indirect_pci.c 4.4 KB

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  1. // SPDX-License-Identifier: GPL-2.0-or-later
  2. /*
  3. * Support for indirect PCI bridges.
  4. *
  5. * Copyright (C) 1998 Gabriel Paubert.
  6. */
  7. #include <linux/kernel.h>
  8. #include <linux/pci.h>
  9. #include <linux/delay.h>
  10. #include <linux/string.h>
  11. #include <linux/init.h>
  12. #include <asm/io.h>
  13. #include <asm/pci-bridge.h>
  14. #include <asm/machdep.h>
  15. int __indirect_read_config(struct pci_controller *hose,
  16. unsigned char bus_number, unsigned int devfn,
  17. int offset, int len, u32 *val)
  18. {
  19. volatile void __iomem *cfg_data;
  20. u8 cfg_type = 0;
  21. u32 bus_no, reg;
  22. if (hose->indirect_type & PPC_INDIRECT_TYPE_NO_PCIE_LINK) {
  23. if (bus_number != hose->first_busno)
  24. return PCIBIOS_DEVICE_NOT_FOUND;
  25. if (devfn != 0)
  26. return PCIBIOS_DEVICE_NOT_FOUND;
  27. }
  28. if (ppc_md.pci_exclude_device)
  29. if (ppc_md.pci_exclude_device(hose, bus_number, devfn))
  30. return PCIBIOS_DEVICE_NOT_FOUND;
  31. if (hose->indirect_type & PPC_INDIRECT_TYPE_SET_CFG_TYPE)
  32. if (bus_number != hose->first_busno)
  33. cfg_type = 1;
  34. bus_no = (bus_number == hose->first_busno) ?
  35. hose->self_busno : bus_number;
  36. if (hose->indirect_type & PPC_INDIRECT_TYPE_EXT_REG)
  37. reg = ((offset & 0xf00) << 16) | (offset & 0xfc);
  38. else
  39. reg = offset & 0xfc;
  40. if (hose->indirect_type & PPC_INDIRECT_TYPE_BIG_ENDIAN)
  41. out_be32(hose->cfg_addr, (0x80000000 | (bus_no << 16) |
  42. (devfn << 8) | reg | cfg_type));
  43. else
  44. out_le32(hose->cfg_addr, (0x80000000 | (bus_no << 16) |
  45. (devfn << 8) | reg | cfg_type));
  46. /*
  47. * Note: the caller has already checked that offset is
  48. * suitably aligned and that len is 1, 2 or 4.
  49. */
  50. cfg_data = hose->cfg_data + (offset & 3);
  51. switch (len) {
  52. case 1:
  53. *val = in_8(cfg_data);
  54. break;
  55. case 2:
  56. *val = in_le16(cfg_data);
  57. break;
  58. default:
  59. *val = in_le32(cfg_data);
  60. break;
  61. }
  62. return PCIBIOS_SUCCESSFUL;
  63. }
  64. int indirect_read_config(struct pci_bus *bus, unsigned int devfn,
  65. int offset, int len, u32 *val)
  66. {
  67. struct pci_controller *hose = pci_bus_to_host(bus);
  68. return __indirect_read_config(hose, bus->number, devfn, offset, len,
  69. val);
  70. }
  71. int indirect_write_config(struct pci_bus *bus, unsigned int devfn,
  72. int offset, int len, u32 val)
  73. {
  74. struct pci_controller *hose = pci_bus_to_host(bus);
  75. volatile void __iomem *cfg_data;
  76. u8 cfg_type = 0;
  77. u32 bus_no, reg;
  78. if (hose->indirect_type & PPC_INDIRECT_TYPE_NO_PCIE_LINK) {
  79. if (bus->number != hose->first_busno)
  80. return PCIBIOS_DEVICE_NOT_FOUND;
  81. if (devfn != 0)
  82. return PCIBIOS_DEVICE_NOT_FOUND;
  83. }
  84. if (ppc_md.pci_exclude_device)
  85. if (ppc_md.pci_exclude_device(hose, bus->number, devfn))
  86. return PCIBIOS_DEVICE_NOT_FOUND;
  87. if (hose->indirect_type & PPC_INDIRECT_TYPE_SET_CFG_TYPE)
  88. if (bus->number != hose->first_busno)
  89. cfg_type = 1;
  90. bus_no = (bus->number == hose->first_busno) ?
  91. hose->self_busno : bus->number;
  92. if (hose->indirect_type & PPC_INDIRECT_TYPE_EXT_REG)
  93. reg = ((offset & 0xf00) << 16) | (offset & 0xfc);
  94. else
  95. reg = offset & 0xfc;
  96. if (hose->indirect_type & PPC_INDIRECT_TYPE_BIG_ENDIAN)
  97. out_be32(hose->cfg_addr, (0x80000000 | (bus_no << 16) |
  98. (devfn << 8) | reg | cfg_type));
  99. else
  100. out_le32(hose->cfg_addr, (0x80000000 | (bus_no << 16) |
  101. (devfn << 8) | reg | cfg_type));
  102. /* suppress setting of PCI_PRIMARY_BUS */
  103. if (hose->indirect_type & PPC_INDIRECT_TYPE_SURPRESS_PRIMARY_BUS)
  104. if ((offset == PCI_PRIMARY_BUS) &&
  105. (bus->number == hose->first_busno))
  106. val &= 0xffffff00;
  107. /* Workaround for PCI_28 Errata in 440EPx/GRx */
  108. if ((hose->indirect_type & PPC_INDIRECT_TYPE_BROKEN_MRM) &&
  109. offset == PCI_CACHE_LINE_SIZE) {
  110. val = 0;
  111. }
  112. /*
  113. * Note: the caller has already checked that offset is
  114. * suitably aligned and that len is 1, 2 or 4.
  115. */
  116. cfg_data = hose->cfg_data + (offset & 3);
  117. switch (len) {
  118. case 1:
  119. out_8(cfg_data, val);
  120. break;
  121. case 2:
  122. out_le16(cfg_data, val);
  123. break;
  124. default:
  125. out_le32(cfg_data, val);
  126. break;
  127. }
  128. return PCIBIOS_SUCCESSFUL;
  129. }
  130. static struct pci_ops indirect_pci_ops =
  131. {
  132. .read = indirect_read_config,
  133. .write = indirect_write_config,
  134. };
  135. void setup_indirect_pci(struct pci_controller *hose, resource_size_t cfg_addr,
  136. resource_size_t cfg_data, u32 flags)
  137. {
  138. resource_size_t base = cfg_addr & PAGE_MASK;
  139. void __iomem *mbase;
  140. mbase = ioremap(base, PAGE_SIZE);
  141. hose->cfg_addr = mbase + (cfg_addr & ~PAGE_MASK);
  142. if ((cfg_data & PAGE_MASK) != base)
  143. mbase = ioremap(cfg_data & PAGE_MASK, PAGE_SIZE);
  144. hose->cfg_data = mbase + (cfg_data & ~PAGE_MASK);
  145. hose->ops = &indirect_pci_ops;
  146. hose->indirect_type = flags;
  147. }