// SPDX-License-Identifier: GPL-2.0
/*
* r8a7740 Core CPG Clocks
*
* Copyright (C) 2014 Ulrich Hecht
*/
#include <linux/clk-provider.h>
#include <linux/clk/renesas.h>
#include <linux/init.h>
#include <linux/io.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;
};
#define CPG_FRQCRA 0x00
#define CPG_FRQCRB 0x04
#define CPG_PLLC2CR 0x2c
#define CPG_USBCKCR 0x8c
#define CPG_FRQCRC 0xe0
struct div4_clk {
const char *name;
unsigned int reg;
unsigned int shift;
};
static struct div4_clk div4_clks[] = {
{ "i", CPG_FRQCRA, 20 },
{ "zg", CPG_FRQCRA, 16 },
{ "b", CPG_FRQCRA, 8 },
{ "m1", CPG_FRQCRA, 4 },
{ "hp", CPG_FRQCRB, 4 },
{ "hpp", CPG_FRQCRC, 20 },
{ "usbp", CPG_FRQCRC, 16 },
{ "s", CPG_FRQCRC, 12 },
{ "zb", CPG_FRQCRC, 8 },
{ "m3", CPG_FRQCRC, 4 },
{ "cp", CPG_FRQCRC, 0 },
{ NULL, 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,
void __iomem *base, 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 = readl(base + CPG_FRQCRC);
parent_name = "system";
mult = ((value >> 24) & 0x7f) + 1;
} else if (!strcmp(name, "pllc1")) {
u32 value = readl(base + CPG_FRQCRA);
parent_name = "system";
mult = ((value >> 24) & 0x7f) + 1;
div = 2;
} else if (!strcmp(name, "pllc2")) {
u32 value = readl(base + CPG_PLLC2CR);
parent_name = "system";
mult = ((value >> 24) & 0x3f) + 1;
} else if (!strcmp(name, "usb24s")) {
u32 value = readl(base + 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,
base + reg, shift, 4, 0,
table, &cpg->lock);
}
}
static void __init r8a7740_cpg_clocks_init(struct device_node *np)
{
struct r8a7740_cpg *cpg;
void __iomem *base;
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 = kcalloc(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;
base = of_iomap(np, 0);
if (WARN_ON(base == 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, base, name);
if (IS_ERR(clk))
pr_err("%s: failed to register %pOFn %s clock (%ld)\n",
__func__, np, name, PTR_ERR(clk));
else
cpg->data.clks[i] = clk;
}
of_clk_add_provider(np, of_clk_src_onecell_get, &cpg->data);
}
CLK_OF_DECLARE(r8a7740_cpg_clks, "renesas,r8a7740-cpg-clocks",
r8a7740_cpg_clocks_init);
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