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.
231 lines
6.0 KiB
231 lines
6.0 KiB
// SPDX-License-Identifier: GPL-2.0 |
|
/* |
|
* Copyright (c) 2017, Linaro Limited |
|
* Author: Georgi Djakov <[email protected]> |
|
*/ |
|
|
|
#include <linux/bitops.h> |
|
#include <linux/delay.h> |
|
#include <linux/kernel.h> |
|
#include <linux/regmap.h> |
|
|
|
#include "clk-regmap-mux-div.h" |
|
|
|
#define CMD_RCGR 0x0 |
|
#define CMD_RCGR_UPDATE BIT(0) |
|
#define CMD_RCGR_DIRTY_CFG BIT(4) |
|
#define CMD_RCGR_ROOT_OFF BIT(31) |
|
#define CFG_RCGR 0x4 |
|
|
|
#define to_clk_regmap_mux_div(_hw) \ |
|
container_of(to_clk_regmap(_hw), struct clk_regmap_mux_div, clkr) |
|
|
|
int mux_div_set_src_div(struct clk_regmap_mux_div *md, u32 src, u32 div) |
|
{ |
|
int ret, count; |
|
u32 val, mask; |
|
const char *name = clk_hw_get_name(&md->clkr.hw); |
|
|
|
val = (div << md->hid_shift) | (src << md->src_shift); |
|
mask = ((BIT(md->hid_width) - 1) << md->hid_shift) | |
|
((BIT(md->src_width) - 1) << md->src_shift); |
|
|
|
ret = regmap_update_bits(md->clkr.regmap, CFG_RCGR + md->reg_offset, |
|
mask, val); |
|
if (ret) |
|
return ret; |
|
|
|
ret = regmap_update_bits(md->clkr.regmap, CMD_RCGR + md->reg_offset, |
|
CMD_RCGR_UPDATE, CMD_RCGR_UPDATE); |
|
if (ret) |
|
return ret; |
|
|
|
/* Wait for update to take effect */ |
|
for (count = 500; count > 0; count--) { |
|
ret = regmap_read(md->clkr.regmap, CMD_RCGR + md->reg_offset, |
|
&val); |
|
if (ret) |
|
return ret; |
|
if (!(val & CMD_RCGR_UPDATE)) |
|
return 0; |
|
udelay(1); |
|
} |
|
|
|
pr_err("%s: RCG did not update its configuration", name); |
|
return -EBUSY; |
|
} |
|
EXPORT_SYMBOL_GPL(mux_div_set_src_div); |
|
|
|
static void mux_div_get_src_div(struct clk_regmap_mux_div *md, u32 *src, |
|
u32 *div) |
|
{ |
|
u32 val, d, s; |
|
const char *name = clk_hw_get_name(&md->clkr.hw); |
|
|
|
regmap_read(md->clkr.regmap, CMD_RCGR + md->reg_offset, &val); |
|
|
|
if (val & CMD_RCGR_DIRTY_CFG) { |
|
pr_err("%s: RCG configuration is pending\n", name); |
|
return; |
|
} |
|
|
|
regmap_read(md->clkr.regmap, CFG_RCGR + md->reg_offset, &val); |
|
s = (val >> md->src_shift); |
|
s &= BIT(md->src_width) - 1; |
|
*src = s; |
|
|
|
d = (val >> md->hid_shift); |
|
d &= BIT(md->hid_width) - 1; |
|
*div = d; |
|
} |
|
|
|
static inline bool is_better_rate(unsigned long req, unsigned long best, |
|
unsigned long new) |
|
{ |
|
return (req <= new && new < best) || (best < req && best < new); |
|
} |
|
|
|
static int mux_div_determine_rate(struct clk_hw *hw, |
|
struct clk_rate_request *req) |
|
{ |
|
struct clk_regmap_mux_div *md = to_clk_regmap_mux_div(hw); |
|
unsigned int i, div, max_div; |
|
unsigned long actual_rate, best_rate = 0; |
|
unsigned long req_rate = req->rate; |
|
|
|
for (i = 0; i < clk_hw_get_num_parents(hw); i++) { |
|
struct clk_hw *parent = clk_hw_get_parent_by_index(hw, i); |
|
unsigned long parent_rate = clk_hw_get_rate(parent); |
|
|
|
max_div = BIT(md->hid_width) - 1; |
|
for (div = 1; div < max_div; div++) { |
|
parent_rate = mult_frac(req_rate, div, 2); |
|
parent_rate = clk_hw_round_rate(parent, parent_rate); |
|
actual_rate = mult_frac(parent_rate, 2, div); |
|
|
|
if (is_better_rate(req_rate, best_rate, actual_rate)) { |
|
best_rate = actual_rate; |
|
req->rate = best_rate; |
|
req->best_parent_rate = parent_rate; |
|
req->best_parent_hw = parent; |
|
} |
|
|
|
if (actual_rate < req_rate || best_rate <= req_rate) |
|
break; |
|
} |
|
} |
|
|
|
if (!best_rate) |
|
return -EINVAL; |
|
|
|
return 0; |
|
} |
|
|
|
static int __mux_div_set_rate_and_parent(struct clk_hw *hw, unsigned long rate, |
|
unsigned long prate, u32 src) |
|
{ |
|
struct clk_regmap_mux_div *md = to_clk_regmap_mux_div(hw); |
|
int ret; |
|
u32 div, max_div, best_src = 0, best_div = 0; |
|
unsigned int i; |
|
unsigned long actual_rate, best_rate = 0; |
|
|
|
for (i = 0; i < clk_hw_get_num_parents(hw); i++) { |
|
struct clk_hw *parent = clk_hw_get_parent_by_index(hw, i); |
|
unsigned long parent_rate = clk_hw_get_rate(parent); |
|
|
|
max_div = BIT(md->hid_width) - 1; |
|
for (div = 1; div < max_div; div++) { |
|
parent_rate = mult_frac(rate, div, 2); |
|
parent_rate = clk_hw_round_rate(parent, parent_rate); |
|
actual_rate = mult_frac(parent_rate, 2, div); |
|
|
|
if (is_better_rate(rate, best_rate, actual_rate)) { |
|
best_rate = actual_rate; |
|
best_src = md->parent_map[i]; |
|
best_div = div - 1; |
|
} |
|
|
|
if (actual_rate < rate || best_rate <= rate) |
|
break; |
|
} |
|
} |
|
|
|
ret = mux_div_set_src_div(md, best_src, best_div); |
|
if (!ret) { |
|
md->div = best_div; |
|
md->src = best_src; |
|
} |
|
|
|
return ret; |
|
} |
|
|
|
static u8 mux_div_get_parent(struct clk_hw *hw) |
|
{ |
|
struct clk_regmap_mux_div *md = to_clk_regmap_mux_div(hw); |
|
const char *name = clk_hw_get_name(hw); |
|
u32 i, div, src = 0; |
|
|
|
mux_div_get_src_div(md, &src, &div); |
|
|
|
for (i = 0; i < clk_hw_get_num_parents(hw); i++) |
|
if (src == md->parent_map[i]) |
|
return i; |
|
|
|
pr_err("%s: Can't find parent with src %d\n", name, src); |
|
return 0; |
|
} |
|
|
|
static int mux_div_set_parent(struct clk_hw *hw, u8 index) |
|
{ |
|
struct clk_regmap_mux_div *md = to_clk_regmap_mux_div(hw); |
|
|
|
return mux_div_set_src_div(md, md->parent_map[index], md->div); |
|
} |
|
|
|
static int mux_div_set_rate(struct clk_hw *hw, |
|
unsigned long rate, unsigned long prate) |
|
{ |
|
struct clk_regmap_mux_div *md = to_clk_regmap_mux_div(hw); |
|
|
|
return __mux_div_set_rate_and_parent(hw, rate, prate, md->src); |
|
} |
|
|
|
static int mux_div_set_rate_and_parent(struct clk_hw *hw, unsigned long rate, |
|
unsigned long prate, u8 index) |
|
{ |
|
struct clk_regmap_mux_div *md = to_clk_regmap_mux_div(hw); |
|
|
|
return __mux_div_set_rate_and_parent(hw, rate, prate, |
|
md->parent_map[index]); |
|
} |
|
|
|
static unsigned long mux_div_recalc_rate(struct clk_hw *hw, unsigned long prate) |
|
{ |
|
struct clk_regmap_mux_div *md = to_clk_regmap_mux_div(hw); |
|
u32 div, src; |
|
int i, num_parents = clk_hw_get_num_parents(hw); |
|
const char *name = clk_hw_get_name(hw); |
|
|
|
mux_div_get_src_div(md, &src, &div); |
|
for (i = 0; i < num_parents; i++) |
|
if (src == md->parent_map[i]) { |
|
struct clk_hw *p = clk_hw_get_parent_by_index(hw, i); |
|
unsigned long parent_rate = clk_hw_get_rate(p); |
|
|
|
return mult_frac(parent_rate, 2, div + 1); |
|
} |
|
|
|
pr_err("%s: Can't find parent %d\n", name, src); |
|
return 0; |
|
} |
|
|
|
const struct clk_ops clk_regmap_mux_div_ops = { |
|
.get_parent = mux_div_get_parent, |
|
.set_parent = mux_div_set_parent, |
|
.set_rate = mux_div_set_rate, |
|
.set_rate_and_parent = mux_div_set_rate_and_parent, |
|
.determine_rate = mux_div_determine_rate, |
|
.recalc_rate = mux_div_recalc_rate, |
|
}; |
|
EXPORT_SYMBOL_GPL(clk_regmap_mux_div_ops);
|
|
|