diff options
Diffstat (limited to 'drivers/clk/samsung/clk-pll.c')
| -rw-r--r-- | drivers/clk/samsung/clk-pll.c | 105 |
1 files changed, 104 insertions, 1 deletions
diff --git a/drivers/clk/samsung/clk-pll.c b/drivers/clk/samsung/clk-pll.c index 83942318df13..03486e339b64 100644 --- a/drivers/clk/samsung/clk-pll.c +++ b/drivers/clk/samsung/clk-pll.c @@ -24,16 +24,51 @@ struct samsung_clk_pll { #define to_clk_pll(_hw) container_of(_hw, struct samsung_clk_pll, hw) +static const struct samsung_pll_rate_table *samsung_get_pll_settings( + struct samsung_clk_pll *pll, unsigned long rate) +{ + const struct samsung_pll_rate_table *rate_table = pll->rate_table; + int i; + + for (i = 0; i < pll->rate_count; i++) { + if (rate == rate_table[i].rate) + return &rate_table[i]; + } + + return NULL; +} + +static long samsung_pll_round_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_table = pll->rate_table; + int i; + + /* Assumming rate_table is in descending order */ + for (i = 0; i < pll->rate_count; i++) { + if (drate >= rate_table[i].rate) + return rate_table[i].rate; + } + + /* return minimum supported value */ + return rate_table[i - 1].rate; +} + /* * PLL35xx Clock Type */ +/* Maximum lock time can be 270 * PDIV cycles */ +#define PLL35XX_LOCK_FACTOR (270) #define PLL35XX_MDIV_MASK (0x3FF) #define PLL35XX_PDIV_MASK (0x3F) #define PLL35XX_SDIV_MASK (0x7) +#define PLL35XX_LOCK_STAT_MASK (0x1) #define PLL35XX_MDIV_SHIFT (16) #define PLL35XX_PDIV_SHIFT (8) #define PLL35XX_SDIV_SHIFT (0) +#define PLL35XX_LOCK_STAT_SHIFT (29) static unsigned long samsung_pll35xx_recalc_rate(struct clk_hw *hw, unsigned long parent_rate) @@ -53,8 +88,73 @@ static unsigned long samsung_pll35xx_recalc_rate(struct clk_hw *hw, return (unsigned long)fvco; } +static inline bool samsung_pll35xx_mp_change( + const struct samsung_pll_rate_table *rate, u32 pll_con) +{ + u32 old_mdiv, old_pdiv; + + old_mdiv = (pll_con >> PLL35XX_MDIV_SHIFT) & PLL35XX_MDIV_MASK; + old_pdiv = (pll_con >> PLL35XX_PDIV_SHIFT) & PLL35XX_PDIV_MASK; + + return (rate->mdiv != old_mdiv || rate->pdiv != old_pdiv); +} + +static int samsung_pll35xx_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 tmp; + + /* 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; + } + + tmp = __raw_readl(pll->con_reg); + + if (!(samsung_pll35xx_mp_change(rate, tmp))) { + /* If only s change, change just s value only*/ + tmp &= ~(PLL35XX_SDIV_MASK << PLL35XX_SDIV_SHIFT); + tmp |= rate->sdiv << PLL35XX_SDIV_SHIFT; + __raw_writel(tmp, pll->con_reg); + + return 0; + } + + /* Set PLL lock time. */ + __raw_writel(rate->pdiv * PLL35XX_LOCK_FACTOR, + pll->lock_reg); + + /* Change PLL PMS values */ + tmp &= ~((PLL35XX_MDIV_MASK << PLL35XX_MDIV_SHIFT) | + (PLL35XX_PDIV_MASK << PLL35XX_PDIV_SHIFT) | + (PLL35XX_SDIV_MASK << PLL35XX_SDIV_SHIFT)); + tmp |= (rate->mdiv << PLL35XX_MDIV_SHIFT) | + (rate->pdiv << PLL35XX_PDIV_SHIFT) | + (rate->sdiv << PLL35XX_SDIV_SHIFT); + __raw_writel(tmp, pll->con_reg); + + /* wait_lock_time */ + do { + cpu_relax(); + tmp = __raw_readl(pll->con_reg); + } while (!(tmp & (PLL35XX_LOCK_STAT_MASK + << PLL35XX_LOCK_STAT_SHIFT))); + return 0; +} + static const struct clk_ops samsung_pll35xx_clk_ops = { .recalc_rate = samsung_pll35xx_recalc_rate, + .round_rate = samsung_pll_round_rate, + .set_rate = samsung_pll35xx_set_rate, +}; + +static const struct clk_ops samsung_pll35xx_clk_min_ops = { + .recalc_rate = samsung_pll35xx_recalc_rate, }; /* @@ -385,7 +485,10 @@ static void __init _samsung_clk_register_pll(struct samsung_pll_clock *pll_clk, /* clk_ops for 35xx and 2550 are similar */ case pll_35xx: case pll_2550: - init.ops = &samsung_pll35xx_clk_ops; + if (!pll->rate_table) + init.ops = &samsung_pll35xx_clk_min_ops; + else + init.ops = &samsung_pll35xx_clk_ops; break; /* clk_ops for 36xx and 2650 are similar */ case pll_36xx: |