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-rw-r--r--arch/arm/mach-omap2/clkt_clksel.c466
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diff --git a/arch/arm/mach-omap2/clkt_clksel.c b/arch/arm/mach-omap2/clkt_clksel.c
deleted file mode 100644
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--- a/arch/arm/mach-omap2/clkt_clksel.c
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@@ -1,466 +0,0 @@
-/*
- * clkt_clksel.c - OMAP2/3/4 clksel clock functions
- *
- * Copyright (C) 2005-2008 Texas Instruments, Inc.
- * Copyright (C) 2004-2010 Nokia Corporation
- *
- * Contacts:
- * Richard Woodruff <r-woodruff2@ti.com>
- * Paul Walmsley
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- *
- * clksel clocks are clocks that do not have a fixed parent, or that
- * can divide their parent's rate, or possibly both at the same time, based
- * on the contents of a hardware register bitfield.
- *
- * All of the various mux and divider settings can be encoded into
- * struct clksel* data structures, and then these can be autogenerated
- * from some hardware database for each new chip generation. This
- * should avoid the need to write, review, and validate a lot of new
- * clock code for each new chip, since it can be exported from the SoC
- * design flow. This is now done on OMAP4.
- *
- * The fusion of mux and divider clocks is a software creation. In
- * hardware reality, the multiplexer (parent selection) and the
- * divider exist separately. XXX At some point these clksel clocks
- * should be split into "divider" clocks and "mux" clocks to better
- * match the hardware.
- *
- * (The name "clksel" comes from the name of the corresponding
- * register field in the OMAP2/3 family of SoCs.)
- *
- * XXX Currently these clocks are only used in the OMAP2/3/4 code, but
- * many of the OMAP1 clocks should be convertible to use this
- * mechanism.
- */
-#undef DEBUG
-
-#include <linux/kernel.h>
-#include <linux/errno.h>
-#include <linux/clk-provider.h>
-#include <linux/io.h>
-#include <linux/bug.h>
-
-#include "clock.h"
-
-/* Private functions */
-
-/**
- * _get_clksel_by_parent() - return clksel struct for a given clk & parent
- * @clk: OMAP struct clk ptr to inspect
- * @src_clk: OMAP struct clk ptr of the parent clk to search for
- *
- * Scan the struct clksel array associated with the clock to find
- * the element associated with the supplied parent clock address.
- * Returns a pointer to the struct clksel on success or NULL on error.
- */
-static const struct clksel *_get_clksel_by_parent(struct clk_hw_omap *clk,
- struct clk *src_clk)
-{
- const struct clksel *clks;
-
- if (!src_clk)
- return NULL;
-
- for (clks = clk->clksel; clks->parent; clks++)
- if (clks->parent == src_clk)
- break; /* Found the requested parent */
-
- if (!clks->parent) {
- /* This indicates a data problem */
- WARN(1, "clock: %s: could not find parent clock %s in clksel array\n",
- __clk_get_name(clk->hw.clk), __clk_get_name(src_clk));
- return NULL;
- }
-
- return clks;
-}
-
-/**
- * _write_clksel_reg() - program a clock's clksel register in hardware
- * @clk: struct clk * to program
- * @v: clksel bitfield value to program (with LSB at bit 0)
- *
- * Shift the clksel register bitfield value @v to its appropriate
- * location in the clksel register and write it in. This function
- * will ensure that the write to the clksel_reg reaches its
- * destination before returning -- important since PRM and CM register
- * accesses can be quite slow compared to ARM cycles -- but does not
- * take into account any time the hardware might take to switch the
- * clock source.
- */
-static void _write_clksel_reg(struct clk_hw_omap *clk, u32 field_val)
-{
- u32 v;
-
- v = omap2_clk_readl(clk, clk->clksel_reg);
- v &= ~clk->clksel_mask;
- v |= field_val << __ffs(clk->clksel_mask);
- omap2_clk_writel(v, clk, clk->clksel_reg);
-
- v = omap2_clk_readl(clk, clk->clksel_reg); /* OCP barrier */
-}
-
-/**
- * _clksel_to_divisor() - turn clksel field value into integer divider
- * @clk: OMAP struct clk to use
- * @field_val: register field value to find
- *
- * Given a struct clk of a rate-selectable clksel clock, and a register field
- * value to search for, find the corresponding clock divisor. The register
- * field value should be pre-masked and shifted down so the LSB is at bit 0
- * before calling. Returns 0 on error or returns the actual integer divisor
- * upon success.
- */
-static u32 _clksel_to_divisor(struct clk_hw_omap *clk, u32 field_val)
-{
- const struct clksel *clks;
- const struct clksel_rate *clkr;
- struct clk *parent;
-
- parent = __clk_get_parent(clk->hw.clk);
-
- clks = _get_clksel_by_parent(clk, parent);
- if (!clks)
- return 0;
-
- for (clkr = clks->rates; clkr->div; clkr++) {
- if (!(clkr->flags & cpu_mask))
- continue;
-
- if (clkr->val == field_val)
- break;
- }
-
- if (!clkr->div) {
- /* This indicates a data error */
- WARN(1, "clock: %s: could not find fieldval %d for parent %s\n",
- __clk_get_name(clk->hw.clk), field_val,
- __clk_get_name(parent));
- return 0;
- }
-
- return clkr->div;
-}
-
-/**
- * _divisor_to_clksel() - turn clksel integer divisor into a field value
- * @clk: OMAP struct clk to use
- * @div: integer divisor to search for
- *
- * Given a struct clk of a rate-selectable clksel clock, and a clock
- * divisor, find the corresponding register field value. Returns the
- * register field value _before_ left-shifting (i.e., LSB is at bit
- * 0); or returns 0xFFFFFFFF (~0) upon error.
- */
-static u32 _divisor_to_clksel(struct clk_hw_omap *clk, u32 div)
-{
- const struct clksel *clks;
- const struct clksel_rate *clkr;
- struct clk *parent;
-
- /* should never happen */
- WARN_ON(div == 0);
-
- parent = __clk_get_parent(clk->hw.clk);
- clks = _get_clksel_by_parent(clk, parent);
- if (!clks)
- return ~0;
-
- for (clkr = clks->rates; clkr->div; clkr++) {
- if (!(clkr->flags & cpu_mask))
- continue;
-
- if (clkr->div == div)
- break;
- }
-
- if (!clkr->div) {
- pr_err("clock: %s: could not find divisor %d for parent %s\n",
- __clk_get_name(clk->hw.clk), div,
- __clk_get_name(parent));
- return ~0;
- }
-
- return clkr->val;
-}
-
-/**
- * _read_divisor() - get current divisor applied to parent clock (from hdwr)
- * @clk: OMAP struct clk to use.
- *
- * Read the current divisor register value for @clk that is programmed
- * into the hardware, convert it into the actual divisor value, and
- * return it; or return 0 on error.
- */
-static u32 _read_divisor(struct clk_hw_omap *clk)
-{
- u32 v;
-
- if (!clk->clksel || !clk->clksel_mask)
- return 0;
-
- v = omap2_clk_readl(clk, clk->clksel_reg);
- v &= clk->clksel_mask;
- v >>= __ffs(clk->clksel_mask);
-
- return _clksel_to_divisor(clk, v);
-}
-
-/* Public functions */
-
-/**
- * omap2_clksel_round_rate_div() - find divisor for the given clock and rate
- * @clk: OMAP struct clk to use
- * @target_rate: desired clock rate
- * @new_div: ptr to where we should store the divisor
- *
- * Finds 'best' divider value in an array based on the source and target
- * rates. The divider array must be sorted with smallest divider first.
- * This function is also used by the DPLL3 M2 divider code.
- *
- * Returns the rounded clock rate or returns 0xffffffff on error.
- */
-u32 omap2_clksel_round_rate_div(struct clk_hw_omap *clk,
- unsigned long target_rate,
- u32 *new_div)
-{
- unsigned long test_rate;
- const struct clksel *clks;
- const struct clksel_rate *clkr;
- u32 last_div = 0;
- struct clk *parent;
- unsigned long parent_rate;
- const char *clk_name;
-
- parent = __clk_get_parent(clk->hw.clk);
- clk_name = __clk_get_name(clk->hw.clk);
- parent_rate = __clk_get_rate(parent);
-
- if (!clk->clksel || !clk->clksel_mask)
- return ~0;
-
- pr_debug("clock: clksel_round_rate_div: %s target_rate %ld\n",
- clk_name, target_rate);
-
- *new_div = 1;
-
- clks = _get_clksel_by_parent(clk, parent);
- if (!clks)
- return ~0;
-
- for (clkr = clks->rates; clkr->div; clkr++) {
- if (!(clkr->flags & cpu_mask))
- continue;
-
- /* Sanity check */
- if (clkr->div <= last_div)
- pr_err("clock: %s: clksel_rate table not sorted\n",
- clk_name);
-
- last_div = clkr->div;
-
- test_rate = parent_rate / clkr->div;
-
- if (test_rate <= target_rate)
- break; /* found it */
- }
-
- if (!clkr->div) {
- pr_err("clock: %s: could not find divisor for target rate %ld for parent %s\n",
- clk_name, target_rate, __clk_get_name(parent));
- return ~0;
- }
-
- *new_div = clkr->div;
-
- pr_debug("clock: new_div = %d, new_rate = %ld\n", *new_div,
- (parent_rate / clkr->div));
-
- return parent_rate / clkr->div;
-}
-
-/*
- * Clocktype interface functions to the OMAP clock code
- * (i.e., those used in struct clk field function pointers, etc.)
- */
-
-/**
- * omap2_clksel_find_parent_index() - return the array index of the current
- * hardware parent of @hw
- * @hw: struct clk_hw * to find the current hardware parent of
- *
- * Given a struct clk_hw pointer @hw to the 'hw' member of a struct
- * clk_hw_omap record representing a source-selectable hardware clock,
- * read the hardware register and determine what its parent is
- * currently set to. Intended to be called only by the common clock
- * framework struct clk_hw_ops.get_parent function pointer. Return
- * the array index of this parent clock upon success -- there is no
- * way to return an error, so if we encounter an error, just WARN()
- * and pretend that we know that we're doing.
- */
-u8 omap2_clksel_find_parent_index(struct clk_hw *hw)
-{
- struct clk_hw_omap *clk = to_clk_hw_omap(hw);
- const struct clksel *clks;
- const struct clksel_rate *clkr;
- u32 r, found = 0;
- struct clk *parent;
- const char *clk_name;
- int ret = 0, f = 0;
-
- parent = __clk_get_parent(hw->clk);
- clk_name = __clk_get_name(hw->clk);
-
- /* XXX should be able to return an error */
- WARN((!clk->clksel || !clk->clksel_mask),
- "clock: %s: attempt to call on a non-clksel clock", clk_name);
-
- r = omap2_clk_readl(clk, clk->clksel_reg) & clk->clksel_mask;
- r >>= __ffs(clk->clksel_mask);
-
- for (clks = clk->clksel; clks->parent && !found; clks++) {
- for (clkr = clks->rates; clkr->div && !found; clkr++) {
- if (!(clkr->flags & cpu_mask))
- continue;
-
- if (clkr->val == r) {
- found = 1;
- ret = f;
- }
- }
- f++;
- }
-
- /* This indicates a data error */
- WARN(!found, "clock: %s: init parent: could not find regval %0x\n",
- clk_name, r);
-
- return ret;
-}
-
-
-/**
- * omap2_clksel_recalc() - function ptr to pass via struct clk .recalc field
- * @clk: struct clk *
- *
- * This function is intended to be called only by the clock framework.
- * Each clksel clock should have its struct clk .recalc field set to this
- * function. Returns the clock's current rate, based on its parent's rate
- * and its current divisor setting in the hardware.
- */
-unsigned long omap2_clksel_recalc(struct clk_hw *hw, unsigned long parent_rate)
-{
- unsigned long rate;
- u32 div = 0;
- struct clk_hw_omap *clk = to_clk_hw_omap(hw);
-
- if (!parent_rate)
- return 0;
-
- div = _read_divisor(clk);
- if (!div)
- rate = parent_rate;
- else
- rate = parent_rate / div;
-
- pr_debug("%s: recalc'd %s's rate to %lu (div %d)\n", __func__,
- __clk_get_name(hw->clk), rate, div);
-
- return rate;
-}
-
-/**
- * omap2_clksel_round_rate() - find rounded rate for the given clock and rate
- * @clk: OMAP struct clk to use
- * @target_rate: desired clock rate
- *
- * This function is intended to be called only by the clock framework.
- * Finds best target rate based on the source clock and possible dividers.
- * rates. The divider array must be sorted with smallest divider first.
- *
- * Returns the rounded clock rate or returns 0xffffffff on error.
- */
-long omap2_clksel_round_rate(struct clk_hw *hw, unsigned long target_rate,
- unsigned long *parent_rate)
-{
- struct clk_hw_omap *clk = to_clk_hw_omap(hw);
- u32 new_div;
-
- return omap2_clksel_round_rate_div(clk, target_rate, &new_div);
-}
-
-/**
- * omap2_clksel_set_rate() - program clock rate in hardware
- * @clk: struct clk * to program rate
- * @rate: target rate to program
- *
- * This function is intended to be called only by the clock framework.
- * Program @clk's rate to @rate in the hardware. The clock can be
- * either enabled or disabled when this happens, although if the clock
- * is enabled, some downstream devices may glitch or behave
- * unpredictably when the clock rate is changed - this depends on the
- * hardware. This function does not currently check the usecount of
- * the clock, so if multiple drivers are using the clock, and the rate
- * is changed, they will all be affected without any notification.
- * Returns -EINVAL upon error, or 0 upon success.
- */
-int omap2_clksel_set_rate(struct clk_hw *hw, unsigned long rate,
- unsigned long parent_rate)
-{
- struct clk_hw_omap *clk = to_clk_hw_omap(hw);
- u32 field_val, validrate, new_div = 0;
-
- if (!clk->clksel || !clk->clksel_mask)
- return -EINVAL;
-
- validrate = omap2_clksel_round_rate_div(clk, rate, &new_div);
- if (validrate != rate)
- return -EINVAL;
-
- field_val = _divisor_to_clksel(clk, new_div);
- if (field_val == ~0)
- return -EINVAL;
-
- _write_clksel_reg(clk, field_val);
-
- pr_debug("clock: %s: set rate to %ld\n", __clk_get_name(hw->clk),
- __clk_get_rate(hw->clk));
-
- return 0;
-}
-
-/*
- * Clksel parent setting function - not passed in struct clk function
- * pointer - instead, the OMAP clock code currently assumes that any
- * parent-setting clock is a clksel clock, and calls
- * omap2_clksel_set_parent() by default
- */
-
-/**
- * omap2_clksel_set_parent() - change a clock's parent clock
- * @clk: struct clk * of the child clock
- * @new_parent: struct clk * of the new parent clock
- *
- * This function is intended to be called only by the clock framework.
- * Change the parent clock of clock @clk to @new_parent. This is
- * intended to be used while @clk is disabled. This function does not
- * currently check the usecount of the clock, so if multiple drivers
- * are using the clock, and the parent is changed, they will all be
- * affected without any notification. Returns -EINVAL upon error, or
- * 0 upon success.
- */
-int omap2_clksel_set_parent(struct clk_hw *hw, u8 field_val)
-{
- struct clk_hw_omap *clk = to_clk_hw_omap(hw);
-
- if (!clk->clksel || !clk->clksel_mask)
- return -EINVAL;
-
- _write_clksel_reg(clk, field_val);
- return 0;
-}