diff options
Diffstat (limited to 'kernel/drivers/pci.c')
| -rw-r--r-- | kernel/drivers/pci.c | 142 |
1 files changed, 142 insertions, 0 deletions
diff --git a/kernel/drivers/pci.c b/kernel/drivers/pci.c new file mode 100644 index 0000000..9c16601 --- /dev/null +++ b/kernel/drivers/pci.c @@ -0,0 +1,142 @@ +// MIT License, Copyright (c) 2020 Marvin Borner + +#include <cpu.h> +#include <def.h> +#include <mem.h> +#include <pci.h> + +void pci_write_field(u32 device, int field, u32 value) +{ + outl(PCI_ADDRESS_PORT, pci_get_addr(device, field)); + outl(PCI_VALUE_PORT, value); +} + +u32 pci_read_field(u32 device, int field, int size) +{ + outl(PCI_ADDRESS_PORT, pci_get_addr(device, field)); + + if (size == 4) { + u32 t = inl(PCI_VALUE_PORT); + return t; + } else if (size == 2) { + u16 t = inw((u16)(PCI_VALUE_PORT + (field & 2))); + return t; + } else if (size == 1) { + u8 t = inb((u16)(PCI_VALUE_PORT + (field & 3))); + return t; + } + return 0xFFFF; +} + +u16 pci_find_type(u32 device) +{ + return (u16)((pci_read_field(device, PCI_CLASS, 1) << 8) | + pci_read_field(device, PCI_SUBCLASS, 1)); +} + +void pci_scan_hit(pci_func_t f, u32 dev, void *extra) +{ + int dev_vend = (int)pci_read_field(dev, PCI_VENDOR_ID, 2); + int dev_dvid = (int)pci_read_field(dev, PCI_DEVICE_ID, 2); + + f(dev, (u16)dev_vend, (u16)dev_dvid, extra); +} + +void pci_scan_func(pci_func_t f, int type, int bus, int slot, int func, void *extra) +{ + u32 dev = pci_box_device(bus, slot, func); + if (type == -1 || type == pci_find_type(dev)) + pci_scan_hit(f, dev, extra); + if (pci_find_type(dev) == PCI_TYPE_BRIDGE) + pci_scan_bus(f, type, (int)pci_read_field(dev, PCI_SECONDARY_BUS, 1), extra); +} + +void pci_scan_slot(pci_func_t f, int type, int bus, int slot, void *extra) +{ + u32 dev = pci_box_device(bus, slot, 0); + if (pci_read_field(dev, PCI_VENDOR_ID, 2) == PCI_NONE) + return; + pci_scan_func(f, type, bus, slot, 0, extra); + if (!pci_read_field(dev, PCI_HEADER_TYPE, 1)) + return; + for (int func = 1; func < 8; func++) { + dev = pci_box_device(bus, slot, func); + if (pci_read_field(dev, PCI_VENDOR_ID, 2) != PCI_NONE) + pci_scan_func(f, type, bus, slot, func, extra); + } +} + +void pci_scan_bus(pci_func_t f, int type, int bus, void *extra) +{ + for (int slot = 0; slot < 32; ++slot) + pci_scan_slot(f, type, bus, slot, extra); +} + +void pci_scan(pci_func_t f, int type, void *extra) +{ + if ((pci_read_field(0, PCI_HEADER_TYPE, 1) & 0x80) == 0) { + pci_scan_bus(f, type, 0, extra); + return; + } + + for (int func = 0; func < 8; ++func) { + u32 dev = pci_box_device(0, 0, func); + if (pci_read_field(dev, PCI_VENDOR_ID, 2) != PCI_NONE) + pci_scan_bus(f, type, func, extra); + else + break; + } +} + +static void find_isa_bridge(u32 device, u16 vendor_id, u16 device_id, void *extra) +{ + if (vendor_id == 0x8086 && (device_id == 0x7000 || device_id == 0x7110)) + *((u32 *)extra) = device; +} + +static u32 pci_isa = 0; +static u8 pci_remaps[4] = { 0 }; + +// Remap +void pci_install() +{ + pci_scan(&find_isa_bridge, -1, &pci_isa); + if (pci_isa) { + for (int i = 0; i < 4; ++i) { + pci_remaps[i] = (u8)pci_read_field(pci_isa, 0x60 + i, 1); + if (pci_remaps[i] == 0x80) { + pci_remaps[i] = (u8)(10 + (i % 1)); + } + } + u32 out = 0; + memcpy(&out, &pci_remaps, 4); + pci_write_field(pci_isa, 0x60, out); + } +} + +int pci_get_interrupt(u32 device) +{ + if (pci_isa) { + u32 irq_pin = pci_read_field(device, 0x3D, 1); + if (irq_pin == 0) + return (int)pci_read_field(device, PCI_INTERRUPT_LINE, 1); + int pirq = (int)(irq_pin + pci_extract_slot(device) - 2) % 4; + int int_line = (int)pci_read_field(device, PCI_INTERRUPT_LINE, 1); + + if (pci_remaps[pirq] >= 0x80) { + if (int_line == 0xFF) { + int_line = 10; + pci_write_field(device, PCI_INTERRUPT_LINE, (u32)int_line); + } + pci_remaps[pirq] = (u8)int_line; + u32 out = 0; + memcpy(&out, &pci_remaps, 4); + pci_write_field(pci_isa, 0x60, out); + return int_line; + } + pci_write_field(device, PCI_INTERRUPT_LINE, pci_remaps[pirq]); + return pci_remaps[pirq]; + } else { + return (int)pci_read_field(device, PCI_INTERRUPT_LINE, 1); + } +} |