diff options
Diffstat (limited to 'drivers/clk/samsung/clk-pll.c')
| -rw-r--r-- | drivers/clk/samsung/clk-pll.c | 110 |
1 files changed, 109 insertions, 1 deletions
diff --git a/drivers/clk/samsung/clk-pll.c b/drivers/clk/samsung/clk-pll.c index f2e92e81173a..4acd06169ae3 100644 --- a/drivers/clk/samsung/clk-pll.c +++ b/drivers/clk/samsung/clk-pll.c @@ -10,9 +10,12 @@ */ #include <linux/errno.h> +#include <linux/hrtimer.h> #include "clk.h" #include "clk-pll.h" +#define PLL_TIMEOUT_MS 10 + struct samsung_clk_pll { struct clk_hw hw; void __iomem *lock_reg; @@ -272,13 +275,20 @@ static const struct clk_ops samsung_pll36xx_clk_min_ops = { /* * PLL45xx Clock Type */ +#define PLL4502_LOCK_FACTOR 400 +#define PLL4508_LOCK_FACTOR 240 #define PLL45XX_MDIV_MASK (0x3FF) #define PLL45XX_PDIV_MASK (0x3F) #define PLL45XX_SDIV_MASK (0x7) +#define PLL45XX_AFC_MASK (0x1F) #define PLL45XX_MDIV_SHIFT (16) #define PLL45XX_PDIV_SHIFT (8) #define PLL45XX_SDIV_SHIFT (0) +#define PLL45XX_AFC_SHIFT (0) + +#define PLL45XX_ENABLE BIT(31) +#define PLL45XX_LOCKED BIT(29) static unsigned long samsung_pll45xx_recalc_rate(struct clk_hw *hw, unsigned long parent_rate) @@ -301,8 +311,101 @@ static unsigned long samsung_pll45xx_recalc_rate(struct clk_hw *hw, return (unsigned long)fvco; } +static bool samsung_pll45xx_mp_change(u32 pll_con0, u32 pll_con1, + const struct samsung_pll_rate_table *rate) +{ + u32 old_mdiv, old_pdiv, old_afc; + + old_mdiv = (pll_con0 >> PLL45XX_MDIV_SHIFT) & PLL45XX_MDIV_MASK; + old_pdiv = (pll_con0 >> PLL45XX_PDIV_SHIFT) & PLL45XX_PDIV_MASK; + old_afc = (pll_con1 >> PLL45XX_AFC_SHIFT) & PLL45XX_AFC_MASK; + + return (old_mdiv != rate->mdiv || old_pdiv != rate->pdiv + || old_afc != rate->afc); +} + +static int samsung_pll45xx_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; + 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_pll45xx_mp_change(con0, con1, rate))) { + /* If only s change, change just s value only*/ + con0 &= ~(PLL45XX_SDIV_MASK << PLL45XX_SDIV_SHIFT); + con0 |= rate->sdiv << PLL45XX_SDIV_SHIFT; + __raw_writel(con0, pll->con_reg); + + return 0; + } + + /* Set PLL PMS values. */ + con0 &= ~((PLL45XX_MDIV_MASK << PLL45XX_MDIV_SHIFT) | + (PLL45XX_PDIV_MASK << PLL45XX_PDIV_SHIFT) | + (PLL45XX_SDIV_MASK << PLL45XX_SDIV_SHIFT)); + con0 |= (rate->mdiv << PLL45XX_MDIV_SHIFT) | + (rate->pdiv << PLL45XX_PDIV_SHIFT) | + (rate->sdiv << PLL45XX_SDIV_SHIFT); + + /* Set PLL AFC value. */ + con1 = __raw_readl(pll->con_reg + 0x4); + con1 &= ~(PLL45XX_AFC_MASK << PLL45XX_AFC_SHIFT); + con1 |= (rate->afc << PLL45XX_AFC_SHIFT); + + /* Set PLL lock time. */ + switch (pll->type) { + case pll_4502: + __raw_writel(rate->pdiv * PLL4502_LOCK_FACTOR, pll->lock_reg); + break; + case pll_4508: + __raw_writel(rate->pdiv * PLL4508_LOCK_FACTOR, pll->lock_reg); + break; + default: + break; + }; + + /* Set new configuration. */ + __raw_writel(con1, pll->con_reg + 0x4); + __raw_writel(con0, pll->con_reg); + + /* Wait for locking. */ + start = ktime_get(); + while (!(__raw_readl(pll->con_reg) & PLL45XX_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_pll45xx_clk_ops = { .recalc_rate = samsung_pll45xx_recalc_rate, + .round_rate = samsung_pll_round_rate, + .set_rate = samsung_pll45xx_set_rate, +}; + +static const struct clk_ops samsung_pll45xx_clk_min_ops = { + .recalc_rate = samsung_pll45xx_recalc_rate, }; /* @@ -591,9 +694,14 @@ static void __init _samsung_clk_register_pll(struct samsung_pll_clock *pll_clk, init.ops = &samsung_pll35xx_clk_ops; break; case pll_4500: + init.ops = &samsung_pll45xx_clk_min_ops; + break; case pll_4502: case pll_4508: - init.ops = &samsung_pll45xx_clk_ops; + if (!pll->rate_table) + init.ops = &samsung_pll45xx_clk_min_ops; + else + init.ops = &samsung_pll45xx_clk_ops; break; /* clk_ops for 36xx and 2650 are similar */ case pll_36xx: |
