#include <linux/io.h>
#include <linux/math64.h>
#include <linux/module.h>
-#include <linux/of_address.h>
-#include <linux/slab.h>
-#include <linux/string.h>
+#include <linux/rational.h>
-#include "clkc.h"
+#include "clk-regmap.h"
+#include "clk-pll.h"
static inline struct meson_clk_pll_data *
meson_clk_pll_data(struct clk_regmap *clk)
return (struct meson_clk_pll_data *)clk->data;
}
+static int __pll_round_closest_mult(struct meson_clk_pll_data *pll)
+{
+ if ((pll->flags & CLK_MESON_PLL_ROUND_CLOSEST) &&
+ !MESON_PARM_APPLICABLE(&pll->frac))
+ return 1;
+
+ return 0;
+}
+
static unsigned long __pll_params_to_rate(unsigned long parent_rate,
- const struct pll_params_table *pllt,
- u16 frac,
+ unsigned int m, unsigned int n,
+ unsigned int frac,
struct meson_clk_pll_data *pll)
{
- u64 rate = (u64)parent_rate * pllt->m;
+ u64 rate = (u64)parent_rate * m;
if (frac && MESON_PARM_APPLICABLE(&pll->frac)) {
u64 frac_rate = (u64)parent_rate * frac;
(1 << pll->frac.width));
}
- return DIV_ROUND_UP_ULL(rate, pllt->n);
+ return DIV_ROUND_UP_ULL(rate, n);
}
static unsigned long meson_clk_pll_recalc_rate(struct clk_hw *hw,
{
struct clk_regmap *clk = to_clk_regmap(hw);
struct meson_clk_pll_data *pll = meson_clk_pll_data(clk);
- struct pll_params_table pllt;
- u16 frac;
+ unsigned int m, n, frac;
- pllt.n = meson_parm_read(clk->map, &pll->n);
- pllt.m = meson_parm_read(clk->map, &pll->m);
+ n = meson_parm_read(clk->map, &pll->n);
+ m = meson_parm_read(clk->map, &pll->m);
frac = MESON_PARM_APPLICABLE(&pll->frac) ?
meson_parm_read(clk->map, &pll->frac) :
0;
- return __pll_params_to_rate(parent_rate, &pllt, frac, pll);
+ return __pll_params_to_rate(parent_rate, m, n, frac, pll);
}
-static u16 __pll_params_with_frac(unsigned long rate,
- unsigned long parent_rate,
- const struct pll_params_table *pllt,
- struct meson_clk_pll_data *pll)
+static unsigned int __pll_params_with_frac(unsigned long rate,
+ unsigned long parent_rate,
+ unsigned int m,
+ unsigned int n,
+ struct meson_clk_pll_data *pll)
{
- u16 frac_max = (1 << pll->frac.width);
- u64 val = (u64)rate * pllt->n;
+ unsigned int frac_max = (1 << pll->frac.width);
+ u64 val = (u64)rate * n;
+
+ /* Bail out if we are already over the requested rate */
+ if (rate < parent_rate * m / n)
+ return 0;
if (pll->flags & CLK_MESON_PLL_ROUND_CLOSEST)
val = DIV_ROUND_CLOSEST_ULL(val * frac_max, parent_rate);
else
val = div_u64(val * frac_max, parent_rate);
- val -= pllt->m * frac_max;
+ val -= m * frac_max;
- return min((u16)val, (u16)(frac_max - 1));
+ return min((unsigned int)val, (frac_max - 1));
}
static bool meson_clk_pll_is_better(unsigned long rate,
unsigned long now,
struct meson_clk_pll_data *pll)
{
- if (!(pll->flags & CLK_MESON_PLL_ROUND_CLOSEST) ||
- MESON_PARM_APPLICABLE(&pll->frac)) {
- /* Round down */
- if (now < rate && best < now)
- return true;
- } else {
+ if (__pll_round_closest_mult(pll)) {
/* Round Closest */
if (abs(now - rate) < abs(best - rate))
return true;
+ } else {
+ /* Round down */
+ if (now <= rate && best < now)
+ return true;
}
return false;
}
-static const struct pll_params_table *
-meson_clk_get_pll_settings(unsigned long rate,
- unsigned long parent_rate,
- struct meson_clk_pll_data *pll)
+static int meson_clk_get_pll_table_index(unsigned int index,
+ unsigned int *m,
+ unsigned int *n,
+ struct meson_clk_pll_data *pll)
{
- const struct pll_params_table *table = pll->table;
- unsigned long best = 0, now = 0;
- unsigned int i, best_i = 0;
+ if (!pll->table[index].n)
+ return -EINVAL;
+
+ *m = pll->table[index].m;
+ *n = pll->table[index].n;
- if (!table)
- return NULL;
+ return 0;
+}
+
+static unsigned int meson_clk_get_pll_range_m(unsigned long rate,
+ unsigned long parent_rate,
+ unsigned int n,
+ struct meson_clk_pll_data *pll)
+{
+ u64 val = (u64)rate * n;
+
+ if (__pll_round_closest_mult(pll))
+ return DIV_ROUND_CLOSEST_ULL(val, parent_rate);
+
+ return div_u64(val, parent_rate);
+}
+
+static int meson_clk_get_pll_range_index(unsigned long rate,
+ unsigned long parent_rate,
+ unsigned int index,
+ unsigned int *m,
+ unsigned int *n,
+ struct meson_clk_pll_data *pll)
+{
+ *n = index + 1;
+
+ /* Check the predivider range */
+ if (*n >= (1 << pll->n.width))
+ return -EINVAL;
+
+ if (*n == 1) {
+ /* Get the boundaries out the way */
+ if (rate <= pll->range->min * parent_rate) {
+ *m = pll->range->min;
+ return -ENODATA;
+ } else if (rate >= pll->range->max * parent_rate) {
+ *m = pll->range->max;
+ return -ENODATA;
+ }
+ }
- for (i = 0; table[i].n; i++) {
- now = __pll_params_to_rate(parent_rate, &table[i], 0, pll);
+ *m = meson_clk_get_pll_range_m(rate, parent_rate, *n, pll);
+
+ /* the pre-divider gives a multiplier too big - stop */
+ if (*m >= (1 << pll->m.width))
+ return -EINVAL;
- /* If we get an exact match, don't bother any further */
- if (now == rate) {
- return &table[i];
- } else if (meson_clk_pll_is_better(rate, best, now, pll)) {
+ return 0;
+}
+
+static int meson_clk_get_pll_get_index(unsigned long rate,
+ unsigned long parent_rate,
+ unsigned int index,
+ unsigned int *m,
+ unsigned int *n,
+ struct meson_clk_pll_data *pll)
+{
+ if (pll->range)
+ return meson_clk_get_pll_range_index(rate, parent_rate,
+ index, m, n, pll);
+ else if (pll->table)
+ return meson_clk_get_pll_table_index(index, m, n, pll);
+
+ return -EINVAL;
+}
+
+static int meson_clk_get_pll_settings(unsigned long rate,
+ unsigned long parent_rate,
+ unsigned int *best_m,
+ unsigned int *best_n,
+ struct meson_clk_pll_data *pll)
+{
+ unsigned long best = 0, now = 0;
+ unsigned int i, m, n;
+ int ret;
+
+ for (i = 0, ret = 0; !ret; i++) {
+ ret = meson_clk_get_pll_get_index(rate, parent_rate,
+ i, &m, &n, pll);
+ if (ret == -EINVAL)
+ break;
+
+ now = __pll_params_to_rate(parent_rate, m, n, 0, pll);
+ if (meson_clk_pll_is_better(rate, best, now, pll)) {
best = now;
- best_i = i;
+ *best_m = m;
+ *best_n = n;
+
+ if (now == rate)
+ break;
}
}
- return (struct pll_params_table *)&table[best_i];
+ return best ? 0 : -EINVAL;
}
static long meson_clk_pll_round_rate(struct clk_hw *hw, unsigned long rate,
{
struct clk_regmap *clk = to_clk_regmap(hw);
struct meson_clk_pll_data *pll = meson_clk_pll_data(clk);
- const struct pll_params_table *pllt =
- meson_clk_get_pll_settings(rate, *parent_rate, pll);
+ unsigned int m, n, frac;
unsigned long round;
- u16 frac;
+ int ret;
- if (!pllt)
+ ret = meson_clk_get_pll_settings(rate, *parent_rate, &m, &n, pll);
+ if (ret)
return meson_clk_pll_recalc_rate(hw, *parent_rate);
- round = __pll_params_to_rate(*parent_rate, pllt, 0, pll);
+ round = __pll_params_to_rate(*parent_rate, m, n, 0, pll);
if (!MESON_PARM_APPLICABLE(&pll->frac) || rate == round)
return round;
* The rate provided by the setting is not an exact match, let's
* try to improve the result using the fractional parameter
*/
- frac = __pll_params_with_frac(rate, *parent_rate, pllt, pll);
+ frac = __pll_params_with_frac(rate, *parent_rate, m, n, pll);
- return __pll_params_to_rate(*parent_rate, pllt, frac, pll);
+ return __pll_params_to_rate(*parent_rate, m, n, frac, pll);
}
static int meson_clk_pll_wait_lock(struct clk_hw *hw)
return 1;
}
+static int meson_clk_pcie_pll_enable(struct clk_hw *hw)
+{
+ meson_clk_pll_init(hw);
+
+ if (meson_clk_pll_wait_lock(hw))
+ return -EIO;
+
+ return 0;
+}
+
static int meson_clk_pll_enable(struct clk_hw *hw)
{
struct clk_regmap *clk = to_clk_regmap(hw);
{
struct clk_regmap *clk = to_clk_regmap(hw);
struct meson_clk_pll_data *pll = meson_clk_pll_data(clk);
- const struct pll_params_table *pllt;
- unsigned int enabled;
+ unsigned int enabled, m, n, frac = 0, ret;
unsigned long old_rate;
- u16 frac = 0;
if (parent_rate == 0 || rate == 0)
return -EINVAL;
old_rate = rate;
- pllt = meson_clk_get_pll_settings(rate, parent_rate, pll);
- if (!pllt)
- return -EINVAL;
+ ret = meson_clk_get_pll_settings(rate, parent_rate, &m, &n, pll);
+ if (ret)
+ return ret;
enabled = meson_parm_read(clk->map, &pll->en);
if (enabled)
meson_clk_pll_disable(hw);
- meson_parm_write(clk->map, &pll->n, pllt->n);
- meson_parm_write(clk->map, &pll->m, pllt->m);
-
+ meson_parm_write(clk->map, &pll->n, n);
+ meson_parm_write(clk->map, &pll->m, m);
if (MESON_PARM_APPLICABLE(&pll->frac)) {
- frac = __pll_params_with_frac(rate, parent_rate, pllt, pll);
+ frac = __pll_params_with_frac(rate, parent_rate, m, n, pll);
meson_parm_write(clk->map, &pll->frac, frac);
}
return 0;
}
+/*
+ * The Meson G12A PCIE PLL is fined tuned to deliver a very precise
+ * 100MHz reference clock for the PCIe Analog PHY, and thus requires
+ * a strict register sequence to enable the PLL.
+ * To simplify, re-use the _init() op to enable the PLL and keep
+ * the other ops except set_rate since the rate is fixed.
+ */
+const struct clk_ops meson_clk_pcie_pll_ops = {
+ .recalc_rate = meson_clk_pll_recalc_rate,
+ .round_rate = meson_clk_pll_round_rate,
+ .is_enabled = meson_clk_pll_is_enabled,
+ .enable = meson_clk_pcie_pll_enable,
+ .disable = meson_clk_pll_disable
+};
+EXPORT_SYMBOL_GPL(meson_clk_pcie_pll_ops);
+
const struct clk_ops meson_clk_pll_ops = {
.init = meson_clk_pll_init,
.recalc_rate = meson_clk_pll_recalc_rate,
.enable = meson_clk_pll_enable,
.disable = meson_clk_pll_disable
};
+EXPORT_SYMBOL_GPL(meson_clk_pll_ops);
const struct clk_ops meson_clk_pll_ro_ops = {
.recalc_rate = meson_clk_pll_recalc_rate,
.is_enabled = meson_clk_pll_is_enabled,
};
+EXPORT_SYMBOL_GPL(meson_clk_pll_ro_ops);
+
+MODULE_DESCRIPTION("Amlogic PLL driver");
+MODULE_AUTHOR("Carlo Caione <carlo@endlessm.com>");
+MODULE_AUTHOR("Jerome Brunet <jbrunet@baylibre.com>");
+MODULE_LICENSE("GPL v2");
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