1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * arch/arm/plat-iop/pci.c
4 *
5 * PCI support for the Intel IOP32X and IOP33X processors
6 *
7 * Author: Rory Bolt <rorybolt@pacbell.net>
8 * Copyright (C) 2002 Rory Bolt
9 */
10
11 #include <linux/kernel.h>
12 #include <linux/pci.h>
13 #include <linux/slab.h>
14 #include <linux/mm.h>
15 #include <linux/init.h>
16 #include <linux/ioport.h>
17 #include <linux/io.h>
18 #include <asm/irq.h>
19 #include <asm/signal.h>
20 #include <asm/mach/pci.h>
21 #include "hardware.h"
22 #include "iop3xx.h"
23
24 // #define DEBUG
25
26 #ifdef DEBUG
27 #define DBG(x...) printk(x)
28 #else
29 #define DBG(x...) do { } while (0)
30 #endif
31
32 /*
33 * This routine builds either a type0 or type1 configuration command. If the
34 * bus is on the 803xx then a type0 made, else a type1 is created.
35 */
iop3xx_cfg_address(struct pci_bus * bus,int devfn,int where)36 static u32 iop3xx_cfg_address(struct pci_bus *bus, int devfn, int where)
37 {
38 struct pci_sys_data *sys = bus->sysdata;
39 u32 addr;
40
41 if (sys->busnr == bus->number)
42 addr = 1 << (PCI_SLOT(devfn) + 16) | (PCI_SLOT(devfn) << 11);
43 else
44 addr = bus->number << 16 | PCI_SLOT(devfn) << 11 | 1;
45
46 addr |= PCI_FUNC(devfn) << 8 | (where & ~3);
47
48 return addr;
49 }
50
51 /*
52 * This routine checks the status of the last configuration cycle. If an error
53 * was detected it returns a 1, else it returns a 0. The errors being checked
54 * are parity, master abort, target abort (master and target). These types of
55 * errors occur during a config cycle where there is no device, like during
56 * the discovery stage.
57 */
iop3xx_pci_status(void)58 static int iop3xx_pci_status(void)
59 {
60 unsigned int status;
61 int ret = 0;
62
63 /*
64 * Check the status registers.
65 */
66 status = *IOP3XX_ATUSR;
67 if (status & 0xf900) {
68 DBG("\t\t\tPCI: P0 - status = 0x%08x\n", status);
69 *IOP3XX_ATUSR = status & 0xf900;
70 ret = 1;
71 }
72
73 status = *IOP3XX_ATUISR;
74 if (status & 0x679f) {
75 DBG("\t\t\tPCI: P1 - status = 0x%08x\n", status);
76 *IOP3XX_ATUISR = status & 0x679f;
77 ret = 1;
78 }
79
80 return ret;
81 }
82
83 /*
84 * Simply write the address register and read the configuration
85 * data. Note that the 4 nops ensure that we are able to handle
86 * a delayed abort (in theory.)
87 */
iop3xx_read(unsigned long addr)88 static u32 iop3xx_read(unsigned long addr)
89 {
90 u32 val;
91
92 __asm__ __volatile__(
93 "str %1, [%2]\n\t"
94 "ldr %0, [%3]\n\t"
95 "nop\n\t"
96 "nop\n\t"
97 "nop\n\t"
98 "nop\n\t"
99 : "=r" (val)
100 : "r" (addr), "r" (IOP3XX_OCCAR), "r" (IOP3XX_OCCDR));
101
102 return val;
103 }
104
105 /*
106 * The read routines must check the error status of the last configuration
107 * cycle. If there was an error, the routine returns all hex f's.
108 */
109 static int
iop3xx_read_config(struct pci_bus * bus,unsigned int devfn,int where,int size,u32 * value)110 iop3xx_read_config(struct pci_bus *bus, unsigned int devfn, int where,
111 int size, u32 *value)
112 {
113 unsigned long addr = iop3xx_cfg_address(bus, devfn, where);
114 u32 val = iop3xx_read(addr) >> ((where & 3) * 8);
115
116 if (iop3xx_pci_status())
117 val = 0xffffffff;
118
119 *value = val;
120
121 return PCIBIOS_SUCCESSFUL;
122 }
123
124 static int
iop3xx_write_config(struct pci_bus * bus,unsigned int devfn,int where,int size,u32 value)125 iop3xx_write_config(struct pci_bus *bus, unsigned int devfn, int where,
126 int size, u32 value)
127 {
128 unsigned long addr = iop3xx_cfg_address(bus, devfn, where);
129 u32 val;
130
131 if (size != 4) {
132 val = iop3xx_read(addr);
133 if (iop3xx_pci_status())
134 return PCIBIOS_SUCCESSFUL;
135
136 where = (where & 3) * 8;
137
138 if (size == 1)
139 val &= ~(0xff << where);
140 else
141 val &= ~(0xffff << where);
142
143 *IOP3XX_OCCDR = val | value << where;
144 } else {
145 asm volatile(
146 "str %1, [%2]\n\t"
147 "str %0, [%3]\n\t"
148 "nop\n\t"
149 "nop\n\t"
150 "nop\n\t"
151 "nop\n\t"
152 :
153 : "r" (value), "r" (addr),
154 "r" (IOP3XX_OCCAR), "r" (IOP3XX_OCCDR));
155 }
156
157 return PCIBIOS_SUCCESSFUL;
158 }
159
160 struct pci_ops iop3xx_ops = {
161 .read = iop3xx_read_config,
162 .write = iop3xx_write_config,
163 };
164
165 /*
166 * When a PCI device does not exist during config cycles, the 80200 gets a
167 * bus error instead of returning 0xffffffff. This handler simply returns.
168 */
169 static int
iop3xx_pci_abort(unsigned long addr,unsigned int fsr,struct pt_regs * regs)170 iop3xx_pci_abort(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
171 {
172 DBG("PCI abort: address = 0x%08lx fsr = 0x%03x PC = 0x%08lx LR = 0x%08lx\n",
173 addr, fsr, regs->ARM_pc, regs->ARM_lr);
174
175 /*
176 * If it was an imprecise abort, then we need to correct the
177 * return address to be _after_ the instruction.
178 */
179 if (fsr & (1 << 10))
180 regs->ARM_pc += 4;
181
182 return 0;
183 }
184
iop3xx_pci_setup(int nr,struct pci_sys_data * sys)185 int iop3xx_pci_setup(int nr, struct pci_sys_data *sys)
186 {
187 struct resource *res;
188 struct resource realio;
189
190 if (nr != 0)
191 return 0;
192
193 res = kzalloc(sizeof(struct resource), GFP_KERNEL);
194 if (!res)
195 panic("PCI: unable to alloc resources");
196
197 res->start = IOP3XX_PCI_LOWER_MEM_PA;
198 res->end = IOP3XX_PCI_LOWER_MEM_PA + IOP3XX_PCI_MEM_WINDOW_SIZE - 1;
199 res->name = "IOP3XX PCI Memory Space";
200 res->flags = IORESOURCE_MEM;
201 request_resource(&iomem_resource, res);
202
203 /*
204 * Use whatever translation is already setup.
205 */
206 sys->mem_offset = IOP3XX_PCI_LOWER_MEM_PA - *IOP3XX_OMWTVR0;
207
208 pci_add_resource_offset(&sys->resources, res, sys->mem_offset);
209
210 realio.start = 0;
211 realio.end = realio.start + SZ_64K - 1;
212 pci_remap_iospace(&realio, IOP3XX_PCI_LOWER_IO_PA);
213
214 return 1;
215 }
216
iop3xx_atu_setup(void)217 void __init iop3xx_atu_setup(void)
218 {
219 /* BAR 0 ( Disabled ) */
220 *IOP3XX_IAUBAR0 = 0x0;
221 *IOP3XX_IABAR0 = 0x0;
222 *IOP3XX_IATVR0 = 0x0;
223 *IOP3XX_IALR0 = 0x0;
224
225 /* BAR 1 ( Disabled ) */
226 *IOP3XX_IAUBAR1 = 0x0;
227 *IOP3XX_IABAR1 = 0x0;
228 *IOP3XX_IALR1 = 0x0;
229
230 /* BAR 2 (1:1 mapping with Physical RAM) */
231 /* Set limit and enable */
232 *IOP3XX_IALR2 = ~((u32)IOP3XX_MAX_RAM_SIZE - 1) & ~0x1;
233 *IOP3XX_IAUBAR2 = 0x0;
234
235 /* Align the inbound bar with the base of memory */
236 *IOP3XX_IABAR2 = PHYS_OFFSET |
237 PCI_BASE_ADDRESS_MEM_TYPE_64 |
238 PCI_BASE_ADDRESS_MEM_PREFETCH;
239
240 *IOP3XX_IATVR2 = PHYS_OFFSET;
241
242 /* Outbound window 0 */
243 *IOP3XX_OMWTVR0 = IOP3XX_PCI_LOWER_MEM_BA;
244 *IOP3XX_OUMWTVR0 = 0;
245
246 /* Outbound window 1 */
247 *IOP3XX_OMWTVR1 = IOP3XX_PCI_LOWER_MEM_BA +
248 IOP3XX_PCI_MEM_WINDOW_SIZE / 2;
249 *IOP3XX_OUMWTVR1 = 0;
250
251 /* BAR 3 ( Disabled ) */
252 *IOP3XX_IAUBAR3 = 0x0;
253 *IOP3XX_IABAR3 = 0x0;
254 *IOP3XX_IATVR3 = 0x0;
255 *IOP3XX_IALR3 = 0x0;
256
257 /* Setup the I/O Bar
258 */
259 *IOP3XX_OIOWTVR = IOP3XX_PCI_LOWER_IO_BA;
260
261 /* Enable inbound and outbound cycles
262 */
263 *IOP3XX_ATUCMD |= PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER |
264 PCI_COMMAND_PARITY | PCI_COMMAND_SERR;
265 *IOP3XX_ATUCR |= IOP3XX_ATUCR_OUT_EN;
266 }
267
iop3xx_atu_disable(void)268 void __init iop3xx_atu_disable(void)
269 {
270 *IOP3XX_ATUCMD = 0;
271 *IOP3XX_ATUCR = 0;
272
273 /* wait for cycles to quiesce */
274 while (*IOP3XX_PCSR & (IOP3XX_PCSR_OUT_Q_BUSY |
275 IOP3XX_PCSR_IN_Q_BUSY))
276 cpu_relax();
277
278 /* BAR 0 ( Disabled ) */
279 *IOP3XX_IAUBAR0 = 0x0;
280 *IOP3XX_IABAR0 = 0x0;
281 *IOP3XX_IATVR0 = 0x0;
282 *IOP3XX_IALR0 = 0x0;
283
284 /* BAR 1 ( Disabled ) */
285 *IOP3XX_IAUBAR1 = 0x0;
286 *IOP3XX_IABAR1 = 0x0;
287 *IOP3XX_IALR1 = 0x0;
288
289 /* BAR 2 ( Disabled ) */
290 *IOP3XX_IAUBAR2 = 0x0;
291 *IOP3XX_IABAR2 = 0x0;
292 *IOP3XX_IATVR2 = 0x0;
293 *IOP3XX_IALR2 = 0x0;
294
295 /* BAR 3 ( Disabled ) */
296 *IOP3XX_IAUBAR3 = 0x0;
297 *IOP3XX_IABAR3 = 0x0;
298 *IOP3XX_IATVR3 = 0x0;
299 *IOP3XX_IALR3 = 0x0;
300
301 /* Clear the outbound windows */
302 *IOP3XX_OIOWTVR = 0;
303
304 /* Outbound window 0 */
305 *IOP3XX_OMWTVR0 = 0;
306 *IOP3XX_OUMWTVR0 = 0;
307
308 /* Outbound window 1 */
309 *IOP3XX_OMWTVR1 = 0;
310 *IOP3XX_OUMWTVR1 = 0;
311 }
312
313 /* Flag to determine whether the ATU is initialized and the PCI bus scanned */
314 int init_atu;
315
iop3xx_get_init_atu(void)316 int iop3xx_get_init_atu(void) {
317 /* check if default has been overridden */
318 if (init_atu != IOP3XX_INIT_ATU_DEFAULT)
319 return init_atu;
320 else
321 return IOP3XX_INIT_ATU_DISABLE;
322 }
323
iop3xx_atu_debug(void)324 static void __init iop3xx_atu_debug(void)
325 {
326 DBG("PCI: Intel IOP3xx PCI init.\n");
327 DBG("PCI: Outbound memory window 0: PCI 0x%08x%08x\n",
328 *IOP3XX_OUMWTVR0, *IOP3XX_OMWTVR0);
329 DBG("PCI: Outbound memory window 1: PCI 0x%08x%08x\n",
330 *IOP3XX_OUMWTVR1, *IOP3XX_OMWTVR1);
331 DBG("PCI: Outbound IO window: PCI 0x%08x\n",
332 *IOP3XX_OIOWTVR);
333
334 DBG("PCI: Inbound memory window 0: PCI 0x%08x%08x 0x%08x -> 0x%08x\n",
335 *IOP3XX_IAUBAR0, *IOP3XX_IABAR0, *IOP3XX_IALR0, *IOP3XX_IATVR0);
336 DBG("PCI: Inbound memory window 1: PCI 0x%08x%08x 0x%08x\n",
337 *IOP3XX_IAUBAR1, *IOP3XX_IABAR1, *IOP3XX_IALR1);
338 DBG("PCI: Inbound memory window 2: PCI 0x%08x%08x 0x%08x -> 0x%08x\n",
339 *IOP3XX_IAUBAR2, *IOP3XX_IABAR2, *IOP3XX_IALR2, *IOP3XX_IATVR2);
340 DBG("PCI: Inbound memory window 3: PCI 0x%08x%08x 0x%08x -> 0x%08x\n",
341 *IOP3XX_IAUBAR3, *IOP3XX_IABAR3, *IOP3XX_IALR3, *IOP3XX_IATVR3);
342
343 DBG("PCI: Expansion ROM window: PCI 0x%08x%08x 0x%08x -> 0x%08x\n",
344 0, *IOP3XX_ERBAR, *IOP3XX_ERLR, *IOP3XX_ERTVR);
345
346 DBG("ATU: IOP3XX_ATUCMD=0x%04x\n", *IOP3XX_ATUCMD);
347 DBG("ATU: IOP3XX_ATUCR=0x%08x\n", *IOP3XX_ATUCR);
348
349 hook_fault_code(16+6, iop3xx_pci_abort, SIGBUS, 0, "imprecise external abort");
350 }
351
352 /* for platforms that might be host-bus-adapters */
iop3xx_pci_preinit_cond(void)353 void __init iop3xx_pci_preinit_cond(void)
354 {
355 if (iop3xx_get_init_atu() == IOP3XX_INIT_ATU_ENABLE) {
356 iop3xx_atu_disable();
357 iop3xx_atu_setup();
358 iop3xx_atu_debug();
359 }
360 }
361
iop3xx_pci_preinit(void)362 void __init iop3xx_pci_preinit(void)
363 {
364 pcibios_min_mem = 0;
365
366 iop3xx_atu_disable();
367 iop3xx_atu_setup();
368 iop3xx_atu_debug();
369 }
370
371 /* allow init_atu to be user overridden */
iop3xx_init_atu_setup(char * str)372 static int __init iop3xx_init_atu_setup(char *str)
373 {
374 init_atu = IOP3XX_INIT_ATU_DEFAULT;
375 if (str) {
376 while (*str != '\0') {
377 switch (*str) {
378 case 'y':
379 case 'Y':
380 init_atu = IOP3XX_INIT_ATU_ENABLE;
381 break;
382 case 'n':
383 case 'N':
384 init_atu = IOP3XX_INIT_ATU_DISABLE;
385 break;
386 case ',':
387 case '=':
388 break;
389 default:
390 printk(KERN_DEBUG "\"%s\" malformed at "
391 "character: \'%c\'",
392 __func__,
393 *str);
394 *(str + 1) = '\0';
395 }
396 str++;
397 }
398 }
399
400 return 1;
401 }
402
403 __setup("iop3xx_init_atu", iop3xx_init_atu_setup);
404
405