xref: /openbmc/u-boot/drivers/clk/clk_meson_axg.c (revision dd1033e4)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * (C) Copyright 2018 - Beniamino Galvani <b.galvani@gmail.com>
4  * (C) Copyright 2018 - BayLibre, SAS
5  * Author: Neil Armstrong <narmstrong@baylibre.com>
6  */
7 
8 #include <common.h>
9 #include <asm/arch/clock-axg.h>
10 #include <asm/io.h>
11 #include <clk-uclass.h>
12 #include <dm.h>
13 #include <regmap.h>
14 #include <syscon.h>
15 #include <div64.h>
16 #include <dt-bindings/clock/axg-clkc.h>
17 #include "clk_meson.h"
18 
19 #define XTAL_RATE 24000000
20 
21 struct meson_clk {
22 	struct regmap *map;
23 };
24 
25 static ulong meson_clk_get_rate_by_id(struct clk *clk, unsigned long id);
26 
27 static struct meson_gate gates[] = {
28 	/* Everything Else (EE) domain gates */
29 	MESON_GATE(CLKID_SPICC0, HHI_GCLK_MPEG0, 8),
30 	MESON_GATE(CLKID_I2C, HHI_GCLK_MPEG0, 9),
31 	MESON_GATE(CLKID_UART0, HHI_GCLK_MPEG0, 13),
32 	MESON_GATE(CLKID_SPICC1, HHI_GCLK_MPEG0, 15),
33 	MESON_GATE(CLKID_SD_EMMC_B, HHI_GCLK_MPEG0, 25),
34 	MESON_GATE(CLKID_SD_EMMC_C, HHI_GCLK_MPEG0, 26),
35 	MESON_GATE(CLKID_ETH, HHI_GCLK_MPEG1, 3),
36 	MESON_GATE(CLKID_UART1, HHI_GCLK_MPEG1, 16),
37 
38 	/* Always On (AO) domain gates */
39 	MESON_GATE(CLKID_AO_I2C, HHI_GCLK_AO, 4),
40 
41 	/* PLL Gates */
42 	/* CLKID_FCLK_DIV2 is critical for the SCPI Processor */
43 	MESON_GATE(CLKID_MPLL2, HHI_MPLL_CNTL9, 14),
44 	/* CLKID_CLK81 is critical for the system */
45 
46 	/* Peripheral Gates */
47 	MESON_GATE(CLKID_SD_EMMC_B_CLK0, HHI_SD_EMMC_CLK_CNTL, 23),
48 	MESON_GATE(CLKID_SD_EMMC_C_CLK0, HHI_NAND_CLK_CNTL, 7),
49 };
50 
51 static int meson_set_gate(struct clk *clk, bool on)
52 {
53 	struct meson_clk *priv = dev_get_priv(clk->dev);
54 	struct meson_gate *gate;
55 
56 	if (clk->id >= ARRAY_SIZE(gates))
57 		return -ENOENT;
58 
59 	gate = &gates[clk->id];
60 
61 	if (gate->reg == 0)
62 		return 0;
63 
64 	regmap_update_bits(priv->map, gate->reg,
65 			   BIT(gate->bit), on ? BIT(gate->bit) : 0);
66 
67 	return 0;
68 }
69 
70 static int meson_clk_enable(struct clk *clk)
71 {
72 	return meson_set_gate(clk, true);
73 }
74 
75 static int meson_clk_disable(struct clk *clk)
76 {
77 	return meson_set_gate(clk, false);
78 }
79 
80 static unsigned long meson_clk81_get_rate(struct clk *clk)
81 {
82 	struct meson_clk *priv = dev_get_priv(clk->dev);
83 	unsigned long parent_rate;
84 	uint reg;
85 	int parents[] = {
86 		-1,
87 		-1,
88 		CLKID_FCLK_DIV7,
89 		CLKID_MPLL1,
90 		CLKID_MPLL2,
91 		CLKID_FCLK_DIV4,
92 		CLKID_FCLK_DIV3,
93 		CLKID_FCLK_DIV5
94 	};
95 
96 	/* mux */
97 	regmap_read(priv->map, HHI_MPEG_CLK_CNTL, &reg);
98 	reg = (reg >> 12) & 7;
99 
100 	switch (reg) {
101 	case 0:
102 		parent_rate = XTAL_RATE;
103 		break;
104 	case 1:
105 		return -ENOENT;
106 	default:
107 		parent_rate = meson_clk_get_rate_by_id(clk, parents[reg]);
108 	}
109 
110 	/* divider */
111 	regmap_read(priv->map, HHI_MPEG_CLK_CNTL, &reg);
112 	reg = reg & ((1 << 7) - 1);
113 
114 	return parent_rate / reg;
115 }
116 
117 static long mpll_rate_from_params(unsigned long parent_rate,
118 				  unsigned long sdm,
119 				  unsigned long n2)
120 {
121 	unsigned long divisor = (SDM_DEN * n2) + sdm;
122 
123 	if (n2 < N2_MIN)
124 		return -EINVAL;
125 
126 	return DIV_ROUND_UP_ULL((u64)parent_rate * SDM_DEN, divisor);
127 }
128 
129 static struct parm meson_mpll0_parm[3] = {
130 	{HHI_MPLL_CNTL7, 0, 14}, /* psdm */
131 	{HHI_MPLL_CNTL7, 16, 9}, /* pn2 */
132 };
133 
134 static struct parm meson_mpll1_parm[3] = {
135 	{HHI_MPLL_CNTL8, 0, 14}, /* psdm */
136 	{HHI_MPLL_CNTL8, 16, 9}, /* pn2 */
137 };
138 
139 static struct parm meson_mpll2_parm[3] = {
140 	{HHI_MPLL_CNTL9, 0, 14}, /* psdm */
141 	{HHI_MPLL_CNTL9, 16, 9}, /* pn2 */
142 };
143 
144 /*
145  * MultiPhase Locked Loops are outputs from a PLL with additional frequency
146  * scaling capabilities. MPLL rates are calculated as:
147  *
148  * f(N2_integer, SDM_IN ) = 2.0G/(N2_integer + SDM_IN/16384)
149  */
150 static ulong meson_mpll_get_rate(struct clk *clk, unsigned long id)
151 {
152 	struct meson_clk *priv = dev_get_priv(clk->dev);
153 	struct parm *psdm, *pn2;
154 	unsigned long sdm, n2;
155 	unsigned long parent_rate;
156 	uint reg;
157 
158 	switch (id) {
159 	case CLKID_MPLL0:
160 		psdm = &meson_mpll0_parm[0];
161 		pn2 = &meson_mpll0_parm[1];
162 		break;
163 	case CLKID_MPLL1:
164 		psdm = &meson_mpll1_parm[0];
165 		pn2 = &meson_mpll1_parm[1];
166 		break;
167 	case CLKID_MPLL2:
168 		psdm = &meson_mpll2_parm[0];
169 		pn2 = &meson_mpll2_parm[1];
170 		break;
171 	default:
172 		return -ENOENT;
173 	}
174 
175 	parent_rate = meson_clk_get_rate_by_id(clk, CLKID_FIXED_PLL);
176 	if (IS_ERR_VALUE(parent_rate))
177 		return parent_rate;
178 
179 	regmap_read(priv->map, psdm->reg_off, &reg);
180 	sdm = PARM_GET(psdm->width, psdm->shift, reg);
181 
182 	regmap_read(priv->map, pn2->reg_off, &reg);
183 	n2 = PARM_GET(pn2->width, pn2->shift, reg);
184 
185 	return mpll_rate_from_params(parent_rate, sdm, n2);
186 }
187 
188 static struct parm meson_fixed_pll_parm[3] = {
189 	{HHI_MPLL_CNTL, 0, 9}, /* pm */
190 	{HHI_MPLL_CNTL, 9, 5}, /* pn */
191 	{HHI_MPLL_CNTL, 16, 2}, /* pod */
192 };
193 
194 static struct parm meson_sys_pll_parm[3] = {
195 	{HHI_SYS_PLL_CNTL, 0, 9}, /* pm */
196 	{HHI_SYS_PLL_CNTL, 9, 5}, /* pn */
197 	{HHI_SYS_PLL_CNTL, 16, 2}, /* pod */
198 };
199 
200 static ulong meson_pll_get_rate(struct clk *clk, unsigned long id)
201 {
202 	struct meson_clk *priv = dev_get_priv(clk->dev);
203 	struct parm *pm, *pn, *pod;
204 	unsigned long parent_rate_mhz = XTAL_RATE / 1000000;
205 	u16 n, m, od;
206 	uint reg;
207 
208 	switch (id) {
209 	case CLKID_FIXED_PLL:
210 		pm = &meson_fixed_pll_parm[0];
211 		pn = &meson_fixed_pll_parm[1];
212 		pod = &meson_fixed_pll_parm[2];
213 		break;
214 	case CLKID_SYS_PLL:
215 		pm = &meson_sys_pll_parm[0];
216 		pn = &meson_sys_pll_parm[1];
217 		pod = &meson_sys_pll_parm[2];
218 		break;
219 	default:
220 		return -ENOENT;
221 	}
222 
223 	regmap_read(priv->map, pn->reg_off, &reg);
224 	n = PARM_GET(pn->width, pn->shift, reg);
225 
226 	regmap_read(priv->map, pm->reg_off, &reg);
227 	m = PARM_GET(pm->width, pm->shift, reg);
228 
229 	regmap_read(priv->map, pod->reg_off, &reg);
230 	od = PARM_GET(pod->width, pod->shift, reg);
231 
232 	return ((parent_rate_mhz * m / n) >> od) * 1000000;
233 }
234 
235 static ulong meson_clk_get_rate_by_id(struct clk *clk, unsigned long id)
236 {
237 	ulong rate;
238 
239 	switch (id) {
240 	case CLKID_FIXED_PLL:
241 	case CLKID_SYS_PLL:
242 		rate = meson_pll_get_rate(clk, id);
243 		break;
244 	case CLKID_FCLK_DIV2:
245 		rate = meson_pll_get_rate(clk, CLKID_FIXED_PLL) / 2;
246 		break;
247 	case CLKID_FCLK_DIV3:
248 		rate = meson_pll_get_rate(clk, CLKID_FIXED_PLL) / 3;
249 		break;
250 	case CLKID_FCLK_DIV4:
251 		rate = meson_pll_get_rate(clk, CLKID_FIXED_PLL) / 4;
252 		break;
253 	case CLKID_FCLK_DIV5:
254 		rate = meson_pll_get_rate(clk, CLKID_FIXED_PLL) / 5;
255 		break;
256 	case CLKID_FCLK_DIV7:
257 		rate = meson_pll_get_rate(clk, CLKID_FIXED_PLL) / 7;
258 		break;
259 	case CLKID_MPLL0:
260 	case CLKID_MPLL1:
261 	case CLKID_MPLL2:
262 		rate = meson_mpll_get_rate(clk, id);
263 		break;
264 	case CLKID_CLK81:
265 		rate = meson_clk81_get_rate(clk);
266 		break;
267 	default:
268 		if (gates[id].reg != 0) {
269 			/* a clock gate */
270 			rate = meson_clk81_get_rate(clk);
271 			break;
272 		}
273 		return -ENOENT;
274 	}
275 
276 	debug("clock %lu has rate %lu\n", id, rate);
277 	return rate;
278 }
279 
280 static ulong meson_clk_get_rate(struct clk *clk)
281 {
282 	return meson_clk_get_rate_by_id(clk, clk->id);
283 }
284 
285 static int meson_clk_probe(struct udevice *dev)
286 {
287 	struct meson_clk *priv = dev_get_priv(dev);
288 
289 	priv->map = syscon_node_to_regmap(dev_get_parent(dev)->node);
290 	if (IS_ERR(priv->map))
291 		return PTR_ERR(priv->map);
292 
293 	debug("meson-clk-axg: probed\n");
294 
295 	return 0;
296 }
297 
298 static struct clk_ops meson_clk_ops = {
299 	.disable	= meson_clk_disable,
300 	.enable		= meson_clk_enable,
301 	.get_rate	= meson_clk_get_rate,
302 };
303 
304 static const struct udevice_id meson_clk_ids[] = {
305 	{ .compatible = "amlogic,axg-clkc" },
306 	{ }
307 };
308 
309 U_BOOT_DRIVER(meson_clk_axg) = {
310 	.name		= "meson_clk_axg",
311 	.id		= UCLASS_CLK,
312 	.of_match	= meson_clk_ids,
313 	.priv_auto_alloc_size = sizeof(struct meson_clk),
314 	.ops		= &meson_clk_ops,
315 	.probe		= meson_clk_probe,
316 };
317