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 error" },
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
sh7780_pci_err_irq(int irq,void * dev_id)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
sh7780_pci_serr_irq(int irq,void * dev_id)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
sh7780_pci_setup_irqs(struct pci_channel * hose)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, 0,
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
sh7780_pci_teardown_irqs(struct pci_channel * hose)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
sh7780_pci66_init(struct pci_channel * hose)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
sh7780_pci_init(void)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