linux/drivers/clk/ti/clk.c
Tony Lindgren 6c30905205 clk: ti: clkctrl: Fix hidden dependency to node name
We currently have a hidden dependency to the device tree node name for
the clkctrl clocks. Instead of using standard node name like "clock", we
must use "l4-per-clkctrl" type naming so the clock driver can find the
associated clock domain. Further, if "clk" is specified for a clock node
name, the driver sets TI_CLK_CLKCTRL_COMPAT flag that uses different
logic for the clock name based on the parent node name for the all the
clkctrl clocks for the SoC.

If the clock node naming dependency is not understood, the related
clockdomain is not found, or a wrong one can get used if a clock manager
has multiple clock domains.

As each clkctrl instance represents a single clock domain, let's allow
using domain specific compatible names to specify the clock domain.

This simplifies things and removes the hidden dependency to the node
name. And then later on, after the node names have been standardized,
we can drop the related code for parsing the node names.

Let's also update the binding to use standard "clock" node naming
instead of "clk" and add the missing description for reg.

Cc: devicetree@vger.kernel.org
Cc: Rob Herring <robh+dt@kernel.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Tero Kristo <t-kristo@ti.com>
2020-01-20 12:29:27 +02:00

602 lines
14 KiB
C

/*
* TI clock support
*
* Copyright (C) 2013 Texas Instruments, Inc.
*
* Tero Kristo <t-kristo@ti.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed "as is" WITHOUT ANY WARRANTY of any
* kind, whether express or implied; 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.h>
#include <linux/clk-provider.h>
#include <linux/clkdev.h>
#include <linux/clk/ti.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/list.h>
#include <linux/regmap.h>
#include <linux/memblock.h>
#include <linux/device.h>
#include "clock.h"
#undef pr_fmt
#define pr_fmt(fmt) "%s: " fmt, __func__
static LIST_HEAD(clk_hw_omap_clocks);
struct ti_clk_ll_ops *ti_clk_ll_ops;
static struct device_node *clocks_node_ptr[CLK_MAX_MEMMAPS];
struct ti_clk_features ti_clk_features;
struct clk_iomap {
struct regmap *regmap;
void __iomem *mem;
};
static struct clk_iomap *clk_memmaps[CLK_MAX_MEMMAPS];
static void clk_memmap_writel(u32 val, const struct clk_omap_reg *reg)
{
struct clk_iomap *io = clk_memmaps[reg->index];
if (reg->ptr)
writel_relaxed(val, reg->ptr);
else if (io->regmap)
regmap_write(io->regmap, reg->offset, val);
else
writel_relaxed(val, io->mem + reg->offset);
}
static void _clk_rmw(u32 val, u32 mask, void __iomem *ptr)
{
u32 v;
v = readl_relaxed(ptr);
v &= ~mask;
v |= val;
writel_relaxed(v, ptr);
}
static void clk_memmap_rmw(u32 val, u32 mask, const struct clk_omap_reg *reg)
{
struct clk_iomap *io = clk_memmaps[reg->index];
if (reg->ptr) {
_clk_rmw(val, mask, reg->ptr);
} else if (io->regmap) {
regmap_update_bits(io->regmap, reg->offset, mask, val);
} else {
_clk_rmw(val, mask, io->mem + reg->offset);
}
}
static u32 clk_memmap_readl(const struct clk_omap_reg *reg)
{
u32 val;
struct clk_iomap *io = clk_memmaps[reg->index];
if (reg->ptr)
val = readl_relaxed(reg->ptr);
else if (io->regmap)
regmap_read(io->regmap, reg->offset, &val);
else
val = readl_relaxed(io->mem + reg->offset);
return val;
}
/**
* ti_clk_setup_ll_ops - setup low level clock operations
* @ops: low level clock ops descriptor
*
* Sets up low level clock operations for TI clock driver. This is used
* to provide various callbacks for the clock driver towards platform
* specific code. Returns 0 on success, -EBUSY if ll_ops have been
* registered already.
*/
int ti_clk_setup_ll_ops(struct ti_clk_ll_ops *ops)
{
if (ti_clk_ll_ops) {
pr_err("Attempt to register ll_ops multiple times.\n");
return -EBUSY;
}
ti_clk_ll_ops = ops;
ops->clk_readl = clk_memmap_readl;
ops->clk_writel = clk_memmap_writel;
ops->clk_rmw = clk_memmap_rmw;
return 0;
}
/**
* ti_dt_clocks_register - register DT alias clocks during boot
* @oclks: list of clocks to register
*
* Register alias or non-standard DT clock entries during boot. By
* default, DT clocks are found based on their node name. If any
* additional con-id / dev-id -> clock mapping is required, use this
* function to list these.
*/
void __init ti_dt_clocks_register(struct ti_dt_clk oclks[])
{
struct ti_dt_clk *c;
struct device_node *node, *parent;
struct clk *clk;
struct of_phandle_args clkspec;
char buf[64];
char *ptr;
char *tags[2];
int i;
int num_args;
int ret;
static bool clkctrl_nodes_missing;
static bool has_clkctrl_data;
static bool compat_mode;
compat_mode = ti_clk_get_features()->flags & TI_CLK_CLKCTRL_COMPAT;
for (c = oclks; c->node_name != NULL; c++) {
strcpy(buf, c->node_name);
ptr = buf;
for (i = 0; i < 2; i++)
tags[i] = NULL;
num_args = 0;
while (*ptr) {
if (*ptr == ':') {
if (num_args >= 2) {
pr_warn("Bad number of tags on %s\n",
c->node_name);
return;
}
tags[num_args++] = ptr + 1;
*ptr = 0;
}
ptr++;
}
if (num_args && clkctrl_nodes_missing)
continue;
node = of_find_node_by_name(NULL, buf);
if (num_args && compat_mode) {
parent = node;
node = of_get_child_by_name(parent, "clock");
if (!node)
node = of_get_child_by_name(parent, "clk");
of_node_put(parent);
}
clkspec.np = node;
clkspec.args_count = num_args;
for (i = 0; i < num_args; i++) {
ret = kstrtoint(tags[i], i ? 10 : 16, clkspec.args + i);
if (ret) {
pr_warn("Bad tag in %s at %d: %s\n",
c->node_name, i, tags[i]);
of_node_put(node);
return;
}
}
clk = of_clk_get_from_provider(&clkspec);
of_node_put(node);
if (!IS_ERR(clk)) {
c->lk.clk = clk;
clkdev_add(&c->lk);
} else {
if (num_args && !has_clkctrl_data) {
struct device_node *np;
np = of_find_compatible_node(NULL, NULL,
"ti,clkctrl");
if (np) {
has_clkctrl_data = true;
of_node_put(np);
} else {
clkctrl_nodes_missing = true;
pr_warn("missing clkctrl nodes, please update your dts.\n");
continue;
}
}
pr_warn("failed to lookup clock node %s, ret=%ld\n",
c->node_name, PTR_ERR(clk));
}
}
}
struct clk_init_item {
struct device_node *node;
void *user;
ti_of_clk_init_cb_t func;
struct list_head link;
};
static LIST_HEAD(retry_list);
/**
* ti_clk_retry_init - retries a failed clock init at later phase
* @node: device not for the clock
* @user: user data pointer
* @func: init function to be called for the clock
*
* Adds a failed clock init to the retry list. The retry list is parsed
* once all the other clocks have been initialized.
*/
int __init ti_clk_retry_init(struct device_node *node, void *user,
ti_of_clk_init_cb_t func)
{
struct clk_init_item *retry;
pr_debug("%pOFn: adding to retry list...\n", node);
retry = kzalloc(sizeof(*retry), GFP_KERNEL);
if (!retry)
return -ENOMEM;
retry->node = node;
retry->func = func;
retry->user = user;
list_add(&retry->link, &retry_list);
return 0;
}
/**
* ti_clk_get_reg_addr - get register address for a clock register
* @node: device node for the clock
* @index: register index from the clock node
* @reg: pointer to target register struct
*
* Builds clock register address from device tree information, and returns
* the data via the provided output pointer @reg. Returns 0 on success,
* negative error value on failure.
*/
int ti_clk_get_reg_addr(struct device_node *node, int index,
struct clk_omap_reg *reg)
{
u32 val;
int i;
for (i = 0; i < CLK_MAX_MEMMAPS; i++) {
if (clocks_node_ptr[i] == node->parent)
break;
}
if (i == CLK_MAX_MEMMAPS) {
pr_err("clk-provider not found for %pOFn!\n", node);
return -ENOENT;
}
reg->index = i;
if (of_property_read_u32_index(node, "reg", index, &val)) {
pr_err("%pOFn must have reg[%d]!\n", node, index);
return -EINVAL;
}
reg->offset = val;
reg->ptr = NULL;
return 0;
}
void ti_clk_latch(struct clk_omap_reg *reg, s8 shift)
{
u32 latch;
if (shift < 0)
return;
latch = 1 << shift;
ti_clk_ll_ops->clk_rmw(latch, latch, reg);
ti_clk_ll_ops->clk_rmw(0, latch, reg);
ti_clk_ll_ops->clk_readl(reg); /* OCP barrier */
}
/**
* omap2_clk_provider_init - init master clock provider
* @parent: master node
* @index: internal index for clk_reg_ops
* @syscon: syscon regmap pointer for accessing clock registers
* @mem: iomem pointer for the clock provider memory area, only used if
* syscon is not provided
*
* Initializes a master clock IP block. This basically sets up the
* mapping from clocks node to the memory map index. All the clocks
* are then initialized through the common of_clk_init call, and the
* clocks will access their memory maps based on the node layout.
* Returns 0 in success.
*/
int __init omap2_clk_provider_init(struct device_node *parent, int index,
struct regmap *syscon, void __iomem *mem)
{
struct device_node *clocks;
struct clk_iomap *io;
/* get clocks for this parent */
clocks = of_get_child_by_name(parent, "clocks");
if (!clocks) {
pr_err("%pOFn missing 'clocks' child node.\n", parent);
return -EINVAL;
}
/* add clocks node info */
clocks_node_ptr[index] = clocks;
io = kzalloc(sizeof(*io), GFP_KERNEL);
if (!io)
return -ENOMEM;
io->regmap = syscon;
io->mem = mem;
clk_memmaps[index] = io;
return 0;
}
/**
* omap2_clk_legacy_provider_init - initialize a legacy clock provider
* @index: index for the clock provider
* @mem: iomem pointer for the clock provider memory area
*
* Initializes a legacy clock provider memory mapping.
*/
void __init omap2_clk_legacy_provider_init(int index, void __iomem *mem)
{
struct clk_iomap *io;
io = memblock_alloc(sizeof(*io), SMP_CACHE_BYTES);
if (!io)
panic("%s: Failed to allocate %zu bytes\n", __func__,
sizeof(*io));
io->mem = mem;
clk_memmaps[index] = io;
}
/**
* ti_dt_clk_init_retry_clks - init clocks from the retry list
*
* Initializes any clocks that have failed to initialize before,
* reasons being missing parent node(s) during earlier init. This
* typically happens only for DPLLs which need to have both of their
* parent clocks ready during init.
*/
void ti_dt_clk_init_retry_clks(void)
{
struct clk_init_item *retry;
struct clk_init_item *tmp;
int retries = 5;
while (!list_empty(&retry_list) && retries) {
list_for_each_entry_safe(retry, tmp, &retry_list, link) {
pr_debug("retry-init: %pOFn\n", retry->node);
retry->func(retry->user, retry->node);
list_del(&retry->link);
kfree(retry);
}
retries--;
}
}
static const struct of_device_id simple_clk_match_table[] __initconst = {
{ .compatible = "fixed-clock" },
{ .compatible = "fixed-factor-clock" },
{ }
};
/**
* ti_clk_add_aliases - setup clock aliases
*
* Sets up any missing clock aliases. No return value.
*/
void __init ti_clk_add_aliases(void)
{
struct device_node *np;
struct clk *clk;
for_each_matching_node(np, simple_clk_match_table) {
struct of_phandle_args clkspec;
clkspec.np = np;
clk = of_clk_get_from_provider(&clkspec);
ti_clk_add_alias(NULL, clk, np->name);
}
}
/**
* ti_clk_setup_features - setup clock features flags
* @features: features definition to use
*
* Initializes the clock driver features flags based on platform
* provided data. No return value.
*/
void __init ti_clk_setup_features(struct ti_clk_features *features)
{
memcpy(&ti_clk_features, features, sizeof(*features));
}
/**
* ti_clk_get_features - get clock driver features flags
*
* Get TI clock driver features description. Returns a pointer
* to the current feature setup.
*/
const struct ti_clk_features *ti_clk_get_features(void)
{
return &ti_clk_features;
}
/**
* omap2_clk_enable_init_clocks - prepare & enable a list of clocks
* @clk_names: ptr to an array of strings of clock names to enable
* @num_clocks: number of clock names in @clk_names
*
* Prepare and enable a list of clocks, named by @clk_names. No
* return value. XXX Deprecated; only needed until these clocks are
* properly claimed and enabled by the drivers or core code that uses
* them. XXX What code disables & calls clk_put on these clocks?
*/
void omap2_clk_enable_init_clocks(const char **clk_names, u8 num_clocks)
{
struct clk *init_clk;
int i;
for (i = 0; i < num_clocks; i++) {
init_clk = clk_get(NULL, clk_names[i]);
if (WARN(IS_ERR(init_clk), "could not find init clock %s\n",
clk_names[i]))
continue;
clk_prepare_enable(init_clk);
}
}
/**
* ti_clk_add_alias - add a clock alias for a TI clock
* @dev: device alias for this clock
* @clk: clock handle to create alias for
* @con: connection ID for this clock
*
* Creates a clock alias for a TI clock. Allocates the clock lookup entry
* and assigns the data to it. Returns 0 if successful, negative error
* value otherwise.
*/
int ti_clk_add_alias(struct device *dev, struct clk *clk, const char *con)
{
struct clk_lookup *cl;
if (!clk)
return 0;
if (IS_ERR(clk))
return PTR_ERR(clk);
cl = kzalloc(sizeof(*cl), GFP_KERNEL);
if (!cl)
return -ENOMEM;
if (dev)
cl->dev_id = dev_name(dev);
cl->con_id = con;
cl->clk = clk;
clkdev_add(cl);
return 0;
}
/**
* ti_clk_register - register a TI clock to the common clock framework
* @dev: device for this clock
* @hw: hardware clock handle
* @con: connection ID for this clock
*
* Registers a TI clock to the common clock framework, and adds a clock
* alias for it. Returns a handle to the registered clock if successful,
* ERR_PTR value in failure.
*/
struct clk *ti_clk_register(struct device *dev, struct clk_hw *hw,
const char *con)
{
struct clk *clk;
int ret;
clk = clk_register(dev, hw);
if (IS_ERR(clk))
return clk;
ret = ti_clk_add_alias(dev, clk, con);
if (ret) {
clk_unregister(clk);
return ERR_PTR(ret);
}
return clk;
}
/**
* ti_clk_register_omap_hw - register a clk_hw_omap to the clock framework
* @dev: device for this clock
* @hw: hardware clock handle
* @con: connection ID for this clock
*
* Registers a clk_hw_omap clock to the clock framewor, adds a clock alias
* for it, and adds the list to the available clk_hw_omap type clocks.
* Returns a handle to the registered clock if successful, ERR_PTR value
* in failure.
*/
struct clk *ti_clk_register_omap_hw(struct device *dev, struct clk_hw *hw,
const char *con)
{
struct clk *clk;
struct clk_hw_omap *oclk;
clk = ti_clk_register(dev, hw, con);
if (IS_ERR(clk))
return clk;
oclk = to_clk_hw_omap(hw);
list_add(&oclk->node, &clk_hw_omap_clocks);
return clk;
}
/**
* omap2_clk_for_each - call function for each registered clk_hw_omap
* @fn: pointer to a callback function
*
* Call @fn for each registered clk_hw_omap, passing @hw to each
* function. @fn must return 0 for success or any other value for
* failure. If @fn returns non-zero, the iteration across clocks
* will stop and the non-zero return value will be passed to the
* caller of omap2_clk_for_each().
*/
int omap2_clk_for_each(int (*fn)(struct clk_hw_omap *hw))
{
int ret;
struct clk_hw_omap *hw;
list_for_each_entry(hw, &clk_hw_omap_clocks, node) {
ret = (*fn)(hw);
if (ret)
break;
}
return ret;
}
/**
* omap2_clk_is_hw_omap - check if the provided clk_hw is OMAP clock
* @hw: clk_hw to check if it is an omap clock or not
*
* Checks if the provided clk_hw is OMAP clock or not. Returns true if
* it is, false otherwise.
*/
bool omap2_clk_is_hw_omap(struct clk_hw *hw)
{
struct clk_hw_omap *oclk;
list_for_each_entry(oclk, &clk_hw_omap_clocks, node) {
if (&oclk->hw == hw)
return true;
}
return false;
}