#include <linux/module.h>
#include <linux/types.h>
#include <linux/pci.h>

#define DRIVER_NAME "dump_stuff"
#define PFX DRIVER_NAME ": "
#define BAR 0x90000000
#define SMRBASE 0x14
#define IMCH_TST2 0xf6
#define IMCH_TST2_SYSMMREN 6

static void dump_pci_config(struct pci_dev* dev)
{
	int i, j;
	u8 b;
	printk("   f  e  d  c  b  a  9  8  7  6  5  4  3  2  1  0");
	for (i = 0xf; i >= 0; i--) {
		printk("\n%01x", i);
		for (j = 0xf; j >= 0; j--) {
			pci_read_config_byte(dev, (i << 4) | j, &b);
			printk(" %02x", b);
		}
	}
	printk("\n");
}

static void dump_mmio(volatile void __iomem *start, int sz)
{
	int i, j;
	printk("     f  e  d  c  b  a  9  8  7  6  5  4  3  2  1  0");
	for (i = (sz >> 4); i >= 0; i--) {
		printk("\n%02x ", i);
		for (j = 0xf; j >= 0; j--)
			printk(" %02x", readb(start + (i << 4) + j));
	}
	printk("\n");
}

static int imch_probe(struct pci_dev *dev, const struct pci_device_id *id)
{
	u8 imch_tst2;
	int rc = 0;
	unsigned long base, size;
	void __iomem *mem;

	rc = pci_enable_device(dev);
	if (rc) {
		printk(PFX "Couldn't enable device\n");
		goto err_enable_device;
	}

	rc = pci_request_regions(dev, DRIVER_NAME);
	if (rc) {
		printk(PFX "Couldn't request regions\n");
		goto err_request_regions;
	}

	pci_read_config_byte(dev, IMCH_TST2, &imch_tst2);
	pci_write_config_byte(dev, IMCH_TST2, imch_tst2 |
					1 << IMCH_TST2_SYSMMREN);

	pci_write_config_dword(dev, SMRBASE, BAR);

	//base = pci_resource_start(dev, SMRBASE);
	//size = pci_resource_len(dev, SMRBASE);
	base = BAR;
	size = 0x298;
	mem = ioremap(base, size);
	if (!mem) {
		printk(PFX "Couldn't map memory (0x%08lx,%ld)\n", base, size);
		rc = -ENOMEM;
		goto err_ioremap;
	}


	printk("Dumping IMCH PCI config registers\n");
	dump_pci_config(dev);
	printk("Dumping SMRBASE registers\n");
	dump_mmio(mem, size);

	iounmap(mem);
err_ioremap:
	pci_release_regions(dev);
err_request_regions:
	pci_disable_device(dev);
err_enable_device:
	return rc;
}

static const struct pci_device_id dump_stuff_id_tbl[] = {
	{0x8086, 0x5020, PCI_ANY_ID, PCI_ANY_ID,}, /* EP80579 IMCH */
	{ },
};
MODULE_DEVICE_TABLE(pci, dump_stuff_id_tbl);

static struct pci_driver dump_stuff = {
	.name = "dump_stuff",
	.id_table = dump_stuff_id_tbl,
	.probe = imch_probe,
};

static int init_dump_stuff(void)
{
	return pci_register_driver(&dump_stuff);
}
module_init(init_dump_stuff);

static void exit_dump_stuff(void)
{
	pci_unregister_driver(&dump_stuff);
}
module_exit(exit_dump_stuff);