1 /*
2  * arch/arm/plat-iop/pci.c
3  *
4  * PCI support for the Intel IOP32X and IOP33X processors
5  *
6  * Author: Rory Bolt <rorybolt@pacbell.net>
7  * Copyright (C) 2002 Rory Bolt
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License version 2 as
11  * published by the Free Software Foundation.
12  */
13 
14 #include <linux/kernel.h>
15 #include <linux/pci.h>
16 #include <linux/slab.h>
17 #include <linux/mm.h>
18 #include <linux/init.h>
19 #include <linux/ioport.h>
20 #include <linux/io.h>
21 #include <asm/irq.h>
22 #include <asm/signal.h>
23 #include <mach/hardware.h>
24 #include <asm/mach/pci.h>
25 #include <asm/hardware/iop3xx.h>
26 
27 // #define DEBUG
28 
29 #ifdef DEBUG
30 #define  DBG(x...) printk(x)
31 #else
32 #define  DBG(x...) do { } while (0)
33 #endif
34 
35 /*
36  * This routine builds either a type0 or type1 configuration command.  If the
37  * bus is on the 803xx then a type0 made, else a type1 is created.
38  */
iop3xx_cfg_address(struct pci_bus * bus,int devfn,int where)39 static u32 iop3xx_cfg_address(struct pci_bus *bus, int devfn, int where)
40 {
41 	struct pci_sys_data *sys = bus->sysdata;
42 	u32 addr;
43 
44 	if (sys->busnr == bus->number)
45 		addr = 1 << (PCI_SLOT(devfn) + 16) | (PCI_SLOT(devfn) << 11);
46 	else
47 		addr = bus->number << 16 | PCI_SLOT(devfn) << 11 | 1;
48 
49 	addr |=	PCI_FUNC(devfn) << 8 | (where & ~3);
50 
51 	return addr;
52 }
53 
54 /*
55  * This routine checks the status of the last configuration cycle.  If an error
56  * was detected it returns a 1, else it returns a 0.  The errors being checked
57  * are parity, master abort, target abort (master and target).  These types of
58  * errors occur during a config cycle where there is no device, like during
59  * the discovery stage.
60  */
iop3xx_pci_status(void)61 static int iop3xx_pci_status(void)
62 {
63 	unsigned int status;
64 	int ret = 0;
65 
66 	/*
67 	 * Check the status registers.
68 	 */
69 	status = *IOP3XX_ATUSR;
70 	if (status & 0xf900) {
71 		DBG("\t\t\tPCI: P0 - status = 0x%08x\n", status);
72 		*IOP3XX_ATUSR = status & 0xf900;
73 		ret = 1;
74 	}
75 
76 	status = *IOP3XX_ATUISR;
77 	if (status & 0x679f) {
78 		DBG("\t\t\tPCI: P1 - status = 0x%08x\n", status);
79 		*IOP3XX_ATUISR = status & 0x679f;
80 		ret = 1;
81 	}
82 
83 	return ret;
84 }
85 
86 /*
87  * Simply write the address register and read the configuration
88  * data.  Note that the 4 nops ensure that we are able to handle
89  * a delayed abort (in theory.)
90  */
iop3xx_read(unsigned long addr)91 static u32 iop3xx_read(unsigned long addr)
92 {
93 	u32 val;
94 
95 	__asm__ __volatile__(
96 		"str	%1, [%2]\n\t"
97 		"ldr	%0, [%3]\n\t"
98 		"nop\n\t"
99 		"nop\n\t"
100 		"nop\n\t"
101 		"nop\n\t"
102 		: "=r" (val)
103 		: "r" (addr), "r" (IOP3XX_OCCAR), "r" (IOP3XX_OCCDR));
104 
105 	return val;
106 }
107 
108 /*
109  * The read routines must check the error status of the last configuration
110  * cycle.  If there was an error, the routine returns all hex f's.
111  */
112 static int
iop3xx_read_config(struct pci_bus * bus,unsigned int devfn,int where,int size,u32 * value)113 iop3xx_read_config(struct pci_bus *bus, unsigned int devfn, int where,
114 		int size, u32 *value)
115 {
116 	unsigned long addr = iop3xx_cfg_address(bus, devfn, where);
117 	u32 val = iop3xx_read(addr) >> ((where & 3) * 8);
118 
119 	if (iop3xx_pci_status())
120 		val = 0xffffffff;
121 
122 	*value = val;
123 
124 	return PCIBIOS_SUCCESSFUL;
125 }
126 
127 static int
iop3xx_write_config(struct pci_bus * bus,unsigned int devfn,int where,int size,u32 value)128 iop3xx_write_config(struct pci_bus *bus, unsigned int devfn, int where,
129 		int size, u32 value)
130 {
131 	unsigned long addr = iop3xx_cfg_address(bus, devfn, where);
132 	u32 val;
133 
134 	if (size != 4) {
135 		val = iop3xx_read(addr);
136 		if (iop3xx_pci_status())
137 			return PCIBIOS_SUCCESSFUL;
138 
139 		where = (where & 3) * 8;
140 
141 		if (size == 1)
142 			val &= ~(0xff << where);
143 		else
144 			val &= ~(0xffff << where);
145 
146 		*IOP3XX_OCCDR = val | value << where;
147 	} else {
148 		asm volatile(
149 			"str	%1, [%2]\n\t"
150 			"str	%0, [%3]\n\t"
151 			"nop\n\t"
152 			"nop\n\t"
153 			"nop\n\t"
154 			"nop\n\t"
155 			:
156 			: "r" (value), "r" (addr),
157 			  "r" (IOP3XX_OCCAR), "r" (IOP3XX_OCCDR));
158 	}
159 
160 	return PCIBIOS_SUCCESSFUL;
161 }
162 
163 static struct pci_ops iop3xx_ops = {
164 	.read	= iop3xx_read_config,
165 	.write	= iop3xx_write_config,
166 };
167 
168 /*
169  * When a PCI device does not exist during config cycles, the 80200 gets a
170  * bus error instead of returning 0xffffffff. This handler simply returns.
171  */
172 static int
iop3xx_pci_abort(unsigned long addr,unsigned int fsr,struct pt_regs * regs)173 iop3xx_pci_abort(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
174 {
175 	DBG("PCI abort: address = 0x%08lx fsr = 0x%03x PC = 0x%08lx LR = 0x%08lx\n",
176 		addr, fsr, regs->ARM_pc, regs->ARM_lr);
177 
178 	/*
179 	 * If it was an imprecise abort, then we need to correct the
180 	 * return address to be _after_ the instruction.
181 	 */
182 	if (fsr & (1 << 10))
183 		regs->ARM_pc += 4;
184 
185 	return 0;
186 }
187 
iop3xx_pci_setup(int nr,struct pci_sys_data * sys)188 int iop3xx_pci_setup(int nr, struct pci_sys_data *sys)
189 {
190 	struct resource *res;
191 
192 	if (nr != 0)
193 		return 0;
194 
195 	res = kzalloc(2 * sizeof(struct resource), GFP_KERNEL);
196 	if (!res)
197 		panic("PCI: unable to alloc resources");
198 
199 	res[0].start = IOP3XX_PCI_LOWER_IO_PA;
200 	res[0].end   = IOP3XX_PCI_LOWER_IO_PA + IOP3XX_PCI_IO_WINDOW_SIZE - 1;
201 	res[0].name  = "IOP3XX PCI I/O Space";
202 	res[0].flags = IORESOURCE_IO;
203 	request_resource(&ioport_resource, &res[0]);
204 
205 	res[1].start = IOP3XX_PCI_LOWER_MEM_PA;
206 	res[1].end   = IOP3XX_PCI_LOWER_MEM_PA + IOP3XX_PCI_MEM_WINDOW_SIZE - 1;
207 	res[1].name  = "IOP3XX PCI Memory Space";
208 	res[1].flags = IORESOURCE_MEM;
209 	request_resource(&iomem_resource, &res[1]);
210 
211 	/*
212 	 * Use whatever translation is already setup.
213 	 */
214 	sys->mem_offset = IOP3XX_PCI_LOWER_MEM_PA - *IOP3XX_OMWTVR0;
215 	sys->io_offset  = IOP3XX_PCI_LOWER_IO_PA - *IOP3XX_OIOWTVR;
216 
217 	pci_add_resource_offset(&sys->resources, &res[0], sys->io_offset);
218 	pci_add_resource_offset(&sys->resources, &res[1], sys->mem_offset);
219 
220 	return 1;
221 }
222 
iop3xx_pci_scan_bus(int nr,struct pci_sys_data * sys)223 struct pci_bus *iop3xx_pci_scan_bus(int nr, struct pci_sys_data *sys)
224 {
225 	return pci_scan_root_bus(NULL, sys->busnr, &iop3xx_ops, sys,
226 				 &sys->resources);
227 }
228 
iop3xx_atu_setup(void)229 void __init iop3xx_atu_setup(void)
230 {
231 	/* BAR 0 ( Disabled ) */
232 	*IOP3XX_IAUBAR0 = 0x0;
233 	*IOP3XX_IABAR0  = 0x0;
234 	*IOP3XX_IATVR0  = 0x0;
235 	*IOP3XX_IALR0   = 0x0;
236 
237 	/* BAR 1 ( Disabled ) */
238 	*IOP3XX_IAUBAR1 = 0x0;
239 	*IOP3XX_IABAR1  = 0x0;
240 	*IOP3XX_IALR1   = 0x0;
241 
242 	/* BAR 2 (1:1 mapping with Physical RAM) */
243 	/* Set limit and enable */
244 	*IOP3XX_IALR2 = ~((u32)IOP3XX_MAX_RAM_SIZE - 1) & ~0x1;
245 	*IOP3XX_IAUBAR2 = 0x0;
246 
247 	/* Align the inbound bar with the base of memory */
248 	*IOP3XX_IABAR2 = PHYS_OFFSET |
249 			       PCI_BASE_ADDRESS_MEM_TYPE_64 |
250 			       PCI_BASE_ADDRESS_MEM_PREFETCH;
251 
252 	*IOP3XX_IATVR2 = PHYS_OFFSET;
253 
254 	/* Outbound window 0 */
255 	*IOP3XX_OMWTVR0 = IOP3XX_PCI_LOWER_MEM_BA;
256 	*IOP3XX_OUMWTVR0 = 0;
257 
258 	/* Outbound window 1 */
259 	*IOP3XX_OMWTVR1 = IOP3XX_PCI_LOWER_MEM_BA +
260 			  IOP3XX_PCI_MEM_WINDOW_SIZE / 2;
261 	*IOP3XX_OUMWTVR1 = 0;
262 
263 	/* BAR 3 ( Disabled ) */
264 	*IOP3XX_IAUBAR3 = 0x0;
265 	*IOP3XX_IABAR3  = 0x0;
266 	*IOP3XX_IATVR3  = 0x0;
267 	*IOP3XX_IALR3   = 0x0;
268 
269 	/* Setup the I/O Bar
270 	 */
271 	*IOP3XX_OIOWTVR = IOP3XX_PCI_LOWER_IO_BA;
272 
273 	/* Enable inbound and outbound cycles
274 	 */
275 	*IOP3XX_ATUCMD |= PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER |
276 			       PCI_COMMAND_PARITY | PCI_COMMAND_SERR;
277 	*IOP3XX_ATUCR |= IOP3XX_ATUCR_OUT_EN;
278 }
279 
iop3xx_atu_disable(void)280 void __init iop3xx_atu_disable(void)
281 {
282 	*IOP3XX_ATUCMD = 0;
283 	*IOP3XX_ATUCR = 0;
284 
285 	/* wait for cycles to quiesce */
286 	while (*IOP3XX_PCSR & (IOP3XX_PCSR_OUT_Q_BUSY |
287 				     IOP3XX_PCSR_IN_Q_BUSY))
288 		cpu_relax();
289 
290 	/* BAR 0 ( Disabled ) */
291 	*IOP3XX_IAUBAR0 = 0x0;
292 	*IOP3XX_IABAR0  = 0x0;
293 	*IOP3XX_IATVR0  = 0x0;
294 	*IOP3XX_IALR0   = 0x0;
295 
296 	/* BAR 1 ( Disabled ) */
297 	*IOP3XX_IAUBAR1 = 0x0;
298 	*IOP3XX_IABAR1  = 0x0;
299 	*IOP3XX_IALR1   = 0x0;
300 
301 	/* BAR 2 ( Disabled ) */
302 	*IOP3XX_IAUBAR2 = 0x0;
303 	*IOP3XX_IABAR2  = 0x0;
304 	*IOP3XX_IATVR2  = 0x0;
305 	*IOP3XX_IALR2   = 0x0;
306 
307 	/* BAR 3 ( Disabled ) */
308 	*IOP3XX_IAUBAR3 = 0x0;
309 	*IOP3XX_IABAR3  = 0x0;
310 	*IOP3XX_IATVR3  = 0x0;
311 	*IOP3XX_IALR3   = 0x0;
312 
313 	/* Clear the outbound windows */
314 	*IOP3XX_OIOWTVR  = 0;
315 
316 	/* Outbound window 0 */
317 	*IOP3XX_OMWTVR0 = 0;
318 	*IOP3XX_OUMWTVR0 = 0;
319 
320 	/* Outbound window 1 */
321 	*IOP3XX_OMWTVR1 = 0;
322 	*IOP3XX_OUMWTVR1 = 0;
323 }
324 
325 /* Flag to determine whether the ATU is initialized and the PCI bus scanned */
326 int init_atu;
327 
iop3xx_get_init_atu(void)328 int iop3xx_get_init_atu(void) {
329 	/* check if default has been overridden */
330 	if (init_atu != IOP3XX_INIT_ATU_DEFAULT)
331 		return init_atu;
332 	else
333 		return IOP3XX_INIT_ATU_DISABLE;
334 }
335 
iop3xx_atu_debug(void)336 static void __init iop3xx_atu_debug(void)
337 {
338 	DBG("PCI: Intel IOP3xx PCI init.\n");
339 	DBG("PCI: Outbound memory window 0: PCI 0x%08x%08x\n",
340 		*IOP3XX_OUMWTVR0, *IOP3XX_OMWTVR0);
341 	DBG("PCI: Outbound memory window 1: PCI 0x%08x%08x\n",
342 		*IOP3XX_OUMWTVR1, *IOP3XX_OMWTVR1);
343 	DBG("PCI: Outbound IO window: PCI 0x%08x\n",
344 		*IOP3XX_OIOWTVR);
345 
346 	DBG("PCI: Inbound memory window 0: PCI 0x%08x%08x 0x%08x -> 0x%08x\n",
347 		*IOP3XX_IAUBAR0, *IOP3XX_IABAR0, *IOP3XX_IALR0, *IOP3XX_IATVR0);
348 	DBG("PCI: Inbound memory window 1: PCI 0x%08x%08x 0x%08x\n",
349 		*IOP3XX_IAUBAR1, *IOP3XX_IABAR1, *IOP3XX_IALR1);
350 	DBG("PCI: Inbound memory window 2: PCI 0x%08x%08x 0x%08x -> 0x%08x\n",
351 		*IOP3XX_IAUBAR2, *IOP3XX_IABAR2, *IOP3XX_IALR2, *IOP3XX_IATVR2);
352 	DBG("PCI: Inbound memory window 3: PCI 0x%08x%08x 0x%08x -> 0x%08x\n",
353 		*IOP3XX_IAUBAR3, *IOP3XX_IABAR3, *IOP3XX_IALR3, *IOP3XX_IATVR3);
354 
355 	DBG("PCI: Expansion ROM window: PCI 0x%08x%08x 0x%08x -> 0x%08x\n",
356 		0, *IOP3XX_ERBAR, *IOP3XX_ERLR, *IOP3XX_ERTVR);
357 
358 	DBG("ATU: IOP3XX_ATUCMD=0x%04x\n", *IOP3XX_ATUCMD);
359 	DBG("ATU: IOP3XX_ATUCR=0x%08x\n", *IOP3XX_ATUCR);
360 
361 	hook_fault_code(16+6, iop3xx_pci_abort, SIGBUS, 0, "imprecise external abort");
362 }
363 
364 /* for platforms that might be host-bus-adapters */
iop3xx_pci_preinit_cond(void)365 void __init iop3xx_pci_preinit_cond(void)
366 {
367 	if (iop3xx_get_init_atu() == IOP3XX_INIT_ATU_ENABLE) {
368 		iop3xx_atu_disable();
369 		iop3xx_atu_setup();
370 		iop3xx_atu_debug();
371 	}
372 }
373 
iop3xx_pci_preinit(void)374 void __init iop3xx_pci_preinit(void)
375 {
376 	pcibios_min_io = 0;
377 	pcibios_min_mem = 0;
378 
379 	iop3xx_atu_disable();
380 	iop3xx_atu_setup();
381 	iop3xx_atu_debug();
382 }
383 
384 /* allow init_atu to be user overridden */
iop3xx_init_atu_setup(char * str)385 static int __init iop3xx_init_atu_setup(char *str)
386 {
387 	init_atu = IOP3XX_INIT_ATU_DEFAULT;
388 	if (str) {
389 		while (*str != '\0') {
390 			switch (*str) {
391 			case 'y':
392 			case 'Y':
393 				init_atu = IOP3XX_INIT_ATU_ENABLE;
394 				break;
395 			case 'n':
396 			case 'N':
397 				init_atu = IOP3XX_INIT_ATU_DISABLE;
398 				break;
399 			case ',':
400 			case '=':
401 				break;
402 			default:
403 				printk(KERN_DEBUG "\"%s\" malformed at "
404 					    "character: \'%c\'",
405 					    __func__,
406 					    *str);
407 				*(str + 1) = '\0';
408 			}
409 			str++;
410 		}
411 	}
412 
413 	return 1;
414 }
415 
416 __setup("iop3xx_init_atu", iop3xx_init_atu_setup);
417 
418