diff options
Diffstat (limited to 'drivers/clk/shmobile/clk-r8a7779.c')
| -rw-r--r-- | drivers/clk/shmobile/clk-r8a7779.c | 180 |
1 files changed, 180 insertions, 0 deletions
diff --git a/drivers/clk/shmobile/clk-r8a7779.c b/drivers/clk/shmobile/clk-r8a7779.c new file mode 100644 index 000000000..652ecacb6 --- /dev/null +++ b/drivers/clk/shmobile/clk-r8a7779.c @@ -0,0 +1,180 @@ +/* + * r8a7779 Core CPG Clocks + * + * Copyright (C) 2013, 2014 Horms Solutions Ltd. + * + * Contact: Simon Horman <horms@verge.net.au> + * + * 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> + +#include <dt-bindings/clock/r8a7779-clock.h> + +#define CPG_NUM_CLOCKS (R8A7779_CLK_OUT + 1) + +struct r8a7779_cpg { + struct clk_onecell_data data; + spinlock_t lock; + void __iomem *reg; +}; + +/* ----------------------------------------------------------------------------- + * CPG Clock Data + */ + +/* + * MD1 = 1 MD1 = 0 + * (PLLA = 1500) (PLLA = 1600) + * (MHz) (MHz) + *------------------------------------------------+-------------------- + * clkz 1000 (2/3) 800 (1/2) + * clkzs 250 (1/6) 200 (1/8) + * clki 750 (1/2) 800 (1/2) + * clks 250 (1/6) 200 (1/8) + * clks1 125 (1/12) 100 (1/16) + * clks3 187.5 (1/8) 200 (1/8) + * clks4 93.7 (1/16) 100 (1/16) + * clkp 62.5 (1/24) 50 (1/32) + * clkg 62.5 (1/24) 66.6 (1/24) + * clkb, CLKOUT + * (MD2 = 0) 62.5 (1/24) 66.6 (1/24) + * (MD2 = 1) 41.6 (1/36) 50 (1/32) + */ + +#define CPG_CLK_CONFIG_INDEX(md) (((md) & (BIT(2)|BIT(1))) >> 1) + +struct cpg_clk_config { + unsigned int z_mult; + unsigned int z_div; + unsigned int zs_and_s_div; + unsigned int s1_div; + unsigned int p_div; + unsigned int b_and_out_div; +}; + +static const struct cpg_clk_config cpg_clk_configs[4] __initconst = { + { 1, 2, 8, 16, 32, 24 }, + { 2, 3, 6, 12, 24, 24 }, + { 1, 2, 8, 16, 32, 32 }, + { 2, 3, 6, 12, 24, 36 }, +}; + +/* + * MD PLLA Ratio + * 12 11 + *------------------------ + * 0 0 x42 + * 0 1 x48 + * 1 0 x56 + * 1 1 x64 + */ + +#define CPG_PLLA_MULT_INDEX(md) (((md) & (BIT(12)|BIT(11))) >> 11) + +static const unsigned int cpg_plla_mult[4] __initconst = { 42, 48, 56, 64 }; + +/* ----------------------------------------------------------------------------- + * Initialization + */ + +static u32 cpg_mode __initdata; + +static struct clk * __init +r8a7779_cpg_register_clock(struct device_node *np, struct r8a7779_cpg *cpg, + const struct cpg_clk_config *config, + unsigned int plla_mult, const char *name) +{ + const char *parent_name = "plla"; + unsigned int mult = 1; + unsigned int div = 1; + + if (!strcmp(name, "plla")) { + parent_name = of_clk_get_parent_name(np, 0); + mult = plla_mult; + } else if (!strcmp(name, "z")) { + div = config->z_div; + mult = config->z_mult; + } else if (!strcmp(name, "zs") || !strcmp(name, "s")) { + div = config->zs_and_s_div; + } else if (!strcmp(name, "s1")) { + div = config->s1_div; + } else if (!strcmp(name, "p")) { + div = config->p_div; + } else if (!strcmp(name, "b") || !strcmp(name, "out")) { + div = config->b_and_out_div; + } else { + return ERR_PTR(-EINVAL); + } + + return clk_register_fixed_factor(NULL, name, parent_name, 0, mult, div); +} + +static void __init r8a7779_cpg_clocks_init(struct device_node *np) +{ + const struct cpg_clk_config *config; + struct r8a7779_cpg *cpg; + struct clk **clks; + unsigned int i, plla_mult; + int num_clks; + + 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(CPG_NUM_CLOCKS * 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; + + config = &cpg_clk_configs[CPG_CLK_CONFIG_INDEX(cpg_mode)]; + plla_mult = cpg_plla_mult[CPG_PLLA_MULT_INDEX(cpg_mode)]; + + 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 = r8a7779_cpg_register_clock(np, cpg, config, + plla_mult, 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(r8a7779_cpg_clks, "renesas,r8a7779-cpg-clocks", + r8a7779_cpg_clocks_init); + +void __init r8a7779_clocks_init(u32 mode) +{ + cpg_mode = mode; + + of_clk_init(NULL); +} |