diff options
Diffstat (limited to 'kernel/drivers/clk/pistachio/clk-pll.c')
| -rw-r--r-- | kernel/drivers/clk/pistachio/clk-pll.c | 169 |
1 files changed, 141 insertions, 28 deletions
diff --git a/kernel/drivers/clk/pistachio/clk-pll.c b/kernel/drivers/clk/pistachio/clk-pll.c index ebd0d2a3b..7e8daab90 100644 --- a/kernel/drivers/clk/pistachio/clk-pll.c +++ b/kernel/drivers/clk/pistachio/clk-pll.c @@ -6,9 +6,12 @@ * version 2, as published by the Free Software Foundation. */ +#define pr_fmt(fmt) "%s: " fmt, __func__ + #include <linux/clk-provider.h> #include <linux/io.h> #include <linux/kernel.h> +#include <linux/printk.h> #include <linux/slab.h> #include "clk.h" @@ -50,6 +53,24 @@ #define PLL_CTRL4 0x10 #define PLL_FRAC_CTRL4_BYPASS BIT(28) +#define MIN_PFD 9600000UL +#define MIN_VCO_LA 400000000UL +#define MAX_VCO_LA 1600000000UL +#define MIN_VCO_FRAC_INT 600000000UL +#define MAX_VCO_FRAC_INT 1600000000UL +#define MIN_VCO_FRAC_FRAC 600000000UL +#define MAX_VCO_FRAC_FRAC 2400000000UL +#define MIN_OUTPUT_LA 8000000UL +#define MAX_OUTPUT_LA 1600000000UL +#define MIN_OUTPUT_FRAC 12000000UL +#define MAX_OUTPUT_FRAC 1600000000UL + +/* Fractional PLL operating modes */ +enum pll_mode { + PLL_MODE_FRAC, + PLL_MODE_INT, +}; + struct pistachio_clk_pll { struct clk_hw hw; void __iomem *base; @@ -67,12 +88,16 @@ static inline void pll_writel(struct pistachio_clk_pll *pll, u32 val, u32 reg) writel(val, pll->base + reg); } -static inline u32 do_div_round_closest(u64 dividend, u32 divisor) +static inline void pll_lock(struct pistachio_clk_pll *pll) { - dividend += divisor / 2; - do_div(dividend, divisor); + while (!(pll_readl(pll, PLL_STATUS) & PLL_STATUS_LOCK)) + cpu_relax(); +} - return dividend; +static inline u64 do_div_round_closest(u64 dividend, u64 divisor) +{ + dividend += divisor / 2; + return div64_u64(dividend, divisor); } static inline struct pistachio_clk_pll *to_pistachio_pll(struct clk_hw *hw) @@ -80,6 +105,29 @@ static inline struct pistachio_clk_pll *to_pistachio_pll(struct clk_hw *hw) return container_of(hw, struct pistachio_clk_pll, hw); } +static inline enum pll_mode pll_frac_get_mode(struct clk_hw *hw) +{ + struct pistachio_clk_pll *pll = to_pistachio_pll(hw); + u32 val; + + val = pll_readl(pll, PLL_CTRL3) & PLL_FRAC_CTRL3_DSMPD; + return val ? PLL_MODE_INT : PLL_MODE_FRAC; +} + +static inline void pll_frac_set_mode(struct clk_hw *hw, enum pll_mode mode) +{ + struct pistachio_clk_pll *pll = to_pistachio_pll(hw); + u32 val; + + val = pll_readl(pll, PLL_CTRL3); + if (mode == PLL_MODE_INT) + val |= PLL_FRAC_CTRL3_DSMPD | PLL_FRAC_CTRL3_DACPD; + else + val &= ~(PLL_FRAC_CTRL3_DSMPD | PLL_FRAC_CTRL3_DACPD); + + pll_writel(pll, val, PLL_CTRL3); +} + static struct pistachio_pll_rate_table * pll_get_params(struct pistachio_clk_pll *pll, unsigned long fref, unsigned long fout) @@ -123,6 +171,8 @@ static int pll_gf40lp_frac_enable(struct clk_hw *hw) val &= ~PLL_FRAC_CTRL4_BYPASS; pll_writel(pll, val, PLL_CTRL4); + pll_lock(pll); + return 0; } @@ -148,16 +198,33 @@ static int pll_gf40lp_frac_set_rate(struct clk_hw *hw, unsigned long rate, { struct pistachio_clk_pll *pll = to_pistachio_pll(hw); struct pistachio_pll_rate_table *params; - bool was_enabled; - u32 val; + int enabled = pll_gf40lp_frac_is_enabled(hw); + u64 val, vco, old_postdiv1, old_postdiv2; + const char *name = clk_hw_get_name(hw); + + if (rate < MIN_OUTPUT_FRAC || rate > MAX_OUTPUT_FRAC) + return -EINVAL; params = pll_get_params(pll, parent_rate, rate); - if (!params) + if (!params || !params->refdiv) return -EINVAL; - was_enabled = pll_gf40lp_frac_is_enabled(hw); - if (!was_enabled) - pll_gf40lp_frac_enable(hw); + /* calculate vco */ + vco = params->fref; + vco *= (params->fbdiv << 24) + params->frac; + vco = div64_u64(vco, params->refdiv << 24); + + if (vco < MIN_VCO_FRAC_FRAC || vco > MAX_VCO_FRAC_FRAC) + pr_warn("%s: VCO %llu is out of range %lu..%lu\n", name, vco, + MIN_VCO_FRAC_FRAC, MAX_VCO_FRAC_FRAC); + + val = div64_u64(params->fref, params->refdiv); + if (val < MIN_PFD) + pr_warn("%s: PFD %llu is too low (min %lu)\n", + name, val, MIN_PFD); + if (val > vco / 16) + pr_warn("%s: PFD %llu is too high (max %llu)\n", + name, val, vco / 16); val = pll_readl(pll, PLL_CTRL1); val &= ~((PLL_CTRL1_REFDIV_MASK << PLL_CTRL1_REFDIV_SHIFT) | @@ -167,6 +234,19 @@ static int pll_gf40lp_frac_set_rate(struct clk_hw *hw, unsigned long rate, pll_writel(pll, val, PLL_CTRL1); val = pll_readl(pll, PLL_CTRL2); + + old_postdiv1 = (val >> PLL_FRAC_CTRL2_POSTDIV1_SHIFT) & + PLL_FRAC_CTRL2_POSTDIV1_MASK; + old_postdiv2 = (val >> PLL_FRAC_CTRL2_POSTDIV2_SHIFT) & + PLL_FRAC_CTRL2_POSTDIV2_MASK; + if (enabled && + (params->postdiv1 != old_postdiv1 || + params->postdiv2 != old_postdiv2)) + pr_warn("%s: changing postdiv while PLL is enabled\n", name); + + if (params->postdiv2 > params->postdiv1) + pr_warn("%s: postdiv2 should not exceed postdiv1\n", name); + val &= ~((PLL_FRAC_CTRL2_FRAC_MASK << PLL_FRAC_CTRL2_FRAC_SHIFT) | (PLL_FRAC_CTRL2_POSTDIV1_MASK << PLL_FRAC_CTRL2_POSTDIV1_SHIFT) | @@ -177,11 +257,14 @@ static int pll_gf40lp_frac_set_rate(struct clk_hw *hw, unsigned long rate, (params->postdiv2 << PLL_FRAC_CTRL2_POSTDIV2_SHIFT); pll_writel(pll, val, PLL_CTRL2); - while (!(pll_readl(pll, PLL_STATUS) & PLL_STATUS_LOCK)) - cpu_relax(); + /* set operating mode */ + if (params->frac) + pll_frac_set_mode(hw, PLL_MODE_FRAC); + else + pll_frac_set_mode(hw, PLL_MODE_INT); - if (!was_enabled) - pll_gf40lp_frac_disable(hw); + if (enabled) + pll_lock(pll); return 0; } @@ -190,8 +273,7 @@ static unsigned long pll_gf40lp_frac_recalc_rate(struct clk_hw *hw, unsigned long parent_rate) { struct pistachio_clk_pll *pll = to_pistachio_pll(hw); - u32 val, prediv, fbdiv, frac, postdiv1, postdiv2; - u64 rate = parent_rate; + u64 val, prediv, fbdiv, frac, postdiv1, postdiv2, rate; val = pll_readl(pll, PLL_CTRL1); prediv = (val >> PLL_CTRL1_REFDIV_SHIFT) & PLL_CTRL1_REFDIV_MASK; @@ -204,7 +286,13 @@ static unsigned long pll_gf40lp_frac_recalc_rate(struct clk_hw *hw, PLL_FRAC_CTRL2_POSTDIV2_MASK; frac = (val >> PLL_FRAC_CTRL2_FRAC_SHIFT) & PLL_FRAC_CTRL2_FRAC_MASK; - rate *= (fbdiv << 24) + frac; + /* get operating mode (int/frac) and calculate rate accordingly */ + rate = parent_rate; + if (pll_frac_get_mode(hw) == PLL_MODE_FRAC) + rate *= (fbdiv << 24) + frac; + else + rate *= (fbdiv << 24); + rate = do_div_round_closest(rate, (prediv * postdiv1 * postdiv2) << 24); return rate; @@ -240,6 +328,8 @@ static int pll_gf40lp_laint_enable(struct clk_hw *hw) val &= ~PLL_INT_CTRL2_BYPASS; pll_writel(pll, val, PLL_CTRL2); + pll_lock(pll); + return 0; } @@ -265,18 +355,44 @@ static int pll_gf40lp_laint_set_rate(struct clk_hw *hw, unsigned long rate, { struct pistachio_clk_pll *pll = to_pistachio_pll(hw); struct pistachio_pll_rate_table *params; - bool was_enabled; - u32 val; + int enabled = pll_gf40lp_laint_is_enabled(hw); + u32 val, vco, old_postdiv1, old_postdiv2; + const char *name = clk_hw_get_name(hw); + + if (rate < MIN_OUTPUT_LA || rate > MAX_OUTPUT_LA) + return -EINVAL; params = pll_get_params(pll, parent_rate, rate); - if (!params) + if (!params || !params->refdiv) return -EINVAL; - was_enabled = pll_gf40lp_laint_is_enabled(hw); - if (!was_enabled) - pll_gf40lp_laint_enable(hw); + vco = div_u64(params->fref * params->fbdiv, params->refdiv); + if (vco < MIN_VCO_LA || vco > MAX_VCO_LA) + pr_warn("%s: VCO %u is out of range %lu..%lu\n", name, vco, + MIN_VCO_LA, MAX_VCO_LA); + + val = div_u64(params->fref, params->refdiv); + if (val < MIN_PFD) + pr_warn("%s: PFD %u is too low (min %lu)\n", + name, val, MIN_PFD); + if (val > vco / 16) + pr_warn("%s: PFD %u is too high (max %u)\n", + name, val, vco / 16); val = pll_readl(pll, PLL_CTRL1); + + old_postdiv1 = (val >> PLL_INT_CTRL1_POSTDIV1_SHIFT) & + PLL_INT_CTRL1_POSTDIV1_MASK; + old_postdiv2 = (val >> PLL_INT_CTRL1_POSTDIV2_SHIFT) & + PLL_INT_CTRL1_POSTDIV2_MASK; + if (enabled && + (params->postdiv1 != old_postdiv1 || + params->postdiv2 != old_postdiv2)) + pr_warn("%s: changing postdiv while PLL is enabled\n", name); + + if (params->postdiv2 > params->postdiv1) + pr_warn("%s: postdiv2 should not exceed postdiv1\n", name); + val &= ~((PLL_CTRL1_REFDIV_MASK << PLL_CTRL1_REFDIV_SHIFT) | (PLL_CTRL1_FBDIV_MASK << PLL_CTRL1_FBDIV_SHIFT) | (PLL_INT_CTRL1_POSTDIV1_MASK << PLL_INT_CTRL1_POSTDIV1_SHIFT) | @@ -287,11 +403,8 @@ static int pll_gf40lp_laint_set_rate(struct clk_hw *hw, unsigned long rate, (params->postdiv2 << PLL_INT_CTRL1_POSTDIV2_SHIFT); pll_writel(pll, val, PLL_CTRL1); - while (!(pll_readl(pll, PLL_STATUS) & PLL_STATUS_LOCK)) - cpu_relax(); - - if (!was_enabled) - pll_gf40lp_laint_disable(hw); + if (enabled) + pll_lock(pll); return 0; } |