/*
* bios32.c - PCI BIOS functions for m68k systems.
*
* Written by Wout Klaren.
*
* Based on the DEC Alpha bios32.c by Dave Rusling and David Mosberger.
*/
#include <linux/config.h>
#include <linux/init.h>
#include <linux/kernel.h>
#if 0
# define DBG_DEVS(args) printk args
#else
# define DBG_DEVS(args)
#endif
#ifdef CONFIG_PCI
/*
* PCI support for Linux/m68k. Currently only the Hades is supported.
*
* The support for PCI bridges in the DEC Alpha version has
* been removed in this version.
*/
#include <linux/pci.h>
#include <linux/slab.h>
#include <linux/mm.h>
#include <asm/io.h>
#include <asm/pci.h>
#include <asm/uaccess.h>
#define KB 1024
#define MB (1024*KB)
#define GB (1024*MB)
#define MAJOR_REV 0
#define MINOR_REV 5
/*
* Align VAL to ALIGN, which must be a power of two.
*/
#define ALIGN(val,align) (((val) + ((align) - 1)) & ~((align) - 1))
/*
* Offsets relative to the I/O and memory base addresses from where resources
* are allocated.
*/
#define IO_ALLOC_OFFSET 0x00004000
#define MEM_ALLOC_OFFSET 0x04000000
/*
* Declarations of hardware specific initialisation functions.
*/
extern struct pci_bus_info *init_hades_pci(void);
/*
* Bus info structure of the PCI bus. A pointer to this structure is
* put in the sysdata member of the pci_bus structure.
*/
static struct pci_bus_info *bus_info;
static int pci_modify = 1; /* If set, layout the PCI bus ourself. */
static int skip_vga; /* If set do not modify base addresses
of vga cards.*/
static int disable_pci_burst; /* If set do not allow PCI bursts. */
static unsigned int io_base;
static unsigned int mem_base;
/*
* static void disable_dev(struct pci_dev *dev)
*
* Disable PCI device DEV so that it does not respond to I/O or memory
* accesses.
*
* Parameters:
*
* dev - device to disable.
*/
static void __init disable_dev(struct pci_dev *dev)
{
unsigned short cmd;
if (((dev->class >> 8 == PCI_CLASS_NOT_DEFINED_VGA) ||
(dev->class >> 8 == PCI_CLASS_DISPLAY_VGA) ||
(dev->class >> 8 == PCI_CLASS_DISPLAY_XGA)) && skip_vga)
return;
pci_read_config_word(dev, PCI_COMMAND, &cmd);
cmd &= (~PCI_COMMAND_IO & ~PCI_COMMAND_MEMORY & ~PCI_COMMAND_MASTER);
pci_write_config_word(dev, PCI_COMMAND, cmd);
}
/*
* static void layout_dev(struct pci_dev *dev)
*
* Layout memory and I/O for a device.
*
* Parameters:
*
* device - device to layout memory and I/O for.
*/
static void __init layout_dev(struct pci_dev *dev)
{
unsigned short cmd;
unsigned int base, mask, size, reg;
unsigned int alignto;
int i;
/*
* Skip video cards if requested.
*/
if (((dev->class >> 8 == PCI_CLASS_NOT_DEFINED_VGA) ||
(dev->class >> 8 == PCI_CLASS_DISPLAY_VGA) ||
(dev->class >> 8 == PCI_CLASS_DISPLAY_XGA)) && skip_vga)
return;
pci_read_config_word(dev, PCI_COMMAND, &cmd);
for (reg = PCI_BASE_ADDRESS_0, i = 0; reg <= PCI_BASE_ADDRESS_5; reg += 4, i++)
{
/*
* Figure out how much space and of what type this
* device wants.
*/
pci_write_config_dword(dev, reg, 0xffffffff);
pci_read_config_dword(dev, reg, &base);
if (!base)
{
/* this base-address register is unused */
dev->resource[i].start = 0;
dev->resource[i].end = 0;
dev->resource[i].flags = 0;
continue;
}
/*
* We've read the base address register back after
* writing all ones and so now we must decode it.
*/
if (base & PCI_BASE_ADDRESS_SPACE_IO)
{
/*
* I/O space base address register.
*/
cmd |= PCI_COMMAND_IO;
base &= PCI_BASE_ADDRESS_IO_MASK;
mask = (~base << 1) | 0x1;
size = (mask & base) & 0xffffffff;
/*
* Align to multiple of size of minimum base.
*/
alignto = max_t(unsigned int, 0x040, size);
base = ALIGN(io_base, alignto);
io_base = base + size;
pci_write_config_dword(dev, reg, base | PCI_BASE_ADDRESS_SPACE_IO);
dev->resource[i].start = base;
dev->resource[i].end = dev->resource[i].start + size - 1;
dev->resource[i].flags = IORESOURCE_IO | PCI_BASE_ADDRESS_SPACE_IO;
DBG_DEVS(("layout_dev: IO address: %lX\n", base));
}
else
{
unsigned int type;
/*
* Memory space base address register.
*/
cmd |= PCI_COMMAND_MEMORY;
type = base & PCI_BASE_ADDRESS_MEM_TYPE_MASK;
base &= PCI_BASE_ADDRESS_MEM_MASK;
mask = (~base << 1) | 0x1;
size = (mask & base) & 0xffffffff;
switch (type)
{
case PCI_BASE_ADDRESS_MEM_TYPE_32:
case PCI_BASE_ADDRESS_MEM_TYPE_64:
break;
case PCI_BASE_ADDRESS_MEM_TYPE_1M:
printk("bios32 WARNING: slot %d, function %d "
"requests memory below 1MB---don't "
"know how to do that.\n",
PCI_SLOT(dev->devfn),
PCI_FUNC(dev->devfn));
continue;
}
/*
* Align to multiple of size of minimum base.
*/
alignto = max_t(unsigned int, 0x1000, size);
base = ALIGN(mem_base, alignto);
mem_base = base + size;
pci_write_config_dword(dev, reg, base);
dev->resource[i].start = base;
dev->resource[i].end = dev->resource[i].start + size - 1;
dev->resource[i].flags = IORESOURCE_MEM;
if (type == PCI_BASE_ADDRESS_MEM_TYPE_64)
{
/*
* 64-bit address, set the highest 32 bits
* to zero.
*/
reg += 4;
pci_write_config_dword(dev, reg, 0);
i++;
dev->resource[i].start = 0;
dev->resource[i].end = 0;
dev->resource[i].flags = 0;
}
}
}
/*
* Enable device:
*/
if (dev->class >> 8 == PCI_CLASS_NOT_DEFINED ||
dev->class >> 8 == PCI_CLASS_NOT_DEFINED_VGA ||
dev->class >> 8 == PCI_CLASS_DISPLAY_VGA ||
dev->class >> 8 == PCI_CLASS_DISPLAY_XGA)
{
/*
* All of these (may) have I/O scattered all around
* and may not use i/o-base address registers at all.
* So we just have to always enable I/O to these
* devices.
*/
cmd |= PCI_COMMAND_IO;
}
pci_write_config_word(dev, PCI_COMMAND, cmd | PCI_COMMAND_MASTER);
pci_write_config_byte(dev, PCI_LATENCY_TIMER, (disable_pci_burst) ? 0 : 32);
if (bus_info != NULL)
bus_info->conf_device(dev); /* Machine dependent configuration. */
DBG_DEVS(("layout_dev: bus %d slot 0x%x VID 0x%x DID 0x%x class 0x%x\n",
dev->bus->number, PCI_SLOT(dev->devfn), dev->vendor, dev->device, dev->class));
}
/*
* static void layout_bus(struct pci_bus *bus)
*
* Layout memory and I/O for all devices on the given bus.
*
* Parameters:
*
* bus - bus.
*/
static void __init layout_bus(struct pci_bus *bus)
{
unsigned int bio, bmem;
struct pci_dev *dev;
DBG_DEVS(("layout_bus: starting bus %d\n", bus->number));
if (!bus->devices && !bus->children)
return;
/*
* Align the current bases on appropriate boundaries (4K for
* IO and 1MB for memory).
*/
bio = io_base = ALIGN(io_base, 4*KB);
bmem = mem_base = ALIGN(mem_base, 1*MB);
/*
* PCI devices might have been setup by a PCI BIOS emulation
* running under TOS. In these cases there is a
* window during which two devices may have an overlapping
* address range. To avoid this causing trouble, we first
* turn off the I/O and memory address decoders for all PCI
* devices. They'll be re-enabled only once all address
* decoders are programmed consistently.
*/
DBG_DEVS(("layout_bus: disable_dev for bus %d\n", bus->number));
for (dev = bus->devices; dev; dev = dev->sibling)
{
if ((dev->class >> 16 != PCI_BASE_CLASS_BRIDGE) ||
(dev->class >> 8 == PCI_CLASS_BRIDGE_PCMCIA))
disable_dev(dev);
}
/*
* Allocate space to each device:
*/
DBG_DEVS(("layout_bus: starting bus %d devices\n", bus->number));
for (dev = bus->devices; dev; dev = dev->sibling)
{
if ((dev->class >> 16 != PCI_BASE_CLASS_BRIDGE) ||
(dev->class >> 8 == PCI_CLASS_BRIDGE_PCMCIA))
layout_dev(dev);
}
DBG_DEVS(("layout_bus: bus %d finished\n", bus->number));
}
/*
* static void pcibios_fixup(void)
*
* Layout memory and I/O of all devices on the PCI bus if 'pci_modify' is
* true. This might be necessary because not every m68k machine with a PCI
* bus has a PCI BIOS. This function should be called right after
* pci_scan_bus() in pcibios_init().
*/
static void __init pcibios_fixup(void)
{
if (pci_modify)
{
/*
* Set base addresses for allocation of I/O and memory space.
*/
io_base = bus_info->io_space.start + IO_ALLOC_OFFSET;
mem_base = bus_info->mem_space.start + MEM_ALLOC_OFFSET;
/*
* Scan the tree, allocating PCI memory and I/O space.
*/
layout_bus(pci_bus_b(pci_root.next));
}
/*
* Fix interrupt assignments, etc.
*/
bus_info->fixup(pci_modify);
}
/*
* static void pcibios_claim_resources(struct pci_bus *bus)
*
* Claim all resources that are assigned to devices on the given bus.
*
* Parameters:
*
* bus - bus.
*/
static void __init pcibios_claim_resources(struct pci_bus *bus)
{
struct pci_dev *dev;
int i;
while (bus)
{
for (dev = bus->devices; (dev != NULL); dev = dev->sibling)
{
for (i = 0; i < PCI_NUM_RESOURCES; i++)
{
struct resource *r = &dev->resource[i];
struct resource *pr;
struct pci_bus_info *bus_info = (struct pci_bus_info *) dev->sysdata;
if ((r->start == 0) || (r->parent != NULL))
continue;
#if 1
if (r->flags & IORESOURCE_IO)
pr = &bus_info->io_space;
else
pr = &bus_info->mem_space;
#else
if (r->flags & IORESOURCE_IO)
pr = &ioport_resource;
else
pr = &iomem_resource;
#endif
if (request_resource(pr, r) < 0)
{
printk(KERN_ERR "PCI: Address space collision on region %d of device %s\n", i, dev->name);
}
}
}
if (bus->children)
pcibios_claim_resources(bus->children);
bus = bus->next;
}
}
/*
* int pcibios_assign_resource(struct pci_dev *dev, int i)
*
* Assign a new address to a PCI resource.
*
* Parameters:
*
* dev - device.
* i - resource.
*
* Result: 0 if successful.
*/
int __init pcibios_assign_resource(struct pci_dev *dev, int i)
{
struct resource *r = &dev->resource[i];
struct resource *pr = pci_find_parent_resource(dev, r);
unsigned long size = r->end + 1;
if (!pr)
return -EINVAL;
if (r->flags & IORESOURCE_IO)
{
if (size > 0x100)
return -EFBIG;
if (allocate_resource(pr, r, size, bus_info->io_space.start +
IO_ALLOC_OFFSET, bus_info->io_space.end, 1024))
return -EBUSY;
}
else
{
if (allocate_resource(pr, r, size, bus_info->mem_space.start +
MEM_ALLOC_OFFSET, bus_info->mem_space.end, size))
return -EBUSY;
}
if (i < 6)
pci_write_config_dword(dev, PCI_BASE_ADDRESS_0 + 4 * i, r->start);
return 0;
}
void __init pcibios_fixup_bus(struct pci_bus *bus)
{
struct pci_dev *dev;
void *sysdata;
sysdata = (bus->parent) ? bus->parent->sysdata : bus->sysdata;
for (dev = bus->devices; (dev != NULL); dev = dev->sibling)
dev->sysdata = sysdata;
}
void __init pcibios_init(void)
{
printk("Linux/m68k PCI BIOS32 revision %x.%02x\n", MAJOR_REV, MINOR_REV);
bus_info = NULL;
#ifdef CONFIG_HADES
if (MACH_IS_HADES)
bus_info = init_hades_pci();
#endif
if (bus_info != NULL)
{
printk("PCI: Probing PCI hardware\n");
pci_scan_bus(0, bus_info->m68k_pci_ops, bus_info);
pcibios_fixup();
pcibios_claim_resources(pci_root);
}
else
printk("PCI: No PCI bus detected\n");
}
char * __init pcibios_setup(char *str)
{
if (!strcmp(str, "nomodify"))
{
pci_modify = 0;
return NULL;
}
else if (!strcmp(str, "skipvga"))
{
skip_vga = 1;
return NULL;
}
else if (!strcmp(str, "noburst"))
{
disable_pci_burst = 1;
return NULL;
}
return str;
}
#endif /* CONFIG_PCI */
