From fd06a2cc719296f65a280cb1533b125f63cfcb34 Mon Sep 17 00:00:00 2001 From: Stephen Boyd Date: Mon, 28 Apr 2014 15:58:11 -0700 Subject: [PATCH 127/182] clk: qcom: Add support for setting rates on PLLs Some PLLs may require changing their rate at runtime. Add support for these PLLs. Signed-off-by: Stephen Boyd --- drivers/clk/qcom/clk-pll.c | 68 +++++++++++++++++++++++++++++++++++++++++++- drivers/clk/qcom/clk-pll.h | 20 +++++++++++++ 2 files changed, 87 insertions(+), 1 deletion(-) diff --git a/drivers/clk/qcom/clk-pll.c b/drivers/clk/qcom/clk-pll.c index 0f927c5..80c7a76 100644 --- a/drivers/clk/qcom/clk-pll.c +++ b/drivers/clk/qcom/clk-pll.c @@ -97,7 +97,7 @@ 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; + u32 l, m, n, config; unsigned long rate; u64 tmp; @@ -116,13 +116,79 @@ clk_pll_recalc_rate(struct clk_hw *hw, unsigned long parent_rate) 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 long +clk_pll_determine_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *p_rate, struct clk **p) +{ + struct clk_pll *pll = to_clk_pll(hw); + const struct pll_freq_tbl *f; + + f = find_freq(pll->freq_tbl, rate); + if (!f) + return clk_pll_recalc_rate(hw, *p_rate); + + return f->freq; +} + +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); diff --git a/drivers/clk/qcom/clk-pll.h b/drivers/clk/qcom/clk-pll.h index 0775a99..5f9928b 100644 --- a/drivers/clk/qcom/clk-pll.h +++ b/drivers/clk/qcom/clk-pll.h @@ -18,6 +18,21 @@ #include "clk-regmap.h" /** + * struct pll_freq_tbl - PLL frequency table + * @l: L value + * @m: M value + * @n: N value + * @ibits: internal values + */ +struct pll_freq_tbl { + unsigned long freq; + u16 l; + u16 m; + u16 n; + u32 ibits; +}; + +/** * struct clk_pll - phase locked loop (PLL) * @l_reg: L register * @m_reg: M register @@ -26,6 +41,7 @@ * @mode_reg: mode register * @status_reg: status register * @status_bit: ANDed with @status_reg to determine if PLL is enabled + * @freq_tbl: PLL frequency table * @hw: handle between common and hardware-specific interfaces */ struct clk_pll { @@ -36,6 +52,10 @@ struct clk_pll { u32 mode_reg; u32 status_reg; u8 status_bit; + u8 post_div_width; + u8 post_div_shift; + + const struct pll_freq_tbl *freq_tbl; struct clk_regmap clkr; }; -- 1.7.10.4