xref: /openbmc/linux/drivers/ata/ahci_dwc.c (revision 9aa2cba7)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * DWC AHCI SATA Platform driver
4  *
5  * Copyright (C) 2021 BAIKAL ELECTRONICS, JSC
6  */
7 
8 #include <linux/ahci_platform.h>
9 #include <linux/bitfield.h>
10 #include <linux/bits.h>
11 #include <linux/clk.h>
12 #include <linux/device.h>
13 #include <linux/kernel.h>
14 #include <linux/libata.h>
15 #include <linux/log2.h>
16 #include <linux/mfd/syscon.h>
17 #include <linux/module.h>
18 #include <linux/of.h>
19 #include <linux/platform_device.h>
20 #include <linux/pm.h>
21 #include <linux/regmap.h>
22 
23 #include "ahci.h"
24 
25 #define DRV_NAME "ahci-dwc"
26 
27 #define AHCI_DWC_FBS_PMPN_MAX		15
28 
29 /* DWC AHCI SATA controller specific registers */
30 #define AHCI_DWC_HOST_OOBR		0xbc
31 #define AHCI_DWC_HOST_OOB_WE		BIT(31)
32 #define AHCI_DWC_HOST_CWMIN_MASK	GENMASK(30, 24)
33 #define AHCI_DWC_HOST_CWMAX_MASK	GENMASK(23, 16)
34 #define AHCI_DWC_HOST_CIMIN_MASK	GENMASK(15, 8)
35 #define AHCI_DWC_HOST_CIMAX_MASK	GENMASK(7, 0)
36 
37 #define AHCI_DWC_HOST_GPCR		0xd0
38 #define AHCI_DWC_HOST_GPSR		0xd4
39 
40 #define AHCI_DWC_HOST_TIMER1MS		0xe0
41 #define AHCI_DWC_HOST_TIMV_MASK		GENMASK(19, 0)
42 
43 #define AHCI_DWC_HOST_GPARAM1R		0xe8
44 #define AHCI_DWC_HOST_ALIGN_M		BIT(31)
45 #define AHCI_DWC_HOST_RX_BUFFER		BIT(30)
46 #define AHCI_DWC_HOST_PHY_DATA_MASK	GENMASK(29, 28)
47 #define AHCI_DWC_HOST_PHY_RST		BIT(27)
48 #define AHCI_DWC_HOST_PHY_CTRL_MASK	GENMASK(26, 21)
49 #define AHCI_DWC_HOST_PHY_STAT_MASK	GENMASK(20, 15)
50 #define AHCI_DWC_HOST_LATCH_M		BIT(14)
51 #define AHCI_DWC_HOST_PHY_TYPE_MASK	GENMASK(13, 11)
52 #define AHCI_DWC_HOST_RET_ERR		BIT(10)
53 #define AHCI_DWC_HOST_AHB_ENDIAN_MASK	GENMASK(9, 8)
54 #define AHCI_DWC_HOST_S_HADDR		BIT(7)
55 #define AHCI_DWC_HOST_M_HADDR		BIT(6)
56 #define AHCI_DWC_HOST_S_HDATA_MASK	GENMASK(5, 3)
57 #define AHCI_DWC_HOST_M_HDATA_MASK	GENMASK(2, 0)
58 
59 #define AHCI_DWC_HOST_GPARAM2R		0xec
60 #define AHCI_DWC_HOST_FBS_MEM_S		BIT(19)
61 #define AHCI_DWC_HOST_FBS_PMPN_MASK	GENMASK(17, 16)
62 #define AHCI_DWC_HOST_FBS_SUP		BIT(15)
63 #define AHCI_DWC_HOST_DEV_CP		BIT(14)
64 #define AHCI_DWC_HOST_DEV_MP		BIT(13)
65 #define AHCI_DWC_HOST_ENCODE_M		BIT(12)
66 #define AHCI_DWC_HOST_RXOOB_CLK_M	BIT(11)
67 #define AHCI_DWC_HOST_RXOOB_M		BIT(10)
68 #define AHCI_DWC_HOST_TXOOB_M		BIT(9)
69 #define AHCI_DWC_HOST_RXOOB_M		BIT(10)
70 #define AHCI_DWC_HOST_RXOOB_CLK_MASK	GENMASK(8, 0)
71 
72 #define AHCI_DWC_HOST_PPARAMR		0xf0
73 #define AHCI_DWC_HOST_TX_MEM_M		BIT(11)
74 #define AHCI_DWC_HOST_TX_MEM_S		BIT(10)
75 #define AHCI_DWC_HOST_RX_MEM_M		BIT(9)
76 #define AHCI_DWC_HOST_RX_MEM_S		BIT(8)
77 #define AHCI_DWC_HOST_TXFIFO_DEPTH	GENMASK(7, 4)
78 #define AHCI_DWC_HOST_RXFIFO_DEPTH	GENMASK(3, 0)
79 
80 #define AHCI_DWC_HOST_TESTR		0xf4
81 #define AHCI_DWC_HOST_PSEL_MASK		GENMASK(18, 16)
82 #define AHCI_DWC_HOST_TEST_IF		BIT(0)
83 
84 #define AHCI_DWC_HOST_VERSIONR		0xf8
85 #define AHCI_DWC_HOST_IDR		0xfc
86 
87 #define AHCI_DWC_PORT_DMACR		0x70
88 #define AHCI_DWC_PORT_RXABL_MASK	GENMASK(15, 12)
89 #define AHCI_DWC_PORT_TXABL_MASK	GENMASK(11, 8)
90 #define AHCI_DWC_PORT_RXTS_MASK		GENMASK(7, 4)
91 #define AHCI_DWC_PORT_TXTS_MASK		GENMASK(3, 0)
92 #define AHCI_DWC_PORT_PHYCR		0x74
93 #define AHCI_DWC_PORT_PHYSR		0x78
94 
95 /* Baikal-T1 AHCI SATA specific registers */
96 #define AHCI_BT1_HOST_PHYCR		AHCI_DWC_HOST_GPCR
97 #define AHCI_BT1_HOST_MPLM_MASK		GENMASK(29, 23)
98 #define AHCI_BT1_HOST_LOSDT_MASK	GENMASK(22, 20)
99 #define AHCI_BT1_HOST_CRR		BIT(19)
100 #define AHCI_BT1_HOST_CRW		BIT(18)
101 #define AHCI_BT1_HOST_CRCD		BIT(17)
102 #define AHCI_BT1_HOST_CRCA		BIT(16)
103 #define AHCI_BT1_HOST_CRDI_MASK		GENMASK(15, 0)
104 
105 #define AHCI_BT1_HOST_PHYSR		AHCI_DWC_HOST_GPSR
106 #define AHCI_BT1_HOST_CRA		BIT(16)
107 #define AHCI_BT1_HOST_CRDO_MASK		GENMASK(15, 0)
108 
109 struct ahci_dwc_plat_data {
110 	unsigned int pflags;
111 	unsigned int hflags;
112 	int (*init)(struct ahci_host_priv *hpriv);
113 	int (*reinit)(struct ahci_host_priv *hpriv);
114 	void (*clear)(struct ahci_host_priv *hpriv);
115 };
116 
117 struct ahci_dwc_host_priv {
118 	const struct ahci_dwc_plat_data *pdata;
119 	struct platform_device *pdev;
120 
121 	u32 timv;
122 	u32 dmacr[AHCI_MAX_PORTS];
123 };
124 
125 static int ahci_bt1_init(struct ahci_host_priv *hpriv)
126 {
127 	struct ahci_dwc_host_priv *dpriv = hpriv->plat_data;
128 	int ret;
129 
130 	/* APB, application and reference clocks are required */
131 	if (!ahci_platform_find_clk(hpriv, "pclk") ||
132 	    !ahci_platform_find_clk(hpriv, "aclk") ||
133 	    !ahci_platform_find_clk(hpriv, "ref")) {
134 		dev_err(&dpriv->pdev->dev, "No system clocks specified\n");
135 		return -EINVAL;
136 	}
137 
138 	/*
139 	 * Fully reset the SATA AXI and ref clocks domain to ensure the state
140 	 * machine is working from scratch especially if the reference clocks
141 	 * source has been changed.
142 	 */
143 	ret = ahci_platform_assert_rsts(hpriv);
144 	if (ret) {
145 		dev_err(&dpriv->pdev->dev, "Couldn't assert the resets\n");
146 		return ret;
147 	}
148 
149 	ret = ahci_platform_deassert_rsts(hpriv);
150 	if (ret) {
151 		dev_err(&dpriv->pdev->dev, "Couldn't de-assert the resets\n");
152 		return ret;
153 	}
154 
155 	return 0;
156 }
157 
158 static struct ahci_host_priv *ahci_dwc_get_resources(struct platform_device *pdev)
159 {
160 	struct ahci_dwc_host_priv *dpriv;
161 	struct ahci_host_priv *hpriv;
162 
163 	dpriv = devm_kzalloc(&pdev->dev, sizeof(*dpriv), GFP_KERNEL);
164 	if (!dpriv)
165 		return ERR_PTR(-ENOMEM);
166 
167 	dpriv->pdev = pdev;
168 	dpriv->pdata = device_get_match_data(&pdev->dev);
169 	if (!dpriv->pdata)
170 		return ERR_PTR(-EINVAL);
171 
172 	hpriv = ahci_platform_get_resources(pdev, dpriv->pdata->pflags);
173 	if (IS_ERR(hpriv))
174 		return hpriv;
175 
176 	hpriv->flags |= dpriv->pdata->hflags;
177 	hpriv->plat_data = (void *)dpriv;
178 
179 	return hpriv;
180 }
181 
182 static void ahci_dwc_check_cap(struct ahci_host_priv *hpriv)
183 {
184 	unsigned long port_map = hpriv->saved_port_map | hpriv->mask_port_map;
185 	struct ahci_dwc_host_priv *dpriv = hpriv->plat_data;
186 	bool dev_mp, dev_cp, fbs_sup;
187 	unsigned int fbs_pmp;
188 	u32 param;
189 	int i;
190 
191 	param = readl(hpriv->mmio + AHCI_DWC_HOST_GPARAM2R);
192 	dev_mp = !!(param & AHCI_DWC_HOST_DEV_MP);
193 	dev_cp = !!(param & AHCI_DWC_HOST_DEV_CP);
194 	fbs_sup = !!(param & AHCI_DWC_HOST_FBS_SUP);
195 	fbs_pmp = 5 * FIELD_GET(AHCI_DWC_HOST_FBS_PMPN_MASK, param);
196 
197 	if (!dev_mp && hpriv->saved_cap & HOST_CAP_MPS) {
198 		dev_warn(&dpriv->pdev->dev, "MPS is unsupported\n");
199 		hpriv->saved_cap &= ~HOST_CAP_MPS;
200 	}
201 
202 
203 	if (fbs_sup && fbs_pmp < AHCI_DWC_FBS_PMPN_MAX) {
204 		dev_warn(&dpriv->pdev->dev, "PMPn is limited up to %u ports\n",
205 			 fbs_pmp);
206 	}
207 
208 	for_each_set_bit(i, &port_map, AHCI_MAX_PORTS) {
209 		if (!dev_mp && hpriv->saved_port_cap[i] & PORT_CMD_MPSP) {
210 			dev_warn(&dpriv->pdev->dev, "MPS incapable port %d\n", i);
211 			hpriv->saved_port_cap[i] &= ~PORT_CMD_MPSP;
212 		}
213 
214 		if (!dev_cp && hpriv->saved_port_cap[i] & PORT_CMD_CPD) {
215 			dev_warn(&dpriv->pdev->dev, "CPD incapable port %d\n", i);
216 			hpriv->saved_port_cap[i] &= ~PORT_CMD_CPD;
217 		}
218 
219 		if (!fbs_sup && hpriv->saved_port_cap[i] & PORT_CMD_FBSCP) {
220 			dev_warn(&dpriv->pdev->dev, "FBS incapable port %d\n", i);
221 			hpriv->saved_port_cap[i] &= ~PORT_CMD_FBSCP;
222 		}
223 	}
224 }
225 
226 static void ahci_dwc_init_timer(struct ahci_host_priv *hpriv)
227 {
228 	struct ahci_dwc_host_priv *dpriv = hpriv->plat_data;
229 	unsigned long rate;
230 	struct clk *aclk;
231 	u32 cap, cap2;
232 
233 	/* 1ms tick is generated only for the CCC or DevSleep features */
234 	cap = readl(hpriv->mmio + HOST_CAP);
235 	cap2 = readl(hpriv->mmio + HOST_CAP2);
236 	if (!(cap & HOST_CAP_CCC) && !(cap2 & HOST_CAP2_SDS))
237 		return;
238 
239 	/*
240 	 * Tick is generated based on the AXI/AHB application clocks signal
241 	 * so we need to be sure in the clock we are going to use.
242 	 */
243 	aclk = ahci_platform_find_clk(hpriv, "aclk");
244 	if (!aclk)
245 		return;
246 
247 	/* 1ms timer interval is set as TIMV = AMBA_FREQ[MHZ] * 1000 */
248 	dpriv->timv = readl(hpriv->mmio + AHCI_DWC_HOST_TIMER1MS);
249 	dpriv->timv = FIELD_GET(AHCI_DWC_HOST_TIMV_MASK, dpriv->timv);
250 	rate = clk_get_rate(aclk) / 1000UL;
251 	if (rate == dpriv->timv)
252 		return;
253 
254 	dev_info(&dpriv->pdev->dev, "Update CCC/DevSlp timer for Fapp %lu MHz\n",
255 		 rate / 1000UL);
256 	dpriv->timv = FIELD_PREP(AHCI_DWC_HOST_TIMV_MASK, rate);
257 	writel(dpriv->timv, hpriv->mmio + AHCI_DWC_HOST_TIMER1MS);
258 }
259 
260 static int ahci_dwc_init_dmacr(struct ahci_host_priv *hpriv)
261 {
262 	struct ahci_dwc_host_priv *dpriv = hpriv->plat_data;
263 	struct device_node *child;
264 	void __iomem *port_mmio;
265 	u32 port, dmacr, ts;
266 
267 	/*
268 	 * Update the DMA Tx/Rx transaction sizes in accordance with the
269 	 * platform setup. Note values exceeding maximal or minimal limits will
270 	 * be automatically clamped. Also note the register isn't affected by
271 	 * the HBA global reset so we can freely initialize it once until the
272 	 * next system reset.
273 	 */
274 	for_each_child_of_node(dpriv->pdev->dev.of_node, child) {
275 		if (!of_device_is_available(child))
276 			continue;
277 
278 		if (of_property_read_u32(child, "reg", &port)) {
279 			of_node_put(child);
280 			return -EINVAL;
281 		}
282 
283 		port_mmio = __ahci_port_base(hpriv, port);
284 		dmacr = readl(port_mmio + AHCI_DWC_PORT_DMACR);
285 
286 		if (!of_property_read_u32(child, "snps,tx-ts-max", &ts)) {
287 			ts = ilog2(ts);
288 			dmacr &= ~AHCI_DWC_PORT_TXTS_MASK;
289 			dmacr |= FIELD_PREP(AHCI_DWC_PORT_TXTS_MASK, ts);
290 		}
291 
292 		if (!of_property_read_u32(child, "snps,rx-ts-max", &ts)) {
293 			ts = ilog2(ts);
294 			dmacr &= ~AHCI_DWC_PORT_RXTS_MASK;
295 			dmacr |= FIELD_PREP(AHCI_DWC_PORT_RXTS_MASK, ts);
296 		}
297 
298 		writel(dmacr, port_mmio + AHCI_DWC_PORT_DMACR);
299 		dpriv->dmacr[port] = dmacr;
300 	}
301 
302 	return 0;
303 }
304 
305 static int ahci_dwc_init_host(struct ahci_host_priv *hpriv)
306 {
307 	struct ahci_dwc_host_priv *dpriv = hpriv->plat_data;
308 	int rc;
309 
310 	rc = ahci_platform_enable_resources(hpriv);
311 	if (rc)
312 		return rc;
313 
314 	if (dpriv->pdata->init) {
315 		rc = dpriv->pdata->init(hpriv);
316 		if (rc)
317 			goto err_disable_resources;
318 	}
319 
320 	ahci_dwc_check_cap(hpriv);
321 
322 	ahci_dwc_init_timer(hpriv);
323 
324 	rc = ahci_dwc_init_dmacr(hpriv);
325 	if (rc)
326 		goto err_clear_platform;
327 
328 	return 0;
329 
330 err_clear_platform:
331 	if (dpriv->pdata->clear)
332 		dpriv->pdata->clear(hpriv);
333 
334 err_disable_resources:
335 	ahci_platform_disable_resources(hpriv);
336 
337 	return rc;
338 }
339 
340 static int ahci_dwc_reinit_host(struct ahci_host_priv *hpriv)
341 {
342 	struct ahci_dwc_host_priv *dpriv = hpriv->plat_data;
343 	unsigned long port_map = hpriv->port_map;
344 	void __iomem *port_mmio;
345 	int i, rc;
346 
347 	rc = ahci_platform_enable_resources(hpriv);
348 	if (rc)
349 		return rc;
350 
351 	if (dpriv->pdata->reinit) {
352 		rc = dpriv->pdata->reinit(hpriv);
353 		if (rc)
354 			goto err_disable_resources;
355 	}
356 
357 	writel(dpriv->timv, hpriv->mmio + AHCI_DWC_HOST_TIMER1MS);
358 
359 	for_each_set_bit(i, &port_map, AHCI_MAX_PORTS) {
360 		port_mmio = __ahci_port_base(hpriv, i);
361 		writel(dpriv->dmacr[i], port_mmio + AHCI_DWC_PORT_DMACR);
362 	}
363 
364 	return 0;
365 
366 err_disable_resources:
367 	ahci_platform_disable_resources(hpriv);
368 
369 	return rc;
370 }
371 
372 static void ahci_dwc_clear_host(struct ahci_host_priv *hpriv)
373 {
374 	struct ahci_dwc_host_priv *dpriv = hpriv->plat_data;
375 
376 	if (dpriv->pdata->clear)
377 		dpriv->pdata->clear(hpriv);
378 
379 	ahci_platform_disable_resources(hpriv);
380 }
381 
382 static void ahci_dwc_stop_host(struct ata_host *host)
383 {
384 	struct ahci_host_priv *hpriv = host->private_data;
385 
386 	ahci_dwc_clear_host(hpriv);
387 }
388 
389 static struct ata_port_operations ahci_dwc_port_ops = {
390 	.inherits	= &ahci_platform_ops,
391 	.host_stop	= ahci_dwc_stop_host,
392 };
393 
394 static const struct ata_port_info ahci_dwc_port_info = {
395 	.flags		= AHCI_FLAG_COMMON,
396 	.pio_mask	= ATA_PIO4,
397 	.udma_mask	= ATA_UDMA6,
398 	.port_ops	= &ahci_dwc_port_ops,
399 };
400 
401 static const struct scsi_host_template ahci_dwc_scsi_info = {
402 	AHCI_SHT(DRV_NAME),
403 };
404 
405 static int ahci_dwc_probe(struct platform_device *pdev)
406 {
407 	struct ahci_host_priv *hpriv;
408 	int rc;
409 
410 	hpriv = ahci_dwc_get_resources(pdev);
411 	if (IS_ERR(hpriv))
412 		return PTR_ERR(hpriv);
413 
414 	rc = ahci_dwc_init_host(hpriv);
415 	if (rc)
416 		return rc;
417 
418 	rc = ahci_platform_init_host(pdev, hpriv, &ahci_dwc_port_info,
419 				     &ahci_dwc_scsi_info);
420 	if (rc)
421 		goto err_clear_host;
422 
423 	return 0;
424 
425 err_clear_host:
426 	ahci_dwc_clear_host(hpriv);
427 
428 	return rc;
429 }
430 
431 static int ahci_dwc_suspend(struct device *dev)
432 {
433 	struct ata_host *host = dev_get_drvdata(dev);
434 	struct ahci_host_priv *hpriv = host->private_data;
435 	int rc;
436 
437 	rc = ahci_platform_suspend_host(dev);
438 	if (rc)
439 		return rc;
440 
441 	ahci_dwc_clear_host(hpriv);
442 
443 	return 0;
444 }
445 
446 static int ahci_dwc_resume(struct device *dev)
447 {
448 	struct ata_host *host = dev_get_drvdata(dev);
449 	struct ahci_host_priv *hpriv = host->private_data;
450 	int rc;
451 
452 	rc = ahci_dwc_reinit_host(hpriv);
453 	if (rc)
454 		return rc;
455 
456 	return ahci_platform_resume_host(dev);
457 }
458 
459 static DEFINE_SIMPLE_DEV_PM_OPS(ahci_dwc_pm_ops, ahci_dwc_suspend,
460 				ahci_dwc_resume);
461 
462 static struct ahci_dwc_plat_data ahci_dwc_plat = {
463 	.pflags = AHCI_PLATFORM_GET_RESETS,
464 };
465 
466 static struct ahci_dwc_plat_data ahci_bt1_plat = {
467 	.pflags = AHCI_PLATFORM_GET_RESETS | AHCI_PLATFORM_RST_TRIGGER,
468 	.init = ahci_bt1_init,
469 };
470 
471 static const struct of_device_id ahci_dwc_of_match[] = {
472 	{ .compatible = "snps,dwc-ahci", &ahci_dwc_plat },
473 	{ .compatible = "snps,spear-ahci", &ahci_dwc_plat },
474 	{ .compatible = "baikal,bt1-ahci", &ahci_bt1_plat },
475 	{},
476 };
477 MODULE_DEVICE_TABLE(of, ahci_dwc_of_match);
478 
479 static struct platform_driver ahci_dwc_driver = {
480 	.probe = ahci_dwc_probe,
481 	.remove_new = ata_platform_remove_one,
482 	.shutdown = ahci_platform_shutdown,
483 	.driver = {
484 		.name = DRV_NAME,
485 		.of_match_table = ahci_dwc_of_match,
486 		.pm = &ahci_dwc_pm_ops,
487 	},
488 };
489 module_platform_driver(ahci_dwc_driver);
490 
491 MODULE_DESCRIPTION("DWC AHCI SATA platform driver");
492 MODULE_AUTHOR("Serge Semin <Sergey.Semin@baikalelectronics.ru>");
493 MODULE_LICENSE("GPL");
494