1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Tegra30 External Memory Controller driver
4 *
5 * Based on downstream driver from NVIDIA and tegra124-emc.c
6 * Copyright (C) 2011-2014 NVIDIA Corporation
7 *
8 * Author: Dmitry Osipenko <digetx@gmail.com>
9 * Copyright (C) 2019 GRATE-DRIVER project
10 */
11
12 #include <linux/bitfield.h>
13 #include <linux/clk.h>
14 #include <linux/clk/tegra.h>
15 #include <linux/debugfs.h>
16 #include <linux/delay.h>
17 #include <linux/err.h>
18 #include <linux/interconnect-provider.h>
19 #include <linux/interrupt.h>
20 #include <linux/io.h>
21 #include <linux/iopoll.h>
22 #include <linux/kernel.h>
23 #include <linux/module.h>
24 #include <linux/mutex.h>
25 #include <linux/of.h>
26 #include <linux/platform_device.h>
27 #include <linux/pm_opp.h>
28 #include <linux/slab.h>
29 #include <linux/sort.h>
30 #include <linux/types.h>
31
32 #include <soc/tegra/common.h>
33 #include <soc/tegra/fuse.h>
34
35 #include "../jedec_ddr.h"
36 #include "../of_memory.h"
37
38 #include "mc.h"
39
40 #define EMC_INTSTATUS 0x000
41 #define EMC_INTMASK 0x004
42 #define EMC_DBG 0x008
43 #define EMC_ADR_CFG 0x010
44 #define EMC_CFG 0x00c
45 #define EMC_REFCTRL 0x020
46 #define EMC_TIMING_CONTROL 0x028
47 #define EMC_RC 0x02c
48 #define EMC_RFC 0x030
49 #define EMC_RAS 0x034
50 #define EMC_RP 0x038
51 #define EMC_R2W 0x03c
52 #define EMC_W2R 0x040
53 #define EMC_R2P 0x044
54 #define EMC_W2P 0x048
55 #define EMC_RD_RCD 0x04c
56 #define EMC_WR_RCD 0x050
57 #define EMC_RRD 0x054
58 #define EMC_REXT 0x058
59 #define EMC_WDV 0x05c
60 #define EMC_QUSE 0x060
61 #define EMC_QRST 0x064
62 #define EMC_QSAFE 0x068
63 #define EMC_RDV 0x06c
64 #define EMC_REFRESH 0x070
65 #define EMC_BURST_REFRESH_NUM 0x074
66 #define EMC_PDEX2WR 0x078
67 #define EMC_PDEX2RD 0x07c
68 #define EMC_PCHG2PDEN 0x080
69 #define EMC_ACT2PDEN 0x084
70 #define EMC_AR2PDEN 0x088
71 #define EMC_RW2PDEN 0x08c
72 #define EMC_TXSR 0x090
73 #define EMC_TCKE 0x094
74 #define EMC_TFAW 0x098
75 #define EMC_TRPAB 0x09c
76 #define EMC_TCLKSTABLE 0x0a0
77 #define EMC_TCLKSTOP 0x0a4
78 #define EMC_TREFBW 0x0a8
79 #define EMC_QUSE_EXTRA 0x0ac
80 #define EMC_ODT_WRITE 0x0b0
81 #define EMC_ODT_READ 0x0b4
82 #define EMC_WEXT 0x0b8
83 #define EMC_CTT 0x0bc
84 #define EMC_MRS_WAIT_CNT 0x0c8
85 #define EMC_MRS 0x0cc
86 #define EMC_EMRS 0x0d0
87 #define EMC_SELF_REF 0x0e0
88 #define EMC_MRW 0x0e8
89 #define EMC_MRR 0x0ec
90 #define EMC_XM2DQSPADCTRL3 0x0f8
91 #define EMC_FBIO_SPARE 0x100
92 #define EMC_FBIO_CFG5 0x104
93 #define EMC_FBIO_CFG6 0x114
94 #define EMC_CFG_RSV 0x120
95 #define EMC_AUTO_CAL_CONFIG 0x2a4
96 #define EMC_AUTO_CAL_INTERVAL 0x2a8
97 #define EMC_AUTO_CAL_STATUS 0x2ac
98 #define EMC_STATUS 0x2b4
99 #define EMC_CFG_2 0x2b8
100 #define EMC_CFG_DIG_DLL 0x2bc
101 #define EMC_CFG_DIG_DLL_PERIOD 0x2c0
102 #define EMC_CTT_DURATION 0x2d8
103 #define EMC_CTT_TERM_CTRL 0x2dc
104 #define EMC_ZCAL_INTERVAL 0x2e0
105 #define EMC_ZCAL_WAIT_CNT 0x2e4
106 #define EMC_ZQ_CAL 0x2ec
107 #define EMC_XM2CMDPADCTRL 0x2f0
108 #define EMC_XM2DQSPADCTRL2 0x2fc
109 #define EMC_XM2DQPADCTRL2 0x304
110 #define EMC_XM2CLKPADCTRL 0x308
111 #define EMC_XM2COMPPADCTRL 0x30c
112 #define EMC_XM2VTTGENPADCTRL 0x310
113 #define EMC_XM2VTTGENPADCTRL2 0x314
114 #define EMC_XM2QUSEPADCTRL 0x318
115 #define EMC_DLL_XFORM_DQS0 0x328
116 #define EMC_DLL_XFORM_DQS1 0x32c
117 #define EMC_DLL_XFORM_DQS2 0x330
118 #define EMC_DLL_XFORM_DQS3 0x334
119 #define EMC_DLL_XFORM_DQS4 0x338
120 #define EMC_DLL_XFORM_DQS5 0x33c
121 #define EMC_DLL_XFORM_DQS6 0x340
122 #define EMC_DLL_XFORM_DQS7 0x344
123 #define EMC_DLL_XFORM_QUSE0 0x348
124 #define EMC_DLL_XFORM_QUSE1 0x34c
125 #define EMC_DLL_XFORM_QUSE2 0x350
126 #define EMC_DLL_XFORM_QUSE3 0x354
127 #define EMC_DLL_XFORM_QUSE4 0x358
128 #define EMC_DLL_XFORM_QUSE5 0x35c
129 #define EMC_DLL_XFORM_QUSE6 0x360
130 #define EMC_DLL_XFORM_QUSE7 0x364
131 #define EMC_DLL_XFORM_DQ0 0x368
132 #define EMC_DLL_XFORM_DQ1 0x36c
133 #define EMC_DLL_XFORM_DQ2 0x370
134 #define EMC_DLL_XFORM_DQ3 0x374
135 #define EMC_DLI_TRIM_TXDQS0 0x3a8
136 #define EMC_DLI_TRIM_TXDQS1 0x3ac
137 #define EMC_DLI_TRIM_TXDQS2 0x3b0
138 #define EMC_DLI_TRIM_TXDQS3 0x3b4
139 #define EMC_DLI_TRIM_TXDQS4 0x3b8
140 #define EMC_DLI_TRIM_TXDQS5 0x3bc
141 #define EMC_DLI_TRIM_TXDQS6 0x3c0
142 #define EMC_DLI_TRIM_TXDQS7 0x3c4
143 #define EMC_STALL_THEN_EXE_BEFORE_CLKCHANGE 0x3c8
144 #define EMC_STALL_THEN_EXE_AFTER_CLKCHANGE 0x3cc
145 #define EMC_UNSTALL_RW_AFTER_CLKCHANGE 0x3d0
146 #define EMC_SEL_DPD_CTRL 0x3d8
147 #define EMC_PRE_REFRESH_REQ_CNT 0x3dc
148 #define EMC_DYN_SELF_REF_CONTROL 0x3e0
149 #define EMC_TXSRDLL 0x3e4
150
151 #define EMC_STATUS_TIMING_UPDATE_STALLED BIT(23)
152
153 #define EMC_MODE_SET_DLL_RESET BIT(8)
154 #define EMC_MODE_SET_LONG_CNT BIT(26)
155
156 #define EMC_SELF_REF_CMD_ENABLED BIT(0)
157
158 #define DRAM_DEV_SEL_ALL (0 << 30)
159 #define DRAM_DEV_SEL_0 BIT(31)
160 #define DRAM_DEV_SEL_1 BIT(30)
161 #define DRAM_BROADCAST(num) \
162 ((num) > 1 ? DRAM_DEV_SEL_ALL : DRAM_DEV_SEL_0)
163
164 #define EMC_ZQ_CAL_CMD BIT(0)
165 #define EMC_ZQ_CAL_LONG BIT(4)
166 #define EMC_ZQ_CAL_LONG_CMD_DEV0 \
167 (DRAM_DEV_SEL_0 | EMC_ZQ_CAL_LONG | EMC_ZQ_CAL_CMD)
168 #define EMC_ZQ_CAL_LONG_CMD_DEV1 \
169 (DRAM_DEV_SEL_1 | EMC_ZQ_CAL_LONG | EMC_ZQ_CAL_CMD)
170
171 #define EMC_DBG_READ_MUX_ASSEMBLY BIT(0)
172 #define EMC_DBG_WRITE_MUX_ACTIVE BIT(1)
173 #define EMC_DBG_FORCE_UPDATE BIT(2)
174 #define EMC_DBG_CFG_PRIORITY BIT(24)
175
176 #define EMC_CFG5_QUSE_MODE_SHIFT 13
177 #define EMC_CFG5_QUSE_MODE_MASK (7 << EMC_CFG5_QUSE_MODE_SHIFT)
178
179 #define EMC_CFG5_QUSE_MODE_INTERNAL_LPBK 2
180 #define EMC_CFG5_QUSE_MODE_PULSE_INTERN 3
181
182 #define EMC_SEL_DPD_CTRL_QUSE_DPD_ENABLE BIT(9)
183
184 #define EMC_XM2COMPPADCTRL_VREF_CAL_ENABLE BIT(10)
185
186 #define EMC_XM2QUSEPADCTRL_IVREF_ENABLE BIT(4)
187
188 #define EMC_XM2DQSPADCTRL2_VREF_ENABLE BIT(5)
189 #define EMC_XM2DQSPADCTRL3_VREF_ENABLE BIT(5)
190
191 #define EMC_AUTO_CAL_STATUS_ACTIVE BIT(31)
192
193 #define EMC_FBIO_CFG5_DRAM_TYPE_MASK 0x3
194
195 #define EMC_MRS_WAIT_CNT_SHORT_WAIT_MASK 0x3ff
196 #define EMC_MRS_WAIT_CNT_LONG_WAIT_SHIFT 16
197 #define EMC_MRS_WAIT_CNT_LONG_WAIT_MASK \
198 (0x3ff << EMC_MRS_WAIT_CNT_LONG_WAIT_SHIFT)
199
200 #define EMC_REFCTRL_DEV_SEL_MASK 0x3
201 #define EMC_REFCTRL_ENABLE BIT(31)
202 #define EMC_REFCTRL_ENABLE_ALL(num) \
203 (((num) > 1 ? 0 : 2) | EMC_REFCTRL_ENABLE)
204 #define EMC_REFCTRL_DISABLE_ALL(num) ((num) > 1 ? 0 : 2)
205
206 #define EMC_CFG_PERIODIC_QRST BIT(21)
207 #define EMC_CFG_DYN_SREF_ENABLE BIT(28)
208
209 #define EMC_CLKCHANGE_REQ_ENABLE BIT(0)
210 #define EMC_CLKCHANGE_PD_ENABLE BIT(1)
211 #define EMC_CLKCHANGE_SR_ENABLE BIT(2)
212
213 #define EMC_TIMING_UPDATE BIT(0)
214
215 #define EMC_REFRESH_OVERFLOW_INT BIT(3)
216 #define EMC_CLKCHANGE_COMPLETE_INT BIT(4)
217 #define EMC_MRR_DIVLD_INT BIT(5)
218
219 #define EMC_MRR_DEV_SELECTN GENMASK(31, 30)
220 #define EMC_MRR_MRR_MA GENMASK(23, 16)
221 #define EMC_MRR_MRR_DATA GENMASK(15, 0)
222
223 #define EMC_ADR_CFG_EMEM_NUMDEV BIT(0)
224
225 enum emc_dram_type {
226 DRAM_TYPE_DDR3,
227 DRAM_TYPE_DDR1,
228 DRAM_TYPE_LPDDR2,
229 DRAM_TYPE_DDR2,
230 };
231
232 enum emc_dll_change {
233 DLL_CHANGE_NONE,
234 DLL_CHANGE_ON,
235 DLL_CHANGE_OFF
236 };
237
238 static const u16 emc_timing_registers[] = {
239 [0] = EMC_RC,
240 [1] = EMC_RFC,
241 [2] = EMC_RAS,
242 [3] = EMC_RP,
243 [4] = EMC_R2W,
244 [5] = EMC_W2R,
245 [6] = EMC_R2P,
246 [7] = EMC_W2P,
247 [8] = EMC_RD_RCD,
248 [9] = EMC_WR_RCD,
249 [10] = EMC_RRD,
250 [11] = EMC_REXT,
251 [12] = EMC_WEXT,
252 [13] = EMC_WDV,
253 [14] = EMC_QUSE,
254 [15] = EMC_QRST,
255 [16] = EMC_QSAFE,
256 [17] = EMC_RDV,
257 [18] = EMC_REFRESH,
258 [19] = EMC_BURST_REFRESH_NUM,
259 [20] = EMC_PRE_REFRESH_REQ_CNT,
260 [21] = EMC_PDEX2WR,
261 [22] = EMC_PDEX2RD,
262 [23] = EMC_PCHG2PDEN,
263 [24] = EMC_ACT2PDEN,
264 [25] = EMC_AR2PDEN,
265 [26] = EMC_RW2PDEN,
266 [27] = EMC_TXSR,
267 [28] = EMC_TXSRDLL,
268 [29] = EMC_TCKE,
269 [30] = EMC_TFAW,
270 [31] = EMC_TRPAB,
271 [32] = EMC_TCLKSTABLE,
272 [33] = EMC_TCLKSTOP,
273 [34] = EMC_TREFBW,
274 [35] = EMC_QUSE_EXTRA,
275 [36] = EMC_FBIO_CFG6,
276 [37] = EMC_ODT_WRITE,
277 [38] = EMC_ODT_READ,
278 [39] = EMC_FBIO_CFG5,
279 [40] = EMC_CFG_DIG_DLL,
280 [41] = EMC_CFG_DIG_DLL_PERIOD,
281 [42] = EMC_DLL_XFORM_DQS0,
282 [43] = EMC_DLL_XFORM_DQS1,
283 [44] = EMC_DLL_XFORM_DQS2,
284 [45] = EMC_DLL_XFORM_DQS3,
285 [46] = EMC_DLL_XFORM_DQS4,
286 [47] = EMC_DLL_XFORM_DQS5,
287 [48] = EMC_DLL_XFORM_DQS6,
288 [49] = EMC_DLL_XFORM_DQS7,
289 [50] = EMC_DLL_XFORM_QUSE0,
290 [51] = EMC_DLL_XFORM_QUSE1,
291 [52] = EMC_DLL_XFORM_QUSE2,
292 [53] = EMC_DLL_XFORM_QUSE3,
293 [54] = EMC_DLL_XFORM_QUSE4,
294 [55] = EMC_DLL_XFORM_QUSE5,
295 [56] = EMC_DLL_XFORM_QUSE6,
296 [57] = EMC_DLL_XFORM_QUSE7,
297 [58] = EMC_DLI_TRIM_TXDQS0,
298 [59] = EMC_DLI_TRIM_TXDQS1,
299 [60] = EMC_DLI_TRIM_TXDQS2,
300 [61] = EMC_DLI_TRIM_TXDQS3,
301 [62] = EMC_DLI_TRIM_TXDQS4,
302 [63] = EMC_DLI_TRIM_TXDQS5,
303 [64] = EMC_DLI_TRIM_TXDQS6,
304 [65] = EMC_DLI_TRIM_TXDQS7,
305 [66] = EMC_DLL_XFORM_DQ0,
306 [67] = EMC_DLL_XFORM_DQ1,
307 [68] = EMC_DLL_XFORM_DQ2,
308 [69] = EMC_DLL_XFORM_DQ3,
309 [70] = EMC_XM2CMDPADCTRL,
310 [71] = EMC_XM2DQSPADCTRL2,
311 [72] = EMC_XM2DQPADCTRL2,
312 [73] = EMC_XM2CLKPADCTRL,
313 [74] = EMC_XM2COMPPADCTRL,
314 [75] = EMC_XM2VTTGENPADCTRL,
315 [76] = EMC_XM2VTTGENPADCTRL2,
316 [77] = EMC_XM2QUSEPADCTRL,
317 [78] = EMC_XM2DQSPADCTRL3,
318 [79] = EMC_CTT_TERM_CTRL,
319 [80] = EMC_ZCAL_INTERVAL,
320 [81] = EMC_ZCAL_WAIT_CNT,
321 [82] = EMC_MRS_WAIT_CNT,
322 [83] = EMC_AUTO_CAL_CONFIG,
323 [84] = EMC_CTT,
324 [85] = EMC_CTT_DURATION,
325 [86] = EMC_DYN_SELF_REF_CONTROL,
326 [87] = EMC_FBIO_SPARE,
327 [88] = EMC_CFG_RSV,
328 };
329
330 struct emc_timing {
331 unsigned long rate;
332
333 u32 data[ARRAY_SIZE(emc_timing_registers)];
334
335 u32 emc_auto_cal_interval;
336 u32 emc_mode_1;
337 u32 emc_mode_2;
338 u32 emc_mode_reset;
339 u32 emc_zcal_cnt_long;
340 bool emc_cfg_periodic_qrst;
341 bool emc_cfg_dyn_self_ref;
342 };
343
344 enum emc_rate_request_type {
345 EMC_RATE_DEBUG,
346 EMC_RATE_ICC,
347 EMC_RATE_TYPE_MAX,
348 };
349
350 struct emc_rate_request {
351 unsigned long min_rate;
352 unsigned long max_rate;
353 };
354
355 struct tegra_emc {
356 struct device *dev;
357 struct tegra_mc *mc;
358 struct icc_provider provider;
359 struct notifier_block clk_nb;
360 struct clk *clk;
361 void __iomem *regs;
362 unsigned int irq;
363 bool bad_state;
364
365 struct emc_timing *new_timing;
366 struct emc_timing *timings;
367 unsigned int num_timings;
368
369 u32 mc_override;
370 u32 emc_cfg;
371
372 u32 emc_mode_1;
373 u32 emc_mode_2;
374 u32 emc_mode_reset;
375
376 bool vref_cal_toggle : 1;
377 bool zcal_long : 1;
378 bool dll_on : 1;
379
380 struct {
381 struct dentry *root;
382 unsigned long min_rate;
383 unsigned long max_rate;
384 } debugfs;
385
386 /*
387 * There are multiple sources in the EMC driver which could request
388 * a min/max clock rate, these rates are contained in this array.
389 */
390 struct emc_rate_request requested_rate[EMC_RATE_TYPE_MAX];
391
392 /* protect shared rate-change code path */
393 struct mutex rate_lock;
394
395 bool mrr_error;
396 };
397
emc_seq_update_timing(struct tegra_emc * emc)398 static int emc_seq_update_timing(struct tegra_emc *emc)
399 {
400 u32 val;
401 int err;
402
403 writel_relaxed(EMC_TIMING_UPDATE, emc->regs + EMC_TIMING_CONTROL);
404
405 err = readl_relaxed_poll_timeout_atomic(emc->regs + EMC_STATUS, val,
406 !(val & EMC_STATUS_TIMING_UPDATE_STALLED),
407 1, 200);
408 if (err) {
409 dev_err(emc->dev, "failed to update timing: %d\n", err);
410 return err;
411 }
412
413 return 0;
414 }
415
tegra_emc_isr(int irq,void * data)416 static irqreturn_t tegra_emc_isr(int irq, void *data)
417 {
418 struct tegra_emc *emc = data;
419 u32 intmask = EMC_REFRESH_OVERFLOW_INT;
420 u32 status;
421
422 status = readl_relaxed(emc->regs + EMC_INTSTATUS) & intmask;
423 if (!status)
424 return IRQ_NONE;
425
426 /* notify about HW problem */
427 if (status & EMC_REFRESH_OVERFLOW_INT)
428 dev_err_ratelimited(emc->dev,
429 "refresh request overflow timeout\n");
430
431 /* clear interrupts */
432 writel_relaxed(status, emc->regs + EMC_INTSTATUS);
433
434 return IRQ_HANDLED;
435 }
436
emc_find_timing(struct tegra_emc * emc,unsigned long rate)437 static struct emc_timing *emc_find_timing(struct tegra_emc *emc,
438 unsigned long rate)
439 {
440 struct emc_timing *timing = NULL;
441 unsigned int i;
442
443 for (i = 0; i < emc->num_timings; i++) {
444 if (emc->timings[i].rate >= rate) {
445 timing = &emc->timings[i];
446 break;
447 }
448 }
449
450 if (!timing) {
451 dev_err(emc->dev, "no timing for rate %lu\n", rate);
452 return NULL;
453 }
454
455 return timing;
456 }
457
emc_dqs_preset(struct tegra_emc * emc,struct emc_timing * timing,bool * schmitt_to_vref)458 static bool emc_dqs_preset(struct tegra_emc *emc, struct emc_timing *timing,
459 bool *schmitt_to_vref)
460 {
461 bool preset = false;
462 u32 val;
463
464 if (timing->data[71] & EMC_XM2DQSPADCTRL2_VREF_ENABLE) {
465 val = readl_relaxed(emc->regs + EMC_XM2DQSPADCTRL2);
466
467 if (!(val & EMC_XM2DQSPADCTRL2_VREF_ENABLE)) {
468 val |= EMC_XM2DQSPADCTRL2_VREF_ENABLE;
469 writel_relaxed(val, emc->regs + EMC_XM2DQSPADCTRL2);
470
471 preset = true;
472 }
473 }
474
475 if (timing->data[78] & EMC_XM2DQSPADCTRL3_VREF_ENABLE) {
476 val = readl_relaxed(emc->regs + EMC_XM2DQSPADCTRL3);
477
478 if (!(val & EMC_XM2DQSPADCTRL3_VREF_ENABLE)) {
479 val |= EMC_XM2DQSPADCTRL3_VREF_ENABLE;
480 writel_relaxed(val, emc->regs + EMC_XM2DQSPADCTRL3);
481
482 preset = true;
483 }
484 }
485
486 if (timing->data[77] & EMC_XM2QUSEPADCTRL_IVREF_ENABLE) {
487 val = readl_relaxed(emc->regs + EMC_XM2QUSEPADCTRL);
488
489 if (!(val & EMC_XM2QUSEPADCTRL_IVREF_ENABLE)) {
490 val |= EMC_XM2QUSEPADCTRL_IVREF_ENABLE;
491 writel_relaxed(val, emc->regs + EMC_XM2QUSEPADCTRL);
492
493 *schmitt_to_vref = true;
494 preset = true;
495 }
496 }
497
498 return preset;
499 }
500
emc_prepare_mc_clk_cfg(struct tegra_emc * emc,unsigned long rate)501 static int emc_prepare_mc_clk_cfg(struct tegra_emc *emc, unsigned long rate)
502 {
503 struct tegra_mc *mc = emc->mc;
504 unsigned int misc0_index = 16;
505 unsigned int i;
506 bool same;
507
508 for (i = 0; i < mc->num_timings; i++) {
509 if (mc->timings[i].rate != rate)
510 continue;
511
512 if (mc->timings[i].emem_data[misc0_index] & BIT(27))
513 same = true;
514 else
515 same = false;
516
517 return tegra20_clk_prepare_emc_mc_same_freq(emc->clk, same);
518 }
519
520 return -EINVAL;
521 }
522
emc_prepare_timing_change(struct tegra_emc * emc,unsigned long rate)523 static int emc_prepare_timing_change(struct tegra_emc *emc, unsigned long rate)
524 {
525 struct emc_timing *timing = emc_find_timing(emc, rate);
526 enum emc_dll_change dll_change;
527 enum emc_dram_type dram_type;
528 bool schmitt_to_vref = false;
529 unsigned int pre_wait = 0;
530 bool qrst_used = false;
531 unsigned int dram_num;
532 unsigned int i;
533 u32 fbio_cfg5;
534 u32 emc_dbg;
535 u32 val;
536 int err;
537
538 if (!timing || emc->bad_state)
539 return -EINVAL;
540
541 dev_dbg(emc->dev, "%s: using timing rate %lu for requested rate %lu\n",
542 __func__, timing->rate, rate);
543
544 emc->bad_state = true;
545
546 err = emc_prepare_mc_clk_cfg(emc, rate);
547 if (err) {
548 dev_err(emc->dev, "mc clock preparation failed: %d\n", err);
549 return err;
550 }
551
552 emc->vref_cal_toggle = false;
553 emc->mc_override = mc_readl(emc->mc, MC_EMEM_ARB_OVERRIDE);
554 emc->emc_cfg = readl_relaxed(emc->regs + EMC_CFG);
555 emc_dbg = readl_relaxed(emc->regs + EMC_DBG);
556
557 if (emc->dll_on == !!(timing->emc_mode_1 & 0x1))
558 dll_change = DLL_CHANGE_NONE;
559 else if (timing->emc_mode_1 & 0x1)
560 dll_change = DLL_CHANGE_ON;
561 else
562 dll_change = DLL_CHANGE_OFF;
563
564 emc->dll_on = !!(timing->emc_mode_1 & 0x1);
565
566 if (timing->data[80] && !readl_relaxed(emc->regs + EMC_ZCAL_INTERVAL))
567 emc->zcal_long = true;
568 else
569 emc->zcal_long = false;
570
571 fbio_cfg5 = readl_relaxed(emc->regs + EMC_FBIO_CFG5);
572 dram_type = fbio_cfg5 & EMC_FBIO_CFG5_DRAM_TYPE_MASK;
573
574 dram_num = tegra_mc_get_emem_device_count(emc->mc);
575
576 /* disable dynamic self-refresh */
577 if (emc->emc_cfg & EMC_CFG_DYN_SREF_ENABLE) {
578 emc->emc_cfg &= ~EMC_CFG_DYN_SREF_ENABLE;
579 writel_relaxed(emc->emc_cfg, emc->regs + EMC_CFG);
580
581 pre_wait = 5;
582 }
583
584 /* update MC arbiter settings */
585 val = mc_readl(emc->mc, MC_EMEM_ARB_OUTSTANDING_REQ);
586 if (!(val & MC_EMEM_ARB_OUTSTANDING_REQ_HOLDOFF_OVERRIDE) ||
587 ((val & MC_EMEM_ARB_OUTSTANDING_REQ_MAX_MASK) > 0x50)) {
588
589 val = MC_EMEM_ARB_OUTSTANDING_REQ_LIMIT_ENABLE |
590 MC_EMEM_ARB_OUTSTANDING_REQ_HOLDOFF_OVERRIDE | 0x50;
591 mc_writel(emc->mc, val, MC_EMEM_ARB_OUTSTANDING_REQ);
592 mc_writel(emc->mc, MC_TIMING_UPDATE, MC_TIMING_CONTROL);
593 }
594
595 if (emc->mc_override & MC_EMEM_ARB_OVERRIDE_EACK_MASK)
596 mc_writel(emc->mc,
597 emc->mc_override & ~MC_EMEM_ARB_OVERRIDE_EACK_MASK,
598 MC_EMEM_ARB_OVERRIDE);
599
600 /* check DQ/DQS VREF delay */
601 if (emc_dqs_preset(emc, timing, &schmitt_to_vref)) {
602 if (pre_wait < 3)
603 pre_wait = 3;
604 }
605
606 if (pre_wait) {
607 err = emc_seq_update_timing(emc);
608 if (err)
609 return err;
610
611 udelay(pre_wait);
612 }
613
614 /* disable auto-calibration if VREF mode is switching */
615 if (timing->emc_auto_cal_interval) {
616 val = readl_relaxed(emc->regs + EMC_XM2COMPPADCTRL);
617 val ^= timing->data[74];
618
619 if (val & EMC_XM2COMPPADCTRL_VREF_CAL_ENABLE) {
620 writel_relaxed(0, emc->regs + EMC_AUTO_CAL_INTERVAL);
621
622 err = readl_relaxed_poll_timeout_atomic(
623 emc->regs + EMC_AUTO_CAL_STATUS, val,
624 !(val & EMC_AUTO_CAL_STATUS_ACTIVE), 1, 300);
625 if (err) {
626 dev_err(emc->dev,
627 "auto-cal finish timeout: %d\n", err);
628 return err;
629 }
630
631 emc->vref_cal_toggle = true;
632 }
633 }
634
635 /* program shadow registers */
636 for (i = 0; i < ARRAY_SIZE(timing->data); i++) {
637 /* EMC_XM2CLKPADCTRL should be programmed separately */
638 if (i != 73)
639 writel_relaxed(timing->data[i],
640 emc->regs + emc_timing_registers[i]);
641 }
642
643 err = tegra_mc_write_emem_configuration(emc->mc, timing->rate);
644 if (err)
645 return err;
646
647 /* DDR3: predict MRS long wait count */
648 if (dram_type == DRAM_TYPE_DDR3 && dll_change == DLL_CHANGE_ON) {
649 u32 cnt = 512;
650
651 if (emc->zcal_long)
652 cnt -= dram_num * 256;
653
654 val = timing->data[82] & EMC_MRS_WAIT_CNT_SHORT_WAIT_MASK;
655 if (cnt < val)
656 cnt = val;
657
658 val = timing->data[82] & ~EMC_MRS_WAIT_CNT_LONG_WAIT_MASK;
659 val |= (cnt << EMC_MRS_WAIT_CNT_LONG_WAIT_SHIFT) &
660 EMC_MRS_WAIT_CNT_LONG_WAIT_MASK;
661
662 writel_relaxed(val, emc->regs + EMC_MRS_WAIT_CNT);
663 }
664
665 /* this read also completes the writes */
666 val = readl_relaxed(emc->regs + EMC_SEL_DPD_CTRL);
667
668 if (!(val & EMC_SEL_DPD_CTRL_QUSE_DPD_ENABLE) && schmitt_to_vref) {
669 u32 cur_mode, new_mode;
670
671 cur_mode = fbio_cfg5 & EMC_CFG5_QUSE_MODE_MASK;
672 cur_mode >>= EMC_CFG5_QUSE_MODE_SHIFT;
673
674 new_mode = timing->data[39] & EMC_CFG5_QUSE_MODE_MASK;
675 new_mode >>= EMC_CFG5_QUSE_MODE_SHIFT;
676
677 if ((cur_mode != EMC_CFG5_QUSE_MODE_PULSE_INTERN &&
678 cur_mode != EMC_CFG5_QUSE_MODE_INTERNAL_LPBK) ||
679 (new_mode != EMC_CFG5_QUSE_MODE_PULSE_INTERN &&
680 new_mode != EMC_CFG5_QUSE_MODE_INTERNAL_LPBK))
681 qrst_used = true;
682 }
683
684 /* flow control marker 1 */
685 writel_relaxed(0x1, emc->regs + EMC_STALL_THEN_EXE_BEFORE_CLKCHANGE);
686
687 /* enable periodic reset */
688 if (qrst_used) {
689 writel_relaxed(emc_dbg | EMC_DBG_WRITE_MUX_ACTIVE,
690 emc->regs + EMC_DBG);
691 writel_relaxed(emc->emc_cfg | EMC_CFG_PERIODIC_QRST,
692 emc->regs + EMC_CFG);
693 writel_relaxed(emc_dbg, emc->regs + EMC_DBG);
694 }
695
696 /* disable auto-refresh to save time after clock change */
697 writel_relaxed(EMC_REFCTRL_DISABLE_ALL(dram_num),
698 emc->regs + EMC_REFCTRL);
699
700 /* turn off DLL and enter self-refresh on DDR3 */
701 if (dram_type == DRAM_TYPE_DDR3) {
702 if (dll_change == DLL_CHANGE_OFF)
703 writel_relaxed(timing->emc_mode_1,
704 emc->regs + EMC_EMRS);
705
706 writel_relaxed(DRAM_BROADCAST(dram_num) |
707 EMC_SELF_REF_CMD_ENABLED,
708 emc->regs + EMC_SELF_REF);
709 }
710
711 /* flow control marker 2 */
712 writel_relaxed(0x1, emc->regs + EMC_STALL_THEN_EXE_AFTER_CLKCHANGE);
713
714 /* enable write-active MUX, update unshadowed pad control */
715 writel_relaxed(emc_dbg | EMC_DBG_WRITE_MUX_ACTIVE, emc->regs + EMC_DBG);
716 writel_relaxed(timing->data[73], emc->regs + EMC_XM2CLKPADCTRL);
717
718 /* restore periodic QRST and disable write-active MUX */
719 val = !!(emc->emc_cfg & EMC_CFG_PERIODIC_QRST);
720 if (qrst_used || timing->emc_cfg_periodic_qrst != val) {
721 if (timing->emc_cfg_periodic_qrst)
722 emc->emc_cfg |= EMC_CFG_PERIODIC_QRST;
723 else
724 emc->emc_cfg &= ~EMC_CFG_PERIODIC_QRST;
725
726 writel_relaxed(emc->emc_cfg, emc->regs + EMC_CFG);
727 }
728 writel_relaxed(emc_dbg, emc->regs + EMC_DBG);
729
730 /* exit self-refresh on DDR3 */
731 if (dram_type == DRAM_TYPE_DDR3)
732 writel_relaxed(DRAM_BROADCAST(dram_num),
733 emc->regs + EMC_SELF_REF);
734
735 /* set DRAM-mode registers */
736 if (dram_type == DRAM_TYPE_DDR3) {
737 if (timing->emc_mode_1 != emc->emc_mode_1)
738 writel_relaxed(timing->emc_mode_1,
739 emc->regs + EMC_EMRS);
740
741 if (timing->emc_mode_2 != emc->emc_mode_2)
742 writel_relaxed(timing->emc_mode_2,
743 emc->regs + EMC_EMRS);
744
745 if (timing->emc_mode_reset != emc->emc_mode_reset ||
746 dll_change == DLL_CHANGE_ON) {
747 val = timing->emc_mode_reset;
748 if (dll_change == DLL_CHANGE_ON) {
749 val |= EMC_MODE_SET_DLL_RESET;
750 val |= EMC_MODE_SET_LONG_CNT;
751 } else {
752 val &= ~EMC_MODE_SET_DLL_RESET;
753 }
754 writel_relaxed(val, emc->regs + EMC_MRS);
755 }
756 } else {
757 if (timing->emc_mode_2 != emc->emc_mode_2)
758 writel_relaxed(timing->emc_mode_2,
759 emc->regs + EMC_MRW);
760
761 if (timing->emc_mode_1 != emc->emc_mode_1)
762 writel_relaxed(timing->emc_mode_1,
763 emc->regs + EMC_MRW);
764 }
765
766 emc->emc_mode_1 = timing->emc_mode_1;
767 emc->emc_mode_2 = timing->emc_mode_2;
768 emc->emc_mode_reset = timing->emc_mode_reset;
769
770 /* issue ZCAL command if turning ZCAL on */
771 if (emc->zcal_long) {
772 writel_relaxed(EMC_ZQ_CAL_LONG_CMD_DEV0,
773 emc->regs + EMC_ZQ_CAL);
774
775 if (dram_num > 1)
776 writel_relaxed(EMC_ZQ_CAL_LONG_CMD_DEV1,
777 emc->regs + EMC_ZQ_CAL);
778 }
779
780 /* flow control marker 3 */
781 writel_relaxed(0x1, emc->regs + EMC_UNSTALL_RW_AFTER_CLKCHANGE);
782
783 /*
784 * Read and discard an arbitrary MC register (Note: EMC registers
785 * can't be used) to ensure the register writes are completed.
786 */
787 mc_readl(emc->mc, MC_EMEM_ARB_OVERRIDE);
788
789 return 0;
790 }
791
emc_complete_timing_change(struct tegra_emc * emc,unsigned long rate)792 static int emc_complete_timing_change(struct tegra_emc *emc,
793 unsigned long rate)
794 {
795 struct emc_timing *timing = emc_find_timing(emc, rate);
796 unsigned int dram_num;
797 int err;
798 u32 v;
799
800 err = readl_relaxed_poll_timeout_atomic(emc->regs + EMC_INTSTATUS, v,
801 v & EMC_CLKCHANGE_COMPLETE_INT,
802 1, 100);
803 if (err) {
804 dev_err(emc->dev, "emc-car handshake timeout: %d\n", err);
805 return err;
806 }
807
808 /* re-enable auto-refresh */
809 dram_num = tegra_mc_get_emem_device_count(emc->mc);
810 writel_relaxed(EMC_REFCTRL_ENABLE_ALL(dram_num),
811 emc->regs + EMC_REFCTRL);
812
813 /* restore auto-calibration */
814 if (emc->vref_cal_toggle)
815 writel_relaxed(timing->emc_auto_cal_interval,
816 emc->regs + EMC_AUTO_CAL_INTERVAL);
817
818 /* restore dynamic self-refresh */
819 if (timing->emc_cfg_dyn_self_ref) {
820 emc->emc_cfg |= EMC_CFG_DYN_SREF_ENABLE;
821 writel_relaxed(emc->emc_cfg, emc->regs + EMC_CFG);
822 }
823
824 /* set number of clocks to wait after each ZQ command */
825 if (emc->zcal_long)
826 writel_relaxed(timing->emc_zcal_cnt_long,
827 emc->regs + EMC_ZCAL_WAIT_CNT);
828
829 /* wait for writes to settle */
830 udelay(2);
831
832 /* update restored timing */
833 err = emc_seq_update_timing(emc);
834 if (!err)
835 emc->bad_state = false;
836
837 /* restore early ACK */
838 mc_writel(emc->mc, emc->mc_override, MC_EMEM_ARB_OVERRIDE);
839
840 return err;
841 }
842
emc_unprepare_timing_change(struct tegra_emc * emc,unsigned long rate)843 static int emc_unprepare_timing_change(struct tegra_emc *emc,
844 unsigned long rate)
845 {
846 if (!emc->bad_state) {
847 /* shouldn't ever happen in practice */
848 dev_err(emc->dev, "timing configuration can't be reverted\n");
849 emc->bad_state = true;
850 }
851
852 return 0;
853 }
854
emc_clk_change_notify(struct notifier_block * nb,unsigned long msg,void * data)855 static int emc_clk_change_notify(struct notifier_block *nb,
856 unsigned long msg, void *data)
857 {
858 struct tegra_emc *emc = container_of(nb, struct tegra_emc, clk_nb);
859 struct clk_notifier_data *cnd = data;
860 int err;
861
862 switch (msg) {
863 case PRE_RATE_CHANGE:
864 /*
865 * Disable interrupt since read accesses are prohibited after
866 * stalling.
867 */
868 disable_irq(emc->irq);
869 err = emc_prepare_timing_change(emc, cnd->new_rate);
870 enable_irq(emc->irq);
871 break;
872
873 case ABORT_RATE_CHANGE:
874 err = emc_unprepare_timing_change(emc, cnd->old_rate);
875 break;
876
877 case POST_RATE_CHANGE:
878 err = emc_complete_timing_change(emc, cnd->new_rate);
879 break;
880
881 default:
882 return NOTIFY_DONE;
883 }
884
885 return notifier_from_errno(err);
886 }
887
load_one_timing_from_dt(struct tegra_emc * emc,struct emc_timing * timing,struct device_node * node)888 static int load_one_timing_from_dt(struct tegra_emc *emc,
889 struct emc_timing *timing,
890 struct device_node *node)
891 {
892 u32 value;
893 int err;
894
895 err = of_property_read_u32(node, "clock-frequency", &value);
896 if (err) {
897 dev_err(emc->dev, "timing %pOF: failed to read rate: %d\n",
898 node, err);
899 return err;
900 }
901
902 timing->rate = value;
903
904 err = of_property_read_u32_array(node, "nvidia,emc-configuration",
905 timing->data,
906 ARRAY_SIZE(emc_timing_registers));
907 if (err) {
908 dev_err(emc->dev,
909 "timing %pOF: failed to read emc timing data: %d\n",
910 node, err);
911 return err;
912 }
913
914 #define EMC_READ_BOOL(prop, dtprop) \
915 timing->prop = of_property_read_bool(node, dtprop);
916
917 #define EMC_READ_U32(prop, dtprop) \
918 err = of_property_read_u32(node, dtprop, &timing->prop); \
919 if (err) { \
920 dev_err(emc->dev, \
921 "timing %pOFn: failed to read " #prop ": %d\n", \
922 node, err); \
923 return err; \
924 }
925
926 EMC_READ_U32(emc_auto_cal_interval, "nvidia,emc-auto-cal-interval")
927 EMC_READ_U32(emc_mode_1, "nvidia,emc-mode-1")
928 EMC_READ_U32(emc_mode_2, "nvidia,emc-mode-2")
929 EMC_READ_U32(emc_mode_reset, "nvidia,emc-mode-reset")
930 EMC_READ_U32(emc_zcal_cnt_long, "nvidia,emc-zcal-cnt-long")
931 EMC_READ_BOOL(emc_cfg_dyn_self_ref, "nvidia,emc-cfg-dyn-self-ref")
932 EMC_READ_BOOL(emc_cfg_periodic_qrst, "nvidia,emc-cfg-periodic-qrst")
933
934 #undef EMC_READ_U32
935 #undef EMC_READ_BOOL
936
937 dev_dbg(emc->dev, "%s: %pOF: rate %lu\n", __func__, node, timing->rate);
938
939 return 0;
940 }
941
cmp_timings(const void * _a,const void * _b)942 static int cmp_timings(const void *_a, const void *_b)
943 {
944 const struct emc_timing *a = _a;
945 const struct emc_timing *b = _b;
946
947 if (a->rate < b->rate)
948 return -1;
949
950 if (a->rate > b->rate)
951 return 1;
952
953 return 0;
954 }
955
emc_check_mc_timings(struct tegra_emc * emc)956 static int emc_check_mc_timings(struct tegra_emc *emc)
957 {
958 struct tegra_mc *mc = emc->mc;
959 unsigned int i;
960
961 if (emc->num_timings != mc->num_timings) {
962 dev_err(emc->dev, "emc/mc timings number mismatch: %u %u\n",
963 emc->num_timings, mc->num_timings);
964 return -EINVAL;
965 }
966
967 for (i = 0; i < mc->num_timings; i++) {
968 if (emc->timings[i].rate != mc->timings[i].rate) {
969 dev_err(emc->dev,
970 "emc/mc timing rate mismatch: %lu %lu\n",
971 emc->timings[i].rate, mc->timings[i].rate);
972 return -EINVAL;
973 }
974 }
975
976 return 0;
977 }
978
emc_load_timings_from_dt(struct tegra_emc * emc,struct device_node * node)979 static int emc_load_timings_from_dt(struct tegra_emc *emc,
980 struct device_node *node)
981 {
982 struct device_node *child;
983 struct emc_timing *timing;
984 int child_count;
985 int err;
986
987 child_count = of_get_child_count(node);
988 if (!child_count) {
989 dev_err(emc->dev, "no memory timings in: %pOF\n", node);
990 return -EINVAL;
991 }
992
993 emc->timings = devm_kcalloc(emc->dev, child_count, sizeof(*timing),
994 GFP_KERNEL);
995 if (!emc->timings)
996 return -ENOMEM;
997
998 emc->num_timings = child_count;
999 timing = emc->timings;
1000
1001 for_each_child_of_node(node, child) {
1002 err = load_one_timing_from_dt(emc, timing++, child);
1003 if (err) {
1004 of_node_put(child);
1005 return err;
1006 }
1007 }
1008
1009 sort(emc->timings, emc->num_timings, sizeof(*timing), cmp_timings,
1010 NULL);
1011
1012 err = emc_check_mc_timings(emc);
1013 if (err)
1014 return err;
1015
1016 dev_info_once(emc->dev,
1017 "got %u timings for RAM code %u (min %luMHz max %luMHz)\n",
1018 emc->num_timings,
1019 tegra_read_ram_code(),
1020 emc->timings[0].rate / 1000000,
1021 emc->timings[emc->num_timings - 1].rate / 1000000);
1022
1023 return 0;
1024 }
1025
emc_find_node_by_ram_code(struct tegra_emc * emc)1026 static struct device_node *emc_find_node_by_ram_code(struct tegra_emc *emc)
1027 {
1028 struct device *dev = emc->dev;
1029 struct device_node *np;
1030 u32 value, ram_code;
1031 int err;
1032
1033 if (emc->mrr_error) {
1034 dev_warn(dev, "memory timings skipped due to MRR error\n");
1035 return NULL;
1036 }
1037
1038 if (of_get_child_count(dev->of_node) == 0) {
1039 dev_info_once(dev, "device-tree doesn't have memory timings\n");
1040 return NULL;
1041 }
1042
1043 ram_code = tegra_read_ram_code();
1044
1045 for_each_child_of_node(dev->of_node, np) {
1046 err = of_property_read_u32(np, "nvidia,ram-code", &value);
1047 if (err || value != ram_code)
1048 continue;
1049
1050 return np;
1051 }
1052
1053 dev_err(dev, "no memory timings for RAM code %u found in device-tree\n",
1054 ram_code);
1055
1056 return NULL;
1057 }
1058
emc_read_lpddr_mode_register(struct tegra_emc * emc,unsigned int emem_dev,unsigned int register_addr,unsigned int * register_data)1059 static int emc_read_lpddr_mode_register(struct tegra_emc *emc,
1060 unsigned int emem_dev,
1061 unsigned int register_addr,
1062 unsigned int *register_data)
1063 {
1064 u32 memory_dev = emem_dev ? 1 : 2;
1065 u32 val, mr_mask = 0xff;
1066 int err;
1067
1068 /* clear data-valid interrupt status */
1069 writel_relaxed(EMC_MRR_DIVLD_INT, emc->regs + EMC_INTSTATUS);
1070
1071 /* issue mode register read request */
1072 val = FIELD_PREP(EMC_MRR_DEV_SELECTN, memory_dev);
1073 val |= FIELD_PREP(EMC_MRR_MRR_MA, register_addr);
1074
1075 writel_relaxed(val, emc->regs + EMC_MRR);
1076
1077 /* wait for the LPDDR2 data-valid interrupt */
1078 err = readl_relaxed_poll_timeout_atomic(emc->regs + EMC_INTSTATUS, val,
1079 val & EMC_MRR_DIVLD_INT,
1080 1, 100);
1081 if (err) {
1082 dev_err(emc->dev, "mode register %u read failed: %d\n",
1083 register_addr, err);
1084 emc->mrr_error = true;
1085 return err;
1086 }
1087
1088 /* read out mode register data */
1089 val = readl_relaxed(emc->regs + EMC_MRR);
1090 *register_data = FIELD_GET(EMC_MRR_MRR_DATA, val) & mr_mask;
1091
1092 return 0;
1093 }
1094
emc_read_lpddr_sdram_info(struct tegra_emc * emc,unsigned int emem_dev)1095 static void emc_read_lpddr_sdram_info(struct tegra_emc *emc,
1096 unsigned int emem_dev)
1097 {
1098 union lpddr2_basic_config4 basic_conf4;
1099 unsigned int manufacturer_id;
1100 unsigned int revision_id1;
1101 unsigned int revision_id2;
1102
1103 /* these registers are standard for all LPDDR JEDEC memory chips */
1104 emc_read_lpddr_mode_register(emc, emem_dev, 5, &manufacturer_id);
1105 emc_read_lpddr_mode_register(emc, emem_dev, 6, &revision_id1);
1106 emc_read_lpddr_mode_register(emc, emem_dev, 7, &revision_id2);
1107 emc_read_lpddr_mode_register(emc, emem_dev, 8, &basic_conf4.value);
1108
1109 dev_info(emc->dev, "SDRAM[dev%u]: manufacturer: 0x%x (%s) rev1: 0x%x rev2: 0x%x prefetch: S%u density: %uMbit iowidth: %ubit\n",
1110 emem_dev, manufacturer_id,
1111 lpddr2_jedec_manufacturer(manufacturer_id),
1112 revision_id1, revision_id2,
1113 4 >> basic_conf4.arch_type,
1114 64 << basic_conf4.density,
1115 32 >> basic_conf4.io_width);
1116 }
1117
emc_setup_hw(struct tegra_emc * emc)1118 static int emc_setup_hw(struct tegra_emc *emc)
1119 {
1120 u32 fbio_cfg5, emc_cfg, emc_dbg, emc_adr_cfg;
1121 u32 intmask = EMC_REFRESH_OVERFLOW_INT;
1122 static bool print_sdram_info_once;
1123 enum emc_dram_type dram_type;
1124 const char *dram_type_str;
1125 unsigned int emem_numdev;
1126
1127 fbio_cfg5 = readl_relaxed(emc->regs + EMC_FBIO_CFG5);
1128 dram_type = fbio_cfg5 & EMC_FBIO_CFG5_DRAM_TYPE_MASK;
1129
1130 emc_cfg = readl_relaxed(emc->regs + EMC_CFG_2);
1131
1132 /* enable EMC and CAR to handshake on PLL divider/source changes */
1133 emc_cfg |= EMC_CLKCHANGE_REQ_ENABLE;
1134
1135 /* configure clock change mode accordingly to DRAM type */
1136 switch (dram_type) {
1137 case DRAM_TYPE_LPDDR2:
1138 emc_cfg |= EMC_CLKCHANGE_PD_ENABLE;
1139 emc_cfg &= ~EMC_CLKCHANGE_SR_ENABLE;
1140 break;
1141
1142 default:
1143 emc_cfg &= ~EMC_CLKCHANGE_SR_ENABLE;
1144 emc_cfg &= ~EMC_CLKCHANGE_PD_ENABLE;
1145 break;
1146 }
1147
1148 writel_relaxed(emc_cfg, emc->regs + EMC_CFG_2);
1149
1150 /* initialize interrupt */
1151 writel_relaxed(intmask, emc->regs + EMC_INTMASK);
1152 writel_relaxed(0xffffffff, emc->regs + EMC_INTSTATUS);
1153
1154 /* ensure that unwanted debug features are disabled */
1155 emc_dbg = readl_relaxed(emc->regs + EMC_DBG);
1156 emc_dbg |= EMC_DBG_CFG_PRIORITY;
1157 emc_dbg &= ~EMC_DBG_READ_MUX_ASSEMBLY;
1158 emc_dbg &= ~EMC_DBG_WRITE_MUX_ACTIVE;
1159 emc_dbg &= ~EMC_DBG_FORCE_UPDATE;
1160 writel_relaxed(emc_dbg, emc->regs + EMC_DBG);
1161
1162 switch (dram_type) {
1163 case DRAM_TYPE_DDR1:
1164 dram_type_str = "DDR1";
1165 break;
1166 case DRAM_TYPE_LPDDR2:
1167 dram_type_str = "LPDDR2";
1168 break;
1169 case DRAM_TYPE_DDR2:
1170 dram_type_str = "DDR2";
1171 break;
1172 case DRAM_TYPE_DDR3:
1173 dram_type_str = "DDR3";
1174 break;
1175 }
1176
1177 emc_adr_cfg = readl_relaxed(emc->regs + EMC_ADR_CFG);
1178 emem_numdev = FIELD_GET(EMC_ADR_CFG_EMEM_NUMDEV, emc_adr_cfg) + 1;
1179
1180 dev_info_once(emc->dev, "%u %s %s attached\n", emem_numdev,
1181 dram_type_str, emem_numdev == 2 ? "devices" : "device");
1182
1183 if (dram_type == DRAM_TYPE_LPDDR2 && !print_sdram_info_once) {
1184 while (emem_numdev--)
1185 emc_read_lpddr_sdram_info(emc, emem_numdev);
1186
1187 print_sdram_info_once = true;
1188 }
1189
1190 return 0;
1191 }
1192
emc_round_rate(unsigned long rate,unsigned long min_rate,unsigned long max_rate,void * arg)1193 static long emc_round_rate(unsigned long rate,
1194 unsigned long min_rate,
1195 unsigned long max_rate,
1196 void *arg)
1197 {
1198 struct emc_timing *timing = NULL;
1199 struct tegra_emc *emc = arg;
1200 unsigned int i;
1201
1202 if (!emc->num_timings)
1203 return clk_get_rate(emc->clk);
1204
1205 min_rate = min(min_rate, emc->timings[emc->num_timings - 1].rate);
1206
1207 for (i = 0; i < emc->num_timings; i++) {
1208 if (emc->timings[i].rate < rate && i != emc->num_timings - 1)
1209 continue;
1210
1211 if (emc->timings[i].rate > max_rate) {
1212 i = max(i, 1u) - 1;
1213
1214 if (emc->timings[i].rate < min_rate)
1215 break;
1216 }
1217
1218 if (emc->timings[i].rate < min_rate)
1219 continue;
1220
1221 timing = &emc->timings[i];
1222 break;
1223 }
1224
1225 if (!timing) {
1226 dev_err(emc->dev, "no timing for rate %lu min %lu max %lu\n",
1227 rate, min_rate, max_rate);
1228 return -EINVAL;
1229 }
1230
1231 return timing->rate;
1232 }
1233
tegra_emc_rate_requests_init(struct tegra_emc * emc)1234 static void tegra_emc_rate_requests_init(struct tegra_emc *emc)
1235 {
1236 unsigned int i;
1237
1238 for (i = 0; i < EMC_RATE_TYPE_MAX; i++) {
1239 emc->requested_rate[i].min_rate = 0;
1240 emc->requested_rate[i].max_rate = ULONG_MAX;
1241 }
1242 }
1243
emc_request_rate(struct tegra_emc * emc,unsigned long new_min_rate,unsigned long new_max_rate,enum emc_rate_request_type type)1244 static int emc_request_rate(struct tegra_emc *emc,
1245 unsigned long new_min_rate,
1246 unsigned long new_max_rate,
1247 enum emc_rate_request_type type)
1248 {
1249 struct emc_rate_request *req = emc->requested_rate;
1250 unsigned long min_rate = 0, max_rate = ULONG_MAX;
1251 unsigned int i;
1252 int err;
1253
1254 /* select minimum and maximum rates among the requested rates */
1255 for (i = 0; i < EMC_RATE_TYPE_MAX; i++, req++) {
1256 if (i == type) {
1257 min_rate = max(new_min_rate, min_rate);
1258 max_rate = min(new_max_rate, max_rate);
1259 } else {
1260 min_rate = max(req->min_rate, min_rate);
1261 max_rate = min(req->max_rate, max_rate);
1262 }
1263 }
1264
1265 if (min_rate > max_rate) {
1266 dev_err_ratelimited(emc->dev, "%s: type %u: out of range: %lu %lu\n",
1267 __func__, type, min_rate, max_rate);
1268 return -ERANGE;
1269 }
1270
1271 /*
1272 * EMC rate-changes should go via OPP API because it manages voltage
1273 * changes.
1274 */
1275 err = dev_pm_opp_set_rate(emc->dev, min_rate);
1276 if (err)
1277 return err;
1278
1279 emc->requested_rate[type].min_rate = new_min_rate;
1280 emc->requested_rate[type].max_rate = new_max_rate;
1281
1282 return 0;
1283 }
1284
emc_set_min_rate(struct tegra_emc * emc,unsigned long rate,enum emc_rate_request_type type)1285 static int emc_set_min_rate(struct tegra_emc *emc, unsigned long rate,
1286 enum emc_rate_request_type type)
1287 {
1288 struct emc_rate_request *req = &emc->requested_rate[type];
1289 int ret;
1290
1291 mutex_lock(&emc->rate_lock);
1292 ret = emc_request_rate(emc, rate, req->max_rate, type);
1293 mutex_unlock(&emc->rate_lock);
1294
1295 return ret;
1296 }
1297
emc_set_max_rate(struct tegra_emc * emc,unsigned long rate,enum emc_rate_request_type type)1298 static int emc_set_max_rate(struct tegra_emc *emc, unsigned long rate,
1299 enum emc_rate_request_type type)
1300 {
1301 struct emc_rate_request *req = &emc->requested_rate[type];
1302 int ret;
1303
1304 mutex_lock(&emc->rate_lock);
1305 ret = emc_request_rate(emc, req->min_rate, rate, type);
1306 mutex_unlock(&emc->rate_lock);
1307
1308 return ret;
1309 }
1310
1311 /*
1312 * debugfs interface
1313 *
1314 * The memory controller driver exposes some files in debugfs that can be used
1315 * to control the EMC frequency. The top-level directory can be found here:
1316 *
1317 * /sys/kernel/debug/emc
1318 *
1319 * It contains the following files:
1320 *
1321 * - available_rates: This file contains a list of valid, space-separated
1322 * EMC frequencies.
1323 *
1324 * - min_rate: Writing a value to this file sets the given frequency as the
1325 * floor of the permitted range. If this is higher than the currently
1326 * configured EMC frequency, this will cause the frequency to be
1327 * increased so that it stays within the valid range.
1328 *
1329 * - max_rate: Similarily to the min_rate file, writing a value to this file
1330 * sets the given frequency as the ceiling of the permitted range. If
1331 * the value is lower than the currently configured EMC frequency, this
1332 * will cause the frequency to be decreased so that it stays within the
1333 * valid range.
1334 */
1335
tegra_emc_validate_rate(struct tegra_emc * emc,unsigned long rate)1336 static bool tegra_emc_validate_rate(struct tegra_emc *emc, unsigned long rate)
1337 {
1338 unsigned int i;
1339
1340 for (i = 0; i < emc->num_timings; i++)
1341 if (rate == emc->timings[i].rate)
1342 return true;
1343
1344 return false;
1345 }
1346
tegra_emc_debug_available_rates_show(struct seq_file * s,void * data)1347 static int tegra_emc_debug_available_rates_show(struct seq_file *s, void *data)
1348 {
1349 struct tegra_emc *emc = s->private;
1350 const char *prefix = "";
1351 unsigned int i;
1352
1353 for (i = 0; i < emc->num_timings; i++) {
1354 seq_printf(s, "%s%lu", prefix, emc->timings[i].rate);
1355 prefix = " ";
1356 }
1357
1358 seq_puts(s, "\n");
1359
1360 return 0;
1361 }
1362 DEFINE_SHOW_ATTRIBUTE(tegra_emc_debug_available_rates);
1363
tegra_emc_debug_min_rate_get(void * data,u64 * rate)1364 static int tegra_emc_debug_min_rate_get(void *data, u64 *rate)
1365 {
1366 struct tegra_emc *emc = data;
1367
1368 *rate = emc->debugfs.min_rate;
1369
1370 return 0;
1371 }
1372
tegra_emc_debug_min_rate_set(void * data,u64 rate)1373 static int tegra_emc_debug_min_rate_set(void *data, u64 rate)
1374 {
1375 struct tegra_emc *emc = data;
1376 int err;
1377
1378 if (!tegra_emc_validate_rate(emc, rate))
1379 return -EINVAL;
1380
1381 err = emc_set_min_rate(emc, rate, EMC_RATE_DEBUG);
1382 if (err < 0)
1383 return err;
1384
1385 emc->debugfs.min_rate = rate;
1386
1387 return 0;
1388 }
1389
1390 DEFINE_DEBUGFS_ATTRIBUTE(tegra_emc_debug_min_rate_fops,
1391 tegra_emc_debug_min_rate_get,
1392 tegra_emc_debug_min_rate_set, "%llu\n");
1393
tegra_emc_debug_max_rate_get(void * data,u64 * rate)1394 static int tegra_emc_debug_max_rate_get(void *data, u64 *rate)
1395 {
1396 struct tegra_emc *emc = data;
1397
1398 *rate = emc->debugfs.max_rate;
1399
1400 return 0;
1401 }
1402
tegra_emc_debug_max_rate_set(void * data,u64 rate)1403 static int tegra_emc_debug_max_rate_set(void *data, u64 rate)
1404 {
1405 struct tegra_emc *emc = data;
1406 int err;
1407
1408 if (!tegra_emc_validate_rate(emc, rate))
1409 return -EINVAL;
1410
1411 err = emc_set_max_rate(emc, rate, EMC_RATE_DEBUG);
1412 if (err < 0)
1413 return err;
1414
1415 emc->debugfs.max_rate = rate;
1416
1417 return 0;
1418 }
1419
1420 DEFINE_DEBUGFS_ATTRIBUTE(tegra_emc_debug_max_rate_fops,
1421 tegra_emc_debug_max_rate_get,
1422 tegra_emc_debug_max_rate_set, "%llu\n");
1423
tegra_emc_debugfs_init(struct tegra_emc * emc)1424 static void tegra_emc_debugfs_init(struct tegra_emc *emc)
1425 {
1426 struct device *dev = emc->dev;
1427 unsigned int i;
1428 int err;
1429
1430 emc->debugfs.min_rate = ULONG_MAX;
1431 emc->debugfs.max_rate = 0;
1432
1433 for (i = 0; i < emc->num_timings; i++) {
1434 if (emc->timings[i].rate < emc->debugfs.min_rate)
1435 emc->debugfs.min_rate = emc->timings[i].rate;
1436
1437 if (emc->timings[i].rate > emc->debugfs.max_rate)
1438 emc->debugfs.max_rate = emc->timings[i].rate;
1439 }
1440
1441 if (!emc->num_timings) {
1442 emc->debugfs.min_rate = clk_get_rate(emc->clk);
1443 emc->debugfs.max_rate = emc->debugfs.min_rate;
1444 }
1445
1446 err = clk_set_rate_range(emc->clk, emc->debugfs.min_rate,
1447 emc->debugfs.max_rate);
1448 if (err < 0) {
1449 dev_err(dev, "failed to set rate range [%lu-%lu] for %pC\n",
1450 emc->debugfs.min_rate, emc->debugfs.max_rate,
1451 emc->clk);
1452 }
1453
1454 emc->debugfs.root = debugfs_create_dir("emc", NULL);
1455
1456 debugfs_create_file("available_rates", 0444, emc->debugfs.root,
1457 emc, &tegra_emc_debug_available_rates_fops);
1458 debugfs_create_file("min_rate", 0644, emc->debugfs.root,
1459 emc, &tegra_emc_debug_min_rate_fops);
1460 debugfs_create_file("max_rate", 0644, emc->debugfs.root,
1461 emc, &tegra_emc_debug_max_rate_fops);
1462 }
1463
1464 static inline struct tegra_emc *
to_tegra_emc_provider(struct icc_provider * provider)1465 to_tegra_emc_provider(struct icc_provider *provider)
1466 {
1467 return container_of(provider, struct tegra_emc, provider);
1468 }
1469
1470 static struct icc_node_data *
emc_of_icc_xlate_extended(struct of_phandle_args * spec,void * data)1471 emc_of_icc_xlate_extended(struct of_phandle_args *spec, void *data)
1472 {
1473 struct icc_provider *provider = data;
1474 struct icc_node_data *ndata;
1475 struct icc_node *node;
1476
1477 /* External Memory is the only possible ICC route */
1478 list_for_each_entry(node, &provider->nodes, node_list) {
1479 if (node->id != TEGRA_ICC_EMEM)
1480 continue;
1481
1482 ndata = kzalloc(sizeof(*ndata), GFP_KERNEL);
1483 if (!ndata)
1484 return ERR_PTR(-ENOMEM);
1485
1486 /*
1487 * SRC and DST nodes should have matching TAG in order to have
1488 * it set by default for a requested path.
1489 */
1490 ndata->tag = TEGRA_MC_ICC_TAG_ISO;
1491 ndata->node = node;
1492
1493 return ndata;
1494 }
1495
1496 return ERR_PTR(-EPROBE_DEFER);
1497 }
1498
emc_icc_set(struct icc_node * src,struct icc_node * dst)1499 static int emc_icc_set(struct icc_node *src, struct icc_node *dst)
1500 {
1501 struct tegra_emc *emc = to_tegra_emc_provider(dst->provider);
1502 unsigned long long peak_bw = icc_units_to_bps(dst->peak_bw);
1503 unsigned long long avg_bw = icc_units_to_bps(dst->avg_bw);
1504 unsigned long long rate = max(avg_bw, peak_bw);
1505 const unsigned int dram_data_bus_width_bytes = 4;
1506 const unsigned int ddr = 2;
1507 int err;
1508
1509 /*
1510 * Tegra30 EMC runs on a clock rate of SDRAM bus. This means that
1511 * EMC clock rate is twice smaller than the peak data rate because
1512 * data is sampled on both EMC clock edges.
1513 */
1514 do_div(rate, ddr * dram_data_bus_width_bytes);
1515 rate = min_t(u64, rate, U32_MAX);
1516
1517 err = emc_set_min_rate(emc, rate, EMC_RATE_ICC);
1518 if (err)
1519 return err;
1520
1521 return 0;
1522 }
1523
tegra_emc_interconnect_init(struct tegra_emc * emc)1524 static int tegra_emc_interconnect_init(struct tegra_emc *emc)
1525 {
1526 const struct tegra_mc_soc *soc = emc->mc->soc;
1527 struct icc_node *node;
1528 int err;
1529
1530 emc->provider.dev = emc->dev;
1531 emc->provider.set = emc_icc_set;
1532 emc->provider.data = &emc->provider;
1533 emc->provider.aggregate = soc->icc_ops->aggregate;
1534 emc->provider.xlate_extended = emc_of_icc_xlate_extended;
1535
1536 icc_provider_init(&emc->provider);
1537
1538 /* create External Memory Controller node */
1539 node = icc_node_create(TEGRA_ICC_EMC);
1540 if (IS_ERR(node)) {
1541 err = PTR_ERR(node);
1542 goto err_msg;
1543 }
1544
1545 node->name = "External Memory Controller";
1546 icc_node_add(node, &emc->provider);
1547
1548 /* link External Memory Controller to External Memory (DRAM) */
1549 err = icc_link_create(node, TEGRA_ICC_EMEM);
1550 if (err)
1551 goto remove_nodes;
1552
1553 /* create External Memory node */
1554 node = icc_node_create(TEGRA_ICC_EMEM);
1555 if (IS_ERR(node)) {
1556 err = PTR_ERR(node);
1557 goto remove_nodes;
1558 }
1559
1560 node->name = "External Memory (DRAM)";
1561 icc_node_add(node, &emc->provider);
1562
1563 err = icc_provider_register(&emc->provider);
1564 if (err)
1565 goto remove_nodes;
1566
1567 return 0;
1568
1569 remove_nodes:
1570 icc_nodes_remove(&emc->provider);
1571 err_msg:
1572 dev_err(emc->dev, "failed to initialize ICC: %d\n", err);
1573
1574 return err;
1575 }
1576
devm_tegra_emc_unset_callback(void * data)1577 static void devm_tegra_emc_unset_callback(void *data)
1578 {
1579 tegra20_clk_set_emc_round_callback(NULL, NULL);
1580 }
1581
devm_tegra_emc_unreg_clk_notifier(void * data)1582 static void devm_tegra_emc_unreg_clk_notifier(void *data)
1583 {
1584 struct tegra_emc *emc = data;
1585
1586 clk_notifier_unregister(emc->clk, &emc->clk_nb);
1587 }
1588
tegra_emc_init_clk(struct tegra_emc * emc)1589 static int tegra_emc_init_clk(struct tegra_emc *emc)
1590 {
1591 int err;
1592
1593 tegra20_clk_set_emc_round_callback(emc_round_rate, emc);
1594
1595 err = devm_add_action_or_reset(emc->dev, devm_tegra_emc_unset_callback,
1596 NULL);
1597 if (err)
1598 return err;
1599
1600 emc->clk = devm_clk_get(emc->dev, NULL);
1601 if (IS_ERR(emc->clk)) {
1602 dev_err(emc->dev, "failed to get EMC clock: %pe\n", emc->clk);
1603 return PTR_ERR(emc->clk);
1604 }
1605
1606 err = clk_notifier_register(emc->clk, &emc->clk_nb);
1607 if (err) {
1608 dev_err(emc->dev, "failed to register clk notifier: %d\n", err);
1609 return err;
1610 }
1611
1612 err = devm_add_action_or_reset(emc->dev,
1613 devm_tegra_emc_unreg_clk_notifier, emc);
1614 if (err)
1615 return err;
1616
1617 return 0;
1618 }
1619
tegra_emc_probe(struct platform_device * pdev)1620 static int tegra_emc_probe(struct platform_device *pdev)
1621 {
1622 struct tegra_core_opp_params opp_params = {};
1623 struct device_node *np;
1624 struct tegra_emc *emc;
1625 int err;
1626
1627 emc = devm_kzalloc(&pdev->dev, sizeof(*emc), GFP_KERNEL);
1628 if (!emc)
1629 return -ENOMEM;
1630
1631 emc->mc = devm_tegra_memory_controller_get(&pdev->dev);
1632 if (IS_ERR(emc->mc))
1633 return PTR_ERR(emc->mc);
1634
1635 mutex_init(&emc->rate_lock);
1636 emc->clk_nb.notifier_call = emc_clk_change_notify;
1637 emc->dev = &pdev->dev;
1638
1639 emc->regs = devm_platform_ioremap_resource(pdev, 0);
1640 if (IS_ERR(emc->regs))
1641 return PTR_ERR(emc->regs);
1642
1643 err = emc_setup_hw(emc);
1644 if (err)
1645 return err;
1646
1647 np = emc_find_node_by_ram_code(emc);
1648 if (np) {
1649 err = emc_load_timings_from_dt(emc, np);
1650 of_node_put(np);
1651 if (err)
1652 return err;
1653 }
1654
1655 err = platform_get_irq(pdev, 0);
1656 if (err < 0)
1657 return err;
1658
1659 emc->irq = err;
1660
1661 err = devm_request_irq(&pdev->dev, emc->irq, tegra_emc_isr, 0,
1662 dev_name(&pdev->dev), emc);
1663 if (err) {
1664 dev_err(&pdev->dev, "failed to request irq: %d\n", err);
1665 return err;
1666 }
1667
1668 err = tegra_emc_init_clk(emc);
1669 if (err)
1670 return err;
1671
1672 opp_params.init_state = true;
1673
1674 err = devm_tegra_core_dev_init_opp_table(&pdev->dev, &opp_params);
1675 if (err)
1676 return err;
1677
1678 platform_set_drvdata(pdev, emc);
1679 tegra_emc_rate_requests_init(emc);
1680 tegra_emc_debugfs_init(emc);
1681 tegra_emc_interconnect_init(emc);
1682
1683 /*
1684 * Don't allow the kernel module to be unloaded. Unloading adds some
1685 * extra complexity which doesn't really worth the effort in a case of
1686 * this driver.
1687 */
1688 try_module_get(THIS_MODULE);
1689
1690 return 0;
1691 }
1692
tegra_emc_suspend(struct device * dev)1693 static int tegra_emc_suspend(struct device *dev)
1694 {
1695 struct tegra_emc *emc = dev_get_drvdata(dev);
1696 int err;
1697
1698 /* take exclusive control over the clock's rate */
1699 err = clk_rate_exclusive_get(emc->clk);
1700 if (err) {
1701 dev_err(emc->dev, "failed to acquire clk: %d\n", err);
1702 return err;
1703 }
1704
1705 /* suspending in a bad state will hang machine */
1706 if (WARN(emc->bad_state, "hardware in a bad state\n"))
1707 return -EINVAL;
1708
1709 emc->bad_state = true;
1710
1711 return 0;
1712 }
1713
tegra_emc_resume(struct device * dev)1714 static int tegra_emc_resume(struct device *dev)
1715 {
1716 struct tegra_emc *emc = dev_get_drvdata(dev);
1717
1718 emc_setup_hw(emc);
1719 emc->bad_state = false;
1720
1721 clk_rate_exclusive_put(emc->clk);
1722
1723 return 0;
1724 }
1725
1726 static const struct dev_pm_ops tegra_emc_pm_ops = {
1727 .suspend = tegra_emc_suspend,
1728 .resume = tegra_emc_resume,
1729 };
1730
1731 static const struct of_device_id tegra_emc_of_match[] = {
1732 { .compatible = "nvidia,tegra30-emc", },
1733 {},
1734 };
1735 MODULE_DEVICE_TABLE(of, tegra_emc_of_match);
1736
1737 static struct platform_driver tegra_emc_driver = {
1738 .probe = tegra_emc_probe,
1739 .driver = {
1740 .name = "tegra30-emc",
1741 .of_match_table = tegra_emc_of_match,
1742 .pm = &tegra_emc_pm_ops,
1743 .suppress_bind_attrs = true,
1744 .sync_state = icc_sync_state,
1745 },
1746 };
1747 module_platform_driver(tegra_emc_driver);
1748
1749 MODULE_AUTHOR("Dmitry Osipenko <digetx@gmail.com>");
1750 MODULE_DESCRIPTION("NVIDIA Tegra30 EMC driver");
1751 MODULE_LICENSE("GPL v2");
1752