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path: root/drivers/clk/ti/fapll.c
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Diffstat (limited to 'drivers/clk/ti/fapll.c')
-rw-r--r--drivers/clk/ti/fapll.c270
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,