diff options
Diffstat (limited to 'drivers/clk/meson/clk-mpll.c')
-rw-r--r-- | drivers/clk/meson/clk-mpll.c | 154 |
1 files changed, 150 insertions, 4 deletions
diff --git a/drivers/clk/meson/clk-mpll.c b/drivers/clk/meson/clk-mpll.c index 03af79005ddb..39eab69fe51a 100644 --- a/drivers/clk/meson/clk-mpll.c +++ b/drivers/clk/meson/clk-mpll.c @@ -64,17 +64,51 @@ #include <linux/clk-provider.h> #include "clkc.h" -#define SDM_MAX 16384 +#define SDM_DEN 16384 +#define N2_MIN 4 +#define N2_MAX 511 #define to_meson_clk_mpll(_hw) container_of(_hw, struct meson_clk_mpll, hw) +static long rate_from_params(unsigned long parent_rate, + unsigned long sdm, + unsigned long n2) +{ + unsigned long divisor = (SDM_DEN * n2) + sdm; + + if (n2 < N2_MIN) + return -EINVAL; + + return DIV_ROUND_UP_ULL((u64)parent_rate * SDM_DEN, divisor); +} + +static void params_from_rate(unsigned long requested_rate, + unsigned long parent_rate, + unsigned long *sdm, + unsigned long *n2) +{ + uint64_t div = parent_rate; + unsigned long rem = do_div(div, requested_rate); + + if (div < N2_MIN) { + *n2 = N2_MIN; + *sdm = 0; + } else if (div > N2_MAX) { + *n2 = N2_MAX; + *sdm = SDM_DEN - 1; + } else { + *n2 = div; + *sdm = DIV_ROUND_UP(rem * SDM_DEN, requested_rate); + } +} + static unsigned long mpll_recalc_rate(struct clk_hw *hw, unsigned long parent_rate) { struct meson_clk_mpll *mpll = to_meson_clk_mpll(hw); struct parm *p; - unsigned long rate = 0; unsigned long reg, sdm, n2; + long rate; p = &mpll->sdm; reg = readl(mpll->base + p->reg_off); @@ -84,11 +118,123 @@ static unsigned long mpll_recalc_rate(struct clk_hw *hw, reg = readl(mpll->base + p->reg_off); n2 = PARM_GET(p->width, p->shift, reg); - rate = (parent_rate * SDM_MAX) / ((SDM_MAX * n2) + sdm); + rate = rate_from_params(parent_rate, sdm, n2); + if (rate < 0) + return 0; return rate; } +static long mpll_round_rate(struct clk_hw *hw, + unsigned long rate, + unsigned long *parent_rate) +{ + unsigned long sdm, n2; + + params_from_rate(rate, *parent_rate, &sdm, &n2); + return rate_from_params(*parent_rate, sdm, n2); +} + +static int mpll_set_rate(struct clk_hw *hw, + unsigned long rate, + unsigned long parent_rate) +{ + struct meson_clk_mpll *mpll = to_meson_clk_mpll(hw); + struct parm *p; + unsigned long reg, sdm, n2; + unsigned long flags = 0; + + params_from_rate(rate, parent_rate, &sdm, &n2); + + if (mpll->lock) + spin_lock_irqsave(mpll->lock, flags); + else + __acquire(mpll->lock); + + p = &mpll->sdm; + reg = readl(mpll->base + p->reg_off); + reg = PARM_SET(p->width, p->shift, reg, sdm); + writel(reg, mpll->base + p->reg_off); + + p = &mpll->sdm_en; + reg = readl(mpll->base + p->reg_off); + reg = PARM_SET(p->width, p->shift, reg, 1); + writel(reg, mpll->base + p->reg_off); + + p = &mpll->n2; + reg = readl(mpll->base + p->reg_off); + reg = PARM_SET(p->width, p->shift, reg, n2); + writel(reg, mpll->base + p->reg_off); + + if (mpll->lock) + spin_unlock_irqrestore(mpll->lock, flags); + else + __release(mpll->lock); + + return 0; +} + +static void mpll_enable_core(struct clk_hw *hw, int enable) +{ + struct meson_clk_mpll *mpll = to_meson_clk_mpll(hw); + struct parm *p; + unsigned long reg; + unsigned long flags = 0; + + if (mpll->lock) + spin_lock_irqsave(mpll->lock, flags); + else + __acquire(mpll->lock); + + p = &mpll->en; + reg = readl(mpll->base + p->reg_off); + reg = PARM_SET(p->width, p->shift, reg, enable ? 1 : 0); + writel(reg, mpll->base + p->reg_off); + + if (mpll->lock) + spin_unlock_irqrestore(mpll->lock, flags); + else + __release(mpll->lock); +} + + +static int mpll_enable(struct clk_hw *hw) +{ + mpll_enable_core(hw, 1); + + return 0; +} + +static void mpll_disable(struct clk_hw *hw) +{ + mpll_enable_core(hw, 0); +} + +static int mpll_is_enabled(struct clk_hw *hw) +{ + struct meson_clk_mpll *mpll = to_meson_clk_mpll(hw); + struct parm *p; + unsigned long reg; + int en; + + p = &mpll->en; + reg = readl(mpll->base + p->reg_off); + en = PARM_GET(p->width, p->shift, reg); + + return en; +} + const struct clk_ops meson_clk_mpll_ro_ops = { - .recalc_rate = mpll_recalc_rate, + .recalc_rate = mpll_recalc_rate, + .round_rate = mpll_round_rate, + .is_enabled = mpll_is_enabled, +}; + +const struct clk_ops meson_clk_mpll_ops = { + .recalc_rate = mpll_recalc_rate, + .round_rate = mpll_round_rate, + .set_rate = mpll_set_rate, + .enable = mpll_enable, + .disable = mpll_disable, + .is_enabled = mpll_is_enabled, }; |