1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Low-Level PCI Support for the SH7780
4 *
5 * Copyright (C) 2005 - 2010 Paul Mundt
6 */
7#include <linux/types.h>
8#include <linux/kernel.h>
9#include <linux/init.h>
10#include <linux/pci.h>
11#include <linux/interrupt.h>
12#include <linux/timer.h>
13#include <linux/irq.h>
14#include <linux/errno.h>
15#include <linux/delay.h>
16#include <linux/log2.h>
17#include "pci-sh4.h"
18#include <asm/mmu.h>
19#include <linux/sizes.h>
20
21#if defined(CONFIG_CPU_BIG_ENDIAN)
22# define PCICR_ENDIANNESS SH4_PCICR_BSWP
23#else
24# define PCICR_ENDIANNESS 0
25#endif
26
27
28static struct resource sh7785_pci_resources[] = {
29 {
30 .name = "PCI IO",
31 .start = 0x1000,
32 .end = SZ_4M - 1,
33 .flags = IORESOURCE_IO,
34 }, {
35 .name = "PCI MEM 0",
36 .start = 0xfd000000,
37 .end = 0xfd000000 + SZ_16M - 1,
38 .flags = IORESOURCE_MEM,
39 }, {
40 .name = "PCI MEM 1",
41 .start = 0x10000000,
42 .end = 0x10000000 + SZ_64M - 1,
43 .flags = IORESOURCE_MEM,
44 }, {
45 /*
46 * 32-bit only resources must be last.
47 */
48 .name = "PCI MEM 2",
49 .start = 0xc0000000,
50 .end = 0xc0000000 + SZ_512M - 1,
51 .flags = IORESOURCE_MEM | IORESOURCE_MEM_32BIT,
52 },
53};
54
55static struct pci_channel sh7780_pci_controller = {
56 .pci_ops = &sh4_pci_ops,
57 .resources = sh7785_pci_resources,
58 .nr_resources = ARRAY_SIZE(sh7785_pci_resources),
59 .io_offset = 0,
60 .mem_offset = 0,
61 .io_map_base = 0xfe200000,
62 .serr_irq = evt2irq(0xa00),
63 .err_irq = evt2irq(0xaa0),
64};
65
66struct pci_errors {
67 unsigned int mask;
68 const char *str;
69} pci_arbiter_errors[] = {
70 { SH4_PCIAINT_MBKN, "master broken" },
71 { SH4_PCIAINT_TBTO, "target bus time out" },
72 { SH4_PCIAINT_MBTO, "master bus time out" },
73 { SH4_PCIAINT_TABT, "target abort" },
74 { SH4_PCIAINT_MABT, "master abort" },
75 { SH4_PCIAINT_RDPE, "read data parity error" },
76 { SH4_PCIAINT_WDPE, "write data parity error" },
77}, pci_interrupt_errors[] = {
78 { SH4_PCIINT_MLCK, "master lock error" },
79 { SH4_PCIINT_TABT, "target-target abort" },
80 { SH4_PCIINT_TRET, "target retry time out" },
81 { SH4_PCIINT_MFDE, "master function disable error" },
82 { SH4_PCIINT_PRTY, "address parity error" },
83 { SH4_PCIINT_SERR, "SERR" },
84 { SH4_PCIINT_TWDP, "data parity error for target write" },
85 { SH4_PCIINT_TRDP, "PERR detected for target read" },
86 { SH4_PCIINT_MTABT, "target abort for master" },
87 { SH4_PCIINT_MMABT, "master abort for master" },
88 { SH4_PCIINT_MWPD, "master write data parity error" },
89 { SH4_PCIINT_MRPD, "master read data parity error" },
90};
91
92static irqreturn_t sh7780_pci_err_irq(int irq, void *dev_id)
93{
94 struct pci_channel *hose = dev_id;
95 unsigned long addr;
96 unsigned int status;
97 unsigned int cmd;
98 int i;
99
100 addr = __raw_readl(addr: hose->reg_base + SH4_PCIALR);
101
102 /*
103 * Handle status errors.
104 */
105 status = __raw_readw(addr: hose->reg_base + PCI_STATUS);
106 if (status & (PCI_STATUS_PARITY |
107 PCI_STATUS_DETECTED_PARITY |
108 PCI_STATUS_SIG_TARGET_ABORT |
109 PCI_STATUS_REC_TARGET_ABORT |
110 PCI_STATUS_REC_MASTER_ABORT)) {
111 cmd = pcibios_handle_status_errors(addr, status, hose);
112 if (likely(cmd))
113 __raw_writew(val: cmd, addr: hose->reg_base + PCI_STATUS);
114 }
115
116 /*
117 * Handle arbiter errors.
118 */
119 status = __raw_readl(addr: hose->reg_base + SH4_PCIAINT);
120 for (i = cmd = 0; i < ARRAY_SIZE(pci_arbiter_errors); i++) {
121 if (status & pci_arbiter_errors[i].mask) {
122 printk(KERN_DEBUG "PCI: %s, addr=%08lx\n",
123 pci_arbiter_errors[i].str, addr);
124 cmd |= pci_arbiter_errors[i].mask;
125 }
126 }
127 __raw_writel(val: cmd, addr: hose->reg_base + SH4_PCIAINT);
128
129 /*
130 * Handle the remaining PCI errors.
131 */
132 status = __raw_readl(addr: hose->reg_base + SH4_PCIINT);
133 for (i = cmd = 0; i < ARRAY_SIZE(pci_interrupt_errors); i++) {
134 if (status & pci_interrupt_errors[i].mask) {
135 printk(KERN_DEBUG "PCI: %s, addr=%08lx\n",
136 pci_interrupt_errors[i].str, addr);
137 cmd |= pci_interrupt_errors[i].mask;
138 }
139 }
140 __raw_writel(val: cmd, addr: hose->reg_base + SH4_PCIINT);
141
142 return IRQ_HANDLED;
143}
144
145static irqreturn_t sh7780_pci_serr_irq(int irq, void *dev_id)
146{
147 struct pci_channel *hose = dev_id;
148
149 printk(KERN_DEBUG "PCI: system error received: ");
150 pcibios_report_status(PCI_STATUS_SIG_SYSTEM_ERROR, 1);
151 pr_cont("\n");
152
153 /* Deassert SERR */
154 __raw_writel(SH4_PCIINTM_SDIM, addr: hose->reg_base + SH4_PCIINTM);
155
156 /* Back off the IRQ for awhile */
157 disable_irq_nosync(irq);
158 hose->serr_timer.expires = jiffies + HZ;
159 add_timer(timer: &hose->serr_timer);
160
161 return IRQ_HANDLED;
162}
163
164static int __init sh7780_pci_setup_irqs(struct pci_channel *hose)
165{
166 int ret;
167
168 /* Clear out PCI arbiter IRQs */
169 __raw_writel(val: 0, addr: hose->reg_base + SH4_PCIAINT);
170
171 /* Clear all error conditions */
172 __raw_writew(PCI_STATUS_DETECTED_PARITY | \
173 PCI_STATUS_SIG_SYSTEM_ERROR | \
174 PCI_STATUS_REC_MASTER_ABORT | \
175 PCI_STATUS_REC_TARGET_ABORT | \
176 PCI_STATUS_SIG_TARGET_ABORT | \
177 PCI_STATUS_PARITY, addr: hose->reg_base + PCI_STATUS);
178
179 ret = request_irq(irq: hose->serr_irq, handler: sh7780_pci_serr_irq, flags: 0,
180 name: "PCI SERR interrupt", dev: hose);
181 if (unlikely(ret)) {
182 pr_err("PCI: Failed hooking SERR IRQ\n");
183 return ret;
184 }
185
186 /*
187 * The PCI ERR IRQ needs to be IRQF_SHARED since all of the power
188 * down IRQ vectors are routed through the ERR IRQ vector. We
189 * only request_irq() once as there is only a single masking
190 * source for multiple events.
191 */
192 ret = request_irq(irq: hose->err_irq, handler: sh7780_pci_err_irq, IRQF_SHARED,
193 name: "PCI ERR interrupt", dev: hose);
194 if (unlikely(ret)) {
195 free_irq(hose->serr_irq, hose);
196 return ret;
197 }
198
199 /* Unmask all of the arbiter IRQs. */
200 __raw_writel(SH4_PCIAINT_MBKN | SH4_PCIAINT_TBTO | SH4_PCIAINT_MBTO | \
201 SH4_PCIAINT_TABT | SH4_PCIAINT_MABT | SH4_PCIAINT_RDPE | \
202 SH4_PCIAINT_WDPE, addr: hose->reg_base + SH4_PCIAINTM);
203
204 /* Unmask all of the PCI IRQs */
205 __raw_writel(SH4_PCIINTM_TTADIM | SH4_PCIINTM_TMTOIM | \
206 SH4_PCIINTM_MDEIM | SH4_PCIINTM_APEDIM | \
207 SH4_PCIINTM_SDIM | SH4_PCIINTM_DPEITWM | \
208 SH4_PCIINTM_PEDITRM | SH4_PCIINTM_TADIMM | \
209 SH4_PCIINTM_MADIMM | SH4_PCIINTM_MWPDIM | \
210 SH4_PCIINTM_MRDPEIM, addr: hose->reg_base + SH4_PCIINTM);
211
212 return ret;
213}
214
215static inline void __init sh7780_pci_teardown_irqs(struct pci_channel *hose)
216{
217 free_irq(hose->err_irq, hose);
218 free_irq(hose->serr_irq, hose);
219}
220
221static void __init sh7780_pci66_init(struct pci_channel *hose)
222{
223 unsigned int tmp;
224
225 if (!pci_is_66mhz_capable(hose, 0, 0))
226 return;
227
228 /* Enable register access */
229 tmp = __raw_readl(addr: hose->reg_base + SH4_PCICR);
230 tmp |= SH4_PCICR_PREFIX;
231 __raw_writel(val: tmp, addr: hose->reg_base + SH4_PCICR);
232
233 /* Enable 66MHz operation */
234 tmp = __raw_readw(addr: hose->reg_base + PCI_STATUS);
235 tmp |= PCI_STATUS_66MHZ;
236 __raw_writew(val: tmp, addr: hose->reg_base + PCI_STATUS);
237
238 /* Done */
239 tmp = __raw_readl(addr: hose->reg_base + SH4_PCICR);
240 tmp |= SH4_PCICR_PREFIX | SH4_PCICR_CFIN;
241 __raw_writel(val: tmp, addr: hose->reg_base + SH4_PCICR);
242}
243
244static int __init sh7780_pci_init(void)
245{
246 struct pci_channel *chan = &sh7780_pci_controller;
247 phys_addr_t memphys;
248 size_t memsize;
249 unsigned int id;
250 const char *type;
251 int ret, i;
252
253 pr_notice("PCI: Starting initialization.\n");
254
255 chan->reg_base = 0xfe040000;
256
257 /* Enable CPU access to the PCIC registers. */
258 __raw_writel(val: PCIECR_ENBL, addr: PCIECR);
259
260 /* Reset */
261 __raw_writel(SH4_PCICR_PREFIX | SH4_PCICR_PRST | PCICR_ENDIANNESS,
262 addr: chan->reg_base + SH4_PCICR);
263
264 /*
265 * Wait for it to come back up. The spec says to allow for up to
266 * 1 second after toggling the reset pin, but in practice 100ms
267 * is more than enough.
268 */
269 mdelay(100);
270
271 id = __raw_readw(addr: chan->reg_base + PCI_VENDOR_ID);
272 if (id != PCI_VENDOR_ID_RENESAS) {
273 pr_err("PCI: Unknown vendor ID 0x%04x.\n", id);
274 return -ENODEV;
275 }
276
277 id = __raw_readw(addr: chan->reg_base + PCI_DEVICE_ID);
278 type = (id == PCI_DEVICE_ID_RENESAS_SH7763) ? "SH7763" :
279 (id == PCI_DEVICE_ID_RENESAS_SH7780) ? "SH7780" :
280 (id == PCI_DEVICE_ID_RENESAS_SH7781) ? "SH7781" :
281 (id == PCI_DEVICE_ID_RENESAS_SH7785) ? "SH7785" :
282 NULL;
283 if (unlikely(!type)) {
284 pr_err("PCI: Found an unsupported Renesas host controller, device id 0x%04x.\n",
285 id);
286 return -EINVAL;
287 }
288
289 pr_notice("PCI: Found a Renesas %s host controller, revision %d.\n",
290 type, __raw_readb(chan->reg_base + PCI_REVISION_ID));
291
292 /*
293 * Now throw it in to register initialization mode and
294 * start the real work.
295 */
296 __raw_writel(SH4_PCICR_PREFIX | PCICR_ENDIANNESS,
297 addr: chan->reg_base + SH4_PCICR);
298
299 memphys = __pa(memory_start);
300 memsize = roundup_pow_of_two(memory_end - memory_start);
301
302 /*
303 * If there's more than 512MB of memory, we need to roll over to
304 * LAR1/LSR1.
305 */
306 if (memsize > SZ_512M) {
307 __raw_writel(val: memphys + SZ_512M, addr: chan->reg_base + SH4_PCILAR1);
308 __raw_writel(val: (((memsize - SZ_512M) - SZ_1M) & 0x1ff00000) | 1,
309 addr: chan->reg_base + SH4_PCILSR1);
310 memsize = SZ_512M;
311 } else {
312 /*
313 * Otherwise just zero it out and disable it.
314 */
315 __raw_writel(val: 0, addr: chan->reg_base + SH4_PCILAR1);
316 __raw_writel(val: 0, addr: chan->reg_base + SH4_PCILSR1);
317 }
318
319 /*
320 * LAR0/LSR0 covers up to the first 512MB, which is enough to
321 * cover all of lowmem on most platforms.
322 */
323 __raw_writel(val: memphys, addr: chan->reg_base + SH4_PCILAR0);
324 __raw_writel(val: ((memsize - SZ_1M) & 0x1ff00000) | 1,
325 addr: chan->reg_base + SH4_PCILSR0);
326
327 /*
328 * Hook up the ERR and SERR IRQs.
329 */
330 ret = sh7780_pci_setup_irqs(hose: chan);
331 if (unlikely(ret))
332 return ret;
333
334 /*
335 * Disable the cache snoop controller for non-coherent DMA.
336 */
337 __raw_writel(val: 0, addr: chan->reg_base + SH7780_PCICSCR0);
338 __raw_writel(val: 0, addr: chan->reg_base + SH7780_PCICSAR0);
339 __raw_writel(val: 0, addr: chan->reg_base + SH7780_PCICSCR1);
340 __raw_writel(val: 0, addr: chan->reg_base + SH7780_PCICSAR1);
341
342 /*
343 * Setup the memory BARs
344 */
345 for (i = 1; i < chan->nr_resources; i++) {
346 struct resource *res = chan->resources + i;
347 resource_size_t size;
348
349 if (unlikely(res->flags & IORESOURCE_IO))
350 continue;
351
352 /*
353 * Make sure we're in the right physical addressing mode
354 * for dealing with the resource.
355 */
356 if ((res->flags & IORESOURCE_MEM_32BIT) && __in_29bit_mode()) {
357 chan->nr_resources--;
358 continue;
359 }
360
361 size = resource_size(res);
362
363 /*
364 * The MBMR mask is calculated in units of 256kB, which
365 * keeps things pretty simple.
366 */
367 __raw_writel(val: ((roundup_pow_of_two(size) / SZ_256K) - 1) << 18,
368 addr: chan->reg_base + SH7780_PCIMBMR(i - 1));
369 __raw_writel(val: res->start, addr: chan->reg_base + SH7780_PCIMBR(i - 1));
370 }
371
372 /*
373 * And I/O.
374 */
375 __raw_writel(val: 0, addr: chan->reg_base + PCI_BASE_ADDRESS_0);
376 __raw_writel(val: 0, addr: chan->reg_base + SH7780_PCIIOBR);
377 __raw_writel(val: 0, addr: chan->reg_base + SH7780_PCIIOBMR);
378
379 __raw_writew(PCI_COMMAND_SERR | PCI_COMMAND_WAIT | \
380 PCI_COMMAND_PARITY | PCI_COMMAND_MASTER | \
381 PCI_COMMAND_MEMORY, addr: chan->reg_base + PCI_COMMAND);
382
383 /*
384 * Initialization mode complete, release the control register and
385 * enable round robin mode to stop device overruns/starvation.
386 */
387 __raw_writel(SH4_PCICR_PREFIX | SH4_PCICR_CFIN | SH4_PCICR_FTO |
388 PCICR_ENDIANNESS,
389 addr: chan->reg_base + SH4_PCICR);
390
391 ret = register_pci_controller(chan);
392 if (unlikely(ret))
393 goto err;
394
395 sh7780_pci66_init(hose: chan);
396
397 pr_notice("PCI: Running at %dMHz.\n",
398 (__raw_readw(chan->reg_base + PCI_STATUS) & PCI_STATUS_66MHZ)
399 ? 66 : 33);
400
401 return 0;
402
403err:
404 sh7780_pci_teardown_irqs(hose: chan);
405 return ret;
406}
407arch_initcall(sh7780_pci_init);
408

source code of linux/arch/sh/drivers/pci/pci-sh7780.c