summaryrefslogtreecommitdiffstats
path: root/drivers/pci/host/pcie-spear13xx.c
blob: a6cd8233e8c08c8fee6e1df3a1a7d40fdc2250a8 (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
/*
 * PCIe host controller driver for ST Microelectronics SPEAr13xx SoCs
 *
 * SPEAr13xx PCIe Glue Layer Source Code
 *
 * Copyright (C) 2010-2014 ST Microelectronics
 * Pratyush Anand <pratyush.anand@gmail.com>
 * Mohit Kumar <mohit.kumar.dhaka@gmail.com>
 *
 * This file is licensed under the terms of the GNU General Public
 * License version 2. This program is licensed "as is" without any
 * warranty of any kind, whether express or implied.
 */

#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/pci.h>
#include <linux/phy/phy.h>
#include <linux/platform_device.h>
#include <linux/resource.h>

#include "pcie-designware.h"

struct spear13xx_pcie {
	void __iomem		*app_base;
	struct phy		*phy;
	struct clk		*clk;
	struct pcie_port	pp;
	bool			is_gen1;
};

struct pcie_app_reg {
	u32	app_ctrl_0;		/* cr0 */
	u32	app_ctrl_1;		/* cr1 */
	u32	app_status_0;		/* cr2 */
	u32	app_status_1;		/* cr3 */
	u32	msg_status;		/* cr4 */
	u32	msg_payload;		/* cr5 */
	u32	int_sts;		/* cr6 */
	u32	int_clr;		/* cr7 */
	u32	int_mask;		/* cr8 */
	u32	mst_bmisc;		/* cr9 */
	u32	phy_ctrl;		/* cr10 */
	u32	phy_status;		/* cr11 */
	u32	cxpl_debug_info_0;	/* cr12 */
	u32	cxpl_debug_info_1;	/* cr13 */
	u32	ven_msg_ctrl_0;		/* cr14 */
	u32	ven_msg_ctrl_1;		/* cr15 */
	u32	ven_msg_data_0;		/* cr16 */
	u32	ven_msg_data_1;		/* cr17 */
	u32	ven_msi_0;		/* cr18 */
	u32	ven_msi_1;		/* cr19 */
	u32	mst_rmisc;		/* cr20 */
};

/* CR0 ID */
#define RX_LANE_FLIP_EN_ID			0
#define TX_LANE_FLIP_EN_ID			1
#define SYS_AUX_PWR_DET_ID			2
#define APP_LTSSM_ENABLE_ID			3
#define SYS_ATTEN_BUTTON_PRESSED_ID		4
#define SYS_MRL_SENSOR_STATE_ID			5
#define SYS_PWR_FAULT_DET_ID			6
#define SYS_MRL_SENSOR_CHGED_ID			7
#define SYS_PRE_DET_CHGED_ID			8
#define SYS_CMD_CPLED_INT_ID			9
#define APP_INIT_RST_0_ID			11
#define APP_REQ_ENTR_L1_ID			12
#define APP_READY_ENTR_L23_ID			13
#define APP_REQ_EXIT_L1_ID			14
#define DEVICE_TYPE_EP				(0 << 25)
#define DEVICE_TYPE_LEP				(1 << 25)
#define DEVICE_TYPE_RC				(4 << 25)
#define SYS_INT_ID				29
#define MISCTRL_EN_ID				30
#define REG_TRANSLATION_ENABLE			31

/* CR1 ID */
#define APPS_PM_XMT_TURNOFF_ID			2
#define APPS_PM_XMT_PME_ID			5

/* CR3 ID */
#define XMLH_LTSSM_STATE_DETECT_QUIET		0x00
#define XMLH_LTSSM_STATE_DETECT_ACT		0x01
#define XMLH_LTSSM_STATE_POLL_ACTIVE		0x02
#define XMLH_LTSSM_STATE_POLL_COMPLIANCE	0x03
#define XMLH_LTSSM_STATE_POLL_CONFIG		0x04
#define XMLH_LTSSM_STATE_PRE_DETECT_QUIET	0x05
#define XMLH_LTSSM_STATE_DETECT_WAIT		0x06
#define XMLH_LTSSM_STATE_CFG_LINKWD_START	0x07
#define XMLH_LTSSM_STATE_CFG_LINKWD_ACEPT	0x08
#define XMLH_LTSSM_STATE_CFG_LANENUM_WAIT	0x09
#define XMLH_LTSSM_STATE_CFG_LANENUM_ACEPT	0x0A
#define XMLH_LTSSM_STATE_CFG_COMPLETE		0x0B
#define XMLH_LTSSM_STATE_CFG_IDLE		0x0C
#define XMLH_LTSSM_STATE_RCVRY_LOCK		0x0D
#define XMLH_LTSSM_STATE_RCVRY_SPEED		0x0E
#define XMLH_LTSSM_STATE_RCVRY_RCVRCFG		0x0F
#define XMLH_LTSSM_STATE_RCVRY_IDLE		0x10
#define XMLH_LTSSM_STATE_L0			0x11
#define XMLH_LTSSM_STATE_L0S			0x12
#define XMLH_LTSSM_STATE_L123_SEND_EIDLE	0x13
#define XMLH_LTSSM_STATE_L1_IDLE		0x14
#define XMLH_LTSSM_STATE_L2_IDLE		0x15
#define XMLH_LTSSM_STATE_L2_WAKE		0x16
#define XMLH_LTSSM_STATE_DISABLED_ENTRY		0x17
#define XMLH_LTSSM_STATE_DISABLED_IDLE		0x18
#define XMLH_LTSSM_STATE_DISABLED		0x19
#define XMLH_LTSSM_STATE_LPBK_ENTRY		0x1A
#define XMLH_LTSSM_STATE_LPBK_ACTIVE		0x1B
#define XMLH_LTSSM_STATE_LPBK_EXIT		0x1C
#define XMLH_LTSSM_STATE_LPBK_EXIT_TIMEOUT	0x1D
#define XMLH_LTSSM_STATE_HOT_RESET_ENTRY	0x1E
#define XMLH_LTSSM_STATE_HOT_RESET		0x1F
#define XMLH_LTSSM_STATE_MASK			0x3F
#define XMLH_LINK_UP				(1 << 6)

/* CR4 ID */
#define CFG_MSI_EN_ID				18

/* CR6 */
#define INTA_CTRL_INT				(1 << 7)
#define INTB_CTRL_INT				(1 << 8)
#define INTC_CTRL_INT				(1 << 9)
#define INTD_CTRL_INT				(1 << 10)
#define MSI_CTRL_INT				(1 << 26)

/* CR19 ID */
#define VEN_MSI_REQ_ID				11
#define VEN_MSI_FUN_NUM_ID			8
#define VEN_MSI_TC_ID				5
#define VEN_MSI_VECTOR_ID			0
#define VEN_MSI_REQ_EN		((u32)0x1 << VEN_MSI_REQ_ID)
#define VEN_MSI_FUN_NUM_MASK	((u32)0x7 << VEN_MSI_FUN_NUM_ID)
#define VEN_MSI_TC_MASK		((u32)0x7 << VEN_MSI_TC_ID)
#define VEN_MSI_VECTOR_MASK	((u32)0x1F << VEN_MSI_VECTOR_ID)

#define EXP_CAP_ID_OFFSET			0x70

#define to_spear13xx_pcie(x)	container_of(x, struct spear13xx_pcie, pp)

static int spear13xx_pcie_establish_link(struct pcie_port *pp)
{
	u32 val;
	struct spear13xx_pcie *spear13xx_pcie = to_spear13xx_pcie(pp);
	struct pcie_app_reg *app_reg = spear13xx_pcie->app_base;
	u32 exp_cap_off = EXP_CAP_ID_OFFSET;
	unsigned int retries;

	if (dw_pcie_link_up(pp)) {
		dev_err(pp->dev, "link already up\n");
		return 0;
	}

	dw_pcie_setup_rc(pp);

	/*
	 * this controller support only 128 bytes read size, however its
	 * default value in capability register is 512 bytes. So force
	 * it to 128 here.
	 */
	dw_pcie_cfg_read(pp->dbi_base + exp_cap_off + PCI_EXP_DEVCTL, 2, &val);
	val &= ~PCI_EXP_DEVCTL_READRQ;
	dw_pcie_cfg_write(pp->dbi_base + exp_cap_off + PCI_EXP_DEVCTL, 2, val);

	dw_pcie_cfg_write(pp->dbi_base + PCI_VENDOR_ID, 2, 0x104A);
	dw_pcie_cfg_write(pp->dbi_base + PCI_DEVICE_ID, 2, 0xCD80);

	/*
	 * if is_gen1 is set then handle it, so that some buggy card
	 * also works
	 */
	if (spear13xx_pcie->is_gen1) {
		dw_pcie_cfg_read(pp->dbi_base + exp_cap_off + PCI_EXP_LNKCAP,
					4, &val);
		if ((val & PCI_EXP_LNKCAP_SLS) != PCI_EXP_LNKCAP_SLS_2_5GB) {
			val &= ~((u32)PCI_EXP_LNKCAP_SLS);
			val |= PCI_EXP_LNKCAP_SLS_2_5GB;
			dw_pcie_cfg_write(pp->dbi_base + exp_cap_off +
				PCI_EXP_LNKCAP, 4, val);
		}

		dw_pcie_cfg_read(pp->dbi_base + exp_cap_off + PCI_EXP_LNKCTL2,
					2, &val);
		if ((val & PCI_EXP_LNKCAP_SLS) != PCI_EXP_LNKCAP_SLS_2_5GB) {
			val &= ~((u32)PCI_EXP_LNKCAP_SLS);
			val |= PCI_EXP_LNKCAP_SLS_2_5GB;
			dw_pcie_cfg_write(pp->dbi_base + exp_cap_off +
					PCI_EXP_LNKCTL2, 2, val);
		}
	}

	/* enable ltssm */
	writel(DEVICE_TYPE_RC | (1 << MISCTRL_EN_ID)
			| (1 << APP_LTSSM_ENABLE_ID)
			| ((u32)1 << REG_TRANSLATION_ENABLE),
			&app_reg->app_ctrl_0);

	/* check if the link is up or not */
	for (retries = 0; retries < 10; retries++) {
		if (dw_pcie_link_up(pp)) {
			dev_info(pp->dev, "link up\n");
			return 0;
		}
		mdelay(100);
	}

	dev_err(pp->dev, "link Fail\n");
	return -EINVAL;
}

static irqreturn_t spear13xx_pcie_irq_handler(int irq, void *arg)
{
	struct pcie_port *pp = arg;
	struct spear13xx_pcie *spear13xx_pcie = to_spear13xx_pcie(pp);
	struct pcie_app_reg *app_reg = spear13xx_pcie->app_base;
	unsigned int status;

	status = readl(&app_reg->int_sts);

	if (status & MSI_CTRL_INT) {
		BUG_ON(!IS_ENABLED(CONFIG_PCI_MSI));
		dw_handle_msi_irq(pp);
	}

	writel(status, &app_reg->int_clr);

	return IRQ_HANDLED;
}

static void spear13xx_pcie_enable_interrupts(struct pcie_port *pp)
{
	struct spear13xx_pcie *spear13xx_pcie = to_spear13xx_pcie(pp);
	struct pcie_app_reg *app_reg = spear13xx_pcie->app_base;

	/* Enable MSI interrupt */
	if (IS_ENABLED(CONFIG_PCI_MSI)) {
		dw_pcie_msi_init(pp);
		writel(readl(&app_reg->int_mask) |
				MSI_CTRL_INT, &app_reg->int_mask);
	}
}

static int spear13xx_pcie_link_up(struct pcie_port *pp)
{
	struct spear13xx_pcie *spear13xx_pcie = to_spear13xx_pcie(pp);
	struct pcie_app_reg *app_reg = spear13xx_pcie->app_base;

	if (readl(&app_reg->app_status_1) & XMLH_LINK_UP)
		return 1;

	return 0;
}

static void spear13xx_pcie_host_init(struct pcie_port *pp)
{
	spear13xx_pcie_establish_link(pp);
	spear13xx_pcie_enable_interrupts(pp);
}

static struct pcie_host_ops spear13xx_pcie_host_ops = {
	.link_up = spear13xx_pcie_link_up,
	.host_init = spear13xx_pcie_host_init,
};

static int spear13xx_add_pcie_port(struct pcie_port *pp,
					 struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	int ret;

	pp->irq = platform_get_irq(pdev, 0);
	if (!pp->irq) {
		dev_err(dev, "failed to get irq\n");
		return -ENODEV;
	}
	ret = devm_request_irq(dev, pp->irq, spear13xx_pcie_irq_handler,
			       IRQF_SHARED | IRQF_NO_THREAD,
			       "spear1340-pcie", pp);
	if (ret) {
		dev_err(dev, "failed to request irq %d\n", pp->irq);
		return ret;
	}

	pp->root_bus_nr = -1;
	pp->ops = &spear13xx_pcie_host_ops;

	ret = dw_pcie_host_init(pp);
	if (ret) {
		dev_err(dev, "failed to initialize host\n");
		return ret;
	}

	return 0;
}

static int spear13xx_pcie_probe(struct platform_device *pdev)
{
	struct spear13xx_pcie *spear13xx_pcie;
	struct pcie_port *pp;
	struct device *dev = &pdev->dev;
	struct device_node *np = pdev->dev.of_node;
	struct resource *dbi_base;
	int ret;

	spear13xx_pcie = devm_kzalloc(dev, sizeof(*spear13xx_pcie), GFP_KERNEL);
	if (!spear13xx_pcie)
		return -ENOMEM;

	spear13xx_pcie->phy = devm_phy_get(dev, "pcie-phy");
	if (IS_ERR(spear13xx_pcie->phy)) {
		ret = PTR_ERR(spear13xx_pcie->phy);
		if (ret == -EPROBE_DEFER)
			dev_info(dev, "probe deferred\n");
		else
			dev_err(dev, "couldn't get pcie-phy\n");
		return ret;
	}

	phy_init(spear13xx_pcie->phy);

	spear13xx_pcie->clk = devm_clk_get(dev, NULL);
	if (IS_ERR(spear13xx_pcie->clk)) {
		dev_err(dev, "couldn't get clk for pcie\n");
		return PTR_ERR(spear13xx_pcie->clk);
	}
	ret = clk_prepare_enable(spear13xx_pcie->clk);
	if (ret) {
		dev_err(dev, "couldn't enable clk for pcie\n");
		return ret;
	}

	pp = &spear13xx_pcie->pp;

	pp->dev = dev;

	dbi_base = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dbi");
	pp->dbi_base = devm_ioremap_resource(dev, dbi_base);
	if (IS_ERR(pp->dbi_base)) {
		dev_err(dev, "couldn't remap dbi base %p\n", dbi_base);
		ret = PTR_ERR(pp->dbi_base);
		goto fail_clk;
	}
	spear13xx_pcie->app_base = pp->dbi_base + 0x2000;

	if (of_property_read_bool(np, "st,pcie-is-gen1"))
		spear13xx_pcie->is_gen1 = true;

	ret = spear13xx_add_pcie_port(pp, pdev);
	if (ret < 0)
		goto fail_clk;

	platform_set_drvdata(pdev, spear13xx_pcie);
	return 0;

fail_clk:
	clk_disable_unprepare(spear13xx_pcie->clk);

	return ret;
}

static const struct of_device_id spear13xx_pcie_of_match[] = {
	{ .compatible = "st,spear1340-pcie", },
	{},
};
MODULE_DEVICE_TABLE(of, spear13xx_pcie_of_match);

static struct platform_driver spear13xx_pcie_driver = {
	.probe		= spear13xx_pcie_probe,
	.driver = {
		.name	= "spear-pcie",
		.of_match_table = of_match_ptr(spear13xx_pcie_of_match),
	},
};

/* SPEAr13xx PCIe driver does not allow module unload */

static int __init spear13xx_pcie_init(void)
{
	return platform_driver_register(&spear13xx_pcie_driver);
}
module_init(spear13xx_pcie_init);

MODULE_DESCRIPTION("ST Microelectronics SPEAr13xx PCIe host controller driver");
MODULE_AUTHOR("Pratyush Anand <pratyush.anand@gmail.com>");
MODULE_LICENSE("GPL v2");