1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Driver for the Aardvark PCIe controller, used on Marvell Armada
4  * 3700.
5  *
6  * Copyright (C) 2016 Marvell
7  *
8  * Author: Hezi Shahmoon <hezi.shahmoon@marvell.com>
9  */
10 
11 #include <linux/delay.h>
12 #include <linux/gpio/consumer.h>
13 #include <linux/interrupt.h>
14 #include <linux/irq.h>
15 #include <linux/irqdomain.h>
16 #include <linux/kernel.h>
17 #include <linux/module.h>
18 #include <linux/pci.h>
19 #include <linux/pci-ecam.h>
20 #include <linux/init.h>
21 #include <linux/phy/phy.h>
22 #include <linux/platform_device.h>
23 #include <linux/msi.h>
24 #include <linux/of_address.h>
25 #include <linux/of_gpio.h>
26 #include <linux/of_pci.h>
27 
28 #include "../pci.h"
29 #include "../pci-bridge-emul.h"
30 
31 /* PCIe core registers */
32 #define PCIE_CORE_DEV_ID_REG					0x0
33 #define PCIE_CORE_CMD_STATUS_REG				0x4
34 #define     PCIE_CORE_CMD_IO_ACCESS_EN				BIT(0)
35 #define     PCIE_CORE_CMD_MEM_ACCESS_EN				BIT(1)
36 #define     PCIE_CORE_CMD_MEM_IO_REQ_EN				BIT(2)
37 #define PCIE_CORE_DEV_REV_REG					0x8
38 #define PCIE_CORE_PCIEXP_CAP					0xc0
39 #define PCIE_CORE_ERR_CAPCTL_REG				0x118
40 #define     PCIE_CORE_ERR_CAPCTL_ECRC_CHK_TX			BIT(5)
41 #define     PCIE_CORE_ERR_CAPCTL_ECRC_CHK_TX_EN			BIT(6)
42 #define     PCIE_CORE_ERR_CAPCTL_ECRC_CHCK			BIT(7)
43 #define     PCIE_CORE_ERR_CAPCTL_ECRC_CHCK_RCV			BIT(8)
44 #define     PCIE_CORE_INT_A_ASSERT_ENABLE			1
45 #define     PCIE_CORE_INT_B_ASSERT_ENABLE			2
46 #define     PCIE_CORE_INT_C_ASSERT_ENABLE			3
47 #define     PCIE_CORE_INT_D_ASSERT_ENABLE			4
48 /* PIO registers base address and register offsets */
49 #define PIO_BASE_ADDR				0x4000
50 #define PIO_CTRL				(PIO_BASE_ADDR + 0x0)
51 #define   PIO_CTRL_TYPE_MASK			GENMASK(3, 0)
52 #define   PIO_CTRL_ADDR_WIN_DISABLE		BIT(24)
53 #define PIO_STAT				(PIO_BASE_ADDR + 0x4)
54 #define   PIO_COMPLETION_STATUS_SHIFT		7
55 #define   PIO_COMPLETION_STATUS_MASK		GENMASK(9, 7)
56 #define   PIO_COMPLETION_STATUS_OK		0
57 #define   PIO_COMPLETION_STATUS_UR		1
58 #define   PIO_COMPLETION_STATUS_CRS		2
59 #define   PIO_COMPLETION_STATUS_CA		4
60 #define   PIO_NON_POSTED_REQ			BIT(10)
61 #define PIO_ADDR_LS				(PIO_BASE_ADDR + 0x8)
62 #define PIO_ADDR_MS				(PIO_BASE_ADDR + 0xc)
63 #define PIO_WR_DATA				(PIO_BASE_ADDR + 0x10)
64 #define PIO_WR_DATA_STRB			(PIO_BASE_ADDR + 0x14)
65 #define PIO_RD_DATA				(PIO_BASE_ADDR + 0x18)
66 #define PIO_START				(PIO_BASE_ADDR + 0x1c)
67 #define PIO_ISR					(PIO_BASE_ADDR + 0x20)
68 #define PIO_ISRM				(PIO_BASE_ADDR + 0x24)
69 
70 /* Aardvark Control registers */
71 #define CONTROL_BASE_ADDR			0x4800
72 #define PCIE_CORE_CTRL0_REG			(CONTROL_BASE_ADDR + 0x0)
73 #define     PCIE_GEN_SEL_MSK			0x3
74 #define     PCIE_GEN_SEL_SHIFT			0x0
75 #define     SPEED_GEN_1				0
76 #define     SPEED_GEN_2				1
77 #define     SPEED_GEN_3				2
78 #define     IS_RC_MSK				1
79 #define     IS_RC_SHIFT				2
80 #define     LANE_CNT_MSK			0x18
81 #define     LANE_CNT_SHIFT			0x3
82 #define     LANE_COUNT_1			(0 << LANE_CNT_SHIFT)
83 #define     LANE_COUNT_2			(1 << LANE_CNT_SHIFT)
84 #define     LANE_COUNT_4			(2 << LANE_CNT_SHIFT)
85 #define     LANE_COUNT_8			(3 << LANE_CNT_SHIFT)
86 #define     LINK_TRAINING_EN			BIT(6)
87 #define     LEGACY_INTA				BIT(28)
88 #define     LEGACY_INTB				BIT(29)
89 #define     LEGACY_INTC				BIT(30)
90 #define     LEGACY_INTD				BIT(31)
91 #define PCIE_CORE_CTRL1_REG			(CONTROL_BASE_ADDR + 0x4)
92 #define     HOT_RESET_GEN			BIT(0)
93 #define PCIE_CORE_CTRL2_REG			(CONTROL_BASE_ADDR + 0x8)
94 #define     PCIE_CORE_CTRL2_RESERVED		0x7
95 #define     PCIE_CORE_CTRL2_TD_ENABLE		BIT(4)
96 #define     PCIE_CORE_CTRL2_STRICT_ORDER_ENABLE	BIT(5)
97 #define     PCIE_CORE_CTRL2_OB_WIN_ENABLE	BIT(6)
98 #define     PCIE_CORE_CTRL2_MSI_ENABLE		BIT(10)
99 #define PCIE_CORE_REF_CLK_REG			(CONTROL_BASE_ADDR + 0x14)
100 #define     PCIE_CORE_REF_CLK_TX_ENABLE		BIT(1)
101 #define PCIE_MSG_LOG_REG			(CONTROL_BASE_ADDR + 0x30)
102 #define PCIE_ISR0_REG				(CONTROL_BASE_ADDR + 0x40)
103 #define PCIE_MSG_PM_PME_MASK			BIT(7)
104 #define PCIE_ISR0_MASK_REG			(CONTROL_BASE_ADDR + 0x44)
105 #define     PCIE_ISR0_MSI_INT_PENDING		BIT(24)
106 #define     PCIE_ISR0_INTX_ASSERT(val)		BIT(16 + (val))
107 #define     PCIE_ISR0_INTX_DEASSERT(val)	BIT(20 + (val))
108 #define	    PCIE_ISR0_ALL_MASK			GENMASK(26, 0)
109 #define PCIE_ISR1_REG				(CONTROL_BASE_ADDR + 0x48)
110 #define PCIE_ISR1_MASK_REG			(CONTROL_BASE_ADDR + 0x4C)
111 #define     PCIE_ISR1_POWER_STATE_CHANGE	BIT(4)
112 #define     PCIE_ISR1_FLUSH			BIT(5)
113 #define     PCIE_ISR1_INTX_ASSERT(val)		BIT(8 + (val))
114 #define     PCIE_ISR1_ALL_MASK			GENMASK(11, 4)
115 #define PCIE_MSI_ADDR_LOW_REG			(CONTROL_BASE_ADDR + 0x50)
116 #define PCIE_MSI_ADDR_HIGH_REG			(CONTROL_BASE_ADDR + 0x54)
117 #define PCIE_MSI_STATUS_REG			(CONTROL_BASE_ADDR + 0x58)
118 #define PCIE_MSI_MASK_REG			(CONTROL_BASE_ADDR + 0x5C)
119 #define PCIE_MSI_PAYLOAD_REG			(CONTROL_BASE_ADDR + 0x9C)
120 
121 /* LMI registers base address and register offsets */
122 #define LMI_BASE_ADDR				0x6000
123 #define CFG_REG					(LMI_BASE_ADDR + 0x0)
124 #define     LTSSM_SHIFT				24
125 #define     LTSSM_MASK				0x3f
126 #define     LTSSM_L0				0x10
127 #define     RC_BAR_CONFIG			0x300
128 #define VENDOR_ID_REG				(LMI_BASE_ADDR + 0x44)
129 
130 /* PCIe core controller registers */
131 #define CTRL_CORE_BASE_ADDR			0x18000
132 #define CTRL_CONFIG_REG				(CTRL_CORE_BASE_ADDR + 0x0)
133 #define     CTRL_MODE_SHIFT			0x0
134 #define     CTRL_MODE_MASK			0x1
135 #define     PCIE_CORE_MODE_DIRECT		0x0
136 #define     PCIE_CORE_MODE_COMMAND		0x1
137 
138 /* PCIe Central Interrupts Registers */
139 #define CENTRAL_INT_BASE_ADDR			0x1b000
140 #define HOST_CTRL_INT_STATUS_REG		(CENTRAL_INT_BASE_ADDR + 0x0)
141 #define HOST_CTRL_INT_MASK_REG			(CENTRAL_INT_BASE_ADDR + 0x4)
142 #define     PCIE_IRQ_CMDQ_INT			BIT(0)
143 #define     PCIE_IRQ_MSI_STATUS_INT		BIT(1)
144 #define     PCIE_IRQ_CMD_SENT_DONE		BIT(3)
145 #define     PCIE_IRQ_DMA_INT			BIT(4)
146 #define     PCIE_IRQ_IB_DXFERDONE		BIT(5)
147 #define     PCIE_IRQ_OB_DXFERDONE		BIT(6)
148 #define     PCIE_IRQ_OB_RXFERDONE		BIT(7)
149 #define     PCIE_IRQ_COMPQ_INT			BIT(12)
150 #define     PCIE_IRQ_DIR_RD_DDR_DET		BIT(13)
151 #define     PCIE_IRQ_DIR_WR_DDR_DET		BIT(14)
152 #define     PCIE_IRQ_CORE_INT			BIT(16)
153 #define     PCIE_IRQ_CORE_INT_PIO		BIT(17)
154 #define     PCIE_IRQ_DPMU_INT			BIT(18)
155 #define     PCIE_IRQ_PCIE_MIS_INT		BIT(19)
156 #define     PCIE_IRQ_MSI_INT1_DET		BIT(20)
157 #define     PCIE_IRQ_MSI_INT2_DET		BIT(21)
158 #define     PCIE_IRQ_RC_DBELL_DET		BIT(22)
159 #define     PCIE_IRQ_EP_STATUS			BIT(23)
160 #define     PCIE_IRQ_ALL_MASK			0xfff0fb
161 #define     PCIE_IRQ_ENABLE_INTS_MASK		PCIE_IRQ_CORE_INT
162 
163 /* Transaction types */
164 #define PCIE_CONFIG_RD_TYPE0			0x8
165 #define PCIE_CONFIG_RD_TYPE1			0x9
166 #define PCIE_CONFIG_WR_TYPE0			0xa
167 #define PCIE_CONFIG_WR_TYPE1			0xb
168 
169 #define PIO_RETRY_CNT			500
170 #define PIO_RETRY_DELAY			2 /* 2 us*/
171 
172 #define LINK_WAIT_MAX_RETRIES		10
173 #define LINK_WAIT_USLEEP_MIN		90000
174 #define LINK_WAIT_USLEEP_MAX		100000
175 #define RETRAIN_WAIT_MAX_RETRIES	10
176 #define RETRAIN_WAIT_USLEEP_US		2000
177 
178 #define MSI_IRQ_NUM			32
179 
180 struct advk_pcie {
181 	struct platform_device *pdev;
182 	void __iomem *base;
183 	struct irq_domain *irq_domain;
184 	struct irq_chip irq_chip;
185 	struct irq_domain *msi_domain;
186 	struct irq_domain *msi_inner_domain;
187 	struct irq_chip msi_bottom_irq_chip;
188 	struct irq_chip msi_irq_chip;
189 	struct msi_domain_info msi_domain_info;
190 	DECLARE_BITMAP(msi_used, MSI_IRQ_NUM);
191 	struct mutex msi_used_lock;
192 	u16 msi_msg;
193 	int link_gen;
194 	struct pci_bridge_emul bridge;
195 	struct gpio_desc *reset_gpio;
196 	struct phy *phy;
197 };
198 
199 static inline void advk_writel(struct advk_pcie *pcie, u32 val, u64 reg)
200 {
201 	writel(val, pcie->base + reg);
202 }
203 
204 static inline u32 advk_readl(struct advk_pcie *pcie, u64 reg)
205 {
206 	return readl(pcie->base + reg);
207 }
208 
209 static inline u16 advk_read16(struct advk_pcie *pcie, u64 reg)
210 {
211 	return advk_readl(pcie, (reg & ~0x3)) >> ((reg & 0x3) * 8);
212 }
213 
214 static int advk_pcie_link_up(struct advk_pcie *pcie)
215 {
216 	u32 val, ltssm_state;
217 
218 	val = advk_readl(pcie, CFG_REG);
219 	ltssm_state = (val >> LTSSM_SHIFT) & LTSSM_MASK;
220 	return ltssm_state >= LTSSM_L0;
221 }
222 
223 static int advk_pcie_wait_for_link(struct advk_pcie *pcie)
224 {
225 	int retries;
226 
227 	/* check if the link is up or not */
228 	for (retries = 0; retries < LINK_WAIT_MAX_RETRIES; retries++) {
229 		if (advk_pcie_link_up(pcie))
230 			return 0;
231 
232 		usleep_range(LINK_WAIT_USLEEP_MIN, LINK_WAIT_USLEEP_MAX);
233 	}
234 
235 	return -ETIMEDOUT;
236 }
237 
238 static void advk_pcie_wait_for_retrain(struct advk_pcie *pcie)
239 {
240 	size_t retries;
241 
242 	for (retries = 0; retries < RETRAIN_WAIT_MAX_RETRIES; ++retries) {
243 		if (!advk_pcie_link_up(pcie))
244 			break;
245 		udelay(RETRAIN_WAIT_USLEEP_US);
246 	}
247 }
248 
249 static void advk_pcie_issue_perst(struct advk_pcie *pcie)
250 {
251 	u32 reg;
252 
253 	if (!pcie->reset_gpio)
254 		return;
255 
256 	/*
257 	 * As required by PCI Express spec (PCI Express Base Specification, REV.
258 	 * 4.0 PCI Express, February 19 2014, 6.6.1 Conventional Reset) a delay
259 	 * for at least 100ms after de-asserting PERST# signal is needed before
260 	 * link training is enabled. So ensure that link training is disabled
261 	 * prior de-asserting PERST# signal to fulfill that PCI Express spec
262 	 * requirement.
263 	 */
264 	reg = advk_readl(pcie, PCIE_CORE_CTRL0_REG);
265 	reg &= ~LINK_TRAINING_EN;
266 	advk_writel(pcie, reg, PCIE_CORE_CTRL0_REG);
267 
268 	/* 10ms delay is needed for some cards */
269 	dev_info(&pcie->pdev->dev, "issuing PERST via reset GPIO for 10ms\n");
270 	gpiod_set_value_cansleep(pcie->reset_gpio, 1);
271 	usleep_range(10000, 11000);
272 	gpiod_set_value_cansleep(pcie->reset_gpio, 0);
273 }
274 
275 static int advk_pcie_train_at_gen(struct advk_pcie *pcie, int gen)
276 {
277 	int ret, neg_gen;
278 	u32 reg;
279 
280 	/* Setup link speed */
281 	reg = advk_readl(pcie, PCIE_CORE_CTRL0_REG);
282 	reg &= ~PCIE_GEN_SEL_MSK;
283 	if (gen == 3)
284 		reg |= SPEED_GEN_3;
285 	else if (gen == 2)
286 		reg |= SPEED_GEN_2;
287 	else
288 		reg |= SPEED_GEN_1;
289 	advk_writel(pcie, reg, PCIE_CORE_CTRL0_REG);
290 
291 	/*
292 	 * Enable link training. This is not needed in every call to this
293 	 * function, just once suffices, but it does not break anything either.
294 	 */
295 	reg = advk_readl(pcie, PCIE_CORE_CTRL0_REG);
296 	reg |= LINK_TRAINING_EN;
297 	advk_writel(pcie, reg, PCIE_CORE_CTRL0_REG);
298 
299 	/*
300 	 * Start link training immediately after enabling it.
301 	 * This solves problems for some buggy cards.
302 	 */
303 	reg = advk_readl(pcie, PCIE_CORE_PCIEXP_CAP + PCI_EXP_LNKCTL);
304 	reg |= PCI_EXP_LNKCTL_RL;
305 	advk_writel(pcie, reg, PCIE_CORE_PCIEXP_CAP + PCI_EXP_LNKCTL);
306 
307 	ret = advk_pcie_wait_for_link(pcie);
308 	if (ret)
309 		return ret;
310 
311 	reg = advk_read16(pcie, PCIE_CORE_PCIEXP_CAP + PCI_EXP_LNKSTA);
312 	neg_gen = reg & PCI_EXP_LNKSTA_CLS;
313 
314 	return neg_gen;
315 }
316 
317 static void advk_pcie_train_link(struct advk_pcie *pcie)
318 {
319 	struct device *dev = &pcie->pdev->dev;
320 	int neg_gen = -1, gen;
321 
322 	/*
323 	 * Reset PCIe card via PERST# signal. Some cards are not detected
324 	 * during link training when they are in some non-initial state.
325 	 */
326 	advk_pcie_issue_perst(pcie);
327 
328 	/*
329 	 * PERST# signal could have been asserted by pinctrl subsystem before
330 	 * probe() callback has been called or issued explicitly by reset gpio
331 	 * function advk_pcie_issue_perst(), making the endpoint going into
332 	 * fundamental reset. As required by PCI Express spec a delay for at
333 	 * least 100ms after such a reset before link training is needed.
334 	 */
335 	msleep(PCI_PM_D3COLD_WAIT);
336 
337 	/*
338 	 * Try link training at link gen specified by device tree property
339 	 * 'max-link-speed'. If this fails, iteratively train at lower gen.
340 	 */
341 	for (gen = pcie->link_gen; gen > 0; --gen) {
342 		neg_gen = advk_pcie_train_at_gen(pcie, gen);
343 		if (neg_gen > 0)
344 			break;
345 	}
346 
347 	if (neg_gen < 0)
348 		goto err;
349 
350 	/*
351 	 * After successful training if negotiated gen is lower than requested,
352 	 * train again on negotiated gen. This solves some stability issues for
353 	 * some buggy gen1 cards.
354 	 */
355 	if (neg_gen < gen) {
356 		gen = neg_gen;
357 		neg_gen = advk_pcie_train_at_gen(pcie, gen);
358 	}
359 
360 	if (neg_gen == gen) {
361 		dev_info(dev, "link up at gen %i\n", gen);
362 		return;
363 	}
364 
365 err:
366 	dev_err(dev, "link never came up\n");
367 }
368 
369 static void advk_pcie_setup_hw(struct advk_pcie *pcie)
370 {
371 	u32 reg;
372 
373 	/* Enable TX */
374 	reg = advk_readl(pcie, PCIE_CORE_REF_CLK_REG);
375 	reg |= PCIE_CORE_REF_CLK_TX_ENABLE;
376 	advk_writel(pcie, reg, PCIE_CORE_REF_CLK_REG);
377 
378 	/* Set to Direct mode */
379 	reg = advk_readl(pcie, CTRL_CONFIG_REG);
380 	reg &= ~(CTRL_MODE_MASK << CTRL_MODE_SHIFT);
381 	reg |= ((PCIE_CORE_MODE_DIRECT & CTRL_MODE_MASK) << CTRL_MODE_SHIFT);
382 	advk_writel(pcie, reg, CTRL_CONFIG_REG);
383 
384 	/* Set PCI global control register to RC mode */
385 	reg = advk_readl(pcie, PCIE_CORE_CTRL0_REG);
386 	reg |= (IS_RC_MSK << IS_RC_SHIFT);
387 	advk_writel(pcie, reg, PCIE_CORE_CTRL0_REG);
388 
389 	/*
390 	 * Replace incorrect PCI vendor id value 0x1b4b by correct value 0x11ab.
391 	 * VENDOR_ID_REG contains vendor id in low 16 bits and subsystem vendor
392 	 * id in high 16 bits. Updating this register changes readback value of
393 	 * read-only vendor id bits in PCIE_CORE_DEV_ID_REG register. Workaround
394 	 * for erratum 4.1: "The value of device and vendor ID is incorrect".
395 	 */
396 	reg = (PCI_VENDOR_ID_MARVELL << 16) | PCI_VENDOR_ID_MARVELL;
397 	advk_writel(pcie, reg, VENDOR_ID_REG);
398 
399 	/* Set Advanced Error Capabilities and Control PF0 register */
400 	reg = PCIE_CORE_ERR_CAPCTL_ECRC_CHK_TX |
401 		PCIE_CORE_ERR_CAPCTL_ECRC_CHK_TX_EN |
402 		PCIE_CORE_ERR_CAPCTL_ECRC_CHCK |
403 		PCIE_CORE_ERR_CAPCTL_ECRC_CHCK_RCV;
404 	advk_writel(pcie, reg, PCIE_CORE_ERR_CAPCTL_REG);
405 
406 	/* Set PCIe Device Control register */
407 	reg = advk_readl(pcie, PCIE_CORE_PCIEXP_CAP + PCI_EXP_DEVCTL);
408 	reg &= ~PCI_EXP_DEVCTL_RELAX_EN;
409 	reg &= ~PCI_EXP_DEVCTL_NOSNOOP_EN;
410 	reg &= ~PCI_EXP_DEVCTL_READRQ;
411 	reg |= PCI_EXP_DEVCTL_PAYLOAD; /* Set max payload size */
412 	reg |= PCI_EXP_DEVCTL_READRQ_512B;
413 	advk_writel(pcie, reg, PCIE_CORE_PCIEXP_CAP + PCI_EXP_DEVCTL);
414 
415 	/* Program PCIe Control 2 to disable strict ordering */
416 	reg = PCIE_CORE_CTRL2_RESERVED |
417 		PCIE_CORE_CTRL2_TD_ENABLE;
418 	advk_writel(pcie, reg, PCIE_CORE_CTRL2_REG);
419 
420 	/* Set lane X1 */
421 	reg = advk_readl(pcie, PCIE_CORE_CTRL0_REG);
422 	reg &= ~LANE_CNT_MSK;
423 	reg |= LANE_COUNT_1;
424 	advk_writel(pcie, reg, PCIE_CORE_CTRL0_REG);
425 
426 	/* Enable MSI */
427 	reg = advk_readl(pcie, PCIE_CORE_CTRL2_REG);
428 	reg |= PCIE_CORE_CTRL2_MSI_ENABLE;
429 	advk_writel(pcie, reg, PCIE_CORE_CTRL2_REG);
430 
431 	/* Clear all interrupts */
432 	advk_writel(pcie, PCIE_ISR0_ALL_MASK, PCIE_ISR0_REG);
433 	advk_writel(pcie, PCIE_ISR1_ALL_MASK, PCIE_ISR1_REG);
434 	advk_writel(pcie, PCIE_IRQ_ALL_MASK, HOST_CTRL_INT_STATUS_REG);
435 
436 	/* Disable All ISR0/1 Sources */
437 	reg = PCIE_ISR0_ALL_MASK;
438 	reg &= ~PCIE_ISR0_MSI_INT_PENDING;
439 	advk_writel(pcie, reg, PCIE_ISR0_MASK_REG);
440 
441 	advk_writel(pcie, PCIE_ISR1_ALL_MASK, PCIE_ISR1_MASK_REG);
442 
443 	/* Unmask all MSIs */
444 	advk_writel(pcie, 0, PCIE_MSI_MASK_REG);
445 
446 	/* Enable summary interrupt for GIC SPI source */
447 	reg = PCIE_IRQ_ALL_MASK & (~PCIE_IRQ_ENABLE_INTS_MASK);
448 	advk_writel(pcie, reg, HOST_CTRL_INT_MASK_REG);
449 
450 	reg = advk_readl(pcie, PCIE_CORE_CTRL2_REG);
451 	reg |= PCIE_CORE_CTRL2_OB_WIN_ENABLE;
452 	advk_writel(pcie, reg, PCIE_CORE_CTRL2_REG);
453 
454 	/* Bypass the address window mapping for PIO */
455 	reg = advk_readl(pcie, PIO_CTRL);
456 	reg |= PIO_CTRL_ADDR_WIN_DISABLE;
457 	advk_writel(pcie, reg, PIO_CTRL);
458 
459 	advk_pcie_train_link(pcie);
460 
461 	/*
462 	 * FIXME: The following register update is suspicious. This register is
463 	 * applicable only when the PCI controller is configured for Endpoint
464 	 * mode, not as a Root Complex. But apparently when this code is
465 	 * removed, some cards stop working. This should be investigated and
466 	 * a comment explaining this should be put here.
467 	 */
468 	reg = advk_readl(pcie, PCIE_CORE_CMD_STATUS_REG);
469 	reg |= PCIE_CORE_CMD_MEM_ACCESS_EN |
470 		PCIE_CORE_CMD_IO_ACCESS_EN |
471 		PCIE_CORE_CMD_MEM_IO_REQ_EN;
472 	advk_writel(pcie, reg, PCIE_CORE_CMD_STATUS_REG);
473 }
474 
475 static void advk_pcie_check_pio_status(struct advk_pcie *pcie)
476 {
477 	struct device *dev = &pcie->pdev->dev;
478 	u32 reg;
479 	unsigned int status;
480 	char *strcomp_status, *str_posted;
481 
482 	reg = advk_readl(pcie, PIO_STAT);
483 	status = (reg & PIO_COMPLETION_STATUS_MASK) >>
484 		PIO_COMPLETION_STATUS_SHIFT;
485 
486 	if (!status)
487 		return;
488 
489 	switch (status) {
490 	case PIO_COMPLETION_STATUS_UR:
491 		strcomp_status = "UR";
492 		break;
493 	case PIO_COMPLETION_STATUS_CRS:
494 		strcomp_status = "CRS";
495 		break;
496 	case PIO_COMPLETION_STATUS_CA:
497 		strcomp_status = "CA";
498 		break;
499 	default:
500 		strcomp_status = "Unknown";
501 		break;
502 	}
503 
504 	if (reg & PIO_NON_POSTED_REQ)
505 		str_posted = "Non-posted";
506 	else
507 		str_posted = "Posted";
508 
509 	dev_err(dev, "%s PIO Response Status: %s, %#x @ %#x\n",
510 		str_posted, strcomp_status, reg, advk_readl(pcie, PIO_ADDR_LS));
511 }
512 
513 static int advk_pcie_wait_pio(struct advk_pcie *pcie)
514 {
515 	struct device *dev = &pcie->pdev->dev;
516 	int i;
517 
518 	for (i = 0; i < PIO_RETRY_CNT; i++) {
519 		u32 start, isr;
520 
521 		start = advk_readl(pcie, PIO_START);
522 		isr = advk_readl(pcie, PIO_ISR);
523 		if (!start && isr)
524 			return 0;
525 		udelay(PIO_RETRY_DELAY);
526 	}
527 
528 	dev_err(dev, "PIO read/write transfer time out\n");
529 	return -ETIMEDOUT;
530 }
531 
532 
533 static pci_bridge_emul_read_status_t
534 advk_pci_bridge_emul_pcie_conf_read(struct pci_bridge_emul *bridge,
535 				    int reg, u32 *value)
536 {
537 	struct advk_pcie *pcie = bridge->data;
538 
539 
540 	switch (reg) {
541 	case PCI_EXP_SLTCTL:
542 		*value = PCI_EXP_SLTSTA_PDS << 16;
543 		return PCI_BRIDGE_EMUL_HANDLED;
544 
545 	case PCI_EXP_RTCTL: {
546 		u32 val = advk_readl(pcie, PCIE_ISR0_MASK_REG);
547 		*value = (val & PCIE_MSG_PM_PME_MASK) ? 0 : PCI_EXP_RTCTL_PMEIE;
548 		return PCI_BRIDGE_EMUL_HANDLED;
549 	}
550 
551 	case PCI_EXP_RTSTA: {
552 		u32 isr0 = advk_readl(pcie, PCIE_ISR0_REG);
553 		u32 msglog = advk_readl(pcie, PCIE_MSG_LOG_REG);
554 		*value = (isr0 & PCIE_MSG_PM_PME_MASK) << 16 | (msglog >> 16);
555 		return PCI_BRIDGE_EMUL_HANDLED;
556 	}
557 
558 	case PCI_EXP_LNKCTL: {
559 		/* u32 contains both PCI_EXP_LNKCTL and PCI_EXP_LNKSTA */
560 		u32 val = advk_readl(pcie, PCIE_CORE_PCIEXP_CAP + reg) &
561 			~(PCI_EXP_LNKSTA_LT << 16);
562 		if (!advk_pcie_link_up(pcie))
563 			val |= (PCI_EXP_LNKSTA_LT << 16);
564 		*value = val;
565 		return PCI_BRIDGE_EMUL_HANDLED;
566 	}
567 
568 	case PCI_CAP_LIST_ID:
569 	case PCI_EXP_DEVCAP:
570 	case PCI_EXP_DEVCTL:
571 	case PCI_EXP_LNKCAP:
572 		*value = advk_readl(pcie, PCIE_CORE_PCIEXP_CAP + reg);
573 		return PCI_BRIDGE_EMUL_HANDLED;
574 	default:
575 		return PCI_BRIDGE_EMUL_NOT_HANDLED;
576 	}
577 
578 }
579 
580 static void
581 advk_pci_bridge_emul_pcie_conf_write(struct pci_bridge_emul *bridge,
582 				     int reg, u32 old, u32 new, u32 mask)
583 {
584 	struct advk_pcie *pcie = bridge->data;
585 
586 	switch (reg) {
587 	case PCI_EXP_DEVCTL:
588 		advk_writel(pcie, new, PCIE_CORE_PCIEXP_CAP + reg);
589 		break;
590 
591 	case PCI_EXP_LNKCTL:
592 		advk_writel(pcie, new, PCIE_CORE_PCIEXP_CAP + reg);
593 		if (new & PCI_EXP_LNKCTL_RL)
594 			advk_pcie_wait_for_retrain(pcie);
595 		break;
596 
597 	case PCI_EXP_RTCTL: {
598 		/* Only mask/unmask PME interrupt */
599 		u32 val = advk_readl(pcie, PCIE_ISR0_MASK_REG) &
600 			~PCIE_MSG_PM_PME_MASK;
601 		if ((new & PCI_EXP_RTCTL_PMEIE) == 0)
602 			val |= PCIE_MSG_PM_PME_MASK;
603 		advk_writel(pcie, val, PCIE_ISR0_MASK_REG);
604 		break;
605 	}
606 
607 	case PCI_EXP_RTSTA:
608 		new = (new & PCI_EXP_RTSTA_PME) >> 9;
609 		advk_writel(pcie, new, PCIE_ISR0_REG);
610 		break;
611 
612 	default:
613 		break;
614 	}
615 }
616 
617 static struct pci_bridge_emul_ops advk_pci_bridge_emul_ops = {
618 	.read_pcie = advk_pci_bridge_emul_pcie_conf_read,
619 	.write_pcie = advk_pci_bridge_emul_pcie_conf_write,
620 };
621 
622 /*
623  * Initialize the configuration space of the PCI-to-PCI bridge
624  * associated with the given PCIe interface.
625  */
626 static int advk_sw_pci_bridge_init(struct advk_pcie *pcie)
627 {
628 	struct pci_bridge_emul *bridge = &pcie->bridge;
629 
630 	bridge->conf.vendor =
631 		cpu_to_le16(advk_readl(pcie, PCIE_CORE_DEV_ID_REG) & 0xffff);
632 	bridge->conf.device =
633 		cpu_to_le16(advk_readl(pcie, PCIE_CORE_DEV_ID_REG) >> 16);
634 	bridge->conf.class_revision =
635 		cpu_to_le32(advk_readl(pcie, PCIE_CORE_DEV_REV_REG) & 0xff);
636 
637 	/* Support 32 bits I/O addressing */
638 	bridge->conf.iobase = PCI_IO_RANGE_TYPE_32;
639 	bridge->conf.iolimit = PCI_IO_RANGE_TYPE_32;
640 
641 	/* Support 64 bits memory pref */
642 	bridge->conf.pref_mem_base = cpu_to_le16(PCI_PREF_RANGE_TYPE_64);
643 	bridge->conf.pref_mem_limit = cpu_to_le16(PCI_PREF_RANGE_TYPE_64);
644 
645 	/* Support interrupt A for MSI feature */
646 	bridge->conf.intpin = PCIE_CORE_INT_A_ASSERT_ENABLE;
647 
648 	bridge->has_pcie = true;
649 	bridge->data = pcie;
650 	bridge->ops = &advk_pci_bridge_emul_ops;
651 
652 	return pci_bridge_emul_init(bridge, 0);
653 }
654 
655 static bool advk_pcie_valid_device(struct advk_pcie *pcie, struct pci_bus *bus,
656 				  int devfn)
657 {
658 	if (pci_is_root_bus(bus) && PCI_SLOT(devfn) != 0)
659 		return false;
660 
661 	/*
662 	 * If the link goes down after we check for link-up, nothing bad
663 	 * happens but the config access times out.
664 	 */
665 	if (!pci_is_root_bus(bus) && !advk_pcie_link_up(pcie))
666 		return false;
667 
668 	return true;
669 }
670 
671 static bool advk_pcie_pio_is_running(struct advk_pcie *pcie)
672 {
673 	struct device *dev = &pcie->pdev->dev;
674 
675 	/*
676 	 * Trying to start a new PIO transfer when previous has not completed
677 	 * cause External Abort on CPU which results in kernel panic:
678 	 *
679 	 *     SError Interrupt on CPU0, code 0xbf000002 -- SError
680 	 *     Kernel panic - not syncing: Asynchronous SError Interrupt
681 	 *
682 	 * Functions advk_pcie_rd_conf() and advk_pcie_wr_conf() are protected
683 	 * by raw_spin_lock_irqsave() at pci_lock_config() level to prevent
684 	 * concurrent calls at the same time. But because PIO transfer may take
685 	 * about 1.5s when link is down or card is disconnected, it means that
686 	 * advk_pcie_wait_pio() does not always have to wait for completion.
687 	 *
688 	 * Some versions of ARM Trusted Firmware handles this External Abort at
689 	 * EL3 level and mask it to prevent kernel panic. Relevant TF-A commit:
690 	 * https://git.trustedfirmware.org/TF-A/trusted-firmware-a.git/commit/?id=3c7dcdac5c50
691 	 */
692 	if (advk_readl(pcie, PIO_START)) {
693 		dev_err(dev, "Previous PIO read/write transfer is still running\n");
694 		return true;
695 	}
696 
697 	return false;
698 }
699 
700 static int advk_pcie_rd_conf(struct pci_bus *bus, u32 devfn,
701 			     int where, int size, u32 *val)
702 {
703 	struct advk_pcie *pcie = bus->sysdata;
704 	u32 reg;
705 	int ret;
706 
707 	if (!advk_pcie_valid_device(pcie, bus, devfn)) {
708 		*val = 0xffffffff;
709 		return PCIBIOS_DEVICE_NOT_FOUND;
710 	}
711 
712 	if (pci_is_root_bus(bus))
713 		return pci_bridge_emul_conf_read(&pcie->bridge, where,
714 						 size, val);
715 
716 	if (advk_pcie_pio_is_running(pcie)) {
717 		*val = 0xffffffff;
718 		return PCIBIOS_SET_FAILED;
719 	}
720 
721 	/* Program the control register */
722 	reg = advk_readl(pcie, PIO_CTRL);
723 	reg &= ~PIO_CTRL_TYPE_MASK;
724 	if (pci_is_root_bus(bus->parent))
725 		reg |= PCIE_CONFIG_RD_TYPE0;
726 	else
727 		reg |= PCIE_CONFIG_RD_TYPE1;
728 	advk_writel(pcie, reg, PIO_CTRL);
729 
730 	/* Program the address registers */
731 	reg = ALIGN_DOWN(PCIE_ECAM_OFFSET(bus->number, devfn, where), 4);
732 	advk_writel(pcie, reg, PIO_ADDR_LS);
733 	advk_writel(pcie, 0, PIO_ADDR_MS);
734 
735 	/* Program the data strobe */
736 	advk_writel(pcie, 0xf, PIO_WR_DATA_STRB);
737 
738 	/* Clear PIO DONE ISR and start the transfer */
739 	advk_writel(pcie, 1, PIO_ISR);
740 	advk_writel(pcie, 1, PIO_START);
741 
742 	ret = advk_pcie_wait_pio(pcie);
743 	if (ret < 0) {
744 		*val = 0xffffffff;
745 		return PCIBIOS_SET_FAILED;
746 	}
747 
748 	advk_pcie_check_pio_status(pcie);
749 
750 	/* Get the read result */
751 	*val = advk_readl(pcie, PIO_RD_DATA);
752 	if (size == 1)
753 		*val = (*val >> (8 * (where & 3))) & 0xff;
754 	else if (size == 2)
755 		*val = (*val >> (8 * (where & 3))) & 0xffff;
756 
757 	return PCIBIOS_SUCCESSFUL;
758 }
759 
760 static int advk_pcie_wr_conf(struct pci_bus *bus, u32 devfn,
761 				int where, int size, u32 val)
762 {
763 	struct advk_pcie *pcie = bus->sysdata;
764 	u32 reg;
765 	u32 data_strobe = 0x0;
766 	int offset;
767 	int ret;
768 
769 	if (!advk_pcie_valid_device(pcie, bus, devfn))
770 		return PCIBIOS_DEVICE_NOT_FOUND;
771 
772 	if (pci_is_root_bus(bus))
773 		return pci_bridge_emul_conf_write(&pcie->bridge, where,
774 						  size, val);
775 
776 	if (where % size)
777 		return PCIBIOS_SET_FAILED;
778 
779 	if (advk_pcie_pio_is_running(pcie))
780 		return PCIBIOS_SET_FAILED;
781 
782 	/* Program the control register */
783 	reg = advk_readl(pcie, PIO_CTRL);
784 	reg &= ~PIO_CTRL_TYPE_MASK;
785 	if (pci_is_root_bus(bus->parent))
786 		reg |= PCIE_CONFIG_WR_TYPE0;
787 	else
788 		reg |= PCIE_CONFIG_WR_TYPE1;
789 	advk_writel(pcie, reg, PIO_CTRL);
790 
791 	/* Program the address registers */
792 	reg = ALIGN_DOWN(PCIE_ECAM_OFFSET(bus->number, devfn, where), 4);
793 	advk_writel(pcie, reg, PIO_ADDR_LS);
794 	advk_writel(pcie, 0, PIO_ADDR_MS);
795 
796 	/* Calculate the write strobe */
797 	offset      = where & 0x3;
798 	reg         = val << (8 * offset);
799 	data_strobe = GENMASK(size - 1, 0) << offset;
800 
801 	/* Program the data register */
802 	advk_writel(pcie, reg, PIO_WR_DATA);
803 
804 	/* Program the data strobe */
805 	advk_writel(pcie, data_strobe, PIO_WR_DATA_STRB);
806 
807 	/* Clear PIO DONE ISR and start the transfer */
808 	advk_writel(pcie, 1, PIO_ISR);
809 	advk_writel(pcie, 1, PIO_START);
810 
811 	ret = advk_pcie_wait_pio(pcie);
812 	if (ret < 0)
813 		return PCIBIOS_SET_FAILED;
814 
815 	advk_pcie_check_pio_status(pcie);
816 
817 	return PCIBIOS_SUCCESSFUL;
818 }
819 
820 static struct pci_ops advk_pcie_ops = {
821 	.read = advk_pcie_rd_conf,
822 	.write = advk_pcie_wr_conf,
823 };
824 
825 static void advk_msi_irq_compose_msi_msg(struct irq_data *data,
826 					 struct msi_msg *msg)
827 {
828 	struct advk_pcie *pcie = irq_data_get_irq_chip_data(data);
829 	phys_addr_t msi_msg = virt_to_phys(&pcie->msi_msg);
830 
831 	msg->address_lo = lower_32_bits(msi_msg);
832 	msg->address_hi = upper_32_bits(msi_msg);
833 	msg->data = data->irq;
834 }
835 
836 static int advk_msi_set_affinity(struct irq_data *irq_data,
837 				 const struct cpumask *mask, bool force)
838 {
839 	return -EINVAL;
840 }
841 
842 static int advk_msi_irq_domain_alloc(struct irq_domain *domain,
843 				     unsigned int virq,
844 				     unsigned int nr_irqs, void *args)
845 {
846 	struct advk_pcie *pcie = domain->host_data;
847 	int hwirq, i;
848 
849 	mutex_lock(&pcie->msi_used_lock);
850 	hwirq = bitmap_find_next_zero_area(pcie->msi_used, MSI_IRQ_NUM,
851 					   0, nr_irqs, 0);
852 	if (hwirq >= MSI_IRQ_NUM) {
853 		mutex_unlock(&pcie->msi_used_lock);
854 		return -ENOSPC;
855 	}
856 
857 	bitmap_set(pcie->msi_used, hwirq, nr_irqs);
858 	mutex_unlock(&pcie->msi_used_lock);
859 
860 	for (i = 0; i < nr_irqs; i++)
861 		irq_domain_set_info(domain, virq + i, hwirq + i,
862 				    &pcie->msi_bottom_irq_chip,
863 				    domain->host_data, handle_simple_irq,
864 				    NULL, NULL);
865 
866 	return hwirq;
867 }
868 
869 static void advk_msi_irq_domain_free(struct irq_domain *domain,
870 				     unsigned int virq, unsigned int nr_irqs)
871 {
872 	struct irq_data *d = irq_domain_get_irq_data(domain, virq);
873 	struct advk_pcie *pcie = domain->host_data;
874 
875 	mutex_lock(&pcie->msi_used_lock);
876 	bitmap_clear(pcie->msi_used, d->hwirq, nr_irqs);
877 	mutex_unlock(&pcie->msi_used_lock);
878 }
879 
880 static const struct irq_domain_ops advk_msi_domain_ops = {
881 	.alloc = advk_msi_irq_domain_alloc,
882 	.free = advk_msi_irq_domain_free,
883 };
884 
885 static void advk_pcie_irq_mask(struct irq_data *d)
886 {
887 	struct advk_pcie *pcie = d->domain->host_data;
888 	irq_hw_number_t hwirq = irqd_to_hwirq(d);
889 	u32 mask;
890 
891 	mask = advk_readl(pcie, PCIE_ISR1_MASK_REG);
892 	mask |= PCIE_ISR1_INTX_ASSERT(hwirq);
893 	advk_writel(pcie, mask, PCIE_ISR1_MASK_REG);
894 }
895 
896 static void advk_pcie_irq_unmask(struct irq_data *d)
897 {
898 	struct advk_pcie *pcie = d->domain->host_data;
899 	irq_hw_number_t hwirq = irqd_to_hwirq(d);
900 	u32 mask;
901 
902 	mask = advk_readl(pcie, PCIE_ISR1_MASK_REG);
903 	mask &= ~PCIE_ISR1_INTX_ASSERT(hwirq);
904 	advk_writel(pcie, mask, PCIE_ISR1_MASK_REG);
905 }
906 
907 static int advk_pcie_irq_map(struct irq_domain *h,
908 			     unsigned int virq, irq_hw_number_t hwirq)
909 {
910 	struct advk_pcie *pcie = h->host_data;
911 
912 	advk_pcie_irq_mask(irq_get_irq_data(virq));
913 	irq_set_status_flags(virq, IRQ_LEVEL);
914 	irq_set_chip_and_handler(virq, &pcie->irq_chip,
915 				 handle_level_irq);
916 	irq_set_chip_data(virq, pcie);
917 
918 	return 0;
919 }
920 
921 static const struct irq_domain_ops advk_pcie_irq_domain_ops = {
922 	.map = advk_pcie_irq_map,
923 	.xlate = irq_domain_xlate_onecell,
924 };
925 
926 static int advk_pcie_init_msi_irq_domain(struct advk_pcie *pcie)
927 {
928 	struct device *dev = &pcie->pdev->dev;
929 	struct device_node *node = dev->of_node;
930 	struct irq_chip *bottom_ic, *msi_ic;
931 	struct msi_domain_info *msi_di;
932 	phys_addr_t msi_msg_phys;
933 
934 	mutex_init(&pcie->msi_used_lock);
935 
936 	bottom_ic = &pcie->msi_bottom_irq_chip;
937 
938 	bottom_ic->name = "MSI";
939 	bottom_ic->irq_compose_msi_msg = advk_msi_irq_compose_msi_msg;
940 	bottom_ic->irq_set_affinity = advk_msi_set_affinity;
941 
942 	msi_ic = &pcie->msi_irq_chip;
943 	msi_ic->name = "advk-MSI";
944 
945 	msi_di = &pcie->msi_domain_info;
946 	msi_di->flags = MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
947 		MSI_FLAG_MULTI_PCI_MSI;
948 	msi_di->chip = msi_ic;
949 
950 	msi_msg_phys = virt_to_phys(&pcie->msi_msg);
951 
952 	advk_writel(pcie, lower_32_bits(msi_msg_phys),
953 		    PCIE_MSI_ADDR_LOW_REG);
954 	advk_writel(pcie, upper_32_bits(msi_msg_phys),
955 		    PCIE_MSI_ADDR_HIGH_REG);
956 
957 	pcie->msi_inner_domain =
958 		irq_domain_add_linear(NULL, MSI_IRQ_NUM,
959 				      &advk_msi_domain_ops, pcie);
960 	if (!pcie->msi_inner_domain)
961 		return -ENOMEM;
962 
963 	pcie->msi_domain =
964 		pci_msi_create_irq_domain(of_node_to_fwnode(node),
965 					  msi_di, pcie->msi_inner_domain);
966 	if (!pcie->msi_domain) {
967 		irq_domain_remove(pcie->msi_inner_domain);
968 		return -ENOMEM;
969 	}
970 
971 	return 0;
972 }
973 
974 static void advk_pcie_remove_msi_irq_domain(struct advk_pcie *pcie)
975 {
976 	irq_domain_remove(pcie->msi_domain);
977 	irq_domain_remove(pcie->msi_inner_domain);
978 }
979 
980 static int advk_pcie_init_irq_domain(struct advk_pcie *pcie)
981 {
982 	struct device *dev = &pcie->pdev->dev;
983 	struct device_node *node = dev->of_node;
984 	struct device_node *pcie_intc_node;
985 	struct irq_chip *irq_chip;
986 	int ret = 0;
987 
988 	pcie_intc_node =  of_get_next_child(node, NULL);
989 	if (!pcie_intc_node) {
990 		dev_err(dev, "No PCIe Intc node found\n");
991 		return -ENODEV;
992 	}
993 
994 	irq_chip = &pcie->irq_chip;
995 
996 	irq_chip->name = devm_kasprintf(dev, GFP_KERNEL, "%s-irq",
997 					dev_name(dev));
998 	if (!irq_chip->name) {
999 		ret = -ENOMEM;
1000 		goto out_put_node;
1001 	}
1002 
1003 	irq_chip->irq_mask = advk_pcie_irq_mask;
1004 	irq_chip->irq_mask_ack = advk_pcie_irq_mask;
1005 	irq_chip->irq_unmask = advk_pcie_irq_unmask;
1006 
1007 	pcie->irq_domain =
1008 		irq_domain_add_linear(pcie_intc_node, PCI_NUM_INTX,
1009 				      &advk_pcie_irq_domain_ops, pcie);
1010 	if (!pcie->irq_domain) {
1011 		dev_err(dev, "Failed to get a INTx IRQ domain\n");
1012 		ret = -ENOMEM;
1013 		goto out_put_node;
1014 	}
1015 
1016 out_put_node:
1017 	of_node_put(pcie_intc_node);
1018 	return ret;
1019 }
1020 
1021 static void advk_pcie_remove_irq_domain(struct advk_pcie *pcie)
1022 {
1023 	irq_domain_remove(pcie->irq_domain);
1024 }
1025 
1026 static void advk_pcie_handle_msi(struct advk_pcie *pcie)
1027 {
1028 	u32 msi_val, msi_mask, msi_status, msi_idx;
1029 	u16 msi_data;
1030 
1031 	msi_mask = advk_readl(pcie, PCIE_MSI_MASK_REG);
1032 	msi_val = advk_readl(pcie, PCIE_MSI_STATUS_REG);
1033 	msi_status = msi_val & ~msi_mask;
1034 
1035 	for (msi_idx = 0; msi_idx < MSI_IRQ_NUM; msi_idx++) {
1036 		if (!(BIT(msi_idx) & msi_status))
1037 			continue;
1038 
1039 		advk_writel(pcie, BIT(msi_idx), PCIE_MSI_STATUS_REG);
1040 		msi_data = advk_readl(pcie, PCIE_MSI_PAYLOAD_REG) & 0xFF;
1041 		generic_handle_irq(msi_data);
1042 	}
1043 
1044 	advk_writel(pcie, PCIE_ISR0_MSI_INT_PENDING,
1045 		    PCIE_ISR0_REG);
1046 }
1047 
1048 static void advk_pcie_handle_int(struct advk_pcie *pcie)
1049 {
1050 	u32 isr0_val, isr0_mask, isr0_status;
1051 	u32 isr1_val, isr1_mask, isr1_status;
1052 	int i, virq;
1053 
1054 	isr0_val = advk_readl(pcie, PCIE_ISR0_REG);
1055 	isr0_mask = advk_readl(pcie, PCIE_ISR0_MASK_REG);
1056 	isr0_status = isr0_val & ((~isr0_mask) & PCIE_ISR0_ALL_MASK);
1057 
1058 	isr1_val = advk_readl(pcie, PCIE_ISR1_REG);
1059 	isr1_mask = advk_readl(pcie, PCIE_ISR1_MASK_REG);
1060 	isr1_status = isr1_val & ((~isr1_mask) & PCIE_ISR1_ALL_MASK);
1061 
1062 	if (!isr0_status && !isr1_status) {
1063 		advk_writel(pcie, isr0_val, PCIE_ISR0_REG);
1064 		advk_writel(pcie, isr1_val, PCIE_ISR1_REG);
1065 		return;
1066 	}
1067 
1068 	/* Process MSI interrupts */
1069 	if (isr0_status & PCIE_ISR0_MSI_INT_PENDING)
1070 		advk_pcie_handle_msi(pcie);
1071 
1072 	/* Process legacy interrupts */
1073 	for (i = 0; i < PCI_NUM_INTX; i++) {
1074 		if (!(isr1_status & PCIE_ISR1_INTX_ASSERT(i)))
1075 			continue;
1076 
1077 		advk_writel(pcie, PCIE_ISR1_INTX_ASSERT(i),
1078 			    PCIE_ISR1_REG);
1079 
1080 		virq = irq_find_mapping(pcie->irq_domain, i);
1081 		generic_handle_irq(virq);
1082 	}
1083 }
1084 
1085 static irqreturn_t advk_pcie_irq_handler(int irq, void *arg)
1086 {
1087 	struct advk_pcie *pcie = arg;
1088 	u32 status;
1089 
1090 	status = advk_readl(pcie, HOST_CTRL_INT_STATUS_REG);
1091 	if (!(status & PCIE_IRQ_CORE_INT))
1092 		return IRQ_NONE;
1093 
1094 	advk_pcie_handle_int(pcie);
1095 
1096 	/* Clear interrupt */
1097 	advk_writel(pcie, PCIE_IRQ_CORE_INT, HOST_CTRL_INT_STATUS_REG);
1098 
1099 	return IRQ_HANDLED;
1100 }
1101 
1102 static void __maybe_unused advk_pcie_disable_phy(struct advk_pcie *pcie)
1103 {
1104 	phy_power_off(pcie->phy);
1105 	phy_exit(pcie->phy);
1106 }
1107 
1108 static int advk_pcie_enable_phy(struct advk_pcie *pcie)
1109 {
1110 	int ret;
1111 
1112 	if (!pcie->phy)
1113 		return 0;
1114 
1115 	ret = phy_init(pcie->phy);
1116 	if (ret)
1117 		return ret;
1118 
1119 	ret = phy_set_mode(pcie->phy, PHY_MODE_PCIE);
1120 	if (ret) {
1121 		phy_exit(pcie->phy);
1122 		return ret;
1123 	}
1124 
1125 	ret = phy_power_on(pcie->phy);
1126 	if (ret == -EOPNOTSUPP) {
1127 		dev_warn(&pcie->pdev->dev, "PHY unsupported by firmware\n");
1128 	} else if (ret) {
1129 		phy_exit(pcie->phy);
1130 		return ret;
1131 	}
1132 
1133 	return 0;
1134 }
1135 
1136 static int advk_pcie_setup_phy(struct advk_pcie *pcie)
1137 {
1138 	struct device *dev = &pcie->pdev->dev;
1139 	struct device_node *node = dev->of_node;
1140 	int ret = 0;
1141 
1142 	pcie->phy = devm_of_phy_get(dev, node, NULL);
1143 	if (IS_ERR(pcie->phy) && (PTR_ERR(pcie->phy) == -EPROBE_DEFER))
1144 		return PTR_ERR(pcie->phy);
1145 
1146 	/* Old bindings miss the PHY handle */
1147 	if (IS_ERR(pcie->phy)) {
1148 		dev_warn(dev, "PHY unavailable (%ld)\n", PTR_ERR(pcie->phy));
1149 		pcie->phy = NULL;
1150 		return 0;
1151 	}
1152 
1153 	ret = advk_pcie_enable_phy(pcie);
1154 	if (ret)
1155 		dev_err(dev, "Failed to initialize PHY (%d)\n", ret);
1156 
1157 	return ret;
1158 }
1159 
1160 static int advk_pcie_probe(struct platform_device *pdev)
1161 {
1162 	struct device *dev = &pdev->dev;
1163 	struct advk_pcie *pcie;
1164 	struct pci_host_bridge *bridge;
1165 	int ret, irq;
1166 
1167 	bridge = devm_pci_alloc_host_bridge(dev, sizeof(struct advk_pcie));
1168 	if (!bridge)
1169 		return -ENOMEM;
1170 
1171 	pcie = pci_host_bridge_priv(bridge);
1172 	pcie->pdev = pdev;
1173 	platform_set_drvdata(pdev, pcie);
1174 
1175 	pcie->base = devm_platform_ioremap_resource(pdev, 0);
1176 	if (IS_ERR(pcie->base))
1177 		return PTR_ERR(pcie->base);
1178 
1179 	irq = platform_get_irq(pdev, 0);
1180 	if (irq < 0)
1181 		return irq;
1182 
1183 	ret = devm_request_irq(dev, irq, advk_pcie_irq_handler,
1184 			       IRQF_SHARED | IRQF_NO_THREAD, "advk-pcie",
1185 			       pcie);
1186 	if (ret) {
1187 		dev_err(dev, "Failed to register interrupt\n");
1188 		return ret;
1189 	}
1190 
1191 	pcie->reset_gpio = devm_gpiod_get_from_of_node(dev, dev->of_node,
1192 						       "reset-gpios", 0,
1193 						       GPIOD_OUT_LOW,
1194 						       "pcie1-reset");
1195 	ret = PTR_ERR_OR_ZERO(pcie->reset_gpio);
1196 	if (ret) {
1197 		if (ret == -ENOENT) {
1198 			pcie->reset_gpio = NULL;
1199 		} else {
1200 			if (ret != -EPROBE_DEFER)
1201 				dev_err(dev, "Failed to get reset-gpio: %i\n",
1202 					ret);
1203 			return ret;
1204 		}
1205 	}
1206 
1207 	ret = of_pci_get_max_link_speed(dev->of_node);
1208 	if (ret <= 0 || ret > 3)
1209 		pcie->link_gen = 3;
1210 	else
1211 		pcie->link_gen = ret;
1212 
1213 	ret = advk_pcie_setup_phy(pcie);
1214 	if (ret)
1215 		return ret;
1216 
1217 	advk_pcie_setup_hw(pcie);
1218 
1219 	ret = advk_sw_pci_bridge_init(pcie);
1220 	if (ret) {
1221 		dev_err(dev, "Failed to register emulated root PCI bridge\n");
1222 		return ret;
1223 	}
1224 
1225 	ret = advk_pcie_init_irq_domain(pcie);
1226 	if (ret) {
1227 		dev_err(dev, "Failed to initialize irq\n");
1228 		return ret;
1229 	}
1230 
1231 	ret = advk_pcie_init_msi_irq_domain(pcie);
1232 	if (ret) {
1233 		dev_err(dev, "Failed to initialize irq\n");
1234 		advk_pcie_remove_irq_domain(pcie);
1235 		return ret;
1236 	}
1237 
1238 	bridge->sysdata = pcie;
1239 	bridge->ops = &advk_pcie_ops;
1240 
1241 	ret = pci_host_probe(bridge);
1242 	if (ret < 0) {
1243 		advk_pcie_remove_msi_irq_domain(pcie);
1244 		advk_pcie_remove_irq_domain(pcie);
1245 		return ret;
1246 	}
1247 
1248 	return 0;
1249 }
1250 
1251 static int advk_pcie_remove(struct platform_device *pdev)
1252 {
1253 	struct advk_pcie *pcie = platform_get_drvdata(pdev);
1254 	struct pci_host_bridge *bridge = pci_host_bridge_from_priv(pcie);
1255 
1256 	pci_lock_rescan_remove();
1257 	pci_stop_root_bus(bridge->bus);
1258 	pci_remove_root_bus(bridge->bus);
1259 	pci_unlock_rescan_remove();
1260 
1261 	advk_pcie_remove_msi_irq_domain(pcie);
1262 	advk_pcie_remove_irq_domain(pcie);
1263 
1264 	return 0;
1265 }
1266 
1267 static const struct of_device_id advk_pcie_of_match_table[] = {
1268 	{ .compatible = "marvell,armada-3700-pcie", },
1269 	{},
1270 };
1271 MODULE_DEVICE_TABLE(of, advk_pcie_of_match_table);
1272 
1273 static struct platform_driver advk_pcie_driver = {
1274 	.driver = {
1275 		.name = "advk-pcie",
1276 		.of_match_table = advk_pcie_of_match_table,
1277 	},
1278 	.probe = advk_pcie_probe,
1279 	.remove = advk_pcie_remove,
1280 };
1281 module_platform_driver(advk_pcie_driver);
1282 
1283 MODULE_DESCRIPTION("Aardvark PCIe controller");
1284 MODULE_LICENSE("GPL v2");
1285