diff options
Diffstat (limited to 'drivers/clk/st')
| -rw-r--r-- | drivers/clk/st/clkgen-pll.c | 194 |
1 files changed, 194 insertions, 0 deletions
diff --git a/drivers/clk/st/clkgen-pll.c b/drivers/clk/st/clkgen-pll.c index 494848e56e3c..38f6f3a9098e 100644 --- a/drivers/clk/st/clkgen-pll.c +++ b/drivers/clk/st/clkgen-pll.c @@ -44,6 +44,13 @@ DEFINE_SPINLOCK(clkgen_a9_lock); #define C32_MAX_ODFS (4) +/* + * PLL configuration register bits for PLL4600 C28 + */ +#define C28_NDIV_MASK (0xff) +#define C28_IDF_MASK (0x7) +#define C28_ODF_MASK (0x3f) + struct clkgen_pll_data { struct clkgen_field pdn_status; struct clkgen_field pdn_ctrl; @@ -68,6 +75,7 @@ static const struct clk_ops st_pll800c65_ops; static const struct clk_ops stm_pll3200c32_ops; static const struct clk_ops stm_pll3200c32_a9_ops; static const struct clk_ops st_pll1200c32_ops; +static const struct clk_ops stm_pll4600c28_ops; static const struct clkgen_pll_data st_pll1600c65_ax = { .pdn_status = CLKGEN_FIELD(0x0, 0x1, 19), @@ -256,6 +264,22 @@ static const struct clkgen_pll_data st_pll3200c32_407_a9 = { .ops = &stm_pll3200c32_a9_ops, }; +static struct clkgen_pll_data st_pll4600c28_418_a9 = { + /* 418 A9 */ + .pdn_status = CLKGEN_FIELD(0x1a8, 0x1, 0), + .pdn_ctrl = CLKGEN_FIELD(0x1a8, 0x1, 0), + .locked_status = CLKGEN_FIELD(0x87c, 0x1, 0), + .ndiv = CLKGEN_FIELD(0x1b0, C28_NDIV_MASK, 0), + .idf = CLKGEN_FIELD(0x1a8, C28_IDF_MASK, 25), + .num_odfs = 1, + .odf = { CLKGEN_FIELD(0x1b0, C28_ODF_MASK, 8) }, + .odf_gate = { CLKGEN_FIELD(0x1ac, 0x1, 28) }, + .switch2pll_en = true, + .switch2pll = CLKGEN_FIELD(0x1a4, 0x1, 1), + .lock = &clkgen_a9_lock, + .ops = &stm_pll4600c28_ops, +}; + /** * DOC: Clock Generated by PLL, rate set and enabled by bootloader * @@ -611,6 +635,163 @@ static unsigned long recalc_stm_pll1200c32(struct clk_hw *hw, return rate; } +/* PLL output structure + * FVCO >> /2 >> FVCOBY2 (no output) + * |> Divider (ODF) >> PHI + * + * FVCOby2 output = (input * 2 * NDIV) / IDF (assuming FRAC_CONTROL==L) + * + * Rules: + * 4Mhz <= INFF input <= 350Mhz + * 4Mhz <= INFIN (INFF / IDF) <= 50Mhz + * 19.05Mhz <= FVCOby2 output (PHI w ODF=1) <= 3000Mhz + * 1 <= i (register/dec value for IDF) <= 7 + * 8 <= n (register/dec value for NDIV) <= 246 + */ + +static int clk_pll4600c28_get_params(unsigned long input, unsigned long output, + struct stm_pll *pll) +{ + + unsigned long i, infin, n; + unsigned long deviation = ~0; + unsigned long new_freq, new_deviation; + + /* Output clock range: 19Mhz to 3000Mhz */ + if (output < 19000000 || output > 3000000000u) + return -EINVAL; + + /* For better jitter, IDF should be smallest and NDIV must be maximum */ + for (i = 1; i <= 7 && deviation; i++) { + /* INFIN checks */ + infin = input / i; + if (infin < 4000000 || infin > 50000000) + continue; /* Invalid case */ + + n = output / (infin * 2); + if (n < 8 || n > 246) + continue; /* Invalid case */ + if (n < 246) + n++; /* To work around 'y' when n=x.y */ + + for (; n >= 8 && deviation; n--) { + new_freq = infin * 2 * n; + if (new_freq < output) + break; /* Optimization: shorting loop */ + + new_deviation = new_freq - output; + if (!new_deviation || new_deviation < deviation) { + pll->idf = i; + pll->ndiv = n; + deviation = new_deviation; + } + } + } + + if (deviation == ~0) /* No solution found */ + return -EINVAL; + + return 0; +} + +static int clk_pll4600c28_get_rate(unsigned long input, struct stm_pll *pll, + unsigned long *rate) +{ + if (!pll->idf) + pll->idf = 1; + + *rate = (input / pll->idf) * 2 * pll->ndiv; + + return 0; +} + +static unsigned long recalc_stm_pll4600c28(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct clkgen_pll *pll = to_clkgen_pll(hw); + struct stm_pll params; + unsigned long rate; + + if (!clkgen_pll_is_enabled(hw) || !clkgen_pll_is_locked(hw)) + return 0; + + params.ndiv = CLKGEN_READ(pll, ndiv); + params.idf = CLKGEN_READ(pll, idf); + + clk_pll4600c28_get_rate(parent_rate, ¶ms, &rate); + + pr_debug("%s:%s rate %lu\n", __clk_get_name(hw->clk), __func__, rate); + + return rate; +} + +static long round_rate_stm_pll4600c28(struct clk_hw *hw, unsigned long rate, + unsigned long *prate) +{ + struct stm_pll params; + + if (!clk_pll4600c28_get_params(*prate, rate, ¶ms)) { + clk_pll4600c28_get_rate(*prate, ¶ms, &rate); + } else { + pr_debug("%s: %s rate %ld Invalid\n", __func__, + __clk_get_name(hw->clk), rate); + return 0; + } + + pr_debug("%s: %s new rate %ld [ndiv=%u] [idf=%u]\n", + __func__, __clk_get_name(hw->clk), + rate, (unsigned int)params.ndiv, + (unsigned int)params.idf); + + return rate; +} + +static int set_rate_stm_pll4600c28(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct clkgen_pll *pll = to_clkgen_pll(hw); + struct stm_pll params; + long hwrate; + unsigned long flags = 0; + + if (!rate || !parent_rate) + return -EINVAL; + + if (!clk_pll4600c28_get_params(parent_rate, rate, ¶ms)) { + clk_pll4600c28_get_rate(parent_rate, ¶ms, &hwrate); + } else { + pr_debug("%s: %s rate %ld Invalid\n", __func__, + __clk_get_name(hw->clk), rate); + return -EINVAL; + } + + pr_debug("%s: %s new rate %ld [ndiv=0x%x] [idf=0x%x]\n", + __func__, __clk_get_name(hw->clk), + hwrate, (unsigned int)params.ndiv, + (unsigned int)params.idf); + + if (!hwrate) + return -EINVAL; + + pll->ndiv = params.ndiv; + pll->idf = params.idf; + + __clkgen_pll_disable(hw); + + if (pll->lock) + spin_lock_irqsave(pll->lock, flags); + + CLKGEN_WRITE(pll, ndiv, pll->ndiv); + CLKGEN_WRITE(pll, idf, pll->idf); + + if (pll->lock) + spin_unlock_irqrestore(pll->lock, flags); + + __clkgen_pll_enable(hw); + + return 0; +} + static const struct clk_ops st_pll1600c65_ops = { .enable = clkgen_pll_enable, .disable = clkgen_pll_disable, @@ -648,6 +829,15 @@ static const struct clk_ops st_pll1200c32_ops = { .recalc_rate = recalc_stm_pll1200c32, }; +static const struct clk_ops stm_pll4600c28_ops = { + .enable = clkgen_pll_enable, + .disable = clkgen_pll_disable, + .is_enabled = clkgen_pll_is_enabled, + .recalc_rate = recalc_stm_pll4600c28, + .round_rate = round_rate_stm_pll4600c28, + .set_rate = set_rate_stm_pll4600c28, +}; + static struct clk * __init clkgen_pll_register(const char *parent_name, struct clkgen_pll_data *pll_data, void __iomem *reg, @@ -893,6 +1083,10 @@ static const struct of_device_id c32_pll_of_match[] = { .compatible = "st,stih407-plls-c32-a9", .data = &st_pll3200c32_407_a9, }, + { + .compatible = "st,stih418-plls-c28-a9", + .data = &st_pll4600c28_418_a9, + }, {} }; |