1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * ARTPEC-6 clock initialization
4 *
5 * Copyright 2015-2016 Axis Communications AB.
6 */
7
8#include <linux/clk-provider.h>
9#include <linux/device.h>
10#include <linux/io.h>
11#include <linux/of.h>
12#include <linux/of_address.h>
13#include <linux/platform_device.h>
14#include <linux/slab.h>
15#include <dt-bindings/clock/axis,artpec6-clkctrl.h>
16
17#define NUM_I2S_CLOCKS 2
18
19struct artpec6_clkctrl_drvdata {
20	struct clk *clk_table[ARTPEC6_CLK_NUMCLOCKS];
21	void __iomem *syscon_base;
22	struct clk_onecell_data clk_data;
23	spinlock_t i2scfg_lock;
24};
25
26static struct artpec6_clkctrl_drvdata *clkdata;
27
28static const char *const i2s_clk_names[NUM_I2S_CLOCKS] = {
29	"i2s0",
30	"i2s1",
31};
32
33static const int i2s_clk_indexes[NUM_I2S_CLOCKS] = {
34	ARTPEC6_CLK_I2S0_CLK,
35	ARTPEC6_CLK_I2S1_CLK,
36};
37
38static void of_artpec6_clkctrl_setup(struct device_node *np)
39{
40	int i;
41	const char *sys_refclk_name;
42	u32 pll_mode, pll_m, pll_n;
43	struct clk **clks;
44
45	/* Mandatory parent clock. */
46	i = of_property_match_string(np, "clock-names", "sys_refclk");
47	if (i < 0)
48		return;
49
50	sys_refclk_name = of_clk_get_parent_name(np, i);
51
52	clkdata = kzalloc(sizeof(*clkdata), GFP_KERNEL);
53	if (!clkdata)
54		return;
55
56	clks = clkdata->clk_table;
57
58	for (i = 0; i < ARTPEC6_CLK_NUMCLOCKS; ++i)
59		clks[i] = ERR_PTR(-EPROBE_DEFER);
60
61	clkdata->syscon_base = of_iomap(np, 0);
62	BUG_ON(clkdata->syscon_base == NULL);
63
64	/* Read PLL1 factors configured by boot strap pins. */
65	pll_mode = (readl(clkdata->syscon_base) >> 6) & 3;
66	switch (pll_mode) {
67	case 0:		/* DDR3-2133 mode */
68		pll_m = 4;
69		pll_n = 85;
70		break;
71	case 1:		/* DDR3-1866 mode */
72		pll_m = 6;
73		pll_n = 112;
74		break;
75	case 2:		/* DDR3-1600 mode */
76		pll_m = 4;
77		pll_n = 64;
78		break;
79	case 3:		/* DDR3-1333 mode */
80		pll_m = 8;
81		pll_n = 106;
82		break;
83	}
84
85	clks[ARTPEC6_CLK_CPU] =
86	    clk_register_fixed_factor(NULL, "cpu", sys_refclk_name, 0, pll_n,
87				      pll_m);
88	clks[ARTPEC6_CLK_CPU_PERIPH] =
89	    clk_register_fixed_factor(NULL, "cpu_periph", "cpu", 0, 1, 2);
90
91	/* EPROBE_DEFER on the apb_clock is not handled in amba devices. */
92	clks[ARTPEC6_CLK_UART_PCLK] =
93	    clk_register_fixed_factor(NULL, "uart_pclk", "cpu", 0, 1, 8);
94	clks[ARTPEC6_CLK_UART_REFCLK] =
95	    clk_register_fixed_rate(NULL, "uart_ref", sys_refclk_name, 0,
96				    50000000);
97
98	clks[ARTPEC6_CLK_SPI_PCLK] =
99	    clk_register_fixed_factor(NULL, "spi_pclk", "cpu", 0, 1, 8);
100	clks[ARTPEC6_CLK_SPI_SSPCLK] =
101	    clk_register_fixed_rate(NULL, "spi_sspclk", sys_refclk_name, 0,
102				    50000000);
103
104	clks[ARTPEC6_CLK_DBG_PCLK] =
105	    clk_register_fixed_factor(NULL, "dbg_pclk", "cpu", 0, 1, 8);
106
107	clkdata->clk_data.clks = clkdata->clk_table;
108	clkdata->clk_data.clk_num = ARTPEC6_CLK_NUMCLOCKS;
109
110	of_clk_add_provider(np, of_clk_src_onecell_get, &clkdata->clk_data);
111}
112
113CLK_OF_DECLARE_DRIVER(artpec6_clkctrl, "axis,artpec6-clkctrl",
114		      of_artpec6_clkctrl_setup);
115
116static int artpec6_clkctrl_probe(struct platform_device *pdev)
117{
118	int propidx;
119	struct device_node *np = pdev->dev.of_node;
120	struct device *dev = &pdev->dev;
121	struct clk **clks = clkdata->clk_table;
122	const char *sys_refclk_name;
123	const char *i2s_refclk_name = NULL;
124	const char *frac_clk_name[2] = { NULL, NULL };
125	const char *i2s_mux_parents[2];
126	u32 muxreg;
127	int i;
128	int err = 0;
129
130	/* Mandatory parent clock. */
131	propidx = of_property_match_string(np, "clock-names", "sys_refclk");
132	if (propidx < 0)
133		return -EINVAL;
134
135	sys_refclk_name = of_clk_get_parent_name(np, propidx);
136
137	/* Find clock names of optional parent clocks. */
138	propidx = of_property_match_string(np, "clock-names", "i2s_refclk");
139	if (propidx >= 0)
140		i2s_refclk_name = of_clk_get_parent_name(np, propidx);
141
142	propidx = of_property_match_string(np, "clock-names", "frac_clk0");
143	if (propidx >= 0)
144		frac_clk_name[0] = of_clk_get_parent_name(np, propidx);
145	propidx = of_property_match_string(np, "clock-names", "frac_clk1");
146	if (propidx >= 0)
147		frac_clk_name[1] = of_clk_get_parent_name(np, propidx);
148
149	spin_lock_init(&clkdata->i2scfg_lock);
150
151	clks[ARTPEC6_CLK_NAND_CLKA] =
152	    clk_register_fixed_factor(dev, "nand_clka", "cpu", 0, 1, 8);
153	clks[ARTPEC6_CLK_NAND_CLKB] =
154	    clk_register_fixed_rate(dev, "nand_clkb", sys_refclk_name, 0,
155				    100000000);
156	clks[ARTPEC6_CLK_ETH_ACLK] =
157	    clk_register_fixed_factor(dev, "eth_aclk", "cpu", 0, 1, 4);
158	clks[ARTPEC6_CLK_DMA_ACLK] =
159	    clk_register_fixed_factor(dev, "dma_aclk", "cpu", 0, 1, 4);
160	clks[ARTPEC6_CLK_PTP_REF] =
161	    clk_register_fixed_rate(dev, "ptp_ref", sys_refclk_name, 0,
162				    100000000);
163	clks[ARTPEC6_CLK_SD_PCLK] =
164	    clk_register_fixed_rate(dev, "sd_pclk", sys_refclk_name, 0,
165				    100000000);
166	clks[ARTPEC6_CLK_SD_IMCLK] =
167	    clk_register_fixed_rate(dev, "sd_imclk", sys_refclk_name, 0,
168				    100000000);
169	clks[ARTPEC6_CLK_I2S_HST] =
170	    clk_register_fixed_factor(dev, "i2s_hst", "cpu", 0, 1, 8);
171
172	for (i = 0; i < NUM_I2S_CLOCKS; ++i) {
173		if (i2s_refclk_name && frac_clk_name[i]) {
174			i2s_mux_parents[0] = frac_clk_name[i];
175			i2s_mux_parents[1] = i2s_refclk_name;
176
177			clks[i2s_clk_indexes[i]] =
178			    clk_register_mux(dev, i2s_clk_names[i],
179					     i2s_mux_parents, 2,
180					     CLK_SET_RATE_NO_REPARENT |
181					     CLK_SET_RATE_PARENT,
182					     clkdata->syscon_base + 0x14, i, 1,
183					     0, &clkdata->i2scfg_lock);
184		} else if (frac_clk_name[i]) {
185			/* Lock the mux for internal clock reference. */
186			muxreg = readl(clkdata->syscon_base + 0x14);
187			muxreg &= ~BIT(i);
188			writel(muxreg, clkdata->syscon_base + 0x14);
189			clks[i2s_clk_indexes[i]] =
190			    clk_register_fixed_factor(dev, i2s_clk_names[i],
191						      frac_clk_name[i], 0, 1,
192						      1);
193		} else if (i2s_refclk_name) {
194			/* Lock the mux for external clock reference. */
195			muxreg = readl(clkdata->syscon_base + 0x14);
196			muxreg |= BIT(i);
197			writel(muxreg, clkdata->syscon_base + 0x14);
198			clks[i2s_clk_indexes[i]] =
199			    clk_register_fixed_factor(dev, i2s_clk_names[i],
200						      i2s_refclk_name, 0, 1, 1);
201		}
202	}
203
204	clks[ARTPEC6_CLK_I2C] =
205	    clk_register_fixed_rate(dev, "i2c", sys_refclk_name, 0, 100000000);
206
207	clks[ARTPEC6_CLK_SYS_TIMER] =
208	    clk_register_fixed_rate(dev, "timer", sys_refclk_name, 0,
209				    100000000);
210	clks[ARTPEC6_CLK_FRACDIV_IN] =
211	    clk_register_fixed_rate(dev, "fracdiv_in", sys_refclk_name, 0,
212				    600000000);
213
214	for (i = 0; i < ARTPEC6_CLK_NUMCLOCKS; ++i) {
215		if (IS_ERR(clks[i]) && PTR_ERR(clks[i]) != -EPROBE_DEFER) {
216			dev_err(dev,
217				"Failed to register clock at index %d err=%ld\n",
218				i, PTR_ERR(clks[i]));
219			err = PTR_ERR(clks[i]);
220		}
221	}
222
223	return err;
224}
225
226static const struct of_device_id artpec_clkctrl_of_match[] = {
227	{ .compatible = "axis,artpec6-clkctrl" },
228	{}
229};
230
231static struct platform_driver artpec6_clkctrl_driver = {
232	.probe = artpec6_clkctrl_probe,
233	.driver = {
234		   .name = "artpec6_clkctrl",
235		   .of_match_table = artpec_clkctrl_of_match,
236	},
237};
238
239builtin_platform_driver(artpec6_clkctrl_driver);
240