1 files changed, 150 insertions, 0 deletions
diff --git a/src/pirq.c b/src/pirq.c
new file mode 100644
index 0000000..a342ac3
--- /dev/null
+++ b/src/pirq.c
@@ -0,0 +1,150 @@
+/*
+ * PCI IRQ Routing Table dumper
+ * Copyright (c) 2006 Dell, Inc.
+ *  by Matt Domsch <Matt_Domsch@dell.com>
+ *
+ * Based on the description of said table found at
+ * http://www.microsoft.com/hwdev/busbios/pciirq.htm
+ * Licensed under the GNU General Public license, version 2.
+ */
+
+#include <stdio.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <string.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <limits.h>
+#include <sys/mman.h>
+#include "pirq.h"
+
+/* If unknown, use INT_MAX so they get sorted last */
+int pirq_pci_dev_to_slot(struct routing_table *table, int bus, int dev)
+{
+	int i, num_slots;
+	struct slot_entry *slot;
+
+	if (!table)
+		return INT_MAX;
+
+	num_slots = (table->size - 32) / sizeof(*slot);
+	for (i=0; i<num_slots; i++) {
+		slot = &table->slot[i];
+		if (slot->bus == bus &&
+		    PCI_DEVICE(slot->device) == dev)
+			return slot->slot;
+	}
+	return INT_MAX;
+}
+
+
+
+struct routing_table * pirq_alloc_read_table()
+{
+	struct routing_table *table = NULL;
+	uint16_t size = 0;
+	uint8_t checksum = 0;
+	int i;
+	void *mem;
+	off_t offset=0L;
+	int fd=open("/dev/mem", O_RDONLY);
+
+	if(fd==-1)
+	{
+		perror("open(/dev/mem)");
+		return NULL;
+	}
+
+	mem = mmap(0, 64*1024, PROT_READ, MAP_SHARED, fd, 0xF0000L);
+	if (!mem) {
+		perror("mmap(/dev/mem)");
+		goto out;
+	}
+
+	while( offset < 0xFFFF)
+	{
+		if(memcmp(mem+offset, "$PIR", 4)==0)
+		{
+			table = (struct routing_table *)(mem+offset);
+			size = table->size;
+			/* quick sanity checks */
+			/* Version must be 1.0 */
+			if (! (table->version >> 8)==1 && 
+			      (table->version && 0xFF) == 0) break;
+
+			table = malloc(size);
+			if (!table) break;
+
+			memcpy(table, mem+offset, size);
+			for (i=0; i<size; i++)
+				checksum +=*(((uint8_t *)table)+i);
+			if (checksum) {
+				free (table);
+				table = NULL;
+			}
+			break;
+		}
+		offset += 16;
+	}
+	munmap(mem, 64*1024);
+out:
+	close(fd);
+	return table;
+}
+
+void pirq_free_table(struct routing_table *table)
+{
+	free(table);
+}
+
+
+#ifdef UNIT_TEST_PIRQ
+
+static void
+pirq_unparse_slot(struct slot_entry *slot)
+{
+	printf("Slot %d: PCI %x:%x. ",
+	       slot->slot, slot->bus, PCI_DEVICE(slot->device));
+	printf("INTA link %x irq %x ", slot->inta_link, slot->inta_irq);
+	printf("B link %x irq %x ", slot->intb_link, slot->intb_irq);
+	printf("C link %x irq %x ", slot->intc_link, slot->intc_irq);
+	printf("D link %x irq %x ", slot->intd_link, slot->intd_irq);
+	printf("\n");
+}
+
+static void
+pirq_unparse_routing_table(struct routing_table *table)
+{
+	int i, num_slots;
+	struct slot_entry *slot;
+	char buf[5]; buf[4] = 0;
+	memcpy(buf, &table->signature, 4);
+
+	printf("PCI IRQ Routing Table\n");
+	printf("Signature: %s\n", buf);
+	printf("Version  : %x\n", table->version);
+	printf("Size     : %xh\n", table->size);
+	printf("Bus      : %x\n", table->router_bus);
+	printf("DevFn    : %x\n", table->router_devfn);
+	printf("Exclusive IRQs : %x\n", table->exclusive_irqs);
+	printf("Compatable Router: %x\n", table->compatable_router);
+
+	num_slots = (table->size - 32) / sizeof(*slot);
+	slot = &table->slot[0];
+	for (i=0; i<num_slots; i++) {
+		pirq_unparse_slot(&slot[i]);
+	}
+}
+
+int main(int argc, char *argv[])
+{
+	struct routing_table *table;
+	table = pirq_alloc_read_table();
+	if (!table)
+		return 1;
+	pirq_unparse_routing_table(table);
+	pirq_free_table(table);
+	return 0;
+}
+
+#endif