From 5c89658a2ef38bace96cf9d4474d59a32d06609d Mon Sep 17 00:00:00 2001 From: Tomasz Figa Date: Mon, 26 Aug 2013 19:09:07 +0200 Subject: clk: samsung: pll: Add support for rate configuration of PLL46xx This patch implements round_rate and set_rate callbacks of PLL46xx driver to allow reconfiguration of PLL at runtime. Signed-off-by: Tomasz Figa Signed-off-by: Kyungmin Park Reviewed-by: Sylwester Nawrocki Signed-off-by: Mike Turquette diff --git a/drivers/clk/samsung/clk-pll.c b/drivers/clk/samsung/clk-pll.c index d963b3e..529e11d 100644 --- a/drivers/clk/samsung/clk-pll.c +++ b/drivers/clk/samsung/clk-pll.c @@ -411,10 +411,13 @@ static const struct clk_ops samsung_pll45xx_clk_min_ops = { /* * PLL46xx Clock Type */ +#define PLL46XX_LOCK_FACTOR 3000 +#define PLL46XX_VSEL_MASK (1) #define PLL46XX_MDIV_MASK (0x1FF) #define PLL46XX_PDIV_MASK (0x3F) #define PLL46XX_SDIV_MASK (0x7) +#define PLL46XX_VSEL_SHIFT (27) #define PLL46XX_MDIV_SHIFT (16) #define PLL46XX_PDIV_SHIFT (8) #define PLL46XX_SDIV_SHIFT (0) @@ -422,6 +425,15 @@ static const struct clk_ops samsung_pll45xx_clk_min_ops = { #define PLL46XX_KDIV_MASK (0xFFFF) #define PLL4650C_KDIV_MASK (0xFFF) #define PLL46XX_KDIV_SHIFT (0) +#define PLL46XX_MFR_MASK (0x3F) +#define PLL46XX_MRR_MASK (0x1F) +#define PLL46XX_KDIV_SHIFT (0) +#define PLL46XX_MFR_SHIFT (16) +#define PLL46XX_MRR_SHIFT (24) + +#define PLL46XX_ENABLE BIT(31) +#define PLL46XX_LOCKED BIT(29) +#define PLL46XX_VSEL BIT(27) static unsigned long samsung_pll46xx_recalc_rate(struct clk_hw *hw, unsigned long parent_rate) @@ -446,8 +458,102 @@ static unsigned long samsung_pll46xx_recalc_rate(struct clk_hw *hw, return (unsigned long)fvco; } +static bool samsung_pll46xx_mpk_change(u32 pll_con0, u32 pll_con1, + const struct samsung_pll_rate_table *rate) +{ + u32 old_mdiv, old_pdiv, old_kdiv; + + old_mdiv = (pll_con0 >> PLL46XX_MDIV_SHIFT) & PLL46XX_MDIV_MASK; + old_pdiv = (pll_con0 >> PLL46XX_PDIV_SHIFT) & PLL46XX_PDIV_MASK; + old_kdiv = (pll_con1 >> PLL46XX_KDIV_SHIFT) & PLL46XX_KDIV_MASK; + + return (old_mdiv != rate->mdiv || old_pdiv != rate->pdiv + || old_kdiv != rate->kdiv); +} + +static int samsung_pll46xx_set_rate(struct clk_hw *hw, unsigned long drate, + unsigned long prate) +{ + struct samsung_clk_pll *pll = to_clk_pll(hw); + const struct samsung_pll_rate_table *rate; + u32 con0, con1, lock; + ktime_t start; + + /* Get required rate settings from table */ + rate = samsung_get_pll_settings(pll, drate); + if (!rate) { + pr_err("%s: Invalid rate : %lu for pll clk %s\n", __func__, + drate, __clk_get_name(hw->clk)); + return -EINVAL; + } + + con0 = __raw_readl(pll->con_reg); + con1 = __raw_readl(pll->con_reg + 0x4); + + if (!(samsung_pll46xx_mpk_change(con0, con1, rate))) { + /* If only s change, change just s value only*/ + con0 &= ~(PLL46XX_SDIV_MASK << PLL46XX_SDIV_SHIFT); + con0 |= rate->sdiv << PLL46XX_SDIV_SHIFT; + __raw_writel(con0, pll->con_reg); + + return 0; + } + + /* Set PLL lock time. */ + lock = rate->pdiv * PLL46XX_LOCK_FACTOR; + if (lock > 0xffff) + /* Maximum lock time bitfield is 16-bit. */ + lock = 0xffff; + + /* Set PLL PMS and VSEL values. */ + con0 &= ~((PLL46XX_MDIV_MASK << PLL46XX_MDIV_SHIFT) | + (PLL46XX_PDIV_MASK << PLL46XX_PDIV_SHIFT) | + (PLL46XX_SDIV_MASK << PLL46XX_SDIV_SHIFT) | + (PLL46XX_VSEL_MASK << PLL46XX_VSEL_SHIFT)); + con0 |= (rate->mdiv << PLL46XX_MDIV_SHIFT) | + (rate->pdiv << PLL46XX_PDIV_SHIFT) | + (rate->sdiv << PLL46XX_SDIV_SHIFT) | + (rate->vsel << PLL46XX_VSEL_SHIFT); + + /* Set PLL K, MFR and MRR values. */ + con1 = __raw_readl(pll->con_reg + 0x4); + con1 &= ~((PLL46XX_KDIV_MASK << PLL46XX_KDIV_SHIFT) | + (PLL46XX_MFR_MASK << PLL46XX_MFR_SHIFT) | + (PLL46XX_MRR_MASK << PLL46XX_MRR_SHIFT)); + con1 |= (rate->kdiv << PLL46XX_KDIV_SHIFT) | + (rate->mfr << PLL46XX_MFR_SHIFT) | + (rate->mrr << PLL46XX_MRR_SHIFT); + + /* Write configuration to PLL */ + __raw_writel(lock, pll->lock_reg); + __raw_writel(con0, pll->con_reg); + __raw_writel(con1, pll->con_reg + 0x4); + + /* Wait for locking. */ + start = ktime_get(); + while (!(__raw_readl(pll->con_reg) & PLL46XX_LOCKED)) { + ktime_t delta = ktime_sub(ktime_get(), start); + + if (ktime_to_ms(delta) > PLL_TIMEOUT_MS) { + pr_err("%s: could not lock PLL %s\n", + __func__, __clk_get_name(hw->clk)); + return -EFAULT; + } + + cpu_relax(); + } + + return 0; +} + static const struct clk_ops samsung_pll46xx_clk_ops = { .recalc_rate = samsung_pll46xx_recalc_rate, + .round_rate = samsung_pll_round_rate, + .set_rate = samsung_pll46xx_set_rate, +}; + +static const struct clk_ops samsung_pll46xx_clk_min_ops = { + .recalc_rate = samsung_pll46xx_recalc_rate, }; /* @@ -675,7 +781,10 @@ static void __init _samsung_clk_register_pll(struct samsung_pll_clock *pll_clk, case pll_4600: case pll_4650: case pll_4650c: - init.ops = &samsung_pll46xx_clk_ops; + if (!pll->rate_table) + init.ops = &samsung_pll46xx_clk_min_ops; + else + init.ops = &samsung_pll46xx_clk_ops; break; default: pr_warn("%s: Unknown pll type for pll clk %s\n", diff --git a/drivers/clk/samsung/clk-pll.h b/drivers/clk/samsung/clk-pll.h index f3c85bf..6c39030 100644 --- a/drivers/clk/samsung/clk-pll.h +++ b/drivers/clk/samsung/clk-pll.h @@ -53,6 +53,28 @@ enum samsung_pll_type { .afc = (_afc), \ } +#define PLL_4600_RATE(_rate, _m, _p, _s, _k, _vsel) \ + { \ + .rate = (_rate), \ + .mdiv = (_m), \ + .pdiv = (_p), \ + .sdiv = (_s), \ + .kdiv = (_k), \ + .vsel = (_vsel), \ + } + +#define PLL_4650_RATE(_rate, _m, _p, _s, _k, _mfr, _mrr, _vsel) \ + { \ + .rate = (_rate), \ + .mdiv = (_m), \ + .pdiv = (_p), \ + .sdiv = (_s), \ + .kdiv = (_k), \ + .mfr = (_mfr), \ + .mrr = (_mrr), \ + .vsel = (_vsel), \ + } + /* NOTE: Rate table should be kept sorted in descending order. */ struct samsung_pll_rate_table { @@ -62,6 +84,9 @@ struct samsung_pll_rate_table { unsigned int sdiv; unsigned int kdiv; unsigned int afc; + unsigned int mfr; + unsigned int mrr; + unsigned int vsel; }; extern struct clk * __init samsung_clk_register_pll2550x(const char *name, -- cgit v0.10.2