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_DEV_REV_REG					0x8
35 #define PCIE_CORE_PCIEXP_CAP					0xc0
36 #define PCIE_CORE_ERR_CAPCTL_REG				0x118
37 #define     PCIE_CORE_ERR_CAPCTL_ECRC_CHK_TX			BIT(5)
38 #define     PCIE_CORE_ERR_CAPCTL_ECRC_CHK_TX_EN			BIT(6)
39 #define     PCIE_CORE_ERR_CAPCTL_ECRC_CHCK			BIT(7)
40 #define     PCIE_CORE_ERR_CAPCTL_ECRC_CHCK_RCV			BIT(8)
41 #define     PCIE_CORE_INT_A_ASSERT_ENABLE			1
42 #define     PCIE_CORE_INT_B_ASSERT_ENABLE			2
43 #define     PCIE_CORE_INT_C_ASSERT_ENABLE			3
44 #define     PCIE_CORE_INT_D_ASSERT_ENABLE			4
45 /* PIO registers base address and register offsets */
46 #define PIO_BASE_ADDR				0x4000
47 #define PIO_CTRL				(PIO_BASE_ADDR + 0x0)
48 #define   PIO_CTRL_TYPE_MASK			GENMASK(3, 0)
49 #define   PIO_CTRL_ADDR_WIN_DISABLE		BIT(24)
50 #define PIO_STAT				(PIO_BASE_ADDR + 0x4)
51 #define   PIO_COMPLETION_STATUS_SHIFT		7
52 #define   PIO_COMPLETION_STATUS_MASK		GENMASK(9, 7)
53 #define   PIO_COMPLETION_STATUS_OK		0
54 #define   PIO_COMPLETION_STATUS_UR		1
55 #define   PIO_COMPLETION_STATUS_CRS		2
56 #define   PIO_COMPLETION_STATUS_CA		4
57 #define   PIO_NON_POSTED_REQ			BIT(10)
58 #define   PIO_ERR_STATUS			BIT(11)
59 #define PIO_ADDR_LS				(PIO_BASE_ADDR + 0x8)
60 #define PIO_ADDR_MS				(PIO_BASE_ADDR + 0xc)
61 #define PIO_WR_DATA				(PIO_BASE_ADDR + 0x10)
62 #define PIO_WR_DATA_STRB			(PIO_BASE_ADDR + 0x14)
63 #define PIO_RD_DATA				(PIO_BASE_ADDR + 0x18)
64 #define PIO_START				(PIO_BASE_ADDR + 0x1c)
65 #define PIO_ISR					(PIO_BASE_ADDR + 0x20)
66 #define PIO_ISRM				(PIO_BASE_ADDR + 0x24)
67 
68 /* Aardvark Control registers */
69 #define CONTROL_BASE_ADDR			0x4800
70 #define PCIE_CORE_CTRL0_REG			(CONTROL_BASE_ADDR + 0x0)
71 #define     PCIE_GEN_SEL_MSK			0x3
72 #define     PCIE_GEN_SEL_SHIFT			0x0
73 #define     SPEED_GEN_1				0
74 #define     SPEED_GEN_2				1
75 #define     SPEED_GEN_3				2
76 #define     IS_RC_MSK				1
77 #define     IS_RC_SHIFT				2
78 #define     LANE_CNT_MSK			0x18
79 #define     LANE_CNT_SHIFT			0x3
80 #define     LANE_COUNT_1			(0 << LANE_CNT_SHIFT)
81 #define     LANE_COUNT_2			(1 << LANE_CNT_SHIFT)
82 #define     LANE_COUNT_4			(2 << LANE_CNT_SHIFT)
83 #define     LANE_COUNT_8			(3 << LANE_CNT_SHIFT)
84 #define     LINK_TRAINING_EN			BIT(6)
85 #define     LEGACY_INTA				BIT(28)
86 #define     LEGACY_INTB				BIT(29)
87 #define     LEGACY_INTC				BIT(30)
88 #define     LEGACY_INTD				BIT(31)
89 #define PCIE_CORE_CTRL1_REG			(CONTROL_BASE_ADDR + 0x4)
90 #define     HOT_RESET_GEN			BIT(0)
91 #define PCIE_CORE_CTRL2_REG			(CONTROL_BASE_ADDR + 0x8)
92 #define     PCIE_CORE_CTRL2_RESERVED		0x7
93 #define     PCIE_CORE_CTRL2_TD_ENABLE		BIT(4)
94 #define     PCIE_CORE_CTRL2_STRICT_ORDER_ENABLE	BIT(5)
95 #define     PCIE_CORE_CTRL2_OB_WIN_ENABLE	BIT(6)
96 #define     PCIE_CORE_CTRL2_MSI_ENABLE		BIT(10)
97 #define PCIE_CORE_REF_CLK_REG			(CONTROL_BASE_ADDR + 0x14)
98 #define     PCIE_CORE_REF_CLK_TX_ENABLE		BIT(1)
99 #define     PCIE_CORE_REF_CLK_RX_ENABLE		BIT(2)
100 #define PCIE_MSG_LOG_REG			(CONTROL_BASE_ADDR + 0x30)
101 #define PCIE_ISR0_REG				(CONTROL_BASE_ADDR + 0x40)
102 #define PCIE_MSG_PM_PME_MASK			BIT(7)
103 #define PCIE_ISR0_MASK_REG			(CONTROL_BASE_ADDR + 0x44)
104 #define     PCIE_ISR0_MSI_INT_PENDING		BIT(24)
105 #define     PCIE_ISR0_INTX_ASSERT(val)		BIT(16 + (val))
106 #define     PCIE_ISR0_INTX_DEASSERT(val)	BIT(20 + (val))
107 #define     PCIE_ISR0_ALL_MASK			GENMASK(31, 0)
108 #define PCIE_ISR1_REG				(CONTROL_BASE_ADDR + 0x48)
109 #define PCIE_ISR1_MASK_REG			(CONTROL_BASE_ADDR + 0x4C)
110 #define     PCIE_ISR1_POWER_STATE_CHANGE	BIT(4)
111 #define     PCIE_ISR1_FLUSH			BIT(5)
112 #define     PCIE_ISR1_INTX_ASSERT(val)		BIT(8 + (val))
113 #define     PCIE_ISR1_ALL_MASK			GENMASK(31, 0)
114 #define PCIE_MSI_ADDR_LOW_REG			(CONTROL_BASE_ADDR + 0x50)
115 #define PCIE_MSI_ADDR_HIGH_REG			(CONTROL_BASE_ADDR + 0x54)
116 #define PCIE_MSI_STATUS_REG			(CONTROL_BASE_ADDR + 0x58)
117 #define PCIE_MSI_MASK_REG			(CONTROL_BASE_ADDR + 0x5C)
118 #define PCIE_MSI_PAYLOAD_REG			(CONTROL_BASE_ADDR + 0x9C)
119 #define     PCIE_MSI_DATA_MASK			GENMASK(15, 0)
120 
121 /* PCIe window configuration */
122 #define OB_WIN_BASE_ADDR			0x4c00
123 #define OB_WIN_BLOCK_SIZE			0x20
124 #define OB_WIN_COUNT				8
125 #define OB_WIN_REG_ADDR(win, offset)		(OB_WIN_BASE_ADDR + \
126 						 OB_WIN_BLOCK_SIZE * (win) + \
127 						 (offset))
128 #define OB_WIN_MATCH_LS(win)			OB_WIN_REG_ADDR(win, 0x00)
129 #define     OB_WIN_ENABLE			BIT(0)
130 #define OB_WIN_MATCH_MS(win)			OB_WIN_REG_ADDR(win, 0x04)
131 #define OB_WIN_REMAP_LS(win)			OB_WIN_REG_ADDR(win, 0x08)
132 #define OB_WIN_REMAP_MS(win)			OB_WIN_REG_ADDR(win, 0x0c)
133 #define OB_WIN_MASK_LS(win)			OB_WIN_REG_ADDR(win, 0x10)
134 #define OB_WIN_MASK_MS(win)			OB_WIN_REG_ADDR(win, 0x14)
135 #define OB_WIN_ACTIONS(win)			OB_WIN_REG_ADDR(win, 0x18)
136 #define OB_WIN_DEFAULT_ACTIONS			(OB_WIN_ACTIONS(OB_WIN_COUNT-1) + 0x4)
137 #define     OB_WIN_FUNC_NUM_MASK		GENMASK(31, 24)
138 #define     OB_WIN_FUNC_NUM_SHIFT		24
139 #define     OB_WIN_FUNC_NUM_ENABLE		BIT(23)
140 #define     OB_WIN_BUS_NUM_BITS_MASK		GENMASK(22, 20)
141 #define     OB_WIN_BUS_NUM_BITS_SHIFT		20
142 #define     OB_WIN_MSG_CODE_ENABLE		BIT(22)
143 #define     OB_WIN_MSG_CODE_MASK		GENMASK(21, 14)
144 #define     OB_WIN_MSG_CODE_SHIFT		14
145 #define     OB_WIN_MSG_PAYLOAD_LEN		BIT(12)
146 #define     OB_WIN_ATTR_ENABLE			BIT(11)
147 #define     OB_WIN_ATTR_TC_MASK			GENMASK(10, 8)
148 #define     OB_WIN_ATTR_TC_SHIFT		8
149 #define     OB_WIN_ATTR_RELAXED			BIT(7)
150 #define     OB_WIN_ATTR_NOSNOOP			BIT(6)
151 #define     OB_WIN_ATTR_POISON			BIT(5)
152 #define     OB_WIN_ATTR_IDO			BIT(4)
153 #define     OB_WIN_TYPE_MASK			GENMASK(3, 0)
154 #define     OB_WIN_TYPE_SHIFT			0
155 #define     OB_WIN_TYPE_MEM			0x0
156 #define     OB_WIN_TYPE_IO			0x4
157 #define     OB_WIN_TYPE_CONFIG_TYPE0		0x8
158 #define     OB_WIN_TYPE_CONFIG_TYPE1		0x9
159 #define     OB_WIN_TYPE_MSG			0xc
160 
161 /* LMI registers base address and register offsets */
162 #define LMI_BASE_ADDR				0x6000
163 #define CFG_REG					(LMI_BASE_ADDR + 0x0)
164 #define     LTSSM_SHIFT				24
165 #define     LTSSM_MASK				0x3f
166 #define     RC_BAR_CONFIG			0x300
167 
168 /* LTSSM values in CFG_REG */
169 enum {
170 	LTSSM_DETECT_QUIET			= 0x0,
171 	LTSSM_DETECT_ACTIVE			= 0x1,
172 	LTSSM_POLLING_ACTIVE			= 0x2,
173 	LTSSM_POLLING_COMPLIANCE		= 0x3,
174 	LTSSM_POLLING_CONFIGURATION		= 0x4,
175 	LTSSM_CONFIG_LINKWIDTH_START		= 0x5,
176 	LTSSM_CONFIG_LINKWIDTH_ACCEPT		= 0x6,
177 	LTSSM_CONFIG_LANENUM_ACCEPT		= 0x7,
178 	LTSSM_CONFIG_LANENUM_WAIT		= 0x8,
179 	LTSSM_CONFIG_COMPLETE			= 0x9,
180 	LTSSM_CONFIG_IDLE			= 0xa,
181 	LTSSM_RECOVERY_RCVR_LOCK		= 0xb,
182 	LTSSM_RECOVERY_SPEED			= 0xc,
183 	LTSSM_RECOVERY_RCVR_CFG			= 0xd,
184 	LTSSM_RECOVERY_IDLE			= 0xe,
185 	LTSSM_L0				= 0x10,
186 	LTSSM_RX_L0S_ENTRY			= 0x11,
187 	LTSSM_RX_L0S_IDLE			= 0x12,
188 	LTSSM_RX_L0S_FTS			= 0x13,
189 	LTSSM_TX_L0S_ENTRY			= 0x14,
190 	LTSSM_TX_L0S_IDLE			= 0x15,
191 	LTSSM_TX_L0S_FTS			= 0x16,
192 	LTSSM_L1_ENTRY				= 0x17,
193 	LTSSM_L1_IDLE				= 0x18,
194 	LTSSM_L2_IDLE				= 0x19,
195 	LTSSM_L2_TRANSMIT_WAKE			= 0x1a,
196 	LTSSM_DISABLED				= 0x20,
197 	LTSSM_LOOPBACK_ENTRY_MASTER		= 0x21,
198 	LTSSM_LOOPBACK_ACTIVE_MASTER		= 0x22,
199 	LTSSM_LOOPBACK_EXIT_MASTER		= 0x23,
200 	LTSSM_LOOPBACK_ENTRY_SLAVE		= 0x24,
201 	LTSSM_LOOPBACK_ACTIVE_SLAVE		= 0x25,
202 	LTSSM_LOOPBACK_EXIT_SLAVE		= 0x26,
203 	LTSSM_HOT_RESET				= 0x27,
204 	LTSSM_RECOVERY_EQUALIZATION_PHASE0	= 0x28,
205 	LTSSM_RECOVERY_EQUALIZATION_PHASE1	= 0x29,
206 	LTSSM_RECOVERY_EQUALIZATION_PHASE2	= 0x2a,
207 	LTSSM_RECOVERY_EQUALIZATION_PHASE3	= 0x2b,
208 };
209 
210 #define VENDOR_ID_REG				(LMI_BASE_ADDR + 0x44)
211 
212 /* PCIe core controller registers */
213 #define CTRL_CORE_BASE_ADDR			0x18000
214 #define CTRL_CONFIG_REG				(CTRL_CORE_BASE_ADDR + 0x0)
215 #define     CTRL_MODE_SHIFT			0x0
216 #define     CTRL_MODE_MASK			0x1
217 #define     PCIE_CORE_MODE_DIRECT		0x0
218 #define     PCIE_CORE_MODE_COMMAND		0x1
219 
220 /* PCIe Central Interrupts Registers */
221 #define CENTRAL_INT_BASE_ADDR			0x1b000
222 #define HOST_CTRL_INT_STATUS_REG		(CENTRAL_INT_BASE_ADDR + 0x0)
223 #define HOST_CTRL_INT_MASK_REG			(CENTRAL_INT_BASE_ADDR + 0x4)
224 #define     PCIE_IRQ_CMDQ_INT			BIT(0)
225 #define     PCIE_IRQ_MSI_STATUS_INT		BIT(1)
226 #define     PCIE_IRQ_CMD_SENT_DONE		BIT(3)
227 #define     PCIE_IRQ_DMA_INT			BIT(4)
228 #define     PCIE_IRQ_IB_DXFERDONE		BIT(5)
229 #define     PCIE_IRQ_OB_DXFERDONE		BIT(6)
230 #define     PCIE_IRQ_OB_RXFERDONE		BIT(7)
231 #define     PCIE_IRQ_COMPQ_INT			BIT(12)
232 #define     PCIE_IRQ_DIR_RD_DDR_DET		BIT(13)
233 #define     PCIE_IRQ_DIR_WR_DDR_DET		BIT(14)
234 #define     PCIE_IRQ_CORE_INT			BIT(16)
235 #define     PCIE_IRQ_CORE_INT_PIO		BIT(17)
236 #define     PCIE_IRQ_DPMU_INT			BIT(18)
237 #define     PCIE_IRQ_PCIE_MIS_INT		BIT(19)
238 #define     PCIE_IRQ_MSI_INT1_DET		BIT(20)
239 #define     PCIE_IRQ_MSI_INT2_DET		BIT(21)
240 #define     PCIE_IRQ_RC_DBELL_DET		BIT(22)
241 #define     PCIE_IRQ_EP_STATUS			BIT(23)
242 #define     PCIE_IRQ_ALL_MASK			GENMASK(31, 0)
243 #define     PCIE_IRQ_ENABLE_INTS_MASK		PCIE_IRQ_CORE_INT
244 
245 /* Transaction types */
246 #define PCIE_CONFIG_RD_TYPE0			0x8
247 #define PCIE_CONFIG_RD_TYPE1			0x9
248 #define PCIE_CONFIG_WR_TYPE0			0xa
249 #define PCIE_CONFIG_WR_TYPE1			0xb
250 
251 #define PIO_RETRY_CNT			750000 /* 1.5 s */
252 #define PIO_RETRY_DELAY			2 /* 2 us*/
253 
254 #define LINK_WAIT_MAX_RETRIES		10
255 #define LINK_WAIT_USLEEP_MIN		90000
256 #define LINK_WAIT_USLEEP_MAX		100000
257 #define RETRAIN_WAIT_MAX_RETRIES	10
258 #define RETRAIN_WAIT_USLEEP_US		2000
259 
260 #define MSI_IRQ_NUM			32
261 
262 #define CFG_RD_CRS_VAL			0xffff0001
263 
264 struct advk_pcie {
265 	struct platform_device *pdev;
266 	void __iomem *base;
267 	struct {
268 		phys_addr_t match;
269 		phys_addr_t remap;
270 		phys_addr_t mask;
271 		u32 actions;
272 	} wins[OB_WIN_COUNT];
273 	u8 wins_count;
274 	struct irq_domain *irq_domain;
275 	struct irq_chip irq_chip;
276 	raw_spinlock_t irq_lock;
277 	struct irq_domain *msi_domain;
278 	struct irq_domain *msi_inner_domain;
279 	struct irq_chip msi_bottom_irq_chip;
280 	struct irq_chip msi_irq_chip;
281 	struct msi_domain_info msi_domain_info;
282 	DECLARE_BITMAP(msi_used, MSI_IRQ_NUM);
283 	struct mutex msi_used_lock;
284 	u16 msi_msg;
285 	int link_gen;
286 	struct pci_bridge_emul bridge;
287 	struct gpio_desc *reset_gpio;
288 	struct phy *phy;
289 };
290 
291 static inline void advk_writel(struct advk_pcie *pcie, u32 val, u64 reg)
292 {
293 	writel(val, pcie->base + reg);
294 }
295 
296 static inline u32 advk_readl(struct advk_pcie *pcie, u64 reg)
297 {
298 	return readl(pcie->base + reg);
299 }
300 
301 static u8 advk_pcie_ltssm_state(struct advk_pcie *pcie)
302 {
303 	u32 val;
304 	u8 ltssm_state;
305 
306 	val = advk_readl(pcie, CFG_REG);
307 	ltssm_state = (val >> LTSSM_SHIFT) & LTSSM_MASK;
308 	return ltssm_state;
309 }
310 
311 static inline bool advk_pcie_link_up(struct advk_pcie *pcie)
312 {
313 	/* check if LTSSM is in normal operation - some L* state */
314 	u8 ltssm_state = advk_pcie_ltssm_state(pcie);
315 	return ltssm_state >= LTSSM_L0 && ltssm_state < LTSSM_DISABLED;
316 }
317 
318 static inline bool advk_pcie_link_active(struct advk_pcie *pcie)
319 {
320 	/*
321 	 * According to PCIe Base specification 3.0, Table 4-14: Link
322 	 * Status Mapped to the LTSSM, and 4.2.6.3.6 Configuration.Idle
323 	 * is Link Up mapped to LTSSM Configuration.Idle, Recovery, L0,
324 	 * L0s, L1 and L2 states. And according to 3.2.1. Data Link
325 	 * Control and Management State Machine Rules is DL Up status
326 	 * reported in DL Active state.
327 	 */
328 	u8 ltssm_state = advk_pcie_ltssm_state(pcie);
329 	return ltssm_state >= LTSSM_CONFIG_IDLE && ltssm_state < LTSSM_DISABLED;
330 }
331 
332 static inline bool advk_pcie_link_training(struct advk_pcie *pcie)
333 {
334 	/*
335 	 * According to PCIe Base specification 3.0, Table 4-14: Link
336 	 * Status Mapped to the LTSSM is Link Training mapped to LTSSM
337 	 * Configuration and Recovery states.
338 	 */
339 	u8 ltssm_state = advk_pcie_ltssm_state(pcie);
340 	return ((ltssm_state >= LTSSM_CONFIG_LINKWIDTH_START &&
341 		 ltssm_state < LTSSM_L0) ||
342 		(ltssm_state >= LTSSM_RECOVERY_EQUALIZATION_PHASE0 &&
343 		 ltssm_state <= LTSSM_RECOVERY_EQUALIZATION_PHASE3));
344 }
345 
346 static int advk_pcie_wait_for_link(struct advk_pcie *pcie)
347 {
348 	int retries;
349 
350 	/* check if the link is up or not */
351 	for (retries = 0; retries < LINK_WAIT_MAX_RETRIES; retries++) {
352 		if (advk_pcie_link_up(pcie))
353 			return 0;
354 
355 		usleep_range(LINK_WAIT_USLEEP_MIN, LINK_WAIT_USLEEP_MAX);
356 	}
357 
358 	return -ETIMEDOUT;
359 }
360 
361 static void advk_pcie_wait_for_retrain(struct advk_pcie *pcie)
362 {
363 	size_t retries;
364 
365 	for (retries = 0; retries < RETRAIN_WAIT_MAX_RETRIES; ++retries) {
366 		if (advk_pcie_link_training(pcie))
367 			break;
368 		udelay(RETRAIN_WAIT_USLEEP_US);
369 	}
370 }
371 
372 static void advk_pcie_issue_perst(struct advk_pcie *pcie)
373 {
374 	if (!pcie->reset_gpio)
375 		return;
376 
377 	/* 10ms delay is needed for some cards */
378 	dev_info(&pcie->pdev->dev, "issuing PERST via reset GPIO for 10ms\n");
379 	gpiod_set_value_cansleep(pcie->reset_gpio, 1);
380 	usleep_range(10000, 11000);
381 	gpiod_set_value_cansleep(pcie->reset_gpio, 0);
382 }
383 
384 static void advk_pcie_train_link(struct advk_pcie *pcie)
385 {
386 	struct device *dev = &pcie->pdev->dev;
387 	u32 reg;
388 	int ret;
389 
390 	/*
391 	 * Setup PCIe rev / gen compliance based on device tree property
392 	 * 'max-link-speed' which also forces maximal link speed.
393 	 */
394 	reg = advk_readl(pcie, PCIE_CORE_CTRL0_REG);
395 	reg &= ~PCIE_GEN_SEL_MSK;
396 	if (pcie->link_gen == 3)
397 		reg |= SPEED_GEN_3;
398 	else if (pcie->link_gen == 2)
399 		reg |= SPEED_GEN_2;
400 	else
401 		reg |= SPEED_GEN_1;
402 	advk_writel(pcie, reg, PCIE_CORE_CTRL0_REG);
403 
404 	/*
405 	 * Set maximal link speed value also into PCIe Link Control 2 register.
406 	 * Armada 3700 Functional Specification says that default value is based
407 	 * on SPEED_GEN but tests showed that default value is always 8.0 GT/s.
408 	 */
409 	reg = advk_readl(pcie, PCIE_CORE_PCIEXP_CAP + PCI_EXP_LNKCTL2);
410 	reg &= ~PCI_EXP_LNKCTL2_TLS;
411 	if (pcie->link_gen == 3)
412 		reg |= PCI_EXP_LNKCTL2_TLS_8_0GT;
413 	else if (pcie->link_gen == 2)
414 		reg |= PCI_EXP_LNKCTL2_TLS_5_0GT;
415 	else
416 		reg |= PCI_EXP_LNKCTL2_TLS_2_5GT;
417 	advk_writel(pcie, reg, PCIE_CORE_PCIEXP_CAP + PCI_EXP_LNKCTL2);
418 
419 	/* Enable link training after selecting PCIe generation */
420 	reg = advk_readl(pcie, PCIE_CORE_CTRL0_REG);
421 	reg |= LINK_TRAINING_EN;
422 	advk_writel(pcie, reg, PCIE_CORE_CTRL0_REG);
423 
424 	/*
425 	 * Reset PCIe card via PERST# signal. Some cards are not detected
426 	 * during link training when they are in some non-initial state.
427 	 */
428 	advk_pcie_issue_perst(pcie);
429 
430 	/*
431 	 * PERST# signal could have been asserted by pinctrl subsystem before
432 	 * probe() callback has been called or issued explicitly by reset gpio
433 	 * function advk_pcie_issue_perst(), making the endpoint going into
434 	 * fundamental reset. As required by PCI Express spec (PCI Express
435 	 * Base Specification, REV. 4.0 PCI Express, February 19 2014, 6.6.1
436 	 * Conventional Reset) a delay for at least 100ms after such a reset
437 	 * before sending a Configuration Request to the device is needed.
438 	 * So wait until PCIe link is up. Function advk_pcie_wait_for_link()
439 	 * waits for link at least 900ms.
440 	 */
441 	ret = advk_pcie_wait_for_link(pcie);
442 	if (ret < 0)
443 		dev_err(dev, "link never came up\n");
444 	else
445 		dev_info(dev, "link up\n");
446 }
447 
448 /*
449  * Set PCIe address window register which could be used for memory
450  * mapping.
451  */
452 static void advk_pcie_set_ob_win(struct advk_pcie *pcie, u8 win_num,
453 				 phys_addr_t match, phys_addr_t remap,
454 				 phys_addr_t mask, u32 actions)
455 {
456 	advk_writel(pcie, OB_WIN_ENABLE |
457 			  lower_32_bits(match), OB_WIN_MATCH_LS(win_num));
458 	advk_writel(pcie, upper_32_bits(match), OB_WIN_MATCH_MS(win_num));
459 	advk_writel(pcie, lower_32_bits(remap), OB_WIN_REMAP_LS(win_num));
460 	advk_writel(pcie, upper_32_bits(remap), OB_WIN_REMAP_MS(win_num));
461 	advk_writel(pcie, lower_32_bits(mask), OB_WIN_MASK_LS(win_num));
462 	advk_writel(pcie, upper_32_bits(mask), OB_WIN_MASK_MS(win_num));
463 	advk_writel(pcie, actions, OB_WIN_ACTIONS(win_num));
464 }
465 
466 static void advk_pcie_disable_ob_win(struct advk_pcie *pcie, u8 win_num)
467 {
468 	advk_writel(pcie, 0, OB_WIN_MATCH_LS(win_num));
469 	advk_writel(pcie, 0, OB_WIN_MATCH_MS(win_num));
470 	advk_writel(pcie, 0, OB_WIN_REMAP_LS(win_num));
471 	advk_writel(pcie, 0, OB_WIN_REMAP_MS(win_num));
472 	advk_writel(pcie, 0, OB_WIN_MASK_LS(win_num));
473 	advk_writel(pcie, 0, OB_WIN_MASK_MS(win_num));
474 	advk_writel(pcie, 0, OB_WIN_ACTIONS(win_num));
475 }
476 
477 static void advk_pcie_setup_hw(struct advk_pcie *pcie)
478 {
479 	u32 reg;
480 	int i;
481 
482 	/*
483 	 * Configure PCIe Reference clock. Direction is from the PCIe
484 	 * controller to the endpoint card, so enable transmitting of
485 	 * Reference clock differential signal off-chip and disable
486 	 * receiving off-chip differential signal.
487 	 */
488 	reg = advk_readl(pcie, PCIE_CORE_REF_CLK_REG);
489 	reg |= PCIE_CORE_REF_CLK_TX_ENABLE;
490 	reg &= ~PCIE_CORE_REF_CLK_RX_ENABLE;
491 	advk_writel(pcie, reg, PCIE_CORE_REF_CLK_REG);
492 
493 	/* Set to Direct mode */
494 	reg = advk_readl(pcie, CTRL_CONFIG_REG);
495 	reg &= ~(CTRL_MODE_MASK << CTRL_MODE_SHIFT);
496 	reg |= ((PCIE_CORE_MODE_DIRECT & CTRL_MODE_MASK) << CTRL_MODE_SHIFT);
497 	advk_writel(pcie, reg, CTRL_CONFIG_REG);
498 
499 	/* Set PCI global control register to RC mode */
500 	reg = advk_readl(pcie, PCIE_CORE_CTRL0_REG);
501 	reg |= (IS_RC_MSK << IS_RC_SHIFT);
502 	advk_writel(pcie, reg, PCIE_CORE_CTRL0_REG);
503 
504 	/*
505 	 * Replace incorrect PCI vendor id value 0x1b4b by correct value 0x11ab.
506 	 * VENDOR_ID_REG contains vendor id in low 16 bits and subsystem vendor
507 	 * id in high 16 bits. Updating this register changes readback value of
508 	 * read-only vendor id bits in PCIE_CORE_DEV_ID_REG register. Workaround
509 	 * for erratum 4.1: "The value of device and vendor ID is incorrect".
510 	 */
511 	reg = (PCI_VENDOR_ID_MARVELL << 16) | PCI_VENDOR_ID_MARVELL;
512 	advk_writel(pcie, reg, VENDOR_ID_REG);
513 
514 	/*
515 	 * Change Class Code of PCI Bridge device to PCI Bridge (0x600400),
516 	 * because the default value is Mass storage controller (0x010400).
517 	 *
518 	 * Note that this Aardvark PCI Bridge does not have compliant Type 1
519 	 * Configuration Space and it even cannot be accessed via Aardvark's
520 	 * PCI config space access method. Something like config space is
521 	 * available in internal Aardvark registers starting at offset 0x0
522 	 * and is reported as Type 0. In range 0x10 - 0x34 it has totally
523 	 * different registers.
524 	 *
525 	 * Therefore driver uses emulation of PCI Bridge which emulates
526 	 * access to configuration space via internal Aardvark registers or
527 	 * emulated configuration buffer.
528 	 */
529 	reg = advk_readl(pcie, PCIE_CORE_DEV_REV_REG);
530 	reg &= ~0xffffff00;
531 	reg |= (PCI_CLASS_BRIDGE_PCI << 8) << 8;
532 	advk_writel(pcie, reg, PCIE_CORE_DEV_REV_REG);
533 
534 	/* Disable Root Bridge I/O space, memory space and bus mastering */
535 	reg = advk_readl(pcie, PCIE_CORE_CMD_STATUS_REG);
536 	reg &= ~(PCI_COMMAND_IO | PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER);
537 	advk_writel(pcie, reg, PCIE_CORE_CMD_STATUS_REG);
538 
539 	/* Set Advanced Error Capabilities and Control PF0 register */
540 	reg = PCIE_CORE_ERR_CAPCTL_ECRC_CHK_TX |
541 		PCIE_CORE_ERR_CAPCTL_ECRC_CHK_TX_EN |
542 		PCIE_CORE_ERR_CAPCTL_ECRC_CHCK |
543 		PCIE_CORE_ERR_CAPCTL_ECRC_CHCK_RCV;
544 	advk_writel(pcie, reg, PCIE_CORE_ERR_CAPCTL_REG);
545 
546 	/* Set PCIe Device Control register */
547 	reg = advk_readl(pcie, PCIE_CORE_PCIEXP_CAP + PCI_EXP_DEVCTL);
548 	reg &= ~PCI_EXP_DEVCTL_RELAX_EN;
549 	reg &= ~PCI_EXP_DEVCTL_NOSNOOP_EN;
550 	reg &= ~PCI_EXP_DEVCTL_PAYLOAD;
551 	reg &= ~PCI_EXP_DEVCTL_READRQ;
552 	reg |= PCI_EXP_DEVCTL_PAYLOAD_512B;
553 	reg |= PCI_EXP_DEVCTL_READRQ_512B;
554 	advk_writel(pcie, reg, PCIE_CORE_PCIEXP_CAP + PCI_EXP_DEVCTL);
555 
556 	/* Program PCIe Control 2 to disable strict ordering */
557 	reg = PCIE_CORE_CTRL2_RESERVED |
558 		PCIE_CORE_CTRL2_TD_ENABLE;
559 	advk_writel(pcie, reg, PCIE_CORE_CTRL2_REG);
560 
561 	/* Set lane X1 */
562 	reg = advk_readl(pcie, PCIE_CORE_CTRL0_REG);
563 	reg &= ~LANE_CNT_MSK;
564 	reg |= LANE_COUNT_1;
565 	advk_writel(pcie, reg, PCIE_CORE_CTRL0_REG);
566 
567 	/* Enable MSI */
568 	reg = advk_readl(pcie, PCIE_CORE_CTRL2_REG);
569 	reg |= PCIE_CORE_CTRL2_MSI_ENABLE;
570 	advk_writel(pcie, reg, PCIE_CORE_CTRL2_REG);
571 
572 	/* Clear all interrupts */
573 	advk_writel(pcie, PCIE_ISR0_ALL_MASK, PCIE_ISR0_REG);
574 	advk_writel(pcie, PCIE_ISR1_ALL_MASK, PCIE_ISR1_REG);
575 	advk_writel(pcie, PCIE_IRQ_ALL_MASK, HOST_CTRL_INT_STATUS_REG);
576 
577 	/* Disable All ISR0/1 Sources */
578 	reg = PCIE_ISR0_ALL_MASK;
579 	reg &= ~PCIE_ISR0_MSI_INT_PENDING;
580 	advk_writel(pcie, reg, PCIE_ISR0_MASK_REG);
581 
582 	advk_writel(pcie, PCIE_ISR1_ALL_MASK, PCIE_ISR1_MASK_REG);
583 
584 	/* Unmask all MSIs */
585 	advk_writel(pcie, 0, PCIE_MSI_MASK_REG);
586 
587 	/* Enable summary interrupt for GIC SPI source */
588 	reg = PCIE_IRQ_ALL_MASK & (~PCIE_IRQ_ENABLE_INTS_MASK);
589 	advk_writel(pcie, reg, HOST_CTRL_INT_MASK_REG);
590 
591 	/*
592 	 * Enable AXI address window location generation:
593 	 * When it is enabled, the default outbound window
594 	 * configurations (Default User Field: 0xD0074CFC)
595 	 * are used to transparent address translation for
596 	 * the outbound transactions. Thus, PCIe address
597 	 * windows are not required for transparent memory
598 	 * access when default outbound window configuration
599 	 * is set for memory access.
600 	 */
601 	reg = advk_readl(pcie, PCIE_CORE_CTRL2_REG);
602 	reg |= PCIE_CORE_CTRL2_OB_WIN_ENABLE;
603 	advk_writel(pcie, reg, PCIE_CORE_CTRL2_REG);
604 
605 	/*
606 	 * Set memory access in Default User Field so it
607 	 * is not required to configure PCIe address for
608 	 * transparent memory access.
609 	 */
610 	advk_writel(pcie, OB_WIN_TYPE_MEM, OB_WIN_DEFAULT_ACTIONS);
611 
612 	/*
613 	 * Bypass the address window mapping for PIO:
614 	 * Since PIO access already contains all required
615 	 * info over AXI interface by PIO registers, the
616 	 * address window is not required.
617 	 */
618 	reg = advk_readl(pcie, PIO_CTRL);
619 	reg |= PIO_CTRL_ADDR_WIN_DISABLE;
620 	advk_writel(pcie, reg, PIO_CTRL);
621 
622 	/*
623 	 * Configure PCIe address windows for non-memory or
624 	 * non-transparent access as by default PCIe uses
625 	 * transparent memory access.
626 	 */
627 	for (i = 0; i < pcie->wins_count; i++)
628 		advk_pcie_set_ob_win(pcie, i,
629 				     pcie->wins[i].match, pcie->wins[i].remap,
630 				     pcie->wins[i].mask, pcie->wins[i].actions);
631 
632 	/* Disable remaining PCIe outbound windows */
633 	for (i = pcie->wins_count; i < OB_WIN_COUNT; i++)
634 		advk_pcie_disable_ob_win(pcie, i);
635 
636 	advk_pcie_train_link(pcie);
637 }
638 
639 static int advk_pcie_check_pio_status(struct advk_pcie *pcie, bool allow_crs, u32 *val)
640 {
641 	struct device *dev = &pcie->pdev->dev;
642 	u32 reg;
643 	unsigned int status;
644 	char *strcomp_status, *str_posted;
645 	int ret;
646 
647 	reg = advk_readl(pcie, PIO_STAT);
648 	status = (reg & PIO_COMPLETION_STATUS_MASK) >>
649 		PIO_COMPLETION_STATUS_SHIFT;
650 
651 	/*
652 	 * According to HW spec, the PIO status check sequence as below:
653 	 * 1) even if COMPLETION_STATUS(bit9:7) indicates successful,
654 	 *    it still needs to check Error Status(bit11), only when this bit
655 	 *    indicates no error happen, the operation is successful.
656 	 * 2) value Unsupported Request(1) of COMPLETION_STATUS(bit9:7) only
657 	 *    means a PIO write error, and for PIO read it is successful with
658 	 *    a read value of 0xFFFFFFFF.
659 	 * 3) value Completion Retry Status(CRS) of COMPLETION_STATUS(bit9:7)
660 	 *    only means a PIO write error, and for PIO read it is successful
661 	 *    with a read value of 0xFFFF0001.
662 	 * 4) value Completer Abort (CA) of COMPLETION_STATUS(bit9:7) means
663 	 *    error for both PIO read and PIO write operation.
664 	 * 5) other errors are indicated as 'unknown'.
665 	 */
666 	switch (status) {
667 	case PIO_COMPLETION_STATUS_OK:
668 		if (reg & PIO_ERR_STATUS) {
669 			strcomp_status = "COMP_ERR";
670 			ret = -EFAULT;
671 			break;
672 		}
673 		/* Get the read result */
674 		if (val)
675 			*val = advk_readl(pcie, PIO_RD_DATA);
676 		/* No error */
677 		strcomp_status = NULL;
678 		ret = 0;
679 		break;
680 	case PIO_COMPLETION_STATUS_UR:
681 		strcomp_status = "UR";
682 		ret = -EOPNOTSUPP;
683 		break;
684 	case PIO_COMPLETION_STATUS_CRS:
685 		if (allow_crs && val) {
686 			/* PCIe r4.0, sec 2.3.2, says:
687 			 * If CRS Software Visibility is enabled:
688 			 * For a Configuration Read Request that includes both
689 			 * bytes of the Vendor ID field of a device Function's
690 			 * Configuration Space Header, the Root Complex must
691 			 * complete the Request to the host by returning a
692 			 * read-data value of 0001h for the Vendor ID field and
693 			 * all '1's for any additional bytes included in the
694 			 * request.
695 			 *
696 			 * So CRS in this case is not an error status.
697 			 */
698 			*val = CFG_RD_CRS_VAL;
699 			strcomp_status = NULL;
700 			ret = 0;
701 			break;
702 		}
703 		/* PCIe r4.0, sec 2.3.2, says:
704 		 * If CRS Software Visibility is not enabled, the Root Complex
705 		 * must re-issue the Configuration Request as a new Request.
706 		 * If CRS Software Visibility is enabled: For a Configuration
707 		 * Write Request or for any other Configuration Read Request,
708 		 * the Root Complex must re-issue the Configuration Request as
709 		 * a new Request.
710 		 * A Root Complex implementation may choose to limit the number
711 		 * of Configuration Request/CRS Completion Status loops before
712 		 * determining that something is wrong with the target of the
713 		 * Request and taking appropriate action, e.g., complete the
714 		 * Request to the host as a failed transaction.
715 		 *
716 		 * So return -EAGAIN and caller (pci-aardvark.c driver) will
717 		 * re-issue request again up to the PIO_RETRY_CNT retries.
718 		 */
719 		strcomp_status = "CRS";
720 		ret = -EAGAIN;
721 		break;
722 	case PIO_COMPLETION_STATUS_CA:
723 		strcomp_status = "CA";
724 		ret = -ECANCELED;
725 		break;
726 	default:
727 		strcomp_status = "Unknown";
728 		ret = -EINVAL;
729 		break;
730 	}
731 
732 	if (!strcomp_status)
733 		return ret;
734 
735 	if (reg & PIO_NON_POSTED_REQ)
736 		str_posted = "Non-posted";
737 	else
738 		str_posted = "Posted";
739 
740 	dev_dbg(dev, "%s PIO Response Status: %s, %#x @ %#x\n",
741 		str_posted, strcomp_status, reg, advk_readl(pcie, PIO_ADDR_LS));
742 
743 	return ret;
744 }
745 
746 static int advk_pcie_wait_pio(struct advk_pcie *pcie)
747 {
748 	struct device *dev = &pcie->pdev->dev;
749 	int i;
750 
751 	for (i = 1; i <= PIO_RETRY_CNT; i++) {
752 		u32 start, isr;
753 
754 		start = advk_readl(pcie, PIO_START);
755 		isr = advk_readl(pcie, PIO_ISR);
756 		if (!start && isr)
757 			return i;
758 		udelay(PIO_RETRY_DELAY);
759 	}
760 
761 	dev_err(dev, "PIO read/write transfer time out\n");
762 	return -ETIMEDOUT;
763 }
764 
765 static pci_bridge_emul_read_status_t
766 advk_pci_bridge_emul_base_conf_read(struct pci_bridge_emul *bridge,
767 				    int reg, u32 *value)
768 {
769 	struct advk_pcie *pcie = bridge->data;
770 
771 	switch (reg) {
772 	case PCI_COMMAND:
773 		*value = advk_readl(pcie, PCIE_CORE_CMD_STATUS_REG);
774 		return PCI_BRIDGE_EMUL_HANDLED;
775 
776 	case PCI_INTERRUPT_LINE: {
777 		/*
778 		 * From the whole 32bit register we support reading from HW only
779 		 * one bit: PCI_BRIDGE_CTL_BUS_RESET.
780 		 * Other bits are retrieved only from emulated config buffer.
781 		 */
782 		__le32 *cfgspace = (__le32 *)&bridge->conf;
783 		u32 val = le32_to_cpu(cfgspace[PCI_INTERRUPT_LINE / 4]);
784 		if (advk_readl(pcie, PCIE_CORE_CTRL1_REG) & HOT_RESET_GEN)
785 			val |= PCI_BRIDGE_CTL_BUS_RESET << 16;
786 		else
787 			val &= ~(PCI_BRIDGE_CTL_BUS_RESET << 16);
788 		*value = val;
789 		return PCI_BRIDGE_EMUL_HANDLED;
790 	}
791 
792 	default:
793 		return PCI_BRIDGE_EMUL_NOT_HANDLED;
794 	}
795 }
796 
797 static void
798 advk_pci_bridge_emul_base_conf_write(struct pci_bridge_emul *bridge,
799 				     int reg, u32 old, u32 new, u32 mask)
800 {
801 	struct advk_pcie *pcie = bridge->data;
802 
803 	switch (reg) {
804 	case PCI_COMMAND:
805 		advk_writel(pcie, new, PCIE_CORE_CMD_STATUS_REG);
806 		break;
807 
808 	case PCI_INTERRUPT_LINE:
809 		if (mask & (PCI_BRIDGE_CTL_BUS_RESET << 16)) {
810 			u32 val = advk_readl(pcie, PCIE_CORE_CTRL1_REG);
811 			if (new & (PCI_BRIDGE_CTL_BUS_RESET << 16))
812 				val |= HOT_RESET_GEN;
813 			else
814 				val &= ~HOT_RESET_GEN;
815 			advk_writel(pcie, val, PCIE_CORE_CTRL1_REG);
816 		}
817 		break;
818 
819 	default:
820 		break;
821 	}
822 }
823 
824 static pci_bridge_emul_read_status_t
825 advk_pci_bridge_emul_pcie_conf_read(struct pci_bridge_emul *bridge,
826 				    int reg, u32 *value)
827 {
828 	struct advk_pcie *pcie = bridge->data;
829 
830 
831 	switch (reg) {
832 	case PCI_EXP_SLTCTL:
833 		*value = PCI_EXP_SLTSTA_PDS << 16;
834 		return PCI_BRIDGE_EMUL_HANDLED;
835 
836 	case PCI_EXP_RTCTL: {
837 		u32 val = advk_readl(pcie, PCIE_ISR0_MASK_REG);
838 		*value = (val & PCIE_MSG_PM_PME_MASK) ? 0 : PCI_EXP_RTCTL_PMEIE;
839 		*value |= le16_to_cpu(bridge->pcie_conf.rootctl) & PCI_EXP_RTCTL_CRSSVE;
840 		*value |= PCI_EXP_RTCAP_CRSVIS << 16;
841 		return PCI_BRIDGE_EMUL_HANDLED;
842 	}
843 
844 	case PCI_EXP_RTSTA: {
845 		u32 isr0 = advk_readl(pcie, PCIE_ISR0_REG);
846 		u32 msglog = advk_readl(pcie, PCIE_MSG_LOG_REG);
847 		*value = (isr0 & PCIE_MSG_PM_PME_MASK) << 16 | (msglog >> 16);
848 		return PCI_BRIDGE_EMUL_HANDLED;
849 	}
850 
851 	case PCI_EXP_LNKCAP: {
852 		u32 val = advk_readl(pcie, PCIE_CORE_PCIEXP_CAP + reg);
853 		/*
854 		 * PCI_EXP_LNKCAP_DLLLARC bit is hardwired in aardvark HW to 0.
855 		 * But support for PCI_EXP_LNKSTA_DLLLA is emulated via ltssm
856 		 * state so explicitly enable PCI_EXP_LNKCAP_DLLLARC flag.
857 		 */
858 		val |= PCI_EXP_LNKCAP_DLLLARC;
859 		*value = val;
860 		return PCI_BRIDGE_EMUL_HANDLED;
861 	}
862 
863 	case PCI_EXP_LNKCTL: {
864 		/* u32 contains both PCI_EXP_LNKCTL and PCI_EXP_LNKSTA */
865 		u32 val = advk_readl(pcie, PCIE_CORE_PCIEXP_CAP + reg) &
866 			~(PCI_EXP_LNKSTA_LT << 16);
867 		if (advk_pcie_link_training(pcie))
868 			val |= (PCI_EXP_LNKSTA_LT << 16);
869 		if (advk_pcie_link_active(pcie))
870 			val |= (PCI_EXP_LNKSTA_DLLLA << 16);
871 		*value = val;
872 		return PCI_BRIDGE_EMUL_HANDLED;
873 	}
874 
875 	case PCI_CAP_LIST_ID:
876 	case PCI_EXP_DEVCAP:
877 	case PCI_EXP_DEVCTL:
878 		*value = advk_readl(pcie, PCIE_CORE_PCIEXP_CAP + reg);
879 		return PCI_BRIDGE_EMUL_HANDLED;
880 	default:
881 		return PCI_BRIDGE_EMUL_NOT_HANDLED;
882 	}
883 
884 }
885 
886 static void
887 advk_pci_bridge_emul_pcie_conf_write(struct pci_bridge_emul *bridge,
888 				     int reg, u32 old, u32 new, u32 mask)
889 {
890 	struct advk_pcie *pcie = bridge->data;
891 
892 	switch (reg) {
893 	case PCI_EXP_DEVCTL:
894 		advk_writel(pcie, new, PCIE_CORE_PCIEXP_CAP + reg);
895 		break;
896 
897 	case PCI_EXP_LNKCTL:
898 		advk_writel(pcie, new, PCIE_CORE_PCIEXP_CAP + reg);
899 		if (new & PCI_EXP_LNKCTL_RL)
900 			advk_pcie_wait_for_retrain(pcie);
901 		break;
902 
903 	case PCI_EXP_RTCTL: {
904 		/* Only mask/unmask PME interrupt */
905 		u32 val = advk_readl(pcie, PCIE_ISR0_MASK_REG) &
906 			~PCIE_MSG_PM_PME_MASK;
907 		if ((new & PCI_EXP_RTCTL_PMEIE) == 0)
908 			val |= PCIE_MSG_PM_PME_MASK;
909 		advk_writel(pcie, val, PCIE_ISR0_MASK_REG);
910 		break;
911 	}
912 
913 	case PCI_EXP_RTSTA:
914 		new = (new & PCI_EXP_RTSTA_PME) >> 9;
915 		advk_writel(pcie, new, PCIE_ISR0_REG);
916 		break;
917 
918 	default:
919 		break;
920 	}
921 }
922 
923 static struct pci_bridge_emul_ops advk_pci_bridge_emul_ops = {
924 	.read_base = advk_pci_bridge_emul_base_conf_read,
925 	.write_base = advk_pci_bridge_emul_base_conf_write,
926 	.read_pcie = advk_pci_bridge_emul_pcie_conf_read,
927 	.write_pcie = advk_pci_bridge_emul_pcie_conf_write,
928 };
929 
930 /*
931  * Initialize the configuration space of the PCI-to-PCI bridge
932  * associated with the given PCIe interface.
933  */
934 static int advk_sw_pci_bridge_init(struct advk_pcie *pcie)
935 {
936 	struct pci_bridge_emul *bridge = &pcie->bridge;
937 
938 	bridge->conf.vendor =
939 		cpu_to_le16(advk_readl(pcie, PCIE_CORE_DEV_ID_REG) & 0xffff);
940 	bridge->conf.device =
941 		cpu_to_le16(advk_readl(pcie, PCIE_CORE_DEV_ID_REG) >> 16);
942 	bridge->conf.class_revision =
943 		cpu_to_le32(advk_readl(pcie, PCIE_CORE_DEV_REV_REG) & 0xff);
944 
945 	/* Support 32 bits I/O addressing */
946 	bridge->conf.iobase = PCI_IO_RANGE_TYPE_32;
947 	bridge->conf.iolimit = PCI_IO_RANGE_TYPE_32;
948 
949 	/* Support 64 bits memory pref */
950 	bridge->conf.pref_mem_base = cpu_to_le16(PCI_PREF_RANGE_TYPE_64);
951 	bridge->conf.pref_mem_limit = cpu_to_le16(PCI_PREF_RANGE_TYPE_64);
952 
953 	/* Support interrupt A for MSI feature */
954 	bridge->conf.intpin = PCIE_CORE_INT_A_ASSERT_ENABLE;
955 
956 	/* Indicates supports for Completion Retry Status */
957 	bridge->pcie_conf.rootcap = cpu_to_le16(PCI_EXP_RTCAP_CRSVIS);
958 
959 	bridge->has_pcie = true;
960 	bridge->data = pcie;
961 	bridge->ops = &advk_pci_bridge_emul_ops;
962 
963 	return pci_bridge_emul_init(bridge, 0);
964 }
965 
966 static bool advk_pcie_valid_device(struct advk_pcie *pcie, struct pci_bus *bus,
967 				  int devfn)
968 {
969 	if (pci_is_root_bus(bus) && PCI_SLOT(devfn) != 0)
970 		return false;
971 
972 	/*
973 	 * If the link goes down after we check for link-up, nothing bad
974 	 * happens but the config access times out.
975 	 */
976 	if (!pci_is_root_bus(bus) && !advk_pcie_link_up(pcie))
977 		return false;
978 
979 	return true;
980 }
981 
982 static bool advk_pcie_pio_is_running(struct advk_pcie *pcie)
983 {
984 	struct device *dev = &pcie->pdev->dev;
985 
986 	/*
987 	 * Trying to start a new PIO transfer when previous has not completed
988 	 * cause External Abort on CPU which results in kernel panic:
989 	 *
990 	 *     SError Interrupt on CPU0, code 0xbf000002 -- SError
991 	 *     Kernel panic - not syncing: Asynchronous SError Interrupt
992 	 *
993 	 * Functions advk_pcie_rd_conf() and advk_pcie_wr_conf() are protected
994 	 * by raw_spin_lock_irqsave() at pci_lock_config() level to prevent
995 	 * concurrent calls at the same time. But because PIO transfer may take
996 	 * about 1.5s when link is down or card is disconnected, it means that
997 	 * advk_pcie_wait_pio() does not always have to wait for completion.
998 	 *
999 	 * Some versions of ARM Trusted Firmware handles this External Abort at
1000 	 * EL3 level and mask it to prevent kernel panic. Relevant TF-A commit:
1001 	 * https://git.trustedfirmware.org/TF-A/trusted-firmware-a.git/commit/?id=3c7dcdac5c50
1002 	 */
1003 	if (advk_readl(pcie, PIO_START)) {
1004 		dev_err(dev, "Previous PIO read/write transfer is still running\n");
1005 		return true;
1006 	}
1007 
1008 	return false;
1009 }
1010 
1011 static int advk_pcie_rd_conf(struct pci_bus *bus, u32 devfn,
1012 			     int where, int size, u32 *val)
1013 {
1014 	struct advk_pcie *pcie = bus->sysdata;
1015 	int retry_count;
1016 	bool allow_crs;
1017 	u32 reg;
1018 	int ret;
1019 
1020 	if (!advk_pcie_valid_device(pcie, bus, devfn)) {
1021 		*val = 0xffffffff;
1022 		return PCIBIOS_DEVICE_NOT_FOUND;
1023 	}
1024 
1025 	if (pci_is_root_bus(bus))
1026 		return pci_bridge_emul_conf_read(&pcie->bridge, where,
1027 						 size, val);
1028 
1029 	/*
1030 	 * Completion Retry Status is possible to return only when reading all
1031 	 * 4 bytes from PCI_VENDOR_ID and PCI_DEVICE_ID registers at once and
1032 	 * CRSSVE flag on Root Bridge is enabled.
1033 	 */
1034 	allow_crs = (where == PCI_VENDOR_ID) && (size == 4) &&
1035 		    (le16_to_cpu(pcie->bridge.pcie_conf.rootctl) &
1036 		     PCI_EXP_RTCTL_CRSSVE);
1037 
1038 	if (advk_pcie_pio_is_running(pcie))
1039 		goto try_crs;
1040 
1041 	/* Program the control register */
1042 	reg = advk_readl(pcie, PIO_CTRL);
1043 	reg &= ~PIO_CTRL_TYPE_MASK;
1044 	if (pci_is_root_bus(bus->parent))
1045 		reg |= PCIE_CONFIG_RD_TYPE0;
1046 	else
1047 		reg |= PCIE_CONFIG_RD_TYPE1;
1048 	advk_writel(pcie, reg, PIO_CTRL);
1049 
1050 	/* Program the address registers */
1051 	reg = ALIGN_DOWN(PCIE_ECAM_OFFSET(bus->number, devfn, where), 4);
1052 	advk_writel(pcie, reg, PIO_ADDR_LS);
1053 	advk_writel(pcie, 0, PIO_ADDR_MS);
1054 
1055 	/* Program the data strobe */
1056 	advk_writel(pcie, 0xf, PIO_WR_DATA_STRB);
1057 
1058 	retry_count = 0;
1059 	do {
1060 		/* Clear PIO DONE ISR and start the transfer */
1061 		advk_writel(pcie, 1, PIO_ISR);
1062 		advk_writel(pcie, 1, PIO_START);
1063 
1064 		ret = advk_pcie_wait_pio(pcie);
1065 		if (ret < 0)
1066 			goto try_crs;
1067 
1068 		retry_count += ret;
1069 
1070 		/* Check PIO status and get the read result */
1071 		ret = advk_pcie_check_pio_status(pcie, allow_crs, val);
1072 	} while (ret == -EAGAIN && retry_count < PIO_RETRY_CNT);
1073 
1074 	if (ret < 0)
1075 		goto fail;
1076 
1077 	if (size == 1)
1078 		*val = (*val >> (8 * (where & 3))) & 0xff;
1079 	else if (size == 2)
1080 		*val = (*val >> (8 * (where & 3))) & 0xffff;
1081 
1082 	return PCIBIOS_SUCCESSFUL;
1083 
1084 try_crs:
1085 	/*
1086 	 * If it is possible, return Completion Retry Status so that caller
1087 	 * tries to issue the request again instead of failing.
1088 	 */
1089 	if (allow_crs) {
1090 		*val = CFG_RD_CRS_VAL;
1091 		return PCIBIOS_SUCCESSFUL;
1092 	}
1093 
1094 fail:
1095 	*val = 0xffffffff;
1096 	return PCIBIOS_SET_FAILED;
1097 }
1098 
1099 static int advk_pcie_wr_conf(struct pci_bus *bus, u32 devfn,
1100 				int where, int size, u32 val)
1101 {
1102 	struct advk_pcie *pcie = bus->sysdata;
1103 	u32 reg;
1104 	u32 data_strobe = 0x0;
1105 	int retry_count;
1106 	int offset;
1107 	int ret;
1108 
1109 	if (!advk_pcie_valid_device(pcie, bus, devfn))
1110 		return PCIBIOS_DEVICE_NOT_FOUND;
1111 
1112 	if (pci_is_root_bus(bus))
1113 		return pci_bridge_emul_conf_write(&pcie->bridge, where,
1114 						  size, val);
1115 
1116 	if (where % size)
1117 		return PCIBIOS_SET_FAILED;
1118 
1119 	if (advk_pcie_pio_is_running(pcie))
1120 		return PCIBIOS_SET_FAILED;
1121 
1122 	/* Program the control register */
1123 	reg = advk_readl(pcie, PIO_CTRL);
1124 	reg &= ~PIO_CTRL_TYPE_MASK;
1125 	if (pci_is_root_bus(bus->parent))
1126 		reg |= PCIE_CONFIG_WR_TYPE0;
1127 	else
1128 		reg |= PCIE_CONFIG_WR_TYPE1;
1129 	advk_writel(pcie, reg, PIO_CTRL);
1130 
1131 	/* Program the address registers */
1132 	reg = ALIGN_DOWN(PCIE_ECAM_OFFSET(bus->number, devfn, where), 4);
1133 	advk_writel(pcie, reg, PIO_ADDR_LS);
1134 	advk_writel(pcie, 0, PIO_ADDR_MS);
1135 
1136 	/* Calculate the write strobe */
1137 	offset      = where & 0x3;
1138 	reg         = val << (8 * offset);
1139 	data_strobe = GENMASK(size - 1, 0) << offset;
1140 
1141 	/* Program the data register */
1142 	advk_writel(pcie, reg, PIO_WR_DATA);
1143 
1144 	/* Program the data strobe */
1145 	advk_writel(pcie, data_strobe, PIO_WR_DATA_STRB);
1146 
1147 	retry_count = 0;
1148 	do {
1149 		/* Clear PIO DONE ISR and start the transfer */
1150 		advk_writel(pcie, 1, PIO_ISR);
1151 		advk_writel(pcie, 1, PIO_START);
1152 
1153 		ret = advk_pcie_wait_pio(pcie);
1154 		if (ret < 0)
1155 			return PCIBIOS_SET_FAILED;
1156 
1157 		retry_count += ret;
1158 
1159 		ret = advk_pcie_check_pio_status(pcie, false, NULL);
1160 	} while (ret == -EAGAIN && retry_count < PIO_RETRY_CNT);
1161 
1162 	return ret < 0 ? PCIBIOS_SET_FAILED : PCIBIOS_SUCCESSFUL;
1163 }
1164 
1165 static struct pci_ops advk_pcie_ops = {
1166 	.read = advk_pcie_rd_conf,
1167 	.write = advk_pcie_wr_conf,
1168 };
1169 
1170 static void advk_msi_irq_compose_msi_msg(struct irq_data *data,
1171 					 struct msi_msg *msg)
1172 {
1173 	struct advk_pcie *pcie = irq_data_get_irq_chip_data(data);
1174 	phys_addr_t msi_msg = virt_to_phys(&pcie->msi_msg);
1175 
1176 	msg->address_lo = lower_32_bits(msi_msg);
1177 	msg->address_hi = upper_32_bits(msi_msg);
1178 	msg->data = data->irq;
1179 }
1180 
1181 static int advk_msi_set_affinity(struct irq_data *irq_data,
1182 				 const struct cpumask *mask, bool force)
1183 {
1184 	return -EINVAL;
1185 }
1186 
1187 static int advk_msi_irq_domain_alloc(struct irq_domain *domain,
1188 				     unsigned int virq,
1189 				     unsigned int nr_irqs, void *args)
1190 {
1191 	struct advk_pcie *pcie = domain->host_data;
1192 	int hwirq, i;
1193 
1194 	mutex_lock(&pcie->msi_used_lock);
1195 	hwirq = bitmap_find_next_zero_area(pcie->msi_used, MSI_IRQ_NUM,
1196 					   0, nr_irqs, 0);
1197 	if (hwirq >= MSI_IRQ_NUM) {
1198 		mutex_unlock(&pcie->msi_used_lock);
1199 		return -ENOSPC;
1200 	}
1201 
1202 	bitmap_set(pcie->msi_used, hwirq, nr_irqs);
1203 	mutex_unlock(&pcie->msi_used_lock);
1204 
1205 	for (i = 0; i < nr_irqs; i++)
1206 		irq_domain_set_info(domain, virq + i, hwirq + i,
1207 				    &pcie->msi_bottom_irq_chip,
1208 				    domain->host_data, handle_simple_irq,
1209 				    NULL, NULL);
1210 
1211 	return 0;
1212 }
1213 
1214 static void advk_msi_irq_domain_free(struct irq_domain *domain,
1215 				     unsigned int virq, unsigned int nr_irqs)
1216 {
1217 	struct irq_data *d = irq_domain_get_irq_data(domain, virq);
1218 	struct advk_pcie *pcie = domain->host_data;
1219 
1220 	mutex_lock(&pcie->msi_used_lock);
1221 	bitmap_clear(pcie->msi_used, d->hwirq, nr_irqs);
1222 	mutex_unlock(&pcie->msi_used_lock);
1223 }
1224 
1225 static const struct irq_domain_ops advk_msi_domain_ops = {
1226 	.alloc = advk_msi_irq_domain_alloc,
1227 	.free = advk_msi_irq_domain_free,
1228 };
1229 
1230 static void advk_pcie_irq_mask(struct irq_data *d)
1231 {
1232 	struct advk_pcie *pcie = d->domain->host_data;
1233 	irq_hw_number_t hwirq = irqd_to_hwirq(d);
1234 	unsigned long flags;
1235 	u32 mask;
1236 
1237 	raw_spin_lock_irqsave(&pcie->irq_lock, flags);
1238 	mask = advk_readl(pcie, PCIE_ISR1_MASK_REG);
1239 	mask |= PCIE_ISR1_INTX_ASSERT(hwirq);
1240 	advk_writel(pcie, mask, PCIE_ISR1_MASK_REG);
1241 	raw_spin_unlock_irqrestore(&pcie->irq_lock, flags);
1242 }
1243 
1244 static void advk_pcie_irq_unmask(struct irq_data *d)
1245 {
1246 	struct advk_pcie *pcie = d->domain->host_data;
1247 	irq_hw_number_t hwirq = irqd_to_hwirq(d);
1248 	unsigned long flags;
1249 	u32 mask;
1250 
1251 	raw_spin_lock_irqsave(&pcie->irq_lock, flags);
1252 	mask = advk_readl(pcie, PCIE_ISR1_MASK_REG);
1253 	mask &= ~PCIE_ISR1_INTX_ASSERT(hwirq);
1254 	advk_writel(pcie, mask, PCIE_ISR1_MASK_REG);
1255 	raw_spin_unlock_irqrestore(&pcie->irq_lock, flags);
1256 }
1257 
1258 static int advk_pcie_irq_map(struct irq_domain *h,
1259 			     unsigned int virq, irq_hw_number_t hwirq)
1260 {
1261 	struct advk_pcie *pcie = h->host_data;
1262 
1263 	advk_pcie_irq_mask(irq_get_irq_data(virq));
1264 	irq_set_status_flags(virq, IRQ_LEVEL);
1265 	irq_set_chip_and_handler(virq, &pcie->irq_chip,
1266 				 handle_level_irq);
1267 	irq_set_chip_data(virq, pcie);
1268 
1269 	return 0;
1270 }
1271 
1272 static const struct irq_domain_ops advk_pcie_irq_domain_ops = {
1273 	.map = advk_pcie_irq_map,
1274 	.xlate = irq_domain_xlate_onecell,
1275 };
1276 
1277 static int advk_pcie_init_msi_irq_domain(struct advk_pcie *pcie)
1278 {
1279 	struct device *dev = &pcie->pdev->dev;
1280 	struct device_node *node = dev->of_node;
1281 	struct irq_chip *bottom_ic, *msi_ic;
1282 	struct msi_domain_info *msi_di;
1283 	phys_addr_t msi_msg_phys;
1284 
1285 	mutex_init(&pcie->msi_used_lock);
1286 
1287 	bottom_ic = &pcie->msi_bottom_irq_chip;
1288 
1289 	bottom_ic->name = "MSI";
1290 	bottom_ic->irq_compose_msi_msg = advk_msi_irq_compose_msi_msg;
1291 	bottom_ic->irq_set_affinity = advk_msi_set_affinity;
1292 
1293 	msi_ic = &pcie->msi_irq_chip;
1294 	msi_ic->name = "advk-MSI";
1295 
1296 	msi_di = &pcie->msi_domain_info;
1297 	msi_di->flags = MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
1298 		MSI_FLAG_MULTI_PCI_MSI;
1299 	msi_di->chip = msi_ic;
1300 
1301 	msi_msg_phys = virt_to_phys(&pcie->msi_msg);
1302 
1303 	advk_writel(pcie, lower_32_bits(msi_msg_phys),
1304 		    PCIE_MSI_ADDR_LOW_REG);
1305 	advk_writel(pcie, upper_32_bits(msi_msg_phys),
1306 		    PCIE_MSI_ADDR_HIGH_REG);
1307 
1308 	pcie->msi_inner_domain =
1309 		irq_domain_add_linear(NULL, MSI_IRQ_NUM,
1310 				      &advk_msi_domain_ops, pcie);
1311 	if (!pcie->msi_inner_domain)
1312 		return -ENOMEM;
1313 
1314 	pcie->msi_domain =
1315 		pci_msi_create_irq_domain(of_node_to_fwnode(node),
1316 					  msi_di, pcie->msi_inner_domain);
1317 	if (!pcie->msi_domain) {
1318 		irq_domain_remove(pcie->msi_inner_domain);
1319 		return -ENOMEM;
1320 	}
1321 
1322 	return 0;
1323 }
1324 
1325 static void advk_pcie_remove_msi_irq_domain(struct advk_pcie *pcie)
1326 {
1327 	irq_domain_remove(pcie->msi_domain);
1328 	irq_domain_remove(pcie->msi_inner_domain);
1329 }
1330 
1331 static int advk_pcie_init_irq_domain(struct advk_pcie *pcie)
1332 {
1333 	struct device *dev = &pcie->pdev->dev;
1334 	struct device_node *node = dev->of_node;
1335 	struct device_node *pcie_intc_node;
1336 	struct irq_chip *irq_chip;
1337 	int ret = 0;
1338 
1339 	raw_spin_lock_init(&pcie->irq_lock);
1340 
1341 	pcie_intc_node =  of_get_next_child(node, NULL);
1342 	if (!pcie_intc_node) {
1343 		dev_err(dev, "No PCIe Intc node found\n");
1344 		return -ENODEV;
1345 	}
1346 
1347 	irq_chip = &pcie->irq_chip;
1348 
1349 	irq_chip->name = devm_kasprintf(dev, GFP_KERNEL, "%s-irq",
1350 					dev_name(dev));
1351 	if (!irq_chip->name) {
1352 		ret = -ENOMEM;
1353 		goto out_put_node;
1354 	}
1355 
1356 	irq_chip->irq_mask = advk_pcie_irq_mask;
1357 	irq_chip->irq_mask_ack = advk_pcie_irq_mask;
1358 	irq_chip->irq_unmask = advk_pcie_irq_unmask;
1359 
1360 	pcie->irq_domain =
1361 		irq_domain_add_linear(pcie_intc_node, PCI_NUM_INTX,
1362 				      &advk_pcie_irq_domain_ops, pcie);
1363 	if (!pcie->irq_domain) {
1364 		dev_err(dev, "Failed to get a INTx IRQ domain\n");
1365 		ret = -ENOMEM;
1366 		goto out_put_node;
1367 	}
1368 
1369 out_put_node:
1370 	of_node_put(pcie_intc_node);
1371 	return ret;
1372 }
1373 
1374 static void advk_pcie_remove_irq_domain(struct advk_pcie *pcie)
1375 {
1376 	irq_domain_remove(pcie->irq_domain);
1377 }
1378 
1379 static void advk_pcie_handle_msi(struct advk_pcie *pcie)
1380 {
1381 	u32 msi_val, msi_mask, msi_status, msi_idx;
1382 	u16 msi_data;
1383 
1384 	msi_mask = advk_readl(pcie, PCIE_MSI_MASK_REG);
1385 	msi_val = advk_readl(pcie, PCIE_MSI_STATUS_REG);
1386 	msi_status = msi_val & ~msi_mask;
1387 
1388 	for (msi_idx = 0; msi_idx < MSI_IRQ_NUM; msi_idx++) {
1389 		if (!(BIT(msi_idx) & msi_status))
1390 			continue;
1391 
1392 		/*
1393 		 * msi_idx contains bits [4:0] of the msi_data and msi_data
1394 		 * contains 16bit MSI interrupt number
1395 		 */
1396 		advk_writel(pcie, BIT(msi_idx), PCIE_MSI_STATUS_REG);
1397 		msi_data = advk_readl(pcie, PCIE_MSI_PAYLOAD_REG) & PCIE_MSI_DATA_MASK;
1398 		generic_handle_irq(msi_data);
1399 	}
1400 
1401 	advk_writel(pcie, PCIE_ISR0_MSI_INT_PENDING,
1402 		    PCIE_ISR0_REG);
1403 }
1404 
1405 static void advk_pcie_handle_int(struct advk_pcie *pcie)
1406 {
1407 	u32 isr0_val, isr0_mask, isr0_status;
1408 	u32 isr1_val, isr1_mask, isr1_status;
1409 	int i;
1410 
1411 	isr0_val = advk_readl(pcie, PCIE_ISR0_REG);
1412 	isr0_mask = advk_readl(pcie, PCIE_ISR0_MASK_REG);
1413 	isr0_status = isr0_val & ((~isr0_mask) & PCIE_ISR0_ALL_MASK);
1414 
1415 	isr1_val = advk_readl(pcie, PCIE_ISR1_REG);
1416 	isr1_mask = advk_readl(pcie, PCIE_ISR1_MASK_REG);
1417 	isr1_status = isr1_val & ((~isr1_mask) & PCIE_ISR1_ALL_MASK);
1418 
1419 	/* Process MSI interrupts */
1420 	if (isr0_status & PCIE_ISR0_MSI_INT_PENDING)
1421 		advk_pcie_handle_msi(pcie);
1422 
1423 	/* Process legacy interrupts */
1424 	for (i = 0; i < PCI_NUM_INTX; i++) {
1425 		if (!(isr1_status & PCIE_ISR1_INTX_ASSERT(i)))
1426 			continue;
1427 
1428 		advk_writel(pcie, PCIE_ISR1_INTX_ASSERT(i),
1429 			    PCIE_ISR1_REG);
1430 
1431 		generic_handle_domain_irq(pcie->irq_domain, i);
1432 	}
1433 }
1434 
1435 static irqreturn_t advk_pcie_irq_handler(int irq, void *arg)
1436 {
1437 	struct advk_pcie *pcie = arg;
1438 	u32 status;
1439 
1440 	status = advk_readl(pcie, HOST_CTRL_INT_STATUS_REG);
1441 	if (!(status & PCIE_IRQ_CORE_INT))
1442 		return IRQ_NONE;
1443 
1444 	advk_pcie_handle_int(pcie);
1445 
1446 	/* Clear interrupt */
1447 	advk_writel(pcie, PCIE_IRQ_CORE_INT, HOST_CTRL_INT_STATUS_REG);
1448 
1449 	return IRQ_HANDLED;
1450 }
1451 
1452 static void __maybe_unused advk_pcie_disable_phy(struct advk_pcie *pcie)
1453 {
1454 	phy_power_off(pcie->phy);
1455 	phy_exit(pcie->phy);
1456 }
1457 
1458 static int advk_pcie_enable_phy(struct advk_pcie *pcie)
1459 {
1460 	int ret;
1461 
1462 	if (!pcie->phy)
1463 		return 0;
1464 
1465 	ret = phy_init(pcie->phy);
1466 	if (ret)
1467 		return ret;
1468 
1469 	ret = phy_set_mode(pcie->phy, PHY_MODE_PCIE);
1470 	if (ret) {
1471 		phy_exit(pcie->phy);
1472 		return ret;
1473 	}
1474 
1475 	ret = phy_power_on(pcie->phy);
1476 	if (ret == -EOPNOTSUPP) {
1477 		dev_warn(&pcie->pdev->dev, "PHY unsupported by firmware\n");
1478 	} else if (ret) {
1479 		phy_exit(pcie->phy);
1480 		return ret;
1481 	}
1482 
1483 	return 0;
1484 }
1485 
1486 static int advk_pcie_setup_phy(struct advk_pcie *pcie)
1487 {
1488 	struct device *dev = &pcie->pdev->dev;
1489 	struct device_node *node = dev->of_node;
1490 	int ret = 0;
1491 
1492 	pcie->phy = devm_of_phy_get(dev, node, NULL);
1493 	if (IS_ERR(pcie->phy) && (PTR_ERR(pcie->phy) == -EPROBE_DEFER))
1494 		return PTR_ERR(pcie->phy);
1495 
1496 	/* Old bindings miss the PHY handle */
1497 	if (IS_ERR(pcie->phy)) {
1498 		dev_warn(dev, "PHY unavailable (%ld)\n", PTR_ERR(pcie->phy));
1499 		pcie->phy = NULL;
1500 		return 0;
1501 	}
1502 
1503 	ret = advk_pcie_enable_phy(pcie);
1504 	if (ret)
1505 		dev_err(dev, "Failed to initialize PHY (%d)\n", ret);
1506 
1507 	return ret;
1508 }
1509 
1510 static int advk_pcie_probe(struct platform_device *pdev)
1511 {
1512 	struct device *dev = &pdev->dev;
1513 	struct advk_pcie *pcie;
1514 	struct pci_host_bridge *bridge;
1515 	struct resource_entry *entry;
1516 	int ret, irq;
1517 
1518 	bridge = devm_pci_alloc_host_bridge(dev, sizeof(struct advk_pcie));
1519 	if (!bridge)
1520 		return -ENOMEM;
1521 
1522 	pcie = pci_host_bridge_priv(bridge);
1523 	pcie->pdev = pdev;
1524 	platform_set_drvdata(pdev, pcie);
1525 
1526 	resource_list_for_each_entry(entry, &bridge->windows) {
1527 		resource_size_t start = entry->res->start;
1528 		resource_size_t size = resource_size(entry->res);
1529 		unsigned long type = resource_type(entry->res);
1530 		u64 win_size;
1531 
1532 		/*
1533 		 * Aardvark hardware allows to configure also PCIe window
1534 		 * for config type 0 and type 1 mapping, but driver uses
1535 		 * only PIO for issuing configuration transfers which does
1536 		 * not use PCIe window configuration.
1537 		 */
1538 		if (type != IORESOURCE_MEM && type != IORESOURCE_MEM_64 &&
1539 		    type != IORESOURCE_IO)
1540 			continue;
1541 
1542 		/*
1543 		 * Skip transparent memory resources. Default outbound access
1544 		 * configuration is set to transparent memory access so it
1545 		 * does not need window configuration.
1546 		 */
1547 		if ((type == IORESOURCE_MEM || type == IORESOURCE_MEM_64) &&
1548 		    entry->offset == 0)
1549 			continue;
1550 
1551 		/*
1552 		 * The n-th PCIe window is configured by tuple (match, remap, mask)
1553 		 * and an access to address A uses this window if A matches the
1554 		 * match with given mask.
1555 		 * So every PCIe window size must be a power of two and every start
1556 		 * address must be aligned to window size. Minimal size is 64 KiB
1557 		 * because lower 16 bits of mask must be zero. Remapped address
1558 		 * may have set only bits from the mask.
1559 		 */
1560 		while (pcie->wins_count < OB_WIN_COUNT && size > 0) {
1561 			/* Calculate the largest aligned window size */
1562 			win_size = (1ULL << (fls64(size)-1)) |
1563 				   (start ? (1ULL << __ffs64(start)) : 0);
1564 			win_size = 1ULL << __ffs64(win_size);
1565 			if (win_size < 0x10000)
1566 				break;
1567 
1568 			dev_dbg(dev,
1569 				"Configuring PCIe window %d: [0x%llx-0x%llx] as %lu\n",
1570 				pcie->wins_count, (unsigned long long)start,
1571 				(unsigned long long)start + win_size, type);
1572 
1573 			if (type == IORESOURCE_IO) {
1574 				pcie->wins[pcie->wins_count].actions = OB_WIN_TYPE_IO;
1575 				pcie->wins[pcie->wins_count].match = pci_pio_to_address(start);
1576 			} else {
1577 				pcie->wins[pcie->wins_count].actions = OB_WIN_TYPE_MEM;
1578 				pcie->wins[pcie->wins_count].match = start;
1579 			}
1580 			pcie->wins[pcie->wins_count].remap = start - entry->offset;
1581 			pcie->wins[pcie->wins_count].mask = ~(win_size - 1);
1582 
1583 			if (pcie->wins[pcie->wins_count].remap & (win_size - 1))
1584 				break;
1585 
1586 			start += win_size;
1587 			size -= win_size;
1588 			pcie->wins_count++;
1589 		}
1590 
1591 		if (size > 0) {
1592 			dev_err(&pcie->pdev->dev,
1593 				"Invalid PCIe region [0x%llx-0x%llx]\n",
1594 				(unsigned long long)entry->res->start,
1595 				(unsigned long long)entry->res->end + 1);
1596 			return -EINVAL;
1597 		}
1598 	}
1599 
1600 	pcie->base = devm_platform_ioremap_resource(pdev, 0);
1601 	if (IS_ERR(pcie->base))
1602 		return PTR_ERR(pcie->base);
1603 
1604 	irq = platform_get_irq(pdev, 0);
1605 	if (irq < 0)
1606 		return irq;
1607 
1608 	ret = devm_request_irq(dev, irq, advk_pcie_irq_handler,
1609 			       IRQF_SHARED | IRQF_NO_THREAD, "advk-pcie",
1610 			       pcie);
1611 	if (ret) {
1612 		dev_err(dev, "Failed to register interrupt\n");
1613 		return ret;
1614 	}
1615 
1616 	pcie->reset_gpio = devm_gpiod_get_from_of_node(dev, dev->of_node,
1617 						       "reset-gpios", 0,
1618 						       GPIOD_OUT_LOW,
1619 						       "pcie1-reset");
1620 	ret = PTR_ERR_OR_ZERO(pcie->reset_gpio);
1621 	if (ret) {
1622 		if (ret == -ENOENT) {
1623 			pcie->reset_gpio = NULL;
1624 		} else {
1625 			if (ret != -EPROBE_DEFER)
1626 				dev_err(dev, "Failed to get reset-gpio: %i\n",
1627 					ret);
1628 			return ret;
1629 		}
1630 	}
1631 
1632 	ret = of_pci_get_max_link_speed(dev->of_node);
1633 	if (ret <= 0 || ret > 3)
1634 		pcie->link_gen = 3;
1635 	else
1636 		pcie->link_gen = ret;
1637 
1638 	ret = advk_pcie_setup_phy(pcie);
1639 	if (ret)
1640 		return ret;
1641 
1642 	advk_pcie_setup_hw(pcie);
1643 
1644 	ret = advk_sw_pci_bridge_init(pcie);
1645 	if (ret) {
1646 		dev_err(dev, "Failed to register emulated root PCI bridge\n");
1647 		return ret;
1648 	}
1649 
1650 	ret = advk_pcie_init_irq_domain(pcie);
1651 	if (ret) {
1652 		dev_err(dev, "Failed to initialize irq\n");
1653 		return ret;
1654 	}
1655 
1656 	ret = advk_pcie_init_msi_irq_domain(pcie);
1657 	if (ret) {
1658 		dev_err(dev, "Failed to initialize irq\n");
1659 		advk_pcie_remove_irq_domain(pcie);
1660 		return ret;
1661 	}
1662 
1663 	bridge->sysdata = pcie;
1664 	bridge->ops = &advk_pcie_ops;
1665 
1666 	ret = pci_host_probe(bridge);
1667 	if (ret < 0) {
1668 		advk_pcie_remove_msi_irq_domain(pcie);
1669 		advk_pcie_remove_irq_domain(pcie);
1670 		return ret;
1671 	}
1672 
1673 	return 0;
1674 }
1675 
1676 static int advk_pcie_remove(struct platform_device *pdev)
1677 {
1678 	struct advk_pcie *pcie = platform_get_drvdata(pdev);
1679 	struct pci_host_bridge *bridge = pci_host_bridge_from_priv(pcie);
1680 	int i;
1681 
1682 	pci_lock_rescan_remove();
1683 	pci_stop_root_bus(bridge->bus);
1684 	pci_remove_root_bus(bridge->bus);
1685 	pci_unlock_rescan_remove();
1686 
1687 	advk_pcie_remove_msi_irq_domain(pcie);
1688 	advk_pcie_remove_irq_domain(pcie);
1689 
1690 	/* Disable outbound address windows mapping */
1691 	for (i = 0; i < OB_WIN_COUNT; i++)
1692 		advk_pcie_disable_ob_win(pcie, i);
1693 
1694 	return 0;
1695 }
1696 
1697 static const struct of_device_id advk_pcie_of_match_table[] = {
1698 	{ .compatible = "marvell,armada-3700-pcie", },
1699 	{},
1700 };
1701 MODULE_DEVICE_TABLE(of, advk_pcie_of_match_table);
1702 
1703 static struct platform_driver advk_pcie_driver = {
1704 	.driver = {
1705 		.name = "advk-pcie",
1706 		.of_match_table = advk_pcie_of_match_table,
1707 	},
1708 	.probe = advk_pcie_probe,
1709 	.remove = advk_pcie_remove,
1710 };
1711 module_platform_driver(advk_pcie_driver);
1712 
1713 MODULE_DESCRIPTION("Aardvark PCIe controller");
1714 MODULE_LICENSE("GPL v2");
1715