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
19 struct 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
26 static struct artpec6_clkctrl_drvdata *clkdata;
27
28 static const char *const i2s_clk_names[NUM_I2S_CLOCKS] = {
29 "i2s0",
30 "i2s1",
31 };
32
33 static const int i2s_clk_indexes[NUM_I2S_CLOCKS] = {
34 ARTPEC6_CLK_I2S0_CLK,
35 ARTPEC6_CLK_I2S1_CLK,
36 };
37
of_artpec6_clkctrl_setup(struct device_node * np)38 static 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
113 CLK_OF_DECLARE_DRIVER(artpec6_clkctrl, "axis,artpec6-clkctrl",
114 of_artpec6_clkctrl_setup);
115
artpec6_clkctrl_probe(struct platform_device * pdev)116 static 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
226 static const struct of_device_id artpec_clkctrl_of_match[] = {
227 { .compatible = "axis,artpec6-clkctrl" },
228 {}
229 };
230
231 static 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
239 builtin_platform_driver(artpec6_clkctrl_driver);
240