xref: /linux/drivers/pci/controller/pci-aardvark.c (revision 6bba1de54cebcded567563311710f9b3111e2652)
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/bitfield.h>
12 #include <linux/delay.h>
13 #include <linux/gpio/consumer.h>
14 #include <linux/interrupt.h>
15 #include <linux/irq.h>
16 #include <linux/irqchip/irq-msi-lib.h>
17 #include <linux/irqdomain.h>
18 #include <linux/kernel.h>
19 #include <linux/module.h>
20 #include <linux/pci.h>
21 #include <linux/pci-ecam.h>
22 #include <linux/init.h>
23 #include <linux/phy/phy.h>
24 #include <linux/platform_device.h>
25 #include <linux/msi.h>
26 #include <linux/of_address.h>
27 #include <linux/of_pci.h>
28 
29 #include "pci-host-common.h"
30 #include "../pci.h"
31 #include "../pci-bridge-emul.h"
32 
33 /* PCIe core registers */
34 #define PCIE_CORE_DEV_ID_REG					0x0
35 #define PCIE_CORE_CMD_STATUS_REG				0x4
36 #define PCIE_CORE_DEV_REV_REG					0x8
37 #define PCIE_CORE_SSDEV_ID_REG					0x2c
38 #define PCIE_CORE_PCIEXP_CAP					0xc0
39 #define PCIE_CORE_PCIERR_CAP					0x100
40 #define PCIE_CORE_ERR_CAPCTL_REG				0x118
41 #define     PCIE_CORE_ERR_CAPCTL_ECRC_CHK_TX			BIT(5)
42 #define     PCIE_CORE_ERR_CAPCTL_ECRC_CHK_TX_EN			BIT(6)
43 #define     PCIE_CORE_ERR_CAPCTL_ECRC_CHCK			BIT(7)
44 #define     PCIE_CORE_ERR_CAPCTL_ECRC_CHCK_RCV			BIT(8)
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_RRS		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_CORR_ERR			BIT(11)
106 #define     PCIE_ISR0_NFAT_ERR			BIT(12)
107 #define     PCIE_ISR0_FAT_ERR			BIT(13)
108 #define     PCIE_ISR0_ERR_MASK			GENMASK(13, 11)
109 #define     PCIE_ISR0_INTX_ASSERT(val)		BIT(16 + (val))
110 #define     PCIE_ISR0_INTX_DEASSERT(val)	BIT(20 + (val))
111 #define     PCIE_ISR0_ALL_MASK			GENMASK(31, 0)
112 #define PCIE_ISR1_REG				(CONTROL_BASE_ADDR + 0x48)
113 #define PCIE_ISR1_MASK_REG			(CONTROL_BASE_ADDR + 0x4C)
114 #define     PCIE_ISR1_POWER_STATE_CHANGE	BIT(4)
115 #define     PCIE_ISR1_FLUSH			BIT(5)
116 #define     PCIE_ISR1_INTX_ASSERT(val)		BIT(8 + (val))
117 #define     PCIE_ISR1_ALL_MASK			GENMASK(31, 0)
118 #define PCIE_MSI_ADDR_LOW_REG			(CONTROL_BASE_ADDR + 0x50)
119 #define PCIE_MSI_ADDR_HIGH_REG			(CONTROL_BASE_ADDR + 0x54)
120 #define PCIE_MSI_STATUS_REG			(CONTROL_BASE_ADDR + 0x58)
121 #define PCIE_MSI_MASK_REG			(CONTROL_BASE_ADDR + 0x5C)
122 #define     PCIE_MSI_ALL_MASK			GENMASK(31, 0)
123 #define PCIE_MSI_PAYLOAD_REG			(CONTROL_BASE_ADDR + 0x9C)
124 #define     PCIE_MSI_DATA_MASK			GENMASK(15, 0)
125 
126 /* PCIe window configuration */
127 #define OB_WIN_BASE_ADDR			0x4c00
128 #define OB_WIN_BLOCK_SIZE			0x20
129 #define OB_WIN_COUNT				8
130 #define OB_WIN_REG_ADDR(win, offset)		(OB_WIN_BASE_ADDR + \
131 						 OB_WIN_BLOCK_SIZE * (win) + \
132 						 (offset))
133 #define OB_WIN_MATCH_LS(win)			OB_WIN_REG_ADDR(win, 0x00)
134 #define     OB_WIN_ENABLE			BIT(0)
135 #define OB_WIN_MATCH_MS(win)			OB_WIN_REG_ADDR(win, 0x04)
136 #define OB_WIN_REMAP_LS(win)			OB_WIN_REG_ADDR(win, 0x08)
137 #define OB_WIN_REMAP_MS(win)			OB_WIN_REG_ADDR(win, 0x0c)
138 #define OB_WIN_MASK_LS(win)			OB_WIN_REG_ADDR(win, 0x10)
139 #define OB_WIN_MASK_MS(win)			OB_WIN_REG_ADDR(win, 0x14)
140 #define OB_WIN_ACTIONS(win)			OB_WIN_REG_ADDR(win, 0x18)
141 #define OB_WIN_DEFAULT_ACTIONS			(OB_WIN_ACTIONS(OB_WIN_COUNT-1) + 0x4)
142 #define     OB_WIN_FUNC_NUM_MASK		GENMASK(31, 24)
143 #define     OB_WIN_FUNC_NUM_SHIFT		24
144 #define     OB_WIN_FUNC_NUM_ENABLE		BIT(23)
145 #define     OB_WIN_BUS_NUM_BITS_MASK		GENMASK(22, 20)
146 #define     OB_WIN_BUS_NUM_BITS_SHIFT		20
147 #define     OB_WIN_MSG_CODE_ENABLE		BIT(22)
148 #define     OB_WIN_MSG_CODE_MASK		GENMASK(21, 14)
149 #define     OB_WIN_MSG_CODE_SHIFT		14
150 #define     OB_WIN_MSG_PAYLOAD_LEN		BIT(12)
151 #define     OB_WIN_ATTR_ENABLE			BIT(11)
152 #define     OB_WIN_ATTR_TC_MASK			GENMASK(10, 8)
153 #define     OB_WIN_ATTR_TC_SHIFT		8
154 #define     OB_WIN_ATTR_RELAXED			BIT(7)
155 #define     OB_WIN_ATTR_NOSNOOP			BIT(6)
156 #define     OB_WIN_ATTR_POISON			BIT(5)
157 #define     OB_WIN_ATTR_IDO			BIT(4)
158 #define     OB_WIN_TYPE_MASK			GENMASK(3, 0)
159 #define     OB_WIN_TYPE_SHIFT			0
160 #define     OB_WIN_TYPE_MEM			0x0
161 #define     OB_WIN_TYPE_IO			0x4
162 #define     OB_WIN_TYPE_CONFIG_TYPE0		0x8
163 #define     OB_WIN_TYPE_CONFIG_TYPE1		0x9
164 #define     OB_WIN_TYPE_MSG			0xc
165 
166 /* LMI registers base address and register offsets */
167 #define LMI_BASE_ADDR				0x6000
168 #define CFG_REG					(LMI_BASE_ADDR + 0x0)
169 #define     LTSSM_SHIFT				24
170 #define     LTSSM_MASK				0x3f
171 #define     RC_BAR_CONFIG			0x300
172 
173 /* LTSSM values in CFG_REG */
174 enum {
175 	LTSSM_DETECT_QUIET			= 0x0,
176 	LTSSM_DETECT_ACTIVE			= 0x1,
177 	LTSSM_POLLING_ACTIVE			= 0x2,
178 	LTSSM_POLLING_COMPLIANCE		= 0x3,
179 	LTSSM_POLLING_CONFIGURATION		= 0x4,
180 	LTSSM_CONFIG_LINKWIDTH_START		= 0x5,
181 	LTSSM_CONFIG_LINKWIDTH_ACCEPT		= 0x6,
182 	LTSSM_CONFIG_LANENUM_ACCEPT		= 0x7,
183 	LTSSM_CONFIG_LANENUM_WAIT		= 0x8,
184 	LTSSM_CONFIG_COMPLETE			= 0x9,
185 	LTSSM_CONFIG_IDLE			= 0xa,
186 	LTSSM_RECOVERY_RCVR_LOCK		= 0xb,
187 	LTSSM_RECOVERY_SPEED			= 0xc,
188 	LTSSM_RECOVERY_RCVR_CFG			= 0xd,
189 	LTSSM_RECOVERY_IDLE			= 0xe,
190 	LTSSM_L0				= 0x10,
191 	LTSSM_RX_L0S_ENTRY			= 0x11,
192 	LTSSM_RX_L0S_IDLE			= 0x12,
193 	LTSSM_RX_L0S_FTS			= 0x13,
194 	LTSSM_TX_L0S_ENTRY			= 0x14,
195 	LTSSM_TX_L0S_IDLE			= 0x15,
196 	LTSSM_TX_L0S_FTS			= 0x16,
197 	LTSSM_L1_ENTRY				= 0x17,
198 	LTSSM_L1_IDLE				= 0x18,
199 	LTSSM_L2_IDLE				= 0x19,
200 	LTSSM_L2_TRANSMIT_WAKE			= 0x1a,
201 	LTSSM_DISABLED				= 0x20,
202 	LTSSM_LOOPBACK_ENTRY_MASTER		= 0x21,
203 	LTSSM_LOOPBACK_ACTIVE_MASTER		= 0x22,
204 	LTSSM_LOOPBACK_EXIT_MASTER		= 0x23,
205 	LTSSM_LOOPBACK_ENTRY_SLAVE		= 0x24,
206 	LTSSM_LOOPBACK_ACTIVE_SLAVE		= 0x25,
207 	LTSSM_LOOPBACK_EXIT_SLAVE		= 0x26,
208 	LTSSM_HOT_RESET				= 0x27,
209 	LTSSM_RECOVERY_EQUALIZATION_PHASE0	= 0x28,
210 	LTSSM_RECOVERY_EQUALIZATION_PHASE1	= 0x29,
211 	LTSSM_RECOVERY_EQUALIZATION_PHASE2	= 0x2a,
212 	LTSSM_RECOVERY_EQUALIZATION_PHASE3	= 0x2b,
213 };
214 
215 #define VENDOR_ID_REG				(LMI_BASE_ADDR + 0x44)
216 
217 /* PCIe core controller registers */
218 #define CTRL_CORE_BASE_ADDR			0x18000
219 #define CTRL_CONFIG_REG				(CTRL_CORE_BASE_ADDR + 0x0)
220 #define     CTRL_MODE_SHIFT			0x0
221 #define     CTRL_MODE_MASK			0x1
222 #define     PCIE_CORE_MODE_DIRECT		0x0
223 #define     PCIE_CORE_MODE_COMMAND		0x1
224 
225 /* PCIe Central Interrupts Registers */
226 #define CENTRAL_INT_BASE_ADDR			0x1b000
227 #define HOST_CTRL_INT_STATUS_REG		(CENTRAL_INT_BASE_ADDR + 0x0)
228 #define HOST_CTRL_INT_MASK_REG			(CENTRAL_INT_BASE_ADDR + 0x4)
229 #define     PCIE_IRQ_CMDQ_INT			BIT(0)
230 #define     PCIE_IRQ_MSI_STATUS_INT		BIT(1)
231 #define     PCIE_IRQ_CMD_SENT_DONE		BIT(3)
232 #define     PCIE_IRQ_DMA_INT			BIT(4)
233 #define     PCIE_IRQ_IB_DXFERDONE		BIT(5)
234 #define     PCIE_IRQ_OB_DXFERDONE		BIT(6)
235 #define     PCIE_IRQ_OB_RXFERDONE		BIT(7)
236 #define     PCIE_IRQ_COMPQ_INT			BIT(12)
237 #define     PCIE_IRQ_DIR_RD_DDR_DET		BIT(13)
238 #define     PCIE_IRQ_DIR_WR_DDR_DET		BIT(14)
239 #define     PCIE_IRQ_CORE_INT			BIT(16)
240 #define     PCIE_IRQ_CORE_INT_PIO		BIT(17)
241 #define     PCIE_IRQ_DPMU_INT			BIT(18)
242 #define     PCIE_IRQ_PCIE_MIS_INT		BIT(19)
243 #define     PCIE_IRQ_MSI_INT1_DET		BIT(20)
244 #define     PCIE_IRQ_MSI_INT2_DET		BIT(21)
245 #define     PCIE_IRQ_RC_DBELL_DET		BIT(22)
246 #define     PCIE_IRQ_EP_STATUS			BIT(23)
247 #define     PCIE_IRQ_ALL_MASK			GENMASK(31, 0)
248 #define     PCIE_IRQ_ENABLE_INTS_MASK		PCIE_IRQ_CORE_INT
249 
250 /* Transaction types */
251 #define PCIE_CONFIG_RD_TYPE0			0x8
252 #define PCIE_CONFIG_RD_TYPE1			0x9
253 #define PCIE_CONFIG_WR_TYPE0			0xa
254 #define PCIE_CONFIG_WR_TYPE1			0xb
255 
256 #define PIO_RETRY_CNT			750000 /* 1.5 s */
257 #define PIO_RETRY_DELAY			2 /* 2 us*/
258 
259 #define LINK_WAIT_MAX_RETRIES		10
260 #define LINK_WAIT_USLEEP_MIN		90000
261 #define LINK_WAIT_USLEEP_MAX		100000
262 #define RETRAIN_WAIT_MAX_RETRIES	10
263 #define RETRAIN_WAIT_USLEEP_US		2000
264 
265 #define MSI_IRQ_NUM			32
266 
267 #define CFG_RD_RRS_VAL			0xffff0001
268 
269 struct advk_pcie {
270 	struct platform_device *pdev;
271 	void __iomem *base;
272 	struct {
273 		phys_addr_t match;
274 		phys_addr_t remap;
275 		phys_addr_t mask;
276 		u32 actions;
277 	} wins[OB_WIN_COUNT];
278 	u8 wins_count;
279 	struct irq_domain *rp_irq_domain;
280 	struct irq_domain *irq_domain;
281 	struct irq_chip irq_chip;
282 	raw_spinlock_t irq_lock;
283 	struct irq_domain *msi_inner_domain;
284 	raw_spinlock_t msi_irq_lock;
285 	DECLARE_BITMAP(msi_used, MSI_IRQ_NUM);
286 	struct mutex msi_used_lock;
287 	int link_gen;
288 	struct pci_bridge_emul bridge;
289 	struct gpio_desc *reset_gpio;
290 	struct phy *phy;
291 };
292 
293 static inline void advk_writel(struct advk_pcie *pcie, u32 val, u64 reg)
294 {
295 	writel(val, pcie->base + reg);
296 }
297 
298 static inline u32 advk_readl(struct advk_pcie *pcie, u64 reg)
299 {
300 	return readl(pcie->base + reg);
301 }
302 
303 static u8 advk_pcie_ltssm_state(struct advk_pcie *pcie)
304 {
305 	u32 val;
306 	u8 ltssm_state;
307 
308 	val = advk_readl(pcie, CFG_REG);
309 	ltssm_state = (val >> LTSSM_SHIFT) & LTSSM_MASK;
310 	return ltssm_state;
311 }
312 
313 static inline bool advk_pcie_link_up(struct advk_pcie *pcie)
314 {
315 	/* check if LTSSM is in normal operation - some L* state */
316 	u8 ltssm_state = advk_pcie_ltssm_state(pcie);
317 	return ltssm_state >= LTSSM_L0 && ltssm_state < LTSSM_DISABLED;
318 }
319 
320 static inline bool advk_pcie_link_active(struct advk_pcie *pcie)
321 {
322 	/*
323 	 * According to PCIe Base specification 3.0, Table 4-14: Link
324 	 * Status Mapped to the LTSSM, and 4.2.6.3.6 Configuration.Idle
325 	 * is Link Up mapped to LTSSM Configuration.Idle, Recovery, L0,
326 	 * L0s, L1 and L2 states. And according to 3.2.1. Data Link
327 	 * Control and Management State Machine Rules is DL Up status
328 	 * reported in DL Active state.
329 	 */
330 	u8 ltssm_state = advk_pcie_ltssm_state(pcie);
331 	return ltssm_state >= LTSSM_CONFIG_IDLE && ltssm_state < LTSSM_DISABLED;
332 }
333 
334 static inline bool advk_pcie_link_training(struct advk_pcie *pcie)
335 {
336 	/*
337 	 * According to PCIe Base specification 3.0, Table 4-14: Link
338 	 * Status Mapped to the LTSSM is Link Training mapped to LTSSM
339 	 * Configuration and Recovery states.
340 	 */
341 	u8 ltssm_state = advk_pcie_ltssm_state(pcie);
342 	return ((ltssm_state >= LTSSM_CONFIG_LINKWIDTH_START &&
343 		 ltssm_state < LTSSM_L0) ||
344 		(ltssm_state >= LTSSM_RECOVERY_EQUALIZATION_PHASE0 &&
345 		 ltssm_state <= LTSSM_RECOVERY_EQUALIZATION_PHASE3));
346 }
347 
348 static int advk_pcie_wait_for_link(struct advk_pcie *pcie)
349 {
350 	int retries;
351 
352 	/* check if the link is up or not */
353 	for (retries = 0; retries < LINK_WAIT_MAX_RETRIES; retries++) {
354 		if (advk_pcie_link_up(pcie)) {
355 			pci_host_common_link_train_delay(pcie->link_gen);
356 			return 0;
357 		}
358 
359 		usleep_range(LINK_WAIT_USLEEP_MIN, LINK_WAIT_USLEEP_MAX);
360 	}
361 
362 	return -ETIMEDOUT;
363 }
364 
365 static void advk_pcie_wait_for_retrain(struct advk_pcie *pcie)
366 {
367 	size_t retries;
368 
369 	for (retries = 0; retries < RETRAIN_WAIT_MAX_RETRIES; ++retries) {
370 		if (advk_pcie_link_training(pcie))
371 			break;
372 		udelay(RETRAIN_WAIT_USLEEP_US);
373 	}
374 }
375 
376 static void advk_pcie_issue_perst(struct advk_pcie *pcie)
377 {
378 	if (!pcie->reset_gpio)
379 		return;
380 
381 	/* 10ms delay is needed for some cards */
382 	dev_info(&pcie->pdev->dev, "issuing PERST via reset GPIO for 10ms\n");
383 	gpiod_set_value_cansleep(pcie->reset_gpio, 1);
384 	usleep_range(10000, 11000);
385 	gpiod_set_value_cansleep(pcie->reset_gpio, 0);
386 }
387 
388 static void advk_pcie_train_link(struct advk_pcie *pcie)
389 {
390 	struct device *dev = &pcie->pdev->dev;
391 	u32 reg;
392 	int ret;
393 
394 	/*
395 	 * Setup PCIe rev / gen compliance based on device tree property
396 	 * 'max-link-speed' which also forces maximal link speed.
397 	 */
398 	reg = advk_readl(pcie, PCIE_CORE_CTRL0_REG);
399 	reg &= ~PCIE_GEN_SEL_MSK;
400 	if (pcie->link_gen == 3)
401 		reg |= SPEED_GEN_3;
402 	else if (pcie->link_gen == 2)
403 		reg |= SPEED_GEN_2;
404 	else
405 		reg |= SPEED_GEN_1;
406 	advk_writel(pcie, reg, PCIE_CORE_CTRL0_REG);
407 
408 	/*
409 	 * Set maximal link speed value also into PCIe Link Control 2 register.
410 	 * Armada 3700 Functional Specification says that default value is based
411 	 * on SPEED_GEN but tests showed that default value is always 8.0 GT/s.
412 	 */
413 	reg = advk_readl(pcie, PCIE_CORE_PCIEXP_CAP + PCI_EXP_LNKCTL2);
414 	reg &= ~PCI_EXP_LNKCTL2_TLS;
415 	if (pcie->link_gen == 3)
416 		reg |= PCI_EXP_LNKCTL2_TLS_8_0GT;
417 	else if (pcie->link_gen == 2)
418 		reg |= PCI_EXP_LNKCTL2_TLS_5_0GT;
419 	else
420 		reg |= PCI_EXP_LNKCTL2_TLS_2_5GT;
421 	advk_writel(pcie, reg, PCIE_CORE_PCIEXP_CAP + PCI_EXP_LNKCTL2);
422 
423 	/* Enable link training after selecting PCIe generation */
424 	reg = advk_readl(pcie, PCIE_CORE_CTRL0_REG);
425 	reg |= LINK_TRAINING_EN;
426 	advk_writel(pcie, reg, PCIE_CORE_CTRL0_REG);
427 
428 	/*
429 	 * Reset PCIe card via PERST# signal. Some cards are not detected
430 	 * during link training when they are in some non-initial state.
431 	 */
432 	advk_pcie_issue_perst(pcie);
433 
434 	/*
435 	 * PERST# signal could have been asserted by pinctrl subsystem before
436 	 * probe() callback has been called or issued explicitly by reset gpio
437 	 * function advk_pcie_issue_perst(), making the endpoint going into
438 	 * fundamental reset. As required by PCI Express spec (PCI Express
439 	 * Base Specification, REV. 4.0 PCI Express, February 19 2014, 6.6.1
440 	 * Conventional Reset) a delay for at least 100ms after such a reset
441 	 * before sending a Configuration Request to the device is needed.
442 	 * So wait until PCIe link is up. Function advk_pcie_wait_for_link()
443 	 * waits for link at least 900ms.
444 	 */
445 	ret = advk_pcie_wait_for_link(pcie);
446 	if (ret < 0)
447 		dev_err(dev, "link never came up\n");
448 	else
449 		dev_info(dev, "link up\n");
450 }
451 
452 /*
453  * Set PCIe address window register which could be used for memory
454  * mapping.
455  */
456 static void advk_pcie_set_ob_win(struct advk_pcie *pcie, u8 win_num,
457 				 phys_addr_t match, phys_addr_t remap,
458 				 phys_addr_t mask, u32 actions)
459 {
460 	advk_writel(pcie, OB_WIN_ENABLE |
461 			  lower_32_bits(match), OB_WIN_MATCH_LS(win_num));
462 	advk_writel(pcie, upper_32_bits(match), OB_WIN_MATCH_MS(win_num));
463 	advk_writel(pcie, lower_32_bits(remap), OB_WIN_REMAP_LS(win_num));
464 	advk_writel(pcie, upper_32_bits(remap), OB_WIN_REMAP_MS(win_num));
465 	advk_writel(pcie, lower_32_bits(mask), OB_WIN_MASK_LS(win_num));
466 	advk_writel(pcie, upper_32_bits(mask), OB_WIN_MASK_MS(win_num));
467 	advk_writel(pcie, actions, OB_WIN_ACTIONS(win_num));
468 }
469 
470 static void advk_pcie_disable_ob_win(struct advk_pcie *pcie, u8 win_num)
471 {
472 	advk_writel(pcie, 0, OB_WIN_MATCH_LS(win_num));
473 	advk_writel(pcie, 0, OB_WIN_MATCH_MS(win_num));
474 	advk_writel(pcie, 0, OB_WIN_REMAP_LS(win_num));
475 	advk_writel(pcie, 0, OB_WIN_REMAP_MS(win_num));
476 	advk_writel(pcie, 0, OB_WIN_MASK_LS(win_num));
477 	advk_writel(pcie, 0, OB_WIN_MASK_MS(win_num));
478 	advk_writel(pcie, 0, OB_WIN_ACTIONS(win_num));
479 }
480 
481 static void advk_pcie_setup_hw(struct advk_pcie *pcie)
482 {
483 	phys_addr_t msi_addr;
484 	u32 reg;
485 	int i;
486 
487 	/*
488 	 * Configure PCIe Reference clock. Direction is from the PCIe
489 	 * controller to the endpoint card, so enable transmitting of
490 	 * Reference clock differential signal off-chip and disable
491 	 * receiving off-chip differential signal.
492 	 */
493 	reg = advk_readl(pcie, PCIE_CORE_REF_CLK_REG);
494 	reg |= PCIE_CORE_REF_CLK_TX_ENABLE;
495 	reg &= ~PCIE_CORE_REF_CLK_RX_ENABLE;
496 	advk_writel(pcie, reg, PCIE_CORE_REF_CLK_REG);
497 
498 	/* Set to Direct mode */
499 	reg = advk_readl(pcie, CTRL_CONFIG_REG);
500 	reg &= ~(CTRL_MODE_MASK << CTRL_MODE_SHIFT);
501 	reg |= ((PCIE_CORE_MODE_DIRECT & CTRL_MODE_MASK) << CTRL_MODE_SHIFT);
502 	advk_writel(pcie, reg, CTRL_CONFIG_REG);
503 
504 	/* Set PCI global control register to RC mode */
505 	reg = advk_readl(pcie, PCIE_CORE_CTRL0_REG);
506 	reg |= (IS_RC_MSK << IS_RC_SHIFT);
507 	advk_writel(pcie, reg, PCIE_CORE_CTRL0_REG);
508 
509 	/*
510 	 * Replace incorrect PCI vendor id value 0x1b4b by correct value 0x11ab.
511 	 * VENDOR_ID_REG contains vendor id in low 16 bits and subsystem vendor
512 	 * id in high 16 bits. Updating this register changes readback value of
513 	 * read-only vendor id bits in PCIE_CORE_DEV_ID_REG register. Workaround
514 	 * for erratum 4.1: "The value of device and vendor ID is incorrect".
515 	 */
516 	reg = (PCI_VENDOR_ID_MARVELL << 16) | PCI_VENDOR_ID_MARVELL;
517 	advk_writel(pcie, reg, VENDOR_ID_REG);
518 
519 	/*
520 	 * Change Class Code of PCI Bridge device to PCI Bridge (0x600400),
521 	 * because the default value is Mass storage controller (0x010400).
522 	 *
523 	 * Note that this Aardvark PCI Bridge does not have compliant Type 1
524 	 * Configuration Space and it even cannot be accessed via Aardvark's
525 	 * PCI config space access method. Something like config space is
526 	 * available in internal Aardvark registers starting at offset 0x0
527 	 * and is reported as Type 0. In range 0x10 - 0x34 it has totally
528 	 * different registers.
529 	 *
530 	 * Therefore driver uses emulation of PCI Bridge which emulates
531 	 * access to configuration space via internal Aardvark registers or
532 	 * emulated configuration buffer.
533 	 */
534 	reg = advk_readl(pcie, PCIE_CORE_DEV_REV_REG);
535 	reg &= ~0xffffff00;
536 	reg |= PCI_CLASS_BRIDGE_PCI_NORMAL << 8;
537 	advk_writel(pcie, reg, PCIE_CORE_DEV_REV_REG);
538 
539 	/* Disable Root Bridge I/O space, memory space and bus mastering */
540 	reg = advk_readl(pcie, PCIE_CORE_CMD_STATUS_REG);
541 	reg &= ~(PCI_COMMAND_IO | PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER);
542 	advk_writel(pcie, reg, PCIE_CORE_CMD_STATUS_REG);
543 
544 	/* Set Advanced Error Capabilities and Control PF0 register */
545 	reg = PCIE_CORE_ERR_CAPCTL_ECRC_CHK_TX |
546 		PCIE_CORE_ERR_CAPCTL_ECRC_CHK_TX_EN |
547 		PCIE_CORE_ERR_CAPCTL_ECRC_CHCK |
548 		PCIE_CORE_ERR_CAPCTL_ECRC_CHCK_RCV;
549 	advk_writel(pcie, reg, PCIE_CORE_ERR_CAPCTL_REG);
550 
551 	/* Set PCIe Device Control register */
552 	reg = advk_readl(pcie, PCIE_CORE_PCIEXP_CAP + PCI_EXP_DEVCTL);
553 	reg &= ~PCI_EXP_DEVCTL_RELAX_EN;
554 	reg &= ~PCI_EXP_DEVCTL_NOSNOOP_EN;
555 	reg &= ~PCI_EXP_DEVCTL_PAYLOAD;
556 	reg &= ~PCI_EXP_DEVCTL_READRQ;
557 	reg |= PCI_EXP_DEVCTL_PAYLOAD_512B;
558 	reg |= PCI_EXP_DEVCTL_READRQ_512B;
559 	advk_writel(pcie, reg, PCIE_CORE_PCIEXP_CAP + PCI_EXP_DEVCTL);
560 
561 	/* Program PCIe Control 2 to disable strict ordering */
562 	reg = PCIE_CORE_CTRL2_RESERVED |
563 		PCIE_CORE_CTRL2_TD_ENABLE;
564 	advk_writel(pcie, reg, PCIE_CORE_CTRL2_REG);
565 
566 	/* Set lane X1 */
567 	reg = advk_readl(pcie, PCIE_CORE_CTRL0_REG);
568 	reg &= ~LANE_CNT_MSK;
569 	reg |= LANE_COUNT_1;
570 	advk_writel(pcie, reg, PCIE_CORE_CTRL0_REG);
571 
572 	/* Set MSI address */
573 	msi_addr = virt_to_phys(pcie);
574 	advk_writel(pcie, lower_32_bits(msi_addr), PCIE_MSI_ADDR_LOW_REG);
575 	advk_writel(pcie, upper_32_bits(msi_addr), PCIE_MSI_ADDR_HIGH_REG);
576 
577 	/* Enable MSI */
578 	reg = advk_readl(pcie, PCIE_CORE_CTRL2_REG);
579 	reg |= PCIE_CORE_CTRL2_MSI_ENABLE;
580 	advk_writel(pcie, reg, PCIE_CORE_CTRL2_REG);
581 
582 	/* Clear all interrupts */
583 	advk_writel(pcie, PCIE_MSI_ALL_MASK, PCIE_MSI_STATUS_REG);
584 	advk_writel(pcie, PCIE_ISR0_ALL_MASK, PCIE_ISR0_REG);
585 	advk_writel(pcie, PCIE_ISR1_ALL_MASK, PCIE_ISR1_REG);
586 	advk_writel(pcie, PCIE_IRQ_ALL_MASK, HOST_CTRL_INT_STATUS_REG);
587 
588 	/* Disable All ISR0/1 and MSI Sources */
589 	advk_writel(pcie, PCIE_ISR0_ALL_MASK, PCIE_ISR0_MASK_REG);
590 	advk_writel(pcie, PCIE_ISR1_ALL_MASK, PCIE_ISR1_MASK_REG);
591 	advk_writel(pcie, PCIE_MSI_ALL_MASK, PCIE_MSI_MASK_REG);
592 
593 	/* Unmask summary MSI interrupt */
594 	reg = advk_readl(pcie, PCIE_ISR0_MASK_REG);
595 	reg &= ~PCIE_ISR0_MSI_INT_PENDING;
596 	advk_writel(pcie, reg, PCIE_ISR0_MASK_REG);
597 
598 	/* Unmask PME interrupt for processing of PME requester */
599 	reg = advk_readl(pcie, PCIE_ISR0_MASK_REG);
600 	reg &= ~PCIE_MSG_PM_PME_MASK;
601 	advk_writel(pcie, reg, PCIE_ISR0_MASK_REG);
602 
603 	/* Enable summary interrupt for GIC SPI source */
604 	reg = PCIE_IRQ_ALL_MASK & (~PCIE_IRQ_ENABLE_INTS_MASK);
605 	advk_writel(pcie, reg, HOST_CTRL_INT_MASK_REG);
606 
607 	/*
608 	 * Enable AXI address window location generation:
609 	 * When it is enabled, the default outbound window
610 	 * configurations (Default User Field: 0xD0074CFC)
611 	 * are used to transparent address translation for
612 	 * the outbound transactions. Thus, PCIe address
613 	 * windows are not required for transparent memory
614 	 * access when default outbound window configuration
615 	 * is set for memory access.
616 	 */
617 	reg = advk_readl(pcie, PCIE_CORE_CTRL2_REG);
618 	reg |= PCIE_CORE_CTRL2_OB_WIN_ENABLE;
619 	advk_writel(pcie, reg, PCIE_CORE_CTRL2_REG);
620 
621 	/*
622 	 * Set memory access in Default User Field so it
623 	 * is not required to configure PCIe address for
624 	 * transparent memory access.
625 	 */
626 	advk_writel(pcie, OB_WIN_TYPE_MEM, OB_WIN_DEFAULT_ACTIONS);
627 
628 	/*
629 	 * Bypass the address window mapping for PIO:
630 	 * Since PIO access already contains all required
631 	 * info over AXI interface by PIO registers, the
632 	 * address window is not required.
633 	 */
634 	reg = advk_readl(pcie, PIO_CTRL);
635 	reg |= PIO_CTRL_ADDR_WIN_DISABLE;
636 	advk_writel(pcie, reg, PIO_CTRL);
637 
638 	/*
639 	 * Configure PCIe address windows for non-memory or
640 	 * non-transparent access as by default PCIe uses
641 	 * transparent memory access.
642 	 */
643 	for (i = 0; i < pcie->wins_count; i++)
644 		advk_pcie_set_ob_win(pcie, i,
645 				     pcie->wins[i].match, pcie->wins[i].remap,
646 				     pcie->wins[i].mask, pcie->wins[i].actions);
647 
648 	/* Disable remaining PCIe outbound windows */
649 	for (i = pcie->wins_count; i < OB_WIN_COUNT; i++)
650 		advk_pcie_disable_ob_win(pcie, i);
651 
652 	advk_pcie_train_link(pcie);
653 }
654 
655 static int advk_pcie_check_pio_status(struct advk_pcie *pcie, bool allow_rrs, u32 *val)
656 {
657 	struct device *dev = &pcie->pdev->dev;
658 	u32 reg;
659 	unsigned int status;
660 	char *strcomp_status, *str_posted;
661 	int ret;
662 
663 	reg = advk_readl(pcie, PIO_STAT);
664 	status = (reg & PIO_COMPLETION_STATUS_MASK) >>
665 		PIO_COMPLETION_STATUS_SHIFT;
666 
667 	/*
668 	 * According to HW spec, the PIO status check sequence as below:
669 	 * 1) even if COMPLETION_STATUS(bit9:7) indicates successful,
670 	 *    it still needs to check Error Status(bit11), only when this bit
671 	 *    indicates no error happen, the operation is successful.
672 	 * 2) value Unsupported Request(1) of COMPLETION_STATUS(bit9:7) only
673 	 *    means a PIO write error, and for PIO read it is successful with
674 	 *    a read value of 0xFFFFFFFF.
675 	 * 3) value Config Request Retry Status(RRS) of COMPLETION_STATUS(bit9:7)
676 	 *    only means a PIO write error, and for PIO read it is successful
677 	 *    with a read value of 0xFFFF0001.
678 	 * 4) value Completer Abort (CA) of COMPLETION_STATUS(bit9:7) means
679 	 *    error for both PIO read and PIO write operation.
680 	 * 5) other errors are indicated as 'unknown'.
681 	 */
682 	switch (status) {
683 	case PIO_COMPLETION_STATUS_OK:
684 		if (reg & PIO_ERR_STATUS) {
685 			strcomp_status = "COMP_ERR";
686 			ret = -EFAULT;
687 			break;
688 		}
689 		/* Get the read result */
690 		if (val)
691 			*val = advk_readl(pcie, PIO_RD_DATA);
692 		/* No error */
693 		strcomp_status = NULL;
694 		ret = 0;
695 		break;
696 	case PIO_COMPLETION_STATUS_UR:
697 		strcomp_status = "UR";
698 		ret = -EOPNOTSUPP;
699 		break;
700 	case PIO_COMPLETION_STATUS_RRS:
701 		if (allow_rrs && val) {
702 			/* PCIe r6.0, sec 2.3.2, says:
703 			 * If Configuration RRS Software Visibility is enabled:
704 			 * For a Configuration Read Request that includes both
705 			 * bytes of the Vendor ID field of a device Function's
706 			 * Configuration Space Header, the Root Complex must
707 			 * complete the Request to the host by returning a
708 			 * read-data value of 0001h for the Vendor ID field and
709 			 * all '1's for any additional bytes included in the
710 			 * request.
711 			 *
712 			 * So RRS in this case is not an error status.
713 			 */
714 			*val = CFG_RD_RRS_VAL;
715 			strcomp_status = NULL;
716 			ret = 0;
717 			break;
718 		}
719 		/* PCIe r6.0, sec 2.3.2, says:
720 		 * If RRS Software Visibility is not enabled, the Root Complex
721 		 * must re-issue the Configuration Request as a new Request.
722 		 * If RRS Software Visibility is enabled: For a Configuration
723 		 * Write Request or for any other Configuration Read Request,
724 		 * the Root Complex must re-issue the Configuration Request as
725 		 * a new Request.
726 		 * A Root Complex implementation may choose to limit the number
727 		 * of Configuration Request/RRS Completion Status loops before
728 		 * determining that something is wrong with the target of the
729 		 * Request and taking appropriate action, e.g., complete the
730 		 * Request to the host as a failed transaction.
731 		 *
732 		 * So return -EAGAIN and caller (pci-aardvark.c driver) will
733 		 * re-issue request again up to the PIO_RETRY_CNT retries.
734 		 */
735 		strcomp_status = "RRS";
736 		ret = -EAGAIN;
737 		break;
738 	case PIO_COMPLETION_STATUS_CA:
739 		strcomp_status = "CA";
740 		ret = -ECANCELED;
741 		break;
742 	default:
743 		strcomp_status = "Unknown";
744 		ret = -EINVAL;
745 		break;
746 	}
747 
748 	if (!strcomp_status)
749 		return ret;
750 
751 	if (reg & PIO_NON_POSTED_REQ)
752 		str_posted = "Non-posted";
753 	else
754 		str_posted = "Posted";
755 
756 	dev_dbg(dev, "%s PIO Response Status: %s, %#x @ %#x\n",
757 		str_posted, strcomp_status, reg, advk_readl(pcie, PIO_ADDR_LS));
758 
759 	return ret;
760 }
761 
762 static int advk_pcie_wait_pio(struct advk_pcie *pcie)
763 {
764 	struct device *dev = &pcie->pdev->dev;
765 	int i;
766 
767 	for (i = 1; i <= PIO_RETRY_CNT; i++) {
768 		u32 start, isr;
769 
770 		start = advk_readl(pcie, PIO_START);
771 		isr = advk_readl(pcie, PIO_ISR);
772 		if (!start && isr)
773 			return i;
774 		udelay(PIO_RETRY_DELAY);
775 	}
776 
777 	dev_err(dev, "PIO read/write transfer time out\n");
778 	return -ETIMEDOUT;
779 }
780 
781 static pci_bridge_emul_read_status_t
782 advk_pci_bridge_emul_base_conf_read(struct pci_bridge_emul *bridge,
783 				    int reg, u32 *value)
784 {
785 	struct advk_pcie *pcie = bridge->data;
786 
787 	switch (reg) {
788 	case PCI_COMMAND:
789 		*value = advk_readl(pcie, PCIE_CORE_CMD_STATUS_REG);
790 		return PCI_BRIDGE_EMUL_HANDLED;
791 
792 	case PCI_INTERRUPT_LINE: {
793 		/*
794 		 * From the whole 32bit register we support reading from HW only
795 		 * two bits: PCI_BRIDGE_CTL_BUS_RESET and PCI_BRIDGE_CTL_SERR.
796 		 * Other bits are retrieved only from emulated config buffer.
797 		 */
798 		__le32 *cfgspace = (__le32 *)&bridge->conf;
799 		u32 val = le32_to_cpu(cfgspace[PCI_INTERRUPT_LINE / 4]);
800 		if (advk_readl(pcie, PCIE_ISR0_MASK_REG) & PCIE_ISR0_ERR_MASK)
801 			val &= ~(PCI_BRIDGE_CTL_SERR << 16);
802 		else
803 			val |= PCI_BRIDGE_CTL_SERR << 16;
804 		if (advk_readl(pcie, PCIE_CORE_CTRL1_REG) & HOT_RESET_GEN)
805 			val |= PCI_BRIDGE_CTL_BUS_RESET << 16;
806 		else
807 			val &= ~(PCI_BRIDGE_CTL_BUS_RESET << 16);
808 		*value = val;
809 		return PCI_BRIDGE_EMUL_HANDLED;
810 	}
811 
812 	default:
813 		return PCI_BRIDGE_EMUL_NOT_HANDLED;
814 	}
815 }
816 
817 static void
818 advk_pci_bridge_emul_base_conf_write(struct pci_bridge_emul *bridge,
819 				     int reg, u32 old, u32 new, u32 mask)
820 {
821 	struct advk_pcie *pcie = bridge->data;
822 
823 	switch (reg) {
824 	case PCI_COMMAND:
825 		advk_writel(pcie, new, PCIE_CORE_CMD_STATUS_REG);
826 		break;
827 
828 	case PCI_INTERRUPT_LINE:
829 		/*
830 		 * According to Figure 6-3: Pseudo Logic Diagram for Error
831 		 * Message Controls in PCIe base specification, SERR# Enable bit
832 		 * in Bridge Control register enable receiving of ERR_* messages
833 		 */
834 		if (mask & (PCI_BRIDGE_CTL_SERR << 16)) {
835 			u32 val = advk_readl(pcie, PCIE_ISR0_MASK_REG);
836 			if (new & (PCI_BRIDGE_CTL_SERR << 16))
837 				val &= ~PCIE_ISR0_ERR_MASK;
838 			else
839 				val |= PCIE_ISR0_ERR_MASK;
840 			advk_writel(pcie, val, PCIE_ISR0_MASK_REG);
841 		}
842 		if (mask & (PCI_BRIDGE_CTL_BUS_RESET << 16)) {
843 			u32 val = advk_readl(pcie, PCIE_CORE_CTRL1_REG);
844 			if (new & (PCI_BRIDGE_CTL_BUS_RESET << 16))
845 				val |= HOT_RESET_GEN;
846 			else
847 				val &= ~HOT_RESET_GEN;
848 			advk_writel(pcie, val, PCIE_CORE_CTRL1_REG);
849 		}
850 		break;
851 
852 	default:
853 		break;
854 	}
855 }
856 
857 static pci_bridge_emul_read_status_t
858 advk_pci_bridge_emul_pcie_conf_read(struct pci_bridge_emul *bridge,
859 				    int reg, u32 *value)
860 {
861 	struct advk_pcie *pcie = bridge->data;
862 
863 
864 	switch (reg) {
865 	/*
866 	 * PCI_EXP_SLTCAP, PCI_EXP_SLTCTL, PCI_EXP_RTCTL and PCI_EXP_RTSTA are
867 	 * also supported, but do not need to be handled here, because their
868 	 * values are stored in emulated config space buffer, and we read them
869 	 * from there when needed.
870 	 */
871 
872 	case PCI_EXP_LNKCAP: {
873 		u32 val = advk_readl(pcie, PCIE_CORE_PCIEXP_CAP + reg);
874 		/*
875 		 * PCI_EXP_LNKCAP_DLLLARC bit is hardwired in aardvark HW to 0.
876 		 * But support for PCI_EXP_LNKSTA_DLLLA is emulated via ltssm
877 		 * state so explicitly enable PCI_EXP_LNKCAP_DLLLARC flag.
878 		 */
879 		val |= PCI_EXP_LNKCAP_DLLLARC;
880 		*value = val;
881 		return PCI_BRIDGE_EMUL_HANDLED;
882 	}
883 
884 	case PCI_EXP_LNKCTL: {
885 		/* u32 contains both PCI_EXP_LNKCTL and PCI_EXP_LNKSTA */
886 		u32 val = advk_readl(pcie, PCIE_CORE_PCIEXP_CAP + reg) &
887 			~(PCI_EXP_LNKSTA_LT << 16);
888 		if (advk_pcie_link_training(pcie))
889 			val |= (PCI_EXP_LNKSTA_LT << 16);
890 		if (advk_pcie_link_active(pcie))
891 			val |= (PCI_EXP_LNKSTA_DLLLA << 16);
892 		*value = val;
893 		return PCI_BRIDGE_EMUL_HANDLED;
894 	}
895 
896 	case PCI_EXP_DEVCAP:
897 	case PCI_EXP_DEVCTL:
898 	case PCI_EXP_DEVCAP2:
899 	case PCI_EXP_DEVCTL2:
900 	case PCI_EXP_LNKCAP2:
901 	case PCI_EXP_LNKCTL2:
902 		*value = advk_readl(pcie, PCIE_CORE_PCIEXP_CAP + reg);
903 		return PCI_BRIDGE_EMUL_HANDLED;
904 
905 	default:
906 		return PCI_BRIDGE_EMUL_NOT_HANDLED;
907 	}
908 
909 }
910 
911 static void
912 advk_pci_bridge_emul_pcie_conf_write(struct pci_bridge_emul *bridge,
913 				     int reg, u32 old, u32 new, u32 mask)
914 {
915 	struct advk_pcie *pcie = bridge->data;
916 
917 	switch (reg) {
918 	case PCI_EXP_LNKCTL:
919 		advk_writel(pcie, new, PCIE_CORE_PCIEXP_CAP + reg);
920 		if (new & PCI_EXP_LNKCTL_RL)
921 			advk_pcie_wait_for_retrain(pcie);
922 		break;
923 
924 	case PCI_EXP_RTCTL: {
925 		u16 rootctl = le16_to_cpu(bridge->pcie_conf.rootctl);
926 		/* Only emulation of PMEIE and RRS_SVE bits is provided */
927 		rootctl &= PCI_EXP_RTCTL_PMEIE | PCI_EXP_RTCTL_RRS_SVE;
928 		bridge->pcie_conf.rootctl = cpu_to_le16(rootctl);
929 		break;
930 	}
931 
932 	/*
933 	 * PCI_EXP_RTSTA is also supported, but does not need to be handled
934 	 * here, because its value is stored in emulated config space buffer,
935 	 * and we write it there when needed.
936 	 */
937 
938 	case PCI_EXP_DEVCTL:
939 	case PCI_EXP_DEVCTL2:
940 	case PCI_EXP_LNKCTL2:
941 		advk_writel(pcie, new, PCIE_CORE_PCIEXP_CAP + reg);
942 		break;
943 
944 	default:
945 		break;
946 	}
947 }
948 
949 static pci_bridge_emul_read_status_t
950 advk_pci_bridge_emul_ext_conf_read(struct pci_bridge_emul *bridge,
951 				   int reg, u32 *value)
952 {
953 	struct advk_pcie *pcie = bridge->data;
954 
955 	switch (reg) {
956 	case 0:
957 		*value = advk_readl(pcie, PCIE_CORE_PCIERR_CAP + reg);
958 
959 		/*
960 		 * PCI_EXT_CAP_NEXT bits are set to offset 0x150, but Armada
961 		 * 3700 Functional Specification does not document registers
962 		 * at those addresses.
963 		 *
964 		 * Thus we clear PCI_EXT_CAP_NEXT bits to make Advanced Error
965 		 * Reporting Capability header the last Extended Capability.
966 		 * If we obtain documentation for those registers in the
967 		 * future, this can be changed.
968 		 */
969 		*value &= 0x000fffff;
970 		return PCI_BRIDGE_EMUL_HANDLED;
971 
972 	case PCI_ERR_UNCOR_STATUS:
973 	case PCI_ERR_UNCOR_MASK:
974 	case PCI_ERR_UNCOR_SEVER:
975 	case PCI_ERR_COR_STATUS:
976 	case PCI_ERR_COR_MASK:
977 	case PCI_ERR_CAP:
978 	case PCI_ERR_HEADER_LOG + 0:
979 	case PCI_ERR_HEADER_LOG + 4:
980 	case PCI_ERR_HEADER_LOG + 8:
981 	case PCI_ERR_HEADER_LOG + 12:
982 	case PCI_ERR_ROOT_COMMAND:
983 	case PCI_ERR_ROOT_STATUS:
984 	case PCI_ERR_ROOT_ERR_SRC:
985 		*value = advk_readl(pcie, PCIE_CORE_PCIERR_CAP + reg);
986 		return PCI_BRIDGE_EMUL_HANDLED;
987 
988 	default:
989 		return PCI_BRIDGE_EMUL_NOT_HANDLED;
990 	}
991 }
992 
993 static void
994 advk_pci_bridge_emul_ext_conf_write(struct pci_bridge_emul *bridge,
995 				    int reg, u32 old, u32 new, u32 mask)
996 {
997 	struct advk_pcie *pcie = bridge->data;
998 
999 	switch (reg) {
1000 	/* These are W1C registers, so clear other bits */
1001 	case PCI_ERR_UNCOR_STATUS:
1002 	case PCI_ERR_COR_STATUS:
1003 	case PCI_ERR_ROOT_STATUS:
1004 		new &= mask;
1005 		fallthrough;
1006 
1007 	case PCI_ERR_UNCOR_MASK:
1008 	case PCI_ERR_UNCOR_SEVER:
1009 	case PCI_ERR_COR_MASK:
1010 	case PCI_ERR_CAP:
1011 	case PCI_ERR_HEADER_LOG + 0:
1012 	case PCI_ERR_HEADER_LOG + 4:
1013 	case PCI_ERR_HEADER_LOG + 8:
1014 	case PCI_ERR_HEADER_LOG + 12:
1015 	case PCI_ERR_ROOT_COMMAND:
1016 	case PCI_ERR_ROOT_ERR_SRC:
1017 		advk_writel(pcie, new, PCIE_CORE_PCIERR_CAP + reg);
1018 		break;
1019 
1020 	default:
1021 		break;
1022 	}
1023 }
1024 
1025 static const struct pci_bridge_emul_ops advk_pci_bridge_emul_ops = {
1026 	.read_base = advk_pci_bridge_emul_base_conf_read,
1027 	.write_base = advk_pci_bridge_emul_base_conf_write,
1028 	.read_pcie = advk_pci_bridge_emul_pcie_conf_read,
1029 	.write_pcie = advk_pci_bridge_emul_pcie_conf_write,
1030 	.read_ext = advk_pci_bridge_emul_ext_conf_read,
1031 	.write_ext = advk_pci_bridge_emul_ext_conf_write,
1032 };
1033 
1034 /*
1035  * Initialize the configuration space of the PCI-to-PCI bridge
1036  * associated with the given PCIe interface.
1037  */
1038 static int advk_sw_pci_bridge_init(struct advk_pcie *pcie)
1039 {
1040 	struct pci_bridge_emul *bridge = &pcie->bridge;
1041 
1042 	bridge->conf.vendor =
1043 		cpu_to_le16(advk_readl(pcie, PCIE_CORE_DEV_ID_REG) & 0xffff);
1044 	bridge->conf.device =
1045 		cpu_to_le16(advk_readl(pcie, PCIE_CORE_DEV_ID_REG) >> 16);
1046 	bridge->conf.class_revision =
1047 		cpu_to_le32(advk_readl(pcie, PCIE_CORE_DEV_REV_REG) & 0xff);
1048 
1049 	/* Support 32 bits I/O addressing */
1050 	bridge->conf.iobase = PCI_IO_RANGE_TYPE_32;
1051 	bridge->conf.iolimit = PCI_IO_RANGE_TYPE_32;
1052 
1053 	/* Support 64 bits memory pref */
1054 	bridge->conf.pref_mem_base = cpu_to_le16(PCI_PREF_RANGE_TYPE_64);
1055 	bridge->conf.pref_mem_limit = cpu_to_le16(PCI_PREF_RANGE_TYPE_64);
1056 
1057 	/* Support interrupt A for MSI feature */
1058 	bridge->conf.intpin = PCI_INTERRUPT_INTA;
1059 
1060 	/*
1061 	 * Aardvark HW provides PCIe Capability structure in version 2 and
1062 	 * indicate slot support, which is emulated.
1063 	 */
1064 	bridge->pcie_conf.cap = cpu_to_le16(2 | PCI_EXP_FLAGS_SLOT);
1065 
1066 	/*
1067 	 * Set Presence Detect State bit permanently since there is no support
1068 	 * for unplugging the card nor detecting whether it is plugged. (If a
1069 	 * platform exists in the future that supports it, via a GPIO for
1070 	 * example, it should be implemented via this bit.)
1071 	 *
1072 	 * Set physical slot number to 1 since there is only one port and zero
1073 	 * value is reserved for ports within the same silicon as Root Port
1074 	 * which is not our case.
1075 	 */
1076 	bridge->pcie_conf.slotcap = cpu_to_le32(FIELD_PREP(PCI_EXP_SLTCAP_PSN,
1077 							   1));
1078 	bridge->pcie_conf.slotsta = cpu_to_le16(PCI_EXP_SLTSTA_PDS);
1079 
1080 	/* Indicates supports for Completion Retry Status */
1081 	bridge->pcie_conf.rootcap = cpu_to_le16(PCI_EXP_RTCAP_RRS_SV);
1082 
1083 	bridge->subsystem_vendor_id = advk_readl(pcie, PCIE_CORE_SSDEV_ID_REG) & 0xffff;
1084 	bridge->subsystem_id = advk_readl(pcie, PCIE_CORE_SSDEV_ID_REG) >> 16;
1085 	bridge->has_pcie = true;
1086 	bridge->pcie_start = PCIE_CORE_PCIEXP_CAP;
1087 	bridge->data = pcie;
1088 	bridge->ops = &advk_pci_bridge_emul_ops;
1089 
1090 	return pci_bridge_emul_init(bridge, 0);
1091 }
1092 
1093 static bool advk_pcie_valid_device(struct advk_pcie *pcie, struct pci_bus *bus,
1094 				  int devfn)
1095 {
1096 	if (pci_is_root_bus(bus) && PCI_SLOT(devfn) != 0)
1097 		return false;
1098 
1099 	/*
1100 	 * If the link goes down after we check for link-up, we have a problem:
1101 	 * if a PIO request is executed while link-down, the whole controller
1102 	 * gets stuck in a non-functional state, and even after link comes up
1103 	 * again, PIO requests won't work anymore, and a reset of the whole PCIe
1104 	 * controller is needed. Therefore we need to prevent sending PIO
1105 	 * requests while the link is down.
1106 	 */
1107 	if (!pci_is_root_bus(bus) && !advk_pcie_link_up(pcie))
1108 		return false;
1109 
1110 	return true;
1111 }
1112 
1113 static bool advk_pcie_pio_is_running(struct advk_pcie *pcie)
1114 {
1115 	struct device *dev = &pcie->pdev->dev;
1116 
1117 	/*
1118 	 * Trying to start a new PIO transfer when previous has not completed
1119 	 * cause External Abort on CPU which results in kernel panic:
1120 	 *
1121 	 *     SError Interrupt on CPU0, code 0xbf000002 -- SError
1122 	 *     Kernel panic - not syncing: Asynchronous SError Interrupt
1123 	 *
1124 	 * Functions advk_pcie_rd_conf() and advk_pcie_wr_conf() are protected
1125 	 * by raw_spin_lock_irqsave() at pci_lock_config() level to prevent
1126 	 * concurrent calls at the same time. But because PIO transfer may take
1127 	 * about 1.5s when link is down or card is disconnected, it means that
1128 	 * advk_pcie_wait_pio() does not always have to wait for completion.
1129 	 *
1130 	 * Some versions of ARM Trusted Firmware handles this External Abort at
1131 	 * EL3 level and mask it to prevent kernel panic. Relevant TF-A commit:
1132 	 * https://git.trustedfirmware.org/TF-A/trusted-firmware-a.git/commit/?id=3c7dcdac5c50
1133 	 */
1134 	if (advk_readl(pcie, PIO_START)) {
1135 		dev_err(dev, "Previous PIO read/write transfer is still running\n");
1136 		return true;
1137 	}
1138 
1139 	return false;
1140 }
1141 
1142 static int advk_pcie_rd_conf(struct pci_bus *bus, u32 devfn,
1143 			     int where, int size, u32 *val)
1144 {
1145 	struct advk_pcie *pcie = bus->sysdata;
1146 	int retry_count;
1147 	bool allow_rrs;
1148 	u32 reg;
1149 	int ret;
1150 
1151 	if (!advk_pcie_valid_device(pcie, bus, devfn))
1152 		return PCIBIOS_DEVICE_NOT_FOUND;
1153 
1154 	if (pci_is_root_bus(bus))
1155 		return pci_bridge_emul_conf_read(&pcie->bridge, where,
1156 						 size, val);
1157 
1158 	/*
1159 	 * Configuration Request Retry Status (RRS) is possible to return
1160 	 * only when reading both bytes from PCI_VENDOR_ID at once and
1161 	 * RRS_SVE flag on Root Port is enabled.
1162 	 */
1163 	allow_rrs = (where == PCI_VENDOR_ID) && (size >= 2) &&
1164 		    (le16_to_cpu(pcie->bridge.pcie_conf.rootctl) &
1165 		     PCI_EXP_RTCTL_RRS_SVE);
1166 
1167 	if (advk_pcie_pio_is_running(pcie))
1168 		goto try_rrs;
1169 
1170 	/* Program the control register */
1171 	reg = advk_readl(pcie, PIO_CTRL);
1172 	reg &= ~PIO_CTRL_TYPE_MASK;
1173 	if (pci_is_root_bus(bus->parent))
1174 		reg |= PCIE_CONFIG_RD_TYPE0;
1175 	else
1176 		reg |= PCIE_CONFIG_RD_TYPE1;
1177 	advk_writel(pcie, reg, PIO_CTRL);
1178 
1179 	/* Program the address registers */
1180 	reg = ALIGN_DOWN(PCIE_ECAM_OFFSET(bus->number, devfn, where), 4);
1181 	advk_writel(pcie, reg, PIO_ADDR_LS);
1182 	advk_writel(pcie, 0, PIO_ADDR_MS);
1183 
1184 	/* Program the data strobe */
1185 	advk_writel(pcie, 0xf, PIO_WR_DATA_STRB);
1186 
1187 	retry_count = 0;
1188 	do {
1189 		/* Clear PIO DONE ISR and start the transfer */
1190 		advk_writel(pcie, 1, PIO_ISR);
1191 		advk_writel(pcie, 1, PIO_START);
1192 
1193 		ret = advk_pcie_wait_pio(pcie);
1194 		if (ret < 0)
1195 			goto try_rrs;
1196 
1197 		retry_count += ret;
1198 
1199 		/* Check PIO status and get the read result */
1200 		ret = advk_pcie_check_pio_status(pcie, allow_rrs, val);
1201 	} while (ret == -EAGAIN && retry_count < PIO_RETRY_CNT);
1202 
1203 	if (ret < 0)
1204 		goto fail;
1205 
1206 	if (size == 1)
1207 		*val = (*val >> (8 * (where & 3))) & 0xff;
1208 	else if (size == 2)
1209 		*val = (*val >> (8 * (where & 3))) & 0xffff;
1210 
1211 	return PCIBIOS_SUCCESSFUL;
1212 
1213 try_rrs:
1214 	/*
1215 	 * If it is possible, return Configuration Request Retry Status so
1216 	 * that caller tries to issue the request again instead of failing.
1217 	 */
1218 	if (allow_rrs) {
1219 		*val = CFG_RD_RRS_VAL;
1220 		return PCIBIOS_SUCCESSFUL;
1221 	}
1222 
1223 fail:
1224 	*val = 0xffffffff;
1225 	return PCIBIOS_SET_FAILED;
1226 }
1227 
1228 static int advk_pcie_wr_conf(struct pci_bus *bus, u32 devfn,
1229 				int where, int size, u32 val)
1230 {
1231 	struct advk_pcie *pcie = bus->sysdata;
1232 	u32 reg;
1233 	u32 data_strobe = 0x0;
1234 	int retry_count;
1235 	int offset;
1236 	int ret;
1237 
1238 	if (!advk_pcie_valid_device(pcie, bus, devfn))
1239 		return PCIBIOS_DEVICE_NOT_FOUND;
1240 
1241 	if (pci_is_root_bus(bus))
1242 		return pci_bridge_emul_conf_write(&pcie->bridge, where,
1243 						  size, val);
1244 
1245 	if (where % size)
1246 		return PCIBIOS_SET_FAILED;
1247 
1248 	if (advk_pcie_pio_is_running(pcie))
1249 		return PCIBIOS_SET_FAILED;
1250 
1251 	/* Program the control register */
1252 	reg = advk_readl(pcie, PIO_CTRL);
1253 	reg &= ~PIO_CTRL_TYPE_MASK;
1254 	if (pci_is_root_bus(bus->parent))
1255 		reg |= PCIE_CONFIG_WR_TYPE0;
1256 	else
1257 		reg |= PCIE_CONFIG_WR_TYPE1;
1258 	advk_writel(pcie, reg, PIO_CTRL);
1259 
1260 	/* Program the address registers */
1261 	reg = ALIGN_DOWN(PCIE_ECAM_OFFSET(bus->number, devfn, where), 4);
1262 	advk_writel(pcie, reg, PIO_ADDR_LS);
1263 	advk_writel(pcie, 0, PIO_ADDR_MS);
1264 
1265 	/* Calculate the write strobe */
1266 	offset      = where & 0x3;
1267 	reg         = val << (8 * offset);
1268 	data_strobe = GENMASK(size - 1, 0) << offset;
1269 
1270 	/* Program the data register */
1271 	advk_writel(pcie, reg, PIO_WR_DATA);
1272 
1273 	/* Program the data strobe */
1274 	advk_writel(pcie, data_strobe, PIO_WR_DATA_STRB);
1275 
1276 	retry_count = 0;
1277 	do {
1278 		/* Clear PIO DONE ISR and start the transfer */
1279 		advk_writel(pcie, 1, PIO_ISR);
1280 		advk_writel(pcie, 1, PIO_START);
1281 
1282 		ret = advk_pcie_wait_pio(pcie);
1283 		if (ret < 0)
1284 			return PCIBIOS_SET_FAILED;
1285 
1286 		retry_count += ret;
1287 
1288 		ret = advk_pcie_check_pio_status(pcie, false, NULL);
1289 	} while (ret == -EAGAIN && retry_count < PIO_RETRY_CNT);
1290 
1291 	return ret < 0 ? PCIBIOS_SET_FAILED : PCIBIOS_SUCCESSFUL;
1292 }
1293 
1294 static struct pci_ops advk_pcie_ops = {
1295 	.read = advk_pcie_rd_conf,
1296 	.write = advk_pcie_wr_conf,
1297 };
1298 
1299 static void advk_msi_irq_compose_msi_msg(struct irq_data *data,
1300 					 struct msi_msg *msg)
1301 {
1302 	struct advk_pcie *pcie = irq_data_get_irq_chip_data(data);
1303 	phys_addr_t msi_addr = virt_to_phys(pcie);
1304 
1305 	msg->address_lo = lower_32_bits(msi_addr);
1306 	msg->address_hi = upper_32_bits(msi_addr);
1307 	msg->data = data->hwirq;
1308 }
1309 
1310 static void advk_msi_irq_mask(struct irq_data *d)
1311 {
1312 	struct advk_pcie *pcie = d->domain->host_data;
1313 	irq_hw_number_t hwirq = irqd_to_hwirq(d);
1314 	unsigned long flags;
1315 	u32 mask;
1316 
1317 	raw_spin_lock_irqsave(&pcie->msi_irq_lock, flags);
1318 	mask = advk_readl(pcie, PCIE_MSI_MASK_REG);
1319 	mask |= BIT(hwirq);
1320 	advk_writel(pcie, mask, PCIE_MSI_MASK_REG);
1321 	raw_spin_unlock_irqrestore(&pcie->msi_irq_lock, flags);
1322 }
1323 
1324 static void advk_msi_irq_unmask(struct irq_data *d)
1325 {
1326 	struct advk_pcie *pcie = d->domain->host_data;
1327 	irq_hw_number_t hwirq = irqd_to_hwirq(d);
1328 	unsigned long flags;
1329 	u32 mask;
1330 
1331 	raw_spin_lock_irqsave(&pcie->msi_irq_lock, flags);
1332 	mask = advk_readl(pcie, PCIE_MSI_MASK_REG);
1333 	mask &= ~BIT(hwirq);
1334 	advk_writel(pcie, mask, PCIE_MSI_MASK_REG);
1335 	raw_spin_unlock_irqrestore(&pcie->msi_irq_lock, flags);
1336 }
1337 
1338 static struct irq_chip advk_msi_bottom_irq_chip = {
1339 	.name			= "MSI",
1340 	.irq_compose_msi_msg	= advk_msi_irq_compose_msi_msg,
1341 	.irq_mask		= advk_msi_irq_mask,
1342 	.irq_unmask		= advk_msi_irq_unmask,
1343 };
1344 
1345 static int advk_msi_irq_domain_alloc(struct irq_domain *domain,
1346 				     unsigned int virq,
1347 				     unsigned int nr_irqs, void *args)
1348 {
1349 	struct advk_pcie *pcie = domain->host_data;
1350 	int hwirq, i;
1351 
1352 	mutex_lock(&pcie->msi_used_lock);
1353 	hwirq = bitmap_find_free_region(pcie->msi_used, MSI_IRQ_NUM,
1354 					order_base_2(nr_irqs));
1355 	mutex_unlock(&pcie->msi_used_lock);
1356 	if (hwirq < 0)
1357 		return -ENOSPC;
1358 
1359 	for (i = 0; i < nr_irqs; i++)
1360 		irq_domain_set_info(domain, virq + i, hwirq + i,
1361 				    &advk_msi_bottom_irq_chip,
1362 				    domain->host_data, handle_simple_irq,
1363 				    NULL, NULL);
1364 
1365 	return 0;
1366 }
1367 
1368 static void advk_msi_irq_domain_free(struct irq_domain *domain,
1369 				     unsigned int virq, unsigned int nr_irqs)
1370 {
1371 	struct irq_data *d = irq_domain_get_irq_data(domain, virq);
1372 	struct advk_pcie *pcie = domain->host_data;
1373 
1374 	mutex_lock(&pcie->msi_used_lock);
1375 	bitmap_release_region(pcie->msi_used, d->hwirq, order_base_2(nr_irqs));
1376 	mutex_unlock(&pcie->msi_used_lock);
1377 }
1378 
1379 static const struct irq_domain_ops advk_msi_domain_ops = {
1380 	.alloc = advk_msi_irq_domain_alloc,
1381 	.free = advk_msi_irq_domain_free,
1382 };
1383 
1384 static void advk_pcie_irq_mask(struct irq_data *d)
1385 {
1386 	struct advk_pcie *pcie = d->domain->host_data;
1387 	irq_hw_number_t hwirq = irqd_to_hwirq(d);
1388 	unsigned long flags;
1389 	u32 mask;
1390 
1391 	raw_spin_lock_irqsave(&pcie->irq_lock, flags);
1392 	mask = advk_readl(pcie, PCIE_ISR1_MASK_REG);
1393 	mask |= PCIE_ISR1_INTX_ASSERT(hwirq);
1394 	advk_writel(pcie, mask, PCIE_ISR1_MASK_REG);
1395 	raw_spin_unlock_irqrestore(&pcie->irq_lock, flags);
1396 }
1397 
1398 static void advk_pcie_irq_unmask(struct irq_data *d)
1399 {
1400 	struct advk_pcie *pcie = d->domain->host_data;
1401 	irq_hw_number_t hwirq = irqd_to_hwirq(d);
1402 	unsigned long flags;
1403 	u32 mask;
1404 
1405 	raw_spin_lock_irqsave(&pcie->irq_lock, flags);
1406 	mask = advk_readl(pcie, PCIE_ISR1_MASK_REG);
1407 	mask &= ~PCIE_ISR1_INTX_ASSERT(hwirq);
1408 	advk_writel(pcie, mask, PCIE_ISR1_MASK_REG);
1409 	raw_spin_unlock_irqrestore(&pcie->irq_lock, flags);
1410 }
1411 
1412 static int advk_pcie_irq_map(struct irq_domain *h,
1413 			     unsigned int virq, irq_hw_number_t hwirq)
1414 {
1415 	struct advk_pcie *pcie = h->host_data;
1416 
1417 	irq_set_status_flags(virq, IRQ_LEVEL);
1418 	irq_set_chip_and_handler(virq, &pcie->irq_chip,
1419 				 handle_level_irq);
1420 	irq_set_chip_data(virq, pcie);
1421 
1422 	return 0;
1423 }
1424 
1425 static const struct irq_domain_ops advk_pcie_irq_domain_ops = {
1426 	.map = advk_pcie_irq_map,
1427 	.xlate = irq_domain_xlate_onecell,
1428 };
1429 
1430 #define ADVK_MSI_FLAGS_REQUIRED (MSI_FLAG_USE_DEF_DOM_OPS	| \
1431 				 MSI_FLAG_USE_DEF_CHIP_OPS	| \
1432 				 MSI_FLAG_PCI_MSI_MASK_PARENT	| \
1433 				 MSI_FLAG_NO_AFFINITY)
1434 #define ADVK_MSI_FLAGS_SUPPORTED (MSI_GENERIC_FLAGS_MASK	| \
1435 				  MSI_FLAG_PCI_MSIX		| \
1436 				  MSI_FLAG_MULTI_PCI_MSI)
1437 
1438 static const struct msi_parent_ops advk_msi_parent_ops = {
1439 	.required_flags		= ADVK_MSI_FLAGS_REQUIRED,
1440 	.supported_flags	= ADVK_MSI_FLAGS_SUPPORTED,
1441 	.bus_select_token	= DOMAIN_BUS_PCI_MSI,
1442 	.prefix			= "advk-",
1443 	.init_dev_msi_info	= msi_lib_init_dev_msi_info,
1444 };
1445 
1446 static int advk_pcie_init_msi_irq_domain(struct advk_pcie *pcie)
1447 {
1448 	struct device *dev = &pcie->pdev->dev;
1449 
1450 	raw_spin_lock_init(&pcie->msi_irq_lock);
1451 	mutex_init(&pcie->msi_used_lock);
1452 
1453 	struct irq_domain_info info = {
1454 		.fwnode		= dev_fwnode(dev),
1455 		.ops		= &advk_msi_domain_ops,
1456 		.host_data	= pcie,
1457 		.size		= MSI_IRQ_NUM,
1458 	};
1459 
1460 	pcie->msi_inner_domain = msi_create_parent_irq_domain(&info, &advk_msi_parent_ops);
1461 	if (!pcie->msi_inner_domain)
1462 		return -ENOMEM;
1463 
1464 	return 0;
1465 }
1466 
1467 static void advk_pcie_remove_msi_irq_domain(struct advk_pcie *pcie)
1468 {
1469 	irq_domain_remove(pcie->msi_inner_domain);
1470 }
1471 
1472 static int advk_pcie_init_irq_domain(struct advk_pcie *pcie)
1473 {
1474 	struct device *dev = &pcie->pdev->dev;
1475 	struct device_node *node = dev->of_node;
1476 	struct device_node *pcie_intc_node;
1477 	struct irq_chip *irq_chip;
1478 	int ret = 0;
1479 
1480 	raw_spin_lock_init(&pcie->irq_lock);
1481 
1482 	pcie_intc_node =  of_get_next_child(node, NULL);
1483 	if (!pcie_intc_node) {
1484 		dev_err(dev, "No PCIe Intc node found\n");
1485 		return -ENODEV;
1486 	}
1487 
1488 	irq_chip = &pcie->irq_chip;
1489 
1490 	irq_chip->name = devm_kasprintf(dev, GFP_KERNEL, "%s-irq",
1491 					dev_name(dev));
1492 	if (!irq_chip->name) {
1493 		ret = -ENOMEM;
1494 		goto out_put_node;
1495 	}
1496 
1497 	irq_chip->irq_mask = advk_pcie_irq_mask;
1498 	irq_chip->irq_unmask = advk_pcie_irq_unmask;
1499 
1500 	pcie->irq_domain = irq_domain_create_linear(of_fwnode_handle(pcie_intc_node), PCI_NUM_INTX,
1501 						    &advk_pcie_irq_domain_ops, pcie);
1502 	if (!pcie->irq_domain) {
1503 		dev_err(dev, "Failed to get a INTx IRQ domain\n");
1504 		ret = -ENOMEM;
1505 		goto out_put_node;
1506 	}
1507 
1508 out_put_node:
1509 	of_node_put(pcie_intc_node);
1510 	return ret;
1511 }
1512 
1513 static void advk_pcie_remove_irq_domain(struct advk_pcie *pcie)
1514 {
1515 	irq_domain_remove(pcie->irq_domain);
1516 }
1517 
1518 static struct irq_chip advk_rp_irq_chip = {
1519 	.name = "advk-RP",
1520 };
1521 
1522 static int advk_pcie_rp_irq_map(struct irq_domain *h,
1523 				unsigned int virq, irq_hw_number_t hwirq)
1524 {
1525 	struct advk_pcie *pcie = h->host_data;
1526 
1527 	irq_set_chip_and_handler(virq, &advk_rp_irq_chip, handle_simple_irq);
1528 	irq_set_chip_data(virq, pcie);
1529 
1530 	return 0;
1531 }
1532 
1533 static const struct irq_domain_ops advk_pcie_rp_irq_domain_ops = {
1534 	.map = advk_pcie_rp_irq_map,
1535 	.xlate = irq_domain_xlate_onecell,
1536 };
1537 
1538 static int advk_pcie_init_rp_irq_domain(struct advk_pcie *pcie)
1539 {
1540 	pcie->rp_irq_domain = irq_domain_create_linear(NULL, 1, &advk_pcie_rp_irq_domain_ops, pcie);
1541 	if (!pcie->rp_irq_domain) {
1542 		dev_err(&pcie->pdev->dev, "Failed to add Root Port IRQ domain\n");
1543 		return -ENOMEM;
1544 	}
1545 
1546 	return 0;
1547 }
1548 
1549 static void advk_pcie_remove_rp_irq_domain(struct advk_pcie *pcie)
1550 {
1551 	irq_domain_remove(pcie->rp_irq_domain);
1552 }
1553 
1554 static void advk_pcie_handle_pme(struct advk_pcie *pcie)
1555 {
1556 	u32 requester = advk_readl(pcie, PCIE_MSG_LOG_REG) >> 16;
1557 
1558 	advk_writel(pcie, PCIE_MSG_PM_PME_MASK, PCIE_ISR0_REG);
1559 
1560 	/*
1561 	 * PCIE_MSG_LOG_REG contains the last inbound message, so store
1562 	 * the requester ID only when PME was not asserted yet.
1563 	 * Also do not trigger PME interrupt when PME is still asserted.
1564 	 */
1565 	if (!(le32_to_cpu(pcie->bridge.pcie_conf.rootsta) & PCI_EXP_RTSTA_PME)) {
1566 		pcie->bridge.pcie_conf.rootsta = cpu_to_le32(requester | PCI_EXP_RTSTA_PME);
1567 
1568 		/*
1569 		 * Trigger PME interrupt only if PMEIE bit in Root Control is set.
1570 		 * Aardvark HW returns zero for PCI_EXP_FLAGS_IRQ, so use PCIe interrupt 0.
1571 		 */
1572 		if (!(le16_to_cpu(pcie->bridge.pcie_conf.rootctl) & PCI_EXP_RTCTL_PMEIE))
1573 			return;
1574 
1575 		if (generic_handle_domain_irq(pcie->rp_irq_domain, 0) == -EINVAL)
1576 			dev_err_ratelimited(&pcie->pdev->dev, "unhandled PME IRQ\n");
1577 	}
1578 }
1579 
1580 static void advk_pcie_handle_msi(struct advk_pcie *pcie)
1581 {
1582 	u32 msi_val, msi_mask, msi_status, msi_idx;
1583 
1584 	msi_mask = advk_readl(pcie, PCIE_MSI_MASK_REG);
1585 	msi_val = advk_readl(pcie, PCIE_MSI_STATUS_REG);
1586 	msi_status = msi_val & ((~msi_mask) & PCIE_MSI_ALL_MASK);
1587 
1588 	for (msi_idx = 0; msi_idx < MSI_IRQ_NUM; msi_idx++) {
1589 		if (!(BIT(msi_idx) & msi_status))
1590 			continue;
1591 
1592 		advk_writel(pcie, BIT(msi_idx), PCIE_MSI_STATUS_REG);
1593 		if (generic_handle_domain_irq(pcie->msi_inner_domain, msi_idx) == -EINVAL)
1594 			dev_err_ratelimited(&pcie->pdev->dev, "unexpected MSI 0x%02x\n", msi_idx);
1595 	}
1596 
1597 	advk_writel(pcie, PCIE_ISR0_MSI_INT_PENDING,
1598 		    PCIE_ISR0_REG);
1599 }
1600 
1601 static void advk_pcie_handle_int(struct advk_pcie *pcie)
1602 {
1603 	u32 isr0_val, isr0_mask, isr0_status;
1604 	u32 isr1_val, isr1_mask, isr1_status;
1605 	int i;
1606 
1607 	isr0_val = advk_readl(pcie, PCIE_ISR0_REG);
1608 	isr0_mask = advk_readl(pcie, PCIE_ISR0_MASK_REG);
1609 	isr0_status = isr0_val & ((~isr0_mask) & PCIE_ISR0_ALL_MASK);
1610 
1611 	isr1_val = advk_readl(pcie, PCIE_ISR1_REG);
1612 	isr1_mask = advk_readl(pcie, PCIE_ISR1_MASK_REG);
1613 	isr1_status = isr1_val & ((~isr1_mask) & PCIE_ISR1_ALL_MASK);
1614 
1615 	/* Process PME interrupt as the first one to do not miss PME requester id */
1616 	if (isr0_status & PCIE_MSG_PM_PME_MASK)
1617 		advk_pcie_handle_pme(pcie);
1618 
1619 	/* Process ERR interrupt */
1620 	if (isr0_status & PCIE_ISR0_ERR_MASK) {
1621 		advk_writel(pcie, PCIE_ISR0_ERR_MASK, PCIE_ISR0_REG);
1622 
1623 		/*
1624 		 * Aardvark HW returns zero for PCI_ERR_ROOT_AER_IRQ, so use
1625 		 * PCIe interrupt 0
1626 		 */
1627 		if (generic_handle_domain_irq(pcie->rp_irq_domain, 0) == -EINVAL)
1628 			dev_err_ratelimited(&pcie->pdev->dev, "unhandled ERR IRQ\n");
1629 	}
1630 
1631 	/* Process MSI interrupts */
1632 	if (isr0_status & PCIE_ISR0_MSI_INT_PENDING)
1633 		advk_pcie_handle_msi(pcie);
1634 
1635 	/* Process legacy interrupts */
1636 	for (i = 0; i < PCI_NUM_INTX; i++) {
1637 		if (!(isr1_status & PCIE_ISR1_INTX_ASSERT(i)))
1638 			continue;
1639 
1640 		advk_writel(pcie, PCIE_ISR1_INTX_ASSERT(i),
1641 			    PCIE_ISR1_REG);
1642 
1643 		if (generic_handle_domain_irq(pcie->irq_domain, i) == -EINVAL)
1644 			dev_err_ratelimited(&pcie->pdev->dev, "unexpected INT%c IRQ\n",
1645 					    (char)i + 'A');
1646 	}
1647 }
1648 
1649 static irqreturn_t advk_pcie_irq_handler(int irq, void *arg)
1650 {
1651 	struct advk_pcie *pcie = arg;
1652 	u32 status;
1653 
1654 	status = advk_readl(pcie, HOST_CTRL_INT_STATUS_REG);
1655 	if (!(status & PCIE_IRQ_CORE_INT))
1656 		return IRQ_NONE;
1657 
1658 	advk_pcie_handle_int(pcie);
1659 
1660 	/* Clear interrupt */
1661 	advk_writel(pcie, PCIE_IRQ_CORE_INT, HOST_CTRL_INT_STATUS_REG);
1662 
1663 	return IRQ_HANDLED;
1664 }
1665 
1666 static int advk_pcie_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
1667 {
1668 	struct advk_pcie *pcie = dev->bus->sysdata;
1669 
1670 	/*
1671 	 * Emulated root bridge has its own emulated irq chip and irq domain.
1672 	 * Argument pin is the INTx pin (1=INTA, 2=INTB, 3=INTC, 4=INTD) and
1673 	 * hwirq for irq_create_mapping() is indexed from zero.
1674 	 */
1675 	if (pci_is_root_bus(dev->bus))
1676 		return irq_create_mapping(pcie->rp_irq_domain, pin - 1);
1677 	else
1678 		return of_irq_parse_and_map_pci(dev, slot, pin);
1679 }
1680 
1681 static void advk_pcie_disable_phy(struct advk_pcie *pcie)
1682 {
1683 	phy_power_off(pcie->phy);
1684 	phy_exit(pcie->phy);
1685 }
1686 
1687 static int advk_pcie_enable_phy(struct advk_pcie *pcie)
1688 {
1689 	int ret;
1690 
1691 	if (!pcie->phy)
1692 		return 0;
1693 
1694 	ret = phy_init(pcie->phy);
1695 	if (ret)
1696 		return ret;
1697 
1698 	ret = phy_set_mode(pcie->phy, PHY_MODE_PCIE);
1699 	if (ret) {
1700 		phy_exit(pcie->phy);
1701 		return ret;
1702 	}
1703 
1704 	ret = phy_power_on(pcie->phy);
1705 	if (ret) {
1706 		phy_exit(pcie->phy);
1707 		return ret;
1708 	}
1709 
1710 	return 0;
1711 }
1712 
1713 static int advk_pcie_setup_phy(struct advk_pcie *pcie)
1714 {
1715 	struct device *dev = &pcie->pdev->dev;
1716 	struct device_node *node = dev->of_node;
1717 	int ret = 0;
1718 
1719 	pcie->phy = devm_of_phy_get(dev, node, NULL);
1720 	if (IS_ERR(pcie->phy) && (PTR_ERR(pcie->phy) == -EPROBE_DEFER))
1721 		return PTR_ERR(pcie->phy);
1722 
1723 	/* Old bindings miss the PHY handle */
1724 	if (IS_ERR(pcie->phy)) {
1725 		dev_warn(dev, "PHY unavailable (%ld)\n", PTR_ERR(pcie->phy));
1726 		pcie->phy = NULL;
1727 		return 0;
1728 	}
1729 
1730 	ret = advk_pcie_enable_phy(pcie);
1731 	if (ret)
1732 		dev_err(dev, "Failed to initialize PHY (%d)\n", ret);
1733 
1734 	return ret;
1735 }
1736 
1737 static int advk_pcie_probe(struct platform_device *pdev)
1738 {
1739 	struct device *dev = &pdev->dev;
1740 	struct advk_pcie *pcie;
1741 	struct pci_host_bridge *bridge;
1742 	struct resource_entry *entry;
1743 	int ret, irq;
1744 
1745 	bridge = devm_pci_alloc_host_bridge(dev, sizeof(struct advk_pcie));
1746 	if (!bridge)
1747 		return -ENOMEM;
1748 
1749 	pcie = pci_host_bridge_priv(bridge);
1750 	pcie->pdev = pdev;
1751 	platform_set_drvdata(pdev, pcie);
1752 
1753 	resource_list_for_each_entry(entry, &bridge->windows) {
1754 		resource_size_t start = entry->res->start;
1755 		resource_size_t size = resource_size(entry->res);
1756 		unsigned long type = resource_type(entry->res);
1757 		u64 win_size;
1758 
1759 		/*
1760 		 * Aardvark hardware allows to configure also PCIe window
1761 		 * for config type 0 and type 1 mapping, but driver uses
1762 		 * only PIO for issuing configuration transfers which does
1763 		 * not use PCIe window configuration.
1764 		 */
1765 		if (type != IORESOURCE_MEM && type != IORESOURCE_IO)
1766 			continue;
1767 
1768 		/*
1769 		 * Skip transparent memory resources. Default outbound access
1770 		 * configuration is set to transparent memory access so it
1771 		 * does not need window configuration.
1772 		 */
1773 		if (type == IORESOURCE_MEM && entry->offset == 0)
1774 			continue;
1775 
1776 		/*
1777 		 * The n-th PCIe window is configured by tuple (match, remap, mask)
1778 		 * and an access to address A uses this window if A matches the
1779 		 * match with given mask.
1780 		 * So every PCIe window size must be a power of two and every start
1781 		 * address must be aligned to window size. Minimal size is 64 KiB
1782 		 * because lower 16 bits of mask must be zero. Remapped address
1783 		 * may have set only bits from the mask.
1784 		 */
1785 		while (pcie->wins_count < OB_WIN_COUNT && size > 0) {
1786 			/* Calculate the largest aligned window size */
1787 			win_size = (1ULL << (fls64(size)-1)) |
1788 				   (start ? (1ULL << __ffs64(start)) : 0);
1789 			win_size = 1ULL << __ffs64(win_size);
1790 			if (win_size < 0x10000)
1791 				break;
1792 
1793 			dev_dbg(dev,
1794 				"Configuring PCIe window %d: [0x%llx-0x%llx] as %lu\n",
1795 				pcie->wins_count, (unsigned long long)start,
1796 				(unsigned long long)start + win_size, type);
1797 
1798 			if (type == IORESOURCE_IO) {
1799 				pcie->wins[pcie->wins_count].actions = OB_WIN_TYPE_IO;
1800 				pcie->wins[pcie->wins_count].match = pci_pio_to_address(start);
1801 			} else {
1802 				pcie->wins[pcie->wins_count].actions = OB_WIN_TYPE_MEM;
1803 				pcie->wins[pcie->wins_count].match = start;
1804 			}
1805 			pcie->wins[pcie->wins_count].remap = start - entry->offset;
1806 			pcie->wins[pcie->wins_count].mask = ~(win_size - 1);
1807 
1808 			if (pcie->wins[pcie->wins_count].remap & (win_size - 1))
1809 				break;
1810 
1811 			start += win_size;
1812 			size -= win_size;
1813 			pcie->wins_count++;
1814 		}
1815 
1816 		if (size > 0) {
1817 			dev_err(&pcie->pdev->dev,
1818 				"Invalid PCIe region [0x%llx-0x%llx]\n",
1819 				(unsigned long long)entry->res->start,
1820 				(unsigned long long)entry->res->end + 1);
1821 			return -EINVAL;
1822 		}
1823 	}
1824 
1825 	pcie->base = devm_platform_ioremap_resource(pdev, 0);
1826 	if (IS_ERR(pcie->base))
1827 		return PTR_ERR(pcie->base);
1828 
1829 	irq = platform_get_irq(pdev, 0);
1830 	if (irq < 0)
1831 		return irq;
1832 
1833 	ret = devm_request_irq(dev, irq, advk_pcie_irq_handler,
1834 			       IRQF_SHARED | IRQF_NO_THREAD, "advk-pcie",
1835 			       pcie);
1836 	if (ret) {
1837 		dev_err(dev, "Failed to register interrupt\n");
1838 		return ret;
1839 	}
1840 
1841 	pcie->reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
1842 	ret = PTR_ERR_OR_ZERO(pcie->reset_gpio);
1843 	if (ret) {
1844 		if (ret != -EPROBE_DEFER)
1845 			dev_err(dev, "Failed to get reset-gpio: %i\n", ret);
1846 		return ret;
1847 	}
1848 
1849 	ret = gpiod_set_consumer_name(pcie->reset_gpio, "pcie1-reset");
1850 	if (ret) {
1851 		dev_err(dev, "Failed to set reset gpio name: %d\n", ret);
1852 		return ret;
1853 	}
1854 
1855 	ret = of_pci_get_max_link_speed(dev->of_node);
1856 	if (ret <= 0 || ret > 3)
1857 		pcie->link_gen = 3;
1858 	else
1859 		pcie->link_gen = ret;
1860 
1861 	ret = advk_pcie_setup_phy(pcie);
1862 	if (ret)
1863 		return ret;
1864 
1865 	advk_pcie_setup_hw(pcie);
1866 
1867 	ret = advk_sw_pci_bridge_init(pcie);
1868 	if (ret) {
1869 		dev_err(dev, "Failed to register emulated root PCI bridge\n");
1870 		return ret;
1871 	}
1872 
1873 	ret = advk_pcie_init_irq_domain(pcie);
1874 	if (ret) {
1875 		dev_err(dev, "Failed to initialize irq\n");
1876 		return ret;
1877 	}
1878 
1879 	ret = advk_pcie_init_msi_irq_domain(pcie);
1880 	if (ret) {
1881 		dev_err(dev, "Failed to initialize irq\n");
1882 		advk_pcie_remove_irq_domain(pcie);
1883 		return ret;
1884 	}
1885 
1886 	ret = advk_pcie_init_rp_irq_domain(pcie);
1887 	if (ret) {
1888 		dev_err(dev, "Failed to initialize irq\n");
1889 		advk_pcie_remove_msi_irq_domain(pcie);
1890 		advk_pcie_remove_irq_domain(pcie);
1891 		return ret;
1892 	}
1893 
1894 	bridge->sysdata = pcie;
1895 	bridge->ops = &advk_pcie_ops;
1896 	bridge->map_irq = advk_pcie_map_irq;
1897 
1898 	ret = pci_host_probe(bridge);
1899 	if (ret < 0) {
1900 		advk_pcie_remove_rp_irq_domain(pcie);
1901 		advk_pcie_remove_msi_irq_domain(pcie);
1902 		advk_pcie_remove_irq_domain(pcie);
1903 		return ret;
1904 	}
1905 
1906 	return 0;
1907 }
1908 
1909 static void advk_pcie_remove(struct platform_device *pdev)
1910 {
1911 	struct advk_pcie *pcie = platform_get_drvdata(pdev);
1912 	struct pci_host_bridge *bridge = pci_host_bridge_from_priv(pcie);
1913 	u32 val;
1914 	int i;
1915 
1916 	/* Remove PCI bus with all devices */
1917 	pci_lock_rescan_remove();
1918 	pci_stop_root_bus(bridge->bus);
1919 	pci_remove_root_bus(bridge->bus);
1920 	pci_unlock_rescan_remove();
1921 
1922 	/* Disable Root Bridge I/O space, memory space and bus mastering */
1923 	val = advk_readl(pcie, PCIE_CORE_CMD_STATUS_REG);
1924 	val &= ~(PCI_COMMAND_IO | PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER);
1925 	advk_writel(pcie, val, PCIE_CORE_CMD_STATUS_REG);
1926 
1927 	/* Disable MSI */
1928 	val = advk_readl(pcie, PCIE_CORE_CTRL2_REG);
1929 	val &= ~PCIE_CORE_CTRL2_MSI_ENABLE;
1930 	advk_writel(pcie, val, PCIE_CORE_CTRL2_REG);
1931 
1932 	/* Clear MSI address */
1933 	advk_writel(pcie, 0, PCIE_MSI_ADDR_LOW_REG);
1934 	advk_writel(pcie, 0, PCIE_MSI_ADDR_HIGH_REG);
1935 
1936 	/* Mask all interrupts */
1937 	advk_writel(pcie, PCIE_MSI_ALL_MASK, PCIE_MSI_MASK_REG);
1938 	advk_writel(pcie, PCIE_ISR0_ALL_MASK, PCIE_ISR0_MASK_REG);
1939 	advk_writel(pcie, PCIE_ISR1_ALL_MASK, PCIE_ISR1_MASK_REG);
1940 	advk_writel(pcie, PCIE_IRQ_ALL_MASK, HOST_CTRL_INT_MASK_REG);
1941 
1942 	/* Clear all interrupts */
1943 	advk_writel(pcie, PCIE_MSI_ALL_MASK, PCIE_MSI_STATUS_REG);
1944 	advk_writel(pcie, PCIE_ISR0_ALL_MASK, PCIE_ISR0_REG);
1945 	advk_writel(pcie, PCIE_ISR1_ALL_MASK, PCIE_ISR1_REG);
1946 	advk_writel(pcie, PCIE_IRQ_ALL_MASK, HOST_CTRL_INT_STATUS_REG);
1947 
1948 	/* Remove IRQ domains */
1949 	advk_pcie_remove_rp_irq_domain(pcie);
1950 	advk_pcie_remove_msi_irq_domain(pcie);
1951 	advk_pcie_remove_irq_domain(pcie);
1952 
1953 	/* Free config space for emulated root bridge */
1954 	pci_bridge_emul_cleanup(&pcie->bridge);
1955 
1956 	/* Assert PERST# signal which prepares PCIe card for power down */
1957 	if (pcie->reset_gpio)
1958 		gpiod_set_value_cansleep(pcie->reset_gpio, 1);
1959 
1960 	/* Disable link training */
1961 	val = advk_readl(pcie, PCIE_CORE_CTRL0_REG);
1962 	val &= ~LINK_TRAINING_EN;
1963 	advk_writel(pcie, val, PCIE_CORE_CTRL0_REG);
1964 
1965 	/* Disable outbound address windows mapping */
1966 	for (i = 0; i < OB_WIN_COUNT; i++)
1967 		advk_pcie_disable_ob_win(pcie, i);
1968 
1969 	/* Disable phy */
1970 	advk_pcie_disable_phy(pcie);
1971 }
1972 
1973 static const struct of_device_id advk_pcie_of_match_table[] = {
1974 	{ .compatible = "marvell,armada-3700-pcie", },
1975 	{},
1976 };
1977 MODULE_DEVICE_TABLE(of, advk_pcie_of_match_table);
1978 
1979 static struct platform_driver advk_pcie_driver = {
1980 	.driver = {
1981 		.name = "advk-pcie",
1982 		.of_match_table = advk_pcie_of_match_table,
1983 	},
1984 	.probe = advk_pcie_probe,
1985 	.remove = advk_pcie_remove,
1986 };
1987 module_platform_driver(advk_pcie_driver);
1988 
1989 MODULE_DESCRIPTION("Aardvark PCIe controller");
1990 MODULE_LICENSE("GPL v2");
1991