mirror of https://github.com/Qortal/Brooklyn
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
140 lines
2.7 KiB
140 lines
2.7 KiB
// SPDX-License-Identifier: GPL-2.0-or-later |
|
/* |
|
* Copyright (C) 2013 Boris BREZILLON <[email protected]> |
|
*/ |
|
|
|
#include <linux/clk-provider.h> |
|
#include <linux/clkdev.h> |
|
#include <linux/clk/at91_pmc.h> |
|
#include <linux/of.h> |
|
#include <linux/mfd/syscon.h> |
|
#include <linux/regmap.h> |
|
|
|
#include "pmc.h" |
|
|
|
#define SYSTEM_MAX_ID 31 |
|
|
|
#define SYSTEM_MAX_NAME_SZ 32 |
|
|
|
#define to_clk_system(hw) container_of(hw, struct clk_system, hw) |
|
struct clk_system { |
|
struct clk_hw hw; |
|
struct regmap *regmap; |
|
struct at91_clk_pms pms; |
|
u8 id; |
|
}; |
|
|
|
static inline int is_pck(int id) |
|
{ |
|
return (id >= 8) && (id <= 15); |
|
} |
|
|
|
static inline bool clk_system_ready(struct regmap *regmap, int id) |
|
{ |
|
unsigned int status; |
|
|
|
regmap_read(regmap, AT91_PMC_SR, &status); |
|
|
|
return !!(status & (1 << id)); |
|
} |
|
|
|
static int clk_system_prepare(struct clk_hw *hw) |
|
{ |
|
struct clk_system *sys = to_clk_system(hw); |
|
|
|
regmap_write(sys->regmap, AT91_PMC_SCER, 1 << sys->id); |
|
|
|
if (!is_pck(sys->id)) |
|
return 0; |
|
|
|
while (!clk_system_ready(sys->regmap, sys->id)) |
|
cpu_relax(); |
|
|
|
return 0; |
|
} |
|
|
|
static void clk_system_unprepare(struct clk_hw *hw) |
|
{ |
|
struct clk_system *sys = to_clk_system(hw); |
|
|
|
regmap_write(sys->regmap, AT91_PMC_SCDR, 1 << sys->id); |
|
} |
|
|
|
static int clk_system_is_prepared(struct clk_hw *hw) |
|
{ |
|
struct clk_system *sys = to_clk_system(hw); |
|
unsigned int status; |
|
|
|
regmap_read(sys->regmap, AT91_PMC_SCSR, &status); |
|
|
|
if (!(status & (1 << sys->id))) |
|
return 0; |
|
|
|
if (!is_pck(sys->id)) |
|
return 1; |
|
|
|
regmap_read(sys->regmap, AT91_PMC_SR, &status); |
|
|
|
return !!(status & (1 << sys->id)); |
|
} |
|
|
|
static int clk_system_save_context(struct clk_hw *hw) |
|
{ |
|
struct clk_system *sys = to_clk_system(hw); |
|
|
|
sys->pms.status = clk_system_is_prepared(hw); |
|
|
|
return 0; |
|
} |
|
|
|
static void clk_system_restore_context(struct clk_hw *hw) |
|
{ |
|
struct clk_system *sys = to_clk_system(hw); |
|
|
|
if (sys->pms.status) |
|
clk_system_prepare(&sys->hw); |
|
} |
|
|
|
static const struct clk_ops system_ops = { |
|
.prepare = clk_system_prepare, |
|
.unprepare = clk_system_unprepare, |
|
.is_prepared = clk_system_is_prepared, |
|
.save_context = clk_system_save_context, |
|
.restore_context = clk_system_restore_context, |
|
}; |
|
|
|
struct clk_hw * __init |
|
at91_clk_register_system(struct regmap *regmap, const char *name, |
|
const char *parent_name, u8 id) |
|
{ |
|
struct clk_system *sys; |
|
struct clk_hw *hw; |
|
struct clk_init_data init; |
|
int ret; |
|
|
|
if (!parent_name || id > SYSTEM_MAX_ID) |
|
return ERR_PTR(-EINVAL); |
|
|
|
sys = kzalloc(sizeof(*sys), GFP_KERNEL); |
|
if (!sys) |
|
return ERR_PTR(-ENOMEM); |
|
|
|
init.name = name; |
|
init.ops = &system_ops; |
|
init.parent_names = &parent_name; |
|
init.num_parents = 1; |
|
init.flags = CLK_SET_RATE_PARENT; |
|
|
|
sys->id = id; |
|
sys->hw.init = &init; |
|
sys->regmap = regmap; |
|
|
|
hw = &sys->hw; |
|
ret = clk_hw_register(NULL, &sys->hw); |
|
if (ret) { |
|
kfree(sys); |
|
hw = ERR_PTR(ret); |
|
} |
|
|
|
return hw; |
|
}
|
|
|