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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * Copyright 2013 Emilio López4 *5 * Emilio López <emilio@elopez.com.ar>6 */7 8#include <linux/clk.h>9#include <linux/clk-provider.h>10#include <linux/io.h>11#include <linux/of_address.h>12#include <linux/platform_device.h>13#include <linux/slab.h>14 15#include "clk-factors.h"16 17/*18 * sun4i_a10_get_mod0_factors() - calculates m, n factors for MOD0-style clocks19 * MOD0 rate is calculated as follows20 * rate = (parent_rate >> p) / (m + 1);21 */22 23static void sun4i_a10_get_mod0_factors(struct factors_request *req)24{25	u8 div, calcm, calcp;26 27	/* These clocks can only divide, so we will never be able to achieve28	 * frequencies higher than the parent frequency */29	if (req->rate > req->parent_rate)30		req->rate = req->parent_rate;31 32	div = DIV_ROUND_UP(req->parent_rate, req->rate);33 34	if (div < 16)35		calcp = 0;36	else if (div / 2 < 16)37		calcp = 1;38	else if (div / 4 < 16)39		calcp = 2;40	else41		calcp = 3;42 43	calcm = DIV_ROUND_UP(div, 1 << calcp);44 45	req->rate = (req->parent_rate >> calcp) / calcm;46	req->m = calcm - 1;47	req->p = calcp;48}49 50/* user manual says "n" but it's really "p" */51static const struct clk_factors_config sun4i_a10_mod0_config = {52	.mshift = 0,53	.mwidth = 4,54	.pshift = 16,55	.pwidth = 2,56};57 58static const struct factors_data sun4i_a10_mod0_data = {59	.enable = 31,60	.mux = 24,61	.muxmask = BIT(1) | BIT(0),62	.table = &sun4i_a10_mod0_config,63	.getter = sun4i_a10_get_mod0_factors,64};65 66static DEFINE_SPINLOCK(sun4i_a10_mod0_lock);67 68static void __init sun4i_a10_mod0_setup(struct device_node *node)69{70	void __iomem *reg;71 72	reg = of_iomap(node, 0);73	if (!reg) {74		/*75		 * This happens with mod0 clk nodes instantiated through76		 * mfd, as those do not have their resources assigned at77		 * CLK_OF_DECLARE time yet, so do not print an error.78		 */79		return;80	}81 82	sunxi_factors_register(node, &sun4i_a10_mod0_data,83			       &sun4i_a10_mod0_lock, reg);84}85CLK_OF_DECLARE_DRIVER(sun4i_a10_mod0, "allwinner,sun4i-a10-mod0-clk",86		      sun4i_a10_mod0_setup);87 88static int sun4i_a10_mod0_clk_probe(struct platform_device *pdev)89{90	struct device_node *np = pdev->dev.of_node;91	void __iomem *reg;92 93	if (!np)94		return -ENODEV;95 96	reg = devm_platform_ioremap_resource(pdev, 0);97	if (IS_ERR(reg))98		return PTR_ERR(reg);99 100	sunxi_factors_register(np, &sun4i_a10_mod0_data,101			       &sun4i_a10_mod0_lock, reg);102	return 0;103}104 105static const struct of_device_id sun4i_a10_mod0_clk_dt_ids[] = {106	{ .compatible = "allwinner,sun4i-a10-mod0-clk" },107	{ /* sentinel */ }108};109 110static struct platform_driver sun4i_a10_mod0_clk_driver = {111	.driver = {112		.name = "sun4i-a10-mod0-clk",113		.of_match_table = sun4i_a10_mod0_clk_dt_ids,114	},115	.probe = sun4i_a10_mod0_clk_probe,116};117builtin_platform_driver(sun4i_a10_mod0_clk_driver);118 119static const struct factors_data sun9i_a80_mod0_data __initconst = {120	.enable = 31,121	.mux = 24,122	.muxmask = BIT(3) | BIT(2) | BIT(1) | BIT(0),123	.table = &sun4i_a10_mod0_config,124	.getter = sun4i_a10_get_mod0_factors,125};126 127static void __init sun9i_a80_mod0_setup(struct device_node *node)128{129	void __iomem *reg;130 131	reg = of_io_request_and_map(node, 0, of_node_full_name(node));132	if (IS_ERR(reg)) {133		pr_err("Could not get registers for mod0-clk: %pOFn\n",134		       node);135		return;136	}137 138	sunxi_factors_register(node, &sun9i_a80_mod0_data,139			       &sun4i_a10_mod0_lock, reg);140}141CLK_OF_DECLARE(sun9i_a80_mod0, "allwinner,sun9i-a80-mod0-clk", sun9i_a80_mod0_setup);142 143static DEFINE_SPINLOCK(sun5i_a13_mbus_lock);144 145static void __init sun5i_a13_mbus_setup(struct device_node *node)146{147	void __iomem *reg;148 149	reg = of_iomap(node, 0);150	if (!reg) {151		pr_err("Could not get registers for a13-mbus-clk\n");152		return;153	}154 155	/* The MBUS clocks needs to be always enabled */156	sunxi_factors_register_critical(node, &sun4i_a10_mod0_data,157					&sun5i_a13_mbus_lock, reg);158}159CLK_OF_DECLARE(sun5i_a13_mbus, "allwinner,sun5i-a13-mbus-clk", sun5i_a13_mbus_setup);160 161struct mmc_phase {162	struct clk_hw		hw;163	u8			offset;164	void __iomem		*reg;165	spinlock_t		*lock;166};167 168#define to_mmc_phase(_hw) container_of(_hw, struct mmc_phase, hw)169 170static int mmc_get_phase(struct clk_hw *hw)171{172	struct clk *mmc, *mmc_parent, *clk = hw->clk;173	struct mmc_phase *phase = to_mmc_phase(hw);174	unsigned int mmc_rate, mmc_parent_rate;175	u16 step, mmc_div;176	u32 value;177	u8 delay;178 179	value = readl(phase->reg);180	delay = (value >> phase->offset) & 0x3;181 182	if (!delay)183		return 180;184 185	/* Get the main MMC clock */186	mmc = clk_get_parent(clk);187	if (!mmc)188		return -EINVAL;189 190	/* And its rate */191	mmc_rate = clk_get_rate(mmc);192	if (!mmc_rate)193		return -EINVAL;194 195	/* Now, get the MMC parent (most likely some PLL) */196	mmc_parent = clk_get_parent(mmc);197	if (!mmc_parent)198		return -EINVAL;199 200	/* And its rate */201	mmc_parent_rate = clk_get_rate(mmc_parent);202	if (!mmc_parent_rate)203		return -EINVAL;204 205	/* Get MMC clock divider */206	mmc_div = mmc_parent_rate / mmc_rate;207 208	step = DIV_ROUND_CLOSEST(360, mmc_div);209	return delay * step;210}211 212static int mmc_set_phase(struct clk_hw *hw, int degrees)213{214	struct clk *mmc, *mmc_parent, *clk = hw->clk;215	struct mmc_phase *phase = to_mmc_phase(hw);216	unsigned int mmc_rate, mmc_parent_rate;217	unsigned long flags;218	u32 value;219	u8 delay;220 221	/* Get the main MMC clock */222	mmc = clk_get_parent(clk);223	if (!mmc)224		return -EINVAL;225 226	/* And its rate */227	mmc_rate = clk_get_rate(mmc);228	if (!mmc_rate)229		return -EINVAL;230 231	/* Now, get the MMC parent (most likely some PLL) */232	mmc_parent = clk_get_parent(mmc);233	if (!mmc_parent)234		return -EINVAL;235 236	/* And its rate */237	mmc_parent_rate = clk_get_rate(mmc_parent);238	if (!mmc_parent_rate)239		return -EINVAL;240 241	if (degrees != 180) {242		u16 step, mmc_div;243 244		/* Get MMC clock divider */245		mmc_div = mmc_parent_rate / mmc_rate;246 247		/*248		 * We can only outphase the clocks by multiple of the249		 * PLL's period.250		 *251		 * Since the MMC clock in only a divider, and the252		 * formula to get the outphasing in degrees is deg =253		 * 360 * delta / period254		 *255		 * If we simplify this formula, we can see that the256		 * only thing that we're concerned about is the number257		 * of period we want to outphase our clock from, and258		 * the divider set by the MMC clock.259		 */260		step = DIV_ROUND_CLOSEST(360, mmc_div);261		delay = DIV_ROUND_CLOSEST(degrees, step);262	} else {263		delay = 0;264	}265 266	spin_lock_irqsave(phase->lock, flags);267	value = readl(phase->reg);268	value &= ~GENMASK(phase->offset + 3, phase->offset);269	value |= delay << phase->offset;270	writel(value, phase->reg);271	spin_unlock_irqrestore(phase->lock, flags);272 273	return 0;274}275 276static const struct clk_ops mmc_clk_ops = {277	.get_phase	= mmc_get_phase,278	.set_phase	= mmc_set_phase,279};280 281/*282 * sunxi_mmc_setup - Common setup function for mmc module clocks283 *284 * The only difference between module clocks on different platforms is the285 * width of the mux register bits and the valid values, which are passed in286 * through struct factors_data. The phase clocks parts are identical.287 */288static void __init sunxi_mmc_setup(struct device_node *node,289				   const struct factors_data *data,290				   spinlock_t *lock)291{292	struct clk_onecell_data *clk_data;293	const char *parent;294	void __iomem *reg;295	int i;296 297	reg = of_io_request_and_map(node, 0, of_node_full_name(node));298	if (IS_ERR(reg)) {299		pr_err("Couldn't map the %pOFn clock registers\n", node);300		return;301	}302 303	clk_data = kmalloc(sizeof(*clk_data), GFP_KERNEL);304	if (!clk_data)305		return;306 307	clk_data->clks = kcalloc(3, sizeof(*clk_data->clks), GFP_KERNEL);308	if (!clk_data->clks)309		goto err_free_data;310 311	clk_data->clk_num = 3;312	clk_data->clks[0] = sunxi_factors_register(node, data, lock, reg);313	if (!clk_data->clks[0])314		goto err_free_clks;315 316	parent = __clk_get_name(clk_data->clks[0]);317 318	for (i = 1; i < 3; i++) {319		struct clk_init_data init = {320			.num_parents	= 1,321			.parent_names	= &parent,322			.ops		= &mmc_clk_ops,323		};324		struct mmc_phase *phase;325 326		phase = kmalloc(sizeof(*phase), GFP_KERNEL);327		if (!phase)328			continue;329 330		phase->hw.init = &init;331		phase->reg = reg;332		phase->lock = lock;333 334		if (i == 1)335			phase->offset = 8;336		else337			phase->offset = 20;338 339		if (of_property_read_string_index(node, "clock-output-names",340						  i, &init.name))341			init.name = node->name;342 343		clk_data->clks[i] = clk_register(NULL, &phase->hw);344		if (IS_ERR(clk_data->clks[i])) {345			kfree(phase);346			continue;347		}348	}349 350	of_clk_add_provider(node, of_clk_src_onecell_get, clk_data);351 352	return;353 354err_free_clks:355	kfree(clk_data->clks);356err_free_data:357	kfree(clk_data);358}359 360static DEFINE_SPINLOCK(sun4i_a10_mmc_lock);361 362static void __init sun4i_a10_mmc_setup(struct device_node *node)363{364	sunxi_mmc_setup(node, &sun4i_a10_mod0_data, &sun4i_a10_mmc_lock);365}366CLK_OF_DECLARE(sun4i_a10_mmc, "allwinner,sun4i-a10-mmc-clk", sun4i_a10_mmc_setup);367 368static DEFINE_SPINLOCK(sun9i_a80_mmc_lock);369 370static void __init sun9i_a80_mmc_setup(struct device_node *node)371{372	sunxi_mmc_setup(node, &sun9i_a80_mod0_data, &sun9i_a80_mmc_lock);373}374CLK_OF_DECLARE(sun9i_a80_mmc, "allwinner,sun9i-a80-mmc-clk", sun9i_a80_mmc_setup);375