xref: /openbmc/linux/arch/powerpc/sysdev/tsi108_pci.c (revision 22246614)
1 /*
2  * Common routines for Tundra Semiconductor TSI108 host bridge.
3  *
4  * 2004-2005 (c) Tundra Semiconductor Corp.
5  * Author: Alex Bounine (alexandreb@tundra.com)
6  * Author: Roy Zang (tie-fei.zang@freescale.com)
7  * 	   Add pci interrupt router host
8  *
9  * This program is free software; you can redistribute it and/or modify it
10  * under the terms of the GNU General Public License as published by the Free
11  * Software Foundation; either version 2 of the License, or (at your option)
12  * any later version.
13  *
14  * This program is distributed in the hope that it will be useful, but WITHOUT
15  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
16  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
17  * more details.
18  *
19  * You should have received a copy of the GNU General Public License along with
20  * this program; if not, write to the Free Software Foundation, Inc., 59
21  * Temple Place - Suite 330, Boston, MA  02111-1307, USA.
22  */
23 
24 #include <linux/kernel.h>
25 #include <linux/init.h>
26 #include <linux/pci.h>
27 #include <linux/slab.h>
28 #include <linux/irq.h>
29 #include <linux/interrupt.h>
30 
31 #include <asm/byteorder.h>
32 #include <asm/io.h>
33 #include <asm/irq.h>
34 #include <asm/uaccess.h>
35 #include <asm/machdep.h>
36 #include <asm/pci-bridge.h>
37 #include <asm/tsi108.h>
38 #include <asm/tsi108_pci.h>
39 #include <asm/tsi108_irq.h>
40 #include <asm/prom.h>
41 
42 #undef DEBUG
43 #ifdef DEBUG
44 #define DBG(x...) printk(x)
45 #else
46 #define DBG(x...)
47 #endif
48 
49 #define tsi_mk_config_addr(bus, devfunc, offset) \
50 	((((bus)<<16) | ((devfunc)<<8) | (offset & 0xfc)) + tsi108_pci_cfg_base)
51 
52 u32 tsi108_pci_cfg_base;
53 static u32 tsi108_pci_cfg_phys;
54 u32 tsi108_csr_vir_base;
55 static struct irq_host *pci_irq_host;
56 
57 extern u32 get_vir_csrbase(void);
58 extern u32 tsi108_read_reg(u32 reg_offset);
59 extern void tsi108_write_reg(u32 reg_offset, u32 val);
60 
61 int
62 tsi108_direct_write_config(struct pci_bus *bus, unsigned int devfunc,
63 			   int offset, int len, u32 val)
64 {
65 	volatile unsigned char *cfg_addr;
66 	struct pci_controller *hose = bus->sysdata;
67 
68 	if (ppc_md.pci_exclude_device)
69 		if (ppc_md.pci_exclude_device(hose, bus->number, devfunc))
70 			return PCIBIOS_DEVICE_NOT_FOUND;
71 
72 	cfg_addr = (unsigned char *)(tsi_mk_config_addr(bus->number,
73 							devfunc, offset) |
74 							(offset & 0x03));
75 
76 #ifdef DEBUG
77 	printk("PCI CFG write : ");
78 	printk("%d:0x%x:0x%x ", bus->number, devfunc, offset);
79 	printk("%d ADDR=0x%08x ", len, (uint) cfg_addr);
80 	printk("data = 0x%08x\n", val);
81 #endif
82 
83 	switch (len) {
84 	case 1:
85 		out_8((u8 *) cfg_addr, val);
86 		break;
87 	case 2:
88 		out_le16((u16 *) cfg_addr, val);
89 		break;
90 	default:
91 		out_le32((u32 *) cfg_addr, val);
92 		break;
93 	}
94 
95 	return PCIBIOS_SUCCESSFUL;
96 }
97 
98 void tsi108_clear_pci_error(u32 pci_cfg_base)
99 {
100 	u32 err_stat, err_addr, pci_stat;
101 
102 	/*
103 	 * Quietly clear PB and PCI error flags set as result
104 	 * of PCI/X configuration read requests.
105 	 */
106 
107 	/* Read PB Error Log Registers */
108 
109 	err_stat = tsi108_read_reg(TSI108_PB_OFFSET + TSI108_PB_ERRCS);
110 	err_addr = tsi108_read_reg(TSI108_PB_OFFSET + TSI108_PB_AERR);
111 
112 	if (err_stat & TSI108_PB_ERRCS_ES) {
113 		/* Clear error flag */
114 		tsi108_write_reg(TSI108_PB_OFFSET + TSI108_PB_ERRCS,
115 				 TSI108_PB_ERRCS_ES);
116 
117 		/* Clear read error reported in PB_ISR */
118 		tsi108_write_reg(TSI108_PB_OFFSET + TSI108_PB_ISR,
119 				 TSI108_PB_ISR_PBS_RD_ERR);
120 
121 		/* Clear PCI/X bus cfg errors if applicable */
122 		if ((err_addr & 0xFF000000) == pci_cfg_base) {
123 			pci_stat =
124 			    tsi108_read_reg(TSI108_PCI_OFFSET + TSI108_PCI_CSR);
125 			tsi108_write_reg(TSI108_PCI_OFFSET + TSI108_PCI_CSR,
126 					 pci_stat);
127 		}
128 	}
129 
130 	return;
131 }
132 
133 #define __tsi108_read_pci_config(x, addr, op)		\
134 	__asm__ __volatile__(				\
135 		"	"op" %0,0,%1\n"		\
136 		"1:	eieio\n"			\
137 		"2:\n"					\
138 		".section .fixup,\"ax\"\n"		\
139 		"3:	li %0,-1\n"			\
140 		"	b 2b\n"				\
141 		".section __ex_table,\"a\"\n"		\
142 		"	.align 2\n"			\
143 		"	.long 1b,3b\n"			\
144 		".text"					\
145 		: "=r"(x) : "r"(addr))
146 
147 int
148 tsi108_direct_read_config(struct pci_bus *bus, unsigned int devfn, int offset,
149 			  int len, u32 * val)
150 {
151 	volatile unsigned char *cfg_addr;
152 	struct pci_controller *hose = bus->sysdata;
153 	u32 temp;
154 
155 	if (ppc_md.pci_exclude_device)
156 		if (ppc_md.pci_exclude_device(hose, bus->number, devfn))
157 			return PCIBIOS_DEVICE_NOT_FOUND;
158 
159 	cfg_addr = (unsigned char *)(tsi_mk_config_addr(bus->number,
160 							devfn,
161 							offset) | (offset &
162 								   0x03));
163 
164 	switch (len) {
165 	case 1:
166 		__tsi108_read_pci_config(temp, cfg_addr, "lbzx");
167 		break;
168 	case 2:
169 		__tsi108_read_pci_config(temp, cfg_addr, "lhbrx");
170 		break;
171 	default:
172 		__tsi108_read_pci_config(temp, cfg_addr, "lwbrx");
173 		break;
174 	}
175 
176 	*val = temp;
177 
178 #ifdef DEBUG
179 	if ((0xFFFFFFFF != temp) && (0xFFFF != temp) && (0xFF != temp)) {
180 		printk("PCI CFG read : ");
181 		printk("%d:0x%x:0x%x ", bus->number, devfn, offset);
182 		printk("%d ADDR=0x%08x ", len, (uint) cfg_addr);
183 		printk("data = 0x%x\n", *val);
184 	}
185 #endif
186 	return PCIBIOS_SUCCESSFUL;
187 }
188 
189 void tsi108_clear_pci_cfg_error(void)
190 {
191 	tsi108_clear_pci_error(tsi108_pci_cfg_phys);
192 }
193 
194 static struct pci_ops tsi108_direct_pci_ops = {
195 	.read = tsi108_direct_read_config,
196 	.write = tsi108_direct_write_config,
197 };
198 
199 int __init tsi108_setup_pci(struct device_node *dev, u32 cfg_phys, int primary)
200 {
201 	int len;
202 	struct pci_controller *hose;
203 	struct resource rsrc;
204 	const int *bus_range;
205 	int has_address = 0;
206 
207 	/* PCI Config mapping */
208 	tsi108_pci_cfg_base = (u32)ioremap(cfg_phys, TSI108_PCI_CFG_SIZE);
209 	tsi108_pci_cfg_phys = cfg_phys;
210 	DBG("TSI_PCI: %s tsi108_pci_cfg_base=0x%x\n", __func__,
211 	    tsi108_pci_cfg_base);
212 
213 	/* Fetch host bridge registers address */
214 	has_address = (of_address_to_resource(dev, 0, &rsrc) == 0);
215 
216 	/* Get bus range if any */
217 	bus_range = of_get_property(dev, "bus-range", &len);
218 	if (bus_range == NULL || len < 2 * sizeof(int)) {
219 		printk(KERN_WARNING "Can't get bus-range for %s, assume"
220 		       " bus 0\n", dev->full_name);
221 	}
222 
223 	hose = pcibios_alloc_controller(dev);
224 
225 	if (!hose) {
226 		printk("PCI Host bridge init failed\n");
227 		return -ENOMEM;
228 	}
229 
230 	hose->first_busno = bus_range ? bus_range[0] : 0;
231 	hose->last_busno = bus_range ? bus_range[1] : 0xff;
232 
233 	(hose)->ops = &tsi108_direct_pci_ops;
234 
235 	printk(KERN_INFO "Found tsi108 PCI host bridge at 0x%08x. "
236 	       "Firmware bus number: %d->%d\n",
237 	       rsrc.start, hose->first_busno, hose->last_busno);
238 
239 	/* Interpret the "ranges" property */
240 	/* This also maps the I/O region and sets isa_io/mem_base */
241 	pci_process_bridge_OF_ranges(hose, dev, primary);
242 	return 0;
243 }
244 
245 /*
246  * Low level utility functions
247  */
248 
249 static void tsi108_pci_int_mask(u_int irq)
250 {
251 	u_int irp_cfg;
252 	int int_line = (irq - IRQ_PCI_INTAD_BASE);
253 
254 	irp_cfg = tsi108_read_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_CFG_CTL);
255 	mb();
256 	irp_cfg |= (1 << int_line);	/* INTx_DIR = output */
257 	irp_cfg &= ~(3 << (8 + (int_line * 2)));	/* INTx_TYPE = unused */
258 	tsi108_write_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_CFG_CTL, irp_cfg);
259 	mb();
260 	irp_cfg = tsi108_read_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_CFG_CTL);
261 }
262 
263 static void tsi108_pci_int_unmask(u_int irq)
264 {
265 	u_int irp_cfg;
266 	int int_line = (irq - IRQ_PCI_INTAD_BASE);
267 
268 	irp_cfg = tsi108_read_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_CFG_CTL);
269 	mb();
270 	irp_cfg &= ~(1 << int_line);
271 	irp_cfg |= (3 << (8 + (int_line * 2)));
272 	tsi108_write_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_CFG_CTL, irp_cfg);
273 	mb();
274 }
275 
276 static void init_pci_source(void)
277 {
278 	tsi108_write_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_CFG_CTL,
279 			0x0000ff00);
280 	tsi108_write_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_ENABLE,
281 			TSI108_PCI_IRP_ENABLE_P_INT);
282 	mb();
283 }
284 
285 static inline unsigned int get_pci_source(void)
286 {
287 	u_int temp = 0;
288 	int irq = -1;
289 	int i;
290 	u_int pci_irp_stat;
291 	static int mask = 0;
292 
293 	/* Read PCI/X block interrupt status register */
294 	pci_irp_stat = tsi108_read_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_STAT);
295 	mb();
296 
297 	if (pci_irp_stat & TSI108_PCI_IRP_STAT_P_INT) {
298 		/* Process Interrupt from PCI bus INTA# - INTD# lines */
299 		temp =
300 		    tsi108_read_reg(TSI108_PCI_OFFSET +
301 				    TSI108_PCI_IRP_INTAD) & 0xf;
302 		mb();
303 		for (i = 0; i < 4; i++, mask++) {
304 			if (temp & (1 << mask % 4)) {
305 				irq = IRQ_PCI_INTA + mask % 4;
306 				mask++;
307 				break;
308 			}
309 		}
310 
311 		/* Disable interrupts from PCI block */
312 		temp = tsi108_read_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_ENABLE);
313 		tsi108_write_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_ENABLE,
314 				temp & ~TSI108_PCI_IRP_ENABLE_P_INT);
315 		mb();
316 		(void)tsi108_read_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_ENABLE);
317 		mb();
318 	}
319 #ifdef DEBUG
320 	else {
321 		printk("TSI108_PIC: error in TSI108_PCI_IRP_STAT\n");
322 		pci_irp_stat =
323 		    tsi108_read_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_STAT);
324 		temp =
325 		    tsi108_read_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_INTAD);
326 		mb();
327 		printk(">> stat=0x%08x intad=0x%08x ", pci_irp_stat, temp);
328 		temp =
329 		    tsi108_read_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_CFG_CTL);
330 		mb();
331 		printk("cfg_ctl=0x%08x ", temp);
332 		temp =
333 		    tsi108_read_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_ENABLE);
334 		mb();
335 		printk("irp_enable=0x%08x\n", temp);
336 	}
337 #endif	/* end of DEBUG */
338 
339 	return irq;
340 }
341 
342 
343 /*
344  * Linux descriptor level callbacks
345  */
346 
347 static void tsi108_pci_irq_enable(u_int irq)
348 {
349 	tsi108_pci_int_unmask(irq);
350 }
351 
352 static void tsi108_pci_irq_disable(u_int irq)
353 {
354 	tsi108_pci_int_mask(irq);
355 }
356 
357 static void tsi108_pci_irq_ack(u_int irq)
358 {
359 	tsi108_pci_int_mask(irq);
360 }
361 
362 static void tsi108_pci_irq_end(u_int irq)
363 {
364 	tsi108_pci_int_unmask(irq);
365 
366 	/* Enable interrupts from PCI block */
367 	tsi108_write_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_ENABLE,
368 			 tsi108_read_reg(TSI108_PCI_OFFSET +
369 					 TSI108_PCI_IRP_ENABLE) |
370 			 TSI108_PCI_IRP_ENABLE_P_INT);
371 	mb();
372 }
373 
374 /*
375  * Interrupt controller descriptor for cascaded PCI interrupt controller.
376  */
377 
378 static struct irq_chip tsi108_pci_irq = {
379 	.typename = "tsi108_PCI_int",
380 	.mask = tsi108_pci_irq_disable,
381 	.ack = tsi108_pci_irq_ack,
382 	.end = tsi108_pci_irq_end,
383 	.unmask = tsi108_pci_irq_enable,
384 };
385 
386 static int pci_irq_host_xlate(struct irq_host *h, struct device_node *ct,
387 			    u32 *intspec, unsigned int intsize,
388 			    irq_hw_number_t *out_hwirq, unsigned int *out_flags)
389 {
390 	*out_hwirq = intspec[0];
391 	*out_flags = IRQ_TYPE_LEVEL_HIGH;
392 	return 0;
393 }
394 
395 static int pci_irq_host_map(struct irq_host *h, unsigned int virq,
396 			  irq_hw_number_t hw)
397 {	unsigned int irq;
398 	DBG("%s(%d, 0x%lx)\n", __func__, virq, hw);
399 	if ((virq >= 1) && (virq <= 4)){
400 		irq = virq + IRQ_PCI_INTAD_BASE - 1;
401 		get_irq_desc(irq)->status |= IRQ_LEVEL;
402 		set_irq_chip(irq, &tsi108_pci_irq);
403 	}
404 	return 0;
405 }
406 
407 static struct irq_host_ops pci_irq_host_ops = {
408 	.map = pci_irq_host_map,
409 	.xlate = pci_irq_host_xlate,
410 };
411 
412 /*
413  * Exported functions
414  */
415 
416 /*
417  * The Tsi108 PCI interrupts initialization routine.
418  *
419  * The INTA# - INTD# interrupts on the PCI bus are reported by the PCI block
420  * to the MPIC using single interrupt source (IRQ_TSI108_PCI). Therefore the
421  * PCI block has to be treated as a cascaded interrupt controller connected
422  * to the MPIC.
423  */
424 
425 void __init tsi108_pci_int_init(struct device_node *node)
426 {
427 	DBG("Tsi108_pci_int_init: initializing PCI interrupts\n");
428 
429 	pci_irq_host = irq_alloc_host(of_node_get(node), IRQ_HOST_MAP_LEGACY,
430 				      0, &pci_irq_host_ops, 0);
431 	if (pci_irq_host == NULL) {
432 		printk(KERN_ERR "pci_irq_host: failed to allocate irq host !\n");
433 		of_node_put(node);
434 		return;
435 	}
436 
437 	init_pci_source();
438 }
439 
440 void tsi108_irq_cascade(unsigned int irq, struct irq_desc *desc)
441 {
442 	unsigned int cascade_irq = get_pci_source();
443 	if (cascade_irq != NO_IRQ)
444 		generic_handle_irq(cascade_irq);
445 	desc->chip->eoi(irq);
446 }
447