xref: /linux/arch/powerpc/sysdev/tsi108_pci.c (revision 5e8d780d745c1619aba81fe7166c5a4b5cad2b84)
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  *
7  * This program is free software; you can redistribute it and/or modify it
8  * under the terms of the GNU General Public License as published by the Free
9  * Software Foundation; either version 2 of the License, or (at your option)
10  * any later version.
11  *
12  * This program is distributed in the hope that it will be useful, but WITHOUT
13  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
15  * more details.
16  *
17  * You should have received a copy of the GNU General Public License along with
18  * this program; if not, write to the Free Software Foundation, Inc., 59
19  * Temple Place - Suite 330, Boston, MA  02111-1307, USA.
20  */
21 
22 #include <linux/kernel.h>
23 #include <linux/init.h>
24 #include <linux/pci.h>
25 #include <linux/slab.h>
26 #include <linux/irq.h>
27 #include <linux/interrupt.h>
28 
29 
30 #include <asm/byteorder.h>
31 #include <asm/io.h>
32 #include <asm/irq.h>
33 #include <asm/uaccess.h>
34 #include <asm/machdep.h>
35 #include <asm/pci-bridge.h>
36 #include <asm/tsi108.h>
37 #include <asm/tsi108_irq.h>
38 #include <asm/prom.h>
39 
40 #undef DEBUG
41 #ifdef DEBUG
42 #define DBG(x...) printk(x)
43 #else
44 #define DBG(x...)
45 #endif
46 
47 #define tsi_mk_config_addr(bus, devfunc, offset) \
48 	((((bus)<<16) | ((devfunc)<<8) | (offset & 0xfc)) + tsi108_pci_cfg_base)
49 
50 u32 tsi108_pci_cfg_base;
51 u32 tsi108_csr_vir_base;
52 
53 extern u32 get_vir_csrbase(void);
54 extern u32 tsi108_read_reg(u32 reg_offset);
55 extern void tsi108_write_reg(u32 reg_offset, u32 val);
56 
57 int
58 tsi108_direct_write_config(struct pci_bus *bus, unsigned int devfunc,
59 			   int offset, int len, u32 val)
60 {
61 	volatile unsigned char *cfg_addr;
62 
63 	if (ppc_md.pci_exclude_device)
64 		if (ppc_md.pci_exclude_device(bus->number, devfunc))
65 			return PCIBIOS_DEVICE_NOT_FOUND;
66 
67 	cfg_addr = (unsigned char *)(tsi_mk_config_addr(bus->number,
68 							devfunc, offset) |
69 							(offset & 0x03));
70 
71 #ifdef DEBUG
72 	printk("PCI CFG write : ");
73 	printk("%d:0x%x:0x%x ", bus->number, devfunc, offset);
74 	printk("%d ADDR=0x%08x ", len, (uint) cfg_addr);
75 	printk("data = 0x%08x\n", val);
76 #endif
77 
78 	switch (len) {
79 	case 1:
80 		out_8((u8 *) cfg_addr, val);
81 		break;
82 	case 2:
83 		out_le16((u16 *) cfg_addr, val);
84 		break;
85 	default:
86 		out_le32((u32 *) cfg_addr, val);
87 		break;
88 	}
89 
90 	return PCIBIOS_SUCCESSFUL;
91 }
92 
93 void tsi108_clear_pci_error(u32 pci_cfg_base)
94 {
95 	u32 err_stat, err_addr, pci_stat;
96 
97 	/*
98 	 * Quietly clear PB and PCI error flags set as result
99 	 * of PCI/X configuration read requests.
100 	 */
101 
102 	/* Read PB Error Log Registers */
103 
104 	err_stat = tsi108_read_reg(TSI108_PB_OFFSET + TSI108_PB_ERRCS);
105 	err_addr = tsi108_read_reg(TSI108_PB_OFFSET + TSI108_PB_AERR);
106 
107 	if (err_stat & TSI108_PB_ERRCS_ES) {
108 		/* Clear error flag */
109 		tsi108_write_reg(TSI108_PB_OFFSET + TSI108_PB_ERRCS,
110 				 TSI108_PB_ERRCS_ES);
111 
112 		/* Clear read error reported in PB_ISR */
113 		tsi108_write_reg(TSI108_PB_OFFSET + TSI108_PB_ISR,
114 				 TSI108_PB_ISR_PBS_RD_ERR);
115 
116 		/* Clear PCI/X bus cfg errors if applicable */
117 		if ((err_addr & 0xFF000000) == pci_cfg_base) {
118 			pci_stat =
119 			    tsi108_read_reg(TSI108_PCI_OFFSET + TSI108_PCI_CSR);
120 			tsi108_write_reg(TSI108_PCI_OFFSET + TSI108_PCI_CSR,
121 					 pci_stat);
122 		}
123 	}
124 
125 	return;
126 }
127 
128 #define __tsi108_read_pci_config(x, addr, op)		\
129 	__asm__ __volatile__(				\
130 		"	"op" %0,0,%1\n"		\
131 		"1:	eieio\n"			\
132 		"2:\n"					\
133 		".section .fixup,\"ax\"\n"		\
134 		"3:	li %0,-1\n"			\
135 		"	b 2b\n"				\
136 		".section __ex_table,\"a\"\n"		\
137 		"	.align 2\n"			\
138 		"	.long 1b,3b\n"			\
139 		".text"					\
140 		: "=r"(x) : "r"(addr))
141 
142 int
143 tsi108_direct_read_config(struct pci_bus *bus, unsigned int devfn, int offset,
144 			  int len, u32 * val)
145 {
146 	volatile unsigned char *cfg_addr;
147 	u32 temp;
148 
149 	if (ppc_md.pci_exclude_device)
150 		if (ppc_md.pci_exclude_device(bus->number, devfn))
151 			return PCIBIOS_DEVICE_NOT_FOUND;
152 
153 	cfg_addr = (unsigned char *)(tsi_mk_config_addr(bus->number,
154 							devfn,
155 							offset) | (offset &
156 								   0x03));
157 
158 	switch (len) {
159 	case 1:
160 		__tsi108_read_pci_config(temp, cfg_addr, "lbzx");
161 		break;
162 	case 2:
163 		__tsi108_read_pci_config(temp, cfg_addr, "lhbrx");
164 		break;
165 	default:
166 		__tsi108_read_pci_config(temp, cfg_addr, "lwbrx");
167 		break;
168 	}
169 
170 	*val = temp;
171 
172 #ifdef DEBUG
173 	if ((0xFFFFFFFF != temp) && (0xFFFF != temp) && (0xFF != temp)) {
174 		printk("PCI CFG read : ");
175 		printk("%d:0x%x:0x%x ", bus->number, devfn, offset);
176 		printk("%d ADDR=0x%08x ", len, (uint) cfg_addr);
177 		printk("data = 0x%x\n", *val);
178 	}
179 #endif
180 	return PCIBIOS_SUCCESSFUL;
181 }
182 
183 void tsi108_clear_pci_cfg_error(void)
184 {
185 	tsi108_clear_pci_error(TSI108_PCI_CFG_BASE_PHYS);
186 }
187 
188 static struct pci_ops tsi108_direct_pci_ops = {
189 	tsi108_direct_read_config,
190 	tsi108_direct_write_config
191 };
192 
193 int __init tsi108_setup_pci(struct device_node *dev)
194 {
195 	int len;
196 	struct pci_controller *hose;
197 	struct resource rsrc;
198 	int *bus_range;
199 	int primary = 0, has_address = 0;
200 
201 	/* PCI Config mapping */
202 	tsi108_pci_cfg_base = (u32)ioremap(TSI108_PCI_CFG_BASE_PHYS,
203 			TSI108_PCI_CFG_SIZE);
204 	DBG("TSI_PCI: %s tsi108_pci_cfg_base=0x%x\n", __FUNCTION__,
205 	    tsi108_pci_cfg_base);
206 
207 	/* Fetch host bridge registers address */
208 	has_address = (of_address_to_resource(dev, 0, &rsrc) == 0);
209 
210 	/* Get bus range if any */
211 	bus_range = (int *)get_property(dev, "bus-range", &len);
212 	if (bus_range == NULL || len < 2 * sizeof(int)) {
213 		printk(KERN_WARNING "Can't get bus-range for %s, assume"
214 		       " bus 0\n", dev->full_name);
215 	}
216 
217 	hose = pcibios_alloc_controller();
218 
219 	if (!hose) {
220 		printk("PCI Host bridge init failed\n");
221 		return -ENOMEM;
222 	}
223 	hose->arch_data = dev;
224 	hose->set_cfg_type = 1;
225 
226 	hose->first_busno = bus_range ? bus_range[0] : 0;
227 	hose->last_busno = bus_range ? bus_range[1] : 0xff;
228 
229 	(hose)->ops = &tsi108_direct_pci_ops;
230 
231 	printk(KERN_INFO "Found tsi108 PCI host bridge at 0x%08lx. "
232 	       "Firmware bus number: %d->%d\n",
233 	       rsrc.start, hose->first_busno, hose->last_busno);
234 
235 	/* Interpret the "ranges" property */
236 	/* This also maps the I/O region and sets isa_io/mem_base */
237 	pci_process_bridge_OF_ranges(hose, dev, primary);
238 	return 0;
239 }
240 
241 /*
242  * Low level utility functions
243  */
244 
245 static void tsi108_pci_int_mask(u_int irq)
246 {
247 	u_int irp_cfg;
248 	int int_line = (irq - IRQ_PCI_INTAD_BASE);
249 
250 	irp_cfg = tsi108_read_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_CFG_CTL);
251 	mb();
252 	irp_cfg |= (1 << int_line);	/* INTx_DIR = output */
253 	irp_cfg &= ~(3 << (8 + (int_line * 2)));	/* INTx_TYPE = unused */
254 	tsi108_write_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_CFG_CTL, irp_cfg);
255 	mb();
256 	irp_cfg = tsi108_read_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_CFG_CTL);
257 }
258 
259 static void tsi108_pci_int_unmask(u_int irq)
260 {
261 	u_int irp_cfg;
262 	int int_line = (irq - IRQ_PCI_INTAD_BASE);
263 
264 	irp_cfg = tsi108_read_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_CFG_CTL);
265 	mb();
266 	irp_cfg &= ~(1 << int_line);
267 	irp_cfg |= (3 << (8 + (int_line * 2)));
268 	tsi108_write_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_CFG_CTL, irp_cfg);
269 	mb();
270 }
271 
272 static void init_pci_source(void)
273 {
274 	tsi108_write_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_CFG_CTL,
275 			0x0000ff00);
276 	tsi108_write_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_ENABLE,
277 			TSI108_PCI_IRP_ENABLE_P_INT);
278 	mb();
279 }
280 
281 static inline int get_pci_source(void)
282 {
283 	u_int temp = 0;
284 	int irq = -1;
285 	int i;
286 	u_int pci_irp_stat;
287 	static int mask = 0;
288 
289 	/* Read PCI/X block interrupt status register */
290 	pci_irp_stat = tsi108_read_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_STAT);
291 	mb();
292 
293 	if (pci_irp_stat & TSI108_PCI_IRP_STAT_P_INT) {
294 		/* Process Interrupt from PCI bus INTA# - INTD# lines */
295 		temp =
296 		    tsi108_read_reg(TSI108_PCI_OFFSET +
297 				    TSI108_PCI_IRP_INTAD) & 0xf;
298 		mb();
299 		for (i = 0; i < 4; i++, mask++) {
300 			if (temp & (1 << mask % 4)) {
301 				irq = IRQ_PCI_INTA + mask % 4;
302 				mask++;
303 				break;
304 			}
305 		}
306 
307 		/* Disable interrupts from PCI block */
308 		temp = tsi108_read_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_ENABLE);
309 		tsi108_write_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_ENABLE,
310 				temp & ~TSI108_PCI_IRP_ENABLE_P_INT);
311 		mb();
312 		(void)tsi108_read_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_ENABLE);
313 		mb();
314 	}
315 #ifdef DEBUG
316 	else {
317 		printk("TSI108_PIC: error in TSI108_PCI_IRP_STAT\n");
318 		pci_irp_stat =
319 		    tsi108_read_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_STAT);
320 		temp =
321 		    tsi108_read_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_INTAD);
322 		mb();
323 		printk(">> stat=0x%08x intad=0x%08x ", pci_irp_stat, temp);
324 		temp =
325 		    tsi108_read_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_CFG_CTL);
326 		mb();
327 		printk("cfg_ctl=0x%08x ", temp);
328 		temp =
329 		    tsi108_read_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_ENABLE);
330 		mb();
331 		printk("irp_enable=0x%08x\n", temp);
332 	}
333 #endif	/* end of DEBUG */
334 
335 	return irq;
336 }
337 
338 
339 /*
340  * Linux descriptor level callbacks
341  */
342 
343 static void tsi108_pci_irq_enable(u_int irq)
344 {
345 	tsi108_pci_int_unmask(irq);
346 }
347 
348 static void tsi108_pci_irq_disable(u_int irq)
349 {
350 	tsi108_pci_int_mask(irq);
351 }
352 
353 static void tsi108_pci_irq_ack(u_int irq)
354 {
355 	tsi108_pci_int_mask(irq);
356 }
357 
358 static void tsi108_pci_irq_end(u_int irq)
359 {
360 	tsi108_pci_int_unmask(irq);
361 
362 	/* Enable interrupts from PCI block */
363 	tsi108_write_reg(TSI108_PCI_OFFSET + TSI108_PCI_IRP_ENABLE,
364 			 tsi108_read_reg(TSI108_PCI_OFFSET +
365 					 TSI108_PCI_IRP_ENABLE) |
366 			 TSI108_PCI_IRP_ENABLE_P_INT);
367 	mb();
368 }
369 
370 /*
371  * Interrupt controller descriptor for cascaded PCI interrupt controller.
372  */
373 
374 struct hw_interrupt_type tsi108_pci_irq = {
375 	.typename = "tsi108_PCI_int",
376 	.enable = tsi108_pci_irq_enable,
377 	.disable = tsi108_pci_irq_disable,
378 	.ack = tsi108_pci_irq_ack,
379 	.end = tsi108_pci_irq_end,
380 };
381 
382 /*
383  * Exported functions
384  */
385 
386 /*
387  * The Tsi108 PCI interrupts initialization routine.
388  *
389  * The INTA# - INTD# interrupts on the PCI bus are reported by the PCI block
390  * to the MPIC using single interrupt source (IRQ_TSI108_PCI). Therefore the
391  * PCI block has to be treated as a cascaded interrupt controller connected
392  * to the MPIC.
393  */
394 
395 void __init tsi108_pci_int_init(void)
396 {
397 	u_int i;
398 
399 	DBG("Tsi108_pci_int_init: initializing PCI interrupts\n");
400 
401 	for (i = 0; i < NUM_PCI_IRQS; i++) {
402 		irq_desc[i + IRQ_PCI_INTAD_BASE].handler = &tsi108_pci_irq;
403 		irq_desc[i + IRQ_PCI_INTAD_BASE].status |= IRQ_LEVEL;
404 	}
405 
406 	init_pci_source();
407 }
408 
409 int tsi108_irq_cascade(struct pt_regs *regs, void *unused)
410 {
411 	return get_pci_source();
412 }
413