diff options
author | Stephen Boyd <sboyd@codeaurora.org> | 2014-01-15 10:47:25 -0800 |
---|---|---|
committer | Mike Turquette <mturquette@linaro.org> | 2014-01-16 12:01:00 -0800 |
commit | bcd61c0f535a04a2aaa3f3ba27e60fae681fc88f (patch) | |
tree | 81fbb7830130ed91c207a3f088a9b5683a9f089e /drivers/clk/qcom/clk-rcg.c | |
parent | 9e2631313c463c11645db046beb9bdecaf28b62f (diff) |
clk: qcom: Add support for root clock generators (RCGs)
Add support for the root clock generators on Qualcomm devices.
RCGs are highly customizable mux/divider/counter clocks that can
be used to generate almost any rate desired given some input
source that is faster than the desired rate.
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
Diffstat (limited to 'drivers/clk/qcom/clk-rcg.c')
-rw-r--r-- | drivers/clk/qcom/clk-rcg.c | 517 |
1 files changed, 517 insertions, 0 deletions
diff --git a/drivers/clk/qcom/clk-rcg.c b/drivers/clk/qcom/clk-rcg.c new file mode 100644 index 00000000000..abfc2b675ae --- /dev/null +++ b/drivers/clk/qcom/clk-rcg.c @@ -0,0 +1,517 @@ +/* + * 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/export.h> +#include <linux/clk-provider.h> +#include <linux/regmap.h> + +#include <asm/div64.h> + +#include "clk-rcg.h" + +static u32 ns_to_src(struct src_sel *s, u32 ns) +{ + ns >>= s->src_sel_shift; + ns &= SRC_SEL_MASK; + return ns; +} + +static u32 src_to_ns(struct src_sel *s, u8 src, u32 ns) +{ + u32 mask; + + mask = SRC_SEL_MASK; + mask <<= s->src_sel_shift; + ns &= ~mask; + + ns |= src << s->src_sel_shift; + return ns; +} + +static u8 clk_rcg_get_parent(struct clk_hw *hw) +{ + struct clk_rcg *rcg = to_clk_rcg(hw); + int num_parents = __clk_get_num_parents(hw->clk); + u32 ns; + int i; + + regmap_read(rcg->clkr.regmap, rcg->ns_reg, &ns); + ns = ns_to_src(&rcg->s, ns); + for (i = 0; i < num_parents; i++) + if (ns == rcg->s.parent_map[i]) + return i; + + return -EINVAL; +} + +static int reg_to_bank(struct clk_dyn_rcg *rcg, u32 bank) +{ + bank &= BIT(rcg->mux_sel_bit); + return !!bank; +} + +static u8 clk_dyn_rcg_get_parent(struct clk_hw *hw) +{ + struct clk_dyn_rcg *rcg = to_clk_dyn_rcg(hw); + int num_parents = __clk_get_num_parents(hw->clk); + u32 ns, ctl; + int bank; + int i; + struct src_sel *s; + + regmap_read(rcg->clkr.regmap, rcg->clkr.enable_reg, &ctl); + bank = reg_to_bank(rcg, ctl); + s = &rcg->s[bank]; + + regmap_read(rcg->clkr.regmap, rcg->ns_reg, &ns); + ns = ns_to_src(s, ns); + + for (i = 0; i < num_parents; i++) + if (ns == s->parent_map[i]) + return i; + + return -EINVAL; +} + +static int clk_rcg_set_parent(struct clk_hw *hw, u8 index) +{ + struct clk_rcg *rcg = to_clk_rcg(hw); + u32 ns; + + regmap_read(rcg->clkr.regmap, rcg->ns_reg, &ns); + ns = src_to_ns(&rcg->s, rcg->s.parent_map[index], ns); + regmap_write(rcg->clkr.regmap, rcg->ns_reg, ns); + + return 0; +} + +static u32 md_to_m(struct mn *mn, u32 md) +{ + md >>= mn->m_val_shift; + md &= BIT(mn->width) - 1; + return md; +} + +static u32 ns_to_pre_div(struct pre_div *p, u32 ns) +{ + ns >>= p->pre_div_shift; + ns &= BIT(p->pre_div_width) - 1; + return ns; +} + +static u32 pre_div_to_ns(struct pre_div *p, u8 pre_div, u32 ns) +{ + u32 mask; + + mask = BIT(p->pre_div_width) - 1; + mask <<= p->pre_div_shift; + ns &= ~mask; + + ns |= pre_div << p->pre_div_shift; + return ns; +} + +static u32 mn_to_md(struct mn *mn, u32 m, u32 n, u32 md) +{ + u32 mask, mask_w; + + mask_w = BIT(mn->width) - 1; + mask = (mask_w << mn->m_val_shift) | mask_w; + md &= ~mask; + + if (n) { + m <<= mn->m_val_shift; + md |= m; + md |= ~n & mask_w; + } + + return md; +} + +static u32 ns_m_to_n(struct mn *mn, u32 ns, u32 m) +{ + ns = ~ns >> mn->n_val_shift; + ns &= BIT(mn->width) - 1; + return ns + m; +} + +static u32 reg_to_mnctr_mode(struct mn *mn, u32 val) +{ + val >>= mn->mnctr_mode_shift; + val &= MNCTR_MODE_MASK; + return val; +} + +static u32 mn_to_ns(struct mn *mn, u32 m, u32 n, u32 ns) +{ + u32 mask; + + mask = BIT(mn->width) - 1; + mask <<= mn->n_val_shift; + ns &= ~mask; + + if (n) { + n = n - m; + n = ~n; + n &= BIT(mn->width) - 1; + n <<= mn->n_val_shift; + ns |= n; + } + + return ns; +} + +static u32 mn_to_reg(struct mn *mn, u32 m, u32 n, u32 val) +{ + u32 mask; + + mask = MNCTR_MODE_MASK << mn->mnctr_mode_shift; + mask |= BIT(mn->mnctr_en_bit); + val &= ~mask; + + if (n) { + val |= BIT(mn->mnctr_en_bit); + val |= MNCTR_MODE_DUAL << mn->mnctr_mode_shift; + } + + return val; +} + +static void configure_bank(struct clk_dyn_rcg *rcg, const struct freq_tbl *f) +{ + u32 ns, md, ctl, *regp; + int bank, new_bank; + struct mn *mn; + struct pre_div *p; + struct src_sel *s; + bool enabled; + u32 md_reg; + u32 bank_reg; + bool banked_mn = !!rcg->mn[1].width; + struct clk_hw *hw = &rcg->clkr.hw; + + enabled = __clk_is_enabled(hw->clk); + + regmap_read(rcg->clkr.regmap, rcg->ns_reg, &ns); + regmap_read(rcg->clkr.regmap, rcg->clkr.enable_reg, &ctl); + + if (banked_mn) { + regp = &ctl; + bank_reg = rcg->clkr.enable_reg; + } else { + regp = &ns; + bank_reg = rcg->ns_reg; + } + + bank = reg_to_bank(rcg, *regp); + new_bank = enabled ? !bank : bank; + + if (banked_mn) { + mn = &rcg->mn[new_bank]; + md_reg = rcg->md_reg[new_bank]; + + ns |= BIT(mn->mnctr_reset_bit); + regmap_write(rcg->clkr.regmap, rcg->ns_reg, ns); + + regmap_read(rcg->clkr.regmap, md_reg, &md); + md = mn_to_md(mn, f->m, f->n, md); + regmap_write(rcg->clkr.regmap, md_reg, md); + + ns = mn_to_ns(mn, f->m, f->n, ns); + regmap_write(rcg->clkr.regmap, rcg->ns_reg, ns); + + ctl = mn_to_reg(mn, f->m, f->n, ctl); + regmap_write(rcg->clkr.regmap, rcg->clkr.enable_reg, ctl); + + ns &= ~BIT(mn->mnctr_reset_bit); + regmap_write(rcg->clkr.regmap, rcg->ns_reg, ns); + } else { + p = &rcg->p[new_bank]; + ns = pre_div_to_ns(p, f->pre_div - 1, ns); + } + + s = &rcg->s[new_bank]; + ns = src_to_ns(s, s->parent_map[f->src], ns); + regmap_write(rcg->clkr.regmap, rcg->ns_reg, ns); + + if (enabled) { + *regp ^= BIT(rcg->mux_sel_bit); + regmap_write(rcg->clkr.regmap, bank_reg, *regp); + } +} + +static int clk_dyn_rcg_set_parent(struct clk_hw *hw, u8 index) +{ + struct clk_dyn_rcg *rcg = to_clk_dyn_rcg(hw); + u32 ns, ctl, md, reg; + int bank; + struct freq_tbl f = { 0 }; + bool banked_mn = !!rcg->mn[1].width; + + regmap_read(rcg->clkr.regmap, rcg->ns_reg, &ns); + regmap_read(rcg->clkr.regmap, rcg->clkr.enable_reg, &ctl); + reg = banked_mn ? ctl : ns; + + bank = reg_to_bank(rcg, reg); + + if (banked_mn) { + regmap_read(rcg->clkr.regmap, rcg->md_reg[bank], &md); + f.m = md_to_m(&rcg->mn[bank], md); + f.n = ns_m_to_n(&rcg->mn[bank], ns, f.m); + } else { + f.pre_div = ns_to_pre_div(&rcg->p[bank], ns) + 1; + } + f.src = index; + + configure_bank(rcg, &f); + + return 0; +} + +/* + * Calculate m/n:d rate + * + * parent_rate m + * rate = ----------- x --- + * pre_div n + */ +static unsigned long +calc_rate(unsigned long rate, u32 m, u32 n, u32 mode, u32 pre_div) +{ + if (pre_div) + rate /= pre_div + 1; + + if (mode) { + u64 tmp = rate; + tmp *= m; + do_div(tmp, n); + rate = tmp; + } + + return rate; +} + +static unsigned long +clk_rcg_recalc_rate(struct clk_hw *hw, unsigned long parent_rate) +{ + struct clk_rcg *rcg = to_clk_rcg(hw); + u32 pre_div, m = 0, n = 0, ns, md, mode = 0; + struct mn *mn = &rcg->mn; + + regmap_read(rcg->clkr.regmap, rcg->ns_reg, &ns); + pre_div = ns_to_pre_div(&rcg->p, ns); + + if (rcg->mn.width) { + regmap_read(rcg->clkr.regmap, rcg->md_reg, &md); + m = md_to_m(mn, md); + n = ns_m_to_n(mn, ns, m); + /* MN counter mode is in hw.enable_reg sometimes */ + if (rcg->clkr.enable_reg != rcg->ns_reg) + regmap_read(rcg->clkr.regmap, rcg->clkr.enable_reg, &mode); + else + mode = ns; + mode = reg_to_mnctr_mode(mn, mode); + } + + return calc_rate(parent_rate, m, n, mode, pre_div); +} + +static unsigned long +clk_dyn_rcg_recalc_rate(struct clk_hw *hw, unsigned long parent_rate) +{ + struct clk_dyn_rcg *rcg = to_clk_dyn_rcg(hw); + u32 m, n, pre_div, ns, md, mode, reg; + int bank; + struct mn *mn; + bool banked_mn = !!rcg->mn[1].width; + + regmap_read(rcg->clkr.regmap, rcg->ns_reg, &ns); + + if (banked_mn) + regmap_read(rcg->clkr.regmap, rcg->clkr.enable_reg, ®); + else + reg = ns; + + bank = reg_to_bank(rcg, reg); + + if (banked_mn) { + mn = &rcg->mn[bank]; + regmap_read(rcg->clkr.regmap, rcg->md_reg[bank], &md); + m = md_to_m(mn, md); + n = ns_m_to_n(mn, ns, m); + mode = reg_to_mnctr_mode(mn, reg); + return calc_rate(parent_rate, m, n, mode, 0); + } else { + pre_div = ns_to_pre_div(&rcg->p[bank], ns); + return calc_rate(parent_rate, 0, 0, 0, pre_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) { + rate = rate * f->pre_div; + 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_rcg_determine_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *p_rate, struct clk **p) +{ + struct clk_rcg *rcg = to_clk_rcg(hw); + + return _freq_tbl_determine_rate(hw, rcg->freq_tbl, rate, p_rate, p); +} + +static long clk_dyn_rcg_determine_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *p_rate, struct clk **p) +{ + struct clk_dyn_rcg *rcg = to_clk_dyn_rcg(hw); + + return _freq_tbl_determine_rate(hw, rcg->freq_tbl, rate, p_rate, p); +} + +static int clk_rcg_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct clk_rcg *rcg = to_clk_rcg(hw); + const struct freq_tbl *f; + u32 ns, md, ctl; + struct mn *mn = &rcg->mn; + u32 mask = 0; + unsigned int reset_reg; + + f = find_freq(rcg->freq_tbl, rate); + if (!f) + return -EINVAL; + + if (rcg->mn.reset_in_cc) + reset_reg = rcg->clkr.enable_reg; + else + reset_reg = rcg->ns_reg; + + if (rcg->mn.width) { + mask = BIT(mn->mnctr_reset_bit); + regmap_update_bits(rcg->clkr.regmap, reset_reg, mask, mask); + + regmap_read(rcg->clkr.regmap, rcg->md_reg, &md); + md = mn_to_md(mn, f->m, f->n, md); + regmap_write(rcg->clkr.regmap, rcg->md_reg, md); + + regmap_read(rcg->clkr.regmap, rcg->ns_reg, &ns); + /* MN counter mode is in hw.enable_reg sometimes */ + if (rcg->clkr.enable_reg != rcg->ns_reg) { + regmap_read(rcg->clkr.regmap, rcg->clkr.enable_reg, &ctl); + ctl = mn_to_reg(mn, f->m, f->n, ctl); + regmap_write(rcg->clkr.regmap, rcg->clkr.enable_reg, ctl); + } else { + ns = mn_to_reg(mn, f->m, f->n, ns); + } + ns = mn_to_ns(mn, f->m, f->n, ns); + } else { + regmap_read(rcg->clkr.regmap, rcg->ns_reg, &ns); + } + + ns = pre_div_to_ns(&rcg->p, f->pre_div - 1, ns); + regmap_write(rcg->clkr.regmap, rcg->ns_reg, ns); + + regmap_update_bits(rcg->clkr.regmap, reset_reg, mask, 0); + + return 0; +} + +static int __clk_dyn_rcg_set_rate(struct clk_hw *hw, unsigned long rate) +{ + struct clk_dyn_rcg *rcg = to_clk_dyn_rcg(hw); + const struct freq_tbl *f; + + f = find_freq(rcg->freq_tbl, rate); + if (!f) + return -EINVAL; + + configure_bank(rcg, f); + + return 0; +} + +static int clk_dyn_rcg_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + return __clk_dyn_rcg_set_rate(hw, rate); +} + +static int clk_dyn_rcg_set_rate_and_parent(struct clk_hw *hw, + unsigned long rate, unsigned long parent_rate, u8 index) +{ + return __clk_dyn_rcg_set_rate(hw, rate); +} + +const struct clk_ops clk_rcg_ops = { + .enable = clk_enable_regmap, + .disable = clk_disable_regmap, + .get_parent = clk_rcg_get_parent, + .set_parent = clk_rcg_set_parent, + .recalc_rate = clk_rcg_recalc_rate, + .determine_rate = clk_rcg_determine_rate, + .set_rate = clk_rcg_set_rate, +}; +EXPORT_SYMBOL_GPL(clk_rcg_ops); + +const struct clk_ops clk_dyn_rcg_ops = { + .enable = clk_enable_regmap, + .is_enabled = clk_is_enabled_regmap, + .disable = clk_disable_regmap, + .get_parent = clk_dyn_rcg_get_parent, + .set_parent = clk_dyn_rcg_set_parent, + .recalc_rate = clk_dyn_rcg_recalc_rate, + .determine_rate = clk_dyn_rcg_determine_rate, + .set_rate = clk_dyn_rcg_set_rate, + .set_rate_and_parent = clk_dyn_rcg_set_rate_and_parent, +}; +EXPORT_SYMBOL_GPL(clk_dyn_rcg_ops); |