[Feature]add MT2731_MP2_MR2_SVN388 baseline version
Change-Id: Ief04314834b31e27effab435d3ca8ba33b499059
diff --git a/src/kernel/linux/v4.14/drivers/clk/bcm/clk-kona.c b/src/kernel/linux/v4.14/drivers/clk/bcm/clk-kona.c
new file mode 100644
index 0000000..eee64b9
--- /dev/null
+++ b/src/kernel/linux/v4.14/drivers/clk/bcm/clk-kona.c
@@ -0,0 +1,1277 @@
+/*
+ * Copyright (C) 2013 Broadcom Corporation
+ * Copyright 2013 Linaro Limited
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation version 2.
+ *
+ * This program is distributed "as is" WITHOUT ANY WARRANTY of any
+ * kind, whether express or implied; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include "clk-kona.h"
+
+#include <linux/delay.h>
+#include <linux/kernel.h>
+#include <linux/clk.h>
+
+/*
+ * "Policies" affect the frequencies of bus clocks provided by a
+ * CCU. (I believe these polices are named "Deep Sleep", "Economy",
+ * "Normal", and "Turbo".) A lower policy number has lower power
+ * consumption, and policy 2 is the default.
+ */
+#define CCU_POLICY_COUNT 4
+
+#define CCU_ACCESS_PASSWORD 0xA5A500
+#define CLK_GATE_DELAY_LOOP 2000
+
+/* Bitfield operations */
+
+/* Produces a mask of set bits covering a range of a 32-bit value */
+static inline u32 bitfield_mask(u32 shift, u32 width)
+{
+ return ((1 << width) - 1) << shift;
+}
+
+/* Extract the value of a bitfield found within a given register value */
+static inline u32 bitfield_extract(u32 reg_val, u32 shift, u32 width)
+{
+ return (reg_val & bitfield_mask(shift, width)) >> shift;
+}
+
+/* Replace the value of a bitfield found within a given register value */
+static inline u32 bitfield_replace(u32 reg_val, u32 shift, u32 width, u32 val)
+{
+ u32 mask = bitfield_mask(shift, width);
+
+ return (reg_val & ~mask) | (val << shift);
+}
+
+/* Divider and scaling helpers */
+
+/* Convert a divider into the scaled divisor value it represents. */
+static inline u64 scaled_div_value(struct bcm_clk_div *div, u32 reg_div)
+{
+ return (u64)reg_div + ((u64)1 << div->u.s.frac_width);
+}
+
+/*
+ * Build a scaled divider value as close as possible to the
+ * given whole part (div_value) and fractional part (expressed
+ * in billionths).
+ */
+u64 scaled_div_build(struct bcm_clk_div *div, u32 div_value, u32 billionths)
+{
+ u64 combined;
+
+ BUG_ON(!div_value);
+ BUG_ON(billionths >= BILLION);
+
+ combined = (u64)div_value * BILLION + billionths;
+ combined <<= div->u.s.frac_width;
+
+ return DIV_ROUND_CLOSEST_ULL(combined, BILLION);
+}
+
+/* The scaled minimum divisor representable by a divider */
+static inline u64
+scaled_div_min(struct bcm_clk_div *div)
+{
+ if (divider_is_fixed(div))
+ return (u64)div->u.fixed;
+
+ return scaled_div_value(div, 0);
+}
+
+/* The scaled maximum divisor representable by a divider */
+u64 scaled_div_max(struct bcm_clk_div *div)
+{
+ u32 reg_div;
+
+ if (divider_is_fixed(div))
+ return (u64)div->u.fixed;
+
+ reg_div = ((u32)1 << div->u.s.width) - 1;
+
+ return scaled_div_value(div, reg_div);
+}
+
+/*
+ * Convert a scaled divisor into its divider representation as
+ * stored in a divider register field.
+ */
+static inline u32
+divider(struct bcm_clk_div *div, u64 scaled_div)
+{
+ BUG_ON(scaled_div < scaled_div_min(div));
+ BUG_ON(scaled_div > scaled_div_max(div));
+
+ return (u32)(scaled_div - ((u64)1 << div->u.s.frac_width));
+}
+
+/* Return a rate scaled for use when dividing by a scaled divisor. */
+static inline u64
+scale_rate(struct bcm_clk_div *div, u32 rate)
+{
+ if (divider_is_fixed(div))
+ return (u64)rate;
+
+ return (u64)rate << div->u.s.frac_width;
+}
+
+/* CCU access */
+
+/* Read a 32-bit register value from a CCU's address space. */
+static inline u32 __ccu_read(struct ccu_data *ccu, u32 reg_offset)
+{
+ return readl(ccu->base + reg_offset);
+}
+
+/* Write a 32-bit register value into a CCU's address space. */
+static inline void
+__ccu_write(struct ccu_data *ccu, u32 reg_offset, u32 reg_val)
+{
+ writel(reg_val, ccu->base + reg_offset);
+}
+
+static inline unsigned long ccu_lock(struct ccu_data *ccu)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&ccu->lock, flags);
+
+ return flags;
+}
+static inline void ccu_unlock(struct ccu_data *ccu, unsigned long flags)
+{
+ spin_unlock_irqrestore(&ccu->lock, flags);
+}
+
+/*
+ * Enable/disable write access to CCU protected registers. The
+ * WR_ACCESS register for all CCUs is at offset 0.
+ */
+static inline void __ccu_write_enable(struct ccu_data *ccu)
+{
+ if (ccu->write_enabled) {
+ pr_err("%s: access already enabled for %s\n", __func__,
+ ccu->name);
+ return;
+ }
+ ccu->write_enabled = true;
+ __ccu_write(ccu, 0, CCU_ACCESS_PASSWORD | 1);
+}
+
+static inline void __ccu_write_disable(struct ccu_data *ccu)
+{
+ if (!ccu->write_enabled) {
+ pr_err("%s: access wasn't enabled for %s\n", __func__,
+ ccu->name);
+ return;
+ }
+
+ __ccu_write(ccu, 0, CCU_ACCESS_PASSWORD);
+ ccu->write_enabled = false;
+}
+
+/*
+ * Poll a register in a CCU's address space, returning when the
+ * specified bit in that register's value is set (or clear). Delay
+ * a microsecond after each read of the register. Returns true if
+ * successful, or false if we gave up trying.
+ *
+ * Caller must ensure the CCU lock is held.
+ */
+static inline bool
+__ccu_wait_bit(struct ccu_data *ccu, u32 reg_offset, u32 bit, bool want)
+{
+ unsigned int tries;
+ u32 bit_mask = 1 << bit;
+
+ for (tries = 0; tries < CLK_GATE_DELAY_LOOP; tries++) {
+ u32 val;
+ bool bit_val;
+
+ val = __ccu_read(ccu, reg_offset);
+ bit_val = (val & bit_mask) != 0;
+ if (bit_val == want)
+ return true;
+ udelay(1);
+ }
+ pr_warn("%s: %s/0x%04x bit %u was never %s\n", __func__,
+ ccu->name, reg_offset, bit, want ? "set" : "clear");
+
+ return false;
+}
+
+/* Policy operations */
+
+static bool __ccu_policy_engine_start(struct ccu_data *ccu, bool sync)
+{
+ struct bcm_policy_ctl *control = &ccu->policy.control;
+ u32 offset;
+ u32 go_bit;
+ u32 mask;
+ bool ret;
+
+ /* If we don't need to control policy for this CCU, we're done. */
+ if (!policy_ctl_exists(control))
+ return true;
+
+ offset = control->offset;
+ go_bit = control->go_bit;
+
+ /* Ensure we're not busy before we start */
+ ret = __ccu_wait_bit(ccu, offset, go_bit, false);
+ if (!ret) {
+ pr_err("%s: ccu %s policy engine wouldn't go idle\n",
+ __func__, ccu->name);
+ return false;
+ }
+
+ /*
+ * If it's a synchronous request, we'll wait for the voltage
+ * and frequency of the active load to stabilize before
+ * returning. To do this we select the active load by
+ * setting the ATL bit.
+ *
+ * An asynchronous request instead ramps the voltage in the
+ * background, and when that process stabilizes, the target
+ * load is copied to the active load and the CCU frequency
+ * is switched. We do this by selecting the target load
+ * (ATL bit clear) and setting the request auto-copy (AC bit
+ * set).
+ *
+ * Note, we do NOT read-modify-write this register.
+ */
+ mask = (u32)1 << go_bit;
+ if (sync)
+ mask |= 1 << control->atl_bit;
+ else
+ mask |= 1 << control->ac_bit;
+ __ccu_write(ccu, offset, mask);
+
+ /* Wait for indication that operation is complete. */
+ ret = __ccu_wait_bit(ccu, offset, go_bit, false);
+ if (!ret)
+ pr_err("%s: ccu %s policy engine never started\n",
+ __func__, ccu->name);
+
+ return ret;
+}
+
+static bool __ccu_policy_engine_stop(struct ccu_data *ccu)
+{
+ struct bcm_lvm_en *enable = &ccu->policy.enable;
+ u32 offset;
+ u32 enable_bit;
+ bool ret;
+
+ /* If we don't need to control policy for this CCU, we're done. */
+ if (!policy_lvm_en_exists(enable))
+ return true;
+
+ /* Ensure we're not busy before we start */
+ offset = enable->offset;
+ enable_bit = enable->bit;
+ ret = __ccu_wait_bit(ccu, offset, enable_bit, false);
+ if (!ret) {
+ pr_err("%s: ccu %s policy engine already stopped\n",
+ __func__, ccu->name);
+ return false;
+ }
+
+ /* Now set the bit to stop the engine (NO read-modify-write) */
+ __ccu_write(ccu, offset, (u32)1 << enable_bit);
+
+ /* Wait for indication that it has stopped. */
+ ret = __ccu_wait_bit(ccu, offset, enable_bit, false);
+ if (!ret)
+ pr_err("%s: ccu %s policy engine never stopped\n",
+ __func__, ccu->name);
+
+ return ret;
+}
+
+/*
+ * A CCU has four operating conditions ("policies"), and some clocks
+ * can be disabled or enabled based on which policy is currently in
+ * effect. Such clocks have a bit in a "policy mask" register for
+ * each policy indicating whether the clock is enabled for that
+ * policy or not. The bit position for a clock is the same for all
+ * four registers, and the 32-bit registers are at consecutive
+ * addresses.
+ */
+static bool policy_init(struct ccu_data *ccu, struct bcm_clk_policy *policy)
+{
+ u32 offset;
+ u32 mask;
+ int i;
+ bool ret;
+
+ if (!policy_exists(policy))
+ return true;
+
+ /*
+ * We need to stop the CCU policy engine to allow update
+ * of our policy bits.
+ */
+ if (!__ccu_policy_engine_stop(ccu)) {
+ pr_err("%s: unable to stop CCU %s policy engine\n",
+ __func__, ccu->name);
+ return false;
+ }
+
+ /*
+ * For now, if a clock defines its policy bit we just mark
+ * it "enabled" for all four policies.
+ */
+ offset = policy->offset;
+ mask = (u32)1 << policy->bit;
+ for (i = 0; i < CCU_POLICY_COUNT; i++) {
+ u32 reg_val;
+
+ reg_val = __ccu_read(ccu, offset);
+ reg_val |= mask;
+ __ccu_write(ccu, offset, reg_val);
+ offset += sizeof(u32);
+ }
+
+ /* We're done updating; fire up the policy engine again. */
+ ret = __ccu_policy_engine_start(ccu, true);
+ if (!ret)
+ pr_err("%s: unable to restart CCU %s policy engine\n",
+ __func__, ccu->name);
+
+ return ret;
+}
+
+/* Gate operations */
+
+/* Determine whether a clock is gated. CCU lock must be held. */
+static bool
+__is_clk_gate_enabled(struct ccu_data *ccu, struct bcm_clk_gate *gate)
+{
+ u32 bit_mask;
+ u32 reg_val;
+
+ /* If there is no gate we can assume it's enabled. */
+ if (!gate_exists(gate))
+ return true;
+
+ bit_mask = 1 << gate->status_bit;
+ reg_val = __ccu_read(ccu, gate->offset);
+
+ return (reg_val & bit_mask) != 0;
+}
+
+/* Determine whether a clock is gated. */
+static bool
+is_clk_gate_enabled(struct ccu_data *ccu, struct bcm_clk_gate *gate)
+{
+ long flags;
+ bool ret;
+
+ /* Avoid taking the lock if we can */
+ if (!gate_exists(gate))
+ return true;
+
+ flags = ccu_lock(ccu);
+ ret = __is_clk_gate_enabled(ccu, gate);
+ ccu_unlock(ccu, flags);
+
+ return ret;
+}
+
+/*
+ * Commit our desired gate state to the hardware.
+ * Returns true if successful, false otherwise.
+ */
+static bool
+__gate_commit(struct ccu_data *ccu, struct bcm_clk_gate *gate)
+{
+ u32 reg_val;
+ u32 mask;
+ bool enabled = false;
+
+ BUG_ON(!gate_exists(gate));
+ if (!gate_is_sw_controllable(gate))
+ return true; /* Nothing we can change */
+
+ reg_val = __ccu_read(ccu, gate->offset);
+
+ /* For a hardware/software gate, set which is in control */
+ if (gate_is_hw_controllable(gate)) {
+ mask = (u32)1 << gate->hw_sw_sel_bit;
+ if (gate_is_sw_managed(gate))
+ reg_val |= mask;
+ else
+ reg_val &= ~mask;
+ }
+
+ /*
+ * If software is in control, enable or disable the gate.
+ * If hardware is, clear the enabled bit for good measure.
+ * If a software controlled gate can't be disabled, we're
+ * required to write a 0 into the enable bit (but the gate
+ * will be enabled).
+ */
+ mask = (u32)1 << gate->en_bit;
+ if (gate_is_sw_managed(gate) && (enabled = gate_is_enabled(gate)) &&
+ !gate_is_no_disable(gate))
+ reg_val |= mask;
+ else
+ reg_val &= ~mask;
+
+ __ccu_write(ccu, gate->offset, reg_val);
+
+ /* For a hardware controlled gate, we're done */
+ if (!gate_is_sw_managed(gate))
+ return true;
+
+ /* Otherwise wait for the gate to be in desired state */
+ return __ccu_wait_bit(ccu, gate->offset, gate->status_bit, enabled);
+}
+
+/*
+ * Initialize a gate. Our desired state (hardware/software select,
+ * and if software, its enable state) is committed to hardware
+ * without the usual checks to see if it's already set up that way.
+ * Returns true if successful, false otherwise.
+ */
+static bool gate_init(struct ccu_data *ccu, struct bcm_clk_gate *gate)
+{
+ if (!gate_exists(gate))
+ return true;
+ return __gate_commit(ccu, gate);
+}
+
+/*
+ * Set a gate to enabled or disabled state. Does nothing if the
+ * gate is not currently under software control, or if it is already
+ * in the requested state. Returns true if successful, false
+ * otherwise. CCU lock must be held.
+ */
+static bool
+__clk_gate(struct ccu_data *ccu, struct bcm_clk_gate *gate, bool enable)
+{
+ bool ret;
+
+ if (!gate_exists(gate) || !gate_is_sw_managed(gate))
+ return true; /* Nothing to do */
+
+ if (!enable && gate_is_no_disable(gate)) {
+ pr_warn("%s: invalid gate disable request (ignoring)\n",
+ __func__);
+ return true;
+ }
+
+ if (enable == gate_is_enabled(gate))
+ return true; /* No change */
+
+ gate_flip_enabled(gate);
+ ret = __gate_commit(ccu, gate);
+ if (!ret)
+ gate_flip_enabled(gate); /* Revert the change */
+
+ return ret;
+}
+
+/* Enable or disable a gate. Returns 0 if successful, -EIO otherwise */
+static int clk_gate(struct ccu_data *ccu, const char *name,
+ struct bcm_clk_gate *gate, bool enable)
+{
+ unsigned long flags;
+ bool success;
+
+ /*
+ * Avoid taking the lock if we can. We quietly ignore
+ * requests to change state that don't make sense.
+ */
+ if (!gate_exists(gate) || !gate_is_sw_managed(gate))
+ return 0;
+ if (!enable && gate_is_no_disable(gate))
+ return 0;
+
+ flags = ccu_lock(ccu);
+ __ccu_write_enable(ccu);
+
+ success = __clk_gate(ccu, gate, enable);
+
+ __ccu_write_disable(ccu);
+ ccu_unlock(ccu, flags);
+
+ if (success)
+ return 0;
+
+ pr_err("%s: failed to %s gate for %s\n", __func__,
+ enable ? "enable" : "disable", name);
+
+ return -EIO;
+}
+
+/* Hysteresis operations */
+
+/*
+ * If a clock gate requires a turn-off delay it will have
+ * "hysteresis" register bits defined. The first, if set, enables
+ * the delay; and if enabled, the second bit determines whether the
+ * delay is "low" or "high" (1 means high). For now, if it's
+ * defined for a clock, we set it.
+ */
+static bool hyst_init(struct ccu_data *ccu, struct bcm_clk_hyst *hyst)
+{
+ u32 offset;
+ u32 reg_val;
+ u32 mask;
+
+ if (!hyst_exists(hyst))
+ return true;
+
+ offset = hyst->offset;
+ mask = (u32)1 << hyst->en_bit;
+ mask |= (u32)1 << hyst->val_bit;
+
+ reg_val = __ccu_read(ccu, offset);
+ reg_val |= mask;
+ __ccu_write(ccu, offset, reg_val);
+
+ return true;
+}
+
+/* Trigger operations */
+
+/*
+ * Caller must ensure CCU lock is held and access is enabled.
+ * Returns true if successful, false otherwise.
+ */
+static bool __clk_trigger(struct ccu_data *ccu, struct bcm_clk_trig *trig)
+{
+ /* Trigger the clock and wait for it to finish */
+ __ccu_write(ccu, trig->offset, 1 << trig->bit);
+
+ return __ccu_wait_bit(ccu, trig->offset, trig->bit, false);
+}
+
+/* Divider operations */
+
+/* Read a divider value and return the scaled divisor it represents. */
+static u64 divider_read_scaled(struct ccu_data *ccu, struct bcm_clk_div *div)
+{
+ unsigned long flags;
+ u32 reg_val;
+ u32 reg_div;
+
+ if (divider_is_fixed(div))
+ return (u64)div->u.fixed;
+
+ flags = ccu_lock(ccu);
+ reg_val = __ccu_read(ccu, div->u.s.offset);
+ ccu_unlock(ccu, flags);
+
+ /* Extract the full divider field from the register value */
+ reg_div = bitfield_extract(reg_val, div->u.s.shift, div->u.s.width);
+
+ /* Return the scaled divisor value it represents */
+ return scaled_div_value(div, reg_div);
+}
+
+/*
+ * Convert a divider's scaled divisor value into its recorded form
+ * and commit it into the hardware divider register.
+ *
+ * Returns 0 on success. Returns -EINVAL for invalid arguments.
+ * Returns -ENXIO if gating failed, and -EIO if a trigger failed.
+ */
+static int __div_commit(struct ccu_data *ccu, struct bcm_clk_gate *gate,
+ struct bcm_clk_div *div, struct bcm_clk_trig *trig)
+{
+ bool enabled;
+ u32 reg_div;
+ u32 reg_val;
+ int ret = 0;
+
+ BUG_ON(divider_is_fixed(div));
+
+ /*
+ * If we're just initializing the divider, and no initial
+ * state was defined in the device tree, we just find out
+ * what its current value is rather than updating it.
+ */
+ if (div->u.s.scaled_div == BAD_SCALED_DIV_VALUE) {
+ reg_val = __ccu_read(ccu, div->u.s.offset);
+ reg_div = bitfield_extract(reg_val, div->u.s.shift,
+ div->u.s.width);
+ div->u.s.scaled_div = scaled_div_value(div, reg_div);
+
+ return 0;
+ }
+
+ /* Convert the scaled divisor to the value we need to record */
+ reg_div = divider(div, div->u.s.scaled_div);
+
+ /* Clock needs to be enabled before changing the rate */
+ enabled = __is_clk_gate_enabled(ccu, gate);
+ if (!enabled && !__clk_gate(ccu, gate, true)) {
+ ret = -ENXIO;
+ goto out;
+ }
+
+ /* Replace the divider value and record the result */
+ reg_val = __ccu_read(ccu, div->u.s.offset);
+ reg_val = bitfield_replace(reg_val, div->u.s.shift, div->u.s.width,
+ reg_div);
+ __ccu_write(ccu, div->u.s.offset, reg_val);
+
+ /* If the trigger fails we still want to disable the gate */
+ if (!__clk_trigger(ccu, trig))
+ ret = -EIO;
+
+ /* Disable the clock again if it was disabled to begin with */
+ if (!enabled && !__clk_gate(ccu, gate, false))
+ ret = ret ? ret : -ENXIO; /* return first error */
+out:
+ return ret;
+}
+
+/*
+ * Initialize a divider by committing our desired state to hardware
+ * without the usual checks to see if it's already set up that way.
+ * Returns true if successful, false otherwise.
+ */
+static bool div_init(struct ccu_data *ccu, struct bcm_clk_gate *gate,
+ struct bcm_clk_div *div, struct bcm_clk_trig *trig)
+{
+ if (!divider_exists(div) || divider_is_fixed(div))
+ return true;
+ return !__div_commit(ccu, gate, div, trig);
+}
+
+static int divider_write(struct ccu_data *ccu, struct bcm_clk_gate *gate,
+ struct bcm_clk_div *div, struct bcm_clk_trig *trig,
+ u64 scaled_div)
+{
+ unsigned long flags;
+ u64 previous;
+ int ret;
+
+ BUG_ON(divider_is_fixed(div));
+
+ previous = div->u.s.scaled_div;
+ if (previous == scaled_div)
+ return 0; /* No change */
+
+ div->u.s.scaled_div = scaled_div;
+
+ flags = ccu_lock(ccu);
+ __ccu_write_enable(ccu);
+
+ ret = __div_commit(ccu, gate, div, trig);
+
+ __ccu_write_disable(ccu);
+ ccu_unlock(ccu, flags);
+
+ if (ret)
+ div->u.s.scaled_div = previous; /* Revert the change */
+
+ return ret;
+
+}
+
+/* Common clock rate helpers */
+
+/*
+ * Implement the common clock framework recalc_rate method, taking
+ * into account a divider and an optional pre-divider. The
+ * pre-divider register pointer may be NULL.
+ */
+static unsigned long clk_recalc_rate(struct ccu_data *ccu,
+ struct bcm_clk_div *div, struct bcm_clk_div *pre_div,
+ unsigned long parent_rate)
+{
+ u64 scaled_parent_rate;
+ u64 scaled_div;
+ u64 result;
+
+ if (!divider_exists(div))
+ return parent_rate;
+
+ if (parent_rate > (unsigned long)LONG_MAX)
+ return 0; /* actually this would be a caller bug */
+
+ /*
+ * If there is a pre-divider, divide the scaled parent rate
+ * by the pre-divider value first. In this case--to improve
+ * accuracy--scale the parent rate by *both* the pre-divider
+ * value and the divider before actually computing the
+ * result of the pre-divider.
+ *
+ * If there's only one divider, just scale the parent rate.
+ */
+ if (pre_div && divider_exists(pre_div)) {
+ u64 scaled_rate;
+
+ scaled_rate = scale_rate(pre_div, parent_rate);
+ scaled_rate = scale_rate(div, scaled_rate);
+ scaled_div = divider_read_scaled(ccu, pre_div);
+ scaled_parent_rate = DIV_ROUND_CLOSEST_ULL(scaled_rate,
+ scaled_div);
+ } else {
+ scaled_parent_rate = scale_rate(div, parent_rate);
+ }
+
+ /*
+ * Get the scaled divisor value, and divide the scaled
+ * parent rate by that to determine this clock's resulting
+ * rate.
+ */
+ scaled_div = divider_read_scaled(ccu, div);
+ result = DIV_ROUND_CLOSEST_ULL(scaled_parent_rate, scaled_div);
+
+ return (unsigned long)result;
+}
+
+/*
+ * Compute the output rate produced when a given parent rate is fed
+ * into two dividers. The pre-divider can be NULL, and even if it's
+ * non-null it may be nonexistent. It's also OK for the divider to
+ * be nonexistent, and in that case the pre-divider is also ignored.
+ *
+ * If scaled_div is non-null, it is used to return the scaled divisor
+ * value used by the (downstream) divider to produce that rate.
+ */
+static long round_rate(struct ccu_data *ccu, struct bcm_clk_div *div,
+ struct bcm_clk_div *pre_div,
+ unsigned long rate, unsigned long parent_rate,
+ u64 *scaled_div)
+{
+ u64 scaled_parent_rate;
+ u64 min_scaled_div;
+ u64 max_scaled_div;
+ u64 best_scaled_div;
+ u64 result;
+
+ BUG_ON(!divider_exists(div));
+ BUG_ON(!rate);
+ BUG_ON(parent_rate > (u64)LONG_MAX);
+
+ /*
+ * If there is a pre-divider, divide the scaled parent rate
+ * by the pre-divider value first. In this case--to improve
+ * accuracy--scale the parent rate by *both* the pre-divider
+ * value and the divider before actually computing the
+ * result of the pre-divider.
+ *
+ * If there's only one divider, just scale the parent rate.
+ *
+ * For simplicity we treat the pre-divider as fixed (for now).
+ */
+ if (divider_exists(pre_div)) {
+ u64 scaled_rate;
+ u64 scaled_pre_div;
+
+ scaled_rate = scale_rate(pre_div, parent_rate);
+ scaled_rate = scale_rate(div, scaled_rate);
+ scaled_pre_div = divider_read_scaled(ccu, pre_div);
+ scaled_parent_rate = DIV_ROUND_CLOSEST_ULL(scaled_rate,
+ scaled_pre_div);
+ } else {
+ scaled_parent_rate = scale_rate(div, parent_rate);
+ }
+
+ /*
+ * Compute the best possible divider and ensure it is in
+ * range. A fixed divider can't be changed, so just report
+ * the best we can do.
+ */
+ if (!divider_is_fixed(div)) {
+ best_scaled_div = DIV_ROUND_CLOSEST_ULL(scaled_parent_rate,
+ rate);
+ min_scaled_div = scaled_div_min(div);
+ max_scaled_div = scaled_div_max(div);
+ if (best_scaled_div > max_scaled_div)
+ best_scaled_div = max_scaled_div;
+ else if (best_scaled_div < min_scaled_div)
+ best_scaled_div = min_scaled_div;
+ } else {
+ best_scaled_div = divider_read_scaled(ccu, div);
+ }
+
+ /* OK, figure out the resulting rate */
+ result = DIV_ROUND_CLOSEST_ULL(scaled_parent_rate, best_scaled_div);
+
+ if (scaled_div)
+ *scaled_div = best_scaled_div;
+
+ return (long)result;
+}
+
+/* Common clock parent helpers */
+
+/*
+ * For a given parent selector (register field) value, find the
+ * index into a selector's parent_sel array that contains it.
+ * Returns the index, or BAD_CLK_INDEX if it's not found.
+ */
+static u8 parent_index(struct bcm_clk_sel *sel, u8 parent_sel)
+{
+ u8 i;
+
+ BUG_ON(sel->parent_count > (u32)U8_MAX);
+ for (i = 0; i < sel->parent_count; i++)
+ if (sel->parent_sel[i] == parent_sel)
+ return i;
+ return BAD_CLK_INDEX;
+}
+
+/*
+ * Fetch the current value of the selector, and translate that into
+ * its corresponding index in the parent array we registered with
+ * the clock framework.
+ *
+ * Returns parent array index that corresponds with the value found,
+ * or BAD_CLK_INDEX if the found value is out of range.
+ */
+static u8 selector_read_index(struct ccu_data *ccu, struct bcm_clk_sel *sel)
+{
+ unsigned long flags;
+ u32 reg_val;
+ u32 parent_sel;
+ u8 index;
+
+ /* If there's no selector, there's only one parent */
+ if (!selector_exists(sel))
+ return 0;
+
+ /* Get the value in the selector register */
+ flags = ccu_lock(ccu);
+ reg_val = __ccu_read(ccu, sel->offset);
+ ccu_unlock(ccu, flags);
+
+ parent_sel = bitfield_extract(reg_val, sel->shift, sel->width);
+
+ /* Look up that selector's parent array index and return it */
+ index = parent_index(sel, parent_sel);
+ if (index == BAD_CLK_INDEX)
+ pr_err("%s: out-of-range parent selector %u (%s 0x%04x)\n",
+ __func__, parent_sel, ccu->name, sel->offset);
+
+ return index;
+}
+
+/*
+ * Commit our desired selector value to the hardware.
+ *
+ * Returns 0 on success. Returns -EINVAL for invalid arguments.
+ * Returns -ENXIO if gating failed, and -EIO if a trigger failed.
+ */
+static int
+__sel_commit(struct ccu_data *ccu, struct bcm_clk_gate *gate,
+ struct bcm_clk_sel *sel, struct bcm_clk_trig *trig)
+{
+ u32 parent_sel;
+ u32 reg_val;
+ bool enabled;
+ int ret = 0;
+
+ BUG_ON(!selector_exists(sel));
+
+ /*
+ * If we're just initializing the selector, and no initial
+ * state was defined in the device tree, we just find out
+ * what its current value is rather than updating it.
+ */
+ if (sel->clk_index == BAD_CLK_INDEX) {
+ u8 index;
+
+ reg_val = __ccu_read(ccu, sel->offset);
+ parent_sel = bitfield_extract(reg_val, sel->shift, sel->width);
+ index = parent_index(sel, parent_sel);
+ if (index == BAD_CLK_INDEX)
+ return -EINVAL;
+ sel->clk_index = index;
+
+ return 0;
+ }
+
+ BUG_ON((u32)sel->clk_index >= sel->parent_count);
+ parent_sel = sel->parent_sel[sel->clk_index];
+
+ /* Clock needs to be enabled before changing the parent */
+ enabled = __is_clk_gate_enabled(ccu, gate);
+ if (!enabled && !__clk_gate(ccu, gate, true))
+ return -ENXIO;
+
+ /* Replace the selector value and record the result */
+ reg_val = __ccu_read(ccu, sel->offset);
+ reg_val = bitfield_replace(reg_val, sel->shift, sel->width, parent_sel);
+ __ccu_write(ccu, sel->offset, reg_val);
+
+ /* If the trigger fails we still want to disable the gate */
+ if (!__clk_trigger(ccu, trig))
+ ret = -EIO;
+
+ /* Disable the clock again if it was disabled to begin with */
+ if (!enabled && !__clk_gate(ccu, gate, false))
+ ret = ret ? ret : -ENXIO; /* return first error */
+
+ return ret;
+}
+
+/*
+ * Initialize a selector by committing our desired state to hardware
+ * without the usual checks to see if it's already set up that way.
+ * Returns true if successful, false otherwise.
+ */
+static bool sel_init(struct ccu_data *ccu, struct bcm_clk_gate *gate,
+ struct bcm_clk_sel *sel, struct bcm_clk_trig *trig)
+{
+ if (!selector_exists(sel))
+ return true;
+ return !__sel_commit(ccu, gate, sel, trig);
+}
+
+/*
+ * Write a new value into a selector register to switch to a
+ * different parent clock. Returns 0 on success, or an error code
+ * (from __sel_commit()) otherwise.
+ */
+static int selector_write(struct ccu_data *ccu, struct bcm_clk_gate *gate,
+ struct bcm_clk_sel *sel, struct bcm_clk_trig *trig,
+ u8 index)
+{
+ unsigned long flags;
+ u8 previous;
+ int ret;
+
+ previous = sel->clk_index;
+ if (previous == index)
+ return 0; /* No change */
+
+ sel->clk_index = index;
+
+ flags = ccu_lock(ccu);
+ __ccu_write_enable(ccu);
+
+ ret = __sel_commit(ccu, gate, sel, trig);
+
+ __ccu_write_disable(ccu);
+ ccu_unlock(ccu, flags);
+
+ if (ret)
+ sel->clk_index = previous; /* Revert the change */
+
+ return ret;
+}
+
+/* Clock operations */
+
+static int kona_peri_clk_enable(struct clk_hw *hw)
+{
+ struct kona_clk *bcm_clk = to_kona_clk(hw);
+ struct bcm_clk_gate *gate = &bcm_clk->u.peri->gate;
+
+ return clk_gate(bcm_clk->ccu, bcm_clk->init_data.name, gate, true);
+}
+
+static void kona_peri_clk_disable(struct clk_hw *hw)
+{
+ struct kona_clk *bcm_clk = to_kona_clk(hw);
+ struct bcm_clk_gate *gate = &bcm_clk->u.peri->gate;
+
+ (void)clk_gate(bcm_clk->ccu, bcm_clk->init_data.name, gate, false);
+}
+
+static int kona_peri_clk_is_enabled(struct clk_hw *hw)
+{
+ struct kona_clk *bcm_clk = to_kona_clk(hw);
+ struct bcm_clk_gate *gate = &bcm_clk->u.peri->gate;
+
+ return is_clk_gate_enabled(bcm_clk->ccu, gate) ? 1 : 0;
+}
+
+static unsigned long kona_peri_clk_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct kona_clk *bcm_clk = to_kona_clk(hw);
+ struct peri_clk_data *data = bcm_clk->u.peri;
+
+ return clk_recalc_rate(bcm_clk->ccu, &data->div, &data->pre_div,
+ parent_rate);
+}
+
+static long kona_peri_clk_round_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long *parent_rate)
+{
+ struct kona_clk *bcm_clk = to_kona_clk(hw);
+ struct bcm_clk_div *div = &bcm_clk->u.peri->div;
+
+ if (!divider_exists(div))
+ return clk_hw_get_rate(hw);
+
+ /* Quietly avoid a zero rate */
+ return round_rate(bcm_clk->ccu, div, &bcm_clk->u.peri->pre_div,
+ rate ? rate : 1, *parent_rate, NULL);
+}
+
+static int kona_peri_clk_determine_rate(struct clk_hw *hw,
+ struct clk_rate_request *req)
+{
+ struct kona_clk *bcm_clk = to_kona_clk(hw);
+ struct clk_hw *current_parent;
+ unsigned long parent_rate;
+ unsigned long best_delta;
+ unsigned long best_rate;
+ u32 parent_count;
+ long rate;
+ u32 which;
+
+ /*
+ * If there is no other parent to choose, use the current one.
+ * Note: We don't honor (or use) CLK_SET_RATE_NO_REPARENT.
+ */
+ WARN_ON_ONCE(bcm_clk->init_data.flags & CLK_SET_RATE_NO_REPARENT);
+ parent_count = (u32)bcm_clk->init_data.num_parents;
+ if (parent_count < 2) {
+ rate = kona_peri_clk_round_rate(hw, req->rate,
+ &req->best_parent_rate);
+ if (rate < 0)
+ return rate;
+
+ req->rate = rate;
+ return 0;
+ }
+
+ /* Unless we can do better, stick with current parent */
+ current_parent = clk_hw_get_parent(hw);
+ parent_rate = clk_hw_get_rate(current_parent);
+ best_rate = kona_peri_clk_round_rate(hw, req->rate, &parent_rate);
+ best_delta = abs(best_rate - req->rate);
+
+ /* Check whether any other parent clock can produce a better result */
+ for (which = 0; which < parent_count; which++) {
+ struct clk_hw *parent = clk_hw_get_parent_by_index(hw, which);
+ unsigned long delta;
+ unsigned long other_rate;
+
+ BUG_ON(!parent);
+ if (parent == current_parent)
+ continue;
+
+ /* We don't support CLK_SET_RATE_PARENT */
+ parent_rate = clk_hw_get_rate(parent);
+ other_rate = kona_peri_clk_round_rate(hw, req->rate,
+ &parent_rate);
+ delta = abs(other_rate - req->rate);
+ if (delta < best_delta) {
+ best_delta = delta;
+ best_rate = other_rate;
+ req->best_parent_hw = parent;
+ req->best_parent_rate = parent_rate;
+ }
+ }
+
+ req->rate = best_rate;
+ return 0;
+}
+
+static int kona_peri_clk_set_parent(struct clk_hw *hw, u8 index)
+{
+ struct kona_clk *bcm_clk = to_kona_clk(hw);
+ struct peri_clk_data *data = bcm_clk->u.peri;
+ struct bcm_clk_sel *sel = &data->sel;
+ struct bcm_clk_trig *trig;
+ int ret;
+
+ BUG_ON(index >= sel->parent_count);
+
+ /* If there's only one parent we don't require a selector */
+ if (!selector_exists(sel))
+ return 0;
+
+ /*
+ * The regular trigger is used by default, but if there's a
+ * pre-trigger we want to use that instead.
+ */
+ trig = trigger_exists(&data->pre_trig) ? &data->pre_trig
+ : &data->trig;
+
+ ret = selector_write(bcm_clk->ccu, &data->gate, sel, trig, index);
+ if (ret == -ENXIO) {
+ pr_err("%s: gating failure for %s\n", __func__,
+ bcm_clk->init_data.name);
+ ret = -EIO; /* Don't proliferate weird errors */
+ } else if (ret == -EIO) {
+ pr_err("%s: %strigger failed for %s\n", __func__,
+ trig == &data->pre_trig ? "pre-" : "",
+ bcm_clk->init_data.name);
+ }
+
+ return ret;
+}
+
+static u8 kona_peri_clk_get_parent(struct clk_hw *hw)
+{
+ struct kona_clk *bcm_clk = to_kona_clk(hw);
+ struct peri_clk_data *data = bcm_clk->u.peri;
+ u8 index;
+
+ index = selector_read_index(bcm_clk->ccu, &data->sel);
+
+ /* Not all callers would handle an out-of-range value gracefully */
+ return index == BAD_CLK_INDEX ? 0 : index;
+}
+
+static int kona_peri_clk_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ struct kona_clk *bcm_clk = to_kona_clk(hw);
+ struct peri_clk_data *data = bcm_clk->u.peri;
+ struct bcm_clk_div *div = &data->div;
+ u64 scaled_div = 0;
+ int ret;
+
+ if (parent_rate > (unsigned long)LONG_MAX)
+ return -EINVAL;
+
+ if (rate == clk_hw_get_rate(hw))
+ return 0;
+
+ if (!divider_exists(div))
+ return rate == parent_rate ? 0 : -EINVAL;
+
+ /*
+ * A fixed divider can't be changed. (Nor can a fixed
+ * pre-divider be, but for now we never actually try to
+ * change that.) Tolerate a request for a no-op change.
+ */
+ if (divider_is_fixed(&data->div))
+ return rate == parent_rate ? 0 : -EINVAL;
+
+ /*
+ * Get the scaled divisor value needed to achieve a clock
+ * rate as close as possible to what was requested, given
+ * the parent clock rate supplied.
+ */
+ (void)round_rate(bcm_clk->ccu, div, &data->pre_div,
+ rate ? rate : 1, parent_rate, &scaled_div);
+
+ /*
+ * We aren't updating any pre-divider at this point, so
+ * we'll use the regular trigger.
+ */
+ ret = divider_write(bcm_clk->ccu, &data->gate, &data->div,
+ &data->trig, scaled_div);
+ if (ret == -ENXIO) {
+ pr_err("%s: gating failure for %s\n", __func__,
+ bcm_clk->init_data.name);
+ ret = -EIO; /* Don't proliferate weird errors */
+ } else if (ret == -EIO) {
+ pr_err("%s: trigger failed for %s\n", __func__,
+ bcm_clk->init_data.name);
+ }
+
+ return ret;
+}
+
+struct clk_ops kona_peri_clk_ops = {
+ .enable = kona_peri_clk_enable,
+ .disable = kona_peri_clk_disable,
+ .is_enabled = kona_peri_clk_is_enabled,
+ .recalc_rate = kona_peri_clk_recalc_rate,
+ .determine_rate = kona_peri_clk_determine_rate,
+ .set_parent = kona_peri_clk_set_parent,
+ .get_parent = kona_peri_clk_get_parent,
+ .set_rate = kona_peri_clk_set_rate,
+};
+
+/* Put a peripheral clock into its initial state */
+static bool __peri_clk_init(struct kona_clk *bcm_clk)
+{
+ struct ccu_data *ccu = bcm_clk->ccu;
+ struct peri_clk_data *peri = bcm_clk->u.peri;
+ const char *name = bcm_clk->init_data.name;
+ struct bcm_clk_trig *trig;
+
+ BUG_ON(bcm_clk->type != bcm_clk_peri);
+
+ if (!policy_init(ccu, &peri->policy)) {
+ pr_err("%s: error initializing policy for %s\n",
+ __func__, name);
+ return false;
+ }
+ if (!gate_init(ccu, &peri->gate)) {
+ pr_err("%s: error initializing gate for %s\n", __func__, name);
+ return false;
+ }
+ if (!hyst_init(ccu, &peri->hyst)) {
+ pr_err("%s: error initializing hyst for %s\n", __func__, name);
+ return false;
+ }
+ if (!div_init(ccu, &peri->gate, &peri->div, &peri->trig)) {
+ pr_err("%s: error initializing divider for %s\n", __func__,
+ name);
+ return false;
+ }
+
+ /*
+ * For the pre-divider and selector, the pre-trigger is used
+ * if it's present, otherwise we just use the regular trigger.
+ */
+ trig = trigger_exists(&peri->pre_trig) ? &peri->pre_trig
+ : &peri->trig;
+
+ if (!div_init(ccu, &peri->gate, &peri->pre_div, trig)) {
+ pr_err("%s: error initializing pre-divider for %s\n", __func__,
+ name);
+ return false;
+ }
+
+ if (!sel_init(ccu, &peri->gate, &peri->sel, trig)) {
+ pr_err("%s: error initializing selector for %s\n", __func__,
+ name);
+ return false;
+ }
+
+ return true;
+}
+
+static bool __kona_clk_init(struct kona_clk *bcm_clk)
+{
+ switch (bcm_clk->type) {
+ case bcm_clk_peri:
+ return __peri_clk_init(bcm_clk);
+ default:
+ BUG();
+ }
+ return false;
+}
+
+/* Set a CCU and all its clocks into their desired initial state */
+bool __init kona_ccu_init(struct ccu_data *ccu)
+{
+ unsigned long flags;
+ unsigned int which;
+ struct kona_clk *kona_clks = ccu->kona_clks;
+ bool success = true;
+
+ flags = ccu_lock(ccu);
+ __ccu_write_enable(ccu);
+
+ for (which = 0; which < ccu->clk_num; which++) {
+ struct kona_clk *bcm_clk = &kona_clks[which];
+
+ if (!bcm_clk->ccu)
+ continue;
+
+ success &= __kona_clk_init(bcm_clk);
+ }
+
+ __ccu_write_disable(ccu);
+ ccu_unlock(ccu, flags);
+ return success;
+}