tegrakernel/kernel/kernel-4.9/drivers/clk/meson/clk-mpll.c

95 lines
3.5 KiB
C

/*
* This file is provided under a dual BSD/GPLv2 license. When using or
* redistributing this file, you may do so under either license.
*
* GPL LICENSE SUMMARY
*
* Copyright (c) 2016 AmLogic, Inc.
* Author: Michael Turquette <mturquette@baylibre.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of version 2 of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that 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, write to the Free Software
* Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
* The full GNU General Public License is included in this distribution
* in the file called COPYING
*
* BSD LICENSE
*
* Copyright (c) 2016 AmLogic, Inc.
* Author: Michael Turquette <mturquette@baylibre.com>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* * Neither the name of Intel Corporation nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*
* MultiPhase Locked Loops are outputs from a PLL with additional frequency
* scaling capabilities. MPLL rates are calculated as:
*
* f(N2_integer, SDM_IN ) = 2.0G/(N2_integer + SDM_IN/16384)
*/
#include <linux/clk-provider.h>
#include "clkc.h"
#define SDM_MAX 16384
#define to_meson_clk_mpll(_hw) container_of(_hw, struct meson_clk_mpll, hw)
static unsigned long mpll_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
struct meson_clk_mpll *mpll = to_meson_clk_mpll(hw);
struct parm *p;
unsigned long rate = 0;
unsigned long reg, sdm, n2;
p = &mpll->sdm;
reg = readl(mpll->base + p->reg_off);
sdm = PARM_GET(p->width, p->shift, reg);
p = &mpll->n2;
reg = readl(mpll->base + p->reg_off);
n2 = PARM_GET(p->width, p->shift, reg);
rate = (parent_rate * SDM_MAX) / ((SDM_MAX * n2) + sdm);
return rate;
}
const struct clk_ops meson_clk_mpll_ro_ops = {
.recalc_rate = mpll_recalc_rate,
};