diff options
Diffstat (limited to 'drivers/clk/mmp/clk-mix.c')
| -rw-r--r-- | drivers/clk/mmp/clk-mix.c | 507 |
1 files changed, 507 insertions, 0 deletions
diff --git a/drivers/clk/mmp/clk-mix.c b/drivers/clk/mmp/clk-mix.c new file mode 100644 index 000000000..90814b261 --- /dev/null +++ b/drivers/clk/mmp/clk-mix.c @@ -0,0 +1,507 @@ +/* + * mmp mix(div and mux) clock operation source file + * + * Copyright (C) 2014 Marvell + * Chao Xie <chao.xie@marvell.com> + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + */ + +#include <linux/clk-provider.h> +#include <linux/slab.h> +#include <linux/io.h> +#include <linux/err.h> + +#include "clk.h" + +/* + * The mix clock is a clock combined mux and div type clock. + * Because the div field and mux field need to be set at same + * time, we can not divide it into 2 types of clock + */ + +#define to_clk_mix(hw) container_of(hw, struct mmp_clk_mix, hw) + +static unsigned int _get_maxdiv(struct mmp_clk_mix *mix) +{ + unsigned int div_mask = (1 << mix->reg_info.width_div) - 1; + unsigned int maxdiv = 0; + struct clk_div_table *clkt; + + if (mix->div_flags & CLK_DIVIDER_ONE_BASED) + return div_mask; + if (mix->div_flags & CLK_DIVIDER_POWER_OF_TWO) + return 1 << div_mask; + if (mix->div_table) { + for (clkt = mix->div_table; clkt->div; clkt++) + if (clkt->div > maxdiv) + maxdiv = clkt->div; + return maxdiv; + } + return div_mask + 1; +} + +static unsigned int _get_div(struct mmp_clk_mix *mix, unsigned int val) +{ + struct clk_div_table *clkt; + + if (mix->div_flags & CLK_DIVIDER_ONE_BASED) + return val; + if (mix->div_flags & CLK_DIVIDER_POWER_OF_TWO) + return 1 << val; + if (mix->div_table) { + for (clkt = mix->div_table; clkt->div; clkt++) + if (clkt->val == val) + return clkt->div; + if (clkt->div == 0) + return 0; + } + return val + 1; +} + +static unsigned int _get_mux(struct mmp_clk_mix *mix, unsigned int val) +{ + int num_parents = clk_hw_get_num_parents(&mix->hw); + int i; + + if (mix->mux_flags & CLK_MUX_INDEX_BIT) + return ffs(val) - 1; + if (mix->mux_flags & CLK_MUX_INDEX_ONE) + return val - 1; + if (mix->mux_table) { + for (i = 0; i < num_parents; i++) + if (mix->mux_table[i] == val) + return i; + if (i == num_parents) + return 0; + } + + return val; +} +static unsigned int _get_div_val(struct mmp_clk_mix *mix, unsigned int div) +{ + struct clk_div_table *clkt; + + if (mix->div_flags & CLK_DIVIDER_ONE_BASED) + return div; + if (mix->div_flags & CLK_DIVIDER_POWER_OF_TWO) + return __ffs(div); + if (mix->div_table) { + for (clkt = mix->div_table; clkt->div; clkt++) + if (clkt->div == div) + return clkt->val; + if (clkt->div == 0) + return 0; + } + + return div - 1; +} + +static unsigned int _get_mux_val(struct mmp_clk_mix *mix, unsigned int mux) +{ + if (mix->mux_table) + return mix->mux_table[mux]; + + return mux; +} + +static void _filter_clk_table(struct mmp_clk_mix *mix, + struct mmp_clk_mix_clk_table *table, + unsigned int table_size) +{ + int i; + struct mmp_clk_mix_clk_table *item; + struct clk_hw *parent, *hw; + unsigned long parent_rate; + + hw = &mix->hw; + + for (i = 0; i < table_size; i++) { + item = &table[i]; + parent = clk_hw_get_parent_by_index(hw, item->parent_index); + parent_rate = clk_hw_get_rate(parent); + if (parent_rate % item->rate) { + item->valid = 0; + } else { + item->divisor = parent_rate / item->rate; + item->valid = 1; + } + } +} + +static int _set_rate(struct mmp_clk_mix *mix, u32 mux_val, u32 div_val, + unsigned int change_mux, unsigned int change_div) +{ + struct mmp_clk_mix_reg_info *ri = &mix->reg_info; + u8 width, shift; + u32 mux_div, fc_req; + int ret, timeout = 50; + unsigned long flags = 0; + + if (!change_mux && !change_div) + return -EINVAL; + + if (mix->lock) + spin_lock_irqsave(mix->lock, flags); + + if (mix->type == MMP_CLK_MIX_TYPE_V1 + || mix->type == MMP_CLK_MIX_TYPE_V2) + mux_div = readl(ri->reg_clk_ctrl); + else + mux_div = readl(ri->reg_clk_sel); + + if (change_div) { + width = ri->width_div; + shift = ri->shift_div; + mux_div &= ~MMP_CLK_BITS_MASK(width, shift); + mux_div |= MMP_CLK_BITS_SET_VAL(div_val, width, shift); + } + + if (change_mux) { + width = ri->width_mux; + shift = ri->shift_mux; + mux_div &= ~MMP_CLK_BITS_MASK(width, shift); + mux_div |= MMP_CLK_BITS_SET_VAL(mux_val, width, shift); + } + + if (mix->type == MMP_CLK_MIX_TYPE_V1) { + writel(mux_div, ri->reg_clk_ctrl); + } else if (mix->type == MMP_CLK_MIX_TYPE_V2) { + mux_div |= (1 << ri->bit_fc); + writel(mux_div, ri->reg_clk_ctrl); + + do { + fc_req = readl(ri->reg_clk_ctrl); + timeout--; + if (!(fc_req & (1 << ri->bit_fc))) + break; + } while (timeout); + + if (timeout == 0) { + pr_err("%s:%s cannot do frequency change\n", + __func__, clk_hw_get_name(&mix->hw)); + ret = -EBUSY; + goto error; + } + } else { + fc_req = readl(ri->reg_clk_ctrl); + fc_req |= 1 << ri->bit_fc; + writel(fc_req, ri->reg_clk_ctrl); + writel(mux_div, ri->reg_clk_sel); + fc_req &= ~(1 << ri->bit_fc); + } + + ret = 0; +error: + if (mix->lock) + spin_unlock_irqrestore(mix->lock, flags); + + return ret; +} + +static int mmp_clk_mix_determine_rate(struct clk_hw *hw, + struct clk_rate_request *req) +{ + struct mmp_clk_mix *mix = to_clk_mix(hw); + struct mmp_clk_mix_clk_table *item; + struct clk_hw *parent, *parent_best; + unsigned long parent_rate, mix_rate, mix_rate_best, parent_rate_best; + unsigned long gap, gap_best; + u32 div_val_max; + unsigned int div; + int i, j; + + + mix_rate_best = 0; + parent_rate_best = 0; + gap_best = ULONG_MAX; + parent_best = NULL; + + if (mix->table) { + for (i = 0; i < mix->table_size; i++) { + item = &mix->table[i]; + if (item->valid == 0) + continue; + parent = clk_hw_get_parent_by_index(hw, + item->parent_index); + parent_rate = clk_hw_get_rate(parent); + mix_rate = parent_rate / item->divisor; + gap = abs(mix_rate - req->rate); + if (!parent_best || gap < gap_best) { + parent_best = parent; + parent_rate_best = parent_rate; + mix_rate_best = mix_rate; + gap_best = gap; + if (gap_best == 0) + goto found; + } + } + } else { + for (i = 0; i < clk_hw_get_num_parents(hw); i++) { + parent = clk_hw_get_parent_by_index(hw, i); + parent_rate = clk_hw_get_rate(parent); + div_val_max = _get_maxdiv(mix); + for (j = 0; j < div_val_max; j++) { + div = _get_div(mix, j); + mix_rate = parent_rate / div; + gap = abs(mix_rate - req->rate); + if (!parent_best || gap < gap_best) { + parent_best = parent; + parent_rate_best = parent_rate; + mix_rate_best = mix_rate; + gap_best = gap; + if (gap_best == 0) + goto found; + } + } + } + } + +found: + if (!parent_best) + return -EINVAL; + + req->best_parent_rate = parent_rate_best; + req->best_parent_hw = parent_best; + req->rate = mix_rate_best; + + return 0; +} + +static int mmp_clk_mix_set_rate_and_parent(struct clk_hw *hw, + unsigned long rate, + unsigned long parent_rate, + u8 index) +{ + struct mmp_clk_mix *mix = to_clk_mix(hw); + unsigned int div; + u32 div_val, mux_val; + + div = parent_rate / rate; + div_val = _get_div_val(mix, div); + mux_val = _get_mux_val(mix, index); + + return _set_rate(mix, mux_val, div_val, 1, 1); +} + +static u8 mmp_clk_mix_get_parent(struct clk_hw *hw) +{ + struct mmp_clk_mix *mix = to_clk_mix(hw); + struct mmp_clk_mix_reg_info *ri = &mix->reg_info; + unsigned long flags = 0; + u32 mux_div = 0; + u8 width, shift; + u32 mux_val; + + if (mix->lock) + spin_lock_irqsave(mix->lock, flags); + + if (mix->type == MMP_CLK_MIX_TYPE_V1 + || mix->type == MMP_CLK_MIX_TYPE_V2) + mux_div = readl(ri->reg_clk_ctrl); + else + mux_div = readl(ri->reg_clk_sel); + + if (mix->lock) + spin_unlock_irqrestore(mix->lock, flags); + + width = mix->reg_info.width_mux; + shift = mix->reg_info.shift_mux; + + mux_val = MMP_CLK_BITS_GET_VAL(mux_div, width, shift); + + return _get_mux(mix, mux_val); +} + +static unsigned long mmp_clk_mix_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct mmp_clk_mix *mix = to_clk_mix(hw); + struct mmp_clk_mix_reg_info *ri = &mix->reg_info; + unsigned long flags = 0; + u32 mux_div = 0; + u8 width, shift; + unsigned int div; + + if (mix->lock) + spin_lock_irqsave(mix->lock, flags); + + if (mix->type == MMP_CLK_MIX_TYPE_V1 + || mix->type == MMP_CLK_MIX_TYPE_V2) + mux_div = readl(ri->reg_clk_ctrl); + else + mux_div = readl(ri->reg_clk_sel); + + if (mix->lock) + spin_unlock_irqrestore(mix->lock, flags); + + width = mix->reg_info.width_div; + shift = mix->reg_info.shift_div; + + div = _get_div(mix, MMP_CLK_BITS_GET_VAL(mux_div, width, shift)); + + return parent_rate / div; +} + +static int mmp_clk_set_parent(struct clk_hw *hw, u8 index) +{ + struct mmp_clk_mix *mix = to_clk_mix(hw); + struct mmp_clk_mix_clk_table *item; + int i; + u32 div_val, mux_val; + + if (mix->table) { + for (i = 0; i < mix->table_size; i++) { + item = &mix->table[i]; + if (item->valid == 0) + continue; + if (item->parent_index == index) + break; + } + if (i < mix->table_size) { + div_val = _get_div_val(mix, item->divisor); + mux_val = _get_mux_val(mix, item->parent_index); + } else + return -EINVAL; + } else { + mux_val = _get_mux_val(mix, index); + div_val = 0; + } + + return _set_rate(mix, mux_val, div_val, 1, div_val ? 1 : 0); +} + +static int mmp_clk_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long best_parent_rate) +{ + struct mmp_clk_mix *mix = to_clk_mix(hw); + struct mmp_clk_mix_clk_table *item; + unsigned long parent_rate; + unsigned int best_divisor; + struct clk_hw *parent; + int i; + + best_divisor = best_parent_rate / rate; + + if (mix->table) { + for (i = 0; i < mix->table_size; i++) { + item = &mix->table[i]; + if (item->valid == 0) + continue; + parent = clk_hw_get_parent_by_index(hw, + item->parent_index); + parent_rate = clk_hw_get_rate(parent); + if (parent_rate == best_parent_rate + && item->divisor == best_divisor) + break; + } + if (i < mix->table_size) + return _set_rate(mix, + _get_mux_val(mix, item->parent_index), + _get_div_val(mix, item->divisor), + 1, 1); + else + return -EINVAL; + } else { + for (i = 0; i < clk_hw_get_num_parents(hw); i++) { + parent = clk_hw_get_parent_by_index(hw, i); + parent_rate = clk_hw_get_rate(parent); + if (parent_rate == best_parent_rate) + break; + } + if (i < clk_hw_get_num_parents(hw)) + return _set_rate(mix, _get_mux_val(mix, i), + _get_div_val(mix, best_divisor), 1, 1); + else + return -EINVAL; + } +} + +static void mmp_clk_mix_init(struct clk_hw *hw) +{ + struct mmp_clk_mix *mix = to_clk_mix(hw); + + if (mix->table) + _filter_clk_table(mix, mix->table, mix->table_size); +} + +const struct clk_ops mmp_clk_mix_ops = { + .determine_rate = mmp_clk_mix_determine_rate, + .set_rate_and_parent = mmp_clk_mix_set_rate_and_parent, + .set_rate = mmp_clk_set_rate, + .set_parent = mmp_clk_set_parent, + .get_parent = mmp_clk_mix_get_parent, + .recalc_rate = mmp_clk_mix_recalc_rate, + .init = mmp_clk_mix_init, +}; + +struct clk *mmp_clk_register_mix(struct device *dev, + const char *name, + const char **parent_names, + u8 num_parents, + unsigned long flags, + struct mmp_clk_mix_config *config, + spinlock_t *lock) +{ + struct mmp_clk_mix *mix; + struct clk *clk; + struct clk_init_data init; + size_t table_bytes; + + mix = kzalloc(sizeof(*mix), GFP_KERNEL); + if (!mix) + return ERR_PTR(-ENOMEM); + + init.name = name; + init.flags = flags | CLK_GET_RATE_NOCACHE; + init.parent_names = parent_names; + init.num_parents = num_parents; + init.ops = &mmp_clk_mix_ops; + + memcpy(&mix->reg_info, &config->reg_info, sizeof(config->reg_info)); + if (config->table) { + table_bytes = sizeof(*config->table) * config->table_size; + mix->table = kmemdup(config->table, table_bytes, GFP_KERNEL); + if (!mix->table) + goto free_mix; + + mix->table_size = config->table_size; + } + + if (config->mux_table) { + table_bytes = sizeof(u32) * num_parents; + mix->mux_table = kmemdup(config->mux_table, table_bytes, + GFP_KERNEL); + if (!mix->mux_table) { + kfree(mix->table); + goto free_mix; + } + } + + mix->div_flags = config->div_flags; + mix->mux_flags = config->mux_flags; + mix->lock = lock; + mix->hw.init = &init; + + if (config->reg_info.bit_fc >= 32) + mix->type = MMP_CLK_MIX_TYPE_V1; + else if (config->reg_info.reg_clk_sel) + mix->type = MMP_CLK_MIX_TYPE_V3; + else + mix->type = MMP_CLK_MIX_TYPE_V2; + clk = clk_register(dev, &mix->hw); + + if (IS_ERR(clk)) { + kfree(mix->mux_table); + kfree(mix->table); + kfree(mix); + } + + return clk; + +free_mix: + kfree(mix); + return ERR_PTR(-ENOMEM); +} |