1 // SPDX-License-Identifier: GPL-2.0-only
3 * linux/arch/arm/kernel/dec21285.c: PCI functions for DC21285
5 * Copyright (C) 1998-2001 Russell King
6 * Copyright (C) 1998-2000 Phil Blundell
8 #include <linux/kernel.h>
10 #include <linux/interrupt.h>
12 #include <linux/slab.h>
13 #include <linux/init.h>
14 #include <linux/ioport.h>
15 #include <linux/irq.h>
17 #include <linux/spinlock.h>
20 #include <asm/mach/pci.h>
21 #include <asm/hardware/dec21285.h>
25 #define PCICMD_ABORT ((PCI_STATUS_REC_MASTER_ABORT| \
26 PCI_STATUS_REC_TARGET_ABORT)<<16)
28 #define PCICMD_ERROR_BITS ((PCI_STATUS_DETECTED_PARITY | \
29 PCI_STATUS_REC_MASTER_ABORT | \
30 PCI_STATUS_REC_TARGET_ABORT | \
31 PCI_STATUS_PARITY) << 16)
33 extern int setup_arm_irq(int, struct irqaction *);
34 extern void pcibios_report_status(u_int status_mask, int warn);
37 dc21285_base_address(struct pci_bus *bus, unsigned int devfn)
39 unsigned long addr = 0;
41 if (bus->number == 0) {
42 if (PCI_SLOT(devfn) == 0)
44 * For devfn 0, point at the 21285
50 if (devfn < PCI_DEVFN(MAX_SLOTS, 0))
51 addr = PCICFG0_BASE | 0xc00000 | (devfn << 8);
54 addr = PCICFG1_BASE | (bus->number << 16) | (devfn << 8);
60 dc21285_read_config(struct pci_bus *bus, unsigned int devfn, int where,
63 unsigned long addr = dc21285_base_address(bus, devfn);
69 asm volatile("ldrb %0, [%1, %2]"
70 : "=r" (v) : "r" (addr), "r" (where) : "cc");
73 asm volatile("ldrh %0, [%1, %2]"
74 : "=r" (v) : "r" (addr), "r" (where) : "cc");
77 asm volatile("ldr %0, [%1, %2]"
78 : "=r" (v) : "r" (addr), "r" (where) : "cc");
85 if (v & PCICMD_ABORT) {
86 *CSR_PCICMD = v & (0xffff|PCICMD_ABORT);
90 return PCIBIOS_SUCCESSFUL;
94 dc21285_write_config(struct pci_bus *bus, unsigned int devfn, int where,
97 unsigned long addr = dc21285_base_address(bus, devfn);
103 asm volatile("strb %0, [%1, %2]"
104 : : "r" (value), "r" (addr), "r" (where)
108 asm volatile("strh %0, [%1, %2]"
109 : : "r" (value), "r" (addr), "r" (where)
113 asm volatile("str %0, [%1, %2]"
114 : : "r" (value), "r" (addr), "r" (where)
120 if (v & PCICMD_ABORT) {
121 *CSR_PCICMD = v & (0xffff|PCICMD_ABORT);
125 return PCIBIOS_SUCCESSFUL;
128 struct pci_ops dc21285_ops = {
129 .read = dc21285_read_config,
130 .write = dc21285_write_config,
133 static struct timer_list serr_timer;
134 static struct timer_list perr_timer;
136 static void dc21285_enable_error(struct timer_list *timer)
140 if (timer == &serr_timer)
141 enable_irq(IRQ_PCI_SERR);
142 else if (timer == &perr_timer)
143 enable_irq(IRQ_PCI_PERR);
147 * Warn on PCI errors.
149 static irqreturn_t dc21285_abort_irq(int irq, void *dev_id)
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;
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);
171 cmd |= PCI_STATUS_REC_TARGET_ABORT << 16;
179 static irqreturn_t dc21285_serr_irq(int irq, void *dev_id)
181 struct timer_list *timer = dev_id;
184 printk(KERN_DEBUG "PCI: system error received: ");
185 pcibios_report_status(PCI_STATUS_SIG_SYSTEM_ERROR, 1);
188 cntl = *CSR_SA110_CNTL & 0xffffdf07;
189 *CSR_SA110_CNTL = cntl | SA110_CNTL_RXSERR;
192 * back off this interrupt
195 timer->expires = jiffies + HZ;
201 static irqreturn_t dc21285_discard_irq(int irq, void *dev_id)
203 printk(KERN_DEBUG "PCI: discard timer expired\n");
204 *CSR_SA110_CNTL &= 0xffffde07;
209 static irqreturn_t dc21285_dparity_irq(int irq, void *dev_id)
213 printk(KERN_DEBUG "PCI: data parity error detected: ");
214 pcibios_report_status(PCI_STATUS_PARITY | PCI_STATUS_DETECTED_PARITY, 1);
217 cmd = *CSR_PCICMD & 0xffff;
218 *CSR_PCICMD = cmd | 1 << 24;
223 static irqreturn_t dc21285_parity_irq(int irq, void *dev_id)
225 struct timer_list *timer = dev_id;
228 printk(KERN_DEBUG "PCI: parity error detected: ");
229 pcibios_report_status(PCI_STATUS_PARITY | PCI_STATUS_DETECTED_PARITY, 1);
232 cmd = *CSR_PCICMD & 0xffff;
233 *CSR_PCICMD = cmd | 1 << 31;
236 * back off this interrupt
239 timer->expires = jiffies + HZ;
245 int __init dc21285_setup(int nr, struct pci_sys_data *sys)
247 struct resource *res;
249 if (nr || !footbridge_cfn_mode())
252 res = kcalloc(2, sizeof(struct resource), GFP_KERNEL);
254 printk("out of memory for root bus resources");
258 res[0].flags = IORESOURCE_MEM;
259 res[0].name = "Footbridge non-prefetch";
260 res[1].flags = IORESOURCE_MEM | IORESOURCE_PREFETCH;
261 res[1].name = "Footbridge prefetch";
263 allocate_resource(&iomem_resource, &res[1], 0x20000000,
264 0xa0000000, 0xffffffff, 0x20000000, NULL, NULL);
265 allocate_resource(&iomem_resource, &res[0], 0x40000000,
266 0x80000000, 0xffffffff, 0x40000000, NULL, NULL);
268 sys->mem_offset = DC21285_PCI_MEM;
270 pci_add_resource_offset(&sys->resources, &res[0], sys->mem_offset);
271 pci_add_resource_offset(&sys->resources, &res[1], sys->mem_offset);
276 #define dc21285_request_irq(_a, _b, _c, _d, _e) \
277 WARN_ON(request_irq(_a, _b, _c, _d, _e) < 0)
279 void __init dc21285_preinit(void)
281 unsigned int mem_size, mem_mask;
284 pcibios_min_mem = 0x81000000;
286 mem_size = (unsigned int)high_memory - PAGE_OFFSET;
287 for (mem_mask = 0x00100000; mem_mask < 0x10000000; mem_mask <<= 1)
288 if (mem_mask >= mem_size)
292 * These registers need to be set up whether we're the
293 * central function or not.
295 *CSR_SDRAMBASEMASK = (mem_mask - 1) & 0x0ffc0000;
296 *CSR_SDRAMBASEOFFSET = 0;
297 *CSR_ROMBASEMASK = 0x80000000;
298 *CSR_CSRBASEMASK = 0;
299 *CSR_CSRBASEOFFSET = 0;
300 *CSR_PCIADDR_EXTN = 0;
302 cfn_mode = __footbridge_cfn_mode();
304 printk(KERN_INFO "PCI: DC21285 footbridge, revision %02lX, in "
305 "%s mode\n", *CSR_CLASSREV & 0xff, cfn_mode ?
306 "central function" : "addin");
308 if (footbridge_cfn_mode()) {
310 * Clear any existing errors - we aren't
311 * interested in historical data...
313 *CSR_SA110_CNTL = (*CSR_SA110_CNTL & 0xffffde07) |
315 *CSR_PCICMD = (*CSR_PCICMD & 0xffff) | PCICMD_ERROR_BITS;
318 timer_setup(&serr_timer, dc21285_enable_error, 0);
319 timer_setup(&perr_timer, dc21285_enable_error, 0);
322 * We don't care if these fail.
324 dc21285_request_irq(IRQ_PCI_SERR, dc21285_serr_irq, 0,
325 "PCI system error", &serr_timer);
326 dc21285_request_irq(IRQ_PCI_PERR, dc21285_parity_irq, 0,
327 "PCI parity error", &perr_timer);
328 dc21285_request_irq(IRQ_PCI_ABORT, dc21285_abort_irq, 0,
330 dc21285_request_irq(IRQ_DISCARD_TIMER, dc21285_discard_irq, 0,
331 "Discard timer", NULL);
332 dc21285_request_irq(IRQ_PCI_DPERR, dc21285_dparity_irq, 0,
333 "PCI data parity", NULL);
337 * Map our SDRAM at a known address in PCI space, just in case
338 * the firmware had other ideas. Using a nonzero base is
339 * necessary, since some VGA cards forcefully use PCI addresses
340 * in the range 0x000a0000 to 0x000c0000. (eg, S3 cards).
342 *CSR_PCICSRBASE = 0xf4000000;
343 *CSR_PCICSRIOBASE = 0;
344 *CSR_PCISDRAMBASE = __virt_to_bus(PAGE_OFFSET);
346 *CSR_PCICMD = PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER |
347 PCI_COMMAND_INVALIDATE | PCICMD_ERROR_BITS;
348 } else if (footbridge_cfn_mode() != 0) {
350 * If we are not compiled to accept "add-in" mode, then
351 * we are using a constant virt_to_bus translation which
352 * can not hope to cater for the way the host BIOS has
353 * set up the machine.
355 panic("PCI: this kernel is compiled for central "
356 "function mode only");
360 void __init dc21285_postinit(void)
362 register_isa_ports(DC21285_PCI_MEM, DC21285_PCI_IO, 0);