| /* |
| * 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/of_address.h> |
| |
| #include "clk-factors.h" |
| |
| /** |
| * sun4i_get_mod0_factors() - calculates m, n factors for MOD0-style clocks |
| * MOD0 rate is calculated as follows |
| * rate = (parent_rate >> p) / (m + 1); |
| */ |
| |
| static void sun4i_a10_get_mod0_factors(u32 *freq, u32 parent_rate, |
| u8 *n, u8 *k, u8 *m, u8 *p) |
| { |
| u8 div, calcm, calcp; |
| |
| /* These clocks can only divide, so we will never be able to achieve |
| * frequencies higher than the parent frequency */ |
| if (*freq > parent_rate) |
| *freq = parent_rate; |
| |
| div = DIV_ROUND_UP(parent_rate, *freq); |
| |
| if (div < 16) |
| calcp = 0; |
| else if (div / 2 < 16) |
| calcp = 1; |
| else if (div / 4 < 16) |
| calcp = 2; |
| else |
| calcp = 3; |
| |
| calcm = DIV_ROUND_UP(div, 1 << calcp); |
| |
| *freq = (parent_rate >> calcp) / calcm; |
| |
| /* we were called to round the frequency, we can now return */ |
| if (n == NULL) |
| return; |
| |
| *m = calcm - 1; |
| *p = calcp; |
| } |
| |
| /* user manual says "n" but it's really "p" */ |
| static struct clk_factors_config sun4i_a10_mod0_config = { |
| .mshift = 0, |
| .mwidth = 4, |
| .pshift = 16, |
| .pwidth = 2, |
| }; |
| |
| static const struct factors_data sun4i_a10_mod0_data __initconst = { |
| .enable = 31, |
| .mux = 24, |
| .table = &sun4i_a10_mod0_config, |
| .getter = sun4i_a10_get_mod0_factors, |
| }; |
| |
| static DEFINE_SPINLOCK(sun4i_a10_mod0_lock); |
| |
| static void __init sun4i_a10_mod0_setup(struct device_node *node) |
| { |
| sunxi_factors_register(node, &sun4i_a10_mod0_data, &sun4i_a10_mod0_lock); |
| } |
| CLK_OF_DECLARE(sun4i_a10_mod0, "allwinner,sun4i-a10-mod0-clk", sun4i_a10_mod0_setup); |
| |
| static DEFINE_SPINLOCK(sun5i_a13_mbus_lock); |
| |
| static void __init sun5i_a13_mbus_setup(struct device_node *node) |
| { |
| struct clk *mbus = sunxi_factors_register(node, &sun4i_a10_mod0_data, &sun5i_a13_mbus_lock); |
| |
| /* The MBUS clocks needs to be always enabled */ |
| __clk_get(mbus); |
| clk_prepare_enable(mbus); |
| } |
| CLK_OF_DECLARE(sun5i_a13_mbus, "allwinner,sun5i-a13-mbus-clk", sun5i_a13_mbus_setup); |
| |
| struct mmc_phase_data { |
| u8 offset; |
| }; |
| |
| struct mmc_phase { |
| struct clk_hw hw; |
| void __iomem *reg; |
| struct mmc_phase_data *data; |
| spinlock_t *lock; |
| }; |
| |
| #define to_mmc_phase(_hw) container_of(_hw, struct mmc_phase, hw) |
| |
| static int mmc_get_phase(struct clk_hw *hw) |
| { |
| struct clk *mmc, *mmc_parent, *clk = hw->clk; |
| struct mmc_phase *phase = to_mmc_phase(hw); |
| unsigned int mmc_rate, mmc_parent_rate; |
| u16 step, mmc_div; |
| u32 value; |
| u8 delay; |
| |
| value = readl(phase->reg); |
| delay = (value >> phase->data->offset) & 0x3; |
| |
| if (!delay) |
| return 180; |
| |
| /* Get the main MMC clock */ |
| mmc = clk_get_parent(clk); |
| if (!mmc) |
| return -EINVAL; |
| |
| /* And its rate */ |
| mmc_rate = clk_get_rate(mmc); |
| if (!mmc_rate) |
| return -EINVAL; |
| |
| /* Now, get the MMC parent (most likely some PLL) */ |
| mmc_parent = clk_get_parent(mmc); |
| if (!mmc_parent) |
| return -EINVAL; |
| |
| /* And its rate */ |
| mmc_parent_rate = clk_get_rate(mmc_parent); |
| if (!mmc_parent_rate) |
| return -EINVAL; |
| |
| /* Get MMC clock divider */ |
| mmc_div = mmc_parent_rate / mmc_rate; |
| |
| step = DIV_ROUND_CLOSEST(360, mmc_div); |
| return delay * step; |
| } |
| |
| static int mmc_set_phase(struct clk_hw *hw, int degrees) |
| { |
| struct clk *mmc, *mmc_parent, *clk = hw->clk; |
| struct mmc_phase *phase = to_mmc_phase(hw); |
| unsigned int mmc_rate, mmc_parent_rate; |
| unsigned long flags; |
| u32 value; |
| u8 delay; |
| |
| /* Get the main MMC clock */ |
| mmc = clk_get_parent(clk); |
| if (!mmc) |
| return -EINVAL; |
| |
| /* And its rate */ |
| mmc_rate = clk_get_rate(mmc); |
| if (!mmc_rate) |
| return -EINVAL; |
| |
| /* Now, get the MMC parent (most likely some PLL) */ |
| mmc_parent = clk_get_parent(mmc); |
| if (!mmc_parent) |
| return -EINVAL; |
| |
| /* And its rate */ |
| mmc_parent_rate = clk_get_rate(mmc_parent); |
| if (!mmc_parent_rate) |
| return -EINVAL; |
| |
| if (degrees != 180) { |
| u16 step, mmc_div; |
| |
| /* Get MMC clock divider */ |
| mmc_div = mmc_parent_rate / mmc_rate; |
| |
| /* |
| * We can only outphase the clocks by multiple of the |
| * PLL's period. |
| * |
| * Since the MMC clock in only a divider, and the |
| * formula to get the outphasing in degrees is deg = |
| * 360 * delta / period |
| * |
| * If we simplify this formula, we can see that the |
| * only thing that we're concerned about is the number |
| * of period we want to outphase our clock from, and |
| * the divider set by the MMC clock. |
| */ |
| step = DIV_ROUND_CLOSEST(360, mmc_div); |
| delay = DIV_ROUND_CLOSEST(degrees, step); |
| } else { |
| delay = 0; |
| } |
| |
| spin_lock_irqsave(phase->lock, flags); |
| value = readl(phase->reg); |
| value &= ~GENMASK(phase->data->offset + 3, phase->data->offset); |
| value |= delay << phase->data->offset; |
| writel(value, phase->reg); |
| spin_unlock_irqrestore(phase->lock, flags); |
| |
| return 0; |
| } |
| |
| static const struct clk_ops mmc_clk_ops = { |
| .get_phase = mmc_get_phase, |
| .set_phase = mmc_set_phase, |
| }; |
| |
| static void __init sun4i_a10_mmc_phase_setup(struct device_node *node, |
| struct mmc_phase_data *data) |
| { |
| const char *parent_names[1] = { of_clk_get_parent_name(node, 0) }; |
| struct clk_init_data init = { |
| .num_parents = 1, |
| .parent_names = parent_names, |
| .ops = &mmc_clk_ops, |
| }; |
| |
| struct mmc_phase *phase; |
| struct clk *clk; |
| |
| phase = kmalloc(sizeof(*phase), GFP_KERNEL); |
| if (!phase) |
| return; |
| |
| phase->hw.init = &init; |
| |
| phase->reg = of_iomap(node, 0); |
| if (!phase->reg) |
| goto err_free; |
| |
| phase->data = data; |
| phase->lock = &sun4i_a10_mod0_lock; |
| |
| if (of_property_read_string(node, "clock-output-names", &init.name)) |
| init.name = node->name; |
| |
| clk = clk_register(NULL, &phase->hw); |
| if (IS_ERR(clk)) |
| goto err_unmap; |
| |
| of_clk_add_provider(node, of_clk_src_simple_get, clk); |
| |
| return; |
| |
| err_unmap: |
| iounmap(phase->reg); |
| err_free: |
| kfree(phase); |
| } |
| |
| |
| static struct mmc_phase_data mmc_output_clk = { |
| .offset = 8, |
| }; |
| |
| static struct mmc_phase_data mmc_sample_clk = { |
| .offset = 20, |
| }; |
| |
| static void __init sun4i_a10_mmc_output_setup(struct device_node *node) |
| { |
| sun4i_a10_mmc_phase_setup(node, &mmc_output_clk); |
| } |
| CLK_OF_DECLARE(sun4i_a10_mmc_output, "allwinner,sun4i-a10-mmc-output-clk", sun4i_a10_mmc_output_setup); |
| |
| static void __init sun4i_a10_mmc_sample_setup(struct device_node *node) |
| { |
| sun4i_a10_mmc_phase_setup(node, &mmc_sample_clk); |
| } |
| CLK_OF_DECLARE(sun4i_a10_mmc_sample, "allwinner,sun4i-a10-mmc-sample-clk", sun4i_a10_mmc_sample_setup); |