xref: /openbmc/linux/drivers/clk/mvebu/kirkwood.c (revision 10529938)
1 /*
2  * Marvell Kirkwood SoC clocks
3  *
4  * Copyright (C) 2012 Marvell
5  *
6  * Gregory CLEMENT <gregory.clement@free-electrons.com>
7  * Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
8  * Andrew Lunn <andrew@lunn.ch>
9  *
10  * This file is licensed under the terms of the GNU General Public
11  * License version 2.  This program is licensed "as is" without any
12  * warranty of any kind, whether express or implied.
13  */
14 
15 #include <linux/kernel.h>
16 #include <linux/slab.h>
17 #include <linux/clk-provider.h>
18 #include <linux/io.h>
19 #include <linux/of.h>
20 #include <linux/of_address.h>
21 #include "common.h"
22 
23 /*
24  * Core Clocks
25  *
26  * Kirkwood PLL sample-at-reset configuration
27  * (6180 has different SAR layout than other Kirkwood SoCs)
28  *
29  * SAR0[4:3,22,1] : CPU frequency (6281,6292,6282)
30  *	4  =  600 MHz
31  *	6  =  800 MHz
32  *	7  = 1000 MHz
33  *	9  = 1200 MHz
34  *	12 = 1500 MHz
35  *	13 = 1600 MHz
36  *	14 = 1800 MHz
37  *	15 = 2000 MHz
38  *	others reserved.
39  *
40  * SAR0[19,10:9] : CPU to L2 Clock divider ratio (6281,6292,6282)
41  *	1 = (1/2) * CPU
42  *	3 = (1/3) * CPU
43  *	5 = (1/4) * CPU
44  *	others reserved.
45  *
46  * SAR0[8:5] : CPU to DDR DRAM Clock divider ratio (6281,6292,6282)
47  *	2 = (1/2) * CPU
48  *	4 = (1/3) * CPU
49  *	6 = (1/4) * CPU
50  *	7 = (2/9) * CPU
51  *	8 = (1/5) * CPU
52  *	9 = (1/6) * CPU
53  *	others reserved.
54  *
55  * SAR0[4:2] : Kirkwood 6180 cpu/l2/ddr clock configuration (6180 only)
56  *	5 = [CPU =  600 MHz, L2 = (1/2) * CPU, DDR = 200 MHz = (1/3) * CPU]
57  *	6 = [CPU =  800 MHz, L2 = (1/2) * CPU, DDR = 200 MHz = (1/4) * CPU]
58  *	7 = [CPU = 1000 MHz, L2 = (1/2) * CPU, DDR = 200 MHz = (1/5) * CPU]
59  *	others reserved.
60  *
61  * SAR0[21] : TCLK frequency
62  *	0 = 200 MHz
63  *	1 = 166 MHz
64  *	others reserved.
65  */
66 
67 #define SAR_KIRKWOOD_CPU_FREQ(x)	\
68 	(((x & (1 <<  1)) >>  1) |	\
69 	 ((x & (1 << 22)) >> 21) |	\
70 	 ((x & (3 <<  3)) >>  1))
71 #define SAR_KIRKWOOD_L2_RATIO(x)	\
72 	(((x & (3 <<  9)) >> 9) |	\
73 	 (((x & (1 << 19)) >> 17)))
74 #define SAR_KIRKWOOD_DDR_RATIO		5
75 #define SAR_KIRKWOOD_DDR_RATIO_MASK	0xf
76 #define SAR_MV88F6180_CLK		2
77 #define SAR_MV88F6180_CLK_MASK		0x7
78 #define SAR_KIRKWOOD_TCLK_FREQ		21
79 #define SAR_KIRKWOOD_TCLK_FREQ_MASK	0x1
80 
81 enum { KIRKWOOD_CPU_TO_L2, KIRKWOOD_CPU_TO_DDR };
82 
83 static const struct coreclk_ratio kirkwood_coreclk_ratios[] __initconst = {
84 	{ .id = KIRKWOOD_CPU_TO_L2, .name = "l2clk", },
85 	{ .id = KIRKWOOD_CPU_TO_DDR, .name = "ddrclk", }
86 };
87 
88 static u32 __init kirkwood_get_tclk_freq(void __iomem *sar)
89 {
90 	u32 opt = (readl(sar) >> SAR_KIRKWOOD_TCLK_FREQ) &
91 		SAR_KIRKWOOD_TCLK_FREQ_MASK;
92 	return (opt) ? 166666667 : 200000000;
93 }
94 
95 static const u32 kirkwood_cpu_freqs[] __initconst = {
96 	0, 0, 0, 0,
97 	600000000,
98 	0,
99 	800000000,
100 	1000000000,
101 	0,
102 	1200000000,
103 	0, 0,
104 	1500000000,
105 	1600000000,
106 	1800000000,
107 	2000000000
108 };
109 
110 static u32 __init kirkwood_get_cpu_freq(void __iomem *sar)
111 {
112 	u32 opt = SAR_KIRKWOOD_CPU_FREQ(readl(sar));
113 	return kirkwood_cpu_freqs[opt];
114 }
115 
116 static const int kirkwood_cpu_l2_ratios[8][2] __initconst = {
117 	{ 0, 1 }, { 1, 2 }, { 0, 1 }, { 1, 3 },
118 	{ 0, 1 }, { 1, 4 }, { 0, 1 }, { 0, 1 }
119 };
120 
121 static const int kirkwood_cpu_ddr_ratios[16][2] __initconst = {
122 	{ 0, 1 }, { 0, 1 }, { 1, 2 }, { 0, 1 },
123 	{ 1, 3 }, { 0, 1 }, { 1, 4 }, { 2, 9 },
124 	{ 1, 5 }, { 1, 6 }, { 0, 1 }, { 0, 1 },
125 	{ 0, 1 }, { 0, 1 }, { 0, 1 }, { 0, 1 }
126 };
127 
128 static void __init kirkwood_get_clk_ratio(
129 	void __iomem *sar, int id, int *mult, int *div)
130 {
131 	switch (id) {
132 	case KIRKWOOD_CPU_TO_L2:
133 	{
134 		u32 opt = SAR_KIRKWOOD_L2_RATIO(readl(sar));
135 		*mult = kirkwood_cpu_l2_ratios[opt][0];
136 		*div = kirkwood_cpu_l2_ratios[opt][1];
137 		break;
138 	}
139 	case KIRKWOOD_CPU_TO_DDR:
140 	{
141 		u32 opt = (readl(sar) >> SAR_KIRKWOOD_DDR_RATIO) &
142 			SAR_KIRKWOOD_DDR_RATIO_MASK;
143 		*mult = kirkwood_cpu_ddr_ratios[opt][0];
144 		*div = kirkwood_cpu_ddr_ratios[opt][1];
145 		break;
146 	}
147 	}
148 }
149 
150 static const u32 mv88f6180_cpu_freqs[] __initconst = {
151 	0, 0, 0, 0, 0,
152 	600000000,
153 	800000000,
154 	1000000000
155 };
156 
157 static u32 __init mv88f6180_get_cpu_freq(void __iomem *sar)
158 {
159 	u32 opt = (readl(sar) >> SAR_MV88F6180_CLK) & SAR_MV88F6180_CLK_MASK;
160 	return mv88f6180_cpu_freqs[opt];
161 }
162 
163 static const int mv88f6180_cpu_ddr_ratios[8][2] __initconst = {
164 	{ 0, 1 }, { 0, 1 }, { 0, 1 }, { 0, 1 },
165 	{ 0, 1 }, { 1, 3 }, { 1, 4 }, { 1, 5 }
166 };
167 
168 static void __init mv88f6180_get_clk_ratio(
169 	void __iomem *sar, int id, int *mult, int *div)
170 {
171 	switch (id) {
172 	case KIRKWOOD_CPU_TO_L2:
173 	{
174 		/* mv88f6180 has a fixed 1:2 CPU-to-L2 ratio */
175 		*mult = 1;
176 		*div = 2;
177 		break;
178 	}
179 	case KIRKWOOD_CPU_TO_DDR:
180 	{
181 		u32 opt = (readl(sar) >> SAR_MV88F6180_CLK) &
182 			SAR_MV88F6180_CLK_MASK;
183 		*mult = mv88f6180_cpu_ddr_ratios[opt][0];
184 		*div = mv88f6180_cpu_ddr_ratios[opt][1];
185 		break;
186 	}
187 	}
188 }
189 
190 static const struct coreclk_soc_desc kirkwood_coreclks = {
191 	.get_tclk_freq = kirkwood_get_tclk_freq,
192 	.get_cpu_freq = kirkwood_get_cpu_freq,
193 	.get_clk_ratio = kirkwood_get_clk_ratio,
194 	.ratios = kirkwood_coreclk_ratios,
195 	.num_ratios = ARRAY_SIZE(kirkwood_coreclk_ratios),
196 };
197 
198 static const struct coreclk_soc_desc mv88f6180_coreclks = {
199 	.get_tclk_freq = kirkwood_get_tclk_freq,
200 	.get_cpu_freq = mv88f6180_get_cpu_freq,
201 	.get_clk_ratio = mv88f6180_get_clk_ratio,
202 	.ratios = kirkwood_coreclk_ratios,
203 	.num_ratios = ARRAY_SIZE(kirkwood_coreclk_ratios),
204 };
205 
206 /*
207  * Clock Gating Control
208  */
209 
210 static const struct clk_gating_soc_desc kirkwood_gating_desc[] __initconst = {
211 	{ "ge0", NULL, 0, 0 },
212 	{ "pex0", NULL, 2, 0 },
213 	{ "usb0", NULL, 3, 0 },
214 	{ "sdio", NULL, 4, 0 },
215 	{ "tsu", NULL, 5, 0 },
216 	{ "runit", NULL, 7, 0 },
217 	{ "xor0", NULL, 8, 0 },
218 	{ "audio", NULL, 9, 0 },
219 	{ "sata0", NULL, 14, 0 },
220 	{ "sata1", NULL, 15, 0 },
221 	{ "xor1", NULL, 16, 0 },
222 	{ "crypto", NULL, 17, 0 },
223 	{ "pex1", NULL, 18, 0 },
224 	{ "ge1", NULL, 19, 0 },
225 	{ "tdm", NULL, 20, 0 },
226 	{ }
227 };
228 
229 
230 /*
231  * Clock Muxing Control
232  */
233 
234 struct clk_muxing_soc_desc {
235 	const char *name;
236 	const char **parents;
237 	int num_parents;
238 	int shift;
239 	int width;
240 	unsigned long flags;
241 };
242 
243 struct clk_muxing_ctrl {
244 	spinlock_t *lock;
245 	struct clk **muxes;
246 	int num_muxes;
247 };
248 
249 static const char *powersave_parents[] = {
250 	"cpuclk",
251 	"ddrclk",
252 };
253 
254 static const struct clk_muxing_soc_desc kirkwood_mux_desc[] __initconst = {
255 	{ "powersave", powersave_parents, ARRAY_SIZE(powersave_parents),
256 		11, 1, 0 },
257 };
258 
259 #define to_clk_mux(_hw) container_of(_hw, struct clk_mux, hw)
260 
261 static struct clk *clk_muxing_get_src(
262 	struct of_phandle_args *clkspec, void *data)
263 {
264 	struct clk_muxing_ctrl *ctrl = (struct clk_muxing_ctrl *)data;
265 	int n;
266 
267 	if (clkspec->args_count < 1)
268 		return ERR_PTR(-EINVAL);
269 
270 	for (n = 0; n < ctrl->num_muxes; n++) {
271 		struct clk_mux *mux =
272 			to_clk_mux(__clk_get_hw(ctrl->muxes[n]));
273 		if (clkspec->args[0] == mux->shift)
274 			return ctrl->muxes[n];
275 	}
276 	return ERR_PTR(-ENODEV);
277 }
278 
279 static void __init kirkwood_clk_muxing_setup(struct device_node *np,
280 				   const struct clk_muxing_soc_desc *desc)
281 {
282 	struct clk_muxing_ctrl *ctrl;
283 	void __iomem *base;
284 	int n;
285 
286 	base = of_iomap(np, 0);
287 	if (WARN_ON(!base))
288 		return;
289 
290 	ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL);
291 	if (WARN_ON(!ctrl))
292 		goto ctrl_out;
293 
294 	/* lock must already be initialized */
295 	ctrl->lock = &ctrl_gating_lock;
296 
297 	/* Count, allocate, and register clock muxes */
298 	for (n = 0; desc[n].name;)
299 		n++;
300 
301 	ctrl->num_muxes = n;
302 	ctrl->muxes = kcalloc(ctrl->num_muxes, sizeof(struct clk *),
303 			GFP_KERNEL);
304 	if (WARN_ON(!ctrl->muxes))
305 		goto muxes_out;
306 
307 	for (n = 0; n < ctrl->num_muxes; n++) {
308 		ctrl->muxes[n] = clk_register_mux(NULL, desc[n].name,
309 				desc[n].parents, desc[n].num_parents,
310 				desc[n].flags, base, desc[n].shift,
311 				desc[n].width, desc[n].flags, ctrl->lock);
312 		WARN_ON(IS_ERR(ctrl->muxes[n]));
313 	}
314 
315 	of_clk_add_provider(np, clk_muxing_get_src, ctrl);
316 
317 	return;
318 muxes_out:
319 	kfree(ctrl);
320 ctrl_out:
321 	iounmap(base);
322 }
323 
324 static void __init kirkwood_clk_init(struct device_node *np)
325 {
326 	struct device_node *cgnp =
327 		of_find_compatible_node(NULL, NULL, "marvell,kirkwood-gating-clock");
328 
329 
330 	if (of_device_is_compatible(np, "marvell,mv88f6180-core-clock"))
331 		mvebu_coreclk_setup(np, &mv88f6180_coreclks);
332 	else
333 		mvebu_coreclk_setup(np, &kirkwood_coreclks);
334 
335 	if (cgnp) {
336 		mvebu_clk_gating_setup(cgnp, kirkwood_gating_desc);
337 		kirkwood_clk_muxing_setup(cgnp, kirkwood_mux_desc);
338 	}
339 }
340 CLK_OF_DECLARE(kirkwood_clk, "marvell,kirkwood-core-clock",
341 	       kirkwood_clk_init);
342 CLK_OF_DECLARE(mv88f6180_clk, "marvell,mv88f6180-core-clock",
343 	       kirkwood_clk_init);
344