cregit-Linux how code gets into the kernel

Release 4.7 drivers/clk/renesas/clk-r8a7740.c

/*
 * r8a7740 Core CPG Clocks
 *
 * Copyright (C) 2014  Ulrich Hecht
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; version 2 of the License.
 */

#include <linux/clk-provider.h>
#include <linux/clk/renesas.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/spinlock.h>


struct r8a7740_cpg {
	
struct clk_onecell_data data;
	
spinlock_t lock;
	
void __iomem *reg;
};


#define CPG_FRQCRA	0x00

#define CPG_FRQCRB	0x04

#define CPG_PLLC2CR	0x2c

#define CPG_USBCKCR	0x8c

#define CPG_FRQCRC	0xe0


#define CLK_ENABLE_ON_INIT BIT(0)


struct div4_clk {
	
const char *name;
	
unsigned int reg;
	
unsigned int shift;
	
int flags;
};


static struct div4_clk div4_clks[] = {
	{ "i", CPG_FRQCRA, 20, CLK_ENABLE_ON_INIT },
	{ "zg", CPG_FRQCRA, 16, CLK_ENABLE_ON_INIT },
	{ "b", CPG_FRQCRA,  8, CLK_ENABLE_ON_INIT },
	{ "m1", CPG_FRQCRA,  4, CLK_ENABLE_ON_INIT },
	{ "hp", CPG_FRQCRB,  4, 0 },
	{ "hpp", CPG_FRQCRC, 20, 0 },
	{ "usbp", CPG_FRQCRC, 16, 0 },
	{ "s", CPG_FRQCRC, 12, 0 },
	{ "zb", CPG_FRQCRC,  8, 0 },
	{ "m3", CPG_FRQCRC,  4, 0 },
	{ "cp", CPG_FRQCRC,  0, 0 },
	{ NULL, 0, 0, 0 },
};


static const struct clk_div_table div4_div_table[] = {
	{ 0, 2 }, { 1, 3 }, { 2, 4 }, { 3, 6 }, { 4, 8 }, { 5, 12 },
	{ 6, 16 }, { 7, 18 }, { 8, 24 }, { 9, 32 }, { 10, 36 }, { 11, 48 },
	{ 13, 72 }, { 14, 96 }, { 0, 0 }
};


static u32 cpg_mode __initdata;


static struct clk * __init r8a7740_cpg_register_clock(struct device_node *np, struct r8a7740_cpg *cpg, const char *name) { const struct clk_div_table *table = NULL; const char *parent_name; unsigned int shift, reg; unsigned int mult = 1; unsigned int div = 1; if (!strcmp(name, "r")) { switch (cpg_mode & (BIT(2) | BIT(1))) { case BIT(1) | BIT(2): /* extal1 */ parent_name = of_clk_get_parent_name(np, 0); div = 2048; break; case BIT(2): /* extal1 */ parent_name = of_clk_get_parent_name(np, 0); div = 1024; break; default: /* extalr */ parent_name = of_clk_get_parent_name(np, 2); break; } } else if (!strcmp(name, "system")) { parent_name = of_clk_get_parent_name(np, 0); if (cpg_mode & BIT(1)) div = 2; } else if (!strcmp(name, "pllc0")) { /* PLLC0/1 are configurable multiplier clocks. Register them as * fixed factor clocks for now as there's no generic multiplier * clock implementation and we currently have no need to change * the multiplier value. */ u32 value = clk_readl(cpg->reg + CPG_FRQCRC); parent_name = "system"; mult = ((value >> 24) & 0x7f) + 1; } else if (!strcmp(name, "pllc1")) { u32 value = clk_readl(cpg->reg + CPG_FRQCRA); parent_name = "system"; mult = ((value >> 24) & 0x7f) + 1; div = 2; } else if (!strcmp(name, "pllc2")) { u32 value = clk_readl(cpg->reg + CPG_PLLC2CR); parent_name = "system"; mult = ((value >> 24) & 0x3f) + 1; } else if (!strcmp(name, "usb24s")) { u32 value = clk_readl(cpg->reg + CPG_USBCKCR); if (value & BIT(7)) /* extal2 */ parent_name = of_clk_get_parent_name(np, 1); else parent_name = "system"; if (!(value & BIT(6))) div = 2; } else { struct div4_clk *c; for (c = div4_clks; c->name; c++) { if (!strcmp(name, c->name)) { parent_name = "pllc1"; table = div4_div_table; reg = c->reg; shift = c->shift; break; } } if (!c->name) return ERR_PTR(-EINVAL); } if (!table) { return clk_register_fixed_factor(NULL, name, parent_name, 0, mult, div); } else { return clk_register_divider_table(NULL, name, parent_name, 0, cpg->reg + reg, shift, 4, 0, table, &cpg->lock); } }

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ulrich hechtulrich hecht507100.00%1100.00%
Total507100.00%1100.00%


static void __init r8a7740_cpg_clocks_init(struct device_node *np) { struct r8a7740_cpg *cpg; struct clk **clks; unsigned int i; int num_clks; if (of_property_read_u32(np, "renesas,mode", &cpg_mode)) pr_warn("%s: missing renesas,mode property\n", __func__); num_clks = of_property_count_strings(np, "clock-output-names"); if (num_clks < 0) { pr_err("%s: failed to count clocks\n", __func__); return; } cpg = kzalloc(sizeof(*cpg), GFP_KERNEL); clks = kzalloc(num_clks * sizeof(*clks), GFP_KERNEL); if (cpg == NULL || clks == NULL) { /* We're leaking memory on purpose, there's no point in cleaning * up as the system won't boot anyway. */ return; } spin_lock_init(&cpg->lock); cpg->data.clks = clks; cpg->data.clk_num = num_clks; cpg->reg = of_iomap(np, 0); if (WARN_ON(cpg->reg == NULL)) return; for (i = 0; i < num_clks; ++i) { const char *name; struct clk *clk; of_property_read_string_index(np, "clock-output-names", i, &name); clk = r8a7740_cpg_register_clock(np, cpg, name); if (IS_ERR(clk)) pr_err("%s: failed to register %s %s clock (%ld)\n", __func__, np->name, name, PTR_ERR(clk)); else cpg->data.clks[i] = clk; } of_clk_add_provider(np, of_clk_src_onecell_get, &cpg->data); }

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ulrich hechtulrich hecht260100.00%1100.00%
Total260100.00%1100.00%

CLK_OF_DECLARE(r8a7740_cpg_clks, "renesas,r8a7740-cpg-clocks", r8a7740_cpg_clocks_init);

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ulrich hechtulrich hecht109199.63%133.33%
geert uytterhoevengeert uytterhoeven30.27%133.33%
simon hormansimon horman10.09%133.33%
Total1095100.00%3100.00%
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