cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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clk-msc313-mpll.c (4467B)


      1// SPDX-License-Identifier: GPL-2.0
      2/*
      3 * MStar MSC313 MPLL driver
      4 *
      5 * Copyright (C) 2020 Daniel Palmer <daniel@thingy.jp>
      6 */
      7
      8#include <linux/platform_device.h>
      9#include <linux/of_address.h>
     10#include <linux/clk-provider.h>
     11#include <linux/regmap.h>
     12
     13#define REG_CONFIG1	0x8
     14#define REG_CONFIG2	0xc
     15
     16static const struct regmap_config msc313_mpll_regmap_config = {
     17	.reg_bits = 16,
     18	.val_bits = 16,
     19	.reg_stride = 4,
     20};
     21
     22static const struct reg_field config1_loop_div_first = REG_FIELD(REG_CONFIG1, 8, 9);
     23static const struct reg_field config1_input_div_first = REG_FIELD(REG_CONFIG1, 4, 5);
     24static const struct reg_field config2_output_div_first = REG_FIELD(REG_CONFIG2, 12, 13);
     25static const struct reg_field config2_loop_div_second = REG_FIELD(REG_CONFIG2, 0, 7);
     26
     27static const unsigned int output_dividers[] = {
     28	2, 3, 4, 5, 6, 7, 10
     29};
     30
     31#define NUMOUTPUTS (ARRAY_SIZE(output_dividers) + 1)
     32
     33struct msc313_mpll {
     34	struct clk_hw clk_hw;
     35	struct regmap_field *input_div;
     36	struct regmap_field *loop_div_first;
     37	struct regmap_field *loop_div_second;
     38	struct regmap_field *output_div;
     39	struct clk_hw_onecell_data *clk_data;
     40};
     41
     42#define to_mpll(_hw) container_of(_hw, struct msc313_mpll, clk_hw)
     43
     44static unsigned long msc313_mpll_recalc_rate(struct clk_hw *hw,
     45		unsigned long parent_rate)
     46{
     47	struct msc313_mpll *mpll = to_mpll(hw);
     48	unsigned int input_div, output_div, loop_first, loop_second;
     49	unsigned long output_rate;
     50
     51	regmap_field_read(mpll->input_div, &input_div);
     52	regmap_field_read(mpll->output_div, &output_div);
     53	regmap_field_read(mpll->loop_div_first, &loop_first);
     54	regmap_field_read(mpll->loop_div_second, &loop_second);
     55
     56	output_rate = parent_rate / (1 << input_div);
     57	output_rate *= (1 << loop_first) * max(loop_second, 1U);
     58	output_rate /= max(output_div, 1U);
     59
     60	return output_rate;
     61}
     62
     63static const struct clk_ops msc313_mpll_ops = {
     64	.recalc_rate = msc313_mpll_recalc_rate,
     65};
     66
     67static const struct clk_parent_data mpll_parent = {
     68	.index	= 0,
     69};
     70
     71static int msc313_mpll_probe(struct platform_device *pdev)
     72{
     73	void __iomem *base;
     74	struct msc313_mpll *mpll;
     75	struct clk_init_data clk_init = { };
     76	struct device *dev = &pdev->dev;
     77	struct regmap *regmap;
     78	char *outputname;
     79	struct clk_hw *divhw;
     80	int ret, i;
     81
     82	mpll = devm_kzalloc(dev, sizeof(*mpll), GFP_KERNEL);
     83	if (!mpll)
     84		return -ENOMEM;
     85
     86	base = devm_platform_ioremap_resource(pdev, 0);
     87	if (IS_ERR(base))
     88		return PTR_ERR(base);
     89
     90	regmap = devm_regmap_init_mmio(dev, base, &msc313_mpll_regmap_config);
     91	if (IS_ERR(regmap))
     92		return PTR_ERR(regmap);
     93
     94	mpll->input_div = devm_regmap_field_alloc(dev, regmap, config1_input_div_first);
     95	if (IS_ERR(mpll->input_div))
     96		return PTR_ERR(mpll->input_div);
     97	mpll->output_div = devm_regmap_field_alloc(dev, regmap, config2_output_div_first);
     98	if (IS_ERR(mpll->output_div))
     99		return PTR_ERR(mpll->output_div);
    100	mpll->loop_div_first = devm_regmap_field_alloc(dev, regmap, config1_loop_div_first);
    101	if (IS_ERR(mpll->loop_div_first))
    102		return PTR_ERR(mpll->loop_div_first);
    103	mpll->loop_div_second = devm_regmap_field_alloc(dev, regmap, config2_loop_div_second);
    104	if (IS_ERR(mpll->loop_div_second))
    105		return PTR_ERR(mpll->loop_div_second);
    106
    107	mpll->clk_data = devm_kzalloc(dev, struct_size(mpll->clk_data, hws,
    108			ARRAY_SIZE(output_dividers)), GFP_KERNEL);
    109	if (!mpll->clk_data)
    110		return -ENOMEM;
    111
    112	clk_init.name = dev_name(dev);
    113	clk_init.ops = &msc313_mpll_ops;
    114	clk_init.parent_data = &mpll_parent;
    115	clk_init.num_parents = 1;
    116	mpll->clk_hw.init = &clk_init;
    117
    118	ret = devm_clk_hw_register(dev, &mpll->clk_hw);
    119	if (ret)
    120		return ret;
    121
    122	mpll->clk_data->num = NUMOUTPUTS;
    123	mpll->clk_data->hws[0] = &mpll->clk_hw;
    124
    125	for (i = 0; i < ARRAY_SIZE(output_dividers); i++) {
    126		outputname = devm_kasprintf(dev, GFP_KERNEL, "%s_div_%u",
    127				clk_init.name, output_dividers[i]);
    128		if (!outputname)
    129			return -ENOMEM;
    130		divhw = devm_clk_hw_register_fixed_factor(dev, outputname,
    131				clk_init.name, 0, 1, output_dividers[i]);
    132		if (IS_ERR(divhw))
    133			return PTR_ERR(divhw);
    134		mpll->clk_data->hws[i + 1] = divhw;
    135	}
    136
    137	platform_set_drvdata(pdev, mpll);
    138
    139	return devm_of_clk_add_hw_provider(&pdev->dev, of_clk_hw_onecell_get,
    140			mpll->clk_data);
    141}
    142
    143static const struct of_device_id msc313_mpll_of_match[] = {
    144	{ .compatible = "mstar,msc313-mpll", },
    145	{}
    146};
    147
    148static struct platform_driver msc313_mpll_driver = {
    149	.driver = {
    150		.name = "mstar-msc313-mpll",
    151		.of_match_table = msc313_mpll_of_match,
    152	},
    153	.probe = msc313_mpll_probe,
    154};
    155builtin_platform_driver(msc313_mpll_driver);