diff options
Diffstat (limited to 'kernel/drivers/clk/sunxi/clk-mod0.c')
| -rw-r--r-- | kernel/drivers/clk/sunxi/clk-mod0.c | 392 |
1 files changed, 392 insertions, 0 deletions
diff --git a/kernel/drivers/clk/sunxi/clk-mod0.c b/kernel/drivers/clk/sunxi/clk-mod0.c new file mode 100644 index 000000000..ec8f5a1fc --- /dev/null +++ b/kernel/drivers/clk/sunxi/clk-mod0.c @@ -0,0 +1,392 @@ +/* + * 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 <linux/platform_device.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 = { + .enable = 31, + .mux = 24, + .muxmask = BIT(1) | BIT(0), + .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) +{ + void __iomem *reg; + + reg = of_iomap(node, 0); + if (!reg) { + /* + * This happens with mod0 clk nodes instantiated through + * mfd, as those do not have their resources assigned at + * CLK_OF_DECLARE time yet, so do not print an error. + */ + return; + } + + sunxi_factors_register(node, &sun4i_a10_mod0_data, + &sun4i_a10_mod0_lock, reg); +} +CLK_OF_DECLARE(sun4i_a10_mod0, "allwinner,sun4i-a10-mod0-clk", sun4i_a10_mod0_setup); + +static int sun4i_a10_mod0_clk_probe(struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node; + struct resource *r; + void __iomem *reg; + + if (!np) + return -ENODEV; + + r = platform_get_resource(pdev, IORESOURCE_MEM, 0); + reg = devm_ioremap_resource(&pdev->dev, r); + if (IS_ERR(reg)) + return PTR_ERR(reg); + + sunxi_factors_register(np, &sun4i_a10_mod0_data, + &sun4i_a10_mod0_lock, reg); + return 0; +} + +static const struct of_device_id sun4i_a10_mod0_clk_dt_ids[] = { + { .compatible = "allwinner,sun4i-a10-mod0-clk" }, + { /* sentinel */ } +}; + +static struct platform_driver sun4i_a10_mod0_clk_driver = { + .driver = { + .name = "sun4i-a10-mod0-clk", + .of_match_table = sun4i_a10_mod0_clk_dt_ids, + }, + .probe = sun4i_a10_mod0_clk_probe, +}; +module_platform_driver(sun4i_a10_mod0_clk_driver); + +static const struct factors_data sun9i_a80_mod0_data __initconst = { + .enable = 31, + .mux = 24, + .muxmask = BIT(3) | BIT(2) | BIT(1) | BIT(0), + .table = &sun4i_a10_mod0_config, + .getter = sun4i_a10_get_mod0_factors, +}; + +static void __init sun9i_a80_mod0_setup(struct device_node *node) +{ + void __iomem *reg; + + reg = of_io_request_and_map(node, 0, of_node_full_name(node)); + if (IS_ERR(reg)) { + pr_err("Could not get registers for mod0-clk: %s\n", + node->name); + return; + } + + sunxi_factors_register(node, &sun9i_a80_mod0_data, + &sun4i_a10_mod0_lock, reg); +} +CLK_OF_DECLARE(sun9i_a80_mod0, "allwinner,sun9i-a80-mod0-clk", sun9i_a80_mod0_setup); + +static DEFINE_SPINLOCK(sun5i_a13_mbus_lock); + +static void __init sun5i_a13_mbus_setup(struct device_node *node) +{ + struct clk *mbus; + void __iomem *reg; + + reg = of_iomap(node, 0); + if (!reg) { + pr_err("Could not get registers for a13-mbus-clk\n"); + return; + } + + mbus = sunxi_factors_register(node, &sun4i_a10_mod0_data, + &sun5i_a13_mbus_lock, reg); + + /* 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 { + struct clk_hw hw; + u8 offset; + void __iomem *reg; + 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->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->offset + 3, phase->offset); + value |= delay << phase->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, +}; + +/* + * sunxi_mmc_setup - Common setup function for mmc module clocks + * + * The only difference between module clocks on different platforms is the + * width of the mux register bits and the valid values, which are passed in + * through struct factors_data. The phase clocks parts are identical. + */ +static void __init sunxi_mmc_setup(struct device_node *node, + const struct factors_data *data, + spinlock_t *lock) +{ + struct clk_onecell_data *clk_data; + const char *parent; + void __iomem *reg; + int i; + + reg = of_io_request_and_map(node, 0, of_node_full_name(node)); + if (IS_ERR(reg)) { + pr_err("Couldn't map the %s clock registers\n", node->name); + return; + } + + clk_data = kmalloc(sizeof(*clk_data), GFP_KERNEL); + if (!clk_data) + return; + + clk_data->clks = kcalloc(3, sizeof(*clk_data->clks), GFP_KERNEL); + if (!clk_data->clks) + goto err_free_data; + + clk_data->clk_num = 3; + clk_data->clks[0] = sunxi_factors_register(node, data, lock, reg); + if (!clk_data->clks[0]) + goto err_free_clks; + + parent = __clk_get_name(clk_data->clks[0]); + + for (i = 1; i < 3; i++) { + struct clk_init_data init = { + .num_parents = 1, + .parent_names = &parent, + .ops = &mmc_clk_ops, + }; + struct mmc_phase *phase; + + phase = kmalloc(sizeof(*phase), GFP_KERNEL); + if (!phase) + continue; + + phase->hw.init = &init; + phase->reg = reg; + phase->lock = lock; + + if (i == 1) + phase->offset = 8; + else + phase->offset = 20; + + if (of_property_read_string_index(node, "clock-output-names", + i, &init.name)) + init.name = node->name; + + clk_data->clks[i] = clk_register(NULL, &phase->hw); + if (IS_ERR(clk_data->clks[i])) { + kfree(phase); + continue; + } + } + + of_clk_add_provider(node, of_clk_src_onecell_get, clk_data); + + return; + +err_free_clks: + kfree(clk_data->clks); +err_free_data: + kfree(clk_data); +} + +static DEFINE_SPINLOCK(sun4i_a10_mmc_lock); + +static void __init sun4i_a10_mmc_setup(struct device_node *node) +{ + sunxi_mmc_setup(node, &sun4i_a10_mod0_data, &sun4i_a10_mmc_lock); +} +CLK_OF_DECLARE(sun4i_a10_mmc, "allwinner,sun4i-a10-mmc-clk", sun4i_a10_mmc_setup); + +static DEFINE_SPINLOCK(sun9i_a80_mmc_lock); + +static void __init sun9i_a80_mmc_setup(struct device_node *node) +{ + sunxi_mmc_setup(node, &sun9i_a80_mod0_data, &sun9i_a80_mmc_lock); +} +CLK_OF_DECLARE(sun9i_a80_mmc, "allwinner,sun9i-a80-mmc-clk", sun9i_a80_mmc_setup); |