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
sh7780_pci_err_irq(int irq,void * dev_id)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
sh7780_pci_serr_irq(int irq,void * dev_id)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
sh7780_pci_setup_irqs(struct pci_channel * hose)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
sh7780_pci_teardown_irqs(struct pci_channel * hose)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
sh7780_pci66_init(struct pci_channel * hose)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
sh7780_pci_init(void)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
