1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Cortina Systems Gemini SATA bridge add-on to Faraday FTIDE010
4 * Copyright (C) 2017 Linus Walleij <linus.walleij@linaro.org>
5 */
6
7 #include <linux/init.h>
8 #include <linux/module.h>
9 #include <linux/platform_device.h>
10 #include <linux/bitops.h>
11 #include <linux/mfd/syscon.h>
12 #include <linux/regmap.h>
13 #include <linux/delay.h>
14 #include <linux/reset.h>
15 #include <linux/of_address.h>
16 #include <linux/of_device.h>
17 #include <linux/clk.h>
18 #include <linux/io.h>
19 #include <linux/pinctrl/consumer.h>
20 #include "sata_gemini.h"
21
22 #define DRV_NAME "gemini_sata_bridge"
23
24 /**
25 * struct sata_gemini - a state container for a Gemini SATA bridge
26 * @dev: the containing device
27 * @base: remapped I/O memory base
28 * @muxmode: the current muxing mode
29 * @ide_pins: if the device is using the plain IDE interface pins
30 * @sata_bridge: if the device enables the SATA bridge
31 * @sata0_reset: SATA0 reset handler
32 * @sata1_reset: SATA1 reset handler
33 * @sata0_pclk: SATA0 PCLK handler
34 * @sata1_pclk: SATA1 PCLK handler
35 */
36 struct sata_gemini {
37 struct device *dev;
38 void __iomem *base;
39 enum gemini_muxmode muxmode;
40 bool ide_pins;
41 bool sata_bridge;
42 struct reset_control *sata0_reset;
43 struct reset_control *sata1_reset;
44 struct clk *sata0_pclk;
45 struct clk *sata1_pclk;
46 };
47
48 /* Miscellaneous Control Register */
49 #define GEMINI_GLOBAL_MISC_CTRL 0x30
50 /*
51 * Values of IDE IOMUX bits in the misc control register
52 *
53 * Bits 26:24 are "IDE IO Select", which decides what SATA
54 * adapters are connected to which of the two IDE/ATA
55 * controllers in the Gemini. We can connect the two IDE blocks
56 * to one SATA adapter each, both acting as master, or one IDE
57 * blocks to two SATA adapters so the IDE block can act in a
58 * master/slave configuration.
59 *
60 * We also bring out different blocks on the actual IDE
61 * pins (not SATA pins) if (and only if) these are muxed in.
62 *
63 * 111-100 - Reserved
64 * Mode 0: 000 - ata0 master <-> sata0
65 * ata1 master <-> sata1
66 * ata0 slave interface brought out on IDE pads
67 * Mode 1: 001 - ata0 master <-> sata0
68 * ata1 master <-> sata1
69 * ata1 slave interface brought out on IDE pads
70 * Mode 2: 010 - ata1 master <-> sata1
71 * ata1 slave <-> sata0
72 * ata0 master and slave interfaces brought out
73 * on IDE pads
74 * Mode 3: 011 - ata0 master <-> sata0
75 * ata1 slave <-> sata1
76 * ata1 master and slave interfaces brought out
77 * on IDE pads
78 */
79 #define GEMINI_IDE_IOMUX_MASK (7 << 24)
80 #define GEMINI_IDE_IOMUX_MODE0 (0 << 24)
81 #define GEMINI_IDE_IOMUX_MODE1 (1 << 24)
82 #define GEMINI_IDE_IOMUX_MODE2 (2 << 24)
83 #define GEMINI_IDE_IOMUX_MODE3 (3 << 24)
84 #define GEMINI_IDE_IOMUX_SHIFT (24)
85
86 /*
87 * Registers directly controlling the PATA<->SATA adapters
88 */
89 #define GEMINI_SATA_ID 0x00
90 #define GEMINI_SATA_PHY_ID 0x04
91 #define GEMINI_SATA0_STATUS 0x08
92 #define GEMINI_SATA1_STATUS 0x0c
93 #define GEMINI_SATA0_CTRL 0x18
94 #define GEMINI_SATA1_CTRL 0x1c
95
96 #define GEMINI_SATA_STATUS_BIST_DONE BIT(5)
97 #define GEMINI_SATA_STATUS_BIST_OK BIT(4)
98 #define GEMINI_SATA_STATUS_PHY_READY BIT(0)
99
100 #define GEMINI_SATA_CTRL_PHY_BIST_EN BIT(14)
101 #define GEMINI_SATA_CTRL_PHY_FORCE_IDLE BIT(13)
102 #define GEMINI_SATA_CTRL_PHY_FORCE_READY BIT(12)
103 #define GEMINI_SATA_CTRL_PHY_AFE_LOOP_EN BIT(10)
104 #define GEMINI_SATA_CTRL_PHY_DIG_LOOP_EN BIT(9)
105 #define GEMINI_SATA_CTRL_HOTPLUG_DETECT_EN BIT(4)
106 #define GEMINI_SATA_CTRL_ATAPI_EN BIT(3)
107 #define GEMINI_SATA_CTRL_BUS_WITH_20 BIT(2)
108 #define GEMINI_SATA_CTRL_SLAVE_EN BIT(1)
109 #define GEMINI_SATA_CTRL_EN BIT(0)
110
111 /*
112 * There is only ever one instance of this bridge on a system,
113 * so create a singleton so that the FTIDE010 instances can grab
114 * a reference to it.
115 */
116 static struct sata_gemini *sg_singleton;
117
gemini_sata_bridge_get(void)118 struct sata_gemini *gemini_sata_bridge_get(void)
119 {
120 if (sg_singleton)
121 return sg_singleton;
122 return ERR_PTR(-EPROBE_DEFER);
123 }
124 EXPORT_SYMBOL(gemini_sata_bridge_get);
125
gemini_sata_bridge_enabled(struct sata_gemini * sg,bool is_ata1)126 bool gemini_sata_bridge_enabled(struct sata_gemini *sg, bool is_ata1)
127 {
128 if (!sg->sata_bridge)
129 return false;
130 /*
131 * In muxmode 2 and 3 one of the ATA controllers is
132 * actually not connected to any SATA bridge.
133 */
134 if ((sg->muxmode == GEMINI_MUXMODE_2) &&
135 !is_ata1)
136 return false;
137 if ((sg->muxmode == GEMINI_MUXMODE_3) &&
138 is_ata1)
139 return false;
140
141 return true;
142 }
143 EXPORT_SYMBOL(gemini_sata_bridge_enabled);
144
gemini_sata_get_muxmode(struct sata_gemini * sg)145 enum gemini_muxmode gemini_sata_get_muxmode(struct sata_gemini *sg)
146 {
147 return sg->muxmode;
148 }
149 EXPORT_SYMBOL(gemini_sata_get_muxmode);
150
gemini_sata_setup_bridge(struct sata_gemini * sg,unsigned int bridge)151 static int gemini_sata_setup_bridge(struct sata_gemini *sg,
152 unsigned int bridge)
153 {
154 unsigned long timeout = jiffies + (HZ * 1);
155 bool bridge_online;
156 u32 val;
157
158 if (bridge == 0) {
159 val = GEMINI_SATA_CTRL_HOTPLUG_DETECT_EN | GEMINI_SATA_CTRL_EN;
160 /* SATA0 slave mode is only used in muxmode 2 */
161 if (sg->muxmode == GEMINI_MUXMODE_2)
162 val |= GEMINI_SATA_CTRL_SLAVE_EN;
163 writel(val, sg->base + GEMINI_SATA0_CTRL);
164 } else {
165 val = GEMINI_SATA_CTRL_HOTPLUG_DETECT_EN | GEMINI_SATA_CTRL_EN;
166 /* SATA1 slave mode is only used in muxmode 3 */
167 if (sg->muxmode == GEMINI_MUXMODE_3)
168 val |= GEMINI_SATA_CTRL_SLAVE_EN;
169 writel(val, sg->base + GEMINI_SATA1_CTRL);
170 }
171
172 /* Vendor code waits 10 ms here */
173 msleep(10);
174
175 /* Wait for PHY to become ready */
176 do {
177 msleep(100);
178
179 if (bridge == 0)
180 val = readl(sg->base + GEMINI_SATA0_STATUS);
181 else
182 val = readl(sg->base + GEMINI_SATA1_STATUS);
183 if (val & GEMINI_SATA_STATUS_PHY_READY)
184 break;
185 } while (time_before(jiffies, timeout));
186
187 bridge_online = !!(val & GEMINI_SATA_STATUS_PHY_READY);
188
189 dev_info(sg->dev, "SATA%d PHY %s\n", bridge,
190 bridge_online ? "ready" : "not ready");
191
192 return bridge_online ? 0: -ENODEV;
193 }
194
gemini_sata_start_bridge(struct sata_gemini * sg,unsigned int bridge)195 int gemini_sata_start_bridge(struct sata_gemini *sg, unsigned int bridge)
196 {
197 struct clk *pclk;
198 int ret;
199
200 if (bridge == 0)
201 pclk = sg->sata0_pclk;
202 else
203 pclk = sg->sata1_pclk;
204 clk_enable(pclk);
205 msleep(10);
206
207 /* Do not keep clocking a bridge that is not online */
208 ret = gemini_sata_setup_bridge(sg, bridge);
209 if (ret)
210 clk_disable(pclk);
211
212 return ret;
213 }
214 EXPORT_SYMBOL(gemini_sata_start_bridge);
215
gemini_sata_stop_bridge(struct sata_gemini * sg,unsigned int bridge)216 void gemini_sata_stop_bridge(struct sata_gemini *sg, unsigned int bridge)
217 {
218 if (bridge == 0)
219 clk_disable(sg->sata0_pclk);
220 else if (bridge == 1)
221 clk_disable(sg->sata1_pclk);
222 }
223 EXPORT_SYMBOL(gemini_sata_stop_bridge);
224
gemini_sata_reset_bridge(struct sata_gemini * sg,unsigned int bridge)225 int gemini_sata_reset_bridge(struct sata_gemini *sg,
226 unsigned int bridge)
227 {
228 if (bridge == 0)
229 reset_control_reset(sg->sata0_reset);
230 else
231 reset_control_reset(sg->sata1_reset);
232 msleep(10);
233 return gemini_sata_setup_bridge(sg, bridge);
234 }
235 EXPORT_SYMBOL(gemini_sata_reset_bridge);
236
gemini_sata_bridge_init(struct sata_gemini * sg)237 static int gemini_sata_bridge_init(struct sata_gemini *sg)
238 {
239 struct device *dev = sg->dev;
240 u32 sata_id, sata_phy_id;
241 int ret;
242
243 sg->sata0_pclk = devm_clk_get(dev, "SATA0_PCLK");
244 if (IS_ERR(sg->sata0_pclk)) {
245 dev_err(dev, "no SATA0 PCLK");
246 return -ENODEV;
247 }
248 sg->sata1_pclk = devm_clk_get(dev, "SATA1_PCLK");
249 if (IS_ERR(sg->sata1_pclk)) {
250 dev_err(dev, "no SATA1 PCLK");
251 return -ENODEV;
252 }
253
254 ret = clk_prepare_enable(sg->sata0_pclk);
255 if (ret) {
256 pr_err("failed to enable SATA0 PCLK\n");
257 return ret;
258 }
259 ret = clk_prepare_enable(sg->sata1_pclk);
260 if (ret) {
261 pr_err("failed to enable SATA1 PCLK\n");
262 clk_disable_unprepare(sg->sata0_pclk);
263 return ret;
264 }
265
266 sg->sata0_reset = devm_reset_control_get_exclusive(dev, "sata0");
267 if (IS_ERR(sg->sata0_reset)) {
268 dev_err(dev, "no SATA0 reset controller\n");
269 clk_disable_unprepare(sg->sata1_pclk);
270 clk_disable_unprepare(sg->sata0_pclk);
271 return PTR_ERR(sg->sata0_reset);
272 }
273 sg->sata1_reset = devm_reset_control_get_exclusive(dev, "sata1");
274 if (IS_ERR(sg->sata1_reset)) {
275 dev_err(dev, "no SATA1 reset controller\n");
276 clk_disable_unprepare(sg->sata1_pclk);
277 clk_disable_unprepare(sg->sata0_pclk);
278 return PTR_ERR(sg->sata1_reset);
279 }
280
281 sata_id = readl(sg->base + GEMINI_SATA_ID);
282 sata_phy_id = readl(sg->base + GEMINI_SATA_PHY_ID);
283 sg->sata_bridge = true;
284 clk_disable(sg->sata0_pclk);
285 clk_disable(sg->sata1_pclk);
286
287 dev_info(dev, "SATA ID %08x, PHY ID: %08x\n", sata_id, sata_phy_id);
288
289 return 0;
290 }
291
gemini_setup_ide_pins(struct device * dev)292 static int gemini_setup_ide_pins(struct device *dev)
293 {
294 struct pinctrl *p;
295 struct pinctrl_state *ide_state;
296 int ret;
297
298 p = devm_pinctrl_get(dev);
299 if (IS_ERR(p))
300 return PTR_ERR(p);
301
302 ide_state = pinctrl_lookup_state(p, "ide");
303 if (IS_ERR(ide_state))
304 return PTR_ERR(ide_state);
305
306 ret = pinctrl_select_state(p, ide_state);
307 if (ret) {
308 dev_err(dev, "could not select IDE state\n");
309 return ret;
310 }
311
312 return 0;
313 }
314
gemini_sata_probe(struct platform_device * pdev)315 static int gemini_sata_probe(struct platform_device *pdev)
316 {
317 struct device *dev = &pdev->dev;
318 struct device_node *np = dev->of_node;
319 struct sata_gemini *sg;
320 struct regmap *map;
321 struct resource *res;
322 enum gemini_muxmode muxmode;
323 u32 gmode;
324 u32 gmask;
325 int ret;
326
327 sg = devm_kzalloc(dev, sizeof(*sg), GFP_KERNEL);
328 if (!sg)
329 return -ENOMEM;
330 sg->dev = dev;
331
332 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
333 if (!res)
334 return -ENODEV;
335
336 sg->base = devm_ioremap_resource(dev, res);
337 if (IS_ERR(sg->base))
338 return PTR_ERR(sg->base);
339
340 map = syscon_regmap_lookup_by_phandle(np, "syscon");
341 if (IS_ERR(map)) {
342 dev_err(dev, "no global syscon\n");
343 return PTR_ERR(map);
344 }
345
346 /* Set up the SATA bridge if need be */
347 if (of_property_read_bool(np, "cortina,gemini-enable-sata-bridge")) {
348 ret = gemini_sata_bridge_init(sg);
349 if (ret)
350 return ret;
351 }
352
353 if (of_property_read_bool(np, "cortina,gemini-enable-ide-pins"))
354 sg->ide_pins = true;
355
356 if (!sg->sata_bridge && !sg->ide_pins) {
357 dev_err(dev, "neither SATA bridge or IDE output enabled\n");
358 ret = -EINVAL;
359 goto out_unprep_clk;
360 }
361
362 ret = of_property_read_u32(np, "cortina,gemini-ata-muxmode", &muxmode);
363 if (ret) {
364 dev_err(dev, "could not parse ATA muxmode\n");
365 goto out_unprep_clk;
366 }
367 if (muxmode > GEMINI_MUXMODE_3) {
368 dev_err(dev, "illegal muxmode %d\n", muxmode);
369 ret = -EINVAL;
370 goto out_unprep_clk;
371 }
372 sg->muxmode = muxmode;
373 gmask = GEMINI_IDE_IOMUX_MASK;
374 gmode = (muxmode << GEMINI_IDE_IOMUX_SHIFT);
375
376 ret = regmap_update_bits(map, GEMINI_GLOBAL_MISC_CTRL, gmask, gmode);
377 if (ret) {
378 dev_err(dev, "unable to set up IDE muxing\n");
379 ret = -ENODEV;
380 goto out_unprep_clk;
381 }
382
383 /*
384 * Route out the IDE pins if desired.
385 * This is done by looking up a special pin control state called
386 * "ide" that will route out the IDE pins.
387 */
388 if (sg->ide_pins) {
389 ret = gemini_setup_ide_pins(dev);
390 if (ret)
391 return ret;
392 }
393
394 dev_info(dev, "set up the Gemini IDE/SATA nexus\n");
395 platform_set_drvdata(pdev, sg);
396 sg_singleton = sg;
397
398 return 0;
399
400 out_unprep_clk:
401 if (sg->sata_bridge) {
402 clk_unprepare(sg->sata1_pclk);
403 clk_unprepare(sg->sata0_pclk);
404 }
405 return ret;
406 }
407
gemini_sata_remove(struct platform_device * pdev)408 static int gemini_sata_remove(struct platform_device *pdev)
409 {
410 struct sata_gemini *sg = platform_get_drvdata(pdev);
411
412 if (sg->sata_bridge) {
413 clk_unprepare(sg->sata1_pclk);
414 clk_unprepare(sg->sata0_pclk);
415 }
416 sg_singleton = NULL;
417
418 return 0;
419 }
420
421 static const struct of_device_id gemini_sata_of_match[] = {
422 {
423 .compatible = "cortina,gemini-sata-bridge",
424 },
425 {},
426 };
427
428 static struct platform_driver gemini_sata_driver = {
429 .driver = {
430 .name = DRV_NAME,
431 .of_match_table = of_match_ptr(gemini_sata_of_match),
432 },
433 .probe = gemini_sata_probe,
434 .remove = gemini_sata_remove,
435 };
436 module_platform_driver(gemini_sata_driver);
437
438 MODULE_AUTHOR("Linus Walleij <linus.walleij@linaro.org>");
439 MODULE_LICENSE("GPL");
440 MODULE_ALIAS("platform:" DRV_NAME);
441