diff options
Diffstat (limited to 'drivers/clk/loongson1/clk-loongson1b.c')
| -rw-r--r-- | drivers/clk/loongson1/clk-loongson1b.c | 122 |
1 files changed, 122 insertions, 0 deletions
diff --git a/drivers/clk/loongson1/clk-loongson1b.c b/drivers/clk/loongson1/clk-loongson1b.c new file mode 100644 index 000000000..f36a97e99 --- /dev/null +++ b/drivers/clk/loongson1/clk-loongson1b.c @@ -0,0 +1,122 @@ +/* + * Copyright (c) 2012-2016 Zhang, Keguang <keguang.zhang@gmail.com> + * + * 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. + */ + +#include <linux/clkdev.h> +#include <linux/clk-provider.h> +#include <linux/io.h> +#include <linux/err.h> + +#include <loongson1.h> +#include "clk.h" + +#define OSC (33 * 1000000) +#define DIV_APB 2 + +static DEFINE_SPINLOCK(_lock); + +static unsigned long ls1x_pll_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + u32 pll, rate; + + pll = __raw_readl(LS1X_CLK_PLL_FREQ); + rate = 12 + (pll & GENMASK(5, 0)); + rate *= OSC; + rate >>= 1; + + return rate; +} + +static const struct clk_ops ls1x_pll_clk_ops = { + .recalc_rate = ls1x_pll_recalc_rate, +}; + +static const char *const cpu_parents[] = { "cpu_clk_div", "osc_clk", }; +static const char *const ahb_parents[] = { "ahb_clk_div", "osc_clk", }; +static const char *const dc_parents[] = { "dc_clk_div", "osc_clk", }; + +void __init ls1x_clk_init(void) +{ + struct clk_hw *hw; + + hw = clk_hw_register_fixed_rate(NULL, "osc_clk", NULL, 0, OSC); + clk_hw_register_clkdev(hw, "osc_clk", NULL); + + /* clock derived from 33 MHz OSC clk */ + hw = clk_hw_register_pll(NULL, "pll_clk", "osc_clk", + &ls1x_pll_clk_ops, 0); + clk_hw_register_clkdev(hw, "pll_clk", NULL); + + /* clock derived from PLL clk */ + /* _____ + * _______________________| | + * OSC ___/ | MUX |___ CPU CLK + * \___ PLL ___ CPU DIV ___| | + * |_____| + */ + hw = clk_hw_register_divider(NULL, "cpu_clk_div", "pll_clk", + CLK_GET_RATE_NOCACHE, LS1X_CLK_PLL_DIV, + DIV_CPU_SHIFT, DIV_CPU_WIDTH, + CLK_DIVIDER_ONE_BASED | + CLK_DIVIDER_ROUND_CLOSEST, &_lock); + clk_hw_register_clkdev(hw, "cpu_clk_div", NULL); + hw = clk_hw_register_mux(NULL, "cpu_clk", cpu_parents, + ARRAY_SIZE(cpu_parents), + CLK_SET_RATE_NO_REPARENT, LS1X_CLK_PLL_DIV, + BYPASS_CPU_SHIFT, BYPASS_CPU_WIDTH, 0, &_lock); + clk_hw_register_clkdev(hw, "cpu_clk", NULL); + + /* _____ + * _______________________| | + * OSC ___/ | MUX |___ DC CLK + * \___ PLL ___ DC DIV ___| | + * |_____| + */ + hw = clk_hw_register_divider(NULL, "dc_clk_div", "pll_clk", + 0, LS1X_CLK_PLL_DIV, DIV_DC_SHIFT, + DIV_DC_WIDTH, CLK_DIVIDER_ONE_BASED, &_lock); + clk_hw_register_clkdev(hw, "dc_clk_div", NULL); + hw = clk_hw_register_mux(NULL, "dc_clk", dc_parents, + ARRAY_SIZE(dc_parents), + CLK_SET_RATE_NO_REPARENT, LS1X_CLK_PLL_DIV, + BYPASS_DC_SHIFT, BYPASS_DC_WIDTH, 0, &_lock); + clk_hw_register_clkdev(hw, "dc_clk", NULL); + + /* _____ + * _______________________| | + * OSC ___/ | MUX |___ DDR CLK + * \___ PLL ___ DDR DIV ___| | + * |_____| + */ + hw = clk_hw_register_divider(NULL, "ahb_clk_div", "pll_clk", + 0, LS1X_CLK_PLL_DIV, DIV_DDR_SHIFT, + DIV_DDR_WIDTH, CLK_DIVIDER_ONE_BASED, + &_lock); + clk_hw_register_clkdev(hw, "ahb_clk_div", NULL); + hw = clk_hw_register_mux(NULL, "ahb_clk", ahb_parents, + ARRAY_SIZE(ahb_parents), + CLK_SET_RATE_NO_REPARENT, LS1X_CLK_PLL_DIV, + BYPASS_DDR_SHIFT, BYPASS_DDR_WIDTH, 0, &_lock); + clk_hw_register_clkdev(hw, "ahb_clk", NULL); + clk_hw_register_clkdev(hw, "ls1x-dma", NULL); + clk_hw_register_clkdev(hw, "stmmaceth", NULL); + + /* clock derived from AHB clk */ + /* APB clk is always half of the AHB clk */ + hw = clk_hw_register_fixed_factor(NULL, "apb_clk", "ahb_clk", 0, 1, + DIV_APB); + clk_hw_register_clkdev(hw, "apb_clk", NULL); + clk_hw_register_clkdev(hw, "ls1x-ac97", NULL); + clk_hw_register_clkdev(hw, "ls1x-i2c", NULL); + clk_hw_register_clkdev(hw, "ls1x-nand", NULL); + clk_hw_register_clkdev(hw, "ls1x-pwmtimer", NULL); + clk_hw_register_clkdev(hw, "ls1x-spi", NULL); + clk_hw_register_clkdev(hw, "ls1x-wdt", NULL); + clk_hw_register_clkdev(hw, "serial8250", NULL); +} |