| /* |
| * 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/bug.h> |
| #include <linux/delay.h> |
| #include <linux/export.h> |
| #include <linux/clk-provider.h> |
| #include <linux/regmap.h> |
| |
| #include <asm/div64.h> |
| |
| #include "clk-pll.h" |
| |
| #define PLL_OUTCTRL BIT(0) |
| #define PLL_BYPASSNL BIT(1) |
| #define PLL_RESET_N BIT(2) |
| #define PLL_LOCK_COUNT_SHIFT 8 |
| #define PLL_LOCK_COUNT_MASK 0x3f |
| #define PLL_BIAS_COUNT_SHIFT 14 |
| #define PLL_BIAS_COUNT_MASK 0x3f |
| #define PLL_VOTE_FSM_ENA BIT(20) |
| #define PLL_VOTE_FSM_RESET BIT(21) |
| |
| static int clk_pll_enable(struct clk_hw *hw) |
| { |
| struct clk_pll *pll = to_clk_pll(hw); |
| int ret; |
| u32 mask, val; |
| |
| mask = PLL_OUTCTRL | PLL_RESET_N | PLL_BYPASSNL; |
| ret = regmap_read(pll->clkr.regmap, pll->mode_reg, &val); |
| if (ret) |
| return ret; |
| |
| /* Skip if already enabled or in FSM mode */ |
| if ((val & mask) == mask || val & PLL_VOTE_FSM_ENA) |
| return 0; |
| |
| /* Disable PLL bypass mode. */ |
| ret = regmap_update_bits(pll->clkr.regmap, pll->mode_reg, PLL_BYPASSNL, |
| PLL_BYPASSNL); |
| if (ret) |
| return ret; |
| |
| /* |
| * H/W requires a 5us delay between disabling the bypass and |
| * de-asserting the reset. Delay 10us just to be safe. |
| */ |
| udelay(10); |
| |
| /* De-assert active-low PLL reset. */ |
| ret = regmap_update_bits(pll->clkr.regmap, pll->mode_reg, PLL_RESET_N, |
| PLL_RESET_N); |
| if (ret) |
| return ret; |
| |
| /* Wait until PLL is locked. */ |
| udelay(50); |
| |
| /* Enable PLL output. */ |
| return regmap_update_bits(pll->clkr.regmap, pll->mode_reg, PLL_OUTCTRL, |
| PLL_OUTCTRL); |
| } |
| |
| static void clk_pll_disable(struct clk_hw *hw) |
| { |
| struct clk_pll *pll = to_clk_pll(hw); |
| u32 mask; |
| u32 val; |
| |
| regmap_read(pll->clkr.regmap, pll->mode_reg, &val); |
| /* Skip if in FSM mode */ |
| if (val & PLL_VOTE_FSM_ENA) |
| return; |
| mask = PLL_OUTCTRL | PLL_RESET_N | PLL_BYPASSNL; |
| regmap_update_bits(pll->clkr.regmap, pll->mode_reg, mask, 0); |
| } |
| |
| static unsigned long |
| clk_pll_recalc_rate(struct clk_hw *hw, unsigned long parent_rate) |
| { |
| struct clk_pll *pll = to_clk_pll(hw); |
| u32 l, m, n, config; |
| unsigned long rate; |
| u64 tmp; |
| |
| regmap_read(pll->clkr.regmap, pll->l_reg, &l); |
| regmap_read(pll->clkr.regmap, pll->m_reg, &m); |
| regmap_read(pll->clkr.regmap, pll->n_reg, &n); |
| |
| l &= 0x3ff; |
| m &= 0x7ffff; |
| n &= 0x7ffff; |
| |
| rate = parent_rate * l; |
| if (n) { |
| tmp = parent_rate; |
| tmp *= m; |
| do_div(tmp, n); |
| rate += tmp; |
| } |
| if (pll->post_div_width) { |
| regmap_read(pll->clkr.regmap, pll->config_reg, &config); |
| config >>= pll->post_div_shift; |
| config &= BIT(pll->post_div_width) - 1; |
| rate /= config + 1; |
| } |
| |
| return rate; |
| } |
| |
| static const |
| struct pll_freq_tbl *find_freq(const struct pll_freq_tbl *f, unsigned long rate) |
| { |
| if (!f) |
| return NULL; |
| |
| for (; f->freq; f++) |
| if (rate <= f->freq) |
| return f; |
| |
| return NULL; |
| } |
| |
| static int |
| clk_pll_determine_rate(struct clk_hw *hw, struct clk_rate_request *req) |
| { |
| struct clk_pll *pll = to_clk_pll(hw); |
| const struct pll_freq_tbl *f; |
| |
| f = find_freq(pll->freq_tbl, req->rate); |
| if (!f) |
| req->rate = clk_pll_recalc_rate(hw, req->best_parent_rate); |
| else |
| req->rate = f->freq; |
| |
| return 0; |
| } |
| |
| static int |
| clk_pll_set_rate(struct clk_hw *hw, unsigned long rate, unsigned long p_rate) |
| { |
| struct clk_pll *pll = to_clk_pll(hw); |
| const struct pll_freq_tbl *f; |
| bool enabled; |
| u32 mode; |
| u32 enable_mask = PLL_OUTCTRL | PLL_BYPASSNL | PLL_RESET_N; |
| |
| f = find_freq(pll->freq_tbl, rate); |
| if (!f) |
| return -EINVAL; |
| |
| regmap_read(pll->clkr.regmap, pll->mode_reg, &mode); |
| enabled = (mode & enable_mask) == enable_mask; |
| |
| if (enabled) |
| clk_pll_disable(hw); |
| |
| regmap_update_bits(pll->clkr.regmap, pll->l_reg, 0x3ff, f->l); |
| regmap_update_bits(pll->clkr.regmap, pll->m_reg, 0x7ffff, f->m); |
| regmap_update_bits(pll->clkr.regmap, pll->n_reg, 0x7ffff, f->n); |
| regmap_write(pll->clkr.regmap, pll->config_reg, f->ibits); |
| |
| if (enabled) |
| clk_pll_enable(hw); |
| |
| return 0; |
| } |
| |
| const struct clk_ops clk_pll_ops = { |
| .enable = clk_pll_enable, |
| .disable = clk_pll_disable, |
| .recalc_rate = clk_pll_recalc_rate, |
| .determine_rate = clk_pll_determine_rate, |
| .set_rate = clk_pll_set_rate, |
| }; |
| EXPORT_SYMBOL_GPL(clk_pll_ops); |
| |
| static int wait_for_pll(struct clk_pll *pll) |
| { |
| u32 val; |
| int count; |
| int ret; |
| const char *name = clk_hw_get_name(&pll->clkr.hw); |
| |
| /* Wait for pll to enable. */ |
| for (count = 200; count > 0; count--) { |
| ret = regmap_read(pll->clkr.regmap, pll->status_reg, &val); |
| if (ret) |
| return ret; |
| if (val & BIT(pll->status_bit)) |
| return 0; |
| udelay(1); |
| } |
| |
| WARN(1, "%s didn't enable after voting for it!\n", name); |
| return -ETIMEDOUT; |
| } |
| |
| static int clk_pll_vote_enable(struct clk_hw *hw) |
| { |
| int ret; |
| struct clk_pll *p = to_clk_pll(clk_hw_get_parent(hw)); |
| |
| ret = clk_enable_regmap(hw); |
| if (ret) |
| return ret; |
| |
| return wait_for_pll(p); |
| } |
| |
| const struct clk_ops clk_pll_vote_ops = { |
| .enable = clk_pll_vote_enable, |
| .disable = clk_disable_regmap, |
| }; |
| EXPORT_SYMBOL_GPL(clk_pll_vote_ops); |
| |
| static void |
| clk_pll_set_fsm_mode(struct clk_pll *pll, struct regmap *regmap, u8 lock_count) |
| { |
| u32 val; |
| u32 mask; |
| |
| /* De-assert reset to FSM */ |
| regmap_update_bits(regmap, pll->mode_reg, PLL_VOTE_FSM_RESET, 0); |
| |
| /* Program bias count and lock count */ |
| val = 1 << PLL_BIAS_COUNT_SHIFT | lock_count << PLL_LOCK_COUNT_SHIFT; |
| mask = PLL_BIAS_COUNT_MASK << PLL_BIAS_COUNT_SHIFT; |
| mask |= PLL_LOCK_COUNT_MASK << PLL_LOCK_COUNT_SHIFT; |
| regmap_update_bits(regmap, pll->mode_reg, mask, val); |
| |
| /* Enable PLL FSM voting */ |
| regmap_update_bits(regmap, pll->mode_reg, PLL_VOTE_FSM_ENA, |
| PLL_VOTE_FSM_ENA); |
| } |
| |
| static void clk_pll_configure(struct clk_pll *pll, struct regmap *regmap, |
| const struct pll_config *config) |
| { |
| u32 val; |
| u32 mask; |
| |
| regmap_write(regmap, pll->l_reg, config->l); |
| regmap_write(regmap, pll->m_reg, config->m); |
| regmap_write(regmap, pll->n_reg, config->n); |
| |
| val = config->vco_val; |
| val |= config->pre_div_val; |
| val |= config->post_div_val; |
| val |= config->mn_ena_mask; |
| val |= config->main_output_mask; |
| val |= config->aux_output_mask; |
| |
| mask = config->vco_mask; |
| mask |= config->pre_div_mask; |
| mask |= config->post_div_mask; |
| mask |= config->mn_ena_mask; |
| mask |= config->main_output_mask; |
| mask |= config->aux_output_mask; |
| |
| regmap_update_bits(regmap, pll->config_reg, mask, val); |
| } |
| |
| void clk_pll_configure_sr(struct clk_pll *pll, struct regmap *regmap, |
| const struct pll_config *config, bool fsm_mode) |
| { |
| clk_pll_configure(pll, regmap, config); |
| if (fsm_mode) |
| clk_pll_set_fsm_mode(pll, regmap, 8); |
| } |
| EXPORT_SYMBOL_GPL(clk_pll_configure_sr); |
| |
| void clk_pll_configure_sr_hpm_lp(struct clk_pll *pll, struct regmap *regmap, |
| const struct pll_config *config, bool fsm_mode) |
| { |
| clk_pll_configure(pll, regmap, config); |
| if (fsm_mode) |
| clk_pll_set_fsm_mode(pll, regmap, 0); |
| } |
| EXPORT_SYMBOL_GPL(clk_pll_configure_sr_hpm_lp); |
| |
| static int clk_pll_sr2_enable(struct clk_hw *hw) |
| { |
| struct clk_pll *pll = to_clk_pll(hw); |
| int ret; |
| u32 mode; |
| |
| ret = regmap_read(pll->clkr.regmap, pll->mode_reg, &mode); |
| if (ret) |
| return ret; |
| |
| /* Disable PLL bypass mode. */ |
| ret = regmap_update_bits(pll->clkr.regmap, pll->mode_reg, PLL_BYPASSNL, |
| PLL_BYPASSNL); |
| if (ret) |
| return ret; |
| |
| /* |
| * H/W requires a 5us delay between disabling the bypass and |
| * de-asserting the reset. Delay 10us just to be safe. |
| */ |
| udelay(10); |
| |
| /* De-assert active-low PLL reset. */ |
| ret = regmap_update_bits(pll->clkr.regmap, pll->mode_reg, PLL_RESET_N, |
| PLL_RESET_N); |
| if (ret) |
| return ret; |
| |
| ret = wait_for_pll(pll); |
| if (ret) |
| return ret; |
| |
| /* Enable PLL output. */ |
| return regmap_update_bits(pll->clkr.regmap, pll->mode_reg, PLL_OUTCTRL, |
| PLL_OUTCTRL); |
| } |
| |
| static int |
| clk_pll_sr2_set_rate(struct clk_hw *hw, unsigned long rate, unsigned long prate) |
| { |
| struct clk_pll *pll = to_clk_pll(hw); |
| const struct pll_freq_tbl *f; |
| bool enabled; |
| u32 mode; |
| u32 enable_mask = PLL_OUTCTRL | PLL_BYPASSNL | PLL_RESET_N; |
| |
| f = find_freq(pll->freq_tbl, rate); |
| if (!f) |
| return -EINVAL; |
| |
| regmap_read(pll->clkr.regmap, pll->mode_reg, &mode); |
| enabled = (mode & enable_mask) == enable_mask; |
| |
| if (enabled) |
| clk_pll_disable(hw); |
| |
| regmap_update_bits(pll->clkr.regmap, pll->l_reg, 0x3ff, f->l); |
| regmap_update_bits(pll->clkr.regmap, pll->m_reg, 0x7ffff, f->m); |
| regmap_update_bits(pll->clkr.regmap, pll->n_reg, 0x7ffff, f->n); |
| |
| if (enabled) |
| clk_pll_sr2_enable(hw); |
| |
| return 0; |
| } |
| |
| const struct clk_ops clk_pll_sr2_ops = { |
| .enable = clk_pll_sr2_enable, |
| .disable = clk_pll_disable, |
| .set_rate = clk_pll_sr2_set_rate, |
| .recalc_rate = clk_pll_recalc_rate, |
| .determine_rate = clk_pll_determine_rate, |
| }; |
| EXPORT_SYMBOL_GPL(clk_pll_sr2_ops); |