| /* |
| * 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/export.h> |
| #include <linux/clk-provider.h> |
| #include <linux/delay.h> |
| #include <linux/regmap.h> |
| |
| #include <asm/div64.h> |
| |
| #include "clk-rcg.h" |
| |
| #define CMD_REG 0x0 |
| #define CMD_UPDATE BIT(0) |
| #define CMD_ROOT_EN BIT(1) |
| #define CMD_DIRTY_CFG BIT(4) |
| #define CMD_DIRTY_N BIT(5) |
| #define CMD_DIRTY_M BIT(6) |
| #define CMD_DIRTY_D BIT(7) |
| #define CMD_ROOT_OFF BIT(31) |
| |
| #define CFG_REG 0x4 |
| #define CFG_SRC_DIV_SHIFT 0 |
| #define CFG_SRC_SEL_SHIFT 8 |
| #define CFG_SRC_SEL_MASK (0x7 << CFG_SRC_SEL_SHIFT) |
| #define CFG_MODE_SHIFT 12 |
| #define CFG_MODE_MASK (0x3 << CFG_MODE_SHIFT) |
| #define CFG_MODE_DUAL_EDGE (0x2 << CFG_MODE_SHIFT) |
| |
| #define M_REG 0x8 |
| #define N_REG 0xc |
| #define D_REG 0x10 |
| |
| static int clk_rcg2_is_enabled(struct clk_hw *hw) |
| { |
| struct clk_rcg2 *rcg = to_clk_rcg2(hw); |
| u32 cmd; |
| int ret; |
| |
| ret = regmap_read(rcg->clkr.regmap, rcg->cmd_rcgr + CMD_REG, &cmd); |
| if (ret) |
| return ret; |
| |
| return (cmd & CMD_ROOT_OFF) != 0; |
| } |
| |
| static u8 clk_rcg2_get_parent(struct clk_hw *hw) |
| { |
| struct clk_rcg2 *rcg = to_clk_rcg2(hw); |
| int num_parents = __clk_get_num_parents(hw->clk); |
| u32 cfg; |
| int i, ret; |
| |
| ret = regmap_read(rcg->clkr.regmap, rcg->cmd_rcgr + CFG_REG, &cfg); |
| if (ret) |
| return ret; |
| |
| cfg &= CFG_SRC_SEL_MASK; |
| cfg >>= CFG_SRC_SEL_SHIFT; |
| |
| for (i = 0; i < num_parents; i++) |
| if (cfg == rcg->parent_map[i]) |
| return i; |
| |
| return -EINVAL; |
| } |
| |
| static int update_config(struct clk_rcg2 *rcg) |
| { |
| int count, ret; |
| u32 cmd; |
| struct clk_hw *hw = &rcg->clkr.hw; |
| const char *name = __clk_get_name(hw->clk); |
| |
| ret = regmap_update_bits(rcg->clkr.regmap, rcg->cmd_rcgr + CMD_REG, |
| CMD_UPDATE, CMD_UPDATE); |
| if (ret) |
| return ret; |
| |
| /* Wait for update to take effect */ |
| for (count = 500; count > 0; count--) { |
| ret = regmap_read(rcg->clkr.regmap, rcg->cmd_rcgr + CMD_REG, &cmd); |
| if (ret) |
| return ret; |
| if (!(cmd & CMD_UPDATE)) |
| return 0; |
| udelay(1); |
| } |
| |
| WARN(1, "%s: rcg didn't update its configuration.", name); |
| return 0; |
| } |
| |
| static int clk_rcg2_set_parent(struct clk_hw *hw, u8 index) |
| { |
| struct clk_rcg2 *rcg = to_clk_rcg2(hw); |
| int ret; |
| |
| ret = regmap_update_bits(rcg->clkr.regmap, rcg->cmd_rcgr + CFG_REG, |
| CFG_SRC_SEL_MASK, |
| rcg->parent_map[index] << CFG_SRC_SEL_SHIFT); |
| if (ret) |
| return ret; |
| |
| return update_config(rcg); |
| } |
| |
| /* |
| * Calculate m/n:d rate |
| * |
| * parent_rate m |
| * rate = ----------- x --- |
| * hid_div n |
| */ |
| static unsigned long |
| calc_rate(unsigned long rate, u32 m, u32 n, u32 mode, u32 hid_div) |
| { |
| if (hid_div) { |
| rate *= 2; |
| rate /= hid_div + 1; |
| } |
| |
| if (mode) { |
| u64 tmp = rate; |
| tmp *= m; |
| do_div(tmp, n); |
| rate = tmp; |
| } |
| |
| return rate; |
| } |
| |
| static unsigned long |
| clk_rcg2_recalc_rate(struct clk_hw *hw, unsigned long parent_rate) |
| { |
| struct clk_rcg2 *rcg = to_clk_rcg2(hw); |
| u32 cfg, hid_div, m = 0, n = 0, mode = 0, mask; |
| |
| regmap_read(rcg->clkr.regmap, rcg->cmd_rcgr + CFG_REG, &cfg); |
| |
| if (rcg->mnd_width) { |
| mask = BIT(rcg->mnd_width) - 1; |
| regmap_read(rcg->clkr.regmap, rcg->cmd_rcgr + M_REG, &m); |
| m &= mask; |
| regmap_read(rcg->clkr.regmap, rcg->cmd_rcgr + N_REG, &n); |
| n = ~n; |
| n &= mask; |
| n += m; |
| mode = cfg & CFG_MODE_MASK; |
| mode >>= CFG_MODE_SHIFT; |
| } |
| |
| mask = BIT(rcg->hid_width) - 1; |
| hid_div = cfg >> CFG_SRC_DIV_SHIFT; |
| hid_div &= mask; |
| |
| return calc_rate(parent_rate, m, n, mode, hid_div); |
| } |
| |
| static const |
| struct freq_tbl *find_freq(const struct freq_tbl *f, unsigned long rate) |
| { |
| if (!f) |
| return NULL; |
| |
| for (; f->freq; f++) |
| if (rate <= f->freq) |
| return f; |
| |
| return NULL; |
| } |
| |
| static long _freq_tbl_determine_rate(struct clk_hw *hw, |
| const struct freq_tbl *f, unsigned long rate, |
| unsigned long *p_rate, struct clk **p) |
| { |
| unsigned long clk_flags; |
| |
| f = find_freq(f, rate); |
| if (!f) |
| return -EINVAL; |
| |
| clk_flags = __clk_get_flags(hw->clk); |
| *p = clk_get_parent_by_index(hw->clk, f->src); |
| if (clk_flags & CLK_SET_RATE_PARENT) { |
| if (f->pre_div) { |
| rate /= 2; |
| rate *= f->pre_div + 1; |
| } |
| |
| if (f->n) { |
| u64 tmp = rate; |
| tmp = tmp * f->n; |
| do_div(tmp, f->m); |
| rate = tmp; |
| } |
| } else { |
| rate = __clk_get_rate(*p); |
| } |
| *p_rate = rate; |
| |
| return f->freq; |
| } |
| |
| static long clk_rcg2_determine_rate(struct clk_hw *hw, unsigned long rate, |
| unsigned long *p_rate, struct clk **p) |
| { |
| struct clk_rcg2 *rcg = to_clk_rcg2(hw); |
| |
| return _freq_tbl_determine_rate(hw, rcg->freq_tbl, rate, p_rate, p); |
| } |
| |
| static int __clk_rcg2_set_rate(struct clk_hw *hw, unsigned long rate) |
| { |
| struct clk_rcg2 *rcg = to_clk_rcg2(hw); |
| const struct freq_tbl *f; |
| u32 cfg, mask; |
| int ret; |
| |
| f = find_freq(rcg->freq_tbl, rate); |
| if (!f) |
| return -EINVAL; |
| |
| if (rcg->mnd_width && f->n) { |
| mask = BIT(rcg->mnd_width) - 1; |
| ret = regmap_update_bits(rcg->clkr.regmap, rcg->cmd_rcgr + M_REG, |
| mask, f->m); |
| if (ret) |
| return ret; |
| |
| ret = regmap_update_bits(rcg->clkr.regmap, rcg->cmd_rcgr + N_REG, |
| mask, ~(f->n - f->m)); |
| if (ret) |
| return ret; |
| |
| ret = regmap_update_bits(rcg->clkr.regmap, rcg->cmd_rcgr + D_REG, |
| mask, ~f->n); |
| if (ret) |
| return ret; |
| } |
| |
| mask = BIT(rcg->hid_width) - 1; |
| mask |= CFG_SRC_SEL_MASK | CFG_MODE_MASK; |
| cfg = f->pre_div << CFG_SRC_DIV_SHIFT; |
| cfg |= rcg->parent_map[f->src] << CFG_SRC_SEL_SHIFT; |
| if (rcg->mnd_width && f->n) |
| cfg |= CFG_MODE_DUAL_EDGE; |
| ret = regmap_update_bits(rcg->clkr.regmap, rcg->cmd_rcgr + CFG_REG, mask, |
| cfg); |
| if (ret) |
| return ret; |
| |
| return update_config(rcg); |
| } |
| |
| static int clk_rcg2_set_rate(struct clk_hw *hw, unsigned long rate, |
| unsigned long parent_rate) |
| { |
| return __clk_rcg2_set_rate(hw, rate); |
| } |
| |
| static int clk_rcg2_set_rate_and_parent(struct clk_hw *hw, |
| unsigned long rate, unsigned long parent_rate, u8 index) |
| { |
| return __clk_rcg2_set_rate(hw, rate); |
| } |
| |
| const struct clk_ops clk_rcg2_ops = { |
| .is_enabled = clk_rcg2_is_enabled, |
| .get_parent = clk_rcg2_get_parent, |
| .set_parent = clk_rcg2_set_parent, |
| .recalc_rate = clk_rcg2_recalc_rate, |
| .determine_rate = clk_rcg2_determine_rate, |
| .set_rate = clk_rcg2_set_rate, |
| .set_rate_and_parent = clk_rcg2_set_rate_and_parent, |
| }; |
| EXPORT_SYMBOL_GPL(clk_rcg2_ops); |