1))

#define extract_pll_isel(val)	((val >> 24) & ((1u << 3) - 1))


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(base + idx * 8); mul = extract_pll_n(val) + 1; div = (extract_pll_m(val) + 1) << extract_pll_k(val); clk_register_fixed_factor(NULL, name, parent, 0, mul, div); if (extract_pll_isel(val) != 1) panic("%s: input not set to XTAL_IN\n", name); }

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static void __init make_cd(int idx, void __iomem *base) { char name[8]; u32 val, mul, div; sprintf(name, "cd%d", idx); val = readl(base + idx * 8); mul = 1 << 27; div = (2 << 27) + val; clk_register_fixed_factor(NULL, name, "pll2", 0, mul, div); if (val > 0xf0000000) panic("%s: unsupported divider %x\n", name, val); }

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static void __init tango4_clkgen_setup(struct device_node *np) { struct clk **pp = clk_data.clks; 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->name); if (readl(base + CPUCLK_DIV) & DIV_BYPASS) panic("%s: unsupported cpuclk setup\n", np->name); if (readl(base + SYSCLK_DIV) & DIV_BYPASS) panic("%s: unsupported sysclk setup\n", np->name); writel(0x100, base + CPUCLK_DIV); /* disable frequency ramping */ make_pll(0, parent, base); make_pll(1, parent, base); make_pll(2, parent, base); make_cd(2, base + 0x80); make_cd(6, base + 0x80); pp[0] = clk_register_divider(NULL, "cpu_clk", "pll0", 0, base + CPUCLK_DIV, 8, 8, CLK_DIVIDER_ONE_BASED, NULL); pp[1] = clk_register_fixed_factor(NULL, "sys_clk", "pll1", 0, 1, 4); pp[2] = clk_register_fixed_factor(NULL, "usb_clk", "cd2", 0, 1, 2); pp[3] = clk_register_fixed_factor(NULL, "sdio_clk", "cd6", 0, 1, 2); if (IS_ERR(pp[0]) || IS_ERR(pp[1]) || IS_ERR(pp[2]) || IS_ERR(pp[3])) panic("%s: clk registration failed\n", np->name); if (of_clk_add_provider(np, of_clk_src_onecell_get, &clk_data)) panic("%s: clk provider registration failed\n", np->name); }

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CLK_OF_DECLARE(tango4_clkgen, "sigma,tango4-clkgen", tango4_clkgen_setup);

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Directory: drivers/clk
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