xref: /openbmc/linux/arch/sh/drivers/pci/pci-sh7780.c (revision 293d5b43)
1 /*
2  * Low-Level PCI Support for the SH7780
3  *
4  *  Copyright (C) 2005 - 2010  Paul Mundt
5  *
6  * This file is subject to the terms and conditions of the GNU General Public
7  * License.  See the file "COPYING" in the main directory of this archive
8  * for more details.
9  */
10 #include <linux/types.h>
11 #include <linux/kernel.h>
12 #include <linux/init.h>
13 #include <linux/pci.h>
14 #include <linux/interrupt.h>
15 #include <linux/timer.h>
16 #include <linux/irq.h>
17 #include <linux/errno.h>
18 #include <linux/delay.h>
19 #include <linux/log2.h>
20 #include "pci-sh4.h"
21 #include <asm/mmu.h>
22 #include <asm/sizes.h>
23 
24 #if defined(CONFIG_CPU_BIG_ENDIAN)
25 # define PCICR_ENDIANNESS SH4_PCICR_BSWP
26 #else
27 # define PCICR_ENDIANNESS 0
28 #endif
29 
30 
31 static struct resource sh7785_pci_resources[] = {
32 	{
33 		.name	= "PCI IO",
34 		.start	= 0x1000,
35 		.end	= SZ_4M - 1,
36 		.flags	= IORESOURCE_IO,
37 	}, {
38 		.name	= "PCI MEM 0",
39 		.start	= 0xfd000000,
40 		.end	= 0xfd000000 + SZ_16M - 1,
41 		.flags	= IORESOURCE_MEM,
42 	}, {
43 		.name	= "PCI MEM 1",
44 		.start	= 0x10000000,
45 		.end	= 0x10000000 + SZ_64M - 1,
46 		.flags	= IORESOURCE_MEM,
47 	}, {
48 		/*
49 		 * 32-bit only resources must be last.
50 		 */
51 		.name	= "PCI MEM 2",
52 		.start	= 0xc0000000,
53 		.end	= 0xc0000000 + SZ_512M - 1,
54 		.flags	= IORESOURCE_MEM | IORESOURCE_MEM_32BIT,
55 	},
56 };
57 
58 static struct pci_channel sh7780_pci_controller = {
59 	.pci_ops	= &sh4_pci_ops,
60 	.resources	= sh7785_pci_resources,
61 	.nr_resources	= ARRAY_SIZE(sh7785_pci_resources),
62 	.io_offset	= 0,
63 	.mem_offset	= 0,
64 	.io_map_base	= 0xfe200000,
65 	.serr_irq	= evt2irq(0xa00),
66 	.err_irq	= evt2irq(0xaa0),
67 };
68 
69 struct pci_errors {
70 	unsigned int	mask;
71 	const char	*str;
72 } pci_arbiter_errors[] = {
73 	{ SH4_PCIAINT_MBKN,	"master broken" },
74 	{ SH4_PCIAINT_TBTO,	"target bus time out" },
75 	{ SH4_PCIAINT_MBTO,	"master bus time out" },
76 	{ SH4_PCIAINT_TABT,	"target abort" },
77 	{ SH4_PCIAINT_MABT,	"master abort" },
78 	{ SH4_PCIAINT_RDPE,	"read data parity error" },
79 	{ SH4_PCIAINT_WDPE,	"write data parity error" },
80 }, pci_interrupt_errors[] = {
81 	{ SH4_PCIINT_MLCK,	"master lock error" },
82 	{ SH4_PCIINT_TABT,	"target-target abort" },
83 	{ SH4_PCIINT_TRET,	"target retry time out" },
84 	{ SH4_PCIINT_MFDE,	"master function disable error" },
85 	{ SH4_PCIINT_PRTY,	"address parity error" },
86 	{ SH4_PCIINT_SERR,	"SERR" },
87 	{ SH4_PCIINT_TWDP,	"data parity error for target write" },
88 	{ SH4_PCIINT_TRDP,	"PERR detected for target read" },
89 	{ SH4_PCIINT_MTABT,	"target abort for master" },
90 	{ SH4_PCIINT_MMABT,	"master abort for master" },
91 	{ SH4_PCIINT_MWPD,	"master write data parity error" },
92 	{ SH4_PCIINT_MRPD,	"master read data parity error" },
93 };
94 
95 static irqreturn_t sh7780_pci_err_irq(int irq, void *dev_id)
96 {
97 	struct pci_channel *hose = dev_id;
98 	unsigned long addr;
99 	unsigned int status;
100 	unsigned int cmd;
101 	int i;
102 
103 	addr = __raw_readl(hose->reg_base + SH4_PCIALR);
104 
105 	/*
106 	 * Handle status errors.
107 	 */
108 	status = __raw_readw(hose->reg_base + PCI_STATUS);
109 	if (status & (PCI_STATUS_PARITY |
110 		      PCI_STATUS_DETECTED_PARITY |
111 		      PCI_STATUS_SIG_TARGET_ABORT |
112 		      PCI_STATUS_REC_TARGET_ABORT |
113 		      PCI_STATUS_REC_MASTER_ABORT)) {
114 		cmd = pcibios_handle_status_errors(addr, status, hose);
115 		if (likely(cmd))
116 			__raw_writew(cmd, hose->reg_base + PCI_STATUS);
117 	}
118 
119 	/*
120 	 * Handle arbiter errors.
121 	 */
122 	status = __raw_readl(hose->reg_base + SH4_PCIAINT);
123 	for (i = cmd = 0; i < ARRAY_SIZE(pci_arbiter_errors); i++) {
124 		if (status & pci_arbiter_errors[i].mask) {
125 			printk(KERN_DEBUG "PCI: %s, addr=%08lx\n",
126 			       pci_arbiter_errors[i].str, addr);
127 			cmd |= pci_arbiter_errors[i].mask;
128 		}
129 	}
130 	__raw_writel(cmd, hose->reg_base + SH4_PCIAINT);
131 
132 	/*
133 	 * Handle the remaining PCI errors.
134 	 */
135 	status = __raw_readl(hose->reg_base + SH4_PCIINT);
136 	for (i = cmd = 0; i < ARRAY_SIZE(pci_interrupt_errors); i++) {
137 		if (status & pci_interrupt_errors[i].mask) {
138 			printk(KERN_DEBUG "PCI: %s, addr=%08lx\n",
139 			       pci_interrupt_errors[i].str, addr);
140 			cmd |= pci_interrupt_errors[i].mask;
141 		}
142 	}
143 	__raw_writel(cmd, hose->reg_base + SH4_PCIINT);
144 
145 	return IRQ_HANDLED;
146 }
147 
148 static irqreturn_t sh7780_pci_serr_irq(int irq, void *dev_id)
149 {
150 	struct pci_channel *hose = dev_id;
151 
152 	printk(KERN_DEBUG "PCI: system error received: ");
153 	pcibios_report_status(PCI_STATUS_SIG_SYSTEM_ERROR, 1);
154 	printk("\n");
155 
156 	/* Deassert SERR */
157 	__raw_writel(SH4_PCIINTM_SDIM, hose->reg_base + SH4_PCIINTM);
158 
159 	/* Back off the IRQ for awhile */
160 	disable_irq_nosync(irq);
161 	hose->serr_timer.expires = jiffies + HZ;
162 	add_timer(&hose->serr_timer);
163 
164 	return IRQ_HANDLED;
165 }
166 
167 static int __init sh7780_pci_setup_irqs(struct pci_channel *hose)
168 {
169 	int ret;
170 
171 	/* Clear out PCI arbiter IRQs */
172 	__raw_writel(0, hose->reg_base + SH4_PCIAINT);
173 
174 	/* Clear all error conditions */
175 	__raw_writew(PCI_STATUS_DETECTED_PARITY  | \
176 		     PCI_STATUS_SIG_SYSTEM_ERROR | \
177 		     PCI_STATUS_REC_MASTER_ABORT | \
178 		     PCI_STATUS_REC_TARGET_ABORT | \
179 		     PCI_STATUS_SIG_TARGET_ABORT | \
180 		     PCI_STATUS_PARITY, hose->reg_base + PCI_STATUS);
181 
182 	ret = request_irq(hose->serr_irq, sh7780_pci_serr_irq, 0,
183 			  "PCI SERR interrupt", hose);
184 	if (unlikely(ret)) {
185 		printk(KERN_ERR "PCI: Failed hooking SERR IRQ\n");
186 		return ret;
187 	}
188 
189 	/*
190 	 * The PCI ERR IRQ needs to be IRQF_SHARED since all of the power
191 	 * down IRQ vectors are routed through the ERR IRQ vector. We
192 	 * only request_irq() once as there is only a single masking
193 	 * source for multiple events.
194 	 */
195 	ret = request_irq(hose->err_irq, sh7780_pci_err_irq, IRQF_SHARED,
196 			  "PCI ERR interrupt", hose);
197 	if (unlikely(ret)) {
198 		free_irq(hose->serr_irq, hose);
199 		return ret;
200 	}
201 
202 	/* Unmask all of the arbiter IRQs. */
203 	__raw_writel(SH4_PCIAINT_MBKN | SH4_PCIAINT_TBTO | SH4_PCIAINT_MBTO | \
204 		     SH4_PCIAINT_TABT | SH4_PCIAINT_MABT | SH4_PCIAINT_RDPE | \
205 		     SH4_PCIAINT_WDPE, hose->reg_base + SH4_PCIAINTM);
206 
207 	/* Unmask all of the PCI IRQs */
208 	__raw_writel(SH4_PCIINTM_TTADIM  | SH4_PCIINTM_TMTOIM  | \
209 		     SH4_PCIINTM_MDEIM   | SH4_PCIINTM_APEDIM  | \
210 		     SH4_PCIINTM_SDIM    | SH4_PCIINTM_DPEITWM | \
211 		     SH4_PCIINTM_PEDITRM | SH4_PCIINTM_TADIMM  | \
212 		     SH4_PCIINTM_MADIMM  | SH4_PCIINTM_MWPDIM  | \
213 		     SH4_PCIINTM_MRDPEIM, hose->reg_base + SH4_PCIINTM);
214 
215 	return ret;
216 }
217 
218 static inline void __init sh7780_pci_teardown_irqs(struct pci_channel *hose)
219 {
220 	free_irq(hose->err_irq, hose);
221 	free_irq(hose->serr_irq, hose);
222 }
223 
224 static void __init sh7780_pci66_init(struct pci_channel *hose)
225 {
226 	unsigned int tmp;
227 
228 	if (!pci_is_66mhz_capable(hose, 0, 0))
229 		return;
230 
231 	/* Enable register access */
232 	tmp = __raw_readl(hose->reg_base + SH4_PCICR);
233 	tmp |= SH4_PCICR_PREFIX;
234 	__raw_writel(tmp, hose->reg_base + SH4_PCICR);
235 
236 	/* Enable 66MHz operation */
237 	tmp = __raw_readw(hose->reg_base + PCI_STATUS);
238 	tmp |= PCI_STATUS_66MHZ;
239 	__raw_writew(tmp, hose->reg_base + PCI_STATUS);
240 
241 	/* Done */
242 	tmp = __raw_readl(hose->reg_base + SH4_PCICR);
243 	tmp |= SH4_PCICR_PREFIX | SH4_PCICR_CFIN;
244 	__raw_writel(tmp, hose->reg_base + SH4_PCICR);
245 }
246 
247 static int __init sh7780_pci_init(void)
248 {
249 	struct pci_channel *chan = &sh7780_pci_controller;
250 	phys_addr_t memphys;
251 	size_t memsize;
252 	unsigned int id;
253 	const char *type;
254 	int ret, i;
255 
256 	printk(KERN_NOTICE "PCI: Starting initialization.\n");
257 
258 	chan->reg_base = 0xfe040000;
259 
260 	/* Enable CPU access to the PCIC registers. */
261 	__raw_writel(PCIECR_ENBL, PCIECR);
262 
263 	/* Reset */
264 	__raw_writel(SH4_PCICR_PREFIX | SH4_PCICR_PRST | PCICR_ENDIANNESS,
265 		     chan->reg_base + SH4_PCICR);
266 
267 	/*
268 	 * Wait for it to come back up. The spec says to allow for up to
269 	 * 1 second after toggling the reset pin, but in practice 100ms
270 	 * is more than enough.
271 	 */
272 	mdelay(100);
273 
274 	id = __raw_readw(chan->reg_base + PCI_VENDOR_ID);
275 	if (id != PCI_VENDOR_ID_RENESAS) {
276 		printk(KERN_ERR "PCI: Unknown vendor ID 0x%04x.\n", id);
277 		return -ENODEV;
278 	}
279 
280 	id = __raw_readw(chan->reg_base + PCI_DEVICE_ID);
281 	type = (id == PCI_DEVICE_ID_RENESAS_SH7763) ? "SH7763" :
282 	       (id == PCI_DEVICE_ID_RENESAS_SH7780) ? "SH7780" :
283 	       (id == PCI_DEVICE_ID_RENESAS_SH7781) ? "SH7781" :
284 	       (id == PCI_DEVICE_ID_RENESAS_SH7785) ? "SH7785" :
285 					  NULL;
286 	if (unlikely(!type)) {
287 		printk(KERN_ERR "PCI: Found an unsupported Renesas host "
288 		       "controller, device id 0x%04x.\n", id);
289 		return -EINVAL;
290 	}
291 
292 	printk(KERN_NOTICE "PCI: Found a Renesas %s host "
293 	       "controller, revision %d.\n", type,
294 	       __raw_readb(chan->reg_base + PCI_REVISION_ID));
295 
296 	/*
297 	 * Now throw it in to register initialization mode and
298 	 * start the real work.
299 	 */
300 	__raw_writel(SH4_PCICR_PREFIX | PCICR_ENDIANNESS,
301 		     chan->reg_base + SH4_PCICR);
302 
303 	memphys = __pa(memory_start);
304 	memsize = roundup_pow_of_two(memory_end - memory_start);
305 
306 	/*
307 	 * If there's more than 512MB of memory, we need to roll over to
308 	 * LAR1/LSR1.
309 	 */
310 	if (memsize > SZ_512M) {
311 		__raw_writel(memphys + SZ_512M, chan->reg_base + SH4_PCILAR1);
312 		__raw_writel((((memsize - SZ_512M) - SZ_1M) & 0x1ff00000) | 1,
313 			     chan->reg_base + SH4_PCILSR1);
314 		memsize = SZ_512M;
315 	} else {
316 		/*
317 		 * Otherwise just zero it out and disable it.
318 		 */
319 		__raw_writel(0, chan->reg_base + SH4_PCILAR1);
320 		__raw_writel(0, chan->reg_base + SH4_PCILSR1);
321 	}
322 
323 	/*
324 	 * LAR0/LSR0 covers up to the first 512MB, which is enough to
325 	 * cover all of lowmem on most platforms.
326 	 */
327 	__raw_writel(memphys, chan->reg_base + SH4_PCILAR0);
328 	__raw_writel(((memsize - SZ_1M) & 0x1ff00000) | 1,
329 		     chan->reg_base + SH4_PCILSR0);
330 
331 	/*
332 	 * Hook up the ERR and SERR IRQs.
333 	 */
334 	ret = sh7780_pci_setup_irqs(chan);
335 	if (unlikely(ret))
336 		return ret;
337 
338 	/*
339 	 * Disable the cache snoop controller for non-coherent DMA.
340 	 */
341 	__raw_writel(0, chan->reg_base + SH7780_PCICSCR0);
342 	__raw_writel(0, chan->reg_base + SH7780_PCICSAR0);
343 	__raw_writel(0, chan->reg_base + SH7780_PCICSCR1);
344 	__raw_writel(0, chan->reg_base + SH7780_PCICSAR1);
345 
346 	/*
347 	 * Setup the memory BARs
348 	 */
349 	for (i = 1; i < chan->nr_resources; i++) {
350 		struct resource *res = chan->resources + i;
351 		resource_size_t size;
352 
353 		if (unlikely(res->flags & IORESOURCE_IO))
354 			continue;
355 
356 		/*
357 		 * Make sure we're in the right physical addressing mode
358 		 * for dealing with the resource.
359 		 */
360 		if ((res->flags & IORESOURCE_MEM_32BIT) && __in_29bit_mode()) {
361 			chan->nr_resources--;
362 			continue;
363 		}
364 
365 		size = resource_size(res);
366 
367 		/*
368 		 * The MBMR mask is calculated in units of 256kB, which
369 		 * keeps things pretty simple.
370 		 */
371 		__raw_writel(((roundup_pow_of_two(size) / SZ_256K) - 1) << 18,
372 			     chan->reg_base + SH7780_PCIMBMR(i - 1));
373 		__raw_writel(res->start, chan->reg_base + SH7780_PCIMBR(i - 1));
374 	}
375 
376 	/*
377 	 * And I/O.
378 	 */
379 	__raw_writel(0, chan->reg_base + PCI_BASE_ADDRESS_0);
380 	__raw_writel(0, chan->reg_base + SH7780_PCIIOBR);
381 	__raw_writel(0, chan->reg_base + SH7780_PCIIOBMR);
382 
383 	__raw_writew(PCI_COMMAND_SERR   | PCI_COMMAND_WAIT   | \
384 		     PCI_COMMAND_PARITY | PCI_COMMAND_MASTER | \
385 		     PCI_COMMAND_MEMORY, chan->reg_base + PCI_COMMAND);
386 
387 	/*
388 	 * Initialization mode complete, release the control register and
389 	 * enable round robin mode to stop device overruns/starvation.
390 	 */
391 	__raw_writel(SH4_PCICR_PREFIX | SH4_PCICR_CFIN | SH4_PCICR_FTO |
392 		     PCICR_ENDIANNESS,
393 		     chan->reg_base + SH4_PCICR);
394 
395 	ret = register_pci_controller(chan);
396 	if (unlikely(ret))
397 		goto err;
398 
399 	sh7780_pci66_init(chan);
400 
401 	printk(KERN_NOTICE "PCI: Running at %dMHz.\n",
402 	       (__raw_readw(chan->reg_base + PCI_STATUS) & PCI_STATUS_66MHZ) ?
403 	       66 : 33);
404 
405 	return 0;
406 
407 err:
408 	sh7780_pci_teardown_irqs(chan);
409 	return ret;
410 }
411 arch_initcall(sh7780_pci_init);
412