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Diffstat (limited to 'drivers/clk/sunxi-ng/ccu_nkm.c')
-rw-r--r--drivers/clk/sunxi-ng/ccu_nkm.c208
1 files changed, 208 insertions, 0 deletions
diff --git a/drivers/clk/sunxi-ng/ccu_nkm.c b/drivers/clk/sunxi-ng/ccu_nkm.c
new file mode 100644
index 000000000..b9cfee027
--- /dev/null
+++ b/drivers/clk/sunxi-ng/ccu_nkm.c
@@ -0,0 +1,208 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2016 Maxime Ripard
+ * Maxime Ripard <maxime.ripard@free-electrons.com>
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/io.h>
+
+#include "ccu_gate.h"
+#include "ccu_nkm.h"
+
+struct _ccu_nkm {
+ unsigned long n, min_n, max_n;
+ unsigned long k, min_k, max_k;
+ unsigned long m, min_m, max_m;
+};
+
+static void ccu_nkm_find_best(unsigned long parent, unsigned long rate,
+ struct _ccu_nkm *nkm)
+{
+ unsigned long best_rate = 0;
+ unsigned long best_n = 0, best_k = 0, best_m = 0;
+ unsigned long _n, _k, _m;
+
+ for (_k = nkm->min_k; _k <= nkm->max_k; _k++) {
+ for (_n = nkm->min_n; _n <= nkm->max_n; _n++) {
+ for (_m = nkm->min_m; _m <= nkm->max_m; _m++) {
+ unsigned long tmp_rate;
+
+ tmp_rate = parent * _n * _k / _m;
+
+ if (tmp_rate > rate)
+ continue;
+ if ((rate - tmp_rate) < (rate - best_rate)) {
+ best_rate = tmp_rate;
+ best_n = _n;
+ best_k = _k;
+ best_m = _m;
+ }
+ }
+ }
+ }
+
+ nkm->n = best_n;
+ nkm->k = best_k;
+ nkm->m = best_m;
+}
+
+static void ccu_nkm_disable(struct clk_hw *hw)
+{
+ struct ccu_nkm *nkm = hw_to_ccu_nkm(hw);
+
+ return ccu_gate_helper_disable(&nkm->common, nkm->enable);
+}
+
+static int ccu_nkm_enable(struct clk_hw *hw)
+{
+ struct ccu_nkm *nkm = hw_to_ccu_nkm(hw);
+
+ return ccu_gate_helper_enable(&nkm->common, nkm->enable);
+}
+
+static int ccu_nkm_is_enabled(struct clk_hw *hw)
+{
+ struct ccu_nkm *nkm = hw_to_ccu_nkm(hw);
+
+ return ccu_gate_helper_is_enabled(&nkm->common, nkm->enable);
+}
+
+static unsigned long ccu_nkm_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct ccu_nkm *nkm = hw_to_ccu_nkm(hw);
+ unsigned long n, m, k, rate;
+ u32 reg;
+
+ reg = readl(nkm->common.base + nkm->common.reg);
+
+ n = reg >> nkm->n.shift;
+ n &= (1 << nkm->n.width) - 1;
+ n += nkm->n.offset;
+ if (!n)
+ n++;
+
+ k = reg >> nkm->k.shift;
+ k &= (1 << nkm->k.width) - 1;
+ k += nkm->k.offset;
+ if (!k)
+ k++;
+
+ m = reg >> nkm->m.shift;
+ m &= (1 << nkm->m.width) - 1;
+ m += nkm->m.offset;
+ if (!m)
+ m++;
+
+ rate = parent_rate * n * k / m;
+
+ if (nkm->common.features & CCU_FEATURE_FIXED_POSTDIV)
+ rate /= nkm->fixed_post_div;
+
+ return rate;
+}
+
+static unsigned long ccu_nkm_round_rate(struct ccu_mux_internal *mux,
+ struct clk_hw *hw,
+ unsigned long *parent_rate,
+ unsigned long rate,
+ void *data)
+{
+ struct ccu_nkm *nkm = data;
+ struct _ccu_nkm _nkm;
+
+ _nkm.min_n = nkm->n.min ?: 1;
+ _nkm.max_n = nkm->n.max ?: 1 << nkm->n.width;
+ _nkm.min_k = nkm->k.min ?: 1;
+ _nkm.max_k = nkm->k.max ?: 1 << nkm->k.width;
+ _nkm.min_m = 1;
+ _nkm.max_m = nkm->m.max ?: 1 << nkm->m.width;
+
+ if (nkm->common.features & CCU_FEATURE_FIXED_POSTDIV)
+ rate *= nkm->fixed_post_div;
+
+ ccu_nkm_find_best(*parent_rate, rate, &_nkm);
+
+ rate = *parent_rate * _nkm.n * _nkm.k / _nkm.m;
+
+ if (nkm->common.features & CCU_FEATURE_FIXED_POSTDIV)
+ rate /= nkm->fixed_post_div;
+
+ return rate;
+}
+
+static int ccu_nkm_determine_rate(struct clk_hw *hw,
+ struct clk_rate_request *req)
+{
+ struct ccu_nkm *nkm = hw_to_ccu_nkm(hw);
+
+ return ccu_mux_helper_determine_rate(&nkm->common, &nkm->mux,
+ req, ccu_nkm_round_rate, nkm);
+}
+
+static int ccu_nkm_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct ccu_nkm *nkm = hw_to_ccu_nkm(hw);
+ struct _ccu_nkm _nkm;
+ unsigned long flags;
+ u32 reg;
+
+ if (nkm->common.features & CCU_FEATURE_FIXED_POSTDIV)
+ rate *= nkm->fixed_post_div;
+
+ _nkm.min_n = nkm->n.min ?: 1;
+ _nkm.max_n = nkm->n.max ?: 1 << nkm->n.width;
+ _nkm.min_k = nkm->k.min ?: 1;
+ _nkm.max_k = nkm->k.max ?: 1 << nkm->k.width;
+ _nkm.min_m = 1;
+ _nkm.max_m = nkm->m.max ?: 1 << nkm->m.width;
+
+ ccu_nkm_find_best(parent_rate, rate, &_nkm);
+
+ spin_lock_irqsave(nkm->common.lock, flags);
+
+ reg = readl(nkm->common.base + nkm->common.reg);
+ reg &= ~GENMASK(nkm->n.width + nkm->n.shift - 1, nkm->n.shift);
+ reg &= ~GENMASK(nkm->k.width + nkm->k.shift - 1, nkm->k.shift);
+ reg &= ~GENMASK(nkm->m.width + nkm->m.shift - 1, nkm->m.shift);
+
+ reg |= (_nkm.n - nkm->n.offset) << nkm->n.shift;
+ reg |= (_nkm.k - nkm->k.offset) << nkm->k.shift;
+ reg |= (_nkm.m - nkm->m.offset) << nkm->m.shift;
+ writel(reg, nkm->common.base + nkm->common.reg);
+
+ spin_unlock_irqrestore(nkm->common.lock, flags);
+
+ ccu_helper_wait_for_lock(&nkm->common, nkm->lock);
+
+ return 0;
+}
+
+static u8 ccu_nkm_get_parent(struct clk_hw *hw)
+{
+ struct ccu_nkm *nkm = hw_to_ccu_nkm(hw);
+
+ return ccu_mux_helper_get_parent(&nkm->common, &nkm->mux);
+}
+
+static int ccu_nkm_set_parent(struct clk_hw *hw, u8 index)
+{
+ struct ccu_nkm *nkm = hw_to_ccu_nkm(hw);
+
+ return ccu_mux_helper_set_parent(&nkm->common, &nkm->mux, index);
+}
+
+const struct clk_ops ccu_nkm_ops = {
+ .disable = ccu_nkm_disable,
+ .enable = ccu_nkm_enable,
+ .is_enabled = ccu_nkm_is_enabled,
+
+ .get_parent = ccu_nkm_get_parent,
+ .set_parent = ccu_nkm_set_parent,
+
+ .determine_rate = ccu_nkm_determine_rate,
+ .recalc_rate = ccu_nkm_recalc_rate,
+ .set_rate = ccu_nkm_set_rate,
+};