1 // SPDX-License-Identifier: GPL-2.0
3 * linux/arch/arm/kernel/bios32.c
5 * PCI bios-type initialisation for PCI machines
7 * Bits taken from various places.
9 #include <linux/export.h>
10 #include <linux/kernel.h>
11 #include <linux/pci.h>
12 #include <linux/slab.h>
13 #include <linux/init.h>
16 #include <asm/mach-types.h>
17 #include <asm/mach/map.h>
18 #include <asm/mach/pci.h>
23 * We can't use pci_get_device() here since we are
24 * called from interrupt context.
26 static void pcibios_bus_report_status(struct pci_bus
*bus
, u_int status_mask
, int warn
)
30 list_for_each_entry(dev
, &bus
->devices
, bus_list
) {
34 * ignore host bridge - we handle
37 if (dev
->bus
->number
== 0 && dev
->devfn
== 0)
40 pci_read_config_word(dev
, PCI_STATUS
, &status
);
44 if ((status
& status_mask
) == 0)
47 /* clear the status errors */
48 pci_write_config_word(dev
, PCI_STATUS
, status
& status_mask
);
51 printk("(%s: %04X) ", pci_name(dev
), status
);
54 list_for_each_entry(dev
, &bus
->devices
, bus_list
)
56 pcibios_bus_report_status(dev
->subordinate
, status_mask
, warn
);
59 void pcibios_report_status(u_int status_mask
, int warn
)
63 list_for_each_entry(bus
, &pci_root_buses
, node
)
64 pcibios_bus_report_status(bus
, status_mask
, warn
);
68 * We don't use this to fix the device, but initialisation of it.
69 * It's not the correct use for this, but it works.
70 * Note that the arbiter/ISA bridge appears to be buggy, specifically in
73 * 2. ISA bridge ping-pong
74 * 3. ISA bridge master handling of target RETRY
76 * Bug 3 is responsible for the sound DMA grinding to a halt. We now
79 static void pci_fixup_83c553(struct pci_dev
*dev
)
82 * Set memory region to start at address 0, and enable IO
84 pci_write_config_dword(dev
, PCI_BASE_ADDRESS_0
, PCI_BASE_ADDRESS_SPACE_MEMORY
);
85 pci_write_config_word(dev
, PCI_COMMAND
, PCI_COMMAND_IO
);
87 dev
->resource
[0].end
-= dev
->resource
[0].start
;
88 dev
->resource
[0].start
= 0;
91 * All memory requests from ISA to be channelled to PCI
93 pci_write_config_byte(dev
, 0x48, 0xff);
96 * Enable ping-pong on bus master to ISA bridge transactions.
97 * This improves the sound DMA substantially. The fixed
98 * priority arbiter also helps (see below).
100 pci_write_config_byte(dev
, 0x42, 0x01);
105 pci_write_config_byte(dev
, 0x40, 0x22);
108 * We used to set the arbiter to "park on last master" (bit
109 * 1 set), but unfortunately the CyberPro does not park the
110 * bus. We must therefore park on CPU. Unfortunately, this
111 * may trigger yet another bug in the 553.
113 pci_write_config_byte(dev
, 0x83, 0x02);
116 * Make the ISA DMA request lowest priority, and disable
117 * rotating priorities completely.
119 pci_write_config_byte(dev
, 0x80, 0x11);
120 pci_write_config_byte(dev
, 0x81, 0x00);
123 * Route INTA input to IRQ 11, and set IRQ11 to be level
126 pci_write_config_word(dev
, 0x44, 0xb000);
129 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_WINBOND
, PCI_DEVICE_ID_WINBOND_83C553
, pci_fixup_83c553
);
131 static void pci_fixup_unassign(struct pci_dev
*dev
)
133 dev
->resource
[0].end
-= dev
->resource
[0].start
;
134 dev
->resource
[0].start
= 0;
136 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_WINBOND2
, PCI_DEVICE_ID_WINBOND2_89C940F
, pci_fixup_unassign
);
139 * Prevent the PCI layer from seeing the resources allocated to this device
140 * if it is the host bridge by marking it as such. These resources are of
141 * no consequence to the PCI layer (they are handled elsewhere).
143 static void pci_fixup_dec21285(struct pci_dev
*dev
)
145 if (dev
->devfn
== 0) {
149 dev
->class |= PCI_CLASS_BRIDGE_HOST
<< 8;
150 pci_dev_for_each_resource(dev
, r
) {
157 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_DEC
, PCI_DEVICE_ID_DEC_21285
, pci_fixup_dec21285
);
160 * PCI IDE controllers use non-standard I/O port decoding, respect it.
162 static void pci_fixup_ide_bases(struct pci_dev
*dev
)
166 if ((dev
->class >> 8) != PCI_CLASS_STORAGE_IDE
)
169 pci_dev_for_each_resource(dev
, r
) {
170 if ((r
->start
& ~0x80) == 0x374) {
176 DECLARE_PCI_FIXUP_HEADER(PCI_ANY_ID
, PCI_ANY_ID
, pci_fixup_ide_bases
);
179 * Put the DEC21142 to sleep
181 static void pci_fixup_dec21142(struct pci_dev
*dev
)
183 pci_write_config_dword(dev
, 0x40, 0x80000000);
185 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_DEC
, PCI_DEVICE_ID_DEC_21142
, pci_fixup_dec21142
);
188 * The CY82C693 needs some rather major fixups to ensure that it does
189 * the right thing. Idea from the Alpha people, with a few additions.
191 * We ensure that the IDE base registers are set to 1f0/3f4 for the
192 * primary bus, and 170/374 for the secondary bus. Also, hide them
193 * from the PCI subsystem view as well so we won't try to perform
194 * our own auto-configuration on them.
196 * In addition, we ensure that the PCI IDE interrupts are routed to
197 * IRQ 14 and IRQ 15 respectively.
199 * The above gets us to a point where the IDE on this device is
200 * functional. However, The CY82C693U _does not work_ in bus
201 * master mode without locking the PCI bus solid.
203 static void pci_fixup_cy82c693(struct pci_dev
*dev
)
205 if ((dev
->class >> 8) == PCI_CLASS_STORAGE_IDE
) {
208 if (dev
->class & 0x80) { /* primary */
211 } else { /* secondary */
216 pci_write_config_dword(dev
, PCI_BASE_ADDRESS_0
,
217 base0
| PCI_BASE_ADDRESS_SPACE_IO
);
218 pci_write_config_dword(dev
, PCI_BASE_ADDRESS_1
,
219 base1
| PCI_BASE_ADDRESS_SPACE_IO
);
221 dev
->resource
[0].start
= 0;
222 dev
->resource
[0].end
= 0;
223 dev
->resource
[0].flags
= 0;
225 dev
->resource
[1].start
= 0;
226 dev
->resource
[1].end
= 0;
227 dev
->resource
[1].flags
= 0;
228 } else if (PCI_FUNC(dev
->devfn
) == 0) {
230 * Setup IDE IRQ routing.
232 pci_write_config_byte(dev
, 0x4b, 14);
233 pci_write_config_byte(dev
, 0x4c, 15);
236 * Disable FREQACK handshake, enable USB.
238 pci_write_config_byte(dev
, 0x4d, 0x41);
241 * Enable PCI retry, and PCI post-write buffer.
243 pci_write_config_byte(dev
, 0x44, 0x17);
246 * Enable ISA master and DMA post write buffering.
248 pci_write_config_byte(dev
, 0x45, 0x03);
251 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_CONTAQ
, PCI_DEVICE_ID_CONTAQ_82C693
, pci_fixup_cy82c693
);
254 * If the bus contains any of these devices, then we must not turn on
255 * parity checking of any kind. Currently this is CyberPro 20x0 only.
257 static inline int pdev_bad_for_parity(struct pci_dev
*dev
)
259 return ((dev
->vendor
== PCI_VENDOR_ID_INTERG
&&
260 (dev
->device
== PCI_DEVICE_ID_INTERG_2000
||
261 dev
->device
== PCI_DEVICE_ID_INTERG_2010
)) ||
262 (dev
->vendor
== PCI_VENDOR_ID_ITE
&&
263 dev
->device
== PCI_DEVICE_ID_ITE_8152
));
268 * pcibios_fixup_bus - Called after each bus is probed,
269 * but before its children are examined.
271 void pcibios_fixup_bus(struct pci_bus
*bus
)
274 u16 features
= PCI_COMMAND_SERR
| PCI_COMMAND_PARITY
| PCI_COMMAND_FAST_BACK
;
277 * Walk the devices on this bus, working out what we can
280 list_for_each_entry(dev
, &bus
->devices
, bus_list
) {
283 pci_read_config_word(dev
, PCI_STATUS
, &status
);
286 * If any device on this bus does not support fast back
287 * to back transfers, then the bus as a whole is not able
288 * to support them. Having fast back to back transfers
289 * on saves us one PCI cycle per transaction.
291 if (!(status
& PCI_STATUS_FAST_BACK
))
292 features
&= ~PCI_COMMAND_FAST_BACK
;
294 if (pdev_bad_for_parity(dev
))
295 features
&= ~(PCI_COMMAND_SERR
| PCI_COMMAND_PARITY
);
297 switch (dev
->class >> 8) {
298 case PCI_CLASS_BRIDGE_PCI
:
299 pci_read_config_word(dev
, PCI_BRIDGE_CONTROL
, &status
);
300 status
|= PCI_BRIDGE_CTL_PARITY
|PCI_BRIDGE_CTL_MASTER_ABORT
;
301 status
&= ~(PCI_BRIDGE_CTL_BUS_RESET
|PCI_BRIDGE_CTL_FAST_BACK
);
302 pci_write_config_word(dev
, PCI_BRIDGE_CONTROL
, status
);
305 case PCI_CLASS_BRIDGE_CARDBUS
:
306 pci_read_config_word(dev
, PCI_CB_BRIDGE_CONTROL
, &status
);
307 status
|= PCI_CB_BRIDGE_CTL_PARITY
|PCI_CB_BRIDGE_CTL_MASTER_ABORT
;
308 pci_write_config_word(dev
, PCI_CB_BRIDGE_CONTROL
, status
);
314 * Now walk the devices again, this time setting them up.
316 list_for_each_entry(dev
, &bus
->devices
, bus_list
) {
319 pci_read_config_word(dev
, PCI_COMMAND
, &cmd
);
321 pci_write_config_word(dev
, PCI_COMMAND
, cmd
);
323 pci_write_config_byte(dev
, PCI_CACHE_LINE_SIZE
,
324 L1_CACHE_BYTES
>> 2);
328 * Propagate the flags to the PCI bridge.
330 if (bus
->self
&& bus
->self
->hdr_type
== PCI_HEADER_TYPE_BRIDGE
) {
331 if (features
& PCI_COMMAND_FAST_BACK
)
332 bus
->bridge_ctl
|= PCI_BRIDGE_CTL_FAST_BACK
;
333 if (features
& PCI_COMMAND_PARITY
)
334 bus
->bridge_ctl
|= PCI_BRIDGE_CTL_PARITY
;
338 * Report what we did for this bus
340 pr_info("PCI: bus%d: Fast back to back transfers %sabled\n",
341 bus
->number
, (features
& PCI_COMMAND_FAST_BACK
) ? "en" : "dis");
343 EXPORT_SYMBOL(pcibios_fixup_bus
);
346 * Swizzle the device pin each time we cross a bridge. If a platform does
347 * not provide a swizzle function, we perform the standard PCI swizzling.
349 * The default swizzling walks up the bus tree one level at a time, applying
350 * the standard swizzle function at each step, stopping when it finds the PCI
351 * root bus. This will return the slot number of the bridge device on the
352 * root bus and the interrupt pin on that device which should correspond
353 * with the downstream device interrupt.
355 * Platforms may override this, in which case the slot and pin returned
356 * depend entirely on the platform code. However, please note that the
357 * PCI standard swizzle is implemented on plug-in cards and Cardbus based
358 * PCI extenders, so it can not be ignored.
360 static u8
pcibios_swizzle(struct pci_dev
*dev
, u8
*pin
)
362 struct pci_sys_data
*sys
= dev
->sysdata
;
363 int slot
, oldpin
= *pin
;
366 slot
= sys
->swizzle(dev
, pin
);
368 slot
= pci_common_swizzle(dev
, pin
);
371 printk("PCI: %s swizzling pin %d => pin %d slot %d\n",
372 pci_name(dev
), oldpin
, *pin
, slot
);
378 * Map a slot/pin to an IRQ.
380 static int pcibios_map_irq(const struct pci_dev
*dev
, u8 slot
, u8 pin
)
382 struct pci_sys_data
*sys
= dev
->sysdata
;
386 irq
= sys
->map_irq(dev
, slot
, pin
);
389 printk("PCI: %s mapping slot %d pin %d => irq %d\n",
390 pci_name(dev
), slot
, pin
, irq
);
395 static int pcibios_init_resource(int busnr
, struct pci_sys_data
*sys
)
398 struct resource_entry
*window
;
400 if (list_empty(&sys
->resources
)) {
401 pci_add_resource_offset(&sys
->resources
,
402 &iomem_resource
, sys
->mem_offset
);
405 resource_list_for_each_entry(window
, &sys
->resources
)
406 if (resource_type(window
->res
) == IORESOURCE_IO
)
409 sys
->io_res
.start
= (busnr
* SZ_64K
) ? : pcibios_min_io
;
410 sys
->io_res
.end
= (busnr
+ 1) * SZ_64K
- 1;
411 sys
->io_res
.flags
= IORESOURCE_IO
;
412 sys
->io_res
.name
= sys
->io_res_name
;
413 sprintf(sys
->io_res_name
, "PCI%d I/O", busnr
);
415 ret
= request_resource(&ioport_resource
, &sys
->io_res
);
417 pr_err("PCI: unable to allocate I/O port region (%d)\n", ret
);
420 pci_add_resource_offset(&sys
->resources
, &sys
->io_res
,
426 static void pcibios_init_hw(struct device
*parent
, struct hw_pci
*hw
,
427 struct list_head
*head
)
429 struct pci_sys_data
*sys
= NULL
;
433 for (nr
= busnr
= 0; nr
< hw
->nr_controllers
; nr
++) {
434 struct pci_host_bridge
*bridge
;
436 bridge
= pci_alloc_host_bridge(sizeof(struct pci_sys_data
));
437 if (WARN(!bridge
, "PCI: unable to allocate bridge!"))
440 sys
= pci_host_bridge_priv(bridge
);
443 sys
->swizzle
= hw
->swizzle
;
444 sys
->map_irq
= hw
->map_irq
;
445 INIT_LIST_HEAD(&sys
->resources
);
447 if (hw
->private_data
)
448 sys
->private_data
= hw
->private_data
[nr
];
450 ret
= hw
->setup(nr
, sys
);
454 ret
= pcibios_init_resource(nr
, sys
);
456 pci_free_host_bridge(bridge
);
460 bridge
->map_irq
= pcibios_map_irq
;
461 bridge
->swizzle_irq
= pcibios_swizzle
;
464 ret
= hw
->scan(nr
, bridge
);
466 list_splice_init(&sys
->resources
,
468 bridge
->dev
.parent
= parent
;
469 bridge
->sysdata
= sys
;
470 bridge
->busnr
= sys
->busnr
;
471 bridge
->ops
= hw
->ops
;
473 ret
= pci_scan_root_bus_bridge(bridge
);
476 if (WARN(ret
< 0, "PCI: unable to scan bus!")) {
477 pci_free_host_bridge(bridge
);
481 sys
->bus
= bridge
->bus
;
483 busnr
= sys
->bus
->busn_res
.end
+ 1;
485 list_add(&sys
->node
, head
);
487 pci_free_host_bridge(bridge
);
494 void pci_common_init_dev(struct device
*parent
, struct hw_pci
*hw
)
496 struct pci_sys_data
*sys
;
499 pci_add_flags(PCI_REASSIGN_ALL_BUS
);
502 pcibios_init_hw(parent
, hw
, &head
);
506 list_for_each_entry(sys
, &head
, node
) {
507 struct pci_bus
*bus
= sys
->bus
;
510 * We insert PCI resources into the iomem_resource and
511 * ioport_resource trees in either pci_bus_claim_resources()
512 * or pci_bus_assign_resources().
514 if (pci_has_flag(PCI_PROBE_ONLY
)) {
515 pci_bus_claim_resources(bus
);
517 struct pci_bus
*child
;
519 pci_bus_size_bridges(bus
);
520 pci_bus_assign_resources(bus
);
522 list_for_each_entry(child
, &bus
->children
, node
)
523 pcie_bus_configure_settings(child
);
526 pci_bus_add_devices(bus
);
530 #ifndef CONFIG_PCI_HOST_ITE8152
531 void pcibios_set_master(struct pci_dev
*dev
)
533 /* No special bus mastering setup handling */
537 char * __init
pcibios_setup(char *str
)
539 if (!strcmp(str
, "debug")) {
547 * From arch/i386/kernel/pci-i386.c:
549 * We need to avoid collisions with `mirrored' VGA ports
550 * and other strange ISA hardware, so we always want the
551 * addresses to be allocated in the 0x000-0x0ff region
554 * Why? Because some silly external IO cards only decode
555 * the low 10 bits of the IO address. The 0x00-0xff region
556 * is reserved for motherboard devices that decode all 16
557 * bits, so it's ok to allocate at, say, 0x2800-0x28ff,
558 * but we want to try to avoid allocating at 0x2900-0x2bff
559 * which might be mirrored at 0x0100-0x03ff..
561 resource_size_t
pcibios_align_resource(void *data
, const struct resource
*res
,
562 resource_size_t size
, resource_size_t align
)
564 struct pci_dev
*dev
= data
;
565 resource_size_t start
= res
->start
;
566 struct pci_host_bridge
*host_bridge
;
568 if (res
->flags
& IORESOURCE_IO
&& start
& 0x300)
569 start
= (start
+ 0x3ff) & ~0x3ff;
571 start
= (start
+ align
- 1) & ~(align
- 1);
573 host_bridge
= pci_find_host_bridge(dev
->bus
);
575 if (host_bridge
->align_resource
)
576 return host_bridge
->align_resource(dev
, res
,
582 void __init
pci_map_io_early(unsigned long pfn
)
584 struct map_desc pci_io_desc
= {
585 .virtual = PCI_IO_VIRT_BASE
,
590 pci_io_desc
.pfn
= pfn
;
591 iotable_init(&pci_io_desc
, 1);