diff options
Diffstat (limited to 'drivers/clk/qcom/clk-rcg2.c')
| -rw-r--r-- | drivers/clk/qcom/clk-rcg2.c | 198 |
1 files changed, 189 insertions, 9 deletions
diff --git a/drivers/clk/qcom/clk-rcg2.c b/drivers/clk/qcom/clk-rcg2.c index bf6406f5279a..8001fd9faf9d 100644 --- a/drivers/clk/qcom/clk-rcg2.c +++ b/drivers/clk/qcom/clk-rcg2.c @@ -8,11 +8,13 @@ #include <linux/err.h> #include <linux/bug.h> #include <linux/export.h> +#include <linux/clk.h> #include <linux/clk-provider.h> #include <linux/delay.h> #include <linux/rational.h> #include <linux/regmap.h> #include <linux/math64.h> +#include <linux/gcd.h> #include <linux/minmax.h> #include <linux/slab.h> @@ -32,6 +34,7 @@ #define CFG_REG 0x4 #define CFG_SRC_DIV_SHIFT 0 +#define CFG_SRC_DIV_LENGTH 8 #define CFG_SRC_SEL_SHIFT 8 #define CFG_SRC_SEL_MASK (0x7 << CFG_SRC_SEL_SHIFT) #define CFG_MODE_SHIFT 12 @@ -148,12 +151,32 @@ static int clk_rcg2_set_parent(struct clk_hw *hw, u8 index) return update_config(rcg); } -/* - * Calculate m/n:d rate +/** + * convert_to_reg_val() - Convert divisor values to hardware values. + * + * @f: Frequency table with pure m/n/pre_div parameters. + */ +static void convert_to_reg_val(struct freq_tbl *f) +{ + f->pre_div *= 2; + f->pre_div -= 1; +} + +/** + * calc_rate() - Calculate rate based on m/n:d values + * + * @rate: Parent rate. + * @m: Multiplier. + * @n: Divisor. + * @mode: Use zero to ignore m/n calculation. + * @hid_div: Pre divisor register value. Pre divisor value + * relates to hid_div as pre_div = (hid_div + 1) / 2. + * + * Return calculated rate according to formula: * * parent_rate m * rate = ----------- x --- - * hid_div n + * pre_div n */ static unsigned long calc_rate(unsigned long rate, u32 m, u32 n, u32 mode, u32 hid_div) @@ -393,16 +416,110 @@ static int clk_rcg2_fm_determine_rate(struct clk_hw *hw, return _freq_tbl_fm_determine_rate(hw, rcg->freq_multi_tbl, req); } -static int __clk_rcg2_configure(struct clk_rcg2 *rcg, const struct freq_tbl *f, - u32 *_cfg) +/** + * clk_rcg2_split_div() - Split multiplier that doesn't fit in n neither in pre_div. + * + * @multiplier: Multiplier to split between n and pre_div. + * @pre_div: Pointer to pre divisor value. + * @n: Pointer to n divisor value. + * @pre_div_max: Pre divisor maximum value. + */ +static inline void clk_rcg2_split_div(int multiplier, unsigned int *pre_div, + u16 *n, unsigned int pre_div_max) +{ + *n = mult_frac(multiplier * *n, *pre_div, pre_div_max); + *pre_div = pre_div_max; +} + +static void clk_rcg2_calc_mnd(u64 parent_rate, u64 rate, struct freq_tbl *f, + unsigned int mnd_max, unsigned int pre_div_max) +{ + int i = 2; + unsigned int pre_div = 1; + unsigned long rates_gcd, scaled_parent_rate; + u16 m, n = 1, n_candidate = 1, n_max; + + rates_gcd = gcd(parent_rate, rate); + m = div64_u64(rate, rates_gcd); + scaled_parent_rate = div64_u64(parent_rate, rates_gcd); + while (scaled_parent_rate > (mnd_max + m) * pre_div_max) { + // we're exceeding divisor's range, trying lower scale. + if (m > 1) { + m--; + scaled_parent_rate = mult_frac(scaled_parent_rate, m, (m + 1)); + } else { + // cannot lower scale, just set max divisor values. + f->n = mnd_max + m; + f->pre_div = pre_div_max; + f->m = m; + return; + } + } + + n_max = m + mnd_max; + + while (scaled_parent_rate > 1) { + while (scaled_parent_rate % i == 0) { + n_candidate *= i; + if (n_candidate < n_max) + n = n_candidate; + else if (pre_div * i < pre_div_max) + pre_div *= i; + else + clk_rcg2_split_div(i, &pre_div, &n, pre_div_max); + + scaled_parent_rate /= i; + } + i++; + } + + f->m = m; + f->n = n; + f->pre_div = pre_div > 1 ? pre_div : 0; +} + +static int clk_rcg2_determine_gp_rate(struct clk_hw *hw, + struct clk_rate_request *req) +{ + struct clk_rcg2 *rcg = to_clk_rcg2(hw); + struct freq_tbl f_tbl = {}, *f = &f_tbl; + int mnd_max = BIT(rcg->mnd_width) - 1; + int hid_max = BIT(rcg->hid_width) - 1; + struct clk_hw *parent; + u64 parent_rate; + + parent = clk_hw_get_parent(hw); + parent_rate = clk_get_rate(parent->clk); + if (!parent_rate) + return -EINVAL; + + clk_rcg2_calc_mnd(parent_rate, req->rate, f, mnd_max, hid_max / 2); + convert_to_reg_val(f); + req->rate = calc_rate(parent_rate, f->m, f->n, f->n, f->pre_div); + + return 0; +} + +static int __clk_rcg2_configure_parent(struct clk_rcg2 *rcg, u8 src, u32 *_cfg) { - u32 cfg, mask, d_val, not2d_val, n_minus_m; struct clk_hw *hw = &rcg->clkr.hw; - int ret, index = qcom_find_src_index(hw, rcg->parent_map, f->src); + int index = qcom_find_src_index(hw, rcg->parent_map, src); if (index < 0) return index; + *_cfg &= ~CFG_SRC_SEL_MASK; + *_cfg |= rcg->parent_map[index].cfg << CFG_SRC_SEL_SHIFT; + + return 0; +} + +static int __clk_rcg2_configure_mnd(struct clk_rcg2 *rcg, const struct freq_tbl *f, + u32 *_cfg) +{ + u32 cfg, mask, d_val, not2d_val, n_minus_m; + int ret; + if (rcg->mnd_width && f->n) { mask = BIT(rcg->mnd_width) - 1; ret = regmap_update_bits(rcg->clkr.regmap, @@ -431,9 +548,8 @@ static int __clk_rcg2_configure(struct clk_rcg2 *rcg, const struct freq_tbl *f, } mask = BIT(rcg->hid_width) - 1; - mask |= CFG_SRC_SEL_MASK | CFG_MODE_MASK | CFG_HW_CLK_CTRL_MASK; + mask |= CFG_MODE_MASK | CFG_HW_CLK_CTRL_MASK; cfg = f->pre_div << CFG_SRC_DIV_SHIFT; - cfg |= rcg->parent_map[index].cfg << CFG_SRC_SEL_SHIFT; if (rcg->mnd_width && f->n && (f->m != f->n)) cfg |= CFG_MODE_DUAL_EDGE; if (rcg->hw_clk_ctrl) @@ -445,6 +561,22 @@ static int __clk_rcg2_configure(struct clk_rcg2 *rcg, const struct freq_tbl *f, return 0; } +static int __clk_rcg2_configure(struct clk_rcg2 *rcg, const struct freq_tbl *f, + u32 *_cfg) +{ + int ret; + + ret = __clk_rcg2_configure_parent(rcg, f->src, _cfg); + if (ret) + return ret; + + ret = __clk_rcg2_configure_mnd(rcg, f, _cfg); + if (ret) + return ret; + + return 0; +} + static int clk_rcg2_configure(struct clk_rcg2 *rcg, const struct freq_tbl *f) { u32 cfg; @@ -465,6 +597,26 @@ static int clk_rcg2_configure(struct clk_rcg2 *rcg, const struct freq_tbl *f) return update_config(rcg); } +static int clk_rcg2_configure_gp(struct clk_rcg2 *rcg, const struct freq_tbl *f) +{ + u32 cfg; + int ret; + + ret = regmap_read(rcg->clkr.regmap, RCG_CFG_OFFSET(rcg), &cfg); + if (ret) + return ret; + + ret = __clk_rcg2_configure_mnd(rcg, f, &cfg); + if (ret) + return ret; + + ret = regmap_write(rcg->clkr.regmap, RCG_CFG_OFFSET(rcg), cfg); + if (ret) + return ret; + + return update_config(rcg); +} + static int __clk_rcg2_set_rate(struct clk_hw *hw, unsigned long rate, enum freq_policy policy) { @@ -518,6 +670,22 @@ static int clk_rcg2_set_rate(struct clk_hw *hw, unsigned long rate, return __clk_rcg2_set_rate(hw, rate, CEIL); } +static int clk_rcg2_set_gp_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct clk_rcg2 *rcg = to_clk_rcg2(hw); + int mnd_max = BIT(rcg->mnd_width) - 1; + int hid_max = BIT(rcg->hid_width) - 1; + struct freq_tbl f_tbl = {}, *f = &f_tbl; + int ret; + + clk_rcg2_calc_mnd(parent_rate, rate, f, mnd_max, hid_max / 2); + convert_to_reg_val(f); + ret = clk_rcg2_configure_gp(rcg, f); + + return ret; +} + static int clk_rcg2_set_floor_rate(struct clk_hw *hw, unsigned long rate, unsigned long parent_rate) { @@ -645,6 +813,18 @@ const struct clk_ops clk_rcg2_ops = { }; EXPORT_SYMBOL_GPL(clk_rcg2_ops); +const struct clk_ops clk_rcg2_gp_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_gp_rate, + .set_rate = clk_rcg2_set_gp_rate, + .get_duty_cycle = clk_rcg2_get_duty_cycle, + .set_duty_cycle = clk_rcg2_set_duty_cycle, +}; +EXPORT_SYMBOL_GPL(clk_rcg2_gp_ops); + const struct clk_ops clk_rcg2_floor_ops = { .is_enabled = clk_rcg2_is_enabled, .get_parent = clk_rcg2_get_parent, |