/*
* PLL clock driver for Keystone devices
*
* Copyright (C) 2013 Texas Instruments Inc.
* Murali Karicheri <m-karicheri2@ti.com>
* Santosh Shilimkar <santosh.shilimkar@ti.com>
*
* 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; either version 2 of the License, or
* (at your option) any later version.
*/
#include <linux/clk-provider.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/of_address.h>
#include <linux/of.h>
#include <linux/module.h>
#define PLLM_LOW_MASK 0x3f
#define PLLM_HIGH_MASK 0x7ffc0
#define MAIN_PLLM_HIGH_MASK 0x7f000
#define PLLM_HIGH_SHIFT 6
#define PLLD_MASK 0x3f
#define CLKOD_MASK 0x780000
#define CLKOD_SHIFT 19
/**
* struct clk_pll_data - pll data structure
* @has_pllctrl: If set to non zero, lower 6 bits of multiplier is in pllm
* register of pll controller, else it is in the pll_ctrl0((bit 11-6)
* @phy_pllm: Physical address of PLLM in pll controller. Used when
* has_pllctrl is non zero.
* @phy_pll_ctl0: Physical address of PLL ctrl0. This could be that of
* Main PLL or any other PLLs in the device such as ARM PLL, DDR PLL
* or PA PLL available on keystone2. These PLLs are controlled by
* this register. Main PLL is controlled by a PLL controller.
* @pllm: PLL register map address for multiplier bits
* @pllod: PLL register map address for post divider bits
* @pll_ctl0: PLL controller map address
* @pllm_lower_mask: multiplier lower mask
* @pllm_upper_mask: multiplier upper mask
* @pllm_upper_shift: multiplier upper shift
* @plld_mask: divider mask
* @clkod_mask: output divider mask
* @clkod_shift: output divider shift
* @plld_mask: divider mask
* @postdiv: Fixed post divider
*/
struct clk_pll_data {
bool has_pllctrl;
u32 phy_pllm;
u32 phy_pll_ctl0;
void __iomem *pllm;
void __iomem *pllod;
void __iomem *pll_ctl0;
u32 pllm_lower_mask;
u32 pllm_upper_mask;
u32 pllm_upper_shift;
u32 plld_mask;
u32 clkod_mask;
u32 clkod_shift;
u32 postdiv;
};
/**
* struct clk_pll - Main pll clock
* @hw: clk_hw for the pll
* @pll_data: PLL driver specific data
*/
struct clk_pll {
struct clk_hw hw;
struct clk_pll_data *pll_data;
};
#define to_clk_pll(_hw) container_of(_hw, struct clk_pll, hw)
static unsigned long clk_pllclk_recalc(struct clk_hw *hw,
unsigned long parent_rate)
{
struct clk_pll *pll = to_clk_pll(hw);
struct clk_pll_data *pll_data = pll->pll_data;
unsigned long rate = parent_rate;
u32 mult = 0, prediv, postdiv, val;
/*
* get bits 0-5 of multiplier from pllctrl PLLM register
* if has_pllctrl is non zero
*/
if (pll_data->has_pllctrl) {
val = readl(pll_data->pllm);
mult = (val & pll_data->pllm_lower_mask);
}
/* bit6-12 of PLLM is in Main PLL control register */
val = readl(pll_data->pll_ctl0);
mult |= ((val & pll_data->pllm_upper_mask)
>> pll_data->pllm_upper_shift);
prediv = (val & pll_data->plld_mask);
if (!pll_data->has_pllctrl)
/* read post divider from od bits*/
postdiv = ((val & pll_data->clkod_mask) >>
pll_data->clkod_shift) + 1;
else if (pll_data->pllod) {
postdiv = readl(pll_data->pllod);
postdiv = ((postdiv & pll_data->clkod_mask) >>
pll_data->clkod_shift) + 1;
} else
postdiv = pll_data->postdiv;
rate /= (prediv + 1);
rate = (rate * (mult + 1));
rate /= postdiv;
return rate;
}
static const struct clk_ops clk_pll_ops = {
.recalc_rate = clk_pllclk_recalc,
};
static struct clk *clk_register_pll(struct device *dev,
const char *name,
const char *parent_name,
struct clk_pll_data *pll_data)
{
struct clk_init_data init;
struct clk_pll *pll;
struct clk *clk;
pll = kzalloc(sizeof(*pll), GFP_KERNEL);
if (!pll)
return ERR_PTR(-ENOMEM);
init.name = name;
init.ops = &clk_pll_ops;
init.flags = 0;
init.parent_names = (parent_name ? &parent_name : NULL);
init.num_parents = (parent_name ? 1 : 0);
pll->pll_data = pll_data;
pll->hw.init = &init;
clk = clk_register(NULL, &pll->hw);
if (IS_ERR(clk))
goto out;
return clk;
out:
kfree(pll);
return NULL;
}
/**
* _of_clk_init - PLL initialisation via DT
* @node: device tree node for this clock
* @pllctrl: If true, lower 6 bits of multiplier is in pllm register of
* pll controller, else it is in the control register0(bit 11-6)
*/
static void __init _of_pll_clk_init(struct device_node *node, bool pllctrl)
{
struct clk_pll_data *pll_data;
const char *parent_name;
struct clk *clk;
int i;
pll_data = kzalloc(sizeof(*pll_data), GFP_KERNEL);
if (!pll_data) {
pr_err("%s: Out of memory\n", __func__);
return;
}
parent_name = of_clk_get_parent_name(node, 0);
if (of_property_read_u32(node, "fixed-postdiv", &pll_data->postdiv)) {
/* assume the PLL has output divider register bits */
pll_data->clkod_mask = CLKOD_MASK;
pll_data->clkod_shift = CLKOD_SHIFT;
/*
* Check if there is an post-divider register. If not
* assume od bits are part of control register.
*/
i = of_property_match_string(node, "reg-names",
"post-divider");
pll_data->pllod = of_iomap(node, i);
}
i = of_property_match_string(node, "reg-names", "control");
pll_data->pll_ctl0 = of_iomap(node, i);
if (!pll_data->pll_ctl0) {
pr_err("%s: ioremap failed\n", __func__);
iounmap(pll_data->pllod);
goto out;
}
pll_data->pllm_lower_mask = PLLM_LOW_MASK;
pll_data->pllm_upper_shift = PLLM_HIGH_SHIFT;
pll_data->plld_mask = PLLD_MASK;
pll_data->has_pllctrl = pllctrl;
if (!pll_data->has_pllctrl) {
pll_data->pllm_upper_mask = PLLM_HIGH_MASK;
} else {
pll_data->pllm_upper_mask = MAIN_PLLM_HIGH_MASK;
i = of_property_match_string(node, "reg-names", "multiplier");
pll_data->pllm = of_iomap(node, i);
if (!pll_data->pllm) {
iounmap(pll_data->pll_ctl0);
iounmap(pll_data->pllod);
goto out;
}
}
clk = clk_register_pll(NULL, node->name, parent_name, pll_data);
if (clk) {
of_clk_add_provider(node, of_clk_src_simple_get, clk);
return;
}
out:
pr_err("%s: error initializing pll %s\n", __func__, node->name);
kfree(pll_data);
}
/**
* of_keystone_pll_clk_init - PLL initialisation DT wrapper
* @node: device tree node for this clock
*/
static void __init of_keystone_pll_clk_init(struct device_node *node)
{
_of_pll_clk_init(node, false);
}
CLK_OF_DECLARE(keystone_pll_clock, "ti,keystone,pll-clock",
of_keystone_pll_clk_init);
/**
* of_keystone_pll_main_clk_init - Main PLL initialisation DT wrapper
* @node: device tree node for this clock
*/
static void __init of_keystone_main_pll_clk_init(struct device_node *node)
{
_of_pll_clk_init(node, true);
}
CLK_OF_DECLARE(keystone_main_pll_clock, "ti,keystone,main-pll-clock",
of_keystone_main_pll_clk_init);
/**
* of_pll_div_clk_init - PLL divider setup function
* @node: device tree node for this clock
*/
static void __init of_pll_div_clk_init(struct device_node *node)
{
const char *parent_name;
void __iomem *reg;
u32 shift, mask;
struct clk *clk;
const char *clk_name = node->name;
of_property_read_string(node, "clock-output-names", &clk_name);
reg = of_iomap(node, 0);
if (!reg) {
pr_err("%s: ioremap failed\n", __func__);
return;
}
parent_name = of_clk_get_parent_name(node, 0);
if (!parent_name) {
pr_err("%s: missing parent clock\n", __func__);
return;
}
if (of_property_read_u32(node, "bit-shift", &shift)) {
pr_err("%s: missing 'shift' property\n", __func__);
return;
}
if (of_property_read_u32(node, "bit-mask", &mask)) {
pr_err("%s: missing 'bit-mask' property\n", __func__);
return;
}
clk = clk_register_divider(NULL, clk_name, parent_name, 0, reg, shift,
mask, 0, NULL);
if (clk)
of_clk_add_provider(node, of_clk_src_simple_get, clk);
else
pr_err("%s: error registering divider %s\n", __func__, clk_name);
}
CLK_OF_DECLARE(pll_divider_clock, "ti,keystone,pll-divider-clock", of_pll_div_clk_init);
/**
* of_pll_mux_clk_init - PLL mux setup function
* @node: device tree node for this clock
*/
static void __init of_pll_mux_clk_init(struct device_node *node)
{
void __iomem *reg;
u32 shift, mask;
struct clk *clk;
const char *parents[2];
const char *clk_name = node->name;
of_property_read_string(node, "clock-output-names", &clk_name);
reg = of_iomap(node, 0);
if (!reg) {
pr_err("%s: ioremap failed\n", __func__);
return;
}
of_clk_parent_fill(node, parents, 2);
if (!parents[0] || !parents[1]) {
pr_err("%s: missing parent clocks\n", __func__);
return;
}
if (of_property_read_u32(node, "bit-shift", &shift)) {
pr_err("%s: missing 'shift' property\n", __func__);
return;
}
if (of_property_read_u32(node, "bit-mask", &mask)) {
pr_err("%s: missing 'bit-mask' property\n", __func__);
return;
}
clk = clk_register_mux(NULL, clk_name, (const char **)&parents,
ARRAY_SIZE(parents) , 0, reg, shift, mask,
0, NULL);
if (clk)
of_clk_add_provider(node, of_clk_src_simple_get, clk);
else
pr_err("%s: error registering mux %s\n", __func__, clk_name);
}
CLK_OF_DECLARE(pll_mux_clock, "ti,keystone,pll-mux-clock", of_pll_mux_clk_init);