1 /*
2  * Renesas RCar Gen2 CPG MSSR driver
3  *
4  * Copyright (C) 2017 Marek Vasut <marek.vasut@gmail.com>
5  *
6  * Based on the following driver from Linux kernel:
7  * r8a7796 Clock Pulse Generator / Module Standby and Software Reset
8  *
9  * Copyright (C) 2016 Glider bvba
10  *
11  * SPDX-License-Identifier:	GPL-2.0+
12  */
13 
14 #include <common.h>
15 #include <clk-uclass.h>
16 #include <dm.h>
17 #include <errno.h>
18 #include <asm/io.h>
19 
20 #include <dt-bindings/clock/renesas-cpg-mssr.h>
21 
22 #include "renesas-cpg-mssr.h"
23 #include "rcar-gen2-cpg.h"
24 
25 #define CPG_RST_MODEMR		0x0060
26 
27 #define CPG_PLL0CR		0x00d8
28 #define CPG_SDCKCR		0x0074
29 
30 struct clk_div_table {
31 	u8	val;
32 	u8	div;
33 };
34 
35 /* SDHI divisors */
36 static const struct clk_div_table cpg_sdh_div_table[] = {
37 	{  0,  2 }, {  1,  3 }, {  2,  4 }, {  3,  6 },
38 	{  4,  8 }, {  5, 12 }, {  6, 16 }, {  7, 18 },
39 	{  8, 24 }, { 10, 36 }, { 11, 48 }, {  0,  0 },
40 };
41 
42 static const struct clk_div_table cpg_sd01_div_table[] = {
43 	{  4,  8 }, {  5, 12 }, {  6, 16 }, {  7, 18 },
44 	{  8, 24 }, { 10, 36 }, { 11, 48 }, { 12, 10 },
45 	{  0,  0 },
46 };
47 
48 static u8 gen2_clk_get_sdh_div(const struct clk_div_table *table, u8 div)
49 {
50 	while ((*table++).val) {
51 		if ((*table).div == div)
52 			return div;
53 	}
54 	return 0xff;
55 }
56 
57 static int gen2_clk_enable(struct clk *clk)
58 {
59 	struct gen2_clk_priv *priv = dev_get_priv(clk->dev);
60 
61 	return renesas_clk_endisable(clk, priv->base, true);
62 }
63 
64 static int gen2_clk_disable(struct clk *clk)
65 {
66 	struct gen2_clk_priv *priv = dev_get_priv(clk->dev);
67 
68 	return renesas_clk_endisable(clk, priv->base, false);
69 }
70 
71 static ulong gen2_clk_get_rate(struct clk *clk)
72 {
73 	struct gen2_clk_priv *priv = dev_get_priv(clk->dev);
74 	struct cpg_mssr_info *info = priv->info;
75 	struct clk parent;
76 	const struct cpg_core_clk *core;
77 	const struct rcar_gen2_cpg_pll_config *pll_config =
78 					priv->cpg_pll_config;
79 	u32 value, mult, div, rate = 0;
80 	int ret;
81 
82 	debug("%s[%i] Clock: id=%lu\n", __func__, __LINE__, clk->id);
83 
84 	ret = renesas_clk_get_parent(clk, info, &parent);
85 	if (ret) {
86 		printf("%s[%i] parent fail, ret=%i\n", __func__, __LINE__, ret);
87 		return ret;
88 	}
89 
90 	if (renesas_clk_is_mod(clk)) {
91 		rate = gen2_clk_get_rate(&parent);
92 		debug("%s[%i] MOD clk: parent=%lu => rate=%u\n",
93 		      __func__, __LINE__, parent.id, rate);
94 		return rate;
95 	}
96 
97 	ret = renesas_clk_get_core(clk, info, &core);
98 	if (ret)
99 		return ret;
100 
101 	switch (core->type) {
102 	case CLK_TYPE_IN:
103 		if (core->id == info->clk_extal_id) {
104 			rate = clk_get_rate(&priv->clk_extal);
105 			debug("%s[%i] EXTAL clk: rate=%u\n",
106 			      __func__, __LINE__, rate);
107 			return rate;
108 		}
109 
110 		if (core->id == info->clk_extal_usb_id) {
111 			rate = clk_get_rate(&priv->clk_extal_usb);
112 			debug("%s[%i] EXTALR clk: rate=%u\n",
113 			      __func__, __LINE__, rate);
114 			return rate;
115 		}
116 
117 		return -EINVAL;
118 
119 	case CLK_TYPE_FF:
120 		rate = (gen2_clk_get_rate(&parent) * core->mult) / core->div;
121 		debug("%s[%i] FIXED clk: parent=%i div=%i mul=%i => rate=%u\n",
122 		      __func__, __LINE__,
123 		      core->parent, core->mult, core->div, rate);
124 		return rate;
125 
126 	case CLK_TYPE_DIV6P1:	/* DIV6 Clock with 1 parent clock */
127 		value = (readl(priv->base + core->offset) & 0x3f) + 1;
128 		rate = gen2_clk_get_rate(&parent) / value;
129 		debug("%s[%i] DIV6P1 clk: parent=%i div=%i => rate=%u\n",
130 		      __func__, __LINE__,
131 		      core->parent, value, rate);
132 		return rate;
133 
134 	case CLK_TYPE_GEN2_MAIN:
135 		rate = gen2_clk_get_rate(&parent) / pll_config->extal_div;
136 		debug("%s[%i] MAIN clk: parent=%i extal_div=%i => rate=%u\n",
137 		      __func__, __LINE__,
138 		      core->parent, pll_config->extal_div, rate);
139 		return rate;
140 
141 	case CLK_TYPE_GEN2_PLL0:
142 		/*
143 		 * PLL0 is a  configurable multiplier clock except on R-Car
144 		 * V2H/E2. Register the PLL0 clock as a fixed factor clock for
145 		 * now as there's no generic multiplier clock implementation and
146 		 * we  currently  have no need to change  the multiplier value.
147 		 */
148 		mult = pll_config->pll0_mult;
149 		if (!mult) {
150 			value = readl(priv->base + CPG_PLL0CR);
151 			mult = (((value >> 24) & 0x7f) + 1) * 2;
152 		}
153 
154 		rate = (gen2_clk_get_rate(&parent) * mult) / info->pll0_div;
155 		debug("%s[%i] PLL0 clk: parent=%i mult=%u => rate=%u\n",
156 		      __func__, __LINE__, core->parent, mult, rate);
157 		return rate;
158 
159 	case CLK_TYPE_GEN2_PLL1:
160 		rate = (gen2_clk_get_rate(&parent) * pll_config->pll1_mult) / 2;
161 		debug("%s[%i] PLL1 clk: parent=%i mul=%i => rate=%u\n",
162 		      __func__, __LINE__,
163 		      core->parent, pll_config->pll1_mult, rate);
164 		return rate;
165 
166 	case CLK_TYPE_GEN2_PLL3:
167 		rate = gen2_clk_get_rate(&parent) * pll_config->pll3_mult;
168 		debug("%s[%i] PLL3 clk: parent=%i mul=%i => rate=%u\n",
169 		      __func__, __LINE__,
170 		      core->parent, pll_config->pll3_mult, rate);
171 		return rate;
172 
173 	case CLK_TYPE_GEN2_SDH:
174 		value = (readl(priv->base + CPG_SDCKCR) >> 8) & 0xf;
175 		div = gen2_clk_get_sdh_div(cpg_sdh_div_table, value);
176 		rate = gen2_clk_get_rate(&parent) / div;
177 		debug("%s[%i] SDH clk: parent=%i div=%i => rate=%u\n",
178 		      __func__, __LINE__,
179 		      core->parent, div, rate);
180 		return rate;
181 
182 	case CLK_TYPE_GEN2_SD0:
183 		value = (readl(priv->base + CPG_SDCKCR) >> 4) & 0xf;
184 		div = gen2_clk_get_sdh_div(cpg_sd01_div_table, value);
185 		rate = gen2_clk_get_rate(&parent) / div;
186 		debug("%s[%i] SD0 clk: parent=%i div=%i => rate=%u\n",
187 		      __func__, __LINE__,
188 		      core->parent, div, rate);
189 		return rate;
190 
191 	case CLK_TYPE_GEN2_SD1:
192 		value = (readl(priv->base + CPG_SDCKCR) >> 0) & 0xf;
193 		div = gen2_clk_get_sdh_div(cpg_sd01_div_table, value);
194 		rate = gen2_clk_get_rate(&parent) / div;
195 		debug("%s[%i] SD1 clk: parent=%i div=%i => rate=%u\n",
196 		      __func__, __LINE__,
197 		      core->parent, div, rate);
198 		return rate;
199 	}
200 
201 	printf("%s[%i] unknown fail\n", __func__, __LINE__);
202 
203 	return -ENOENT;
204 }
205 
206 static ulong gen2_clk_set_rate(struct clk *clk, ulong rate)
207 {
208 	return gen2_clk_get_rate(clk);
209 }
210 
211 static int gen2_clk_of_xlate(struct clk *clk, struct ofnode_phandle_args *args)
212 {
213 	if (args->args_count != 2) {
214 		debug("Invaild args_count: %d\n", args->args_count);
215 		return -EINVAL;
216 	}
217 
218 	clk->id = (args->args[0] << 16) | args->args[1];
219 
220 	return 0;
221 }
222 
223 const struct clk_ops gen2_clk_ops = {
224 	.enable		= gen2_clk_enable,
225 	.disable	= gen2_clk_disable,
226 	.get_rate	= gen2_clk_get_rate,
227 	.set_rate	= gen2_clk_set_rate,
228 	.of_xlate	= gen2_clk_of_xlate,
229 };
230 
231 int gen2_clk_probe(struct udevice *dev)
232 {
233 	struct gen2_clk_priv *priv = dev_get_priv(dev);
234 	struct cpg_mssr_info *info =
235 		(struct cpg_mssr_info *)dev_get_driver_data(dev);
236 	fdt_addr_t rst_base;
237 	u32 cpg_mode;
238 	int ret;
239 
240 	priv->base = (struct gen2_base *)devfdt_get_addr(dev);
241 	if (!priv->base)
242 		return -EINVAL;
243 
244 	priv->info = info;
245 	ret = fdt_node_offset_by_compatible(gd->fdt_blob, -1, info->reset_node);
246 	if (ret < 0)
247 		return ret;
248 
249 	rst_base = fdtdec_get_addr(gd->fdt_blob, ret, "reg");
250 	if (rst_base == FDT_ADDR_T_NONE)
251 		return -EINVAL;
252 
253 	cpg_mode = readl(rst_base + CPG_RST_MODEMR);
254 
255 	priv->cpg_pll_config =
256 		(struct rcar_gen2_cpg_pll_config *)info->get_pll_config(cpg_mode);
257 	if (!priv->cpg_pll_config->extal_div)
258 		return -EINVAL;
259 
260 	ret = clk_get_by_name(dev, "extal", &priv->clk_extal);
261 	if (ret < 0)
262 		return ret;
263 
264 	if (info->extal_usb_node) {
265 		ret = clk_get_by_name(dev, info->extal_usb_node,
266 				      &priv->clk_extal_usb);
267 		if (ret < 0)
268 			return ret;
269 	}
270 
271 	return 0;
272 }
273 
274 int gen2_clk_remove(struct udevice *dev)
275 {
276 	struct gen2_clk_priv *priv = dev_get_priv(dev);
277 
278 	return renesas_clk_remove(priv->base, priv->info);
279 }
280