summaryrefslogtreecommitdiff
path: root/drivers/pci/controller/dwc/pcie-uniphier.c
blob: b45ac37542428bb42da0e3566dc3fca5a2ae1b83 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
// SPDX-License-Identifier: GPL-2.0
/*
 * PCIe host controller driver for UniPhier SoCs
 * Copyright 2018 Socionext Inc.
 * Author: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
 */

#include <linux/bitops.h>
#include <linux/bitfield.h>
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/iopoll.h>
#include <linux/irqchip/chained_irq.h>
#include <linux/irqdomain.h>
#include <linux/of_irq.h>
#include <linux/pci.h>
#include <linux/phy/phy.h>
#include <linux/platform_device.h>
#include <linux/reset.h>

#include "pcie-designware.h"

#define PCL_PINCTRL0			0x002c
#define PCL_PERST_PLDN_REGEN		BIT(12)
#define PCL_PERST_NOE_REGEN		BIT(11)
#define PCL_PERST_OUT_REGEN		BIT(8)
#define PCL_PERST_PLDN_REGVAL		BIT(4)
#define PCL_PERST_NOE_REGVAL		BIT(3)
#define PCL_PERST_OUT_REGVAL		BIT(0)

#define PCL_PIPEMON			0x0044
#define PCL_PCLK_ALIVE			BIT(15)

#define PCL_MODE			0x8000
#define PCL_MODE_REGEN			BIT(8)
#define PCL_MODE_REGVAL			BIT(0)

#define PCL_APP_READY_CTRL		0x8008
#define PCL_APP_LTSSM_ENABLE		BIT(0)

#define PCL_APP_PM0			0x8078
#define PCL_SYS_AUX_PWR_DET		BIT(8)

#define PCL_RCV_INT			0x8108
#define PCL_RCV_INT_ALL_ENABLE		GENMASK(20, 17)
#define PCL_CFG_BW_MGT_STATUS		BIT(4)
#define PCL_CFG_LINK_AUTO_BW_STATUS	BIT(3)
#define PCL_CFG_AER_RC_ERR_MSI_STATUS	BIT(2)
#define PCL_CFG_PME_MSI_STATUS		BIT(1)

#define PCL_RCV_INTX			0x810c
#define PCL_RCV_INTX_ALL_ENABLE		GENMASK(19, 16)
#define PCL_RCV_INTX_ALL_MASK		GENMASK(11, 8)
#define PCL_RCV_INTX_MASK_SHIFT		8
#define PCL_RCV_INTX_ALL_STATUS		GENMASK(3, 0)
#define PCL_RCV_INTX_STATUS_SHIFT	0

#define PCL_STATUS_LINK			0x8140
#define PCL_RDLH_LINK_UP		BIT(1)
#define PCL_XMLH_LINK_UP		BIT(0)

struct uniphier_pcie {
	struct dw_pcie pci;
	void __iomem *base;
	struct clk *clk;
	struct reset_control *rst;
	struct phy *phy;
	struct irq_domain *legacy_irq_domain;
};

#define to_uniphier_pcie(x)	dev_get_drvdata((x)->dev)

static void uniphier_pcie_ltssm_enable(struct uniphier_pcie *pcie,
				       bool enable)
{
	u32 val;

	val = readl(pcie->base + PCL_APP_READY_CTRL);
	if (enable)
		val |= PCL_APP_LTSSM_ENABLE;
	else
		val &= ~PCL_APP_LTSSM_ENABLE;
	writel(val, pcie->base + PCL_APP_READY_CTRL);
}

static void uniphier_pcie_init_rc(struct uniphier_pcie *pcie)
{
	u32 val;

	/* set RC MODE */
	val = readl(pcie->base + PCL_MODE);
	val |= PCL_MODE_REGEN;
	val &= ~PCL_MODE_REGVAL;
	writel(val, pcie->base + PCL_MODE);

	/* use auxiliary power detection */
	val = readl(pcie->base + PCL_APP_PM0);
	val |= PCL_SYS_AUX_PWR_DET;
	writel(val, pcie->base + PCL_APP_PM0);

	/* assert PERST# */
	val = readl(pcie->base + PCL_PINCTRL0);
	val &= ~(PCL_PERST_NOE_REGVAL | PCL_PERST_OUT_REGVAL
		 | PCL_PERST_PLDN_REGVAL);
	val |= PCL_PERST_NOE_REGEN | PCL_PERST_OUT_REGEN
		| PCL_PERST_PLDN_REGEN;
	writel(val, pcie->base + PCL_PINCTRL0);

	uniphier_pcie_ltssm_enable(pcie, false);

	usleep_range(100000, 200000);

	/* deassert PERST# */
	val = readl(pcie->base + PCL_PINCTRL0);
	val |= PCL_PERST_OUT_REGVAL | PCL_PERST_OUT_REGEN;
	writel(val, pcie->base + PCL_PINCTRL0);
}

static int uniphier_pcie_wait_rc(struct uniphier_pcie *pcie)
{
	u32 status;
	int ret;

	/* wait PIPE clock */
	ret = readl_poll_timeout(pcie->base + PCL_PIPEMON, status,
				 status & PCL_PCLK_ALIVE, 100000, 1000000);
	if (ret) {
		dev_err(pcie->pci.dev,
			"Failed to initialize controller in RC mode\n");
		return ret;
	}

	return 0;
}

static int uniphier_pcie_link_up(struct dw_pcie *pci)
{
	struct uniphier_pcie *pcie = to_uniphier_pcie(pci);
	u32 val, mask;

	val = readl(pcie->base + PCL_STATUS_LINK);
	mask = PCL_RDLH_LINK_UP | PCL_XMLH_LINK_UP;

	return (val & mask) == mask;
}

static int uniphier_pcie_start_link(struct dw_pcie *pci)
{
	struct uniphier_pcie *pcie = to_uniphier_pcie(pci);

	uniphier_pcie_ltssm_enable(pcie, true);

	return 0;
}

static void uniphier_pcie_stop_link(struct dw_pcie *pci)
{
	struct uniphier_pcie *pcie = to_uniphier_pcie(pci);

	uniphier_pcie_ltssm_enable(pcie, false);
}

static void uniphier_pcie_irq_enable(struct uniphier_pcie *pcie)
{
	writel(PCL_RCV_INT_ALL_ENABLE, pcie->base + PCL_RCV_INT);
	writel(PCL_RCV_INTX_ALL_ENABLE, pcie->base + PCL_RCV_INTX);
}


static void uniphier_pcie_irq_mask(struct irq_data *d)
{
	struct pcie_port *pp = irq_data_get_irq_chip_data(d);
	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
	struct uniphier_pcie *pcie = to_uniphier_pcie(pci);
	unsigned long flags;
	u32 val;

	raw_spin_lock_irqsave(&pp->lock, flags);

	val = readl(pcie->base + PCL_RCV_INTX);
	val |= BIT(irqd_to_hwirq(d) + PCL_RCV_INTX_MASK_SHIFT);
	writel(val, pcie->base + PCL_RCV_INTX);

	raw_spin_unlock_irqrestore(&pp->lock, flags);
}

static void uniphier_pcie_irq_unmask(struct irq_data *d)
{
	struct pcie_port *pp = irq_data_get_irq_chip_data(d);
	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
	struct uniphier_pcie *pcie = to_uniphier_pcie(pci);
	unsigned long flags;
	u32 val;

	raw_spin_lock_irqsave(&pp->lock, flags);

	val = readl(pcie->base + PCL_RCV_INTX);
	val &= ~BIT(irqd_to_hwirq(d) + PCL_RCV_INTX_MASK_SHIFT);
	writel(val, pcie->base + PCL_RCV_INTX);

	raw_spin_unlock_irqrestore(&pp->lock, flags);
}

static struct irq_chip uniphier_pcie_irq_chip = {
	.name = "PCI",
	.irq_mask = uniphier_pcie_irq_mask,
	.irq_unmask = uniphier_pcie_irq_unmask,
};

static int uniphier_pcie_intx_map(struct irq_domain *domain, unsigned int irq,
				  irq_hw_number_t hwirq)
{
	irq_set_chip_and_handler(irq, &uniphier_pcie_irq_chip,
				 handle_level_irq);
	irq_set_chip_data(irq, domain->host_data);

	return 0;
}

static const struct irq_domain_ops uniphier_intx_domain_ops = {
	.map = uniphier_pcie_intx_map,
};

static void uniphier_pcie_irq_handler(struct irq_desc *desc)
{
	struct pcie_port *pp = irq_desc_get_handler_data(desc);
	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
	struct uniphier_pcie *pcie = to_uniphier_pcie(pci);
	struct irq_chip *chip = irq_desc_get_chip(desc);
	unsigned long reg;
	u32 val, bit;

	/* INT for debug */
	val = readl(pcie->base + PCL_RCV_INT);

	if (val & PCL_CFG_BW_MGT_STATUS)
		dev_dbg(pci->dev, "Link Bandwidth Management Event\n");
	if (val & PCL_CFG_LINK_AUTO_BW_STATUS)
		dev_dbg(pci->dev, "Link Autonomous Bandwidth Event\n");
	if (val & PCL_CFG_AER_RC_ERR_MSI_STATUS)
		dev_dbg(pci->dev, "Root Error\n");
	if (val & PCL_CFG_PME_MSI_STATUS)
		dev_dbg(pci->dev, "PME Interrupt\n");

	writel(val, pcie->base + PCL_RCV_INT);

	/* INTx */
	chained_irq_enter(chip, desc);

	val = readl(pcie->base + PCL_RCV_INTX);
	reg = FIELD_GET(PCL_RCV_INTX_ALL_STATUS, val);

	for_each_set_bit(bit, &reg, PCI_NUM_INTX)
		generic_handle_domain_irq(pcie->legacy_irq_domain, bit);

	chained_irq_exit(chip, desc);
}

static int uniphier_pcie_config_legacy_irq(struct pcie_port *pp)
{
	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
	struct uniphier_pcie *pcie = to_uniphier_pcie(pci);
	struct device_node *np = pci->dev->of_node;
	struct device_node *np_intc;
	int ret = 0;

	np_intc = of_get_child_by_name(np, "legacy-interrupt-controller");
	if (!np_intc) {
		dev_err(pci->dev, "Failed to get legacy-interrupt-controller node\n");
		return -EINVAL;
	}

	pp->irq = irq_of_parse_and_map(np_intc, 0);
	if (!pp->irq) {
		dev_err(pci->dev, "Failed to get an IRQ entry in legacy-interrupt-controller\n");
		ret = -EINVAL;
		goto out_put_node;
	}

	pcie->legacy_irq_domain = irq_domain_add_linear(np_intc, PCI_NUM_INTX,
						&uniphier_intx_domain_ops, pp);
	if (!pcie->legacy_irq_domain) {
		dev_err(pci->dev, "Failed to get INTx domain\n");
		ret = -ENODEV;
		goto out_put_node;
	}

	irq_set_chained_handler_and_data(pp->irq, uniphier_pcie_irq_handler,
					 pp);

out_put_node:
	of_node_put(np_intc);
	return ret;
}

static int uniphier_pcie_host_init(struct pcie_port *pp)
{
	struct dw_pcie *pci = to_dw_pcie_from_pp(pp);
	struct uniphier_pcie *pcie = to_uniphier_pcie(pci);
	int ret;

	ret = uniphier_pcie_config_legacy_irq(pp);
	if (ret)
		return ret;

	uniphier_pcie_irq_enable(pcie);

	return 0;
}

static const struct dw_pcie_host_ops uniphier_pcie_host_ops = {
	.host_init = uniphier_pcie_host_init,
};

static int uniphier_pcie_host_enable(struct uniphier_pcie *pcie)
{
	int ret;

	ret = clk_prepare_enable(pcie->clk);
	if (ret)
		return ret;

	ret = reset_control_deassert(pcie->rst);
	if (ret)
		goto out_clk_disable;

	uniphier_pcie_init_rc(pcie);

	ret = phy_init(pcie->phy);
	if (ret)
		goto out_rst_assert;

	ret = uniphier_pcie_wait_rc(pcie);
	if (ret)
		goto out_phy_exit;

	return 0;

out_phy_exit:
	phy_exit(pcie->phy);
out_rst_assert:
	reset_control_assert(pcie->rst);
out_clk_disable:
	clk_disable_unprepare(pcie->clk);

	return ret;
}

static const struct dw_pcie_ops dw_pcie_ops = {
	.start_link = uniphier_pcie_start_link,
	.stop_link = uniphier_pcie_stop_link,
	.link_up = uniphier_pcie_link_up,
};

static int uniphier_pcie_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct uniphier_pcie *pcie;
	int ret;

	pcie = devm_kzalloc(dev, sizeof(*pcie), GFP_KERNEL);
	if (!pcie)
		return -ENOMEM;

	pcie->pci.dev = dev;
	pcie->pci.ops = &dw_pcie_ops;

	pcie->base = devm_platform_ioremap_resource_byname(pdev, "link");
	if (IS_ERR(pcie->base))
		return PTR_ERR(pcie->base);

	pcie->clk = devm_clk_get(dev, NULL);
	if (IS_ERR(pcie->clk))
		return PTR_ERR(pcie->clk);

	pcie->rst = devm_reset_control_get_shared(dev, NULL);
	if (IS_ERR(pcie->rst))
		return PTR_ERR(pcie->rst);

	pcie->phy = devm_phy_optional_get(dev, "pcie-phy");
	if (IS_ERR(pcie->phy))
		return PTR_ERR(pcie->phy);

	platform_set_drvdata(pdev, pcie);

	ret = uniphier_pcie_host_enable(pcie);
	if (ret)
		return ret;

	pcie->pci.pp.ops = &uniphier_pcie_host_ops;

	return dw_pcie_host_init(&pcie->pci.pp);
}

static const struct of_device_id uniphier_pcie_match[] = {
	{ .compatible = "socionext,uniphier-pcie", },
	{ /* sentinel */ },
};

static struct platform_driver uniphier_pcie_driver = {
	.probe  = uniphier_pcie_probe,
	.driver = {
		.name = "uniphier-pcie",
		.of_match_table = uniphier_pcie_match,
	},
};
builtin_platform_driver(uniphier_pcie_driver);