blob: 212071dccb4dde71a68d0463bf6503407cad71f7 [file] [log] [blame]
/*
* Copyright (C) 2009-2016 Broadcom
*
* 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 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#define pr_fmt(fmt) "clk-brcmstb: " fmt
#include <linux/io.h>
#include <linux/of.h>
#include <linux/delay.h>
#include <linux/of_address.h>
#include <linux/of_platform.h>
#include <linux/slab.h>
#include <linux/kernel.h>
#include <linux/err.h>
#include <linux/clk.h>
#include <linux/clkdev.h>
#include <linux/clk-provider.h>
#include <linux/syscore_ops.h>
#include <linux/brcmstb/brcmstb.h>
static bool shut_off_unused_clks = true;
static int bcm_full_clk = 2;
static void __iomem *cpu_clk_div_reg;
struct bcm_clk_gate {
struct clk_hw hw;
void __iomem *reg;
u8 bit_idx;
u8 flags;
u32 delay[2];
spinlock_t *lock;
struct clk_ops ops;
};
struct bcm_clk_sw {
struct clk_hw hw;
struct clk_ops ops;
};
#define to_brcmstb_clk_gate(p) container_of(p, struct bcm_clk_gate, hw)
#define to_brcmstb_clk_sw(p) container_of(p, struct bcm_clk_sw, hw)
static DEFINE_SPINLOCK(lock);
static int cpu_clk_div_pos __initdata;
static int cpu_clk_div_width __initdata;
#ifdef CONFIG_PM_SLEEP
static u32 cpu_clk_div_reg_dump;
static int brcmstb_clk_suspend(void)
{
if (cpu_clk_div_reg)
cpu_clk_div_reg_dump = __raw_readl(cpu_clk_div_reg);
return 0;
}
static void brcmstb_clk_resume(void)
{
if (cpu_clk_div_reg)
__raw_writel(cpu_clk_div_reg_dump, cpu_clk_div_reg);
}
static struct syscore_ops brcmstb_clk_syscore_ops = {
.suspend = brcmstb_clk_suspend,
.resume = brcmstb_clk_resume,
};
#endif /* CONFIG_PM_SLEEP */
static int __init parse_cpu_clk_div_dimensions(struct device_node *np)
{
struct property *prop;
const __be32 *p = NULL;
int len;
int elem_cnt;
const char *propname = "div-shift-width";
prop = of_find_property(np, propname, &len);
if (!prop) {
pr_err("%s property undefined\n", propname);
return -EINVAL;
}
elem_cnt = len / sizeof(u32);
if (elem_cnt != 2) {
pr_err("%s should have only 2 elements\n", propname);
return -EINVAL;
}
p = of_prop_next_u32(prop, p, &cpu_clk_div_pos);
of_prop_next_u32(prop, p, &cpu_clk_div_width);
return 0;
}
static struct clk_div_table *cpu_clk_div_table;
static int __init parse_cpu_clk_div_table(struct device_node *np)
{
struct property *prop;
const __be32 *p = NULL;
struct clk_div_table *cur_tbl_ptr;
int len;
int elem_cnt;
int i;
const char *propname = "div-table";
prop = of_find_property(np, propname, &len);
if (!prop) {
pr_err("%s property undefined\n", propname);
return -EINVAL;
}
elem_cnt = len / sizeof(u32);
if (elem_cnt < 2) {
pr_err("%s should have at least 2 elements\n", propname);
return -EINVAL;
}
if ((elem_cnt % 2) != 0) {
pr_err("%s should have even number of elements\n", propname);
return -EINVAL;
}
/* need room for last sentinel entry */
len += 2 * sizeof(u32);
cpu_clk_div_table = kmalloc(len, GFP_KERNEL);
if (!cpu_clk_div_table)
return -ENOMEM;
cur_tbl_ptr = cpu_clk_div_table;
for (i = 0; i < elem_cnt; i += 2) {
p = of_prop_next_u32(prop, p, &cur_tbl_ptr->val);
p = of_prop_next_u32(prop, p, &cur_tbl_ptr->div);
cur_tbl_ptr++;
}
/* last entry should be zeroed out */
cur_tbl_ptr->val = 0;
cur_tbl_ptr->div = 0;
return 0;
}
static void __init of_brcmstb_cpu_clk_div_setup(struct device_node *np)
{
struct clk *clk;
int rc;
cpu_clk_div_reg = of_iomap(np, 0);
if (!cpu_clk_div_reg) {
pr_err("unable to iomap cpu clk divider register!\n");
return;
}
rc = parse_cpu_clk_div_dimensions(np);
if (rc)
goto err;
rc = parse_cpu_clk_div_table(np);
if (rc)
goto err;
clk = clk_register_divider_table(NULL, "cpu-clk-div",
of_clk_get_parent_name(np, 0), 0,
cpu_clk_div_reg,
cpu_clk_div_pos, cpu_clk_div_width,
0, cpu_clk_div_table, &lock);
if (IS_ERR(clk))
goto err;
rc = of_clk_add_provider(np, of_clk_src_simple_get, clk);
if (rc) {
pr_err("error adding clock provider (%d)\n", rc);
goto err;
}
#ifdef CONFIG_PM_SLEEP
register_syscore_ops(&brcmstb_clk_syscore_ops);
#endif
return;
err:
kfree(cpu_clk_div_table);
cpu_clk_div_table = NULL;
if (cpu_clk_div_reg) {
iounmap(cpu_clk_div_reg);
cpu_clk_div_reg = NULL;
}
}
CLK_OF_DECLARE(brcmstb_cpu_clk_div, "brcm,brcmstb-cpu-clk-div",
of_brcmstb_cpu_clk_div_setup);
/*
* It works on following logic:
*
* For enabling clock, enable = 1
* set2dis = 1 -> clear bit -> set = 0
* set2dis = 0 -> set bit -> set = 1
*
* For disabling clock, enable = 0
* set2dis = 1 -> set bit -> set = 1
* set2dis = 0 -> clear bit -> set = 0
*
* So, result is always: enable xor set2dis.
*/
static void brcmstb_clk_gate_endisable(struct clk_hw *hw, int enable)
{
struct bcm_clk_gate *gate = to_brcmstb_clk_gate(hw);
int set = gate->flags & CLK_GATE_SET_TO_DISABLE ? 1 : 0;
unsigned long flags = 0;
u32 reg;
set ^= enable;
if (gate->lock)
spin_lock_irqsave(gate->lock, flags);
reg = readl(gate->reg);
if (set)
reg |= BIT(gate->bit_idx);
else
reg &= ~BIT(gate->bit_idx);
writel(reg, gate->reg);
if (set == 0 && gate->delay[0])
udelay(gate->delay[0]);
else if (set == 1 && gate->delay[1])
udelay(gate->delay[1]);
if (gate->lock)
spin_unlock_irqrestore(gate->lock, flags);
}
static int brcmstb_clk_gate_enable(struct clk_hw *hw)
{
brcmstb_clk_gate_endisable(hw, 1);
return 0;
}
static void brcmstb_clk_gate_disable(struct clk_hw *hw)
{
brcmstb_clk_gate_endisable(hw, 0);
}
static int brcmstb_clk_gate_is_enabled(struct clk_hw *hw)
{
u32 reg;
struct bcm_clk_gate *gate = to_brcmstb_clk_gate(hw);
reg = readl(gate->reg);
/* if a set bit disables this clk, flip it before masking */
if (gate->flags & CLK_GATE_SET_TO_DISABLE)
reg ^= BIT(gate->bit_idx);
reg &= BIT(gate->bit_idx);
return reg ? 1 : 0;
}
static const struct clk_ops brcmstb_clk_gate_ops = {
.enable = brcmstb_clk_gate_enable,
.disable = brcmstb_clk_gate_disable,
.is_enabled = brcmstb_clk_gate_is_enabled,
};
static const struct clk_ops brcmstb_clk_gate_inhib_dis_ops = {
.enable = brcmstb_clk_gate_enable,
.is_enabled = brcmstb_clk_gate_is_enabled,
};
static const struct clk_ops brcmstb_clk_gate_ro_ops = {
.is_enabled = brcmstb_clk_gate_is_enabled,
};
/**
* brcm_clk_gate_register - register a bcm gate clock with the clock framework.
* @dev: device that is registering this clock
* @name: name of this clock
* @parent_name: name of this clock's parent
* @flags: framework-specific flags for this clock
* @reg: register address to control gating of this clock
* @bit_idx: which bit in the register controls gating of this clock
* @clk_gate_flags: gate-specific flags for this clock
* @delay: usec delay in turning on, off.
* @lock: shared register lock for this clock
*/
static struct clk __init *brcm_clk_gate_register(
struct device *dev, const char *name, const char *parent_name,
unsigned long flags, void __iomem *reg, u8 bit_idx,
u8 clk_gate_flags, u32 delay[2], spinlock_t *lock,
bool read_only, bool inhibit_disable)
{
struct bcm_clk_gate *gate;
struct clk *clk;
struct clk_init_data init;
/* allocate the gate */
gate = kzalloc(sizeof(struct bcm_clk_gate), GFP_KERNEL);
if (!gate) {
pr_err("%s: could not allocate bcm gated clk\n", __func__);
return ERR_PTR(-ENOMEM);
}
init.name = name;
init.ops = inhibit_disable ? &brcmstb_clk_gate_inhib_dis_ops
: read_only ? &brcmstb_clk_gate_ro_ops : &brcmstb_clk_gate_ops;
init.parent_names = (parent_name ? &parent_name : NULL);
init.num_parents = (parent_name ? 1 : 0);
init.flags = flags | (parent_name ? 0 : CLK_IS_ROOT);
if (!shut_off_unused_clks)
init.flags |= CLK_IGNORE_UNUSED; /* FIXME */
/* struct bcm_gate assignments */
gate->reg = reg;
gate->bit_idx = bit_idx;
gate->flags = clk_gate_flags;
gate->lock = lock;
gate->delay[0] = delay[0];
gate->delay[1] = delay[1];
gate->hw.init = &init;
clk = clk_register(dev, &gate->hw);
if (IS_ERR(clk))
kfree(gate);
return clk;
}
static const struct clk_ops brcmstb_clk_sw_ops = {};
/**
* brcmstb_clk_sw_register - register a bcm gate clock with the clock framework.
* @dev: device that is registering this clock
* @name: name of this clock
* @parents: name of this clock's parents; not known by clock framework
* @num_parents: number of parents
* @flags: framework-specific flags for this clock
* @lock: shared register lock for this clock
*/
static struct clk __init *brcmstb_clk_sw_register(
struct device *dev, const char *name, const char **parent_names,
int num_parents, unsigned long flags, spinlock_t *lock)
{
struct bcm_clk_sw *sw_clk;
struct clk *clk;
struct clk_init_data init;
/* allocate the gate */
sw_clk = kzalloc(sizeof(struct bcm_clk_sw), GFP_KERNEL);
if (!sw_clk) {
pr_err("%s: could not allocate bcm sw clk\n", __func__);
return ERR_PTR(-ENOMEM);
}
init.name = name;
init.ops = &brcmstb_clk_sw_ops;
init.parent_names = parent_names;
init.num_parents = num_parents;
init.flags = flags | CLK_IS_BASIC | CLK_IS_SW;
if (!shut_off_unused_clks)
init.flags |= CLK_IGNORE_UNUSED; /* FIXME */
sw_clk->hw.init = &init;
clk = clk_register(dev, &sw_clk->hw);
if (IS_ERR(clk))
kfree(sw_clk);
return clk;
}
/**
* of_brcmstb_gate_clk_setup() - Setup function for brcmstb gate clock
*/
static void __init of_brcmstb_clk_gate_setup(struct device_node *node)
{
struct clk *clk;
const char *clk_name = node->name;
void __iomem *reg;
const char *parent_name;
u8 clk_gate_flags = 0;
u32 bit_idx = 0;
u32 delay[2] = {0, 0};
int ret;
bool read_only = false;
bool inhibit_disable = false;
of_property_read_string(node, "clock-output-names", &clk_name);
parent_name = of_clk_get_parent_name(node, 0);
if (of_property_read_u32(node, "bit-shift", &bit_idx)) {
pr_err("%s: missing bit-shift property for %s\n",
__func__, node->name);
return;
}
reg = of_iomap(node, 0);
if (!reg) {
pr_err("unable to iomap cpu clk divider register!\n");
return;
}
of_property_read_u32_array(node, "brcm,delay", delay, 2);
if (of_property_read_bool(node, "set-bit-to-disable"))
clk_gate_flags |= CLK_GATE_SET_TO_DISABLE;
if (of_property_read_bool(node, "brcm,read-only"))
read_only = true;
if (of_property_read_bool(node, "brcm,inhibit-disable"))
inhibit_disable = true;
clk = brcm_clk_gate_register(NULL, clk_name, parent_name, 0, reg,
(u8) bit_idx, clk_gate_flags, delay,
&lock, read_only, inhibit_disable);
if (!IS_ERR(clk)) {
of_clk_add_provider(node, of_clk_src_simple_get, clk);
ret = clk_register_clkdev(clk, clk_name, NULL);
if (ret)
pr_err("%s: clk device registration failed for '%s'\n",
__func__, clk_name);
}
}
CLK_OF_DECLARE(brcmstb_clk_gate, "brcm,brcmstb-gate-clk",
of_brcmstb_clk_gate_setup);
static void __init of_brcmstb_clk_sw_setup(struct device_node *node)
{
struct clk *clk;
const char *clk_name = node->name;
int num_parents;
const char **parent_names;
int ret, i;
of_property_read_string(node, "clock-output-names", &clk_name);
num_parents = of_property_count_strings(node, "clock-names");
if (num_parents < 1) {
pr_err("%s: brcm-sw-clock %s must have parent(s)\n",
__func__, node->name);
return;
}
parent_names = kzalloc((sizeof(char *) * num_parents),
GFP_KERNEL);
if (!parent_names) {
pr_err("%s: failed to alloc parent_names\n", __func__);
return;
}
for (i = 0; i < num_parents; i++)
parent_names[i] = of_clk_get_parent_name(node, i);
clk = brcmstb_clk_sw_register(NULL, clk_name, parent_names, num_parents,
0, NULL);
kfree(parent_names);
if (!IS_ERR(clk)) {
of_clk_add_provider(node, of_clk_src_simple_get, clk);
ret = clk_register_clkdev(clk, clk_name, NULL);
if (ret)
pr_err("%s: clk device registration failed for '%s'\n",
__func__, clk_name);
}
}
CLK_OF_DECLARE(brcmstb_clk_sw, "brcm,brcmstb-sw-clk",
of_brcmstb_clk_sw_setup);
static int __init _bcm_full_clk(char *str)
{
get_option(&str, &bcm_full_clk);
shut_off_unused_clks = bcm_full_clk > 1;
return 0;
}
early_param("bcm_full_clk", _bcm_full_clk);