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linux/drivers/clk/meson/clk-mpll.h

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clk: meson: rework and clean drivers dependencies Initially, the meson clock directory only hosted 2 controllers drivers, for meson8 and gxbb. At the time, both used the same set of clock drivers so managing the dependencies was not a big concern. Since this ancient time, entropy did its job, controllers with different requirement and specific clock drivers have been added. Unfortunately, we did not do a great job at managing the dependencies between the controllers and the different clock drivers. Some drivers, such as clk-phase or vid-pll-div, are compiled even if they are useless on the target (meson8). As we are adding new controllers, we need to be able to pick a driver w/o pulling the whole thing. The patch aims to clean things up by: * providing a dedicated CONFIG_ for each clock drivers * allowing clock drivers to be compiled as a modules, if possible * stating explicitly which drivers are required by each controller. Signed-off-by: Jerome Brunet <jbrunet@baylibre.com> Signed-off-by: Neil Armstrong <narmstrong@baylibre.com> Link: https://lkml.kernel.org/r/20190201125841.26785-5-jbrunet@baylibre.com
2019-02-01 05:58:41 -07:00
/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright (c) 2019 BayLibre, SAS.
* Author: Jerome Brunet <jbrunet@baylibre.com>
*/
#ifndef __MESON_CLK_MPLL_H
#define __MESON_CLK_MPLL_H
#include <linux/clk-provider.h>
#include <linux/spinlock.h>
#include "parm.h"
struct meson_clk_mpll_data {
struct parm sdm;
struct parm sdm_en;
struct parm n2;
struct parm ssen;
struct parm misc;
clk: meson: mpll: add init callback and regs Until now (gx and axg), the mpll setting on boot (whatever the bootloader) was good enough to generate a clean fractional division. It is not the case on the g12a. While moving away from the vendor u-boot, it was noticed the fractional part of the divider was no longer applied. Like on the pll, some magic settings need to applied on the mpll register. This change adds the ability to do that on the mpll driver. Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
2019-05-13 05:31:12 -07:00
const struct reg_sequence *init_regs;
unsigned int init_count;
clk: meson: rework and clean drivers dependencies Initially, the meson clock directory only hosted 2 controllers drivers, for meson8 and gxbb. At the time, both used the same set of clock drivers so managing the dependencies was not a big concern. Since this ancient time, entropy did its job, controllers with different requirement and specific clock drivers have been added. Unfortunately, we did not do a great job at managing the dependencies between the controllers and the different clock drivers. Some drivers, such as clk-phase or vid-pll-div, are compiled even if they are useless on the target (meson8). As we are adding new controllers, we need to be able to pick a driver w/o pulling the whole thing. The patch aims to clean things up by: * providing a dedicated CONFIG_ for each clock drivers * allowing clock drivers to be compiled as a modules, if possible * stating explicitly which drivers are required by each controller. Signed-off-by: Jerome Brunet <jbrunet@baylibre.com> Signed-off-by: Neil Armstrong <narmstrong@baylibre.com> Link: https://lkml.kernel.org/r/20190201125841.26785-5-jbrunet@baylibre.com
2019-02-01 05:58:41 -07:00
spinlock_t *lock;
u8 flags;
};
#define CLK_MESON_MPLL_ROUND_CLOSEST BIT(0)
clk: meson: mpll: properly handle spread spectrum The bit 'SSEN' available on some MPLL DSS outputs is not related to the fractional part of the divider but to the function called 'Spread Spectrum'. This function might be used to solve EM issues by adding a jitter on clock signal. This widens the signal spectrum and weakens the peaks in it. While spread spectrum might be useful for some application, it is problematic for others, such as audio. This patch introduce a new flag to the MPLL driver to enable (or not) the spread spectrum function. Fixes: 1f737ffa13ef ("clk: meson: mpll: fix mpll0 fractional part ignored") Tested-by: Martin Blumenstingl<martin.blumenstingl@googlemail.com> Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
2019-05-13 05:31:09 -07:00
#define CLK_MESON_MPLL_SPREAD_SPECTRUM BIT(1)
clk: meson: rework and clean drivers dependencies Initially, the meson clock directory only hosted 2 controllers drivers, for meson8 and gxbb. At the time, both used the same set of clock drivers so managing the dependencies was not a big concern. Since this ancient time, entropy did its job, controllers with different requirement and specific clock drivers have been added. Unfortunately, we did not do a great job at managing the dependencies between the controllers and the different clock drivers. Some drivers, such as clk-phase or vid-pll-div, are compiled even if they are useless on the target (meson8). As we are adding new controllers, we need to be able to pick a driver w/o pulling the whole thing. The patch aims to clean things up by: * providing a dedicated CONFIG_ for each clock drivers * allowing clock drivers to be compiled as a modules, if possible * stating explicitly which drivers are required by each controller. Signed-off-by: Jerome Brunet <jbrunet@baylibre.com> Signed-off-by: Neil Armstrong <narmstrong@baylibre.com> Link: https://lkml.kernel.org/r/20190201125841.26785-5-jbrunet@baylibre.com
2019-02-01 05:58:41 -07:00
extern const struct clk_ops meson_clk_mpll_ro_ops;
extern const struct clk_ops meson_clk_mpll_ops;
#endif /* __MESON_CLK_MPLL_H */
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