1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * linux/arch/arm/kernel/dec21285.c: PCI functions for DC21285
4 *
5 * Copyright (C) 1998-2001 Russell King
6 * Copyright (C) 1998-2000 Phil Blundell
7 */
8#include <linux/dma-map-ops.h>
9#include <linux/kernel.h>
10#include <linux/pci.h>
11#include <linux/interrupt.h>
12#include <linux/mm.h>
13#include <linux/slab.h>
14#include <linux/init.h>
15#include <linux/ioport.h>
16#include <linux/irq.h>
17#include <linux/io.h>
18#include <linux/spinlock.h>
19
20#include <asm/irq.h>
21#include <asm/mach/pci.h>
22#include <asm/hardware/dec21285.h>
23
24#define MAX_SLOTS 21
25
26#define PCICMD_ABORT ((PCI_STATUS_REC_MASTER_ABORT| \
27 PCI_STATUS_REC_TARGET_ABORT)<<16)
28
29#define PCICMD_ERROR_BITS ((PCI_STATUS_DETECTED_PARITY | \
30 PCI_STATUS_REC_MASTER_ABORT | \
31 PCI_STATUS_REC_TARGET_ABORT | \
32 PCI_STATUS_PARITY) << 16)
33
34extern int setup_arm_irq(int, struct irqaction *);
35
36static unsigned long
37dc21285_base_address(struct pci_bus *bus, unsigned int devfn)
38{
39 unsigned long addr = 0;
40
41 if (bus->number == 0) {
42 if (PCI_SLOT(devfn) == 0)
43 /*
44 * For devfn 0, point at the 21285
45 */
46 addr = ARMCSR_BASE;
47 else {
48 devfn -= 1 << 3;
49
50 if (devfn < PCI_DEVFN(MAX_SLOTS, 0))
51 addr = PCICFG0_BASE | 0xc00000 | (devfn << 8);
52 }
53 } else
54 addr = PCICFG1_BASE | (bus->number << 16) | (devfn << 8);
55
56 return addr;
57}
58
59static int
60dc21285_read_config(struct pci_bus *bus, unsigned int devfn, int where,
61 int size, u32 *value)
62{
63 unsigned long addr = dc21285_base_address(bus, devfn);
64 u32 v = 0xffffffff;
65
66 if (addr)
67 switch (size) {
68 case 1:
69 asm volatile("ldrb %0, [%1, %2]"
70 : "=r" (v) : "r" (addr), "r" (where) : "cc");
71 break;
72 case 2:
73 asm volatile("ldrh %0, [%1, %2]"
74 : "=r" (v) : "r" (addr), "r" (where) : "cc");
75 break;
76 case 4:
77 asm volatile("ldr %0, [%1, %2]"
78 : "=r" (v) : "r" (addr), "r" (where) : "cc");
79 break;
80 }
81
82 *value = v;
83
84 v = *CSR_PCICMD;
85 if (v & PCICMD_ABORT) {
86 *CSR_PCICMD = v & (0xffff|PCICMD_ABORT);
87 return -1;
88 }
89
90 return PCIBIOS_SUCCESSFUL;
91}
92
93static int
94dc21285_write_config(struct pci_bus *bus, unsigned int devfn, int where,
95 int size, u32 value)
96{
97 unsigned long addr = dc21285_base_address(bus, devfn);
98 u32 v;
99
100 if (addr)
101 switch (size) {
102 case 1:
103 asm volatile("strb %0, [%1, %2]"
104 : : "r" (value), "r" (addr), "r" (where)
105 : "cc");
106 break;
107 case 2:
108 asm volatile("strh %0, [%1, %2]"
109 : : "r" (value), "r" (addr), "r" (where)
110 : "cc");
111 break;
112 case 4:
113 asm volatile("str %0, [%1, %2]"
114 : : "r" (value), "r" (addr), "r" (where)
115 : "cc");
116 break;
117 }
118
119 v = *CSR_PCICMD;
120 if (v & PCICMD_ABORT) {
121 *CSR_PCICMD = v & (0xffff|PCICMD_ABORT);
122 return -1;
123 }
124
125 return PCIBIOS_SUCCESSFUL;
126}
127
128struct pci_ops dc21285_ops = {
129 .read = dc21285_read_config,
130 .write = dc21285_write_config,
131};
132
133static struct timer_list serr_timer;
134static struct timer_list perr_timer;
135
136static void dc21285_enable_error(struct timer_list *timer)
137{
138 del_timer(timer);
139
140 if (timer == &serr_timer)
141 enable_irq(irq: IRQ_PCI_SERR);
142 else if (timer == &perr_timer)
143 enable_irq(irq: IRQ_PCI_PERR);
144}
145
146/*
147 * Warn on PCI errors.
148 */
149static irqreturn_t dc21285_abort_irq(int irq, void *dev_id)
150{
151 unsigned int cmd;
152 unsigned int status;
153
154 cmd = *CSR_PCICMD;
155 status = cmd >> 16;
156 cmd = cmd & 0xffff;
157
158 if (status & PCI_STATUS_REC_MASTER_ABORT) {
159 printk(KERN_DEBUG "PCI: master abort, pc=0x%08lx\n",
160 instruction_pointer(get_irq_regs()));
161 cmd |= PCI_STATUS_REC_MASTER_ABORT << 16;
162 }
163
164 if (status & PCI_STATUS_REC_TARGET_ABORT) {
165 printk(KERN_DEBUG "PCI: target abort: ");
166 pcibios_report_status(PCI_STATUS_REC_MASTER_ABORT |
167 PCI_STATUS_SIG_TARGET_ABORT |
168 PCI_STATUS_REC_TARGET_ABORT, 1);
169 printk("\n");
170
171 cmd |= PCI_STATUS_REC_TARGET_ABORT << 16;
172 }
173
174 *CSR_PCICMD = cmd;
175
176 return IRQ_HANDLED;
177}
178
179static irqreturn_t dc21285_serr_irq(int irq, void *dev_id)
180{
181 struct timer_list *timer = dev_id;
182 unsigned int cntl;
183
184 printk(KERN_DEBUG "PCI: system error received: ");
185 pcibios_report_status(PCI_STATUS_SIG_SYSTEM_ERROR, 1);
186 printk("\n");
187
188 cntl = *CSR_SA110_CNTL & 0xffffdf07;
189 *CSR_SA110_CNTL = cntl | SA110_CNTL_RXSERR;
190
191 /*
192 * back off this interrupt
193 */
194 disable_irq(irq);
195 timer->expires = jiffies + HZ;
196 add_timer(timer);
197
198 return IRQ_HANDLED;
199}
200
201static irqreturn_t dc21285_discard_irq(int irq, void *dev_id)
202{
203 printk(KERN_DEBUG "PCI: discard timer expired\n");
204 *CSR_SA110_CNTL &= 0xffffde07;
205
206 return IRQ_HANDLED;
207}
208
209static irqreturn_t dc21285_dparity_irq(int irq, void *dev_id)
210{
211 unsigned int cmd;
212
213 printk(KERN_DEBUG "PCI: data parity error detected: ");
214 pcibios_report_status(PCI_STATUS_PARITY | PCI_STATUS_DETECTED_PARITY, 1);
215 printk("\n");
216
217 cmd = *CSR_PCICMD & 0xffff;
218 *CSR_PCICMD = cmd | 1 << 24;
219
220 return IRQ_HANDLED;
221}
222
223static irqreturn_t dc21285_parity_irq(int irq, void *dev_id)
224{
225 struct timer_list *timer = dev_id;
226 unsigned int cmd;
227
228 printk(KERN_DEBUG "PCI: parity error detected: ");
229 pcibios_report_status(PCI_STATUS_PARITY | PCI_STATUS_DETECTED_PARITY, 1);
230 printk("\n");
231
232 cmd = *CSR_PCICMD & 0xffff;
233 *CSR_PCICMD = cmd | 1 << 31;
234
235 /*
236 * back off this interrupt
237 */
238 disable_irq(irq);
239 timer->expires = jiffies + HZ;
240 add_timer(timer);
241
242 return IRQ_HANDLED;
243}
244
245static int dc21285_pci_bus_notifier(struct notifier_block *nb,
246 unsigned long action,
247 void *data)
248{
249 if (action != BUS_NOTIFY_ADD_DEVICE)
250 return NOTIFY_DONE;
251
252 dma_direct_set_offset(dev: data, cpu_start: PHYS_OFFSET, dma_start: BUS_OFFSET, SZ_256M);
253
254 return NOTIFY_OK;
255}
256
257static struct notifier_block dc21285_pci_bus_nb = {
258 .notifier_call = dc21285_pci_bus_notifier,
259};
260
261int __init dc21285_setup(int nr, struct pci_sys_data *sys)
262{
263 struct resource *res;
264
265 res = kcalloc(n: 2, size: sizeof(struct resource), GFP_KERNEL);
266 if (!res) {
267 printk("out of memory for root bus resources");
268 return 0;
269 }
270
271 res[0].flags = IORESOURCE_MEM;
272 res[0].name = "Footbridge non-prefetch";
273 res[1].flags = IORESOURCE_MEM | IORESOURCE_PREFETCH;
274 res[1].name = "Footbridge prefetch";
275
276 allocate_resource(root: &iomem_resource, new: &res[1], size: 0x20000000,
277 min: 0xa0000000, max: 0xffffffff, align: 0x20000000, NULL, NULL);
278 allocate_resource(root: &iomem_resource, new: &res[0], size: 0x40000000,
279 min: 0x80000000, max: 0xffffffff, align: 0x40000000, NULL, NULL);
280
281 sys->mem_offset = DC21285_PCI_MEM;
282
283 pci_add_resource_offset(resources: &sys->resources, res: &res[0], offset: sys->mem_offset);
284 pci_add_resource_offset(resources: &sys->resources, res: &res[1], offset: sys->mem_offset);
285
286 bus_register_notifier(bus: &pci_bus_type, nb: &dc21285_pci_bus_nb);
287
288 return 1;
289}
290
291#define dc21285_request_irq(_a, _b, _c, _d, _e) \
292 WARN_ON(request_irq(_a, _b, _c, _d, _e) < 0)
293
294void __init dc21285_preinit(void)
295{
296 unsigned int mem_size, mem_mask;
297
298 pcibios_min_mem = 0x81000000;
299
300 mem_size = (unsigned int)high_memory - PAGE_OFFSET;
301 for (mem_mask = 0x00100000; mem_mask < 0x10000000; mem_mask <<= 1)
302 if (mem_mask >= mem_size)
303 break;
304
305 /*
306 * These registers need to be set up whether we're the
307 * central function or not.
308 */
309 *CSR_SDRAMBASEMASK = (mem_mask - 1) & 0x0ffc0000;
310 *CSR_SDRAMBASEOFFSET = 0;
311 *CSR_ROMBASEMASK = 0x80000000;
312 *CSR_CSRBASEMASK = 0;
313 *CSR_CSRBASEOFFSET = 0;
314 *CSR_PCIADDR_EXTN = 0;
315
316 printk(KERN_INFO "PCI: DC21285 footbridge, revision %02lX, in "
317 "central function mode\n", *CSR_CLASSREV & 0xff);
318
319 /*
320 * Clear any existing errors - we aren't
321 * interested in historical data...
322 */
323 *CSR_SA110_CNTL = (*CSR_SA110_CNTL & 0xffffde07) | SA110_CNTL_RXSERR;
324 *CSR_PCICMD = (*CSR_PCICMD & 0xffff) | PCICMD_ERROR_BITS;
325
326 timer_setup(&serr_timer, dc21285_enable_error, 0);
327 timer_setup(&perr_timer, dc21285_enable_error, 0);
328
329 /*
330 * We don't care if these fail.
331 */
332 dc21285_request_irq(IRQ_PCI_SERR, dc21285_serr_irq, 0,
333 "PCI system error", &serr_timer);
334 dc21285_request_irq(IRQ_PCI_PERR, dc21285_parity_irq, 0,
335 "PCI parity error", &perr_timer);
336 dc21285_request_irq(IRQ_PCI_ABORT, dc21285_abort_irq, 0,
337 "PCI abort", NULL);
338 dc21285_request_irq(IRQ_DISCARD_TIMER, dc21285_discard_irq, 0,
339 "Discard timer", NULL);
340 dc21285_request_irq(IRQ_PCI_DPERR, dc21285_dparity_irq, 0,
341 "PCI data parity", NULL);
342
343 /*
344 * Map our SDRAM at a known address in PCI space, just in case
345 * the firmware had other ideas. Using a nonzero base is
346 * necessary, since some VGA cards forcefully use PCI addresses
347 * in the range 0x000a0000 to 0x000c0000. (eg, S3 cards).
348 */
349 *CSR_PCICSRBASE = 0xf4000000;
350 *CSR_PCICSRIOBASE = 0;
351 *CSR_PCISDRAMBASE = BUS_OFFSET;
352 *CSR_PCIROMBASE = 0;
353 *CSR_PCICMD = PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER |
354 PCI_COMMAND_INVALIDATE | PCICMD_ERROR_BITS;
355}
356
357void __init dc21285_postinit(void)
358{
359 register_isa_ports(DC21285_PCI_MEM, DC21285_PCI_IO, 0);
360}
361

source code of linux/arch/arm/mach-footbridge/dc21285.c