arch/sh/kernel/cpu/sh4a/clock-sh7785.c

Source file repositories/reference/linux-study-clean/arch/sh/kernel/cpu/sh4a/clock-sh7785.c

File Facts

System
Linux kernel
Corpus path
arch/sh/kernel/cpu/sh4a/clock-sh7785.c
Extension
.c
Size
5462 bytes
Lines
175
Domain
Architecture Layer
Bucket
arch/sh
Inferred role
Architecture Layer: implementation source
Status
source implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

// SPDX-License-Identifier: GPL-2.0
/*
 * arch/sh/kernel/cpu/sh4a/clock-sh7785.c
 *
 * SH7785 support for the clock framework
 *
 *  Copyright (C) 2007 - 2010  Paul Mundt
 */
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/cpufreq.h>
#include <linux/clkdev.h>
#include <asm/clock.h>
#include <asm/freq.h>
#include <cpu/sh7785.h>

/*
 * Default rate for the root input clock, reset this with clk_set_rate()
 * from the platform code.
 */
static struct clk extal_clk = {
	.rate		= 33333333,
};

static unsigned long pll_recalc(struct clk *clk)
{
	int multiplier;

	multiplier = test_mode_pin(MODE_PIN4) ? 36 : 72;

	return clk->parent->rate * multiplier;
}

static struct sh_clk_ops pll_clk_ops = {
	.recalc		= pll_recalc,
};

static struct clk pll_clk = {
	.ops		= &pll_clk_ops,
	.parent		= &extal_clk,
	.flags		= CLK_ENABLE_ON_INIT,
};

static struct clk *clks[] = {
	&extal_clk,
	&pll_clk,
};

static unsigned int div2[] = { 1, 2, 4, 6, 8, 12, 16, 18,
			       24, 32, 36, 48 };

static struct clk_div_mult_table div4_div_mult_table = {
	.divisors = div2,
	.nr_divisors = ARRAY_SIZE(div2),
};

static struct clk_div4_table div4_table = {
	.div_mult_table = &div4_div_mult_table,
};

enum { DIV4_I, DIV4_U, DIV4_SH, DIV4_B, DIV4_DDR, DIV4_GA,
	DIV4_DU, DIV4_P, DIV4_NR };

#define DIV4(_bit, _mask, _flags) \
  SH_CLK_DIV4(&pll_clk, FRQMR1, _bit, _mask, _flags)

struct clk div4_clks[DIV4_NR] = {
	[DIV4_P] = DIV4(0, 0x0f80, 0),
	[DIV4_DU] = DIV4(4, 0x0ff0, 0),
	[DIV4_GA] = DIV4(8, 0x0030, 0),
	[DIV4_DDR] = DIV4(12, 0x000c, CLK_ENABLE_ON_INIT),
	[DIV4_B] = DIV4(16, 0x0fe0, CLK_ENABLE_ON_INIT),
	[DIV4_SH] = DIV4(20, 0x000c, CLK_ENABLE_ON_INIT),
	[DIV4_U] = DIV4(24, 0x000c, CLK_ENABLE_ON_INIT),
	[DIV4_I] = DIV4(28, 0x000e, CLK_ENABLE_ON_INIT),
};

#define MSTPCR0		0xffc80030
#define MSTPCR1		0xffc80034

enum { MSTP029, MSTP028, MSTP027, MSTP026, MSTP025, MSTP024,
       MSTP021, MSTP020, MSTP017, MSTP016,
       MSTP013, MSTP012, MSTP009, MSTP008, MSTP003, MSTP002,
       MSTP119, MSTP117, MSTP105, MSTP104, MSTP100,
       MSTP_NR };

static struct clk mstp_clks[MSTP_NR] = {
	/* MSTPCR0 */

Annotation

Implementation Notes