diff options
Diffstat (limited to 'drivers/clk/ti/fapll.c')
| -rw-r--r-- | drivers/clk/ti/fapll.c | 270 |
1 files changed, 262 insertions, 8 deletions
diff --git a/drivers/clk/ti/fapll.c b/drivers/clk/ti/fapll.c index d21640634adf..ffcd8e09e85b 100644 --- a/drivers/clk/ti/fapll.c +++ b/drivers/clk/ti/fapll.c @@ -11,19 +11,27 @@ #include <linux/clk-provider.h> #include <linux/delay.h> -#include <linux/slab.h> #include <linux/err.h> +#include <linux/math64.h> #include <linux/of.h> #include <linux/of_address.h> #include <linux/clk/ti.h> -#include <asm/div64.h> /* FAPLL Control Register PLL_CTRL */ +#define FAPLL_MAIN_MULT_N_SHIFT 16 +#define FAPLL_MAIN_DIV_P_SHIFT 8 #define FAPLL_MAIN_LOCK BIT(7) #define FAPLL_MAIN_PLLEN BIT(3) #define FAPLL_MAIN_BP BIT(2) #define FAPLL_MAIN_LOC_CTL BIT(0) +#define FAPLL_MAIN_MAX_MULT_N 0xffff +#define FAPLL_MAIN_MAX_DIV_P 0xff +#define FAPLL_MAIN_CLEAR_MASK \ + ((FAPLL_MAIN_MAX_MULT_N << FAPLL_MAIN_MULT_N_SHIFT) | \ + (FAPLL_MAIN_DIV_P_SHIFT << FAPLL_MAIN_DIV_P_SHIFT) | \ + FAPLL_MAIN_LOC_CTL) + /* FAPLL powerdown register PWD */ #define FAPLL_PWD_OFFSET 4 @@ -49,6 +57,10 @@ /* Synthesizer frequency register */ #define SYNTH_LDFREQ BIT(31) +#define SYNTH_PHASE_K 8 +#define SYNTH_MAX_INT_DIV 0xf +#define SYNTH_MAX_DIV_M 0xff + struct fapll_data { struct clk_hw hw; void __iomem *base; @@ -79,6 +91,48 @@ static bool ti_fapll_clock_is_bypass(struct fapll_data *fd) return !!(v & FAPLL_MAIN_BP); } +static void ti_fapll_set_bypass(struct fapll_data *fd) +{ + u32 v = readl_relaxed(fd->base); + + if (fd->bypass_bit_inverted) + v &= ~FAPLL_MAIN_BP; + else + v |= FAPLL_MAIN_BP; + writel_relaxed(v, fd->base); +} + +static void ti_fapll_clear_bypass(struct fapll_data *fd) +{ + u32 v = readl_relaxed(fd->base); + + if (fd->bypass_bit_inverted) + v |= FAPLL_MAIN_BP; + else + v &= ~FAPLL_MAIN_BP; + writel_relaxed(v, fd->base); +} + +static int ti_fapll_wait_lock(struct fapll_data *fd) +{ + int retries = FAPLL_MAX_RETRIES; + u32 v; + + while ((v = readl_relaxed(fd->base))) { + if (v & FAPLL_MAIN_LOCK) + return 0; + + if (retries-- <= 0) + break; + + udelay(1); + } + + pr_err("%s failed to lock\n", fd->name); + + return -ETIMEDOUT; +} + static int ti_fapll_enable(struct clk_hw *hw) { struct fapll_data *fd = to_fapll(hw); @@ -86,6 +140,7 @@ static int ti_fapll_enable(struct clk_hw *hw) v |= FAPLL_MAIN_PLLEN; writel_relaxed(v, fd->base); + ti_fapll_wait_lock(fd); return 0; } @@ -141,12 +196,85 @@ static u8 ti_fapll_get_parent(struct clk_hw *hw) return 0; } +static int ti_fapll_set_div_mult(unsigned long rate, + unsigned long parent_rate, + u32 *pre_div_p, u32 *mult_n) +{ + /* + * So far no luck getting decent clock with PLL divider, + * PLL does not seem to lock and the signal does not look + * right. It seems the divider can only be used together + * with the multiplier? + */ + if (rate < parent_rate) { + pr_warn("FAPLL main divider rates unsupported\n"); + return -EINVAL; + } + + *mult_n = rate / parent_rate; + if (*mult_n > FAPLL_MAIN_MAX_MULT_N) + return -EINVAL; + *pre_div_p = 1; + + return 0; +} + +static long ti_fapll_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *parent_rate) +{ + u32 pre_div_p, mult_n; + int error; + + if (!rate) + return -EINVAL; + + error = ti_fapll_set_div_mult(rate, *parent_rate, + &pre_div_p, &mult_n); + if (error) + return error; + + rate = *parent_rate / pre_div_p; + rate *= mult_n; + + return rate; +} + +static int ti_fapll_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct fapll_data *fd = to_fapll(hw); + u32 pre_div_p, mult_n, v; + int error; + + if (!rate) + return -EINVAL; + + error = ti_fapll_set_div_mult(rate, parent_rate, + &pre_div_p, &mult_n); + if (error) + return error; + + ti_fapll_set_bypass(fd); + v = readl_relaxed(fd->base); + v &= ~FAPLL_MAIN_CLEAR_MASK; + v |= pre_div_p << FAPLL_MAIN_DIV_P_SHIFT; + v |= mult_n << FAPLL_MAIN_MULT_N_SHIFT; + writel_relaxed(v, fd->base); + if (ti_fapll_is_enabled(hw)) + ti_fapll_wait_lock(fd); + ti_fapll_clear_bypass(fd); + + return 0; +} + static struct clk_ops ti_fapll_ops = { .enable = ti_fapll_enable, .disable = ti_fapll_disable, .is_enabled = ti_fapll_is_enabled, .recalc_rate = ti_fapll_recalc_rate, .get_parent = ti_fapll_get_parent, + .round_rate = ti_fapll_round_rate, + .set_rate = ti_fapll_set_rate, }; static int ti_fapll_synth_enable(struct clk_hw *hw) @@ -204,7 +332,7 @@ static unsigned long ti_fapll_synth_recalc_rate(struct clk_hw *hw, /* * Synth frequency integer and fractional divider. * Note that the phase output K is 8, so the result needs - * to be multiplied by 8. + * to be multiplied by SYNTH_PHASE_K. */ if (synth->freq) { u32 v, synth_int_div, synth_frac_div, synth_div_freq; @@ -215,14 +343,138 @@ static unsigned long ti_fapll_synth_recalc_rate(struct clk_hw *hw, synth_div_freq = (synth_int_div * 10000000) + synth_frac_div; rate *= 10000000; do_div(rate, synth_div_freq); - rate *= 8; + rate *= SYNTH_PHASE_K; } - /* Synth ost-divider M */ - synth_div_m = readl_relaxed(synth->div) & 0xff; - do_div(rate, synth_div_m); + /* Synth post-divider M */ + synth_div_m = readl_relaxed(synth->div) & SYNTH_MAX_DIV_M; - return rate; + return DIV_ROUND_UP_ULL(rate, synth_div_m); +} + +static unsigned long ti_fapll_synth_get_frac_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct fapll_synth *synth = to_synth(hw); + unsigned long current_rate, frac_rate; + u32 post_div_m; + + current_rate = ti_fapll_synth_recalc_rate(hw, parent_rate); + post_div_m = readl_relaxed(synth->div) & SYNTH_MAX_DIV_M; + frac_rate = current_rate * post_div_m; + + return frac_rate; +} + +static u32 ti_fapll_synth_set_frac_rate(struct fapll_synth *synth, + unsigned long rate, + unsigned long parent_rate) +{ + u32 post_div_m, synth_int_div = 0, synth_frac_div = 0, v; + + post_div_m = DIV_ROUND_UP_ULL((u64)parent_rate * SYNTH_PHASE_K, rate); + post_div_m = post_div_m / SYNTH_MAX_INT_DIV; + if (post_div_m > SYNTH_MAX_DIV_M) + return -EINVAL; + if (!post_div_m) + post_div_m = 1; + + for (; post_div_m < SYNTH_MAX_DIV_M; post_div_m++) { + synth_int_div = DIV_ROUND_UP_ULL((u64)parent_rate * + SYNTH_PHASE_K * + 10000000, + rate * post_div_m); + synth_frac_div = synth_int_div % 10000000; + synth_int_div /= 10000000; + + if (synth_int_div <= SYNTH_MAX_INT_DIV) + break; + } + + if (synth_int_div > SYNTH_MAX_INT_DIV) + return -EINVAL; + + v = readl_relaxed(synth->freq); + v &= ~0x1fffffff; + v |= (synth_int_div & SYNTH_MAX_INT_DIV) << 24; + v |= (synth_frac_div & 0xffffff); + v |= SYNTH_LDFREQ; + writel_relaxed(v, synth->freq); + + return post_div_m; +} + +static long ti_fapll_synth_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *parent_rate) +{ + struct fapll_synth *synth = to_synth(hw); + struct fapll_data *fd = synth->fd; + unsigned long r; + + if (ti_fapll_clock_is_bypass(fd) || !synth->div || !rate) + return -EINVAL; + + /* Only post divider m available with no fractional divider? */ + if (!synth->freq) { + unsigned long frac_rate; + u32 synth_post_div_m; + + frac_rate = ti_fapll_synth_get_frac_rate(hw, *parent_rate); + synth_post_div_m = DIV_ROUND_UP(frac_rate, rate); + r = DIV_ROUND_UP(frac_rate, synth_post_div_m); + goto out; + } + + r = *parent_rate * SYNTH_PHASE_K; + if (rate > r) + goto out; + + r = DIV_ROUND_UP_ULL(r, SYNTH_MAX_INT_DIV * SYNTH_MAX_DIV_M); + if (rate < r) + goto out; + + r = rate; +out: + return r; +} + +static int ti_fapll_synth_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct fapll_synth *synth = to_synth(hw); + struct fapll_data *fd = synth->fd; + unsigned long frac_rate, post_rate = 0; + u32 post_div_m = 0, v; + + if (ti_fapll_clock_is_bypass(fd) || !synth->div || !rate) + return -EINVAL; + + /* Produce the rate with just post divider M? */ + frac_rate = ti_fapll_synth_get_frac_rate(hw, parent_rate); + if (frac_rate < rate) { + if (!synth->freq) + return -EINVAL; + } else { + post_div_m = DIV_ROUND_UP(frac_rate, rate); + if (post_div_m && (post_div_m <= SYNTH_MAX_DIV_M)) + post_rate = DIV_ROUND_UP(frac_rate, post_div_m); + if (!synth->freq && !post_rate) + return -EINVAL; + } + + /* Need to recalculate the fractional divider? */ + if ((post_rate != rate) && synth->freq) + post_div_m = ti_fapll_synth_set_frac_rate(synth, + rate, + parent_rate); + + v = readl_relaxed(synth->div); + v &= ~SYNTH_MAX_DIV_M; + v |= post_div_m; + v |= SYNTH_LDMDIV1; + writel_relaxed(v, synth->div); + + return 0; } static struct clk_ops ti_fapll_synt_ops = { @@ -230,6 +482,8 @@ static struct clk_ops ti_fapll_synt_ops = { .disable = ti_fapll_synth_disable, .is_enabled = ti_fapll_synth_is_enabled, .recalc_rate = ti_fapll_synth_recalc_rate, + .round_rate = ti_fapll_synth_round_rate, + .set_rate = ti_fapll_synth_set_rate, }; static struct clk * __init ti_fapll_synth_setup(struct fapll_data *fd, |