diff options
Diffstat (limited to 'drivers/clk/shmobile/clk-r8a7740.c')
| -rw-r--r-- | drivers/clk/shmobile/clk-r8a7740.c | 199 |
1 files changed, 199 insertions, 0 deletions
diff --git a/drivers/clk/shmobile/clk-r8a7740.c b/drivers/clk/shmobile/clk-r8a7740.c new file mode 100644 index 000000000..1e2eaae21 --- /dev/null +++ b/drivers/clk/shmobile/clk-r8a7740.c @@ -0,0 +1,199 @@ +/* + * 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/clkdev.h> +#include <linux/clk/shmobile.h> +#include <linux/init.h> +#include <linux/kernel.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); + } +} + +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); +} +CLK_OF_DECLARE(r8a7740_cpg_clks, "renesas,r8a7740-cpg-clocks", + r8a7740_cpg_clocks_init); |