1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2020 BAIKAL ELECTRONICS, JSC
4 *
5 * Authors:
6 * Serge Semin <Sergey.Semin@baikalelectronics.ru>
7 * Dmitry Dunaev <dmitry.dunaev@baikalelectronics.ru>
8 *
9 * Baikal-T1 CCU Dividers clock driver
10 */
11
12#define pr_fmt(fmt) "bt1-ccu-div: " fmt
13
14#include <linux/kernel.h>
15#include <linux/platform_device.h>
16#include <linux/printk.h>
17#include <linux/slab.h>
18#include <linux/clk-provider.h>
19#include <linux/reset-controller.h>
20#include <linux/mfd/syscon.h>
21#include <linux/of.h>
22#include <linux/of_address.h>
23#include <linux/ioport.h>
24#include <linux/regmap.h>
25
26#include <dt-bindings/clock/bt1-ccu.h>
27
28#include "ccu-div.h"
29#include "ccu-rst.h"
30
31#define CCU_AXI_MAIN_BASE 0x030
32#define CCU_AXI_DDR_BASE 0x034
33#define CCU_AXI_SATA_BASE 0x038
34#define CCU_AXI_GMAC0_BASE 0x03C
35#define CCU_AXI_GMAC1_BASE 0x040
36#define CCU_AXI_XGMAC_BASE 0x044
37#define CCU_AXI_PCIE_M_BASE 0x048
38#define CCU_AXI_PCIE_S_BASE 0x04C
39#define CCU_AXI_USB_BASE 0x050
40#define CCU_AXI_HWA_BASE 0x054
41#define CCU_AXI_SRAM_BASE 0x058
42
43#define CCU_SYS_SATA_REF_BASE 0x060
44#define CCU_SYS_APB_BASE 0x064
45#define CCU_SYS_GMAC0_BASE 0x068
46#define CCU_SYS_GMAC1_BASE 0x06C
47#define CCU_SYS_XGMAC_BASE 0x070
48#define CCU_SYS_USB_BASE 0x074
49#define CCU_SYS_PVT_BASE 0x078
50#define CCU_SYS_HWA_BASE 0x07C
51#define CCU_SYS_UART_BASE 0x084
52#define CCU_SYS_TIMER0_BASE 0x088
53#define CCU_SYS_TIMER1_BASE 0x08C
54#define CCU_SYS_TIMER2_BASE 0x090
55#define CCU_SYS_WDT_BASE 0x150
56
57#define CCU_DIV_VAR_INFO(_id, _name, _pname, _base, _width, _flags, _features) \
58 { \
59 .id = _id, \
60 .name = _name, \
61 .parent_name = _pname, \
62 .base = _base, \
63 .type = CCU_DIV_VAR, \
64 .width = _width, \
65 .flags = _flags, \
66 .features = _features \
67 }
68
69#define CCU_DIV_GATE_INFO(_id, _name, _pname, _base, _divider) \
70 { \
71 .id = _id, \
72 .name = _name, \
73 .parent_name = _pname, \
74 .base = _base, \
75 .type = CCU_DIV_GATE, \
76 .divider = _divider \
77 }
78
79#define CCU_DIV_BUF_INFO(_id, _name, _pname, _base, _flags) \
80 { \
81 .id = _id, \
82 .name = _name, \
83 .parent_name = _pname, \
84 .base = _base, \
85 .type = CCU_DIV_BUF, \
86 .flags = _flags \
87 }
88
89#define CCU_DIV_FIXED_INFO(_id, _name, _pname, _divider) \
90 { \
91 .id = _id, \
92 .name = _name, \
93 .parent_name = _pname, \
94 .type = CCU_DIV_FIXED, \
95 .divider = _divider \
96 }
97
98struct ccu_div_info {
99 unsigned int id;
100 const char *name;
101 const char *parent_name;
102 unsigned int base;
103 enum ccu_div_type type;
104 union {
105 unsigned int width;
106 unsigned int divider;
107 };
108 unsigned long flags;
109 unsigned long features;
110};
111
112struct ccu_div_data {
113 struct device_node *np;
114 struct regmap *sys_regs;
115
116 unsigned int divs_num;
117 const struct ccu_div_info *divs_info;
118 struct ccu_div **divs;
119
120 struct ccu_rst *rsts;
121};
122
123/*
124 * AXI Main Interconnect (axi_main_clk) and DDR AXI-bus (axi_ddr_clk) clocks
125 * must be left enabled in any case, since former one is responsible for
126 * clocking a bus between CPU cores and the rest of the SoC components, while
127 * the later is clocking the AXI-bus between DDR controller and the Main
128 * Interconnect. So should any of these clocks get to be disabled, the system
129 * will literally stop working. That's why we marked them as critical.
130 */
131static const struct ccu_div_info axi_info[] = {
132 CCU_DIV_VAR_INFO(CCU_AXI_MAIN_CLK, "axi_main_clk", "pcie_clk",
133 CCU_AXI_MAIN_BASE, 4,
134 CLK_IS_CRITICAL, CCU_DIV_RESET_DOMAIN),
135 CCU_DIV_VAR_INFO(CCU_AXI_DDR_CLK, "axi_ddr_clk", "sata_clk",
136 CCU_AXI_DDR_BASE, 4,
137 CLK_IS_CRITICAL | CLK_SET_RATE_GATE,
138 CCU_DIV_RESET_DOMAIN),
139 CCU_DIV_VAR_INFO(CCU_AXI_SATA_CLK, "axi_sata_clk", "sata_clk",
140 CCU_AXI_SATA_BASE, 4,
141 CLK_SET_RATE_GATE, CCU_DIV_RESET_DOMAIN),
142 CCU_DIV_VAR_INFO(CCU_AXI_GMAC0_CLK, "axi_gmac0_clk", "eth_clk",
143 CCU_AXI_GMAC0_BASE, 4,
144 CLK_SET_RATE_GATE, CCU_DIV_RESET_DOMAIN),
145 CCU_DIV_VAR_INFO(CCU_AXI_GMAC1_CLK, "axi_gmac1_clk", "eth_clk",
146 CCU_AXI_GMAC1_BASE, 4,
147 CLK_SET_RATE_GATE, CCU_DIV_RESET_DOMAIN),
148 CCU_DIV_VAR_INFO(CCU_AXI_XGMAC_CLK, "axi_xgmac_clk", "eth_clk",
149 CCU_AXI_XGMAC_BASE, 4,
150 CLK_SET_RATE_GATE, CCU_DIV_RESET_DOMAIN),
151 CCU_DIV_VAR_INFO(CCU_AXI_PCIE_M_CLK, "axi_pcie_m_clk", "pcie_clk",
152 CCU_AXI_PCIE_M_BASE, 4,
153 CLK_SET_RATE_GATE, CCU_DIV_RESET_DOMAIN),
154 CCU_DIV_VAR_INFO(CCU_AXI_PCIE_S_CLK, "axi_pcie_s_clk", "pcie_clk",
155 CCU_AXI_PCIE_S_BASE, 4,
156 CLK_SET_RATE_GATE, CCU_DIV_RESET_DOMAIN),
157 CCU_DIV_VAR_INFO(CCU_AXI_USB_CLK, "axi_usb_clk", "sata_clk",
158 CCU_AXI_USB_BASE, 4,
159 CLK_SET_RATE_GATE, CCU_DIV_RESET_DOMAIN),
160 CCU_DIV_VAR_INFO(CCU_AXI_HWA_CLK, "axi_hwa_clk", "sata_clk",
161 CCU_AXI_HWA_BASE, 4,
162 CLK_SET_RATE_GATE, CCU_DIV_RESET_DOMAIN),
163 CCU_DIV_VAR_INFO(CCU_AXI_SRAM_CLK, "axi_sram_clk", "eth_clk",
164 CCU_AXI_SRAM_BASE, 4,
165 CLK_SET_RATE_GATE, CCU_DIV_RESET_DOMAIN)
166};
167
168/*
169 * APB-bus clock is marked as critical since it's a main communication bus
170 * for the SoC devices registers IO-operations.
171 */
172static const struct ccu_div_info sys_info[] = {
173 CCU_DIV_VAR_INFO(CCU_SYS_SATA_CLK, "sys_sata_clk",
174 "sata_clk", CCU_SYS_SATA_REF_BASE, 4,
175 CLK_SET_RATE_GATE,
176 CCU_DIV_SKIP_ONE | CCU_DIV_LOCK_SHIFTED |
177 CCU_DIV_RESET_DOMAIN),
178 CCU_DIV_BUF_INFO(CCU_SYS_SATA_REF_CLK, "sys_sata_ref_clk",
179 "sys_sata_clk", CCU_SYS_SATA_REF_BASE,
180 CLK_SET_RATE_PARENT),
181 CCU_DIV_VAR_INFO(CCU_SYS_APB_CLK, "sys_apb_clk",
182 "pcie_clk", CCU_SYS_APB_BASE, 5,
183 CLK_IS_CRITICAL, CCU_DIV_BASIC | CCU_DIV_RESET_DOMAIN),
184 CCU_DIV_GATE_INFO(CCU_SYS_GMAC0_TX_CLK, "sys_gmac0_tx_clk",
185 "eth_clk", CCU_SYS_GMAC0_BASE, 5),
186 CCU_DIV_FIXED_INFO(CCU_SYS_GMAC0_PTP_CLK, "sys_gmac0_ptp_clk",
187 "eth_clk", 10),
188 CCU_DIV_GATE_INFO(CCU_SYS_GMAC1_TX_CLK, "sys_gmac1_tx_clk",
189 "eth_clk", CCU_SYS_GMAC1_BASE, 5),
190 CCU_DIV_FIXED_INFO(CCU_SYS_GMAC1_PTP_CLK, "sys_gmac1_ptp_clk",
191 "eth_clk", 10),
192 CCU_DIV_GATE_INFO(CCU_SYS_XGMAC_CLK, "sys_xgmac_clk",
193 "eth_clk", CCU_SYS_XGMAC_BASE, 1),
194 CCU_DIV_FIXED_INFO(CCU_SYS_XGMAC_REF_CLK, "sys_xgmac_ref_clk",
195 "sys_xgmac_clk", 8),
196 CCU_DIV_FIXED_INFO(CCU_SYS_XGMAC_PTP_CLK, "sys_xgmac_ptp_clk",
197 "sys_xgmac_clk", 8),
198 CCU_DIV_GATE_INFO(CCU_SYS_USB_CLK, "sys_usb_clk",
199 "eth_clk", CCU_SYS_USB_BASE, 10),
200 CCU_DIV_VAR_INFO(CCU_SYS_PVT_CLK, "sys_pvt_clk",
201 "ref_clk", CCU_SYS_PVT_BASE, 5,
202 CLK_SET_RATE_GATE, 0),
203 CCU_DIV_VAR_INFO(CCU_SYS_HWA_CLK, "sys_hwa_clk",
204 "sata_clk", CCU_SYS_HWA_BASE, 4,
205 CLK_SET_RATE_GATE, 0),
206 CCU_DIV_VAR_INFO(CCU_SYS_UART_CLK, "sys_uart_clk",
207 "eth_clk", CCU_SYS_UART_BASE, 17,
208 CLK_SET_RATE_GATE, 0),
209 CCU_DIV_FIXED_INFO(CCU_SYS_I2C1_CLK, "sys_i2c1_clk",
210 "eth_clk", 10),
211 CCU_DIV_FIXED_INFO(CCU_SYS_I2C2_CLK, "sys_i2c2_clk",
212 "eth_clk", 10),
213 CCU_DIV_FIXED_INFO(CCU_SYS_GPIO_CLK, "sys_gpio_clk",
214 "ref_clk", 25),
215 CCU_DIV_VAR_INFO(CCU_SYS_TIMER0_CLK, "sys_timer0_clk",
216 "ref_clk", CCU_SYS_TIMER0_BASE, 17,
217 CLK_SET_RATE_GATE, CCU_DIV_BASIC),
218 CCU_DIV_VAR_INFO(CCU_SYS_TIMER1_CLK, "sys_timer1_clk",
219 "ref_clk", CCU_SYS_TIMER1_BASE, 17,
220 CLK_SET_RATE_GATE, CCU_DIV_BASIC),
221 CCU_DIV_VAR_INFO(CCU_SYS_TIMER2_CLK, "sys_timer2_clk",
222 "ref_clk", CCU_SYS_TIMER2_BASE, 17,
223 CLK_SET_RATE_GATE, CCU_DIV_BASIC),
224 CCU_DIV_VAR_INFO(CCU_SYS_WDT_CLK, "sys_wdt_clk",
225 "eth_clk", CCU_SYS_WDT_BASE, 17,
226 CLK_SET_RATE_GATE, CCU_DIV_SKIP_ONE_TO_THREE)
227};
228
229static struct ccu_div_data *axi_data;
230static struct ccu_div_data *sys_data;
231
232static void ccu_div_set_data(struct ccu_div_data *data)
233{
234 struct device_node *np = data->np;
235
236 if (of_device_is_compatible(device: np, "baikal,bt1-ccu-axi"))
237 axi_data = data;
238 else if (of_device_is_compatible(device: np, "baikal,bt1-ccu-sys"))
239 sys_data = data;
240 else
241 pr_err("Invalid DT node '%s' specified\n", of_node_full_name(np));
242}
243
244static struct ccu_div_data *ccu_div_get_data(struct device_node *np)
245{
246 if (of_device_is_compatible(device: np, "baikal,bt1-ccu-axi"))
247 return axi_data;
248 else if (of_device_is_compatible(device: np, "baikal,bt1-ccu-sys"))
249 return sys_data;
250
251 pr_err("Invalid DT node '%s' specified\n", of_node_full_name(np));
252
253 return NULL;
254}
255
256static struct ccu_div *ccu_div_find_desc(struct ccu_div_data *data,
257 unsigned int clk_id)
258{
259 int idx;
260
261 for (idx = 0; idx < data->divs_num; ++idx) {
262 if (data->divs_info[idx].id == clk_id)
263 return data->divs[idx];
264 }
265
266 return ERR_PTR(error: -EINVAL);
267}
268
269static struct ccu_div_data *ccu_div_create_data(struct device_node *np)
270{
271 struct ccu_div_data *data;
272 int ret;
273
274 data = kzalloc(size: sizeof(*data), GFP_KERNEL);
275 if (!data)
276 return ERR_PTR(error: -ENOMEM);
277
278 data->np = np;
279 if (of_device_is_compatible(device: np, "baikal,bt1-ccu-axi")) {
280 data->divs_num = ARRAY_SIZE(axi_info);
281 data->divs_info = axi_info;
282 } else if (of_device_is_compatible(device: np, "baikal,bt1-ccu-sys")) {
283 data->divs_num = ARRAY_SIZE(sys_info);
284 data->divs_info = sys_info;
285 } else {
286 pr_err("Incompatible DT node '%s' specified\n",
287 of_node_full_name(np));
288 ret = -EINVAL;
289 goto err_kfree_data;
290 }
291
292 data->divs = kcalloc(n: data->divs_num, size: sizeof(*data->divs), GFP_KERNEL);
293 if (!data->divs) {
294 ret = -ENOMEM;
295 goto err_kfree_data;
296 }
297
298 return data;
299
300err_kfree_data:
301 kfree(objp: data);
302
303 return ERR_PTR(error: ret);
304}
305
306static void ccu_div_free_data(struct ccu_div_data *data)
307{
308 kfree(objp: data->divs);
309
310 kfree(objp: data);
311}
312
313static int ccu_div_find_sys_regs(struct ccu_div_data *data)
314{
315 data->sys_regs = syscon_node_to_regmap(np: data->np->parent);
316 if (IS_ERR(ptr: data->sys_regs)) {
317 pr_err("Failed to find syscon regs for '%s'\n",
318 of_node_full_name(data->np));
319 return PTR_ERR(ptr: data->sys_regs);
320 }
321
322 return 0;
323}
324
325static struct clk_hw *ccu_div_of_clk_hw_get(struct of_phandle_args *clkspec,
326 void *priv)
327{
328 struct ccu_div_data *data = priv;
329 struct ccu_div *div;
330 unsigned int clk_id;
331
332 clk_id = clkspec->args[0];
333 div = ccu_div_find_desc(data, clk_id);
334 if (IS_ERR(ptr: div)) {
335 if (div != ERR_PTR(error: -EPROBE_DEFER))
336 pr_info("Invalid clock ID %d specified\n", clk_id);
337
338 return ERR_CAST(ptr: div);
339 }
340
341 return ccu_div_get_clk_hw(div);
342}
343
344static int ccu_div_clk_register(struct ccu_div_data *data, bool defer)
345{
346 int idx, ret;
347
348 for (idx = 0; idx < data->divs_num; ++idx) {
349 const struct ccu_div_info *info = &data->divs_info[idx];
350 struct ccu_div_init_data init = {0};
351
352 if (!!(info->features & CCU_DIV_BASIC) ^ defer) {
353 if (!data->divs[idx])
354 data->divs[idx] = ERR_PTR(error: -EPROBE_DEFER);
355
356 continue;
357 }
358
359 init.id = info->id;
360 init.name = info->name;
361 init.parent_name = info->parent_name;
362 init.np = data->np;
363 init.type = info->type;
364 init.flags = info->flags;
365 init.features = info->features;
366
367 if (init.type == CCU_DIV_VAR) {
368 init.base = info->base;
369 init.sys_regs = data->sys_regs;
370 init.width = info->width;
371 } else if (init.type == CCU_DIV_GATE) {
372 init.base = info->base;
373 init.sys_regs = data->sys_regs;
374 init.divider = info->divider;
375 } else if (init.type == CCU_DIV_BUF) {
376 init.base = info->base;
377 init.sys_regs = data->sys_regs;
378 } else {
379 init.divider = info->divider;
380 }
381
382 data->divs[idx] = ccu_div_hw_register(init: &init);
383 if (IS_ERR(ptr: data->divs[idx])) {
384 ret = PTR_ERR(ptr: data->divs[idx]);
385 pr_err("Couldn't register divider '%s' hw\n",
386 init.name);
387 goto err_hw_unregister;
388 }
389 }
390
391 return 0;
392
393err_hw_unregister:
394 for (--idx; idx >= 0; --idx) {
395 if (!!(data->divs_info[idx].features & CCU_DIV_BASIC) ^ defer)
396 continue;
397
398 ccu_div_hw_unregister(div: data->divs[idx]);
399 }
400
401 return ret;
402}
403
404static void ccu_div_clk_unregister(struct ccu_div_data *data, bool defer)
405{
406 int idx;
407
408 /* Uninstall only the clocks registered on the specfied stage */
409 for (idx = 0; idx < data->divs_num; ++idx) {
410 if (!!(data->divs_info[idx].features & CCU_DIV_BASIC) ^ defer)
411 continue;
412
413 ccu_div_hw_unregister(div: data->divs[idx]);
414 }
415}
416
417static int ccu_div_of_register(struct ccu_div_data *data)
418{
419 int ret;
420
421 ret = of_clk_add_hw_provider(np: data->np, get: ccu_div_of_clk_hw_get, data);
422 if (ret) {
423 pr_err("Couldn't register dividers '%s' clock provider\n",
424 of_node_full_name(data->np));
425 }
426
427 return ret;
428}
429
430static int ccu_div_rst_register(struct ccu_div_data *data)
431{
432 struct ccu_rst_init_data init = {0};
433
434 init.sys_regs = data->sys_regs;
435 init.np = data->np;
436
437 data->rsts = ccu_rst_hw_register(init: &init);
438 if (IS_ERR(ptr: data->rsts)) {
439 pr_err("Couldn't register divider '%s' reset controller\n",
440 of_node_full_name(data->np));
441 return PTR_ERR(ptr: data->rsts);
442 }
443
444 return 0;
445}
446
447static int ccu_div_probe(struct platform_device *pdev)
448{
449 struct ccu_div_data *data;
450 int ret;
451
452 data = ccu_div_get_data(np: dev_of_node(dev: &pdev->dev));
453 if (!data)
454 return -EINVAL;
455
456 ret = ccu_div_clk_register(data, defer: false);
457 if (ret)
458 return ret;
459
460 ret = ccu_div_rst_register(data);
461 if (ret)
462 goto err_clk_unregister;
463
464 return 0;
465
466err_clk_unregister:
467 ccu_div_clk_unregister(data, defer: false);
468
469 return ret;
470}
471
472static const struct of_device_id ccu_div_of_match[] = {
473 { .compatible = "baikal,bt1-ccu-axi" },
474 { .compatible = "baikal,bt1-ccu-sys" },
475 { }
476};
477
478static struct platform_driver ccu_div_driver = {
479 .probe = ccu_div_probe,
480 .driver = {
481 .name = "clk-ccu-div",
482 .of_match_table = ccu_div_of_match,
483 .suppress_bind_attrs = true,
484 },
485};
486builtin_platform_driver(ccu_div_driver);
487
488static __init void ccu_div_init(struct device_node *np)
489{
490 struct ccu_div_data *data;
491 int ret;
492
493 data = ccu_div_create_data(np);
494 if (IS_ERR(ptr: data))
495 return;
496
497 ret = ccu_div_find_sys_regs(data);
498 if (ret)
499 goto err_free_data;
500
501 ret = ccu_div_clk_register(data, defer: true);
502 if (ret)
503 goto err_free_data;
504
505 ret = ccu_div_of_register(data);
506 if (ret)
507 goto err_clk_unregister;
508
509 ccu_div_set_data(data);
510
511 return;
512
513err_clk_unregister:
514 ccu_div_clk_unregister(data, defer: true);
515
516err_free_data:
517 ccu_div_free_data(data);
518}
519CLK_OF_DECLARE_DRIVER(ccu_axi, "baikal,bt1-ccu-axi", ccu_div_init);
520CLK_OF_DECLARE_DRIVER(ccu_sys, "baikal,bt1-ccu-sys", ccu_div_init);
521

source code of linux/drivers/clk/baikal-t1/clk-ccu-div.c