xref: /kernel/linux/linux-5.10/drivers/clk/at91/pmc.c (revision 8c2ecf20)
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 *  Copyright (C) 2013 Boris BREZILLON <b.brezillon@overkiz.com>
4 */
5
6#include <linux/clk-provider.h>
7#include <linux/clkdev.h>
8#include <linux/clk/at91_pmc.h>
9#include <linux/of.h>
10#include <linux/mfd/syscon.h>
11#include <linux/platform_device.h>
12#include <linux/regmap.h>
13#include <linux/syscore_ops.h>
14
15#include <asm/proc-fns.h>
16
17#include <dt-bindings/clock/at91.h>
18
19#include "pmc.h"
20
21#define PMC_MAX_IDS 128
22#define PMC_MAX_PCKS 8
23
24int of_at91_get_clk_range(struct device_node *np, const char *propname,
25			  struct clk_range *range)
26{
27	u32 min, max;
28	int ret;
29
30	ret = of_property_read_u32_index(np, propname, 0, &min);
31	if (ret)
32		return ret;
33
34	ret = of_property_read_u32_index(np, propname, 1, &max);
35	if (ret)
36		return ret;
37
38	if (range) {
39		range->min = min;
40		range->max = max;
41	}
42
43	return 0;
44}
45EXPORT_SYMBOL_GPL(of_at91_get_clk_range);
46
47struct clk_hw *of_clk_hw_pmc_get(struct of_phandle_args *clkspec, void *data)
48{
49	unsigned int type = clkspec->args[0];
50	unsigned int idx = clkspec->args[1];
51	struct pmc_data *pmc_data = data;
52
53	switch (type) {
54	case PMC_TYPE_CORE:
55		if (idx < pmc_data->ncore)
56			return pmc_data->chws[idx];
57		break;
58	case PMC_TYPE_SYSTEM:
59		if (idx < pmc_data->nsystem)
60			return pmc_data->shws[idx];
61		break;
62	case PMC_TYPE_PERIPHERAL:
63		if (idx < pmc_data->nperiph)
64			return pmc_data->phws[idx];
65		break;
66	case PMC_TYPE_GCK:
67		if (idx < pmc_data->ngck)
68			return pmc_data->ghws[idx];
69		break;
70	case PMC_TYPE_PROGRAMMABLE:
71		if (idx < pmc_data->npck)
72			return pmc_data->pchws[idx];
73		break;
74	default:
75		break;
76	}
77
78	pr_err("%s: invalid type (%u) or index (%u)\n", __func__, type, idx);
79
80	return ERR_PTR(-EINVAL);
81}
82
83struct pmc_data *pmc_data_allocate(unsigned int ncore, unsigned int nsystem,
84				   unsigned int nperiph, unsigned int ngck,
85				   unsigned int npck)
86{
87	unsigned int num_clks = ncore + nsystem + nperiph + ngck + npck;
88	struct pmc_data *pmc_data;
89
90	pmc_data = kzalloc(struct_size(pmc_data, hwtable, num_clks),
91			   GFP_KERNEL);
92	if (!pmc_data)
93		return NULL;
94
95	pmc_data->ncore = ncore;
96	pmc_data->chws = pmc_data->hwtable;
97
98	pmc_data->nsystem = nsystem;
99	pmc_data->shws = pmc_data->chws + ncore;
100
101	pmc_data->nperiph = nperiph;
102	pmc_data->phws = pmc_data->shws + nsystem;
103
104	pmc_data->ngck = ngck;
105	pmc_data->ghws = pmc_data->phws + nperiph;
106
107	pmc_data->npck = npck;
108	pmc_data->pchws = pmc_data->ghws + ngck;
109
110	return pmc_data;
111}
112
113#ifdef CONFIG_PM
114static struct regmap *pmcreg;
115
116static u8 registered_ids[PMC_MAX_IDS];
117static u8 registered_pcks[PMC_MAX_PCKS];
118
119static struct
120{
121	u32 scsr;
122	u32 pcsr0;
123	u32 uckr;
124	u32 mor;
125	u32 mcfr;
126	u32 pllar;
127	u32 mckr;
128	u32 usb;
129	u32 imr;
130	u32 pcsr1;
131	u32 pcr[PMC_MAX_IDS];
132	u32 audio_pll0;
133	u32 audio_pll1;
134	u32 pckr[PMC_MAX_PCKS];
135} pmc_cache;
136
137/*
138 * As Peripheral ID 0 is invalid on AT91 chips, the identifier is stored
139 * without alteration in the table, and 0 is for unused clocks.
140 */
141void pmc_register_id(u8 id)
142{
143	int i;
144
145	for (i = 0; i < PMC_MAX_IDS; i++) {
146		if (registered_ids[i] == 0) {
147			registered_ids[i] = id;
148			break;
149		}
150		if (registered_ids[i] == id)
151			break;
152	}
153}
154
155/*
156 * As Programmable Clock 0 is valid on AT91 chips, there is an offset
157 * of 1 between the stored value and the real clock ID.
158 */
159void pmc_register_pck(u8 pck)
160{
161	int i;
162
163	for (i = 0; i < PMC_MAX_PCKS; i++) {
164		if (registered_pcks[i] == 0) {
165			registered_pcks[i] = pck + 1;
166			break;
167		}
168		if (registered_pcks[i] == (pck + 1))
169			break;
170	}
171}
172
173static int pmc_suspend(void)
174{
175	int i;
176	u8 num;
177
178	regmap_read(pmcreg, AT91_PMC_SCSR, &pmc_cache.scsr);
179	regmap_read(pmcreg, AT91_PMC_PCSR, &pmc_cache.pcsr0);
180	regmap_read(pmcreg, AT91_CKGR_UCKR, &pmc_cache.uckr);
181	regmap_read(pmcreg, AT91_CKGR_MOR, &pmc_cache.mor);
182	regmap_read(pmcreg, AT91_CKGR_MCFR, &pmc_cache.mcfr);
183	regmap_read(pmcreg, AT91_CKGR_PLLAR, &pmc_cache.pllar);
184	regmap_read(pmcreg, AT91_PMC_MCKR, &pmc_cache.mckr);
185	regmap_read(pmcreg, AT91_PMC_USB, &pmc_cache.usb);
186	regmap_read(pmcreg, AT91_PMC_IMR, &pmc_cache.imr);
187	regmap_read(pmcreg, AT91_PMC_PCSR1, &pmc_cache.pcsr1);
188
189	for (i = 0; registered_ids[i]; i++) {
190		regmap_write(pmcreg, AT91_PMC_PCR,
191			     (registered_ids[i] & AT91_PMC_PCR_PID_MASK));
192		regmap_read(pmcreg, AT91_PMC_PCR,
193			    &pmc_cache.pcr[registered_ids[i]]);
194	}
195	for (i = 0; registered_pcks[i]; i++) {
196		num = registered_pcks[i] - 1;
197		regmap_read(pmcreg, AT91_PMC_PCKR(num), &pmc_cache.pckr[num]);
198	}
199
200	return 0;
201}
202
203static bool pmc_ready(unsigned int mask)
204{
205	unsigned int status;
206
207	regmap_read(pmcreg, AT91_PMC_SR, &status);
208
209	return ((status & mask) == mask) ? 1 : 0;
210}
211
212static void pmc_resume(void)
213{
214	int i;
215	u8 num;
216	u32 tmp;
217	u32 mask = AT91_PMC_MCKRDY | AT91_PMC_LOCKA;
218
219	regmap_read(pmcreg, AT91_PMC_MCKR, &tmp);
220	if (pmc_cache.mckr != tmp)
221		pr_warn("MCKR was not configured properly by the firmware\n");
222	regmap_read(pmcreg, AT91_CKGR_PLLAR, &tmp);
223	if (pmc_cache.pllar != tmp)
224		pr_warn("PLLAR was not configured properly by the firmware\n");
225
226	regmap_write(pmcreg, AT91_PMC_SCER, pmc_cache.scsr);
227	regmap_write(pmcreg, AT91_PMC_PCER, pmc_cache.pcsr0);
228	regmap_write(pmcreg, AT91_CKGR_UCKR, pmc_cache.uckr);
229	regmap_write(pmcreg, AT91_CKGR_MOR, pmc_cache.mor);
230	regmap_write(pmcreg, AT91_CKGR_MCFR, pmc_cache.mcfr);
231	regmap_write(pmcreg, AT91_PMC_USB, pmc_cache.usb);
232	regmap_write(pmcreg, AT91_PMC_IMR, pmc_cache.imr);
233	regmap_write(pmcreg, AT91_PMC_PCER1, pmc_cache.pcsr1);
234
235	for (i = 0; registered_ids[i]; i++) {
236		regmap_write(pmcreg, AT91_PMC_PCR,
237			     pmc_cache.pcr[registered_ids[i]] |
238			     AT91_PMC_PCR_CMD);
239	}
240	for (i = 0; registered_pcks[i]; i++) {
241		num = registered_pcks[i] - 1;
242		regmap_write(pmcreg, AT91_PMC_PCKR(num), pmc_cache.pckr[num]);
243	}
244
245	if (pmc_cache.uckr & AT91_PMC_UPLLEN)
246		mask |= AT91_PMC_LOCKU;
247
248	while (!pmc_ready(mask))
249		cpu_relax();
250}
251
252static struct syscore_ops pmc_syscore_ops = {
253	.suspend = pmc_suspend,
254	.resume = pmc_resume,
255};
256
257static const struct of_device_id sama5d2_pmc_dt_ids[] = {
258	{ .compatible = "atmel,sama5d2-pmc" },
259	{ /* sentinel */ }
260};
261
262static int __init pmc_register_ops(void)
263{
264	struct device_node *np;
265
266	np = of_find_matching_node(NULL, sama5d2_pmc_dt_ids);
267	if (!np)
268		return -ENODEV;
269
270	if (!of_device_is_available(np)) {
271		of_node_put(np);
272		return -ENODEV;
273	}
274
275	pmcreg = device_node_to_regmap(np);
276	of_node_put(np);
277	if (IS_ERR(pmcreg))
278		return PTR_ERR(pmcreg);
279
280	register_syscore_ops(&pmc_syscore_ops);
281
282	return 0;
283}
284/* This has to happen before arch_initcall because of the tcb_clksrc driver */
285postcore_initcall(pmc_register_ops);
286#endif
287