--- /dev/null
+/*
+ * 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.
+ */
+
+#ifndef _CLK_KONA_H
+#define _CLK_KONA_H
+
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/spinlock.h>
+#include <linux/slab.h>
+#include <linux/device.h>
+#include <linux/of.h>
+#include <linux/clk-provider.h>
+
+#define BILLION 1000000000
+
+/* The common clock framework uses u8 to represent a parent index */
+#define PARENT_COUNT_MAX ((u32)U8_MAX)
+
+#define BAD_CLK_INDEX U8_MAX /* Can't ever be valid */
+#define BAD_CLK_NAME ((const char *)-1)
+
+#define BAD_SCALED_DIV_VALUE U64_MAX
+
+/*
+ * Utility macros for object flag management. If possible, flags
+ * should be defined such that 0 is the desired default value.
+ */
+#define FLAG(type, flag) BCM_CLK_ ## type ## _FLAGS_ ## flag
+#define FLAG_SET(obj, type, flag) ((obj)->flags |= FLAG(type, flag))
+#define FLAG_CLEAR(obj, type, flag) ((obj)->flags &= ~(FLAG(type, flag)))
+#define FLAG_FLIP(obj, type, flag) ((obj)->flags ^= FLAG(type, flag))
+#define FLAG_TEST(obj, type, flag) (!!((obj)->flags & FLAG(type, flag)))
+
+/* CCU field state tests */
+
+#define ccu_policy_exists(ccu_policy) ((ccu_policy)->enable.offset != 0)
+
+/* Clock field state tests */
+
+#define policy_exists(policy) ((policy)->offset != 0)
+
+#define gate_exists(gate) FLAG_TEST(gate, GATE, EXISTS)
+#define gate_is_enabled(gate) FLAG_TEST(gate, GATE, ENABLED)
+#define gate_is_hw_controllable(gate) FLAG_TEST(gate, GATE, HW)
+#define gate_is_sw_controllable(gate) FLAG_TEST(gate, GATE, SW)
+#define gate_is_sw_managed(gate) FLAG_TEST(gate, GATE, SW_MANAGED)
+#define gate_is_no_disable(gate) FLAG_TEST(gate, GATE, NO_DISABLE)
+
+#define gate_flip_enabled(gate) FLAG_FLIP(gate, GATE, ENABLED)
+
+#define hyst_exists(hyst) ((hyst)->offset != 0)
+
+#define divider_exists(div) FLAG_TEST(div, DIV, EXISTS)
+#define divider_is_fixed(div) FLAG_TEST(div, DIV, FIXED)
+#define divider_has_fraction(div) (!divider_is_fixed(div) && \
+ (div)->u.s.frac_width > 0)
+
+#define selector_exists(sel) ((sel)->width != 0)
+#define trigger_exists(trig) FLAG_TEST(trig, TRIG, EXISTS)
+
+#define policy_lvm_en_exists(enable) ((enable)->offset != 0)
+#define policy_ctl_exists(control) ((control)->offset != 0)
+
+/* Clock type, used to tell common block what it's part of */
+enum bcm_clk_type {
+ bcm_clk_none, /* undefined clock type */
+ bcm_clk_bus,
+ bcm_clk_core,
+ bcm_clk_peri
+};
+
+/*
+ * CCU policy control for clocks. Clocks can be enabled or disabled
+ * based on the CCU policy in effect. One bit in each policy mask
+ * register (one per CCU policy) represents whether the clock is
+ * enabled when that policy is effect or not. The CCU policy engine
+ * must be stopped to update these bits, and must be restarted again
+ * afterward.
+ */
+struct bcm_clk_policy {
+ u32 offset; /* first policy mask register offset */
+ u32 bit; /* bit used in all mask registers */
+};
+
+/* Policy initialization macro */
+
+#define POLICY(_offset, _bit) \
+ { \
+ .offset = (_offset), \
+ .bit = (_bit), \
+ }
+
+/*
+ * Gating control and status is managed by a 32-bit gate register.
+ *
+ * There are several types of gating available:
+ * - (no gate)
+ * A clock with no gate is assumed to be always enabled.
+ * - hardware-only gating (auto-gating)
+ * Enabling or disabling clocks with this type of gate is
+ * managed automatically by the hardware. Such clocks can be
+ * considered by the software to be enabled. The current status
+ * of auto-gated clocks can be read from the gate status bit.
+ * - software-only gating
+ * Auto-gating is not available for this type of clock.
+ * Instead, software manages whether it's enabled by setting or
+ * clearing the enable bit. The current gate status of a gate
+ * under software control can be read from the gate status bit.
+ * To ensure a change to the gating status is complete, the
+ * status bit can be polled to verify that the gate has entered
+ * the desired state.
+ * - selectable hardware or software gating
+ * Gating for this type of clock can be configured to be either
+ * under software or hardware control. Which type is in use is
+ * determined by the hw_sw_sel bit of the gate register.
+ */
+struct bcm_clk_gate {
+ u32 offset; /* gate register offset */
+ u32 status_bit; /* 0: gate is disabled; 0: gatge is enabled */
+ u32 en_bit; /* 0: disable; 1: enable */
+ u32 hw_sw_sel_bit; /* 0: hardware gating; 1: software gating */
+ u32 flags; /* BCM_CLK_GATE_FLAGS_* below */
+};
+
+/*
+ * Gate flags:
+ * HW means this gate can be auto-gated
+ * SW means the state of this gate can be software controlled
+ * NO_DISABLE means this gate is (only) enabled if under software control
+ * SW_MANAGED means the status of this gate is under software control
+ * ENABLED means this software-managed gate is *supposed* to be enabled
+ */
+#define BCM_CLK_GATE_FLAGS_EXISTS ((u32)1 << 0) /* Gate is valid */
+#define BCM_CLK_GATE_FLAGS_HW ((u32)1 << 1) /* Can auto-gate */
+#define BCM_CLK_GATE_FLAGS_SW ((u32)1 << 2) /* Software control */
+#define BCM_CLK_GATE_FLAGS_NO_DISABLE ((u32)1 << 3) /* HW or enabled */
+#define BCM_CLK_GATE_FLAGS_SW_MANAGED ((u32)1 << 4) /* SW now in control */
+#define BCM_CLK_GATE_FLAGS_ENABLED ((u32)1 << 5) /* If SW_MANAGED */
+
+/*
+ * Gate initialization macros.
+ *
+ * Any gate initially under software control will be enabled.
+ */
+
+/* A hardware/software gate initially under software control */
+#define HW_SW_GATE(_offset, _status_bit, _en_bit, _hw_sw_sel_bit) \
+ { \
+ .offset = (_offset), \
+ .status_bit = (_status_bit), \
+ .en_bit = (_en_bit), \
+ .hw_sw_sel_bit = (_hw_sw_sel_bit), \
+ .flags = FLAG(GATE, HW)|FLAG(GATE, SW)| \
+ FLAG(GATE, SW_MANAGED)|FLAG(GATE, ENABLED)| \
+ FLAG(GATE, EXISTS), \
+ }
+
+/* A hardware/software gate initially under hardware control */
+#define HW_SW_GATE_AUTO(_offset, _status_bit, _en_bit, _hw_sw_sel_bit) \
+ { \
+ .offset = (_offset), \
+ .status_bit = (_status_bit), \
+ .en_bit = (_en_bit), \
+ .hw_sw_sel_bit = (_hw_sw_sel_bit), \
+ .flags = FLAG(GATE, HW)|FLAG(GATE, SW)| \
+ FLAG(GATE, EXISTS), \
+ }
+
+/* A hardware-or-enabled gate (enabled if not under hardware control) */
+#define HW_ENABLE_GATE(_offset, _status_bit, _en_bit, _hw_sw_sel_bit) \
+ { \
+ .offset = (_offset), \
+ .status_bit = (_status_bit), \
+ .en_bit = (_en_bit), \
+ .hw_sw_sel_bit = (_hw_sw_sel_bit), \
+ .flags = FLAG(GATE, HW)|FLAG(GATE, SW)| \
+ FLAG(GATE, NO_DISABLE)|FLAG(GATE, EXISTS), \
+ }
+
+/* A software-only gate */
+#define SW_ONLY_GATE(_offset, _status_bit, _en_bit) \
+ { \
+ .offset = (_offset), \
+ .status_bit = (_status_bit), \
+ .en_bit = (_en_bit), \
+ .flags = FLAG(GATE, SW)|FLAG(GATE, SW_MANAGED)| \
+ FLAG(GATE, ENABLED)|FLAG(GATE, EXISTS), \
+ }
+
+/* A hardware-only gate */
+#define HW_ONLY_GATE(_offset, _status_bit) \
+ { \
+ .offset = (_offset), \
+ .status_bit = (_status_bit), \
+ .flags = FLAG(GATE, HW)|FLAG(GATE, EXISTS), \
+ }
+
+/* Gate hysteresis for clocks */
+struct bcm_clk_hyst {
+ u32 offset; /* hyst register offset (normally CLKGATE) */
+ u32 en_bit; /* bit used to enable hysteresis */
+ u32 val_bit; /* if enabled: 0 = low delay; 1 = high delay */
+};
+
+/* Hysteresis initialization macro */
+
+#define HYST(_offset, _en_bit, _val_bit) \
+ { \
+ .offset = (_offset), \
+ .en_bit = (_en_bit), \
+ .val_bit = (_val_bit), \
+ }
+
+/*
+ * Each clock can have zero, one, or two dividers which change the
+ * output rate of the clock. Each divider can be either fixed or
+ * variable. If there are two dividers, they are the "pre-divider"
+ * and the "regular" or "downstream" divider. If there is only one,
+ * there is no pre-divider.
+ *
+ * A fixed divider is any non-zero (positive) value, and it
+ * indicates how the input rate is affected by the divider.
+ *
+ * The value of a variable divider is maintained in a sub-field of a
+ * 32-bit divider register. The position of the field in the
+ * register is defined by its offset and width. The value recorded
+ * in this field is always 1 less than the value it represents.
+ *
+ * In addition, a variable divider can indicate that some subset
+ * of its bits represent a "fractional" part of the divider. Such
+ * bits comprise the low-order portion of the divider field, and can
+ * be viewed as representing the portion of the divider that lies to
+ * the right of the decimal point. Most variable dividers have zero
+ * fractional bits. Variable dividers with non-zero fraction width
+ * still record a value 1 less than the value they represent; the
+ * added 1 does *not* affect the low-order bit in this case, it
+ * affects the bits above the fractional part only. (Often in this
+ * code a divider field value is distinguished from the value it
+ * represents by referring to the latter as a "divisor".)
+ *
+ * In order to avoid dealing with fractions, divider arithmetic is
+ * performed using "scaled" values. A scaled value is one that's
+ * been left-shifted by the fractional width of a divider. Dividing
+ * a scaled value by a scaled divisor produces the desired quotient
+ * without loss of precision and without any other special handling
+ * for fractions.
+ *
+ * The recorded value of a variable divider can be modified. To
+ * modify either divider (or both), a clock must be enabled (i.e.,
+ * using its gate). In addition, a trigger register (described
+ * below) must be used to commit the change, and polled to verify
+ * the change is complete.
+ */
+struct bcm_clk_div {
+ union {
+ struct { /* variable divider */
+ u32 offset; /* divider register offset */
+ u32 shift; /* field shift */
+ u32 width; /* field width */
+ u32 frac_width; /* field fraction width */
+
+ u64 scaled_div; /* scaled divider value */
+ } s;
+ u32 fixed; /* non-zero fixed divider value */
+ } u;
+ u32 flags; /* BCM_CLK_DIV_FLAGS_* below */
+};
+
+/*
+ * Divider flags:
+ * EXISTS means this divider exists
+ * FIXED means it is a fixed-rate divider
+ */
+#define BCM_CLK_DIV_FLAGS_EXISTS ((u32)1 << 0) /* Divider is valid */
+#define BCM_CLK_DIV_FLAGS_FIXED ((u32)1 << 1) /* Fixed-value */
+
+/* Divider initialization macros */
+
+/* A fixed (non-zero) divider */
+#define FIXED_DIVIDER(_value) \
+ { \
+ .u.fixed = (_value), \
+ .flags = FLAG(DIV, EXISTS)|FLAG(DIV, FIXED), \
+ }
+
+/* A divider with an integral divisor */
+#define DIVIDER(_offset, _shift, _width) \
+ { \
+ .u.s.offset = (_offset), \
+ .u.s.shift = (_shift), \
+ .u.s.width = (_width), \
+ .u.s.scaled_div = BAD_SCALED_DIV_VALUE, \
+ .flags = FLAG(DIV, EXISTS), \
+ }
+
+/* A divider whose divisor has an integer and fractional part */
+#define FRAC_DIVIDER(_offset, _shift, _width, _frac_width) \
+ { \
+ .u.s.offset = (_offset), \
+ .u.s.shift = (_shift), \
+ .u.s.width = (_width), \
+ .u.s.frac_width = (_frac_width), \
+ .u.s.scaled_div = BAD_SCALED_DIV_VALUE, \
+ .flags = FLAG(DIV, EXISTS), \
+ }
+
+/*
+ * Clocks may have multiple "parent" clocks. If there is more than
+ * one, a selector must be specified to define which of the parent
+ * clocks is currently in use. The selected clock is indicated in a
+ * sub-field of a 32-bit selector register. The range of
+ * representable selector values typically exceeds the number of
+ * available parent clocks. Occasionally the reset value of a
+ * selector field is explicitly set to a (specific) value that does
+ * not correspond to a defined input clock.
+ *
+ * We register all known parent clocks with the common clock code
+ * using a packed array (i.e., no empty slots) of (parent) clock
+ * names, and refer to them later using indexes into that array.
+ * We maintain an array of selector values indexed by common clock
+ * index values in order to map between these common clock indexes
+ * and the selector values used by the hardware.
+ *
+ * Like dividers, a selector can be modified, but to do so a clock
+ * must be enabled, and a trigger must be used to commit the change.
+ */
+struct bcm_clk_sel {
+ u32 offset; /* selector register offset */
+ u32 shift; /* field shift */
+ u32 width; /* field width */
+
+ u32 parent_count; /* number of entries in parent_sel[] */
+ u32 *parent_sel; /* array of parent selector values */
+ u8 clk_index; /* current selected index in parent_sel[] */
+};
+
+/* Selector initialization macro */
+#define SELECTOR(_offset, _shift, _width) \
+ { \
+ .offset = (_offset), \
+ .shift = (_shift), \
+ .width = (_width), \
+ .clk_index = BAD_CLK_INDEX, \
+ }
+
+/*
+ * Making changes to a variable divider or a selector for a clock
+ * requires the use of a trigger. A trigger is defined by a single
+ * bit within a register. To signal a change, a 1 is written into
+ * that bit. To determine when the change has been completed, that
+ * trigger bit is polled; the read value will be 1 while the change
+ * is in progress, and 0 when it is complete.
+ *
+ * Occasionally a clock will have more than one trigger. In this
+ * case, the "pre-trigger" will be used when changing a clock's
+ * selector and/or its pre-divider.
+ */
+struct bcm_clk_trig {
+ u32 offset; /* trigger register offset */
+ u32 bit; /* trigger bit */
+ u32 flags; /* BCM_CLK_TRIG_FLAGS_* below */
+};
+
+/*
+ * Trigger flags:
+ * EXISTS means this trigger exists
+ */
+#define BCM_CLK_TRIG_FLAGS_EXISTS ((u32)1 << 0) /* Trigger is valid */
+
+/* Trigger initialization macro */
+#define TRIGGER(_offset, _bit) \
+ { \
+ .offset = (_offset), \
+ .bit = (_bit), \
+ .flags = FLAG(TRIG, EXISTS), \
+ }
+
+struct peri_clk_data {
+ struct bcm_clk_policy policy;
+ struct bcm_clk_gate gate;
+ struct bcm_clk_hyst hyst;
+ struct bcm_clk_trig pre_trig;
+ struct bcm_clk_div pre_div;
+ struct bcm_clk_trig trig;
+ struct bcm_clk_div div;
+ struct bcm_clk_sel sel;
+ const char *clocks[]; /* must be last; use CLOCKS() to declare */
+};
+#define CLOCKS(...) { __VA_ARGS__, NULL, }
+#define NO_CLOCKS { NULL, } /* Must use of no parent clocks */
+
+struct kona_clk {
+ struct clk_hw hw;
+ struct clk_init_data init_data; /* includes name of this clock */
+ struct ccu_data *ccu; /* ccu this clock is associated with */
+ enum bcm_clk_type type;
+ union {
+ void *data;
+ struct peri_clk_data *peri;
+ } u;
+};
+#define to_kona_clk(_hw) \
+ container_of(_hw, struct kona_clk, hw)
+
+/* Initialization macro for an entry in a CCU's kona_clks[] array. */
+#define KONA_CLK(_ccu_name, _clk_name, _type) \
+ { \
+ .init_data = { \
+ .name = #_clk_name, \
+ .ops = &kona_ ## _type ## _clk_ops, \
+ }, \
+ .ccu = &_ccu_name ## _ccu_data, \
+ .type = bcm_clk_ ## _type, \
+ .u.data = &_clk_name ## _data, \
+ }
+#define LAST_KONA_CLK { .type = bcm_clk_none }
+
+/*
+ * CCU policy control. To enable software update of the policy
+ * tables the CCU policy engine must be stopped by setting the
+ * software update enable bit (LVM_EN). After an update the engine
+ * is restarted using the GO bit and either the GO_ATL or GO_AC bit.
+ */
+struct bcm_lvm_en {
+ u32 offset; /* LVM_EN register offset */
+ u32 bit; /* POLICY_CONFIG_EN bit in register */
+};
+
+/* Policy enable initialization macro */
+#define CCU_LVM_EN(_offset, _bit) \
+ { \
+ .offset = (_offset), \
+ .bit = (_bit), \
+ }
+
+struct bcm_policy_ctl {
+ u32 offset; /* POLICY_CTL register offset */
+ u32 go_bit;
+ u32 atl_bit; /* GO, GO_ATL, and GO_AC bits */
+ u32 ac_bit;
+};
+
+/* Policy control initialization macro */
+#define CCU_POLICY_CTL(_offset, _go_bit, _ac_bit, _atl_bit) \
+ { \
+ .offset = (_offset), \
+ .go_bit = (_go_bit), \
+ .ac_bit = (_ac_bit), \
+ .atl_bit = (_atl_bit), \
+ }
+
+struct ccu_policy {
+ struct bcm_lvm_en enable;
+ struct bcm_policy_ctl control;
+};
+
+/*
+ * Each CCU defines a mapped area of memory containing registers
+ * used to manage clocks implemented by the CCU. Access to memory
+ * within the CCU's space is serialized by a spinlock. Before any
+ * (other) address can be written, a special access "password" value
+ * must be written to its WR_ACCESS register (located at the base
+ * address of the range). We keep track of the name of each CCU as
+ * it is set up, and maintain them in a list.
+ */
+struct ccu_data {
+ void __iomem *base; /* base of mapped address space */
+ spinlock_t lock; /* serialization lock */
+ bool write_enabled; /* write access is currently enabled */
+ struct ccu_policy policy;
+ struct list_head links; /* for ccu_list */
+ struct device_node *node;
+ struct clk_onecell_data clk_data;
+ const char *name;
+ u32 range; /* byte range of address space */
+ struct kona_clk kona_clks[]; /* must be last */
+};
+
+/* Initialization for common fields in a Kona ccu_data structure */
+#define KONA_CCU_COMMON(_prefix, _name, _ccuname) \
+ .name = #_name "_ccu", \
+ .lock = __SPIN_LOCK_UNLOCKED(_name ## _ccu_data.lock), \
+ .links = LIST_HEAD_INIT(_name ## _ccu_data.links), \
+ .clk_data = { \
+ .clk_num = _prefix ## _ ## _ccuname ## _CCU_CLOCK_COUNT, \
+ }
+
+/* Exported globals */
+
+extern struct clk_ops kona_peri_clk_ops;
+
+/* Externally visible functions */
+
+extern u64 scaled_div_max(struct bcm_clk_div *div);
+extern u64 scaled_div_build(struct bcm_clk_div *div, u32 div_value,
+ u32 billionths);
+
+extern struct clk *kona_clk_setup(struct kona_clk *bcm_clk);
+extern void __init kona_dt_ccu_setup(struct ccu_data *ccu,
+ struct device_node *node);
+extern bool __init kona_ccu_init(struct ccu_data *ccu);
+
+#endif /* _CLK_KONA_H */
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