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14#include <linux/err.h>
15#include <linux/io.h>
16#include <linux/module.h>
17#include <linux/mod_devicetable.h>
18#include <linux/platform_device.h>
19#include <linux/ptp_clock_kernel.h>
20#include <linux/types.h>
21
22#define DTE_NCO_LOW_TIME_REG 0x00
23#define DTE_NCO_TIME_REG 0x04
24#define DTE_NCO_OVERFLOW_REG 0x08
25#define DTE_NCO_INC_REG 0x0c
26
27#define DTE_NCO_SUM2_MASK 0xffffffff
28#define DTE_NCO_SUM2_SHIFT 4ULL
29
30#define DTE_NCO_SUM3_MASK 0xff
31#define DTE_NCO_SUM3_SHIFT 36ULL
32#define DTE_NCO_SUM3_WR_SHIFT 8
33
34#define DTE_NCO_TS_WRAP_MASK 0xfff
35#define DTE_NCO_TS_WRAP_LSHIFT 32
36
37#define DTE_NCO_INC_DEFAULT 0x80000000
38#define DTE_NUM_REGS_TO_RESTORE 4
39
40
41#define DTE_WRAP_AROUND_NSEC_SHIFT 44
42
43
44#define DTE_NCO_MAX_NS 0xFFFFFFFFFFFLL
45
46
47#define DTE_PPB_ADJ(ppb) (u32)(div64_u64((((u64)abs(ppb) * BIT(28)) +\
48 62500000ULL), 125000000ULL))
49
50
51struct ptp_dte {
52 void __iomem *regs;
53 struct ptp_clock *ptp_clk;
54 struct ptp_clock_info caps;
55 struct device *dev;
56 u32 ts_ovf_last;
57 u32 ts_wrap_cnt;
58 spinlock_t lock;
59 u32 reg_val[DTE_NUM_REGS_TO_RESTORE];
60};
61
62static void dte_write_nco(void __iomem *regs, s64 ns)
63{
64 u32 sum2, sum3;
65
66 sum2 = (u32)((ns >> DTE_NCO_SUM2_SHIFT) & DTE_NCO_SUM2_MASK);
67
68 if (sum2 != DTE_NCO_SUM2_MASK)
69 sum2++;
70
71
72 sum3 = (u32)(((ns >> DTE_NCO_SUM3_SHIFT) & DTE_NCO_SUM3_MASK) <<
73 DTE_NCO_SUM3_WR_SHIFT);
74
75 writel(0, (regs + DTE_NCO_LOW_TIME_REG));
76 writel(sum2, (regs + DTE_NCO_TIME_REG));
77 writel(sum3, (regs + DTE_NCO_OVERFLOW_REG));
78}
79
80static s64 dte_read_nco(void __iomem *regs)
81{
82 u32 sum2, sum3;
83 s64 ns;
84
85
86
87
88
89 sum3 = readl(regs + DTE_NCO_OVERFLOW_REG) & DTE_NCO_SUM3_MASK;
90 sum2 = readl(regs + DTE_NCO_TIME_REG);
91 ns = ((s64)sum3 << DTE_NCO_SUM3_SHIFT) |
92 ((s64)sum2 << DTE_NCO_SUM2_SHIFT);
93
94 return ns;
95}
96
97static void dte_write_nco_delta(struct ptp_dte *ptp_dte, s64 delta)
98{
99 s64 ns;
100
101 ns = dte_read_nco(ptp_dte->regs);
102
103
104 if ((delta < 0) && (abs(delta) > ns)) {
105 if (ptp_dte->ts_wrap_cnt) {
106 ns += DTE_NCO_MAX_NS + delta;
107 ptp_dte->ts_wrap_cnt--;
108 } else {
109 ns = 0;
110 }
111 } else {
112 ns += delta;
113 if (ns > DTE_NCO_MAX_NS) {
114 ptp_dte->ts_wrap_cnt++;
115 ns -= DTE_NCO_MAX_NS;
116 }
117 }
118
119 dte_write_nco(ptp_dte->regs, ns);
120
121 ptp_dte->ts_ovf_last = (ns >> DTE_NCO_TS_WRAP_LSHIFT) &
122 DTE_NCO_TS_WRAP_MASK;
123}
124
125static s64 dte_read_nco_with_ovf(struct ptp_dte *ptp_dte)
126{
127 u32 ts_ovf;
128 s64 ns = 0;
129
130 ns = dte_read_nco(ptp_dte->regs);
131
132
133 ts_ovf = (ns >> DTE_NCO_TS_WRAP_LSHIFT) & DTE_NCO_TS_WRAP_MASK;
134
135
136 if (ts_ovf < ptp_dte->ts_ovf_last)
137 ptp_dte->ts_wrap_cnt++;
138
139 ptp_dte->ts_ovf_last = ts_ovf;
140
141
142 ns += (s64)(BIT_ULL(DTE_WRAP_AROUND_NSEC_SHIFT) * ptp_dte->ts_wrap_cnt);
143
144 return ns;
145}
146
147static int ptp_dte_adjfreq(struct ptp_clock_info *ptp, s32 ppb)
148{
149 u32 nco_incr;
150 unsigned long flags;
151 struct ptp_dte *ptp_dte = container_of(ptp, struct ptp_dte, caps);
152
153 if (abs(ppb) > ptp_dte->caps.max_adj) {
154 dev_err(ptp_dte->dev, "ppb adj too big\n");
155 return -EINVAL;
156 }
157
158 if (ppb < 0)
159 nco_incr = DTE_NCO_INC_DEFAULT - DTE_PPB_ADJ(ppb);
160 else
161 nco_incr = DTE_NCO_INC_DEFAULT + DTE_PPB_ADJ(ppb);
162
163 spin_lock_irqsave(&ptp_dte->lock, flags);
164 writel(nco_incr, ptp_dte->regs + DTE_NCO_INC_REG);
165 spin_unlock_irqrestore(&ptp_dte->lock, flags);
166
167 return 0;
168}
169
170static int ptp_dte_adjtime(struct ptp_clock_info *ptp, s64 delta)
171{
172 unsigned long flags;
173 struct ptp_dte *ptp_dte = container_of(ptp, struct ptp_dte, caps);
174
175 spin_lock_irqsave(&ptp_dte->lock, flags);
176 dte_write_nco_delta(ptp_dte, delta);
177 spin_unlock_irqrestore(&ptp_dte->lock, flags);
178
179 return 0;
180}
181
182static int ptp_dte_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts)
183{
184 unsigned long flags;
185 struct ptp_dte *ptp_dte = container_of(ptp, struct ptp_dte, caps);
186
187 spin_lock_irqsave(&ptp_dte->lock, flags);
188 *ts = ns_to_timespec64(dte_read_nco_with_ovf(ptp_dte));
189 spin_unlock_irqrestore(&ptp_dte->lock, flags);
190
191 return 0;
192}
193
194static int ptp_dte_settime(struct ptp_clock_info *ptp,
195 const struct timespec64 *ts)
196{
197 unsigned long flags;
198 struct ptp_dte *ptp_dte = container_of(ptp, struct ptp_dte, caps);
199
200 spin_lock_irqsave(&ptp_dte->lock, flags);
201
202
203 writel(0, ptp_dte->regs + DTE_NCO_INC_REG);
204
205 dte_write_nco(ptp_dte->regs, timespec64_to_ns(ts));
206
207
208 ptp_dte->ts_ovf_last = 0;
209 ptp_dte->ts_wrap_cnt = 0;
210
211
212 writel(DTE_NCO_INC_DEFAULT, ptp_dte->regs + DTE_NCO_INC_REG);
213
214 spin_unlock_irqrestore(&ptp_dte->lock, flags);
215
216 return 0;
217}
218
219static int ptp_dte_enable(struct ptp_clock_info *ptp,
220 struct ptp_clock_request *rq, int on)
221{
222 return -EOPNOTSUPP;
223}
224
225static const struct ptp_clock_info ptp_dte_caps = {
226 .owner = THIS_MODULE,
227 .name = "DTE PTP timer",
228 .max_adj = 50000000,
229 .n_ext_ts = 0,
230 .n_pins = 0,
231 .pps = 0,
232 .adjfreq = ptp_dte_adjfreq,
233 .adjtime = ptp_dte_adjtime,
234 .gettime64 = ptp_dte_gettime,
235 .settime64 = ptp_dte_settime,
236 .enable = ptp_dte_enable,
237};
238
239static int ptp_dte_probe(struct platform_device *pdev)
240{
241 struct ptp_dte *ptp_dte;
242 struct device *dev = &pdev->dev;
243 struct resource *res;
244
245 ptp_dte = devm_kzalloc(dev, sizeof(struct ptp_dte), GFP_KERNEL);
246 if (!ptp_dte)
247 return -ENOMEM;
248
249 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
250 ptp_dte->regs = devm_ioremap_resource(dev, res);
251 if (IS_ERR(ptp_dte->regs)) {
252 dev_err(dev,
253 "%s: io remap failed\n", __func__);
254 return PTR_ERR(ptp_dte->regs);
255 }
256
257 spin_lock_init(&ptp_dte->lock);
258
259 ptp_dte->dev = dev;
260 ptp_dte->caps = ptp_dte_caps;
261 ptp_dte->ptp_clk = ptp_clock_register(&ptp_dte->caps, &pdev->dev);
262 if (IS_ERR(ptp_dte->ptp_clk)) {
263 dev_err(dev,
264 "%s: Failed to register ptp clock\n", __func__);
265 return PTR_ERR(ptp_dte->ptp_clk);
266 }
267
268 platform_set_drvdata(pdev, ptp_dte);
269
270 dev_info(dev, "ptp clk probe done\n");
271
272 return 0;
273}
274
275static int ptp_dte_remove(struct platform_device *pdev)
276{
277 struct ptp_dte *ptp_dte = platform_get_drvdata(pdev);
278 u8 i;
279
280 ptp_clock_unregister(ptp_dte->ptp_clk);
281
282 for (i = 0; i < DTE_NUM_REGS_TO_RESTORE; i++)
283 writel(0, ptp_dte->regs + (i * sizeof(u32)));
284
285 return 0;
286}
287
288#ifdef CONFIG_PM_SLEEP
289static int ptp_dte_suspend(struct device *dev)
290{
291 struct ptp_dte *ptp_dte = dev_get_drvdata(dev);
292 u8 i;
293
294 for (i = 0; i < DTE_NUM_REGS_TO_RESTORE; i++) {
295 ptp_dte->reg_val[i] =
296 readl(ptp_dte->regs + (i * sizeof(u32)));
297 }
298
299
300 writel(0, ptp_dte->regs + DTE_NCO_INC_REG);
301
302 return 0;
303}
304
305static int ptp_dte_resume(struct device *dev)
306{
307 struct ptp_dte *ptp_dte = dev_get_drvdata(dev);
308 u8 i;
309
310 for (i = 0; i < DTE_NUM_REGS_TO_RESTORE; i++) {
311 if ((i * sizeof(u32)) != DTE_NCO_OVERFLOW_REG)
312 writel(ptp_dte->reg_val[i],
313 (ptp_dte->regs + (i * sizeof(u32))));
314 else
315 writel(((ptp_dte->reg_val[i] &
316 DTE_NCO_SUM3_MASK) << DTE_NCO_SUM3_WR_SHIFT),
317 (ptp_dte->regs + (i * sizeof(u32))));
318 }
319
320 return 0;
321}
322
323static const struct dev_pm_ops ptp_dte_pm_ops = {
324 .suspend = ptp_dte_suspend,
325 .resume = ptp_dte_resume
326};
327
328#define PTP_DTE_PM_OPS (&ptp_dte_pm_ops)
329#else
330#define PTP_DTE_PM_OPS NULL
331#endif
332
333static const struct of_device_id ptp_dte_of_match[] = {
334 { .compatible = "brcm,ptp-dte", },
335 {},
336};
337MODULE_DEVICE_TABLE(of, ptp_dte_of_match);
338
339static struct platform_driver ptp_dte_driver = {
340 .driver = {
341 .name = "ptp-dte",
342 .pm = PTP_DTE_PM_OPS,
343 .of_match_table = ptp_dte_of_match,
344 },
345 .probe = ptp_dte_probe,
346 .remove = ptp_dte_remove,
347};
348module_platform_driver(ptp_dte_driver);
349
350MODULE_AUTHOR("Broadcom");
351MODULE_DESCRIPTION("Broadcom DTE PTP Clock driver");
352MODULE_LICENSE("GPL v2");
353
