1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Support for V3 Semiconductor PCI Local Bus to PCI Bridge
4  * Copyright (C) 2017 Linus Walleij <linus.walleij@linaro.org>
5  *
6  * Based on the code from arch/arm/mach-integrator/pci_v3.c
7  * Copyright (C) 1999 ARM Limited
8  * Copyright (C) 2000-2001 Deep Blue Solutions Ltd
9  *
10  * Contributors to the old driver include:
11  * Russell King <linux@armlinux.org.uk>
12  * David A. Rusling <david.rusling@linaro.org> (uHAL, ARM Firmware suite)
13  * Rob Herring <robh@kernel.org>
14  * Liviu Dudau <Liviu.Dudau@arm.com>
15  * Grant Likely <grant.likely@secretlab.ca>
16  * Arnd Bergmann <arnd@arndb.de>
17  * Bjorn Helgaas <bhelgaas@google.com>
18  */
19 #include <linux/init.h>
20 #include <linux/interrupt.h>
21 #include <linux/io.h>
22 #include <linux/kernel.h>
23 #include <linux/of_address.h>
24 #include <linux/of_device.h>
25 #include <linux/of_irq.h>
26 #include <linux/of_pci.h>
27 #include <linux/pci.h>
28 #include <linux/platform_device.h>
29 #include <linux/slab.h>
30 #include <linux/bitops.h>
31 #include <linux/irq.h>
32 #include <linux/mfd/syscon.h>
33 #include <linux/regmap.h>
34 #include <linux/clk.h>
35 
36 #include "../pci.h"
37 
38 #define V3_PCI_VENDOR			0x00000000
39 #define V3_PCI_DEVICE			0x00000002
40 #define V3_PCI_CMD			0x00000004
41 #define V3_PCI_STAT			0x00000006
42 #define V3_PCI_CC_REV			0x00000008
43 #define V3_PCI_HDR_CFG			0x0000000C
44 #define V3_PCI_IO_BASE			0x00000010
45 #define V3_PCI_BASE0			0x00000014
46 #define V3_PCI_BASE1			0x00000018
47 #define V3_PCI_SUB_VENDOR		0x0000002C
48 #define V3_PCI_SUB_ID			0x0000002E
49 #define V3_PCI_ROM			0x00000030
50 #define V3_PCI_BPARAM			0x0000003C
51 #define V3_PCI_MAP0			0x00000040
52 #define V3_PCI_MAP1			0x00000044
53 #define V3_PCI_INT_STAT			0x00000048
54 #define V3_PCI_INT_CFG			0x0000004C
55 #define V3_LB_BASE0			0x00000054
56 #define V3_LB_BASE1			0x00000058
57 #define V3_LB_MAP0			0x0000005E
58 #define V3_LB_MAP1			0x00000062
59 #define V3_LB_BASE2			0x00000064
60 #define V3_LB_MAP2			0x00000066
61 #define V3_LB_SIZE			0x00000068
62 #define V3_LB_IO_BASE			0x0000006E
63 #define V3_FIFO_CFG			0x00000070
64 #define V3_FIFO_PRIORITY		0x00000072
65 #define V3_FIFO_STAT			0x00000074
66 #define V3_LB_ISTAT			0x00000076
67 #define V3_LB_IMASK			0x00000077
68 #define V3_SYSTEM			0x00000078
69 #define V3_LB_CFG			0x0000007A
70 #define V3_PCI_CFG			0x0000007C
71 #define V3_DMA_PCI_ADR0			0x00000080
72 #define V3_DMA_PCI_ADR1			0x00000090
73 #define V3_DMA_LOCAL_ADR0		0x00000084
74 #define V3_DMA_LOCAL_ADR1		0x00000094
75 #define V3_DMA_LENGTH0			0x00000088
76 #define V3_DMA_LENGTH1			0x00000098
77 #define V3_DMA_CSR0			0x0000008B
78 #define V3_DMA_CSR1			0x0000009B
79 #define V3_DMA_CTLB_ADR0		0x0000008C
80 #define V3_DMA_CTLB_ADR1		0x0000009C
81 #define V3_DMA_DELAY			0x000000E0
82 #define V3_MAIL_DATA			0x000000C0
83 #define V3_PCI_MAIL_IEWR		0x000000D0
84 #define V3_PCI_MAIL_IERD		0x000000D2
85 #define V3_LB_MAIL_IEWR			0x000000D4
86 #define V3_LB_MAIL_IERD			0x000000D6
87 #define V3_MAIL_WR_STAT			0x000000D8
88 #define V3_MAIL_RD_STAT			0x000000DA
89 #define V3_QBA_MAP			0x000000DC
90 
91 /* PCI STATUS bits */
92 #define V3_PCI_STAT_PAR_ERR		BIT(15)
93 #define V3_PCI_STAT_SYS_ERR		BIT(14)
94 #define V3_PCI_STAT_M_ABORT_ERR		BIT(13)
95 #define V3_PCI_STAT_T_ABORT_ERR		BIT(12)
96 
97 /* LB ISTAT bits */
98 #define V3_LB_ISTAT_MAILBOX		BIT(7)
99 #define V3_LB_ISTAT_PCI_RD		BIT(6)
100 #define V3_LB_ISTAT_PCI_WR		BIT(5)
101 #define V3_LB_ISTAT_PCI_INT		BIT(4)
102 #define V3_LB_ISTAT_PCI_PERR		BIT(3)
103 #define V3_LB_ISTAT_I2O_QWR		BIT(2)
104 #define V3_LB_ISTAT_DMA1		BIT(1)
105 #define V3_LB_ISTAT_DMA0		BIT(0)
106 
107 /* PCI COMMAND bits */
108 #define V3_COMMAND_M_FBB_EN		BIT(9)
109 #define V3_COMMAND_M_SERR_EN		BIT(8)
110 #define V3_COMMAND_M_PAR_EN		BIT(6)
111 #define V3_COMMAND_M_MASTER_EN		BIT(2)
112 #define V3_COMMAND_M_MEM_EN		BIT(1)
113 #define V3_COMMAND_M_IO_EN		BIT(0)
114 
115 /* SYSTEM bits */
116 #define V3_SYSTEM_M_RST_OUT		BIT(15)
117 #define V3_SYSTEM_M_LOCK		BIT(14)
118 #define V3_SYSTEM_UNLOCK		0xa05f
119 
120 /* PCI CFG bits */
121 #define V3_PCI_CFG_M_I2O_EN		BIT(15)
122 #define V3_PCI_CFG_M_IO_REG_DIS		BIT(14)
123 #define V3_PCI_CFG_M_IO_DIS		BIT(13)
124 #define V3_PCI_CFG_M_EN3V		BIT(12)
125 #define V3_PCI_CFG_M_RETRY_EN		BIT(10)
126 #define V3_PCI_CFG_M_AD_LOW1		BIT(9)
127 #define V3_PCI_CFG_M_AD_LOW0		BIT(8)
128 /*
129  * This is the value applied to C/BE[3:1], with bit 0 always held 0
130  * during DMA access.
131  */
132 #define V3_PCI_CFG_M_RTYPE_SHIFT	5
133 #define V3_PCI_CFG_M_WTYPE_SHIFT	1
134 #define V3_PCI_CFG_TYPE_DEFAULT		0x3
135 
136 /* PCI BASE bits (PCI -> Local Bus) */
137 #define V3_PCI_BASE_M_ADR_BASE		0xFFF00000U
138 #define V3_PCI_BASE_M_ADR_BASEL		0x000FFF00U
139 #define V3_PCI_BASE_M_PREFETCH		BIT(3)
140 #define V3_PCI_BASE_M_TYPE		(3 << 1)
141 #define V3_PCI_BASE_M_IO		BIT(0)
142 
143 /* PCI MAP bits (PCI -> Local bus) */
144 #define V3_PCI_MAP_M_MAP_ADR		0xFFF00000U
145 #define V3_PCI_MAP_M_RD_POST_INH	BIT(15)
146 #define V3_PCI_MAP_M_ROM_SIZE		(3 << 10)
147 #define V3_PCI_MAP_M_SWAP		(3 << 8)
148 #define V3_PCI_MAP_M_ADR_SIZE		0x000000F0U
149 #define V3_PCI_MAP_M_REG_EN		BIT(1)
150 #define V3_PCI_MAP_M_ENABLE		BIT(0)
151 
152 /* LB_BASE0,1 bits (Local bus -> PCI) */
153 #define V3_LB_BASE_ADR_BASE		0xfff00000U
154 #define V3_LB_BASE_SWAP			(3 << 8)
155 #define V3_LB_BASE_ADR_SIZE		(15 << 4)
156 #define V3_LB_BASE_PREFETCH		BIT(3)
157 #define V3_LB_BASE_ENABLE		BIT(0)
158 
159 #define V3_LB_BASE_ADR_SIZE_1MB		(0 << 4)
160 #define V3_LB_BASE_ADR_SIZE_2MB		(1 << 4)
161 #define V3_LB_BASE_ADR_SIZE_4MB		(2 << 4)
162 #define V3_LB_BASE_ADR_SIZE_8MB		(3 << 4)
163 #define V3_LB_BASE_ADR_SIZE_16MB	(4 << 4)
164 #define V3_LB_BASE_ADR_SIZE_32MB	(5 << 4)
165 #define V3_LB_BASE_ADR_SIZE_64MB	(6 << 4)
166 #define V3_LB_BASE_ADR_SIZE_128MB	(7 << 4)
167 #define V3_LB_BASE_ADR_SIZE_256MB	(8 << 4)
168 #define V3_LB_BASE_ADR_SIZE_512MB	(9 << 4)
169 #define V3_LB_BASE_ADR_SIZE_1GB		(10 << 4)
170 #define V3_LB_BASE_ADR_SIZE_2GB		(11 << 4)
171 
172 #define v3_addr_to_lb_base(a)	((a) & V3_LB_BASE_ADR_BASE)
173 
174 /* LB_MAP0,1 bits (Local bus -> PCI) */
175 #define V3_LB_MAP_MAP_ADR		0xfff0U
176 #define V3_LB_MAP_TYPE			(7 << 1)
177 #define V3_LB_MAP_AD_LOW_EN		BIT(0)
178 
179 #define V3_LB_MAP_TYPE_IACK		(0 << 1)
180 #define V3_LB_MAP_TYPE_IO		(1 << 1)
181 #define V3_LB_MAP_TYPE_MEM		(3 << 1)
182 #define V3_LB_MAP_TYPE_CONFIG		(5 << 1)
183 #define V3_LB_MAP_TYPE_MEM_MULTIPLE	(6 << 1)
184 
185 #define v3_addr_to_lb_map(a)	(((a) >> 16) & V3_LB_MAP_MAP_ADR)
186 
187 /* LB_BASE2 bits (Local bus -> PCI IO) */
188 #define V3_LB_BASE2_ADR_BASE		0xff00U
189 #define V3_LB_BASE2_SWAP_AUTO		(3 << 6)
190 #define V3_LB_BASE2_ENABLE		BIT(0)
191 
192 #define v3_addr_to_lb_base2(a)	(((a) >> 16) & V3_LB_BASE2_ADR_BASE)
193 
194 /* LB_MAP2 bits (Local bus -> PCI IO) */
195 #define V3_LB_MAP2_MAP_ADR		0xff00U
196 
197 #define v3_addr_to_lb_map2(a)	(((a) >> 16) & V3_LB_MAP2_MAP_ADR)
198 
199 /* FIFO priority bits */
200 #define V3_FIFO_PRIO_LOCAL		BIT(12)
201 #define V3_FIFO_PRIO_LB_RD1_FLUSH_EOB	BIT(10)
202 #define V3_FIFO_PRIO_LB_RD1_FLUSH_AP1	BIT(11)
203 #define V3_FIFO_PRIO_LB_RD1_FLUSH_ANY	(BIT(10)|BIT(11))
204 #define V3_FIFO_PRIO_LB_RD0_FLUSH_EOB	BIT(8)
205 #define V3_FIFO_PRIO_LB_RD0_FLUSH_AP1	BIT(9)
206 #define V3_FIFO_PRIO_LB_RD0_FLUSH_ANY	(BIT(8)|BIT(9))
207 #define V3_FIFO_PRIO_PCI		BIT(4)
208 #define V3_FIFO_PRIO_PCI_RD1_FLUSH_EOB	BIT(2)
209 #define V3_FIFO_PRIO_PCI_RD1_FLUSH_AP1	BIT(3)
210 #define V3_FIFO_PRIO_PCI_RD1_FLUSH_ANY	(BIT(2)|BIT(3))
211 #define V3_FIFO_PRIO_PCI_RD0_FLUSH_EOB	BIT(0)
212 #define V3_FIFO_PRIO_PCI_RD0_FLUSH_AP1	BIT(1)
213 #define V3_FIFO_PRIO_PCI_RD0_FLUSH_ANY	(BIT(0)|BIT(1))
214 
215 /* Local bus configuration bits */
216 #define V3_LB_CFG_LB_TO_64_CYCLES	0x0000
217 #define V3_LB_CFG_LB_TO_256_CYCLES	BIT(13)
218 #define V3_LB_CFG_LB_TO_512_CYCLES	BIT(14)
219 #define V3_LB_CFG_LB_TO_1024_CYCLES	(BIT(13)|BIT(14))
220 #define V3_LB_CFG_LB_RST		BIT(12)
221 #define V3_LB_CFG_LB_PPC_RDY		BIT(11)
222 #define V3_LB_CFG_LB_LB_INT		BIT(10)
223 #define V3_LB_CFG_LB_ERR_EN		BIT(9)
224 #define V3_LB_CFG_LB_RDY_EN		BIT(8)
225 #define V3_LB_CFG_LB_BE_IMODE		BIT(7)
226 #define V3_LB_CFG_LB_BE_OMODE		BIT(6)
227 #define V3_LB_CFG_LB_ENDIAN		BIT(5)
228 #define V3_LB_CFG_LB_PARK_EN		BIT(4)
229 #define V3_LB_CFG_LB_FBB_DIS		BIT(2)
230 
231 /* ARM Integrator-specific extended control registers */
232 #define INTEGRATOR_SC_PCI_OFFSET	0x18
233 #define INTEGRATOR_SC_PCI_ENABLE	BIT(0)
234 #define INTEGRATOR_SC_PCI_INTCLR	BIT(1)
235 #define INTEGRATOR_SC_LBFADDR_OFFSET	0x20
236 #define INTEGRATOR_SC_LBFCODE_OFFSET	0x24
237 
238 struct v3_pci {
239 	struct device *dev;
240 	void __iomem *base;
241 	void __iomem *config_base;
242 	struct pci_bus *bus;
243 	u32 config_mem;
244 	u32 non_pre_mem;
245 	u32 pre_mem;
246 	phys_addr_t non_pre_bus_addr;
247 	phys_addr_t pre_bus_addr;
248 	struct regmap *map;
249 };
250 
251 /*
252  * The V3 PCI interface chip in Integrator provides several windows from
253  * local bus memory into the PCI memory areas. Unfortunately, there
254  * are not really enough windows for our usage, therefore we reuse
255  * one of the windows for access to PCI configuration space. On the
256  * Integrator/AP, the memory map is as follows:
257  *
258  * Local Bus Memory         Usage
259  *
260  * 40000000 - 4FFFFFFF      PCI memory.  256M non-prefetchable
261  * 50000000 - 5FFFFFFF      PCI memory.  256M prefetchable
262  * 60000000 - 60FFFFFF      PCI IO.  16M
263  * 61000000 - 61FFFFFF      PCI Configuration. 16M
264  *
265  * There are three V3 windows, each described by a pair of V3 registers.
266  * These are LB_BASE0/LB_MAP0, LB_BASE1/LB_MAP1 and LB_BASE2/LB_MAP2.
267  * Base0 and Base1 can be used for any type of PCI memory access.   Base2
268  * can be used either for PCI I/O or for I20 accesses.  By default, uHAL
269  * uses this only for PCI IO space.
270  *
271  * Normally these spaces are mapped using the following base registers:
272  *
273  * Usage Local Bus Memory         Base/Map registers used
274  *
275  * Mem   40000000 - 4FFFFFFF      LB_BASE0/LB_MAP0
276  * Mem   50000000 - 5FFFFFFF      LB_BASE1/LB_MAP1
277  * IO    60000000 - 60FFFFFF      LB_BASE2/LB_MAP2
278  * Cfg   61000000 - 61FFFFFF
279  *
280  * This means that I20 and PCI configuration space accesses will fail.
281  * When PCI configuration accesses are needed (via the uHAL PCI
282  * configuration space primitives) we must remap the spaces as follows:
283  *
284  * Usage Local Bus Memory         Base/Map registers used
285  *
286  * Mem   40000000 - 4FFFFFFF      LB_BASE0/LB_MAP0
287  * Mem   50000000 - 5FFFFFFF      LB_BASE0/LB_MAP0
288  * IO    60000000 - 60FFFFFF      LB_BASE2/LB_MAP2
289  * Cfg   61000000 - 61FFFFFF      LB_BASE1/LB_MAP1
290  *
291  * To make this work, the code depends on overlapping windows working.
292  * The V3 chip translates an address by checking its range within
293  * each of the BASE/MAP pairs in turn (in ascending register number
294  * order).  It will use the first matching pair.   So, for example,
295  * if the same address is mapped by both LB_BASE0/LB_MAP0 and
296  * LB_BASE1/LB_MAP1, the V3 will use the translation from
297  * LB_BASE0/LB_MAP0.
298  *
299  * To allow PCI Configuration space access, the code enlarges the
300  * window mapped by LB_BASE0/LB_MAP0 from 256M to 512M.  This occludes
301  * the windows currently mapped by LB_BASE1/LB_MAP1 so that it can
302  * be remapped for use by configuration cycles.
303  *
304  * At the end of the PCI Configuration space accesses,
305  * LB_BASE1/LB_MAP1 is reset to map PCI Memory.  Finally the window
306  * mapped by LB_BASE0/LB_MAP0 is reduced in size from 512M to 256M to
307  * reveal the now restored LB_BASE1/LB_MAP1 window.
308  *
309  * NOTE: We do not set up I2O mapping.  I suspect that this is only
310  * for an intelligent (target) device.  Using I2O disables most of
311  * the mappings into PCI memory.
312  */
313 static void __iomem *v3_map_bus(struct pci_bus *bus,
314 				unsigned int devfn, int offset)
315 {
316 	struct v3_pci *v3 = bus->sysdata;
317 	unsigned int address, mapaddress, busnr;
318 
319 	busnr = bus->number;
320 	if (busnr == 0) {
321 		int slot = PCI_SLOT(devfn);
322 
323 		/*
324 		 * local bus segment so need a type 0 config cycle
325 		 *
326 		 * build the PCI configuration "address" with one-hot in
327 		 * A31-A11
328 		 *
329 		 * mapaddress:
330 		 *  3:1 = config cycle (101)
331 		 *  0   = PCI A1 & A0 are 0 (0)
332 		 */
333 		address = PCI_FUNC(devfn) << 8;
334 		mapaddress = V3_LB_MAP_TYPE_CONFIG;
335 
336 		if (slot > 12)
337 			/*
338 			 * high order bits are handled by the MAP register
339 			 */
340 			mapaddress |= BIT(slot - 5);
341 		else
342 			/*
343 			 * low order bits handled directly in the address
344 			 */
345 			address |= BIT(slot + 11);
346 	} else {
347 		/*
348 		 * not the local bus segment so need a type 1 config cycle
349 		 *
350 		 * address:
351 		 *  23:16 = bus number
352 		 *  15:11 = slot number (7:3 of devfn)
353 		 *  10:8  = func number (2:0 of devfn)
354 		 *
355 		 * mapaddress:
356 		 *  3:1 = config cycle (101)
357 		 *  0   = PCI A1 & A0 from host bus (1)
358 		 */
359 		mapaddress = V3_LB_MAP_TYPE_CONFIG | V3_LB_MAP_AD_LOW_EN;
360 		address = (busnr << 16) | (devfn << 8);
361 	}
362 
363 	/*
364 	 * Set up base0 to see all 512Mbytes of memory space (not
365 	 * prefetchable), this frees up base1 for re-use by
366 	 * configuration memory
367 	 */
368 	writel(v3_addr_to_lb_base(v3->non_pre_mem) |
369 	       V3_LB_BASE_ADR_SIZE_512MB | V3_LB_BASE_ENABLE,
370 	       v3->base + V3_LB_BASE0);
371 
372 	/*
373 	 * Set up base1/map1 to point into configuration space.
374 	 * The config mem is always 16MB.
375 	 */
376 	writel(v3_addr_to_lb_base(v3->config_mem) |
377 	       V3_LB_BASE_ADR_SIZE_16MB | V3_LB_BASE_ENABLE,
378 	       v3->base + V3_LB_BASE1);
379 	writew(mapaddress, v3->base + V3_LB_MAP1);
380 
381 	return v3->config_base + address + offset;
382 }
383 
384 static void v3_unmap_bus(struct v3_pci *v3)
385 {
386 	/*
387 	 * Reassign base1 for use by prefetchable PCI memory
388 	 */
389 	writel(v3_addr_to_lb_base(v3->pre_mem) |
390 	       V3_LB_BASE_ADR_SIZE_256MB | V3_LB_BASE_PREFETCH |
391 	       V3_LB_BASE_ENABLE,
392 	       v3->base + V3_LB_BASE1);
393 	writew(v3_addr_to_lb_map(v3->pre_bus_addr) |
394 	       V3_LB_MAP_TYPE_MEM, /* was V3_LB_MAP_TYPE_MEM_MULTIPLE */
395 	       v3->base + V3_LB_MAP1);
396 
397 	/*
398 	 * And shrink base0 back to a 256M window (NOTE: MAP0 already correct)
399 	 */
400 	writel(v3_addr_to_lb_base(v3->non_pre_mem) |
401 	       V3_LB_BASE_ADR_SIZE_256MB | V3_LB_BASE_ENABLE,
402 	       v3->base + V3_LB_BASE0);
403 }
404 
405 static int v3_pci_read_config(struct pci_bus *bus, unsigned int fn,
406 			      int config, int size, u32 *value)
407 {
408 	struct v3_pci *v3 = bus->sysdata;
409 	int ret;
410 
411 	dev_dbg(&bus->dev,
412 		"[read]  slt: %.2d, fnc: %d, cnf: 0x%.2X, val (%d bytes): 0x%.8X\n",
413 		PCI_SLOT(fn), PCI_FUNC(fn), config, size, *value);
414 	ret = pci_generic_config_read(bus, fn, config, size, value);
415 	v3_unmap_bus(v3);
416 	return ret;
417 }
418 
419 static int v3_pci_write_config(struct pci_bus *bus, unsigned int fn,
420 				    int config, int size, u32 value)
421 {
422 	struct v3_pci *v3 = bus->sysdata;
423 	int ret;
424 
425 	dev_dbg(&bus->dev,
426 		"[write] slt: %.2d, fnc: %d, cnf: 0x%.2X, val (%d bytes): 0x%.8X\n",
427 		PCI_SLOT(fn), PCI_FUNC(fn), config, size, value);
428 	ret = pci_generic_config_write(bus, fn, config, size, value);
429 	v3_unmap_bus(v3);
430 	return ret;
431 }
432 
433 static struct pci_ops v3_pci_ops = {
434 	.map_bus = v3_map_bus,
435 	.read = v3_pci_read_config,
436 	.write = v3_pci_write_config,
437 };
438 
439 static irqreturn_t v3_irq(int irq, void *data)
440 {
441 	struct v3_pci *v3 = data;
442 	struct device *dev = v3->dev;
443 	u32 status;
444 
445 	status = readw(v3->base + V3_PCI_STAT);
446 	if (status & V3_PCI_STAT_PAR_ERR)
447 		dev_err(dev, "parity error interrupt\n");
448 	if (status & V3_PCI_STAT_SYS_ERR)
449 		dev_err(dev, "system error interrupt\n");
450 	if (status & V3_PCI_STAT_M_ABORT_ERR)
451 		dev_err(dev, "master abort error interrupt\n");
452 	if (status & V3_PCI_STAT_T_ABORT_ERR)
453 		dev_err(dev, "target abort error interrupt\n");
454 	writew(status, v3->base + V3_PCI_STAT);
455 
456 	status = readb(v3->base + V3_LB_ISTAT);
457 	if (status & V3_LB_ISTAT_MAILBOX)
458 		dev_info(dev, "PCI mailbox interrupt\n");
459 	if (status & V3_LB_ISTAT_PCI_RD)
460 		dev_err(dev, "PCI target LB->PCI READ abort interrupt\n");
461 	if (status & V3_LB_ISTAT_PCI_WR)
462 		dev_err(dev, "PCI target LB->PCI WRITE abort interrupt\n");
463 	if (status &  V3_LB_ISTAT_PCI_INT)
464 		dev_info(dev, "PCI pin interrupt\n");
465 	if (status & V3_LB_ISTAT_PCI_PERR)
466 		dev_err(dev, "PCI parity error interrupt\n");
467 	if (status & V3_LB_ISTAT_I2O_QWR)
468 		dev_info(dev, "I2O inbound post queue interrupt\n");
469 	if (status & V3_LB_ISTAT_DMA1)
470 		dev_info(dev, "DMA channel 1 interrupt\n");
471 	if (status & V3_LB_ISTAT_DMA0)
472 		dev_info(dev, "DMA channel 0 interrupt\n");
473 	/* Clear all possible interrupts on the local bus */
474 	writeb(0, v3->base + V3_LB_ISTAT);
475 	if (v3->map)
476 		regmap_write(v3->map, INTEGRATOR_SC_PCI_OFFSET,
477 			     INTEGRATOR_SC_PCI_ENABLE |
478 			     INTEGRATOR_SC_PCI_INTCLR);
479 
480 	return IRQ_HANDLED;
481 }
482 
483 static int v3_integrator_init(struct v3_pci *v3)
484 {
485 	unsigned int val;
486 
487 	v3->map =
488 		syscon_regmap_lookup_by_compatible("arm,integrator-ap-syscon");
489 	if (IS_ERR(v3->map)) {
490 		dev_err(v3->dev, "no syscon\n");
491 		return -ENODEV;
492 	}
493 
494 	regmap_read(v3->map, INTEGRATOR_SC_PCI_OFFSET, &val);
495 	/* Take the PCI bridge out of reset, clear IRQs */
496 	regmap_write(v3->map, INTEGRATOR_SC_PCI_OFFSET,
497 		     INTEGRATOR_SC_PCI_ENABLE |
498 		     INTEGRATOR_SC_PCI_INTCLR);
499 
500 	if (!(val & INTEGRATOR_SC_PCI_ENABLE)) {
501 		/* If we were in reset we need to sleep a bit */
502 		msleep(230);
503 
504 		/* Set the physical base for the controller itself */
505 		writel(0x6200, v3->base + V3_LB_IO_BASE);
506 
507 		/* Wait for the mailbox to settle after reset */
508 		do {
509 			writeb(0xaa, v3->base + V3_MAIL_DATA);
510 			writeb(0x55, v3->base + V3_MAIL_DATA + 4);
511 		} while (readb(v3->base + V3_MAIL_DATA) != 0xaa &&
512 			 readb(v3->base + V3_MAIL_DATA) != 0x55);
513 	}
514 
515 	dev_info(v3->dev, "initialized PCI V3 Integrator/AP integration\n");
516 
517 	return 0;
518 }
519 
520 static int v3_pci_setup_resource(struct v3_pci *v3,
521 				 struct pci_host_bridge *host,
522 				 struct resource_entry *win)
523 {
524 	struct device *dev = v3->dev;
525 	struct resource *mem;
526 	struct resource *io;
527 
528 	switch (resource_type(win->res)) {
529 	case IORESOURCE_IO:
530 		io = win->res;
531 
532 		/* Setup window 2 - PCI I/O */
533 		writel(v3_addr_to_lb_base2(pci_pio_to_address(io->start)) |
534 		       V3_LB_BASE2_ENABLE,
535 		       v3->base + V3_LB_BASE2);
536 		writew(v3_addr_to_lb_map2(io->start - win->offset),
537 		       v3->base + V3_LB_MAP2);
538 		break;
539 	case IORESOURCE_MEM:
540 		mem = win->res;
541 		if (mem->flags & IORESOURCE_PREFETCH) {
542 			mem->name = "V3 PCI PRE-MEM";
543 			v3->pre_mem = mem->start;
544 			v3->pre_bus_addr = mem->start - win->offset;
545 			dev_dbg(dev, "PREFETCHABLE MEM window %pR, bus addr %pap\n",
546 				mem, &v3->pre_bus_addr);
547 			if (resource_size(mem) != SZ_256M) {
548 				dev_err(dev, "prefetchable memory range is not 256MB\n");
549 				return -EINVAL;
550 			}
551 			if (v3->non_pre_mem &&
552 			    (mem->start != v3->non_pre_mem + SZ_256M)) {
553 				dev_err(dev,
554 					"prefetchable memory is not adjacent to non-prefetchable memory\n");
555 				return -EINVAL;
556 			}
557 			/* Setup window 1 - PCI prefetchable memory */
558 			writel(v3_addr_to_lb_base(v3->pre_mem) |
559 			       V3_LB_BASE_ADR_SIZE_256MB |
560 			       V3_LB_BASE_PREFETCH |
561 			       V3_LB_BASE_ENABLE,
562 			       v3->base + V3_LB_BASE1);
563 			writew(v3_addr_to_lb_map(v3->pre_bus_addr) |
564 			       V3_LB_MAP_TYPE_MEM, /* Was V3_LB_MAP_TYPE_MEM_MULTIPLE */
565 			       v3->base + V3_LB_MAP1);
566 		} else {
567 			mem->name = "V3 PCI NON-PRE-MEM";
568 			v3->non_pre_mem = mem->start;
569 			v3->non_pre_bus_addr = mem->start - win->offset;
570 			dev_dbg(dev, "NON-PREFETCHABLE MEM window %pR, bus addr %pap\n",
571 				mem, &v3->non_pre_bus_addr);
572 			if (resource_size(mem) != SZ_256M) {
573 				dev_err(dev,
574 					"non-prefetchable memory range is not 256MB\n");
575 				return -EINVAL;
576 			}
577 			/* Setup window 0 - PCI non-prefetchable memory */
578 			writel(v3_addr_to_lb_base(v3->non_pre_mem) |
579 			       V3_LB_BASE_ADR_SIZE_256MB |
580 			       V3_LB_BASE_ENABLE,
581 			       v3->base + V3_LB_BASE0);
582 			writew(v3_addr_to_lb_map(v3->non_pre_bus_addr) |
583 			       V3_LB_MAP_TYPE_MEM,
584 			       v3->base + V3_LB_MAP0);
585 		}
586 		break;
587 	case IORESOURCE_BUS:
588 		dev_dbg(dev, "BUS %pR\n", win->res);
589 		host->busnr = win->res->start;
590 		break;
591 	default:
592 		dev_info(dev, "Unknown resource type %lu\n",
593 			 resource_type(win->res));
594 		break;
595 	}
596 
597 	return 0;
598 }
599 
600 static int v3_get_dma_range_config(struct v3_pci *v3,
601 				   struct resource_entry *entry,
602 				   u32 *pci_base, u32 *pci_map)
603 {
604 	struct device *dev = v3->dev;
605 	u64 cpu_addr = entry->res->start;
606 	u64 cpu_end = entry->res->end;
607 	u64 pci_end = cpu_end - entry->offset;
608 	u64 pci_addr = entry->res->start - entry->offset;
609 	u32 val;
610 
611 	if (pci_addr & ~V3_PCI_BASE_M_ADR_BASE) {
612 		dev_err(dev, "illegal range, only PCI bits 31..20 allowed\n");
613 		return -EINVAL;
614 	}
615 	val = ((u32)pci_addr) & V3_PCI_BASE_M_ADR_BASE;
616 	*pci_base = val;
617 
618 	if (cpu_addr & ~V3_PCI_MAP_M_MAP_ADR) {
619 		dev_err(dev, "illegal range, only CPU bits 31..20 allowed\n");
620 		return -EINVAL;
621 	}
622 	val = ((u32)cpu_addr) & V3_PCI_MAP_M_MAP_ADR;
623 
624 	switch (resource_size(entry->res)) {
625 	case SZ_1M:
626 		val |= V3_LB_BASE_ADR_SIZE_1MB;
627 		break;
628 	case SZ_2M:
629 		val |= V3_LB_BASE_ADR_SIZE_2MB;
630 		break;
631 	case SZ_4M:
632 		val |= V3_LB_BASE_ADR_SIZE_4MB;
633 		break;
634 	case SZ_8M:
635 		val |= V3_LB_BASE_ADR_SIZE_8MB;
636 		break;
637 	case SZ_16M:
638 		val |= V3_LB_BASE_ADR_SIZE_16MB;
639 		break;
640 	case SZ_32M:
641 		val |= V3_LB_BASE_ADR_SIZE_32MB;
642 		break;
643 	case SZ_64M:
644 		val |= V3_LB_BASE_ADR_SIZE_64MB;
645 		break;
646 	case SZ_128M:
647 		val |= V3_LB_BASE_ADR_SIZE_128MB;
648 		break;
649 	case SZ_256M:
650 		val |= V3_LB_BASE_ADR_SIZE_256MB;
651 		break;
652 	case SZ_512M:
653 		val |= V3_LB_BASE_ADR_SIZE_512MB;
654 		break;
655 	case SZ_1G:
656 		val |= V3_LB_BASE_ADR_SIZE_1GB;
657 		break;
658 	case SZ_2G:
659 		val |= V3_LB_BASE_ADR_SIZE_2GB;
660 		break;
661 	default:
662 		dev_err(v3->dev, "illegal dma memory chunk size\n");
663 		return -EINVAL;
664 		break;
665 	}
666 	val |= V3_PCI_MAP_M_REG_EN | V3_PCI_MAP_M_ENABLE;
667 	*pci_map = val;
668 
669 	dev_dbg(dev,
670 		"DMA MEM CPU: 0x%016llx -> 0x%016llx => "
671 		"PCI: 0x%016llx -> 0x%016llx base %08x map %08x\n",
672 		cpu_addr, cpu_end,
673 		pci_addr, pci_end,
674 		*pci_base, *pci_map);
675 
676 	return 0;
677 }
678 
679 static int v3_pci_parse_map_dma_ranges(struct v3_pci *v3,
680 				       struct device_node *np)
681 {
682 	struct pci_host_bridge *bridge = pci_host_bridge_from_priv(v3);
683 	struct device *dev = v3->dev;
684 	struct resource_entry *entry;
685 	int i = 0;
686 
687 	resource_list_for_each_entry(entry, &bridge->dma_ranges) {
688 		int ret;
689 		u32 pci_base, pci_map;
690 
691 		ret = v3_get_dma_range_config(v3, entry, &pci_base, &pci_map);
692 		if (ret)
693 			return ret;
694 
695 		if (i == 0) {
696 			writel(pci_base, v3->base + V3_PCI_BASE0);
697 			writel(pci_map, v3->base + V3_PCI_MAP0);
698 		} else if (i == 1) {
699 			writel(pci_base, v3->base + V3_PCI_BASE1);
700 			writel(pci_map, v3->base + V3_PCI_MAP1);
701 		} else {
702 			dev_err(dev, "too many ranges, only two supported\n");
703 			dev_err(dev, "range %d ignored\n", i);
704 		}
705 		i++;
706 	}
707 	return 0;
708 }
709 
710 static int v3_pci_probe(struct platform_device *pdev)
711 {
712 	struct device *dev = &pdev->dev;
713 	struct device_node *np = dev->of_node;
714 	struct resource *regs;
715 	struct resource_entry *win;
716 	struct v3_pci *v3;
717 	struct pci_host_bridge *host;
718 	struct clk *clk;
719 	u16 val;
720 	int irq;
721 	int ret;
722 
723 	host = pci_alloc_host_bridge(sizeof(*v3));
724 	if (!host)
725 		return -ENOMEM;
726 
727 	host->dev.parent = dev;
728 	host->ops = &v3_pci_ops;
729 	host->busnr = 0;
730 	host->msi = NULL;
731 	host->map_irq = of_irq_parse_and_map_pci;
732 	host->swizzle_irq = pci_common_swizzle;
733 	v3 = pci_host_bridge_priv(host);
734 	host->sysdata = v3;
735 	v3->dev = dev;
736 
737 	/* Get and enable host clock */
738 	clk = devm_clk_get(dev, NULL);
739 	if (IS_ERR(clk)) {
740 		dev_err(dev, "clock not found\n");
741 		return PTR_ERR(clk);
742 	}
743 	ret = clk_prepare_enable(clk);
744 	if (ret) {
745 		dev_err(dev, "unable to enable clock\n");
746 		return ret;
747 	}
748 
749 	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
750 	v3->base = devm_ioremap_resource(dev, regs);
751 	if (IS_ERR(v3->base))
752 		return PTR_ERR(v3->base);
753 	/*
754 	 * The hardware has a register with the physical base address
755 	 * of the V3 controller itself, verify that this is the same
756 	 * as the physical memory we've remapped it from.
757 	 */
758 	if (readl(v3->base + V3_LB_IO_BASE) != (regs->start >> 16))
759 		dev_err(dev, "V3_LB_IO_BASE = %08x but device is @%pR\n",
760 			readl(v3->base + V3_LB_IO_BASE), regs);
761 
762 	/* Configuration space is 16MB directly mapped */
763 	regs = platform_get_resource(pdev, IORESOURCE_MEM, 1);
764 	if (resource_size(regs) != SZ_16M) {
765 		dev_err(dev, "config mem is not 16MB!\n");
766 		return -EINVAL;
767 	}
768 	v3->config_mem = regs->start;
769 	v3->config_base = devm_ioremap_resource(dev, regs);
770 	if (IS_ERR(v3->config_base))
771 		return PTR_ERR(v3->config_base);
772 
773 	ret = pci_parse_request_of_pci_ranges(dev, &host->windows,
774 					      &host->dma_ranges, NULL);
775 	if (ret)
776 		return ret;
777 
778 	/* Get and request error IRQ resource */
779 	irq = platform_get_irq(pdev, 0);
780 	if (irq <= 0) {
781 		dev_err(dev, "unable to obtain PCIv3 error IRQ\n");
782 		return -ENODEV;
783 	}
784 	ret = devm_request_irq(dev, irq, v3_irq, 0,
785 			"PCIv3 error", v3);
786 	if (ret < 0) {
787 		dev_err(dev,
788 			"unable to request PCIv3 error IRQ %d (%d)\n",
789 			irq, ret);
790 		return ret;
791 	}
792 
793 	/*
794 	 * Unlock V3 registers, but only if they were previously locked.
795 	 */
796 	if (readw(v3->base + V3_SYSTEM) & V3_SYSTEM_M_LOCK)
797 		writew(V3_SYSTEM_UNLOCK, v3->base + V3_SYSTEM);
798 
799 	/* Disable all slave access while we set up the windows */
800 	val = readw(v3->base + V3_PCI_CMD);
801 	val &= ~(PCI_COMMAND_IO | PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER);
802 	writew(val, v3->base + V3_PCI_CMD);
803 
804 	/* Put the PCI bus into reset */
805 	val = readw(v3->base + V3_SYSTEM);
806 	val &= ~V3_SYSTEM_M_RST_OUT;
807 	writew(val, v3->base + V3_SYSTEM);
808 
809 	/* Retry until we're ready */
810 	val = readw(v3->base + V3_PCI_CFG);
811 	val |= V3_PCI_CFG_M_RETRY_EN;
812 	writew(val, v3->base + V3_PCI_CFG);
813 
814 	/* Set up the local bus protocol */
815 	val = readw(v3->base + V3_LB_CFG);
816 	val |= V3_LB_CFG_LB_BE_IMODE; /* Byte enable input */
817 	val |= V3_LB_CFG_LB_BE_OMODE; /* Byte enable output */
818 	val &= ~V3_LB_CFG_LB_ENDIAN; /* Little endian */
819 	val &= ~V3_LB_CFG_LB_PPC_RDY; /* TODO: when using on PPC403Gx, set to 1 */
820 	writew(val, v3->base + V3_LB_CFG);
821 
822 	/* Enable the PCI bus master */
823 	val = readw(v3->base + V3_PCI_CMD);
824 	val |= PCI_COMMAND_MASTER;
825 	writew(val, v3->base + V3_PCI_CMD);
826 
827 	/* Get the I/O and memory ranges from DT */
828 	resource_list_for_each_entry(win, &host->windows) {
829 		ret = v3_pci_setup_resource(v3, host, win);
830 		if (ret) {
831 			dev_err(dev, "error setting up resources\n");
832 			return ret;
833 		}
834 	}
835 	ret = v3_pci_parse_map_dma_ranges(v3, np);
836 	if (ret)
837 		return ret;
838 
839 	/*
840 	 * Disable PCI to host IO cycles, enable I/O buffers @3.3V,
841 	 * set AD_LOW0 to 1 if one of the LB_MAP registers choose
842 	 * to use this (should be unused).
843 	 */
844 	writel(0x00000000, v3->base + V3_PCI_IO_BASE);
845 	val = V3_PCI_CFG_M_IO_REG_DIS | V3_PCI_CFG_M_IO_DIS |
846 		V3_PCI_CFG_M_EN3V | V3_PCI_CFG_M_AD_LOW0;
847 	/*
848 	 * DMA read and write from PCI bus commands types
849 	 */
850 	val |=  V3_PCI_CFG_TYPE_DEFAULT << V3_PCI_CFG_M_RTYPE_SHIFT;
851 	val |=  V3_PCI_CFG_TYPE_DEFAULT << V3_PCI_CFG_M_WTYPE_SHIFT;
852 	writew(val, v3->base + V3_PCI_CFG);
853 
854 	/*
855 	 * Set the V3 FIFO such that writes have higher priority than
856 	 * reads, and local bus write causes local bus read fifo flush
857 	 * on aperture 1. Same for PCI.
858 	 */
859 	writew(V3_FIFO_PRIO_LB_RD1_FLUSH_AP1 |
860 	       V3_FIFO_PRIO_LB_RD0_FLUSH_AP1 |
861 	       V3_FIFO_PRIO_PCI_RD1_FLUSH_AP1 |
862 	       V3_FIFO_PRIO_PCI_RD0_FLUSH_AP1,
863 	       v3->base + V3_FIFO_PRIORITY);
864 
865 
866 	/*
867 	 * Clear any error interrupts, and enable parity and write error
868 	 * interrupts
869 	 */
870 	writeb(0, v3->base + V3_LB_ISTAT);
871 	val = readw(v3->base + V3_LB_CFG);
872 	val |= V3_LB_CFG_LB_LB_INT;
873 	writew(val, v3->base + V3_LB_CFG);
874 	writeb(V3_LB_ISTAT_PCI_WR | V3_LB_ISTAT_PCI_PERR,
875 	       v3->base + V3_LB_IMASK);
876 
877 	/* Special Integrator initialization */
878 	if (of_device_is_compatible(np, "arm,integrator-ap-pci")) {
879 		ret = v3_integrator_init(v3);
880 		if (ret)
881 			return ret;
882 	}
883 
884 	/* Post-init: enable PCI memory and invalidate (master already on) */
885 	val = readw(v3->base + V3_PCI_CMD);
886 	val |= PCI_COMMAND_MEMORY | PCI_COMMAND_INVALIDATE;
887 	writew(val, v3->base + V3_PCI_CMD);
888 
889 	/* Clear pending interrupts */
890 	writeb(0, v3->base + V3_LB_ISTAT);
891 	/* Read or write errors and parity errors cause interrupts */
892 	writeb(V3_LB_ISTAT_PCI_RD | V3_LB_ISTAT_PCI_WR | V3_LB_ISTAT_PCI_PERR,
893 	       v3->base + V3_LB_IMASK);
894 
895 	/* Take the PCI bus out of reset so devices can initialize */
896 	val = readw(v3->base + V3_SYSTEM);
897 	val |= V3_SYSTEM_M_RST_OUT;
898 	writew(val, v3->base + V3_SYSTEM);
899 
900 	/*
901 	 * Re-lock the system register.
902 	 */
903 	val = readw(v3->base + V3_SYSTEM);
904 	val |= V3_SYSTEM_M_LOCK;
905 	writew(val, v3->base + V3_SYSTEM);
906 
907 	ret = pci_scan_root_bus_bridge(host);
908 	if (ret) {
909 		dev_err(dev, "failed to register host: %d\n", ret);
910 		return ret;
911 	}
912 	v3->bus = host->bus;
913 
914 	pci_bus_assign_resources(v3->bus);
915 	pci_bus_add_devices(v3->bus);
916 
917 	return 0;
918 }
919 
920 static const struct of_device_id v3_pci_of_match[] = {
921 	{
922 		.compatible = "v3,v360epc-pci",
923 	},
924 	{},
925 };
926 
927 static struct platform_driver v3_pci_driver = {
928 	.driver = {
929 		.name = "pci-v3-semi",
930 		.of_match_table = of_match_ptr(v3_pci_of_match),
931 		.suppress_bind_attrs = true,
932 	},
933 	.probe  = v3_pci_probe,
934 };
935 builtin_platform_driver(v3_pci_driver);
936