diff options
Diffstat (limited to 'drivers/clk/sunxi/clk-sunxi.c')
| -rw-r--r-- | drivers/clk/sunxi/clk-sunxi.c | 469 |
1 files changed, 469 insertions, 0 deletions
diff --git a/drivers/clk/sunxi/clk-sunxi.c b/drivers/clk/sunxi/clk-sunxi.c new file mode 100644 index 000000000000..8492ad1d5360 --- /dev/null +++ b/drivers/clk/sunxi/clk-sunxi.c @@ -0,0 +1,469 @@ +/* + * Copyright 2013 Emilio López + * + * Emilio López <emilio@elopez.com.ar> + * + * 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; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/clk-provider.h> +#include <linux/clkdev.h> +#include <linux/clk/sunxi.h> +#include <linux/of.h> +#include <linux/of_address.h> + +#include "clk-factors.h" + +static DEFINE_SPINLOCK(clk_lock); + +/** + * sunxi_osc_clk_setup() - Setup function for gatable oscillator + */ + +#define SUNXI_OSC24M_GATE 0 + +static void __init sunxi_osc_clk_setup(struct device_node *node) +{ + struct clk *clk; + struct clk_fixed_rate *fixed; + struct clk_gate *gate; + const char *clk_name = node->name; + u32 rate; + + /* allocate fixed-rate and gate clock structs */ + fixed = kzalloc(sizeof(struct clk_fixed_rate), GFP_KERNEL); + if (!fixed) + return; + gate = kzalloc(sizeof(struct clk_gate), GFP_KERNEL); + if (!gate) { + kfree(fixed); + return; + } + + if (of_property_read_u32(node, "clock-frequency", &rate)) + return; + + /* set up gate and fixed rate properties */ + gate->reg = of_iomap(node, 0); + gate->bit_idx = SUNXI_OSC24M_GATE; + gate->lock = &clk_lock; + fixed->fixed_rate = rate; + + clk = clk_register_composite(NULL, clk_name, + NULL, 0, + NULL, NULL, + &fixed->hw, &clk_fixed_rate_ops, + &gate->hw, &clk_gate_ops, + CLK_IS_ROOT); + + if (clk) { + of_clk_add_provider(node, of_clk_src_simple_get, clk); + clk_register_clkdev(clk, clk_name, NULL); + } +} + + + +/** + * sunxi_get_pll1_factors() - calculates n, k, m, p factors for PLL1 + * PLL1 rate is calculated as follows + * rate = (parent_rate * n * (k + 1) >> p) / (m + 1); + * parent_rate is always 24Mhz + */ + +static void sunxi_get_pll1_factors(u32 *freq, u32 parent_rate, + u8 *n, u8 *k, u8 *m, u8 *p) +{ + u8 div; + + /* Normalize value to a 6M multiple */ + div = *freq / 6000000; + *freq = 6000000 * div; + + /* we were called to round the frequency, we can now return */ + if (n == NULL) + return; + + /* m is always zero for pll1 */ + *m = 0; + + /* k is 1 only on these cases */ + if (*freq >= 768000000 || *freq == 42000000 || *freq == 54000000) + *k = 1; + else + *k = 0; + + /* p will be 3 for divs under 10 */ + if (div < 10) + *p = 3; + + /* p will be 2 for divs between 10 - 20 and odd divs under 32 */ + else if (div < 20 || (div < 32 && (div & 1))) + *p = 2; + + /* p will be 1 for even divs under 32, divs under 40 and odd pairs + * of divs between 40-62 */ + else if (div < 40 || (div < 64 && (div & 2))) + *p = 1; + + /* any other entries have p = 0 */ + else + *p = 0; + + /* calculate a suitable n based on k and p */ + div <<= *p; + div /= (*k + 1); + *n = div / 4; +} + + + +/** + * sunxi_get_apb1_factors() - calculates m, p factors for APB1 + * APB1 rate is calculated as follows + * rate = (parent_rate >> p) / (m + 1); + */ + +static void sunxi_get_apb1_factors(u32 *freq, u32 parent_rate, + u8 *n, u8 *k, u8 *m, u8 *p) +{ + u8 calcm, calcp; + + if (parent_rate < *freq) + *freq = parent_rate; + + parent_rate = (parent_rate + (*freq - 1)) / *freq; + + /* Invalid rate! */ + if (parent_rate > 32) + return; + + if (parent_rate <= 4) + calcp = 0; + else if (parent_rate <= 8) + calcp = 1; + else if (parent_rate <= 16) + calcp = 2; + else + calcp = 3; + + calcm = (parent_rate >> calcp) - 1; + + *freq = (parent_rate >> calcp) / (calcm + 1); + + /* we were called to round the frequency, we can now return */ + if (n == NULL) + return; + + *m = calcm; + *p = calcp; +} + + + +/** + * sunxi_factors_clk_setup() - Setup function for factor clocks + */ + +struct factors_data { + struct clk_factors_config *table; + void (*getter) (u32 *rate, u32 parent_rate, u8 *n, u8 *k, u8 *m, u8 *p); +}; + +static struct clk_factors_config pll1_config = { + .nshift = 8, + .nwidth = 5, + .kshift = 4, + .kwidth = 2, + .mshift = 0, + .mwidth = 2, + .pshift = 16, + .pwidth = 2, +}; + +static struct clk_factors_config apb1_config = { + .mshift = 0, + .mwidth = 5, + .pshift = 16, + .pwidth = 2, +}; + +static const __initconst struct factors_data pll1_data = { + .table = &pll1_config, + .getter = sunxi_get_pll1_factors, +}; + +static const __initconst struct factors_data apb1_data = { + .table = &apb1_config, + .getter = sunxi_get_apb1_factors, +}; + +static void __init sunxi_factors_clk_setup(struct device_node *node, + struct factors_data *data) +{ + struct clk *clk; + const char *clk_name = node->name; + const char *parent; + void *reg; + + reg = of_iomap(node, 0); + + parent = of_clk_get_parent_name(node, 0); + + clk = clk_register_factors(NULL, clk_name, parent, 0, reg, + data->table, data->getter, &clk_lock); + + if (clk) { + of_clk_add_provider(node, of_clk_src_simple_get, clk); + clk_register_clkdev(clk, clk_name, NULL); + } +} + + + +/** + * sunxi_mux_clk_setup() - Setup function for muxes + */ + +#define SUNXI_MUX_GATE_WIDTH 2 + +struct mux_data { + u8 shift; +}; + +static const __initconst struct mux_data cpu_data = { + .shift = 16, +}; + +static const __initconst struct mux_data apb1_mux_data = { + .shift = 24, +}; + +static void __init sunxi_mux_clk_setup(struct device_node *node, + struct mux_data *data) +{ + struct clk *clk; + const char *clk_name = node->name; + const char *parents[5]; + void *reg; + int i = 0; + + reg = of_iomap(node, 0); + + while (i < 5 && (parents[i] = of_clk_get_parent_name(node, i)) != NULL) + i++; + + clk = clk_register_mux(NULL, clk_name, parents, i, 0, reg, + data->shift, SUNXI_MUX_GATE_WIDTH, + 0, &clk_lock); + + if (clk) { + of_clk_add_provider(node, of_clk_src_simple_get, clk); + clk_register_clkdev(clk, clk_name, NULL); + } +} + + + +/** + * sunxi_divider_clk_setup() - Setup function for simple divider clocks + */ + +#define SUNXI_DIVISOR_WIDTH 2 + +struct div_data { + u8 shift; + u8 pow; +}; + +static const __initconst struct div_data axi_data = { + .shift = 0, + .pow = 0, +}; + +static const __initconst struct div_data ahb_data = { + .shift = 4, + .pow = 1, +}; + +static const __initconst struct div_data apb0_data = { + .shift = 8, + .pow = 1, +}; + +static void __init sunxi_divider_clk_setup(struct device_node *node, + struct div_data *data) +{ + struct clk *clk; + const char *clk_name = node->name; + const char *clk_parent; + void *reg; + + reg = of_iomap(node, 0); + + clk_parent = of_clk_get_parent_name(node, 0); + + clk = clk_register_divider(NULL, clk_name, clk_parent, 0, + reg, data->shift, SUNXI_DIVISOR_WIDTH, + data->pow ? CLK_DIVIDER_POWER_OF_TWO : 0, + &clk_lock); + if (clk) { + of_clk_add_provider(node, of_clk_src_simple_get, clk); + clk_register_clkdev(clk, clk_name, NULL); + } +} + + + +/** + * sunxi_gates_clk_setup() - Setup function for leaf gates on clocks + */ + +#define SUNXI_GATES_MAX_SIZE 64 + +struct gates_data { + DECLARE_BITMAP(mask, SUNXI_GATES_MAX_SIZE); +}; + +static const __initconst struct gates_data axi_gates_data = { + .mask = {1}, +}; + +static const __initconst struct gates_data ahb_gates_data = { + .mask = {0x7F77FFF, 0x14FB3F}, +}; + +static const __initconst struct gates_data apb0_gates_data = { + .mask = {0x4EF}, +}; + +static const __initconst struct gates_data apb1_gates_data = { + .mask = {0xFF00F7}, +}; + +static void __init sunxi_gates_clk_setup(struct device_node *node, + struct gates_data *data) +{ + struct clk_onecell_data *clk_data; + const char *clk_parent; + const char *clk_name; + void *reg; + int qty; + int i = 0; + int j = 0; + int ignore; + + reg = of_iomap(node, 0); + + clk_parent = of_clk_get_parent_name(node, 0); + + /* Worst-case size approximation and memory allocation */ + qty = find_last_bit(data->mask, SUNXI_GATES_MAX_SIZE); + clk_data = kmalloc(sizeof(struct clk_onecell_data), GFP_KERNEL); + if (!clk_data) + return; + clk_data->clks = kzalloc((qty+1) * sizeof(struct clk *), GFP_KERNEL); + if (!clk_data->clks) { + kfree(clk_data); + return; + } + + for_each_set_bit(i, data->mask, SUNXI_GATES_MAX_SIZE) { + of_property_read_string_index(node, "clock-output-names", + j, &clk_name); + + /* No driver claims this clock, but it should remain gated */ + ignore = !strcmp("ahb_sdram", clk_name) ? CLK_IGNORE_UNUSED : 0; + + clk_data->clks[i] = clk_register_gate(NULL, clk_name, + clk_parent, ignore, + reg + 4 * (i/32), i % 32, + 0, &clk_lock); + WARN_ON(IS_ERR(clk_data->clks[i])); + + j++; + } + + /* Adjust to the real max */ + clk_data->clk_num = i; + + of_clk_add_provider(node, of_clk_src_onecell_get, clk_data); +} + +/* Matches for of_clk_init */ +static const __initconst struct of_device_id clk_match[] = { + {.compatible = "allwinner,sun4i-osc-clk", .data = sunxi_osc_clk_setup,}, + {} +}; + +/* Matches for factors clocks */ +static const __initconst struct of_device_id clk_factors_match[] = { + {.compatible = "allwinner,sun4i-pll1-clk", .data = &pll1_data,}, + {.compatible = "allwinner,sun4i-apb1-clk", .data = &apb1_data,}, + {} +}; + +/* Matches for divider clocks */ +static const __initconst struct of_device_id clk_div_match[] = { + {.compatible = "allwinner,sun4i-axi-clk", .data = &axi_data,}, + {.compatible = "allwinner,sun4i-ahb-clk", .data = &ahb_data,}, + {.compatible = "allwinner,sun4i-apb0-clk", .data = &apb0_data,}, + {} +}; + +/* Matches for mux clocks */ +static const __initconst struct of_device_id clk_mux_match[] = { + {.compatible = "allwinner,sun4i-cpu-clk", .data = &cpu_data,}, + {.compatible = "allwinner,sun4i-apb1-mux-clk", .data = &apb1_mux_data,}, + {} +}; + +/* Matches for gate clocks */ +static const __initconst struct of_device_id clk_gates_match[] = { + {.compatible = "allwinner,sun4i-axi-gates-clk", .data = &axi_gates_data,}, + {.compatible = "allwinner,sun4i-ahb-gates-clk", .data = &ahb_gates_data,}, + {.compatible = "allwinner,sun4i-apb0-gates-clk", .data = &apb0_gates_data,}, + {.compatible = "allwinner,sun4i-apb1-gates-clk", .data = &apb1_gates_data,}, + {} +}; + +static void __init of_sunxi_table_clock_setup(const struct of_device_id *clk_match, + void *function) +{ + struct device_node *np; + const struct div_data *data; + const struct of_device_id *match; + void (*setup_function)(struct device_node *, const void *) = function; + + for_each_matching_node(np, clk_match) { + match = of_match_node(clk_match, np); + data = match->data; + setup_function(np, data); + } +} + +void __init sunxi_init_clocks(void) +{ + /* Register all the simple sunxi clocks on DT */ + of_clk_init(clk_match); + + /* Register factor clocks */ + of_sunxi_table_clock_setup(clk_factors_match, sunxi_factors_clk_setup); + + /* Register divider clocks */ + of_sunxi_table_clock_setup(clk_div_match, sunxi_divider_clk_setup); + + /* Register mux clocks */ + of_sunxi_table_clock_setup(clk_mux_match, sunxi_mux_clk_setup); + + /* Register gate clocks */ + of_sunxi_table_clock_setup(clk_gates_match, sunxi_gates_clk_setup); +} |