/*
 *	The PCI Library -- Generic Direct Access Functions
 *
 *	Copyright (c) 1997--2022 Martin Mares <mj@ucw.cz>
 *
 *	Can be freely distributed and used under the terms of the GNU GPL v2+.
 *
 *	SPDX-License-Identifier: GPL-2.0-or-later
 */

#include <string.h>

#include "internal.h"

void
pci_generic_scan_bus(struct pci_access *a, byte *busmap, int domain, int bus)
{
  int dev, multi, ht;
  struct pci_dev *t;

  a->debug("Scanning bus %02x for devices...\n", bus);
  if (busmap[bus])
    {
      a->warning("Bus %02x seen twice (firmware bug). Ignored.", bus);
      return;
    }
  busmap[bus] = 1;
  t = pci_alloc_dev(a);
  t->domain = domain;
  t->bus = bus;
  for (dev=0; dev<32; dev++)
    {
      t->dev = dev;
      multi = 0;
      for (t->func=0; !t->func || multi && t->func<8; t->func++)
	{
	  u32 vd = pci_read_long(t, PCI_VENDOR_ID);
	  struct pci_dev *d;

	  if (!vd || vd == 0xffffffff)
	    continue;
	  ht = pci_read_byte(t, PCI_HEADER_TYPE);
	  if (!t->func)
	    multi = ht & 0x80;
	  ht &= 0x7f;
	  d = pci_alloc_dev(a);
	  d->domain = t->domain;
	  d->bus = t->bus;
	  d->dev = t->dev;
	  d->func = t->func;
	  d->vendor_id = vd & 0xffff;
	  d->device_id = vd >> 16U;
	  d->known_fields = PCI_FILL_IDENT;
	  d->hdrtype = ht;
	  pci_link_dev(a, d);
	  switch (ht)
	    {
	    case PCI_HEADER_TYPE_NORMAL:
	      break;
	    case PCI_HEADER_TYPE_BRIDGE:
	    case PCI_HEADER_TYPE_CARDBUS:
	      pci_generic_scan_bus(a, busmap, domain, pci_read_byte(t, PCI_SECONDARY_BUS));
	      break;
	    default:
	      a->debug("Device %04x:%02x:%02x.%d has unknown header type %02x.\n", d->domain, d->bus, d->dev, d->func, ht);
	    }
	}
    }
  pci_free_dev(t);
}

void
pci_generic_scan_domain(struct pci_access *a, int domain)
{
  byte busmap[256];

  memset(busmap, 0, sizeof(busmap));
  pci_generic_scan_bus(a, busmap, domain, 0);
}

void
pci_generic_scan(struct pci_access *a)
{
  pci_generic_scan_domain(a, 0);
}

static int
get_hdr_type(struct pci_dev *d)
{
  if (d->hdrtype < 0)
    d->hdrtype = pci_read_byte(d, PCI_HEADER_TYPE) & 0x7f;
  return d->hdrtype;
}

void
pci_generic_fill_info(struct pci_dev *d, unsigned int flags)
{
  struct pci_access *a = d->access;
  struct pci_cap *cap;

  if (want_fill(d, flags, PCI_FILL_IDENT))
    {
      d->vendor_id = pci_read_word(d, PCI_VENDOR_ID);
      d->device_id = pci_read_word(d, PCI_DEVICE_ID);
    }

  if (want_fill(d, flags, PCI_FILL_CLASS))
    d->device_class = pci_read_word(d, PCI_CLASS_DEVICE);

  if (want_fill(d, flags, PCI_FILL_CLASS_EXT))
    {
      d->prog_if = pci_read_byte(d, PCI_CLASS_PROG);
      d->rev_id = pci_read_byte(d, PCI_REVISION_ID);
    }

  if (want_fill(d, flags, PCI_FILL_SUBSYS))
    {
      switch (get_hdr_type(d))
        {
        case PCI_HEADER_TYPE_NORMAL:
          d->subsys_vendor_id = pci_read_word(d, PCI_SUBSYSTEM_VENDOR_ID);
          d->subsys_id = pci_read_word(d, PCI_SUBSYSTEM_ID);
          break;
        case PCI_HEADER_TYPE_BRIDGE:
          cap = pci_find_cap(d, PCI_CAP_ID_SSVID, PCI_CAP_NORMAL);
          if (cap)
            {
              d->subsys_vendor_id = pci_read_word(d, cap->addr + PCI_SSVID_VENDOR);
              d->subsys_id = pci_read_word(d, cap->addr + PCI_SSVID_DEVICE);
            }
          break;
        case PCI_HEADER_TYPE_CARDBUS:
          d->subsys_vendor_id = pci_read_word(d, PCI_CB_SUBSYSTEM_VENDOR_ID);
          d->subsys_id = pci_read_word(d, PCI_CB_SUBSYSTEM_ID);
          break;
        default:
          clear_fill(d, PCI_FILL_SUBSYS);
        }
    }

  if (want_fill(d, flags, PCI_FILL_IRQ))
    d->irq = pci_read_byte(d, PCI_INTERRUPT_LINE);

  if (want_fill(d, flags, PCI_FILL_BASES))
    {
      int cnt = 0, i;
      memset(d->base_addr, 0, sizeof(d->base_addr));
      switch (get_hdr_type(d))
	{
	case PCI_HEADER_TYPE_NORMAL:
	  cnt = 6;
	  break;
	case PCI_HEADER_TYPE_BRIDGE:
	  cnt = 2;
	  break;
	case PCI_HEADER_TYPE_CARDBUS:
	  cnt = 1;
	  break;
	}
      if (cnt)
	{
	  for (i=0; i<cnt; i++)
	    {
	      u32 x = pci_read_long(d, PCI_BASE_ADDRESS_0 + i*4);
	      if (!x || x == (u32) ~0)
		continue;
	      if ((x & PCI_BASE_ADDRESS_SPACE) == PCI_BASE_ADDRESS_SPACE_IO)
		d->base_addr[i] = x;
	      else
		{
		  if ((x & PCI_BASE_ADDRESS_MEM_TYPE_MASK) != PCI_BASE_ADDRESS_MEM_TYPE_64)
		    d->base_addr[i] = x;
		  else if (i >= cnt-1)
		    a->warning("%04x:%02x:%02x.%d: Invalid 64-bit address seen for BAR %d.", d->domain, d->bus, d->dev, d->func, i);
		  else
		    {
		      u32 y = pci_read_long(d, PCI_BASE_ADDRESS_0 + (++i)*4);
#ifdef PCI_HAVE_64BIT_ADDRESS
		      d->base_addr[i-1] = x | (((pciaddr_t) y) << 32);
#else
		      if (y)
			a->warning("%04x:%02x:%02x.%d 64-bit device address ignored.", d->domain, d->bus, d->dev, d->func);
		      else
			d->base_addr[i-1] = x;
#endif
		    }
		}
	    }
	}
    }

  if (want_fill(d, flags, PCI_FILL_ROM_BASE))
    {
      int reg = 0;
      d->rom_base_addr = 0;
      switch (get_hdr_type(d))
	{
	case PCI_HEADER_TYPE_NORMAL:
	  reg = PCI_ROM_ADDRESS;
	  break;
	case PCI_HEADER_TYPE_BRIDGE:
	  reg = PCI_ROM_ADDRESS1;
	  break;
	}
      if (reg)
	{
	  u32 u = pci_read_long(d, reg);
	  if (u != 0xffffffff)
	    d->rom_base_addr = u;
	}
    }

  pci_scan_caps(d, flags);
}

static int
pci_generic_block_op(struct pci_dev *d, int pos, byte *buf, int len,
		 int (*r)(struct pci_dev *d, int pos, byte *buf, int len))
{
  if ((pos & 1) && len >= 1)
    {
      if (!r(d, pos, buf, 1))
	return 0;
      pos++; buf++; len--;
    }
  if ((pos & 3) && len >= 2)
    {
      if (!r(d, pos, buf, 2))
	return 0;
      pos += 2; buf += 2; len -= 2;
    }
  while (len >= 4)
    {
      if (!r(d, pos, buf, 4))
	return 0;
      pos += 4; buf += 4; len -= 4;
    }
  if (len >= 2)
    {
      if (!r(d, pos, buf, 2))
	return 0;
      pos += 2; buf += 2; len -= 2;
    }
  if (len && !r(d, pos, buf, 1))
    return 0;
  return 1;
}

int
pci_generic_block_read(struct pci_dev *d, int pos, byte *buf, int len)
{
  return pci_generic_block_op(d, pos, buf, len, d->access->methods->read);
}

int
pci_generic_block_write(struct pci_dev *d, int pos, byte *buf, int len)
{
  return pci_generic_block_op(d, pos, buf, len, d->access->methods->write);
}