simplify code


git-svn-id: svn://svn.coreboot.org/coreboot/trunk@2012 2b7e53f0-3cfb-0310-b3e9-8179ed1497e1
diff --git a/src/cpu/emulation/qemu-i386/northbridge.c b/src/cpu/emulation/qemu-i386/northbridge.c
new file mode 100644
index 0000000..2f1f48f
--- /dev/null
+++ b/src/cpu/emulation/qemu-i386/northbridge.c
@@ -0,0 +1,134 @@
+#include <console/console.h>
+#include <arch/io.h>
+#include <stdint.h>
+#include <device/device.h>
+#include <device/pci.h>
+#include <stdlib.h>
+#include <string.h>
+#include <bitops.h>
+#include "chip.h"
+#include "northbridge.h"
+
+#define BRIDGE_IO_MASK (IORESOURCE_IO | IORESOURCE_MEM)
+
+static void pci_domain_read_resources(device_t dev)
+{
+	struct resource *resource;
+
+	/* Initialize the system wide io space constraints */
+	resource = new_resource(dev, IOINDEX_SUBTRACTIVE(0,0));
+	resource->limit = 0xffffUL;
+	resource->flags = IORESOURCE_IO | IORESOURCE_SUBTRACTIVE | IORESOURCE_ASSIGNED;
+
+	/* Initialize the system wide memory resources constraints */
+	resource = new_resource(dev, IOINDEX_SUBTRACTIVE(1,0));
+	resource->limit = 0xffffffffULL;
+	resource->flags = IORESOURCE_MEM | IORESOURCE_SUBTRACTIVE | IORESOURCE_ASSIGNED;
+}
+
+static void ram_resource(device_t dev, unsigned long index,
+	unsigned long basek, unsigned long sizek)
+{
+	struct resource *resource;
+
+	if (!sizek) {
+		return;
+	}
+	resource = new_resource(dev, index);
+	resource->base	= ((resource_t)basek) << 10;
+	resource->size	= ((resource_t)sizek) << 10;
+	resource->flags =  IORESOURCE_MEM | IORESOURCE_CACHEABLE | \
+		IORESOURCE_FIXED | IORESOURCE_STORED | IORESOURCE_ASSIGNED;
+}
+
+static void tolm_test(void *gp, struct device *dev, struct resource *new)
+{
+	struct resource **best_p = gp;
+	struct resource *best;
+	best = *best_p;
+	if (!best || (best->base > new->base)) {
+		best = new;
+	}
+	*best_p = best;
+}
+
+static uint32_t find_pci_tolm(struct bus *bus)
+{
+	struct resource *min;
+	uint32_t tolm;
+	min = 0;
+	search_bus_resources(bus, IORESOURCE_MEM, IORESOURCE_MEM, tolm_test, &min);
+	tolm = 0xffffffffUL;
+	if (min && tolm > min->base) {
+		tolm = min->base;
+	}
+	return tolm;
+}
+
+static void pci_domain_set_resources(device_t dev)
+{
+	device_t mc_dev;
+	uint32_t pci_tolm;
+	uint32_t idx;
+
+	pci_tolm = find_pci_tolm(&dev->link[0]);
+	mc_dev = dev->link[0].children;
+	if (mc_dev) {
+		unsigned long tomk, tolmk;
+		/* Hard code the Top of memory for now */
+		tomk = 65536;
+		/* Compute the top of Low memory */
+		tolmk = pci_tolm >> 10;
+		if (tolmk >= tomk) {
+			/* The PCI hole does not overlap memory.
+			 */
+			tolmk = tomk;
+		}
+		
+		/* Report the memory regions */
+		idx = 10;
+		ram_resource(dev, idx++, 0, 640);
+		ram_resource(dev, idx++, 768, tolmk - 768);
+		if (tomk > 4*1024*1024) {
+			ram_resource(dev, idx++, 4096*1024, tomk - 4*1024*1024);
+		}
+	}
+	assign_resources(&dev->link[0]);
+}
+
+static unsigned int pci_domain_scan_bus(device_t dev, unsigned int max)
+{
+	max = pci_scan_bus(&dev->link[0], PCI_DEVFN(0, 0), 0xff, max);
+	return max;
+}
+
+static struct device_operations pci_domain_ops = {
+	.read_resources	  = pci_domain_read_resources,
+	.set_resources	  = pci_domain_set_resources,
+	.enable_resources = enable_childrens_resources,
+	.init		  = 0,
+	.scan_bus	  = pci_domain_scan_bus,
+};  
+
+static void enable_dev(struct device *dev)
+{
+	/* Set the operations if it is a special bus type */
+	if (dev->path.type == DEVICE_PATH_PCI_DOMAIN) {
+		dev->ops = &pci_domain_ops;
+		pci_set_method(dev);
+	}
+}
+
+struct chip_operations cpu_emulation_qemu_i386_ops = {
+	CHIP_NAME("QEMU Northbridge")
+	.enable_dev = enable_dev,
+};
+
+void udelay(int usecs)
+{
+	int i;
+	for(i = 0; i < usecs; i++)
+		outb(i&0xff, 0x80);
+}
+
+