1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * PCIe host controller driver for NWL PCIe Bridge
4  * Based on pcie-xilinx.c, pci-tegra.c
5  *
6  * (C) Copyright 2014 - 2015, Xilinx, Inc.
7  */
8 
9 #include <linux/clk.h>
10 #include <linux/delay.h>
11 #include <linux/interrupt.h>
12 #include <linux/irq.h>
13 #include <linux/irqdomain.h>
14 #include <linux/kernel.h>
15 #include <linux/init.h>
16 #include <linux/msi.h>
17 #include <linux/of_address.h>
18 #include <linux/of_pci.h>
19 #include <linux/of_platform.h>
20 #include <linux/pci.h>
21 #include <linux/pci-ecam.h>
22 #include <linux/platform_device.h>
23 #include <linux/irqchip/chained_irq.h>
24 
25 #include "../pci.h"
26 
27 /* Bridge core config registers */
28 #define BRCFG_PCIE_RX0			0x00000000
29 #define BRCFG_PCIE_RX1			0x00000004
30 #define BRCFG_INTERRUPT			0x00000010
31 #define BRCFG_PCIE_RX_MSG_FILTER	0x00000020
32 
33 /* Egress - Bridge translation registers */
34 #define E_BREG_CAPABILITIES		0x00000200
35 #define E_BREG_CONTROL			0x00000208
36 #define E_BREG_BASE_LO			0x00000210
37 #define E_BREG_BASE_HI			0x00000214
38 #define E_ECAM_CAPABILITIES		0x00000220
39 #define E_ECAM_CONTROL			0x00000228
40 #define E_ECAM_BASE_LO			0x00000230
41 #define E_ECAM_BASE_HI			0x00000234
42 
43 /* Ingress - address translations */
44 #define I_MSII_CAPABILITIES		0x00000300
45 #define I_MSII_CONTROL			0x00000308
46 #define I_MSII_BASE_LO			0x00000310
47 #define I_MSII_BASE_HI			0x00000314
48 
49 #define I_ISUB_CONTROL			0x000003E8
50 #define SET_ISUB_CONTROL		BIT(0)
51 /* Rxed msg fifo  - Interrupt status registers */
52 #define MSGF_MISC_STATUS		0x00000400
53 #define MSGF_MISC_MASK			0x00000404
54 #define MSGF_LEG_STATUS			0x00000420
55 #define MSGF_LEG_MASK			0x00000424
56 #define MSGF_MSI_STATUS_LO		0x00000440
57 #define MSGF_MSI_STATUS_HI		0x00000444
58 #define MSGF_MSI_MASK_LO		0x00000448
59 #define MSGF_MSI_MASK_HI		0x0000044C
60 
61 /* Msg filter mask bits */
62 #define CFG_ENABLE_PM_MSG_FWD		BIT(1)
63 #define CFG_ENABLE_INT_MSG_FWD		BIT(2)
64 #define CFG_ENABLE_ERR_MSG_FWD		BIT(3)
65 #define CFG_ENABLE_MSG_FILTER_MASK	(CFG_ENABLE_PM_MSG_FWD | \
66 					CFG_ENABLE_INT_MSG_FWD | \
67 					CFG_ENABLE_ERR_MSG_FWD)
68 
69 /* Misc interrupt status mask bits */
70 #define MSGF_MISC_SR_RXMSG_AVAIL	BIT(0)
71 #define MSGF_MISC_SR_RXMSG_OVER		BIT(1)
72 #define MSGF_MISC_SR_SLAVE_ERR		BIT(4)
73 #define MSGF_MISC_SR_MASTER_ERR		BIT(5)
74 #define MSGF_MISC_SR_I_ADDR_ERR		BIT(6)
75 #define MSGF_MISC_SR_E_ADDR_ERR		BIT(7)
76 #define MSGF_MISC_SR_FATAL_AER		BIT(16)
77 #define MSGF_MISC_SR_NON_FATAL_AER	BIT(17)
78 #define MSGF_MISC_SR_CORR_AER		BIT(18)
79 #define MSGF_MISC_SR_UR_DETECT		BIT(20)
80 #define MSGF_MISC_SR_NON_FATAL_DEV	BIT(22)
81 #define MSGF_MISC_SR_FATAL_DEV		BIT(23)
82 #define MSGF_MISC_SR_LINK_DOWN		BIT(24)
83 #define MSGF_MISC_SR_LINK_AUTO_BWIDTH	BIT(25)
84 #define MSGF_MISC_SR_LINK_BWIDTH	BIT(26)
85 
86 #define MSGF_MISC_SR_MASKALL		(MSGF_MISC_SR_RXMSG_AVAIL | \
87 					MSGF_MISC_SR_RXMSG_OVER | \
88 					MSGF_MISC_SR_SLAVE_ERR | \
89 					MSGF_MISC_SR_MASTER_ERR | \
90 					MSGF_MISC_SR_I_ADDR_ERR | \
91 					MSGF_MISC_SR_E_ADDR_ERR | \
92 					MSGF_MISC_SR_FATAL_AER | \
93 					MSGF_MISC_SR_NON_FATAL_AER | \
94 					MSGF_MISC_SR_CORR_AER | \
95 					MSGF_MISC_SR_UR_DETECT | \
96 					MSGF_MISC_SR_NON_FATAL_DEV | \
97 					MSGF_MISC_SR_FATAL_DEV | \
98 					MSGF_MISC_SR_LINK_DOWN | \
99 					MSGF_MISC_SR_LINK_AUTO_BWIDTH | \
100 					MSGF_MISC_SR_LINK_BWIDTH)
101 
102 /* Legacy interrupt status mask bits */
103 #define MSGF_LEG_SR_INTA		BIT(0)
104 #define MSGF_LEG_SR_INTB		BIT(1)
105 #define MSGF_LEG_SR_INTC		BIT(2)
106 #define MSGF_LEG_SR_INTD		BIT(3)
107 #define MSGF_LEG_SR_MASKALL		(MSGF_LEG_SR_INTA | MSGF_LEG_SR_INTB | \
108 					MSGF_LEG_SR_INTC | MSGF_LEG_SR_INTD)
109 
110 /* MSI interrupt status mask bits */
111 #define MSGF_MSI_SR_LO_MASK		GENMASK(31, 0)
112 #define MSGF_MSI_SR_HI_MASK		GENMASK(31, 0)
113 
114 #define MSII_PRESENT			BIT(0)
115 #define MSII_ENABLE			BIT(0)
116 #define MSII_STATUS_ENABLE		BIT(15)
117 
118 /* Bridge config interrupt mask */
119 #define BRCFG_INTERRUPT_MASK		BIT(0)
120 #define BREG_PRESENT			BIT(0)
121 #define BREG_ENABLE			BIT(0)
122 #define BREG_ENABLE_FORCE		BIT(1)
123 
124 /* E_ECAM status mask bits */
125 #define E_ECAM_PRESENT			BIT(0)
126 #define E_ECAM_CR_ENABLE		BIT(0)
127 #define E_ECAM_SIZE_LOC			GENMASK(20, 16)
128 #define E_ECAM_SIZE_SHIFT		16
129 #define NWL_ECAM_VALUE_DEFAULT		12
130 
131 #define CFG_DMA_REG_BAR			GENMASK(2, 0)
132 #define CFG_PCIE_CACHE			GENMASK(7, 0)
133 
134 #define INT_PCI_MSI_NR			(2 * 32)
135 
136 /* Readin the PS_LINKUP */
137 #define PS_LINKUP_OFFSET		0x00000238
138 #define PCIE_PHY_LINKUP_BIT		BIT(0)
139 #define PHY_RDY_LINKUP_BIT		BIT(1)
140 
141 /* Parameters for the waiting for link up routine */
142 #define LINK_WAIT_MAX_RETRIES          10
143 #define LINK_WAIT_USLEEP_MIN           90000
144 #define LINK_WAIT_USLEEP_MAX           100000
145 
146 struct nwl_msi {			/* MSI information */
147 	struct irq_domain *msi_domain;
148 	DECLARE_BITMAP(bitmap, INT_PCI_MSI_NR);
149 	struct irq_domain *dev_domain;
150 	struct mutex lock;		/* protect bitmap variable */
151 	int irq_msi0;
152 	int irq_msi1;
153 };
154 
155 struct nwl_pcie {
156 	struct device *dev;
157 	void __iomem *breg_base;
158 	void __iomem *pcireg_base;
159 	void __iomem *ecam_base;
160 	phys_addr_t phys_breg_base;	/* Physical Bridge Register Base */
161 	phys_addr_t phys_pcie_reg_base;	/* Physical PCIe Controller Base */
162 	phys_addr_t phys_ecam_base;	/* Physical Configuration Base */
163 	u32 breg_size;
164 	u32 pcie_reg_size;
165 	u32 ecam_size;
166 	int irq_intx;
167 	int irq_misc;
168 	u32 ecam_value;
169 	u8 last_busno;
170 	struct nwl_msi msi;
171 	struct irq_domain *legacy_irq_domain;
172 	struct clk *clk;
173 	raw_spinlock_t leg_mask_lock;
174 };
175 
nwl_bridge_readl(struct nwl_pcie * pcie,u32 off)176 static inline u32 nwl_bridge_readl(struct nwl_pcie *pcie, u32 off)
177 {
178 	return readl(pcie->breg_base + off);
179 }
180 
nwl_bridge_writel(struct nwl_pcie * pcie,u32 val,u32 off)181 static inline void nwl_bridge_writel(struct nwl_pcie *pcie, u32 val, u32 off)
182 {
183 	writel(val, pcie->breg_base + off);
184 }
185 
nwl_pcie_link_up(struct nwl_pcie * pcie)186 static bool nwl_pcie_link_up(struct nwl_pcie *pcie)
187 {
188 	if (readl(pcie->pcireg_base + PS_LINKUP_OFFSET) & PCIE_PHY_LINKUP_BIT)
189 		return true;
190 	return false;
191 }
192 
nwl_phy_link_up(struct nwl_pcie * pcie)193 static bool nwl_phy_link_up(struct nwl_pcie *pcie)
194 {
195 	if (readl(pcie->pcireg_base + PS_LINKUP_OFFSET) & PHY_RDY_LINKUP_BIT)
196 		return true;
197 	return false;
198 }
199 
nwl_wait_for_link(struct nwl_pcie * pcie)200 static int nwl_wait_for_link(struct nwl_pcie *pcie)
201 {
202 	struct device *dev = pcie->dev;
203 	int retries;
204 
205 	/* check if the link is up or not */
206 	for (retries = 0; retries < LINK_WAIT_MAX_RETRIES; retries++) {
207 		if (nwl_phy_link_up(pcie))
208 			return 0;
209 		usleep_range(LINK_WAIT_USLEEP_MIN, LINK_WAIT_USLEEP_MAX);
210 	}
211 
212 	dev_err(dev, "PHY link never came up\n");
213 	return -ETIMEDOUT;
214 }
215 
nwl_pcie_valid_device(struct pci_bus * bus,unsigned int devfn)216 static bool nwl_pcie_valid_device(struct pci_bus *bus, unsigned int devfn)
217 {
218 	struct nwl_pcie *pcie = bus->sysdata;
219 
220 	/* Check link before accessing downstream ports */
221 	if (!pci_is_root_bus(bus)) {
222 		if (!nwl_pcie_link_up(pcie))
223 			return false;
224 	} else if (devfn > 0)
225 		/* Only one device down on each root port */
226 		return false;
227 
228 	return true;
229 }
230 
231 /**
232  * nwl_pcie_map_bus - Get configuration base
233  *
234  * @bus: Bus structure of current bus
235  * @devfn: Device/function
236  * @where: Offset from base
237  *
238  * Return: Base address of the configuration space needed to be
239  *	   accessed.
240  */
nwl_pcie_map_bus(struct pci_bus * bus,unsigned int devfn,int where)241 static void __iomem *nwl_pcie_map_bus(struct pci_bus *bus, unsigned int devfn,
242 				      int where)
243 {
244 	struct nwl_pcie *pcie = bus->sysdata;
245 
246 	if (!nwl_pcie_valid_device(bus, devfn))
247 		return NULL;
248 
249 	return pcie->ecam_base + PCIE_ECAM_OFFSET(bus->number, devfn, where);
250 }
251 
252 /* PCIe operations */
253 static struct pci_ops nwl_pcie_ops = {
254 	.map_bus = nwl_pcie_map_bus,
255 	.read  = pci_generic_config_read,
256 	.write = pci_generic_config_write,
257 };
258 
nwl_pcie_misc_handler(int irq,void * data)259 static irqreturn_t nwl_pcie_misc_handler(int irq, void *data)
260 {
261 	struct nwl_pcie *pcie = data;
262 	struct device *dev = pcie->dev;
263 	u32 misc_stat;
264 
265 	/* Checking for misc interrupts */
266 	misc_stat = nwl_bridge_readl(pcie, MSGF_MISC_STATUS) &
267 				     MSGF_MISC_SR_MASKALL;
268 	if (!misc_stat)
269 		return IRQ_NONE;
270 
271 	if (misc_stat & MSGF_MISC_SR_RXMSG_OVER)
272 		dev_err(dev, "Received Message FIFO Overflow\n");
273 
274 	if (misc_stat & MSGF_MISC_SR_SLAVE_ERR)
275 		dev_err(dev, "Slave error\n");
276 
277 	if (misc_stat & MSGF_MISC_SR_MASTER_ERR)
278 		dev_err(dev, "Master error\n");
279 
280 	if (misc_stat & MSGF_MISC_SR_I_ADDR_ERR)
281 		dev_err(dev, "In Misc Ingress address translation error\n");
282 
283 	if (misc_stat & MSGF_MISC_SR_E_ADDR_ERR)
284 		dev_err(dev, "In Misc Egress address translation error\n");
285 
286 	if (misc_stat & MSGF_MISC_SR_FATAL_AER)
287 		dev_err(dev, "Fatal Error in AER Capability\n");
288 
289 	if (misc_stat & MSGF_MISC_SR_NON_FATAL_AER)
290 		dev_err(dev, "Non-Fatal Error in AER Capability\n");
291 
292 	if (misc_stat & MSGF_MISC_SR_CORR_AER)
293 		dev_err(dev, "Correctable Error in AER Capability\n");
294 
295 	if (misc_stat & MSGF_MISC_SR_UR_DETECT)
296 		dev_err(dev, "Unsupported request Detected\n");
297 
298 	if (misc_stat & MSGF_MISC_SR_NON_FATAL_DEV)
299 		dev_err(dev, "Non-Fatal Error Detected\n");
300 
301 	if (misc_stat & MSGF_MISC_SR_FATAL_DEV)
302 		dev_err(dev, "Fatal Error Detected\n");
303 
304 	if (misc_stat & MSGF_MISC_SR_LINK_AUTO_BWIDTH)
305 		dev_info(dev, "Link Autonomous Bandwidth Management Status bit set\n");
306 
307 	if (misc_stat & MSGF_MISC_SR_LINK_BWIDTH)
308 		dev_info(dev, "Link Bandwidth Management Status bit set\n");
309 
310 	/* Clear misc interrupt status */
311 	nwl_bridge_writel(pcie, misc_stat, MSGF_MISC_STATUS);
312 
313 	return IRQ_HANDLED;
314 }
315 
nwl_pcie_leg_handler(struct irq_desc * desc)316 static void nwl_pcie_leg_handler(struct irq_desc *desc)
317 {
318 	struct irq_chip *chip = irq_desc_get_chip(desc);
319 	struct nwl_pcie *pcie;
320 	unsigned long status;
321 	u32 bit;
322 
323 	chained_irq_enter(chip, desc);
324 	pcie = irq_desc_get_handler_data(desc);
325 
326 	while ((status = nwl_bridge_readl(pcie, MSGF_LEG_STATUS) &
327 				MSGF_LEG_SR_MASKALL) != 0) {
328 		for_each_set_bit(bit, &status, PCI_NUM_INTX)
329 			generic_handle_domain_irq(pcie->legacy_irq_domain, bit);
330 	}
331 
332 	chained_irq_exit(chip, desc);
333 }
334 
nwl_pcie_handle_msi_irq(struct nwl_pcie * pcie,u32 status_reg)335 static void nwl_pcie_handle_msi_irq(struct nwl_pcie *pcie, u32 status_reg)
336 {
337 	struct nwl_msi *msi = &pcie->msi;
338 	unsigned long status;
339 	u32 bit;
340 
341 	while ((status = nwl_bridge_readl(pcie, status_reg)) != 0) {
342 		for_each_set_bit(bit, &status, 32) {
343 			nwl_bridge_writel(pcie, 1 << bit, status_reg);
344 			generic_handle_domain_irq(msi->dev_domain, bit);
345 		}
346 	}
347 }
348 
nwl_pcie_msi_handler_high(struct irq_desc * desc)349 static void nwl_pcie_msi_handler_high(struct irq_desc *desc)
350 {
351 	struct irq_chip *chip = irq_desc_get_chip(desc);
352 	struct nwl_pcie *pcie = irq_desc_get_handler_data(desc);
353 
354 	chained_irq_enter(chip, desc);
355 	nwl_pcie_handle_msi_irq(pcie, MSGF_MSI_STATUS_HI);
356 	chained_irq_exit(chip, desc);
357 }
358 
nwl_pcie_msi_handler_low(struct irq_desc * desc)359 static void nwl_pcie_msi_handler_low(struct irq_desc *desc)
360 {
361 	struct irq_chip *chip = irq_desc_get_chip(desc);
362 	struct nwl_pcie *pcie = irq_desc_get_handler_data(desc);
363 
364 	chained_irq_enter(chip, desc);
365 	nwl_pcie_handle_msi_irq(pcie, MSGF_MSI_STATUS_LO);
366 	chained_irq_exit(chip, desc);
367 }
368 
nwl_mask_leg_irq(struct irq_data * data)369 static void nwl_mask_leg_irq(struct irq_data *data)
370 {
371 	struct nwl_pcie *pcie = irq_data_get_irq_chip_data(data);
372 	unsigned long flags;
373 	u32 mask;
374 	u32 val;
375 
376 	mask = 1 << data->hwirq;
377 	raw_spin_lock_irqsave(&pcie->leg_mask_lock, flags);
378 	val = nwl_bridge_readl(pcie, MSGF_LEG_MASK);
379 	nwl_bridge_writel(pcie, (val & (~mask)), MSGF_LEG_MASK);
380 	raw_spin_unlock_irqrestore(&pcie->leg_mask_lock, flags);
381 }
382 
nwl_unmask_leg_irq(struct irq_data * data)383 static void nwl_unmask_leg_irq(struct irq_data *data)
384 {
385 	struct nwl_pcie *pcie = irq_data_get_irq_chip_data(data);
386 	unsigned long flags;
387 	u32 mask;
388 	u32 val;
389 
390 	mask = 1 << data->hwirq;
391 	raw_spin_lock_irqsave(&pcie->leg_mask_lock, flags);
392 	val = nwl_bridge_readl(pcie, MSGF_LEG_MASK);
393 	nwl_bridge_writel(pcie, (val | mask), MSGF_LEG_MASK);
394 	raw_spin_unlock_irqrestore(&pcie->leg_mask_lock, flags);
395 }
396 
397 static struct irq_chip nwl_leg_irq_chip = {
398 	.name = "nwl_pcie:legacy",
399 	.irq_enable = nwl_unmask_leg_irq,
400 	.irq_disable = nwl_mask_leg_irq,
401 	.irq_mask = nwl_mask_leg_irq,
402 	.irq_unmask = nwl_unmask_leg_irq,
403 };
404 
nwl_legacy_map(struct irq_domain * domain,unsigned int irq,irq_hw_number_t hwirq)405 static int nwl_legacy_map(struct irq_domain *domain, unsigned int irq,
406 			  irq_hw_number_t hwirq)
407 {
408 	irq_set_chip_and_handler(irq, &nwl_leg_irq_chip, handle_level_irq);
409 	irq_set_chip_data(irq, domain->host_data);
410 	irq_set_status_flags(irq, IRQ_LEVEL);
411 
412 	return 0;
413 }
414 
415 static const struct irq_domain_ops legacy_domain_ops = {
416 	.map = nwl_legacy_map,
417 	.xlate = pci_irqd_intx_xlate,
418 };
419 
420 #ifdef CONFIG_PCI_MSI
421 static struct irq_chip nwl_msi_irq_chip = {
422 	.name = "nwl_pcie:msi",
423 	.irq_enable = pci_msi_unmask_irq,
424 	.irq_disable = pci_msi_mask_irq,
425 	.irq_mask = pci_msi_mask_irq,
426 	.irq_unmask = pci_msi_unmask_irq,
427 };
428 
429 static struct msi_domain_info nwl_msi_domain_info = {
430 	.flags = (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
431 		  MSI_FLAG_MULTI_PCI_MSI),
432 	.chip = &nwl_msi_irq_chip,
433 };
434 #endif
435 
nwl_compose_msi_msg(struct irq_data * data,struct msi_msg * msg)436 static void nwl_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
437 {
438 	struct nwl_pcie *pcie = irq_data_get_irq_chip_data(data);
439 	phys_addr_t msi_addr = pcie->phys_pcie_reg_base;
440 
441 	msg->address_lo = lower_32_bits(msi_addr);
442 	msg->address_hi = upper_32_bits(msi_addr);
443 	msg->data = data->hwirq;
444 }
445 
nwl_msi_set_affinity(struct irq_data * irq_data,const struct cpumask * mask,bool force)446 static int nwl_msi_set_affinity(struct irq_data *irq_data,
447 				const struct cpumask *mask, bool force)
448 {
449 	return -EINVAL;
450 }
451 
452 static struct irq_chip nwl_irq_chip = {
453 	.name = "Xilinx MSI",
454 	.irq_compose_msi_msg = nwl_compose_msi_msg,
455 	.irq_set_affinity = nwl_msi_set_affinity,
456 };
457 
nwl_irq_domain_alloc(struct irq_domain * domain,unsigned int virq,unsigned int nr_irqs,void * args)458 static int nwl_irq_domain_alloc(struct irq_domain *domain, unsigned int virq,
459 				unsigned int nr_irqs, void *args)
460 {
461 	struct nwl_pcie *pcie = domain->host_data;
462 	struct nwl_msi *msi = &pcie->msi;
463 	int bit;
464 	int i;
465 
466 	mutex_lock(&msi->lock);
467 	bit = bitmap_find_free_region(msi->bitmap, INT_PCI_MSI_NR,
468 				      get_count_order(nr_irqs));
469 	if (bit < 0) {
470 		mutex_unlock(&msi->lock);
471 		return -ENOSPC;
472 	}
473 
474 	for (i = 0; i < nr_irqs; i++) {
475 		irq_domain_set_info(domain, virq + i, bit + i, &nwl_irq_chip,
476 				    domain->host_data, handle_simple_irq,
477 				    NULL, NULL);
478 	}
479 	mutex_unlock(&msi->lock);
480 	return 0;
481 }
482 
nwl_irq_domain_free(struct irq_domain * domain,unsigned int virq,unsigned int nr_irqs)483 static void nwl_irq_domain_free(struct irq_domain *domain, unsigned int virq,
484 				unsigned int nr_irqs)
485 {
486 	struct irq_data *data = irq_domain_get_irq_data(domain, virq);
487 	struct nwl_pcie *pcie = irq_data_get_irq_chip_data(data);
488 	struct nwl_msi *msi = &pcie->msi;
489 
490 	mutex_lock(&msi->lock);
491 	bitmap_release_region(msi->bitmap, data->hwirq,
492 			      get_count_order(nr_irqs));
493 	mutex_unlock(&msi->lock);
494 }
495 
496 static const struct irq_domain_ops dev_msi_domain_ops = {
497 	.alloc  = nwl_irq_domain_alloc,
498 	.free   = nwl_irq_domain_free,
499 };
500 
nwl_pcie_init_msi_irq_domain(struct nwl_pcie * pcie)501 static int nwl_pcie_init_msi_irq_domain(struct nwl_pcie *pcie)
502 {
503 #ifdef CONFIG_PCI_MSI
504 	struct device *dev = pcie->dev;
505 	struct fwnode_handle *fwnode = of_node_to_fwnode(dev->of_node);
506 	struct nwl_msi *msi = &pcie->msi;
507 
508 	msi->dev_domain = irq_domain_add_linear(NULL, INT_PCI_MSI_NR,
509 						&dev_msi_domain_ops, pcie);
510 	if (!msi->dev_domain) {
511 		dev_err(dev, "failed to create dev IRQ domain\n");
512 		return -ENOMEM;
513 	}
514 	msi->msi_domain = pci_msi_create_irq_domain(fwnode,
515 						    &nwl_msi_domain_info,
516 						    msi->dev_domain);
517 	if (!msi->msi_domain) {
518 		dev_err(dev, "failed to create msi IRQ domain\n");
519 		irq_domain_remove(msi->dev_domain);
520 		return -ENOMEM;
521 	}
522 #endif
523 	return 0;
524 }
525 
nwl_pcie_init_irq_domain(struct nwl_pcie * pcie)526 static int nwl_pcie_init_irq_domain(struct nwl_pcie *pcie)
527 {
528 	struct device *dev = pcie->dev;
529 	struct device_node *node = dev->of_node;
530 	struct device_node *legacy_intc_node;
531 
532 	legacy_intc_node = of_get_next_child(node, NULL);
533 	if (!legacy_intc_node) {
534 		dev_err(dev, "No legacy intc node found\n");
535 		return -EINVAL;
536 	}
537 
538 	pcie->legacy_irq_domain = irq_domain_add_linear(legacy_intc_node,
539 							PCI_NUM_INTX,
540 							&legacy_domain_ops,
541 							pcie);
542 	of_node_put(legacy_intc_node);
543 	if (!pcie->legacy_irq_domain) {
544 		dev_err(dev, "failed to create IRQ domain\n");
545 		return -ENOMEM;
546 	}
547 
548 	raw_spin_lock_init(&pcie->leg_mask_lock);
549 	nwl_pcie_init_msi_irq_domain(pcie);
550 	return 0;
551 }
552 
nwl_pcie_enable_msi(struct nwl_pcie * pcie)553 static int nwl_pcie_enable_msi(struct nwl_pcie *pcie)
554 {
555 	struct device *dev = pcie->dev;
556 	struct platform_device *pdev = to_platform_device(dev);
557 	struct nwl_msi *msi = &pcie->msi;
558 	unsigned long base;
559 	int ret;
560 
561 	mutex_init(&msi->lock);
562 
563 	/* Get msi_1 IRQ number */
564 	msi->irq_msi1 = platform_get_irq_byname(pdev, "msi1");
565 	if (msi->irq_msi1 < 0)
566 		return -EINVAL;
567 
568 	irq_set_chained_handler_and_data(msi->irq_msi1,
569 					 nwl_pcie_msi_handler_high, pcie);
570 
571 	/* Get msi_0 IRQ number */
572 	msi->irq_msi0 = platform_get_irq_byname(pdev, "msi0");
573 	if (msi->irq_msi0 < 0)
574 		return -EINVAL;
575 
576 	irq_set_chained_handler_and_data(msi->irq_msi0,
577 					 nwl_pcie_msi_handler_low, pcie);
578 
579 	/* Check for msii_present bit */
580 	ret = nwl_bridge_readl(pcie, I_MSII_CAPABILITIES) & MSII_PRESENT;
581 	if (!ret) {
582 		dev_err(dev, "MSI not present\n");
583 		return -EIO;
584 	}
585 
586 	/* Enable MSII */
587 	nwl_bridge_writel(pcie, nwl_bridge_readl(pcie, I_MSII_CONTROL) |
588 			  MSII_ENABLE, I_MSII_CONTROL);
589 
590 	/* Enable MSII status */
591 	nwl_bridge_writel(pcie, nwl_bridge_readl(pcie, I_MSII_CONTROL) |
592 			  MSII_STATUS_ENABLE, I_MSII_CONTROL);
593 
594 	/* setup AFI/FPCI range */
595 	base = pcie->phys_pcie_reg_base;
596 	nwl_bridge_writel(pcie, lower_32_bits(base), I_MSII_BASE_LO);
597 	nwl_bridge_writel(pcie, upper_32_bits(base), I_MSII_BASE_HI);
598 
599 	/*
600 	 * For high range MSI interrupts: disable, clear any pending,
601 	 * and enable
602 	 */
603 	nwl_bridge_writel(pcie, 0, MSGF_MSI_MASK_HI);
604 
605 	nwl_bridge_writel(pcie, nwl_bridge_readl(pcie,  MSGF_MSI_STATUS_HI) &
606 			  MSGF_MSI_SR_HI_MASK, MSGF_MSI_STATUS_HI);
607 
608 	nwl_bridge_writel(pcie, MSGF_MSI_SR_HI_MASK, MSGF_MSI_MASK_HI);
609 
610 	/*
611 	 * For low range MSI interrupts: disable, clear any pending,
612 	 * and enable
613 	 */
614 	nwl_bridge_writel(pcie, 0, MSGF_MSI_MASK_LO);
615 
616 	nwl_bridge_writel(pcie, nwl_bridge_readl(pcie, MSGF_MSI_STATUS_LO) &
617 			  MSGF_MSI_SR_LO_MASK, MSGF_MSI_STATUS_LO);
618 
619 	nwl_bridge_writel(pcie, MSGF_MSI_SR_LO_MASK, MSGF_MSI_MASK_LO);
620 
621 	return 0;
622 }
623 
nwl_pcie_bridge_init(struct nwl_pcie * pcie)624 static int nwl_pcie_bridge_init(struct nwl_pcie *pcie)
625 {
626 	struct device *dev = pcie->dev;
627 	struct platform_device *pdev = to_platform_device(dev);
628 	u32 breg_val, ecam_val, first_busno = 0;
629 	int err;
630 
631 	breg_val = nwl_bridge_readl(pcie, E_BREG_CAPABILITIES) & BREG_PRESENT;
632 	if (!breg_val) {
633 		dev_err(dev, "BREG is not present\n");
634 		return breg_val;
635 	}
636 
637 	/* Write bridge_off to breg base */
638 	nwl_bridge_writel(pcie, lower_32_bits(pcie->phys_breg_base),
639 			  E_BREG_BASE_LO);
640 	nwl_bridge_writel(pcie, upper_32_bits(pcie->phys_breg_base),
641 			  E_BREG_BASE_HI);
642 
643 	/* Enable BREG */
644 	nwl_bridge_writel(pcie, ~BREG_ENABLE_FORCE & BREG_ENABLE,
645 			  E_BREG_CONTROL);
646 
647 	/* Disable DMA channel registers */
648 	nwl_bridge_writel(pcie, nwl_bridge_readl(pcie, BRCFG_PCIE_RX0) |
649 			  CFG_DMA_REG_BAR, BRCFG_PCIE_RX0);
650 
651 	/* Enable Ingress subtractive decode translation */
652 	nwl_bridge_writel(pcie, SET_ISUB_CONTROL, I_ISUB_CONTROL);
653 
654 	/* Enable msg filtering details */
655 	nwl_bridge_writel(pcie, CFG_ENABLE_MSG_FILTER_MASK,
656 			  BRCFG_PCIE_RX_MSG_FILTER);
657 
658 	/* This routes the PCIe DMA traffic to go through CCI path */
659 	if (of_dma_is_coherent(dev->of_node))
660 		nwl_bridge_writel(pcie, nwl_bridge_readl(pcie, BRCFG_PCIE_RX1) |
661 				  CFG_PCIE_CACHE, BRCFG_PCIE_RX1);
662 
663 	err = nwl_wait_for_link(pcie);
664 	if (err)
665 		return err;
666 
667 	ecam_val = nwl_bridge_readl(pcie, E_ECAM_CAPABILITIES) & E_ECAM_PRESENT;
668 	if (!ecam_val) {
669 		dev_err(dev, "ECAM is not present\n");
670 		return ecam_val;
671 	}
672 
673 	/* Enable ECAM */
674 	nwl_bridge_writel(pcie, nwl_bridge_readl(pcie, E_ECAM_CONTROL) |
675 			  E_ECAM_CR_ENABLE, E_ECAM_CONTROL);
676 
677 	nwl_bridge_writel(pcie, nwl_bridge_readl(pcie, E_ECAM_CONTROL) |
678 			  (pcie->ecam_value << E_ECAM_SIZE_SHIFT),
679 			  E_ECAM_CONTROL);
680 
681 	nwl_bridge_writel(pcie, lower_32_bits(pcie->phys_ecam_base),
682 			  E_ECAM_BASE_LO);
683 	nwl_bridge_writel(pcie, upper_32_bits(pcie->phys_ecam_base),
684 			  E_ECAM_BASE_HI);
685 
686 	/* Get bus range */
687 	ecam_val = nwl_bridge_readl(pcie, E_ECAM_CONTROL);
688 	pcie->last_busno = (ecam_val & E_ECAM_SIZE_LOC) >> E_ECAM_SIZE_SHIFT;
689 	/* Write primary, secondary and subordinate bus numbers */
690 	ecam_val = first_busno;
691 	ecam_val |= (first_busno + 1) << 8;
692 	ecam_val |= (pcie->last_busno << E_ECAM_SIZE_SHIFT);
693 	writel(ecam_val, (pcie->ecam_base + PCI_PRIMARY_BUS));
694 
695 	if (nwl_pcie_link_up(pcie))
696 		dev_info(dev, "Link is UP\n");
697 	else
698 		dev_info(dev, "Link is DOWN\n");
699 
700 	/* Get misc IRQ number */
701 	pcie->irq_misc = platform_get_irq_byname(pdev, "misc");
702 	if (pcie->irq_misc < 0)
703 		return -EINVAL;
704 
705 	err = devm_request_irq(dev, pcie->irq_misc,
706 			       nwl_pcie_misc_handler, IRQF_SHARED,
707 			       "nwl_pcie:misc", pcie);
708 	if (err) {
709 		dev_err(dev, "fail to register misc IRQ#%d\n",
710 			pcie->irq_misc);
711 		return err;
712 	}
713 
714 	/* Disable all misc interrupts */
715 	nwl_bridge_writel(pcie, (u32)~MSGF_MISC_SR_MASKALL, MSGF_MISC_MASK);
716 
717 	/* Clear pending misc interrupts */
718 	nwl_bridge_writel(pcie, nwl_bridge_readl(pcie, MSGF_MISC_STATUS) &
719 			  MSGF_MISC_SR_MASKALL, MSGF_MISC_STATUS);
720 
721 	/* Enable all misc interrupts */
722 	nwl_bridge_writel(pcie, MSGF_MISC_SR_MASKALL, MSGF_MISC_MASK);
723 
724 	/* Disable all legacy interrupts */
725 	nwl_bridge_writel(pcie, (u32)~MSGF_LEG_SR_MASKALL, MSGF_LEG_MASK);
726 
727 	/* Clear pending legacy interrupts */
728 	nwl_bridge_writel(pcie, nwl_bridge_readl(pcie, MSGF_LEG_STATUS) &
729 			  MSGF_LEG_SR_MASKALL, MSGF_LEG_STATUS);
730 
731 	/* Enable all legacy interrupts */
732 	nwl_bridge_writel(pcie, MSGF_LEG_SR_MASKALL, MSGF_LEG_MASK);
733 
734 	/* Enable the bridge config interrupt */
735 	nwl_bridge_writel(pcie, nwl_bridge_readl(pcie, BRCFG_INTERRUPT) |
736 			  BRCFG_INTERRUPT_MASK, BRCFG_INTERRUPT);
737 
738 	return 0;
739 }
740 
nwl_pcie_parse_dt(struct nwl_pcie * pcie,struct platform_device * pdev)741 static int nwl_pcie_parse_dt(struct nwl_pcie *pcie,
742 			     struct platform_device *pdev)
743 {
744 	struct device *dev = pcie->dev;
745 	struct resource *res;
746 
747 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "breg");
748 	pcie->breg_base = devm_ioremap_resource(dev, res);
749 	if (IS_ERR(pcie->breg_base))
750 		return PTR_ERR(pcie->breg_base);
751 	pcie->phys_breg_base = res->start;
752 
753 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "pcireg");
754 	pcie->pcireg_base = devm_ioremap_resource(dev, res);
755 	if (IS_ERR(pcie->pcireg_base))
756 		return PTR_ERR(pcie->pcireg_base);
757 	pcie->phys_pcie_reg_base = res->start;
758 
759 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "cfg");
760 	pcie->ecam_base = devm_pci_remap_cfg_resource(dev, res);
761 	if (IS_ERR(pcie->ecam_base))
762 		return PTR_ERR(pcie->ecam_base);
763 	pcie->phys_ecam_base = res->start;
764 
765 	/* Get intx IRQ number */
766 	pcie->irq_intx = platform_get_irq_byname(pdev, "intx");
767 	if (pcie->irq_intx < 0)
768 		return pcie->irq_intx;
769 
770 	irq_set_chained_handler_and_data(pcie->irq_intx,
771 					 nwl_pcie_leg_handler, pcie);
772 
773 	return 0;
774 }
775 
776 static const struct of_device_id nwl_pcie_of_match[] = {
777 	{ .compatible = "xlnx,nwl-pcie-2.11", },
778 	{}
779 };
780 
nwl_pcie_probe(struct platform_device * pdev)781 static int nwl_pcie_probe(struct platform_device *pdev)
782 {
783 	struct device *dev = &pdev->dev;
784 	struct nwl_pcie *pcie;
785 	struct pci_host_bridge *bridge;
786 	int err;
787 
788 	bridge = devm_pci_alloc_host_bridge(dev, sizeof(*pcie));
789 	if (!bridge)
790 		return -ENODEV;
791 
792 	pcie = pci_host_bridge_priv(bridge);
793 	platform_set_drvdata(pdev, pcie);
794 
795 	pcie->dev = dev;
796 	pcie->ecam_value = NWL_ECAM_VALUE_DEFAULT;
797 
798 	err = nwl_pcie_parse_dt(pcie, pdev);
799 	if (err) {
800 		dev_err(dev, "Parsing DT failed\n");
801 		return err;
802 	}
803 
804 	pcie->clk = devm_clk_get(dev, NULL);
805 	if (IS_ERR(pcie->clk))
806 		return PTR_ERR(pcie->clk);
807 
808 	err = clk_prepare_enable(pcie->clk);
809 	if (err) {
810 		dev_err(dev, "can't enable PCIe ref clock\n");
811 		return err;
812 	}
813 
814 	err = nwl_pcie_bridge_init(pcie);
815 	if (err) {
816 		dev_err(dev, "HW Initialization failed\n");
817 		goto err_clk;
818 	}
819 
820 	err = nwl_pcie_init_irq_domain(pcie);
821 	if (err) {
822 		dev_err(dev, "Failed creating IRQ Domain\n");
823 		goto err_clk;
824 	}
825 
826 	bridge->sysdata = pcie;
827 	bridge->ops = &nwl_pcie_ops;
828 
829 	if (IS_ENABLED(CONFIG_PCI_MSI)) {
830 		err = nwl_pcie_enable_msi(pcie);
831 		if (err < 0) {
832 			dev_err(dev, "failed to enable MSI support: %d\n", err);
833 			goto err_clk;
834 		}
835 	}
836 
837 	err = pci_host_probe(bridge);
838 	if (!err)
839 		return 0;
840 
841 err_clk:
842 	clk_disable_unprepare(pcie->clk);
843 	return err;
844 }
845 
nwl_pcie_remove(struct platform_device * pdev)846 static void nwl_pcie_remove(struct platform_device *pdev)
847 {
848 	struct nwl_pcie *pcie = platform_get_drvdata(pdev);
849 
850 	clk_disable_unprepare(pcie->clk);
851 }
852 
853 static struct platform_driver nwl_pcie_driver = {
854 	.driver = {
855 		.name = "nwl-pcie",
856 		.suppress_bind_attrs = true,
857 		.of_match_table = nwl_pcie_of_match,
858 	},
859 	.probe = nwl_pcie_probe,
860 	.remove_new = nwl_pcie_remove,
861 };
862 builtin_platform_driver(nwl_pcie_driver);
863