2 * arch/v850/kernel/mb_a_pci.c -- PCI support for Midas lab RTE-MOTHER-A board
4 * Copyright (C) 2001,02,03 NEC Electronics Corporation
5 * Copyright (C) 2001,02,03 Miles Bader <miles@gnu.org>
7 * This file is subject to the terms and conditions of the GNU General
8 * Public License. See the file COPYING in the main directory of this
9 * archive for more details.
11 * Written by Miles Bader <miles@gnu.org>
14 #include <linux/config.h>
15 #include <linux/kernel.h>
16 #include <linux/module.h>
17 #include <linux/init.h>
18 #include <linux/slab.h>
19 #include <linux/spinlock.h>
20 #include <linux/pci.h>
22 #include <asm/machdep.h>
24 /* __nomods_init is like __devinit, but is a no-op when modules are enabled.
25 This is used by some routines that can be called either during boot
28 #define __nomods_init /*nothing*/
30 #define __nomods_init __devinit
33 /* PCI devices on the Mother-A board can only do DMA to/from the MB SRAM
34 (the RTE-V850E/MA1-CB cpu board doesn't support PCI access to
35 CPU-board memory), and since linux DMA buffers are allocated in
36 normal kernel memory, we basically have to copy DMA blocks around
37 (this is like a `bounce buffer'). When a DMA block is `mapped', we
38 allocate an identically sized block in MB SRAM, and if we're doing
39 output to the device, copy the CPU-memory block to the MB-SRAM block.
40 When an active block is `unmapped', we will copy the block back to
41 CPU memory if necessary, and then deallocate the MB SRAM block.
44 /* Where the motherboard SRAM is in the PCI-bus address space (the
45 first 512K of it is also mapped at PCI address 0). */
46 #define PCI_MB_SRAM_ADDR 0x800000
48 /* Convert CPU-view MB SRAM address to/from PCI-view addresses of the
50 #define MB_SRAM_TO_PCI(mb_sram_addr) \
51 ((dma_addr_t)mb_sram_addr - MB_A_SRAM_ADDR + PCI_MB_SRAM_ADDR)
52 #define PCI_TO_MB_SRAM(pci_addr) \
53 (void *)(pci_addr - PCI_MB_SRAM_ADDR + MB_A_SRAM_ADDR)
55 static void pcibios_assign_resources (void);
57 struct mb_pci_dev_irq {
58 unsigned dev; /* PCI device number */
59 unsigned irq_base; /* First IRQ */
60 unsigned query_pin; /* True if we should read the device's
61 Interrupt Pin info, and allocate
62 interrupt IRQ_BASE + PIN. */
65 /* PCI interrupts are mapped statically to GBUS interrupts. */
66 static struct mb_pci_dev_irq mb_pci_dev_irqs[] = {
67 /* Motherboard SB82558 ethernet controller */
68 { 10, IRQ_MB_A_LAN, 0 },
70 { 8, IRQ_MB_A_PCI1(0), 1 },
72 { 9, IRQ_MB_A_PCI2(0), 1 }
74 #define NUM_MB_PCI_DEV_IRQS \
75 (sizeof mb_pci_dev_irqs / sizeof mb_pci_dev_irqs[0])
78 /* PCI configuration primitives. */
80 #define CONFIG_DMCFGA(bus, devfn, offs) \
84 | ((bus)->number << 16))
87 mb_pci_read (struct pci_bus *bus, unsigned devfn, int offs, int size, u32 *rval)
92 local_irq_save (flags);
95 MB_A_PCI_DMCFGA = CONFIG_DMCFGA (bus, devfn, offs);
97 addr = MB_A_PCI_IO_ADDR + (offs & 0x3);
100 case 1: *rval = *(volatile u8 *)addr; break;
101 case 2: *rval = *(volatile u16 *)addr; break;
102 case 4: *rval = *(volatile u32 *)addr; break;
105 if (MB_A_PCI_PCISR & 0x2000) {
106 MB_A_PCI_PCISR = 0x2000;
112 local_irq_restore (flags);
114 return PCIBIOS_SUCCESSFUL;
118 mb_pci_write (struct pci_bus *bus, unsigned devfn, int offs, int size, u32 val)
123 local_irq_save (flags);
125 MB_A_PCI_PCICR = 0x7;
126 MB_A_PCI_DMCFGA = CONFIG_DMCFGA (bus, devfn, offs);
128 addr = MB_A_PCI_IO_ADDR + (offs & 0x3);
131 case 1: *(volatile u8 *)addr = val; break;
132 case 2: *(volatile u16 *)addr = val; break;
133 case 4: *(volatile u32 *)addr = val; break;
136 if (MB_A_PCI_PCISR & 0x2000)
137 MB_A_PCI_PCISR = 0x2000;
141 local_irq_restore (flags);
143 return PCIBIOS_SUCCESSFUL;
146 static struct pci_ops mb_pci_config_ops = {
148 .write = mb_pci_write,
152 /* PCI Initialization. */
154 static struct pci_bus *mb_pci_bus = 0;
156 /* Do initial PCI setup. */
157 static int __devinit pcibios_init (void)
159 u32 id = MB_A_PCI_PCIHIDR;
160 u16 vendor = id & 0xFFFF;
161 u16 device = (id >> 16) & 0xFFFF;
163 if (vendor == PCI_VENDOR_ID_PLX && device == PCI_DEVICE_ID_PLX_9080) {
165 "PCI: PLX Technology PCI9080 HOST/PCI bridge\n");
167 MB_A_PCI_PCICR = 0x147;
169 MB_A_PCI_PCIBAR0 = 0x007FFF00;
170 MB_A_PCI_PCIBAR1 = 0x0000FF00;
171 MB_A_PCI_PCIBAR2 = 0x00800000;
173 MB_A_PCI_PCILTR = 0x20;
175 MB_A_PCI_PCIPBAM |= 0x3;
177 MB_A_PCI_PCISR = ~0; /* Clear errors. */
179 /* Reprogram the motherboard's IO/config address space,
180 as we don't support the GCS7 address space that the
183 /* Significant address bits used for decoding PCI GCS5 space
185 MB_A_PCI_DMRR = ~(MB_A_PCI_MEM_SIZE - 1);
187 /* I don't understand this, but the SolutionGear example code
188 uses such an offset, and it doesn't work without it. XXX */
189 #if GCS5_SIZE == 0x00800000
190 #define GCS5_CFG_OFFS 0x00800000
192 #define GCS5_CFG_OFFS 0
195 /* Address bit values for matching. Note that we have to give
196 the address from the motherboard's point of view, which is
197 different than the CPU's. */
198 /* PCI memory space. */
199 MB_A_PCI_DMLBAM = GCS5_CFG_OFFS + 0x0;
202 GCS5_CFG_OFFS + (MB_A_PCI_IO_ADDR - GCS5_ADDR);
204 mb_pci_bus = pci_scan_bus (0, &mb_pci_config_ops, 0);
206 pcibios_assign_resources ();
208 printk (KERN_ERR "PCI: HOST/PCI bridge not found\n");
213 subsys_initcall (pcibios_init);
215 char __devinit *pcibios_setup (char *option)
217 /* Don't handle any options. */
222 int __nomods_init pcibios_enable_device (struct pci_dev *dev, int mask)
228 pci_read_config_word(dev, PCI_COMMAND, &cmd);
230 for (idx = 0; idx < 6; idx++) {
231 r = &dev->resource[idx];
232 if (!r->start && r->end) {
233 printk(KERN_ERR "PCI: Device %s not available because "
234 "of resource collisions\n", pci_name(dev));
237 if (r->flags & IORESOURCE_IO)
238 cmd |= PCI_COMMAND_IO;
239 if (r->flags & IORESOURCE_MEM)
240 cmd |= PCI_COMMAND_MEMORY;
242 if (cmd != old_cmd) {
243 printk("PCI: Enabling device %s (%04x -> %04x)\n",
244 pci_name(dev), old_cmd, cmd);
245 pci_write_config_word(dev, PCI_COMMAND, cmd);
251 /* Resource allocation. */
252 static void __devinit pcibios_assign_resources (void)
254 struct pci_dev *dev = NULL;
257 while ((dev = pci_find_device(PCI_ANY_ID, PCI_ANY_ID, dev)) != NULL) {
259 unsigned class = dev->class >> 8;
261 if (class && class != PCI_CLASS_BRIDGE_HOST) {
263 for(r_num = 0; r_num < 6; r_num++) {
264 r = &dev->resource[r_num];
265 if (!r->start && r->end)
266 pci_assign_resource (dev, r_num);
270 /* Assign interrupts. */
271 for (di_num = 0; di_num < NUM_MB_PCI_DEV_IRQS; di_num++) {
272 struct mb_pci_dev_irq *di = &mb_pci_dev_irqs[di_num];
274 if (di->dev == PCI_SLOT (dev->devfn)) {
275 unsigned irq = di->irq_base;
278 /* Find out which interrupt pin
279 this device uses (each PCI
283 pci_read_config_byte (dev,
288 /* Doesn't use interrupts. */
294 pcibios_update_irq (dev, irq);
300 void __devinit pcibios_update_irq (struct pci_dev *dev, int irq)
303 pci_write_config_byte (dev, PCI_INTERRUPT_LINE, irq);
307 pcibios_resource_to_bus(struct pci_dev *dev, struct pci_bus_region *region,
308 struct resource *res)
310 unsigned long offset = 0;
312 if (res->flags & IORESOURCE_IO) {
313 offset = MB_A_PCI_IO_ADDR;
314 } else if (res->flags & IORESOURCE_MEM) {
315 offset = MB_A_PCI_MEM_ADDR;
318 region->start = res->start - offset;
319 region->end = res->end - offset;
323 /* Stubs for things we don't use. */
325 struct pci_fixup pcibios_fixups[] = { { 0 } };
327 /* Called after each bus is probed, but before its children are examined. */
328 void pcibios_fixup_bus(struct pci_bus *b)
333 pcibios_align_resource (void *data, struct resource *res,
334 unsigned long size, unsigned long align)
338 void pcibios_set_master (struct pci_dev *dev)
343 /* Mother-A SRAM memory allocation. This is a simple first-fit allocator. */
345 /* A memory free-list node. */
346 struct mb_sram_free_area {
349 struct mb_sram_free_area *next;
352 /* The tail of the free-list, which starts out containing all the SRAM. */
353 static struct mb_sram_free_area mb_sram_free_tail = {
354 (void *)MB_A_SRAM_ADDR, MB_A_SRAM_SIZE, 0
358 static struct mb_sram_free_area *mb_sram_free_areas = &mb_sram_free_tail;
360 /* The free-list of free free-list nodes. (:-) */
361 static struct mb_sram_free_area *mb_sram_free_free_areas = 0;
363 /* Spinlock protecting the above globals. */
364 static spinlock_t mb_sram_lock = SPIN_LOCK_UNLOCKED;
366 /* Allocate a memory block at least SIZE bytes long in the Mother-A SRAM
368 static void *alloc_mb_sram (size_t size)
370 struct mb_sram_free_area *prev, *fa;
374 spin_lock_irqsave (mb_sram_lock, flags);
376 /* Look for a free area that can contain SIZE bytes. */
377 for (prev = 0, fa = mb_sram_free_areas; fa; prev = fa, fa = fa->next)
378 if (fa->size >= size) {
382 if (fa->size == size) {
383 /* In fact, it fits exactly, so remove
384 this node from the free-list. */
386 prev->next = fa->next;
388 mb_sram_free_areas = fa->next;
389 /* Put it on the free-list-entry-free-list. */
390 fa->next = mb_sram_free_free_areas;
391 mb_sram_free_free_areas = fa;
393 /* FA is bigger than SIZE, so just
394 reduce its size to account for this
403 spin_unlock_irqrestore (mb_sram_lock, flags);
408 /* Return the memory area MEM of size SIZE to the MB SRAM free pool. */
409 static void free_mb_sram (void *mem, size_t size)
411 struct mb_sram_free_area *prev, *fa, *new_fa;
413 void *end = mem + size;
415 spin_lock_irqsave (mb_sram_lock, flags);
418 /* Find an adjacent free-list entry. */
419 for (prev = 0, fa = mb_sram_free_areas; fa; prev = fa, fa = fa->next)
420 if (fa->mem == end) {
421 /* FA is just after MEM, grow down to encompass it. */
425 } else if (fa->mem + fa->size == mem) {
426 struct mb_sram_free_area *next_fa = fa->next;
428 /* FA is just before MEM, expand to encompass it. */
431 /* See if FA can now be merged with its successor. */
432 if (next_fa && fa->mem + fa->size == next_fa->mem) {
433 /* Yup; merge NEXT_FA's info into FA. */
434 fa->size += next_fa->size;
435 fa->next = next_fa->next;
437 next_fa->next = mb_sram_free_free_areas;
438 mb_sram_free_free_areas = next_fa;
441 } else if (fa->mem > mem)
442 /* We've reached the right spot in the free-list
443 without finding an adjacent free-area, so add
444 a new free area to hold mem. */
447 /* Make a new free-list entry. */
449 /* First, get a free-list entry. */
450 if (! mb_sram_free_free_areas) {
451 /* There are none, so make some. */
453 size_t block_size = sizeof (struct mb_sram_free_area) * 8;
455 /* Don't hold the lock while calling kmalloc (I'm not
456 sure whether it would be a problem, since we use
457 GFP_ATOMIC, but it makes me nervous). */
458 spin_unlock_irqrestore (mb_sram_lock, flags);
460 block = kmalloc (block_size, GFP_ATOMIC);
462 panic ("free_mb_sram: can't allocate free-list entry");
464 /* Now get the lock back. */
465 spin_lock_irqsave (mb_sram_lock, flags);
467 /* Add the new free free-list entries. */
468 while (block_size > 0) {
469 struct mb_sram_free_area *nfa = block;
470 nfa->next = mb_sram_free_free_areas;
471 mb_sram_free_free_areas = nfa;
472 block += sizeof *nfa;
473 block_size -= sizeof *nfa;
476 /* Since we dropped the lock to call kmalloc, the
477 free-list could have changed, so retry from the
482 /* Remove NEW_FA from the free-list of free-list entries. */
483 new_fa = mb_sram_free_free_areas;
484 mb_sram_free_free_areas = new_fa->next;
486 /* NEW_FA initially holds only MEM. */
490 /* Insert NEW_FA in the free-list between PREV and FA. */
495 mb_sram_free_areas = new_fa;
498 spin_unlock_irqrestore (mb_sram_lock, flags);
502 /* Maintainence of CPU -> Mother-A DMA mappings. */
508 struct dma_mapping *next;
511 /* A list of mappings from CPU addresses to MB SRAM addresses for active
512 DMA blocks (that have been `granted' to the PCI device). */
513 static struct dma_mapping *active_dma_mappings = 0;
515 /* A list of free mapping objects. */
516 static struct dma_mapping *free_dma_mappings = 0;
518 /* Spinlock protecting the above globals. */
519 static spinlock_t dma_mappings_lock = SPIN_LOCK_UNLOCKED;
521 static struct dma_mapping *new_dma_mapping (size_t size)
524 struct dma_mapping *mapping;
525 void *mb_sram_block = alloc_mb_sram (size);
530 spin_lock_irqsave (dma_mappings_lock, flags);
532 if (! free_dma_mappings) {
533 /* We're out of mapping structures, make more. */
535 size_t mblock_size = sizeof (struct dma_mapping) * 8;
537 /* Don't hold the lock while calling kmalloc (I'm not
538 sure whether it would be a problem, since we use
539 GFP_ATOMIC, but it makes me nervous). */
540 spin_unlock_irqrestore (dma_mappings_lock, flags);
542 mblock = kmalloc (mblock_size, GFP_ATOMIC);
544 free_mb_sram (mb_sram_block, size);
548 /* Get the lock back. */
549 spin_lock_irqsave (dma_mappings_lock, flags);
551 /* Add the new mapping structures to the free-list. */
552 while (mblock_size > 0) {
553 struct dma_mapping *fm = mblock;
554 fm->next = free_dma_mappings;
555 free_dma_mappings = fm;
556 mblock += sizeof *fm;
557 mblock_size -= sizeof *fm;
561 /* Get a mapping struct from the freelist. */
562 mapping = free_dma_mappings;
563 free_dma_mappings = mapping->next;
565 /* Initialize the mapping. Other fields should be filled in by
567 mapping->mb_sram_addr = mb_sram_block;
568 mapping->size = size;
570 /* Add it to the list of active mappings. */
571 mapping->next = active_dma_mappings;
572 active_dma_mappings = mapping;
574 spin_unlock_irqrestore (dma_mappings_lock, flags);
579 static struct dma_mapping *find_dma_mapping (void *mb_sram_addr)
582 struct dma_mapping *mapping;
584 spin_lock_irqsave (dma_mappings_lock, flags);
586 for (mapping = active_dma_mappings; mapping; mapping = mapping->next)
587 if (mapping->mb_sram_addr == mb_sram_addr) {
588 spin_unlock_irqrestore (dma_mappings_lock, flags);
592 panic ("find_dma_mapping: unmapped PCI DMA addr 0x%x",
593 MB_SRAM_TO_PCI (mb_sram_addr));
596 static struct dma_mapping *deactivate_dma_mapping (void *mb_sram_addr)
599 struct dma_mapping *mapping, *prev;
601 spin_lock_irqsave (dma_mappings_lock, flags);
603 for (prev = 0, mapping = active_dma_mappings;
605 prev = mapping, mapping = mapping->next)
607 if (mapping->mb_sram_addr == mb_sram_addr) {
608 /* This is the MAPPING; deactivate it. */
610 prev->next = mapping->next;
612 active_dma_mappings = mapping->next;
614 spin_unlock_irqrestore (dma_mappings_lock, flags);
620 panic ("deactivate_dma_mapping: unmapped PCI DMA addr 0x%x",
621 MB_SRAM_TO_PCI (mb_sram_addr));
624 /* Return MAPPING to the freelist. */
626 free_dma_mapping (struct dma_mapping *mapping)
630 free_mb_sram (mapping->mb_sram_addr, mapping->size);
632 spin_lock_irqsave (dma_mappings_lock, flags);
634 mapping->next = free_dma_mappings;
635 free_dma_mappings = mapping;
637 spin_unlock_irqrestore (dma_mappings_lock, flags);
641 /* Single PCI DMA mappings. */
643 /* `Grant' to PDEV the memory block at CPU_ADDR, for doing DMA. The
644 32-bit PCI bus mastering address to use is returned. the device owns
645 this memory until either pci_unmap_single or pci_dma_sync_single is
648 pci_map_single (struct pci_dev *pdev, void *cpu_addr, size_t size, int dir)
650 struct dma_mapping *mapping = new_dma_mapping (size);
655 mapping->cpu_addr = cpu_addr;
657 if (dir == PCI_DMA_BIDIRECTIONAL || dir == PCI_DMA_TODEVICE)
658 memcpy (mapping->mb_sram_addr, cpu_addr, size);
660 return MB_SRAM_TO_PCI (mapping->mb_sram_addr);
663 /* Return to the CPU the PCI DMA memory block previously `granted' to
664 PDEV, at DMA_ADDR. */
665 void pci_unmap_single (struct pci_dev *pdev, dma_addr_t dma_addr, size_t size,
668 void *mb_sram_addr = PCI_TO_MB_SRAM (dma_addr);
669 struct dma_mapping *mapping = deactivate_dma_mapping (mb_sram_addr);
671 if (size != mapping->size)
672 panic ("pci_unmap_single: size (%d) doesn't match"
673 " size of mapping at PCI DMA addr 0x%x (%d)\n",
674 size, dma_addr, mapping->size);
676 /* Copy back the DMA'd contents if necessary. */
677 if (dir == PCI_DMA_BIDIRECTIONAL || dir == PCI_DMA_FROMDEVICE)
678 memcpy (mapping->cpu_addr, mb_sram_addr, size);
680 /* Return mapping to the freelist. */
681 free_dma_mapping (mapping);
684 /* Make physical memory consistent for a single streaming mode DMA
685 translation after a transfer.
687 If you perform a pci_map_single() but wish to interrogate the
688 buffer using the cpu, yet do not wish to teardown the PCI dma
689 mapping, you must call this function before doing so. At the next
690 point you give the PCI dma address back to the card, you must first
691 perform a pci_dma_sync_for_device, and then the device again owns
694 pci_dma_sync_single_for_cpu (struct pci_dev *pdev, dma_addr_t dma_addr, size_t size,
697 void *mb_sram_addr = PCI_TO_MB_SRAM (dma_addr);
698 struct dma_mapping *mapping = find_dma_mapping (mb_sram_addr);
700 /* Synchronize the DMA buffer with the CPU buffer if necessary. */
701 if (dir == PCI_DMA_FROMDEVICE)
702 memcpy (mapping->cpu_addr, mb_sram_addr, size);
703 else if (dir == PCI_DMA_TODEVICE)
704 ; /* nothing to do */
706 panic("pci_dma_sync_single: unsupported sync dir: %d", dir);
710 pci_dma_sync_single_for_device (struct pci_dev *pdev, dma_addr_t dma_addr, size_t size,
713 void *mb_sram_addr = PCI_TO_MB_SRAM (dma_addr);
714 struct dma_mapping *mapping = find_dma_mapping (mb_sram_addr);
716 /* Synchronize the DMA buffer with the CPU buffer if necessary. */
717 if (dir == PCI_DMA_FROMDEVICE)
718 ; /* nothing to do */
719 else if (dir == PCI_DMA_TODEVICE)
720 memcpy (mb_sram_addr, mapping->cpu_addr, size);
722 panic("pci_dma_sync_single: unsupported sync dir: %d", dir);
726 /* Scatter-gather PCI DMA mappings. */
728 /* Do multiple DMA mappings at once. */
730 pci_map_sg (struct pci_dev *pdev, struct scatterlist *sg, int sg_len, int dir)
736 /* Unmap multiple DMA mappings at once. */
738 pci_unmap_sg (struct pci_dev *pdev, struct scatterlist *sg, int sg_len,int dir)
743 /* Make physical memory consistent for a set of streaming mode DMA
744 translations after a transfer. The same as pci_dma_sync_single_* but
745 for a scatter-gather list, same rules and usage. */
748 pci_dma_sync_sg_for_cpu (struct pci_dev *dev, struct scatterlist *sg, int sg_len,
755 pci_dma_sync_sg_for_device (struct pci_dev *dev, struct scatterlist *sg, int sg_len,
762 /* PCI mem mapping. */
764 /* Allocate and map kernel buffer using consistent mode DMA for PCI
765 device. Returns non-NULL cpu-view pointer to the buffer if
766 successful and sets *DMA_ADDR to the pci side dma address as well,
767 else DMA_ADDR is undefined. */
769 pci_alloc_consistent (struct pci_dev *pdev, size_t size, dma_addr_t *dma_addr)
771 void *mb_sram_mem = alloc_mb_sram (size);
773 *dma_addr = MB_SRAM_TO_PCI (mb_sram_mem);
777 /* Free and unmap a consistent DMA buffer. CPU_ADDR and DMA_ADDR must
778 be values that were returned from pci_alloc_consistent. SIZE must be
779 the same as what as passed into pci_alloc_consistent. References to
780 the memory and mappings assosciated with CPU_ADDR or DMA_ADDR past
781 this call are illegal. */
783 pci_free_consistent (struct pci_dev *pdev, size_t size, void *cpu_addr,
786 void *mb_sram_mem = PCI_TO_MB_SRAM (dma_addr);
787 free_mb_sram (mb_sram_mem, size);
791 /* symbol exports (for modules) */
793 EXPORT_SYMBOL (pci_map_single);
794 EXPORT_SYMBOL (pci_unmap_single);
795 EXPORT_SYMBOL (pci_alloc_consistent);
796 EXPORT_SYMBOL (pci_free_consistent);
797 EXPORT_SYMBOL (pci_dma_sync_single_for_cpu);
798 EXPORT_SYMBOL (pci_dma_sync_single_for_device);