diff options
Diffstat (limited to 'drivers/clk/meson/clk-mpll.c')
| -rw-r--r-- | drivers/clk/meson/clk-mpll.c | 94 |
1 files changed, 94 insertions, 0 deletions
diff --git a/drivers/clk/meson/clk-mpll.c b/drivers/clk/meson/clk-mpll.c new file mode 100644 index 000000000000..03af79005ddb --- /dev/null +++ b/drivers/clk/meson/clk-mpll.c @@ -0,0 +1,94 @@ +/* + * 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, +}; |