xref: /openbmc/linux/arch/sh/drivers/pci/pci-sh7780.c (revision 4800cd83)
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 static struct resource sh7785_pci_resources[] = {
25 	{
26 		.name	= "PCI IO",
27 		.start	= 0x1000,
28 		.end	= SZ_4M - 1,
29 		.flags	= IORESOURCE_IO,
30 	}, {
31 		.name	= "PCI MEM 0",
32 		.start	= 0xfd000000,
33 		.end	= 0xfd000000 + SZ_16M - 1,
34 		.flags	= IORESOURCE_MEM,
35 	}, {
36 		.name	= "PCI MEM 1",
37 		.start	= 0x10000000,
38 		.end	= 0x10000000 + SZ_64M - 1,
39 		.flags	= IORESOURCE_MEM,
40 	}, {
41 		/*
42 		 * 32-bit only resources must be last.
43 		 */
44 		.name	= "PCI MEM 2",
45 		.start	= 0xc0000000,
46 		.end	= 0xc0000000 + SZ_512M - 1,
47 		.flags	= IORESOURCE_MEM | IORESOURCE_MEM_32BIT,
48 	},
49 };
50 
51 static struct pci_channel sh7780_pci_controller = {
52 	.pci_ops	= &sh4_pci_ops,
53 	.resources	= sh7785_pci_resources,
54 	.nr_resources	= ARRAY_SIZE(sh7785_pci_resources),
55 	.io_offset	= 0,
56 	.mem_offset	= 0,
57 	.io_map_base	= 0xfe200000,
58 	.serr_irq	= evt2irq(0xa00),
59 	.err_irq	= evt2irq(0xaa0),
60 };
61 
62 struct pci_errors {
63 	unsigned int	mask;
64 	const char	*str;
65 } pci_arbiter_errors[] = {
66 	{ SH4_PCIAINT_MBKN,	"master broken" },
67 	{ SH4_PCIAINT_TBTO,	"target bus time out" },
68 	{ SH4_PCIAINT_MBTO,	"master bus time out" },
69 	{ SH4_PCIAINT_TABT,	"target abort" },
70 	{ SH4_PCIAINT_MABT,	"master abort" },
71 	{ SH4_PCIAINT_RDPE,	"read data parity error" },
72 	{ SH4_PCIAINT_WDPE,	"write data parity error" },
73 }, pci_interrupt_errors[] = {
74 	{ SH4_PCIINT_MLCK,	"master lock error" },
75 	{ SH4_PCIINT_TABT,	"target-target abort" },
76 	{ SH4_PCIINT_TRET,	"target retry time out" },
77 	{ SH4_PCIINT_MFDE,	"master function disable erorr" },
78 	{ SH4_PCIINT_PRTY,	"address parity error" },
79 	{ SH4_PCIINT_SERR,	"SERR" },
80 	{ SH4_PCIINT_TWDP,	"data parity error for target write" },
81 	{ SH4_PCIINT_TRDP,	"PERR detected for target read" },
82 	{ SH4_PCIINT_MTABT,	"target abort for master" },
83 	{ SH4_PCIINT_MMABT,	"master abort for master" },
84 	{ SH4_PCIINT_MWPD,	"master write data parity error" },
85 	{ SH4_PCIINT_MRPD,	"master read data parity error" },
86 };
87 
88 static irqreturn_t sh7780_pci_err_irq(int irq, void *dev_id)
89 {
90 	struct pci_channel *hose = dev_id;
91 	unsigned long addr;
92 	unsigned int status;
93 	unsigned int cmd;
94 	int i;
95 
96 	addr = __raw_readl(hose->reg_base + SH4_PCIALR);
97 
98 	/*
99 	 * Handle status errors.
100 	 */
101 	status = __raw_readw(hose->reg_base + PCI_STATUS);
102 	if (status & (PCI_STATUS_PARITY |
103 		      PCI_STATUS_DETECTED_PARITY |
104 		      PCI_STATUS_SIG_TARGET_ABORT |
105 		      PCI_STATUS_REC_TARGET_ABORT |
106 		      PCI_STATUS_REC_MASTER_ABORT)) {
107 		cmd = pcibios_handle_status_errors(addr, status, hose);
108 		if (likely(cmd))
109 			__raw_writew(cmd, hose->reg_base + PCI_STATUS);
110 	}
111 
112 	/*
113 	 * Handle arbiter errors.
114 	 */
115 	status = __raw_readl(hose->reg_base + SH4_PCIAINT);
116 	for (i = cmd = 0; i < ARRAY_SIZE(pci_arbiter_errors); i++) {
117 		if (status & pci_arbiter_errors[i].mask) {
118 			printk(KERN_DEBUG "PCI: %s, addr=%08lx\n",
119 			       pci_arbiter_errors[i].str, addr);
120 			cmd |= pci_arbiter_errors[i].mask;
121 		}
122 	}
123 	__raw_writel(cmd, hose->reg_base + SH4_PCIAINT);
124 
125 	/*
126 	 * Handle the remaining PCI errors.
127 	 */
128 	status = __raw_readl(hose->reg_base + SH4_PCIINT);
129 	for (i = cmd = 0; i < ARRAY_SIZE(pci_interrupt_errors); i++) {
130 		if (status & pci_interrupt_errors[i].mask) {
131 			printk(KERN_DEBUG "PCI: %s, addr=%08lx\n",
132 			       pci_interrupt_errors[i].str, addr);
133 			cmd |= pci_interrupt_errors[i].mask;
134 		}
135 	}
136 	__raw_writel(cmd, hose->reg_base + SH4_PCIINT);
137 
138 	return IRQ_HANDLED;
139 }
140 
141 static irqreturn_t sh7780_pci_serr_irq(int irq, void *dev_id)
142 {
143 	struct pci_channel *hose = dev_id;
144 
145 	printk(KERN_DEBUG "PCI: system error received: ");
146 	pcibios_report_status(PCI_STATUS_SIG_SYSTEM_ERROR, 1);
147 	printk("\n");
148 
149 	/* Deassert SERR */
150 	__raw_writel(SH4_PCIINTM_SDIM, hose->reg_base + SH4_PCIINTM);
151 
152 	/* Back off the IRQ for awhile */
153 	disable_irq_nosync(irq);
154 	hose->serr_timer.expires = jiffies + HZ;
155 	add_timer(&hose->serr_timer);
156 
157 	return IRQ_HANDLED;
158 }
159 
160 static int __init sh7780_pci_setup_irqs(struct pci_channel *hose)
161 {
162 	int ret;
163 
164 	/* Clear out PCI arbiter IRQs */
165 	__raw_writel(0, hose->reg_base + SH4_PCIAINT);
166 
167 	/* Clear all error conditions */
168 	__raw_writew(PCI_STATUS_DETECTED_PARITY  | \
169 		     PCI_STATUS_SIG_SYSTEM_ERROR | \
170 		     PCI_STATUS_REC_MASTER_ABORT | \
171 		     PCI_STATUS_REC_TARGET_ABORT | \
172 		     PCI_STATUS_SIG_TARGET_ABORT | \
173 		     PCI_STATUS_PARITY, hose->reg_base + PCI_STATUS);
174 
175 	ret = request_irq(hose->serr_irq, sh7780_pci_serr_irq, IRQF_DISABLED,
176 			  "PCI SERR interrupt", hose);
177 	if (unlikely(ret)) {
178 		printk(KERN_ERR "PCI: Failed hooking SERR IRQ\n");
179 		return ret;
180 	}
181 
182 	/*
183 	 * The PCI ERR IRQ needs to be IRQF_SHARED since all of the power
184 	 * down IRQ vectors are routed through the ERR IRQ vector. We
185 	 * only request_irq() once as there is only a single masking
186 	 * source for multiple events.
187 	 */
188 	ret = request_irq(hose->err_irq, sh7780_pci_err_irq, IRQF_SHARED,
189 			  "PCI ERR interrupt", hose);
190 	if (unlikely(ret)) {
191 		free_irq(hose->serr_irq, hose);
192 		return ret;
193 	}
194 
195 	/* Unmask all of the arbiter IRQs. */
196 	__raw_writel(SH4_PCIAINT_MBKN | SH4_PCIAINT_TBTO | SH4_PCIAINT_MBTO | \
197 		     SH4_PCIAINT_TABT | SH4_PCIAINT_MABT | SH4_PCIAINT_RDPE | \
198 		     SH4_PCIAINT_WDPE, hose->reg_base + SH4_PCIAINTM);
199 
200 	/* Unmask all of the PCI IRQs */
201 	__raw_writel(SH4_PCIINTM_TTADIM  | SH4_PCIINTM_TMTOIM  | \
202 		     SH4_PCIINTM_MDEIM   | SH4_PCIINTM_APEDIM  | \
203 		     SH4_PCIINTM_SDIM    | SH4_PCIINTM_DPEITWM | \
204 		     SH4_PCIINTM_PEDITRM | SH4_PCIINTM_TADIMM  | \
205 		     SH4_PCIINTM_MADIMM  | SH4_PCIINTM_MWPDIM  | \
206 		     SH4_PCIINTM_MRDPEIM, hose->reg_base + SH4_PCIINTM);
207 
208 	return ret;
209 }
210 
211 static inline void __init sh7780_pci_teardown_irqs(struct pci_channel *hose)
212 {
213 	free_irq(hose->err_irq, hose);
214 	free_irq(hose->serr_irq, hose);
215 }
216 
217 static void __init sh7780_pci66_init(struct pci_channel *hose)
218 {
219 	unsigned int tmp;
220 
221 	if (!pci_is_66mhz_capable(hose, 0, 0))
222 		return;
223 
224 	/* Enable register access */
225 	tmp = __raw_readl(hose->reg_base + SH4_PCICR);
226 	tmp |= SH4_PCICR_PREFIX;
227 	__raw_writel(tmp, hose->reg_base + SH4_PCICR);
228 
229 	/* Enable 66MHz operation */
230 	tmp = __raw_readw(hose->reg_base + PCI_STATUS);
231 	tmp |= PCI_STATUS_66MHZ;
232 	__raw_writew(tmp, hose->reg_base + PCI_STATUS);
233 
234 	/* Done */
235 	tmp = __raw_readl(hose->reg_base + SH4_PCICR);
236 	tmp |= SH4_PCICR_PREFIX | SH4_PCICR_CFIN;
237 	__raw_writel(tmp, hose->reg_base + SH4_PCICR);
238 }
239 
240 static int __init sh7780_pci_init(void)
241 {
242 	struct pci_channel *chan = &sh7780_pci_controller;
243 	phys_addr_t memphys;
244 	size_t memsize;
245 	unsigned int id;
246 	const char *type;
247 	int ret, i;
248 
249 	printk(KERN_NOTICE "PCI: Starting initialization.\n");
250 
251 	chan->reg_base = 0xfe040000;
252 
253 	/* Enable CPU access to the PCIC registers. */
254 	__raw_writel(PCIECR_ENBL, PCIECR);
255 
256 	/* Reset */
257 	__raw_writel(SH4_PCICR_PREFIX | SH4_PCICR_PRST,
258 		     chan->reg_base + SH4_PCICR);
259 
260 	/*
261 	 * Wait for it to come back up. The spec says to allow for up to
262 	 * 1 second after toggling the reset pin, but in practice 100ms
263 	 * is more than enough.
264 	 */
265 	mdelay(100);
266 
267 	id = __raw_readw(chan->reg_base + PCI_VENDOR_ID);
268 	if (id != PCI_VENDOR_ID_RENESAS) {
269 		printk(KERN_ERR "PCI: Unknown vendor ID 0x%04x.\n", id);
270 		return -ENODEV;
271 	}
272 
273 	id = __raw_readw(chan->reg_base + PCI_DEVICE_ID);
274 	type = (id == PCI_DEVICE_ID_RENESAS_SH7763) ? "SH7763" :
275 	       (id == PCI_DEVICE_ID_RENESAS_SH7780) ? "SH7780" :
276 	       (id == PCI_DEVICE_ID_RENESAS_SH7781) ? "SH7781" :
277 	       (id == PCI_DEVICE_ID_RENESAS_SH7785) ? "SH7785" :
278 					  NULL;
279 	if (unlikely(!type)) {
280 		printk(KERN_ERR "PCI: Found an unsupported Renesas host "
281 		       "controller, device id 0x%04x.\n", id);
282 		return -EINVAL;
283 	}
284 
285 	printk(KERN_NOTICE "PCI: Found a Renesas %s host "
286 	       "controller, revision %d.\n", type,
287 	       __raw_readb(chan->reg_base + PCI_REVISION_ID));
288 
289 	/*
290 	 * Now throw it in to register initialization mode and
291 	 * start the real work.
292 	 */
293 	__raw_writel(SH4_PCICR_PREFIX, chan->reg_base + SH4_PCICR);
294 
295 	memphys = __pa(memory_start);
296 	memsize = roundup_pow_of_two(memory_end - memory_start);
297 
298 	/*
299 	 * If there's more than 512MB of memory, we need to roll over to
300 	 * LAR1/LSR1.
301 	 */
302 	if (memsize > SZ_512M) {
303 		__raw_writel(memphys + SZ_512M, chan->reg_base + SH4_PCILAR1);
304 		__raw_writel((((memsize - SZ_512M) - SZ_1M) & 0x1ff00000) | 1,
305 			     chan->reg_base + SH4_PCILSR1);
306 		memsize = SZ_512M;
307 	} else {
308 		/*
309 		 * Otherwise just zero it out and disable it.
310 		 */
311 		__raw_writel(0, chan->reg_base + SH4_PCILAR1);
312 		__raw_writel(0, chan->reg_base + SH4_PCILSR1);
313 	}
314 
315 	/*
316 	 * LAR0/LSR0 covers up to the first 512MB, which is enough to
317 	 * cover all of lowmem on most platforms.
318 	 */
319 	__raw_writel(memphys, chan->reg_base + SH4_PCILAR0);
320 	__raw_writel(((memsize - SZ_1M) & 0x1ff00000) | 1,
321 		     chan->reg_base + SH4_PCILSR0);
322 
323 	/*
324 	 * Hook up the ERR and SERR IRQs.
325 	 */
326 	ret = sh7780_pci_setup_irqs(chan);
327 	if (unlikely(ret))
328 		return ret;
329 
330 	/*
331 	 * Disable the cache snoop controller for non-coherent DMA.
332 	 */
333 	__raw_writel(0, chan->reg_base + SH7780_PCICSCR0);
334 	__raw_writel(0, chan->reg_base + SH7780_PCICSAR0);
335 	__raw_writel(0, chan->reg_base + SH7780_PCICSCR1);
336 	__raw_writel(0, chan->reg_base + SH7780_PCICSAR1);
337 
338 	/*
339 	 * Setup the memory BARs
340 	 */
341 	for (i = 1; i < chan->nr_resources; i++) {
342 		struct resource *res = chan->resources + i;
343 		resource_size_t size;
344 
345 		if (unlikely(res->flags & IORESOURCE_IO))
346 			continue;
347 
348 		/*
349 		 * Make sure we're in the right physical addressing mode
350 		 * for dealing with the resource.
351 		 */
352 		if ((res->flags & IORESOURCE_MEM_32BIT) && __in_29bit_mode()) {
353 			chan->nr_resources--;
354 			continue;
355 		}
356 
357 		size = resource_size(res);
358 
359 		/*
360 		 * The MBMR mask is calculated in units of 256kB, which
361 		 * keeps things pretty simple.
362 		 */
363 		__raw_writel(((roundup_pow_of_two(size) / SZ_256K) - 1) << 18,
364 			     chan->reg_base + SH7780_PCIMBMR(i - 1));
365 		__raw_writel(res->start, chan->reg_base + SH7780_PCIMBR(i - 1));
366 	}
367 
368 	/*
369 	 * And I/O.
370 	 */
371 	__raw_writel(0, chan->reg_base + PCI_BASE_ADDRESS_0);
372 	__raw_writel(0, chan->reg_base + SH7780_PCIIOBR);
373 	__raw_writel(0, chan->reg_base + SH7780_PCIIOBMR);
374 
375 	__raw_writew(PCI_COMMAND_SERR   | PCI_COMMAND_WAIT   | \
376 		     PCI_COMMAND_PARITY | PCI_COMMAND_MASTER | \
377 		     PCI_COMMAND_MEMORY, chan->reg_base + PCI_COMMAND);
378 
379 	/*
380 	 * Initialization mode complete, release the control register and
381 	 * enable round robin mode to stop device overruns/starvation.
382 	 */
383 	__raw_writel(SH4_PCICR_PREFIX | SH4_PCICR_CFIN | SH4_PCICR_FTO,
384 		     chan->reg_base + SH4_PCICR);
385 
386 	ret = register_pci_controller(chan);
387 	if (unlikely(ret))
388 		goto err;
389 
390 	sh7780_pci66_init(chan);
391 
392 	printk(KERN_NOTICE "PCI: Running at %dMHz.\n",
393 	       (__raw_readw(chan->reg_base + PCI_STATUS) & PCI_STATUS_66MHZ) ?
394 	       66 : 33);
395 
396 	return 0;
397 
398 err:
399 	sh7780_pci_teardown_irqs(chan);
400 	return ret;
401 }
402 arch_initcall(sh7780_pci_init);
403