pmc551.c

基于linux-2.6.28的mtd驱动

	 *
	 * KLUDGE ALERT: the boards we are using have invalid column and
	 * row mux values.  We fix them here, but this will break other
	 * memory configurations.
	 */
	pci_read_config_dword(dev, PMC551_DRAM_BLK0, &dram_data);
	size = PMC551_DRAM_BLK_GET_SIZE(dram_data);
	dram_data = PMC551_DRAM_BLK_SET_COL_MUX(dram_data, 0x5);
	dram_data = PMC551_DRAM_BLK_SET_ROW_MUX(dram_data, 0x9);
	pci_write_config_dword(dev, PMC551_DRAM_BLK0, dram_data);

	pci_read_config_dword(dev, PMC551_DRAM_BLK1, &dram_data);
	size += PMC551_DRAM_BLK_GET_SIZE(dram_data);
	dram_data = PMC551_DRAM_BLK_SET_COL_MUX(dram_data, 0x5);
	dram_data = PMC551_DRAM_BLK_SET_ROW_MUX(dram_data, 0x9);
	pci_write_config_dword(dev, PMC551_DRAM_BLK1, dram_data);

	pci_read_config_dword(dev, PMC551_DRAM_BLK2, &dram_data);
	size += PMC551_DRAM_BLK_GET_SIZE(dram_data);
	dram_data = PMC551_DRAM_BLK_SET_COL_MUX(dram_data, 0x5);
	dram_data = PMC551_DRAM_BLK_SET_ROW_MUX(dram_data, 0x9);
	pci_write_config_dword(dev, PMC551_DRAM_BLK2, dram_data);

	pci_read_config_dword(dev, PMC551_DRAM_BLK3, &dram_data);
	size += PMC551_DRAM_BLK_GET_SIZE(dram_data);
	dram_data = PMC551_DRAM_BLK_SET_COL_MUX(dram_data, 0x5);
	dram_data = PMC551_DRAM_BLK_SET_ROW_MUX(dram_data, 0x9);
	pci_write_config_dword(dev, PMC551_DRAM_BLK3, dram_data);

	/*
	 * Oops .. something went wrong
	 */
	if ((size &= PCI_BASE_ADDRESS_MEM_MASK) == 0) {
		return -ENODEV;
	}
#endif				/* CONFIG_MTD_PMC551_BUGFIX */

	if ((cfg & PCI_BASE_ADDRESS_SPACE) != PCI_BASE_ADDRESS_SPACE_MEMORY) {
		return -ENODEV;
	}

	/*
	 * Precharge Dram
	 */
	pci_write_config_word(dev, PMC551_SDRAM_MA, 0x0400);
	pci_write_config_word(dev, PMC551_SDRAM_CMD, 0x00bf);

	/*
	 * Wait until command has gone through
	 * FIXME: register spinning issue
	 */
	do {
		pci_read_config_word(dev, PMC551_SDRAM_CMD, &cmd);
		if (counter++ > 100)
			break;
	} while ((PCI_COMMAND_IO) & cmd);

	/*
	 * Turn on auto refresh
	 * The loop is taken directly from Ramix's example code.  I assume that
	 * this must be held high for some duration of time, but I can find no
	 * documentation refrencing the reasons why.
	 */
	for (i = 1; i <= 8; i++) {
		pci_write_config_word(dev, PMC551_SDRAM_CMD, 0x0df);

		/*
		 * Make certain command has gone through
		 * FIXME: register spinning issue
		 */
		counter = 0;
		do {
			pci_read_config_word(dev, PMC551_SDRAM_CMD, &cmd);
			if (counter++ > 100)
				break;
		} while ((PCI_COMMAND_IO) & cmd);
	}

	pci_write_config_word(dev, PMC551_SDRAM_MA, 0x0020);
	pci_write_config_word(dev, PMC551_SDRAM_CMD, 0x0ff);

	/*
	 * Wait until command completes
	 * FIXME: register spinning issue
	 */
	counter = 0;
	do {
		pci_read_config_word(dev, PMC551_SDRAM_CMD, &cmd);
		if (counter++ > 100)
			break;
	} while ((PCI_COMMAND_IO) & cmd);

	pci_read_config_dword(dev, PMC551_DRAM_CFG, &dcmd);
	dcmd |= 0x02000000;
	pci_write_config_dword(dev, PMC551_DRAM_CFG, dcmd);

	/*
	 * Check to make certain fast back-to-back, if not
	 * then set it so
	 */
	pci_read_config_word(dev, PCI_STATUS, &cmd);
	if ((cmd & PCI_COMMAND_FAST_BACK) == 0) {
		cmd |= PCI_COMMAND_FAST_BACK;
		pci_write_config_word(dev, PCI_STATUS, cmd);
	}

	/*
	 * Check to make certain the DEVSEL is set correctly, this device
	 * has a tendancy to assert DEVSEL and TRDY when a write is performed
	 * to the memory when memory is read-only
	 */
	if ((cmd & PCI_STATUS_DEVSEL_MASK) != 0x0) {
		cmd &= ~PCI_STATUS_DEVSEL_MASK;
		pci_write_config_word(dev, PCI_STATUS, cmd);
	}
	/*
	 * Set to be prefetchable and put everything back based on old cfg.
	 * it's possible that the reset of the V370PDC nuked the original
	 * setup
	 */
	/*
	   cfg |= PCI_BASE_ADDRESS_MEM_PREFETCH;
	   pci_write_config_dword( dev, PCI_BASE_ADDRESS_0, cfg );
	 */

	/*
	 * Turn PCI memory and I/O bus access back on
	 */
	pci_write_config_word(dev, PCI_COMMAND,
			      PCI_COMMAND_MEMORY | PCI_COMMAND_IO);
#ifdef CONFIG_MTD_PMC551_DEBUG
	/*
	 * Some screen fun
	 */
	printk(KERN_DEBUG "pmc551: %d%sB (0x%x) of %sprefetchable memory at "
		"0x%llx\n", (size < 1024) ? size : (size < 1048576) ?
		size >> 10 : size >> 20,
		(size < 1024) ? "" : (size < 1048576) ? "Ki" : "Mi", size,
		((dcmd & (0x1 << 3)) == 0) ? "non-" : "",
		(unsigned long long)pci_resource_start(dev, 0));

	/*
	 * Check to see the state of the memory
	 */
	pci_read_config_dword(dev, PMC551_DRAM_BLK0, &dcmd);
	printk(KERN_DEBUG "pmc551: DRAM_BLK0 Flags: %s,%s\n"
		"pmc551: DRAM_BLK0 Size: %d at %d\n"
		"pmc551: DRAM_BLK0 Row MUX: %d, Col MUX: %d\n",
		(((0x1 << 1) & dcmd) == 0) ? "RW" : "RO",
		(((0x1 << 0) & dcmd) == 0) ? "Off" : "On",
		PMC551_DRAM_BLK_GET_SIZE(dcmd),
		((dcmd >> 20) & 0x7FF), ((dcmd >> 13) & 0x7),
		((dcmd >> 9) & 0xF));

	pci_read_config_dword(dev, PMC551_DRAM_BLK1, &dcmd);
	printk(KERN_DEBUG "pmc551: DRAM_BLK1 Flags: %s,%s\n"
		"pmc551: DRAM_BLK1 Size: %d at %d\n"
		"pmc551: DRAM_BLK1 Row MUX: %d, Col MUX: %d\n",
		(((0x1 << 1) & dcmd) == 0) ? "RW" : "RO",
		(((0x1 << 0) & dcmd) == 0) ? "Off" : "On",
		PMC551_DRAM_BLK_GET_SIZE(dcmd),
		((dcmd >> 20) & 0x7FF), ((dcmd >> 13) & 0x7),
		((dcmd >> 9) & 0xF));

	pci_read_config_dword(dev, PMC551_DRAM_BLK2, &dcmd);
	printk(KERN_DEBUG "pmc551: DRAM_BLK2 Flags: %s,%s\n"
		"pmc551: DRAM_BLK2 Size: %d at %d\n"
		"pmc551: DRAM_BLK2 Row MUX: %d, Col MUX: %d\n",
		(((0x1 << 1) & dcmd) == 0) ? "RW" : "RO",
		(((0x1 << 0) & dcmd) == 0) ? "Off" : "On",
		PMC551_DRAM_BLK_GET_SIZE(dcmd),
		((dcmd >> 20) & 0x7FF), ((dcmd >> 13) & 0x7),
		((dcmd >> 9) & 0xF));

	pci_read_config_dword(dev, PMC551_DRAM_BLK3, &dcmd);
	printk(KERN_DEBUG "pmc551: DRAM_BLK3 Flags: %s,%s\n"
		"pmc551: DRAM_BLK3 Size: %d at %d\n"
		"pmc551: DRAM_BLK3 Row MUX: %d, Col MUX: %d\n",
		(((0x1 << 1) & dcmd) == 0) ? "RW" : "RO",
		(((0x1 << 0) & dcmd) == 0) ? "Off" : "On",
		PMC551_DRAM_BLK_GET_SIZE(dcmd),
		((dcmd >> 20) & 0x7FF), ((dcmd >> 13) & 0x7),
		((dcmd >> 9) & 0xF));

	pci_read_config_word(dev, PCI_COMMAND, &cmd);
	printk(KERN_DEBUG "pmc551: Memory Access %s\n",
		(((0x1 << 1) & cmd) == 0) ? "off" : "on");
	printk(KERN_DEBUG "pmc551: I/O Access %s\n",
		(((0x1 << 0) & cmd) == 0) ? "off" : "on");

	pci_read_config_word(dev, PCI_STATUS, &cmd);
	printk(KERN_DEBUG "pmc551: Devsel %s\n",
		((PCI_STATUS_DEVSEL_MASK & cmd) == 0x000) ? "Fast" :
		((PCI_STATUS_DEVSEL_MASK & cmd) == 0x200) ? "Medium" :
		((PCI_STATUS_DEVSEL_MASK & cmd) == 0x400) ? "Slow" : "Invalid");

	printk(KERN_DEBUG "pmc551: %sFast Back-to-Back\n",
		((PCI_COMMAND_FAST_BACK & cmd) == 0) ? "Not " : "");

	pci_read_config_byte(dev, PMC551_SYS_CTRL_REG, &bcmd);
	printk(KERN_DEBUG "pmc551: EEPROM is under %s control\n"
		"pmc551: System Control Register is %slocked to PCI access\n"
		"pmc551: System Control Register is %slocked to EEPROM access\n",
		(bcmd & 0x1) ? "software" : "hardware",
		(bcmd & 0x20) ? "" : "un", (bcmd & 0x40) ? "" : "un");
#endif
	return size;
}

/*
 * Kernel version specific module stuffages
 */

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Mark Ferrell <[e-mail]>");
MODULE_DESCRIPTION(PMC551_VERSION);

/*
 * Stuff these outside the ifdef so as to not bust compiled in driver support
 */
static int msize = 0;
static int asize = 0;

module_param(msize, int, 0);
MODULE_PARM_DESC(msize, "memory size in MiB [1 - 1024]");
module_param(asize, int, 0);
MODULE_PARM_DESC(asize, "aperture size, must be <= memsize [1-1024]");

/*
 * PMC551 Card Initialization
 */
static int __init init_pmc551(void)
{
	struct pci_dev *PCI_Device = NULL;
	struct mypriv *priv;
	int count, found = 0;
	struct mtd_info *mtd;
	u32 length = 0;

	if (msize) {
		msize = (1 << (ffs(msize) - 1)) << 20;
		if (msize > (1 << 30)) {
			printk(KERN_NOTICE "pmc551: Invalid memory size [%d]\n",
				msize);
			return -EINVAL;
		}
	}

	if (asize) {
		asize = (1 << (ffs(asize) - 1)) << 20;
		if (asize > (1 << 30)) {
			printk(KERN_NOTICE "pmc551: Invalid aperture size "
				"[%d]\n", asize);
			return -EINVAL;
		}
	}

	printk(KERN_INFO PMC551_VERSION);

	/*
	 * PCU-bus chipset probe.
	 */
	for (count = 0; count < MAX_MTD_DEVICES; count++) {

		if ((PCI_Device = pci_get_device(PCI_VENDOR_ID_V3_SEMI,
						  PCI_DEVICE_ID_V3_SEMI_V370PDC,
						  PCI_Device)) == NULL) {
			break;
		}

		printk(KERN_NOTICE "pmc551: Found PCI V370PDC at 0x%llx\n",
			(unsigned long long)pci_resource_start(PCI_Device, 0));

		/*
		 * The PMC551 device acts VERY weird if you don't init it
		 * first.  i.e. it will not correctly report devsel.  If for
		 * some reason the sdram is in a wrote-protected state the
		 * device will DEVSEL when it is written to causing problems
		 * with the oldproc.c driver in
		 * some kernels (2.2.*)
		 */
		if ((length = fixup_pmc551(PCI_Device)) <= 0) {
			printk(KERN_NOTICE "pmc551: Cannot init SDRAM\n");
			break;
		}

		/*
		 * This is needed until the driver is capable of reading the
		 * onboard I2C SROM to discover the "real" memory size.
		 */
		if (msize) {
			length = msize;
			printk(KERN_NOTICE "pmc551: Using specified memory "
				"size 0x%x\n", length);
		} else {
			msize = length;
		}

		mtd = kzalloc(sizeof(struct mtd_info), GFP_KERNEL);
		if (!mtd) {
			printk(KERN_NOTICE "pmc551: Cannot allocate new MTD "
				"device.\n");
			break;
		}

		priv = kzalloc(sizeof(struct mypriv), GFP_KERNEL);
		if (!priv) {
			printk(KERN_NOTICE "pmc551: Cannot allocate new MTD "
				"device.\n");
			kfree(mtd);
			break;
		}
		mtd->priv = priv;
		priv->dev = PCI_Device;

		if (asize > length) {
			printk(KERN_NOTICE "pmc551: reducing aperture size to "
				"fit %dM\n", length >> 20);
			priv->asize = asize = length;
		} else if (asize == 0 || asize == length) {
			printk(KERN_NOTICE "pmc551: Using existing aperture "
				"size %dM\n", length >> 20);
			priv->asize = asize = length;
		} else {
			printk(KERN_NOTICE "pmc551: Using specified aperture "
				"size %dM\n", asize >> 20);
			priv->asize = asize;
		}
		priv->start = pci_iomap(PCI_Device, 0, priv->asize);

		if (!priv->start) {
			printk(KERN_NOTICE "pmc551: Unable to map IO space\n");
			kfree(mtd->priv);
			kfree(mtd);
			break;
		}
#ifdef CONFIG_MTD_PMC551_DEBUG
		printk(KERN_DEBUG "pmc551: setting aperture to %d\n",
			ffs(priv->asize >> 20) - 1);
#endif

		priv->base_map0 = (PMC551_PCI_MEM_MAP_REG_EN
				   | PMC551_PCI_MEM_MAP_ENABLE
				   | (ffs(priv->asize >> 20) - 1) << 4);
		priv->curr_map0 = priv->base_map0;
		pci_write_config_dword(priv->dev, PMC551_PCI_MEM_MAP0,
					priv->curr_map0);

#ifdef CONFIG_MTD_PMC551_DEBUG
		printk(KERN_DEBUG "pmc551: aperture set to %d\n",
			(priv->base_map0 & 0xF0) >> 4);
#endif

		mtd->size = msize;
		mtd->flags = MTD_CAP_RAM;
		mtd->erase = pmc551_erase;
		mtd->read = pmc551_read;
		mtd->write = pmc551_write;
		mtd->point = pmc551_point;
		mtd->unpoint = pmc551_unpoint;
		mtd->type = MTD_RAM;
		mtd->name = "PMC551 RAM board";
		mtd->erasesize = 0x10000;
		mtd->writesize = 1;
		mtd->owner = THIS_MODULE;

		if (add_mtd_device(mtd)) {
			printk(KERN_NOTICE "pmc551: Failed to register new device\n");
			pci_iounmap(PCI_Device, priv->start);
			kfree(mtd->priv);
			kfree(mtd);
			break;
		}

		/* Keep a reference as the add_mtd_device worked */
		pci_dev_get(PCI_Device);

		printk(KERN_NOTICE "Registered pmc551 memory device.\n");
		printk(KERN_NOTICE "Mapped %dMiB of memory from 0x%p to 0x%p\n",
			priv->asize >> 20,
			priv->start, priv->start + priv->asize);
		printk(KERN_NOTICE "Total memory is %d%sB\n",
			(length < 1024) ? length :
			(length < 1048576) ? length >> 10 : length >> 20,
			(length < 1024) ? "" : (length < 1048576) ? "Ki" : "Mi");
		priv->nextpmc551 = pmc551list;
		pmc551list = mtd;
		found++;
	}

	/* Exited early, reference left over */
	if (PCI_Device)
		pci_dev_put(PCI_Device);

	if (!pmc551list) {
		printk(KERN_NOTICE "pmc551: not detected\n");
		return -ENODEV;
	} else {
		printk(KERN_NOTICE "pmc551: %d pmc551 devices loaded\n", found);
		return 0;
	}
}

/*
 * PMC551 Card Cleanup
 */
static void __exit cleanup_pmc551(void)
{
	int found = 0;
	struct mtd_info *mtd;
	struct mypriv *priv;

	while ((mtd = pmc551list)) {
		priv = mtd->priv;
		pmc551list = priv->nextpmc551;

		if (priv->start) {
			printk(KERN_DEBUG "pmc551: unmapping %dMiB starting at "
				"0x%p\n", priv->asize >> 20, priv->start);
			pci_iounmap(priv->dev, priv->start);
		}
		pci_dev_put(priv->dev);

		kfree(mtd->priv);
		del_mtd_device(mtd);
		kfree(mtd);
		found++;
	}

	printk(KERN_NOTICE "pmc551: %d pmc551 devices unloaded\n", found);
}

module_init(init_pmc551);
module_exit(cleanup_pmc551);