Commit cf8de5a7 authored by Alexandre Belloni's avatar Alexandre Belloni Committed by Mike Turquette

clk: berlin: add driver for BG2x simple PLLs

This is a clock driver for the simple PLLs found on Berlin SoCs.
With repect to PLL registers and features, BG2/BG2CD and BG2Q are
slightly different, e.g. different allowed VCO dividers and bit
shifts.
Signed-off-by: default avatarAlexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: default avatarSebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Signed-off-by: default avatarMike Turquette <mturquette@linaro.org>
parent beca8ccc
obj-y += berlin2-avpll.o
obj-y += berlin2-avpll.o berlin2-pll.o
/*
* Copyright (c) 2014 Marvell Technology Group Ltd.
*
* Alexandre Belloni <alexandre.belloni@free-electrons.com>
* Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along with
* this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <linux/clk-provider.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/slab.h>
#include <asm/div64.h>
#include "berlin2-div.h"
struct berlin2_pll_map {
const u8 vcodiv[16];
u8 mult;
u8 fbdiv_shift;
u8 rfdiv_shift;
u8 divsel_shift;
};
struct berlin2_pll {
struct clk_hw hw;
void __iomem *base;
struct berlin2_pll_map map;
};
#define to_berlin2_pll(hw) container_of(hw, struct berlin2_pll, hw)
#define SPLL_CTRL0 0x00
#define SPLL_CTRL1 0x04
#define SPLL_CTRL2 0x08
#define SPLL_CTRL3 0x0c
#define SPLL_CTRL4 0x10
#define FBDIV_MASK 0x1ff
#define RFDIV_MASK 0x1f
#define DIVSEL_MASK 0xf
/*
* The output frequency formula for the pll is:
* clkout = fbdiv / refdiv * parent / vcodiv
*/
static unsigned long
berlin2_pll_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)
{
struct berlin2_pll *pll = to_berlin2_pll(hw);
struct berlin2_pll_map *map = &pll->map;
u32 val, fbdiv, rfdiv, vcodivsel, vcodiv;
u64 rate = parent_rate;
val = readl_relaxed(pll->base + SPLL_CTRL0);
fbdiv = (val >> map->fbdiv_shift) & FBDIV_MASK;
rfdiv = (val >> map->rfdiv_shift) & RFDIV_MASK;
if (rfdiv == 0) {
pr_warn("%s has zero rfdiv\n", __clk_get_name(hw->clk));
rfdiv = 1;
}
val = readl_relaxed(pll->base + SPLL_CTRL1);
vcodivsel = (val >> map->divsel_shift) & DIVSEL_MASK;
vcodiv = map->vcodiv[vcodivsel];
if (vcodiv == 0) {
pr_warn("%s has zero vcodiv (index %d)\n",
__clk_get_name(hw->clk), vcodivsel);
vcodiv = 1;
}
rate *= fbdiv * map->mult;
do_div(rate, rfdiv * vcodiv);
return (unsigned long)rate;
}
static const struct clk_ops berlin2_pll_ops = {
.recalc_rate = berlin2_pll_recalc_rate,
};
struct clk * __init
berlin2_pll_register(const struct berlin2_pll_map *map,
void __iomem *base, const char *name,
const char *parent_name, unsigned long flags)
{
struct clk_init_data init;
struct berlin2_pll *pll;
pll = kzalloc(sizeof(*pll), GFP_KERNEL);
if (!pll)
return ERR_PTR(-ENOMEM);
/* copy pll_map to allow __initconst */
memcpy(&pll->map, map, sizeof(*map));
pll->base = base;
pll->hw.init = &init;
init.name = name;
init.ops = &berlin2_pll_ops;
init.parent_names = &parent_name;
init.num_parents = 1;
init.flags = flags;
return clk_register(NULL, &pll->hw);
}
/*
* Copyright (c) 2014 Marvell Technology Group Ltd.
*
* Alexandre Belloni <alexandre.belloni@free-electrons.com>
* Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along with
* this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef __BERLIN2_PLL_H
#define __BERLIN2_PLL_H
struct clk;
struct berlin2_pll_map {
const u8 vcodiv[16];
u8 mult;
u8 fbdiv_shift;
u8 rfdiv_shift;
u8 divsel_shift;
};
struct clk * __init
berlin2_pll_register(const struct berlin2_pll_map *map,
void __iomem *base, const char *name,
const char *parent_name, unsigned long flags);
#endif /* __BERLIN2_PLL_H */
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