Re-implemented PCI driver.

Adding the affected files to the makefile doesn't work, though. This
probably has something to do with the 12KiB file size limit which should
have been fixed by now! I'll need to investigate this tomorrow.

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);
+	}
+}