List PCI devices on boot

kernel/device/device.c

@@ -2,6 +2,7 @@
 #include <device/dos.h>
 #include <device/partdrv.h>
 #include <device/partitions.h>
+#include <device/pci.h>
 #include <device/ramdrv.h>
 #include <device/terminal.h>
 #include <devices.h>
@@ -188,5 +189,6 @@ void devices_init (void) {
 
 #if defined(__x86_64__)
   ps2kb_device_init ();
+  pci_init ();
 #endif
 }

kernel/device/pci.c

@@ -0,0 +1,124 @@
+#include <amd64/io.h>
+#include <device/pci.h>
+#include <libk/std.h>
+#include <sys/debug.h>
+
+static uint32_t pci_read32 (uint8_t bus, uint8_t slot, uint8_t func, uint8_t offset) {
+  uint32_t addr = (uint32_t)((uint32_t)bus << 16) | ((uint32_t)slot << 11) | ((uint32_t)func << 8) |
+      (offset & 0xFc) | ((uint32_t)0x80000000);
+  outl (PCI_CONFIG_ADDR, addr);
+  return inl (PCI_CONFIG_DATA);
+}
+
+static void pci_write32 (uint8_t bus, uint8_t slot, uint8_t func, uint8_t offset, uint32_t value) {
+  uint32_t addr = (uint32_t)((uint32_t)bus << 16) | ((uint32_t)slot << 11) | ((uint32_t)func << 8) |
+      (offset & 0xFc) | ((uint32_t)0x80000000);
+  outl (PCI_CONFIG_ADDR, addr);
+  outl (PCI_CONFIG_DATA, value);
+}
+
+static void pci_check_bus (uint8_t bus, pci_cb_func_t cb);
+
+static void pci_check_func (uint8_t bus, uint8_t slot, uint8_t func, pci_cb_func_t cb) {
+  uint32_t reg0 = pci_read32 (bus, slot, func, PCI_VENDOR_ID);
+  uint16_t vendor = (uint16_t)(reg0 & 0xFFFF);
+
+  if (vendor == 0xFFFF)
+    return;
+
+  uint32_t reg8 = pci_read32 (bus, slot, func, PCI_REVISION_ID);
+
+  struct pci_dev pci_dev = {
+      .bus = bus,
+      .slot = slot,
+      .func = func,
+      .vendor = vendor,
+      .device = ((uint16_t)(reg0 >> 16)),
+      .classcode = ((uint8_t)(reg8 >> 24)),
+      .subclass = ((uint8_t)(reg8 >> 16)),
+  };
+
+  cb (pci_dev);
+
+  /* PCI 2 PCI bridge */
+  if (pci_dev.classcode == 0x06 && pci_dev.subclass == 0x04) {
+    uint32_t reg18 = pci_read32 (bus, slot, func, 0x18);
+    uint8_t secondary = (uint8_t)(reg18 >> 8);
+    pci_check_bus (secondary, cb);
+  }
+}
+
+static void pci_check_device (uint8_t bus, uint8_t slot, pci_cb_func_t cb) {
+  uint32_t reg0 = pci_read32 (bus, slot, 0, PCI_VENDOR_ID);
+
+  if ((uint16_t)(reg0 & 0xFFFF) == 0xFFFF)
+    return;
+
+  pci_check_func (bus, slot, 0, cb);
+
+  /* multifunc device */
+  uint32_t reg0xc = pci_read32 (bus, slot, 0, PCI_CACHELINE);
+  if ((reg0xc >> 16) & 0x80) {
+    for (uint8_t func = 1; func < 8; func++)
+      pci_check_func (bus, slot, func, cb);
+  }
+}
+
+static void pci_check_bus (uint8_t bus, pci_cb_func_t cb) {
+  for (uint8_t slot = 0; slot < 32; slot++)
+    pci_check_device (bus, slot, cb);
+}
+
+static void pci_enumerate (pci_cb_func_t cb) {
+  uint32_t reg0xc = pci_read32 (0, 0, 0, PCI_CACHELINE);
+  bool is_multictrl = (reg0xc >> 16) & 0x80;
+
+  if (!is_multictrl)
+    pci_check_bus (0, cb);
+  else {
+    for (uint8_t func = 0; func < 8; func++) {
+      if ((pci_read32 (0, 0, func, PCI_VENDOR_ID) & 0xFFFF) != 0xFFFF)
+        pci_check_bus (func, cb);
+    }
+  }
+}
+
+static void pci_string_identifiers (uint16_t vendor_id, uint16_t device_id, uint8_t class_id,
+                                    uint8_t subclass_id, const char** vname, const char** dname,
+                                    const char** cname) {
+  *vname = "Unknown vendor";
+  *dname = "Unknown device";
+  *cname = "Unknown class";
+
+  for (size_t i = 0; pci_vendors[i].name; i++) {
+    if (pci_vendors[i].id == vendor_id) {
+      *vname = pci_vendors[i].name;
+      break;
+    }
+  }
+
+  for (size_t i = 0; pci_device_names[i].name; i++) {
+    if (pci_device_names[i].vendor_id == vendor_id && pci_device_names[i].device_id == device_id) {
+      *dname = pci_device_names[i].name;
+      break;
+    }
+  }
+
+  for (size_t i = 0; pci_classes[i].name; i++) {
+    if (pci_classes[i].class == class_id && pci_classes[i].subclass == subclass_id) {
+      *cname = pci_classes[i].name;
+      break;
+    }
+  }
+}
+
+static void pci_discovery_cb (struct pci_dev pci_dev) {
+  const char *vname, *dname, *cname;
+  pci_string_identifiers (pci_dev.vendor, pci_dev.device, pci_dev.classcode, pci_dev.subclass,
+                          &vname, &dname, &cname);
+
+  DEBUG ("PCI DEVICE: %04x:%04x at %02d:%02d:%02d / %s; %s; %s\n", pci_dev.vendor, pci_dev.device,
+         pci_dev.bus, pci_dev.slot, pci_dev.func, vname, dname, cname);
+}
+
+void pci_init (void) { pci_enumerate (&pci_discovery_cb); }

kernel/device/pci.h

@@ -0,0 +1,60 @@
+#ifndef _KERNEL_DEVICE_PCI_H
+#define _KERNEL_DEVICE_PCI_H
+
+#include <libk/std.h>
+
+#define PCI_CONFIG_ADDR 0xCF8
+#define PCI_CONFIG_DATA 0xCFC
+
+#define PCI_VENDOR_ID   0x00
+#define PCI_DEVICE_ID   0x02
+#define PCI_COMMAND     0x04
+#define PCI_STATUS      0x06
+#define PCI_REVISION_ID 0x08
+#define PCI_PROG_IF     0x09
+#define PCI_SUBCLASS    0x0A
+#define PCI_CLASS       0x0B
+#define PCI_CACHELINE   0x0C
+#define PCI_LATENCY     0x0D
+#define PCI_HEADER_TYPE 0x0E
+#define PCI_BIST        0x0F
+#define PCI_BAR0        0x10
+
+struct pci_dev {
+  uint8_t bus;
+  uint8_t slot;
+  uint8_t func;
+  uint16_t vendor;
+  uint16_t device;
+  uint8_t classcode;
+  uint8_t subclass;
+};
+
+struct pci_vendor {
+  uint16_t id;
+  const char* name;
+};
+
+struct pci_device_id {
+  uint16_t vendor_id;
+  uint16_t device_id;
+  const char* name;
+};
+
+struct pci_class {
+  uint8_t class;
+  uint8_t subclass;
+  const char* name;
+};
+
+typedef void (*pci_cb_func_t) (struct pci_dev pci_dev);
+
+void pci_init (void);
+
+extern const struct pci_vendor pci_vendors[];
+
+extern const struct pci_device_id pci_device_names[];
+
+extern const struct pci_class pci_classes[];
+
+#endif // _KERNEL_DEVICE_PCI_H

kernel/device/src.mk

@@ -11,6 +11,11 @@ o += device/device.o \
 		 device/partitions.o
 
 ifeq ($(platform),amd64)
-	c += device/ps2_kb.c
-	o += device/ps2_kb.o
+	c += device/ps2_kb.c \
+			 device/pci.c \
+			 device/pci_defs.c
+
+	o += device/ps2_kb.o \
+			 device/pci.o \
+			 device/pci_defs.o
 endif

kernel/generic/flags.mk

@@ -7,7 +7,8 @@ cflags += -nostdinc \
 					-pedantic-errors \
 					-Wall \
 					-Wextra \
-					-mcmodel=kernel
+					-mcmodel=kernel \
+					-Wno-trigraphs
 
 cflags += -isystem . -isystem ../include