brintos

brintos / linux-shallow public Read only

0
0
Text · 16.7 KiB · f2117fe Raw
709 lines · c
1// SPDX-License-Identifier: GPL-2.0-only2/*3 * TI clock support4 *5 * Copyright (C) 2013 Texas Instruments, Inc.6 *7 * Tero Kristo <t-kristo@ti.com>8 */9 10#include <linux/cleanup.h>11#include <linux/clk.h>12#include <linux/clk-provider.h>13#include <linux/clkdev.h>14#include <linux/clk/ti.h>15#include <linux/io.h>16#include <linux/of.h>17#include <linux/of_address.h>18#include <linux/list.h>19#include <linux/minmax.h>20#include <linux/regmap.h>21#include <linux/string_helpers.h>22#include <linux/memblock.h>23#include <linux/device.h>24 25#include "clock.h"26 27#undef pr_fmt28#define pr_fmt(fmt) "%s: " fmt, __func__29 30static LIST_HEAD(clk_hw_omap_clocks);31struct ti_clk_ll_ops *ti_clk_ll_ops;32static struct device_node *clocks_node_ptr[CLK_MAX_MEMMAPS];33 34struct ti_clk_features ti_clk_features;35 36struct clk_iomap {37	struct regmap *regmap;38	void __iomem *mem;39};40 41static struct clk_iomap *clk_memmaps[CLK_MAX_MEMMAPS];42 43static void clk_memmap_writel(u32 val, const struct clk_omap_reg *reg)44{45	struct clk_iomap *io = clk_memmaps[reg->index];46 47	if (reg->ptr)48		writel_relaxed(val, reg->ptr);49	else if (io->regmap)50		regmap_write(io->regmap, reg->offset, val);51	else52		writel_relaxed(val, io->mem + reg->offset);53}54 55static void _clk_rmw(u32 val, u32 mask, void __iomem *ptr)56{57	u32 v;58 59	v = readl_relaxed(ptr);60	v &= ~mask;61	v |= val;62	writel_relaxed(v, ptr);63}64 65static void clk_memmap_rmw(u32 val, u32 mask, const struct clk_omap_reg *reg)66{67	struct clk_iomap *io = clk_memmaps[reg->index];68 69	if (reg->ptr) {70		_clk_rmw(val, mask, reg->ptr);71	} else if (io->regmap) {72		regmap_update_bits(io->regmap, reg->offset, mask, val);73	} else {74		_clk_rmw(val, mask, io->mem + reg->offset);75	}76}77 78static u32 clk_memmap_readl(const struct clk_omap_reg *reg)79{80	u32 val;81	struct clk_iomap *io = clk_memmaps[reg->index];82 83	if (reg->ptr)84		val = readl_relaxed(reg->ptr);85	else if (io->regmap)86		regmap_read(io->regmap, reg->offset, &val);87	else88		val = readl_relaxed(io->mem + reg->offset);89 90	return val;91}92 93/**94 * ti_clk_setup_ll_ops - setup low level clock operations95 * @ops: low level clock ops descriptor96 *97 * Sets up low level clock operations for TI clock driver. This is used98 * to provide various callbacks for the clock driver towards platform99 * specific code. Returns 0 on success, -EBUSY if ll_ops have been100 * registered already.101 */102int ti_clk_setup_ll_ops(struct ti_clk_ll_ops *ops)103{104	if (ti_clk_ll_ops) {105		pr_err("Attempt to register ll_ops multiple times.\n");106		return -EBUSY;107	}108 109	ti_clk_ll_ops = ops;110	ops->clk_readl = clk_memmap_readl;111	ops->clk_writel = clk_memmap_writel;112	ops->clk_rmw = clk_memmap_rmw;113 114	return 0;115}116 117/*118 * Eventually we could standardize to using '_' for clk-*.c files to follow the119 * TRM naming.120 */121static struct device_node *ti_find_clock_provider(struct device_node *from,122						  const char *name)123{124	char *tmp __free(kfree) = NULL;125	struct device_node *np;126	bool found = false;127	const char *n;128	char *p;129 130	tmp = kstrdup_and_replace(name, '-', '_', GFP_KERNEL);131	if (!tmp)132		return NULL;133 134	/* Ignore a possible address for the node name */135	p = strchr(tmp, '@');136	if (p)137		*p = '\0';138 139	/* Node named "clock" with "clock-output-names" */140	for_each_of_allnodes_from(from, np) {141		if (of_property_read_string_index(np, "clock-output-names",142						  0, &n))143			continue;144 145		if (!strncmp(n, tmp, strlen(tmp))) {146			of_node_get(np);147			found = true;148			break;149		}150	}151 152	if (found) {153		of_node_put(from);154		return np;155	}156 157	/* Fall back to using old node name base provider name */158	return of_find_node_by_name(from, tmp);159}160 161/**162 * ti_dt_clocks_register - register DT alias clocks during boot163 * @oclks: list of clocks to register164 *165 * Register alias or non-standard DT clock entries during boot. By166 * default, DT clocks are found based on their clock-output-names167 * property, or the clock node name for legacy cases. If any168 * additional con-id / dev-id -> clock mapping is required, use this169 * function to list these.170 */171void __init ti_dt_clocks_register(struct ti_dt_clk oclks[])172{173	struct ti_dt_clk *c;174	struct device_node *node, *parent, *child;175	struct clk *clk;176	struct of_phandle_args clkspec;177	char buf[64];178	char *ptr;179	char *tags[2];180	int i;181	int num_args;182	int ret;183	static bool clkctrl_nodes_missing;184	static bool has_clkctrl_data;185	static bool compat_mode;186 187	compat_mode = ti_clk_get_features()->flags & TI_CLK_CLKCTRL_COMPAT;188 189	for (c = oclks; c->node_name != NULL; c++) {190		strcpy(buf, c->node_name);191		ptr = buf;192		for (i = 0; i < 2; i++)193			tags[i] = NULL;194		num_args = 0;195		while (*ptr) {196			if (*ptr == ':') {197				if (num_args >= 2) {198					pr_warn("Bad number of tags on %s\n",199						c->node_name);200					return;201				}202				tags[num_args++] = ptr + 1;203				*ptr = 0;204			}205			ptr++;206		}207 208		if (num_args && clkctrl_nodes_missing)209			continue;210 211		node = ti_find_clock_provider(NULL, buf);212		if (num_args && compat_mode) {213			parent = node;214			child = of_get_child_by_name(parent, "clock");215			if (!child)216				child = of_get_child_by_name(parent, "clk");217			if (child) {218				of_node_put(parent);219				node = child;220			}221		}222 223		clkspec.np = node;224		clkspec.args_count = num_args;225		for (i = 0; i < num_args; i++) {226			ret = kstrtoint(tags[i], i ? 10 : 16, clkspec.args + i);227			if (ret) {228				pr_warn("Bad tag in %s at %d: %s\n",229					c->node_name, i, tags[i]);230				of_node_put(node);231				return;232			}233		}234		clk = of_clk_get_from_provider(&clkspec);235		of_node_put(node);236		if (!IS_ERR(clk)) {237			c->lk.clk = clk;238			clkdev_add(&c->lk);239		} else {240			if (num_args && !has_clkctrl_data) {241				struct device_node *np;242 243				np = of_find_compatible_node(NULL, NULL,244							     "ti,clkctrl");245				if (np) {246					has_clkctrl_data = true;247					of_node_put(np);248				} else {249					clkctrl_nodes_missing = true;250 251					pr_warn("missing clkctrl nodes, please update your dts.\n");252					continue;253				}254			}255 256			pr_warn("failed to lookup clock node %s, ret=%ld\n",257				c->node_name, PTR_ERR(clk));258		}259	}260}261 262struct clk_init_item {263	struct device_node *node;264	void *user;265	ti_of_clk_init_cb_t func;266	struct list_head link;267};268 269static LIST_HEAD(retry_list);270 271/**272 * ti_clk_retry_init - retries a failed clock init at later phase273 * @node: device node for the clock274 * @user: user data pointer275 * @func: init function to be called for the clock276 *277 * Adds a failed clock init to the retry list. The retry list is parsed278 * once all the other clocks have been initialized.279 */280int __init ti_clk_retry_init(struct device_node *node, void *user,281			     ti_of_clk_init_cb_t func)282{283	struct clk_init_item *retry;284 285	pr_debug("%pOFn: adding to retry list...\n", node);286	retry = kzalloc(sizeof(*retry), GFP_KERNEL);287	if (!retry)288		return -ENOMEM;289 290	retry->node = node;291	retry->func = func;292	retry->user = user;293	list_add(&retry->link, &retry_list);294 295	return 0;296}297 298/**299 * ti_clk_get_reg_addr - get register address for a clock register300 * @node: device node for the clock301 * @index: register index from the clock node302 * @reg: pointer to target register struct303 *304 * Builds clock register address from device tree information, and returns305 * the data via the provided output pointer @reg. Returns 0 on success,306 * negative error value on failure.307 */308int ti_clk_get_reg_addr(struct device_node *node, int index,309			struct clk_omap_reg *reg)310{311	u32 clksel_addr, val;312	bool is_clksel = false;313	int i, err;314 315	for (i = 0; i < CLK_MAX_MEMMAPS; i++) {316		if (clocks_node_ptr[i] == node->parent)317			break;318		if (clocks_node_ptr[i] == node->parent->parent)319			break;320	}321 322	if (i == CLK_MAX_MEMMAPS) {323		pr_err("clk-provider not found for %pOFn!\n", node);324		return -ENOENT;325	}326 327	reg->index = i;328 329	if (of_device_is_compatible(node->parent, "ti,clksel")) {330		err = of_property_read_u32_index(node->parent, "reg", index, &clksel_addr);331		if (err) {332			pr_err("%pOFn parent clksel must have reg[%d]!\n", node, index);333			return -EINVAL;334		}335		is_clksel = true;336	}337 338	err = of_property_read_u32_index(node, "reg", index, &val);339	if (err && is_clksel) {340		/* Legacy clksel with no reg and a possible ti,bit-shift property */341		reg->offset = clksel_addr;342		reg->bit = ti_clk_get_legacy_bit_shift(node);343		reg->ptr = NULL;344 345		return 0;346	}347 348	/* Updated clksel clock with a proper reg property */349	if (is_clksel) {350		reg->offset = clksel_addr;351		reg->bit = val;352		reg->ptr = NULL;353		return 0;354	}355 356	/* Other clocks that may or may not have ti,bit-shift property  */357	reg->offset = val;358	reg->bit = ti_clk_get_legacy_bit_shift(node);359	reg->ptr = NULL;360 361	return 0;362}363 364/**365 * ti_clk_get_legacy_bit_shift - get bit shift for a clock register366 * @node: device node for the clock367 *368 * Gets the clock register bit shift using the legacy ti,bit-shift369 * property. Only needed for legacy clock, and can be eventually370 * dropped once all the composite clocks use a clksel node with a371 * proper reg property.372 */373int ti_clk_get_legacy_bit_shift(struct device_node *node)374{375	int err;376	u32 val;377 378	err = of_property_read_u32(node, "ti,bit-shift", &val);379	if (!err && in_range(val, 0, 32))380		return val;381 382	return 0;383}384 385void ti_clk_latch(struct clk_omap_reg *reg, s8 shift)386{387	u32 latch;388 389	if (shift < 0)390		return;391 392	latch = 1 << shift;393 394	ti_clk_ll_ops->clk_rmw(latch, latch, reg);395	ti_clk_ll_ops->clk_rmw(0, latch, reg);396	ti_clk_ll_ops->clk_readl(reg); /* OCP barrier */397}398 399/**400 * omap2_clk_provider_init - init master clock provider401 * @parent: master node402 * @index: internal index for clk_reg_ops403 * @syscon: syscon regmap pointer for accessing clock registers404 * @mem: iomem pointer for the clock provider memory area, only used if405 *       syscon is not provided406 *407 * Initializes a master clock IP block. This basically sets up the408 * mapping from clocks node to the memory map index. All the clocks409 * are then initialized through the common of_clk_init call, and the410 * clocks will access their memory maps based on the node layout.411 * Returns 0 in success.412 */413int __init omap2_clk_provider_init(struct device_node *parent, int index,414				   struct regmap *syscon, void __iomem *mem)415{416	struct device_node *clocks;417	struct clk_iomap *io;418 419	/* get clocks for this parent */420	clocks = of_get_child_by_name(parent, "clocks");421	if (!clocks) {422		pr_err("%pOFn missing 'clocks' child node.\n", parent);423		return -EINVAL;424	}425 426	/* add clocks node info */427	clocks_node_ptr[index] = clocks;428 429	io = kzalloc(sizeof(*io), GFP_KERNEL);430	if (!io)431		return -ENOMEM;432 433	io->regmap = syscon;434	io->mem = mem;435 436	clk_memmaps[index] = io;437 438	return 0;439}440 441/**442 * omap2_clk_legacy_provider_init - initialize a legacy clock provider443 * @index: index for the clock provider444 * @mem: iomem pointer for the clock provider memory area445 *446 * Initializes a legacy clock provider memory mapping.447 */448void __init omap2_clk_legacy_provider_init(int index, void __iomem *mem)449{450	struct clk_iomap *io;451 452	io = memblock_alloc(sizeof(*io), SMP_CACHE_BYTES);453	if (!io)454		panic("%s: Failed to allocate %zu bytes\n", __func__,455		      sizeof(*io));456 457	io->mem = mem;458 459	clk_memmaps[index] = io;460}461 462/**463 * ti_dt_clk_init_retry_clks - init clocks from the retry list464 *465 * Initializes any clocks that have failed to initialize before,466 * reasons being missing parent node(s) during earlier init. This467 * typically happens only for DPLLs which need to have both of their468 * parent clocks ready during init.469 */470void ti_dt_clk_init_retry_clks(void)471{472	struct clk_init_item *retry;473	struct clk_init_item *tmp;474	int retries = 5;475 476	while (!list_empty(&retry_list) && retries) {477		list_for_each_entry_safe(retry, tmp, &retry_list, link) {478			pr_debug("retry-init: %pOFn\n", retry->node);479			retry->func(retry->user, retry->node);480			list_del(&retry->link);481			kfree(retry);482		}483		retries--;484	}485}486 487static const struct of_device_id simple_clk_match_table[] __initconst = {488	{ .compatible = "fixed-clock" },489	{ .compatible = "fixed-factor-clock" },490	{ }491};492 493/**494 * ti_dt_clk_name - init clock name from first output name or node name495 * @np: device node496 *497 * Use the first clock-output-name for the clock name if found. Fall back498 * to legacy naming based on node name.499 */500const char *ti_dt_clk_name(struct device_node *np)501{502	const char *name;503 504	if (!of_property_read_string_index(np, "clock-output-names", 0,505					   &name))506		return name;507 508	return np->name;509}510 511/**512 * ti_clk_add_aliases - setup clock aliases513 *514 * Sets up any missing clock aliases. No return value.515 */516void __init ti_clk_add_aliases(void)517{518	struct device_node *np;519	struct clk *clk;520 521	for_each_matching_node(np, simple_clk_match_table) {522		struct of_phandle_args clkspec;523 524		clkspec.np = np;525		clk = of_clk_get_from_provider(&clkspec);526 527		ti_clk_add_alias(clk, ti_dt_clk_name(np));528	}529}530 531/**532 * ti_clk_setup_features - setup clock features flags533 * @features: features definition to use534 *535 * Initializes the clock driver features flags based on platform536 * provided data. No return value.537 */538void __init ti_clk_setup_features(struct ti_clk_features *features)539{540	memcpy(&ti_clk_features, features, sizeof(*features));541}542 543/**544 * ti_clk_get_features - get clock driver features flags545 *546 * Get TI clock driver features description. Returns a pointer547 * to the current feature setup.548 */549const struct ti_clk_features *ti_clk_get_features(void)550{551	return &ti_clk_features;552}553 554/**555 * omap2_clk_enable_init_clocks - prepare & enable a list of clocks556 * @clk_names: ptr to an array of strings of clock names to enable557 * @num_clocks: number of clock names in @clk_names558 *559 * Prepare and enable a list of clocks, named by @clk_names.  No560 * return value. XXX Deprecated; only needed until these clocks are561 * properly claimed and enabled by the drivers or core code that uses562 * them.  XXX What code disables & calls clk_put on these clocks?563 */564void omap2_clk_enable_init_clocks(const char **clk_names, u8 num_clocks)565{566	struct clk *init_clk;567	int i;568 569	for (i = 0; i < num_clocks; i++) {570		init_clk = clk_get(NULL, clk_names[i]);571		if (WARN(IS_ERR(init_clk), "could not find init clock %s\n",572			 clk_names[i]))573			continue;574		clk_prepare_enable(init_clk);575	}576}577 578/**579 * ti_clk_add_alias - add a clock alias for a TI clock580 * @clk: clock handle to create alias for581 * @con: connection ID for this clock582 *583 * Creates a clock alias for a TI clock. Allocates the clock lookup entry584 * and assigns the data to it. Returns 0 if successful, negative error585 * value otherwise.586 */587int ti_clk_add_alias(struct clk *clk, const char *con)588{589	struct clk_lookup *cl;590 591	if (!clk)592		return 0;593 594	if (IS_ERR(clk))595		return PTR_ERR(clk);596 597	cl = kzalloc(sizeof(*cl), GFP_KERNEL);598	if (!cl)599		return -ENOMEM;600 601	cl->con_id = con;602	cl->clk = clk;603 604	clkdev_add(cl);605 606	return 0;607}608 609/**610 * of_ti_clk_register - register a TI clock to the common clock framework611 * @node: device node for this clock612 * @hw: hardware clock handle613 * @con: connection ID for this clock614 *615 * Registers a TI clock to the common clock framework, and adds a clock616 * alias for it. Returns a handle to the registered clock if successful,617 * ERR_PTR value in failure.618 */619struct clk *of_ti_clk_register(struct device_node *node, struct clk_hw *hw,620			       const char *con)621{622	struct clk *clk;623	int ret;624 625	ret = of_clk_hw_register(node, hw);626	if (ret)627		return ERR_PTR(ret);628 629	clk = hw->clk;630	ret = ti_clk_add_alias(clk, con);631	if (ret) {632		clk_unregister(clk);633		return ERR_PTR(ret);634	}635 636	return clk;637}638 639/**640 * of_ti_clk_register_omap_hw - register a clk_hw_omap to the clock framework641 * @node: device node for this clock642 * @hw: hardware clock handle643 * @con: connection ID for this clock644 *645 * Registers a clk_hw_omap clock to the clock framewor, adds a clock alias646 * for it, and adds the list to the available clk_hw_omap type clocks.647 * Returns a handle to the registered clock if successful, ERR_PTR value648 * in failure.649 */650struct clk *of_ti_clk_register_omap_hw(struct device_node *node,651				       struct clk_hw *hw, const char *con)652{653	struct clk *clk;654	struct clk_hw_omap *oclk;655 656	clk = of_ti_clk_register(node, hw, con);657	if (IS_ERR(clk))658		return clk;659 660	oclk = to_clk_hw_omap(hw);661 662	list_add(&oclk->node, &clk_hw_omap_clocks);663 664	return clk;665}666 667/**668 * omap2_clk_for_each - call function for each registered clk_hw_omap669 * @fn: pointer to a callback function670 *671 * Call @fn for each registered clk_hw_omap, passing @hw to each672 * function.  @fn must return 0 for success or any other value for673 * failure.  If @fn returns non-zero, the iteration across clocks674 * will stop and the non-zero return value will be passed to the675 * caller of omap2_clk_for_each().676 */677int omap2_clk_for_each(int (*fn)(struct clk_hw_omap *hw))678{679	int ret;680	struct clk_hw_omap *hw;681 682	list_for_each_entry(hw, &clk_hw_omap_clocks, node) {683		ret = (*fn)(hw);684		if (ret)685			break;686	}687 688	return ret;689}690 691/**692 * omap2_clk_is_hw_omap - check if the provided clk_hw is OMAP clock693 * @hw: clk_hw to check if it is an omap clock or not694 *695 * Checks if the provided clk_hw is OMAP clock or not. Returns true if696 * it is, false otherwise.697 */698bool omap2_clk_is_hw_omap(struct clk_hw *hw)699{700	struct clk_hw_omap *oclk;701 702	list_for_each_entry(oclk, &clk_hw_omap_clocks, node) {703		if (&oclk->hw == hw)704			return true;705	}706 707	return false;708}709