160 lines
3.8 KiB
C
160 lines
3.8 KiB
C
![]() |
/*
|
||
|
* Copyright (c) 2013, The Linux Foundation. All rights reserved.
|
||
|
*
|
||
|
* This software is licensed under the terms of the GNU General Public
|
||
|
* License version 2, as published by the Free Software Foundation, and
|
||
|
* may be copied, distributed, and modified under those terms.
|
||
|
*
|
||
|
* 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/kernel.h>
|
||
|
#include <linux/bitops.h>
|
||
|
#include <linux/err.h>
|
||
|
#include <linux/delay.h>
|
||
|
#include <linux/export.h>
|
||
|
#include <linux/clk-provider.h>
|
||
|
#include <linux/regmap.h>
|
||
|
|
||
|
#include "clk-branch.h"
|
||
|
|
||
|
static bool clk_branch_in_hwcg_mode(const struct clk_branch *br)
|
||
|
{
|
||
|
u32 val;
|
||
|
|
||
|
if (!br->hwcg_reg)
|
||
|
return 0;
|
||
|
|
||
|
regmap_read(br->clkr.regmap, br->hwcg_reg, &val);
|
||
|
|
||
|
return !!(val & BIT(br->hwcg_bit));
|
||
|
}
|
||
|
|
||
|
static bool clk_branch_check_halt(const struct clk_branch *br, bool enabling)
|
||
|
{
|
||
|
bool invert = (br->halt_check == BRANCH_HALT_ENABLE);
|
||
|
u32 val;
|
||
|
|
||
|
regmap_read(br->clkr.regmap, br->halt_reg, &val);
|
||
|
|
||
|
val &= BIT(br->halt_bit);
|
||
|
if (invert)
|
||
|
val = !val;
|
||
|
|
||
|
return !!val == !enabling;
|
||
|
}
|
||
|
|
||
|
#define BRANCH_CLK_OFF BIT(31)
|
||
|
#define BRANCH_NOC_FSM_STATUS_SHIFT 28
|
||
|
#define BRANCH_NOC_FSM_STATUS_MASK 0x7
|
||
|
#define BRANCH_NOC_FSM_STATUS_ON (0x2 << BRANCH_NOC_FSM_STATUS_SHIFT)
|
||
|
|
||
|
static bool clk_branch2_check_halt(const struct clk_branch *br, bool enabling)
|
||
|
{
|
||
|
u32 val;
|
||
|
u32 mask;
|
||
|
|
||
|
mask = BRANCH_NOC_FSM_STATUS_MASK << BRANCH_NOC_FSM_STATUS_SHIFT;
|
||
|
mask |= BRANCH_CLK_OFF;
|
||
|
|
||
|
regmap_read(br->clkr.regmap, br->halt_reg, &val);
|
||
|
|
||
|
if (enabling) {
|
||
|
val &= mask;
|
||
|
return (val & BRANCH_CLK_OFF) == 0 ||
|
||
|
val == BRANCH_NOC_FSM_STATUS_ON;
|
||
|
} else {
|
||
|
return val & BRANCH_CLK_OFF;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
static int clk_branch_wait(const struct clk_branch *br, bool enabling,
|
||
|
bool (check_halt)(const struct clk_branch *, bool))
|
||
|
{
|
||
|
bool voted = br->halt_check & BRANCH_VOTED;
|
||
|
const char *name = __clk_get_name(br->clkr.hw.clk);
|
||
|
|
||
|
/* Skip checking halt bit if the clock is in hardware gated mode */
|
||
|
if (clk_branch_in_hwcg_mode(br))
|
||
|
return 0;
|
||
|
|
||
|
if (br->halt_check == BRANCH_HALT_DELAY || (!enabling && voted)) {
|
||
|
udelay(10);
|
||
|
} else if (br->halt_check == BRANCH_HALT_ENABLE ||
|
||
|
br->halt_check == BRANCH_HALT ||
|
||
|
(enabling && voted)) {
|
||
|
int count = 200;
|
||
|
|
||
|
while (count-- > 0) {
|
||
|
if (check_halt(br, enabling))
|
||
|
return 0;
|
||
|
udelay(1);
|
||
|
}
|
||
|
WARN(1, "%s status stuck at 'o%s'", name,
|
||
|
enabling ? "ff" : "n");
|
||
|
return -EBUSY;
|
||
|
}
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
static int clk_branch_toggle(struct clk_hw *hw, bool en,
|
||
|
bool (check_halt)(const struct clk_branch *, bool))
|
||
|
{
|
||
|
struct clk_branch *br = to_clk_branch(hw);
|
||
|
int ret;
|
||
|
|
||
|
if (en) {
|
||
|
ret = clk_enable_regmap(hw);
|
||
|
if (ret)
|
||
|
return ret;
|
||
|
} else {
|
||
|
clk_disable_regmap(hw);
|
||
|
}
|
||
|
|
||
|
return clk_branch_wait(br, en, check_halt);
|
||
|
}
|
||
|
|
||
|
static int clk_branch_enable(struct clk_hw *hw)
|
||
|
{
|
||
|
return clk_branch_toggle(hw, true, clk_branch_check_halt);
|
||
|
}
|
||
|
|
||
|
static void clk_branch_disable(struct clk_hw *hw)
|
||
|
{
|
||
|
clk_branch_toggle(hw, false, clk_branch_check_halt);
|
||
|
}
|
||
|
|
||
|
const struct clk_ops clk_branch_ops = {
|
||
|
.enable = clk_branch_enable,
|
||
|
.disable = clk_branch_disable,
|
||
|
.is_enabled = clk_is_enabled_regmap,
|
||
|
};
|
||
|
EXPORT_SYMBOL_GPL(clk_branch_ops);
|
||
|
|
||
|
static int clk_branch2_enable(struct clk_hw *hw)
|
||
|
{
|
||
|
return clk_branch_toggle(hw, true, clk_branch2_check_halt);
|
||
|
}
|
||
|
|
||
|
static void clk_branch2_disable(struct clk_hw *hw)
|
||
|
{
|
||
|
clk_branch_toggle(hw, false, clk_branch2_check_halt);
|
||
|
}
|
||
|
|
||
|
const struct clk_ops clk_branch2_ops = {
|
||
|
.enable = clk_branch2_enable,
|
||
|
.disable = clk_branch2_disable,
|
||
|
.is_enabled = clk_is_enabled_regmap,
|
||
|
};
|
||
|
EXPORT_SYMBOL_GPL(clk_branch2_ops);
|
||
|
|
||
|
const struct clk_ops clk_branch_simple_ops = {
|
||
|
.enable = clk_enable_regmap,
|
||
|
.disable = clk_disable_regmap,
|
||
|
.is_enabled = clk_is_enabled_regmap,
|
||
|
};
|
||
|
EXPORT_SYMBOL_GPL(clk_branch_simple_ops);
|