1 files changed, 356 insertions, 0 deletions

diff --git a/arch/powerpc/sysdev/axonram.c b/arch/powerpc/sysdev/axonram.c
new file mode 100644
index 000000000..ee90db17b
--- /dev/null
+++ b/arch/powerpc/sysdev/axonram.c
@@ -0,0 +1,356 @@
+/*
+ * (C) Copyright IBM Deutschland Entwicklung GmbH 2006
+ *
+ * Author: Maxim Shchetynin <maxim@de.ibm.com>
+ *
+ * Axon DDR2 device driver.
+ * It registers one block device per Axon's DDR2 memory bank found on a system.
+ * Block devices are called axonram?, their major and minor numbers are
+ * available in /proc/devices, /proc/partitions or in /sys/block/axonram?/dev.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/bio.h>
+#include <linux/blkdev.h>
+#include <linux/device.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/genhd.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/ioport.h>
+#include <linux/irq.h>
+#include <linux/irqreturn.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/types.h>
+#include <linux/of_device.h>
+#include <linux/of_platform.h>
+
+#include <asm/page.h>
+#include <asm/prom.h>
+
+#define AXON_RAM_MODULE_NAME		"axonram"
+#define AXON_RAM_DEVICE_NAME		"axonram"
+#define AXON_RAM_MINORS_PER_DISK	16
+#define AXON_RAM_BLOCK_SHIFT		PAGE_SHIFT
+#define AXON_RAM_BLOCK_SIZE		1 << AXON_RAM_BLOCK_SHIFT
+#define AXON_RAM_SECTOR_SHIFT		9
+#define AXON_RAM_SECTOR_SIZE		1 << AXON_RAM_SECTOR_SHIFT
+#define AXON_RAM_IRQ_FLAGS		IRQF_SHARED | IRQF_TRIGGER_RISING
+
+static int azfs_major, azfs_minor;
+
+struct axon_ram_bank {
+	struct platform_device	*device;
+	struct gendisk		*disk;
+	unsigned int		irq_id;
+	unsigned long		ph_addr;
+	unsigned long		io_addr;
+	unsigned long		size;
+	unsigned long		ecc_counter;
+};
+
+static ssize_t
+axon_ram_sysfs_ecc(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct platform_device *device = to_platform_device(dev);
+	struct axon_ram_bank *bank = device->dev.platform_data;
+
+	BUG_ON(!bank);
+
+	return sprintf(buf, "%ld\n", bank->ecc_counter);
+}
+
+static DEVICE_ATTR(ecc, S_IRUGO, axon_ram_sysfs_ecc, NULL);
+
+/**
+ * axon_ram_irq_handler - interrupt handler for Axon RAM ECC
+ * @irq: interrupt ID
+ * @dev: pointer to of_device
+ */
+static irqreturn_t
+axon_ram_irq_handler(int irq, void *dev)
+{
+	struct platform_device *device = dev;
+	struct axon_ram_bank *bank = device->dev.platform_data;
+
+	BUG_ON(!bank);
+
+	dev_err(&device->dev, "Correctable memory error occurred\n");
+	bank->ecc_counter++;
+	return IRQ_HANDLED;
+}
+
+/**
+ * axon_ram_make_request - make_request() method for block device
+ * @queue, @bio: see blk_queue_make_request()
+ */
+static void
+axon_ram_make_request(struct request_queue *queue, struct bio *bio)
+{
+	struct axon_ram_bank *bank = bio->bi_bdev->bd_disk->private_data;
+	unsigned long phys_mem, phys_end;
+	void *user_mem;
+	struct bio_vec vec;
+	unsigned int transfered;
+	struct bvec_iter iter;
+
+	phys_mem = bank->io_addr + (bio->bi_iter.bi_sector <<
+				    AXON_RAM_SECTOR_SHIFT);
+	phys_end = bank->io_addr + bank->size;
+	transfered = 0;
+	bio_for_each_segment(vec, bio, iter) {
+		if (unlikely(phys_mem + vec.bv_len > phys_end)) {
+			bio_io_error(bio);
+			return;
+		}
+
+		user_mem = page_address(vec.bv_page) + vec.bv_offset;
+		if (bio_data_dir(bio) == READ)
+			memcpy(user_mem, (void *) phys_mem, vec.bv_len);
+		else
+			memcpy((void *) phys_mem, user_mem, vec.bv_len);
+
+		phys_mem += vec.bv_len;
+		transfered += vec.bv_len;
+	}
+	bio_endio(bio, 0);
+}
+
+/**
+ * axon_ram_direct_access - direct_access() method for block device
+ * @device, @sector, @data: see block_device_operations method
+ */
+static long
+axon_ram_direct_access(struct block_device *device, sector_t sector,
+		       void **kaddr, unsigned long *pfn, long size)
+{
+	struct axon_ram_bank *bank = device->bd_disk->private_data;
+	loff_t offset = (loff_t)sector << AXON_RAM_SECTOR_SHIFT;
+
+	*kaddr = (void *)(bank->ph_addr + offset);
+	*pfn = virt_to_phys(*kaddr) >> PAGE_SHIFT;
+
+	return bank->size - offset;
+}
+
+static const struct block_device_operations axon_ram_devops = {
+	.owner		= THIS_MODULE,
+	.direct_access	= axon_ram_direct_access
+};
+
+/**
+ * axon_ram_probe - probe() method for platform driver
+ * @device: see platform_driver method
+ */
+static int axon_ram_probe(struct platform_device *device)
+{
+	static int axon_ram_bank_id = -1;
+	struct axon_ram_bank *bank;
+	struct resource resource;
+	int rc = 0;
+
+	axon_ram_bank_id++;
+
+	dev_info(&device->dev, "Found memory controller on %s\n",
+			device->dev.of_node->full_name);
+
+	bank = kzalloc(sizeof(struct axon_ram_bank), GFP_KERNEL);
+	if (bank == NULL) {
+		dev_err(&device->dev, "Out of memory\n");
+		rc = -ENOMEM;
+		goto failed;
+	}
+
+	device->dev.platform_data = bank;
+
+	bank->device = device;
+
+	if (of_address_to_resource(device->dev.of_node, 0, &resource) != 0) {
+		dev_err(&device->dev, "Cannot access device tree\n");
+		rc = -EFAULT;
+		goto failed;
+	}
+
+	bank->size = resource_size(&resource);
+
+	if (bank->size == 0) {
+		dev_err(&device->dev, "No DDR2 memory found for %s%d\n",
+				AXON_RAM_DEVICE_NAME, axon_ram_bank_id);
+		rc = -ENODEV;
+		goto failed;
+	}
+
+	dev_info(&device->dev, "Register DDR2 memory device %s%d with %luMB\n",
+			AXON_RAM_DEVICE_NAME, axon_ram_bank_id, bank->size >> 20);
+
+	bank->ph_addr = resource.start;
+	bank->io_addr = (unsigned long) ioremap_prot(
+			bank->ph_addr, bank->size, _PAGE_NO_CACHE);
+	if (bank->io_addr == 0) {
+		dev_err(&device->dev, "ioremap() failed\n");
+		rc = -EFAULT;
+		goto failed;
+	}
+
+	bank->disk = alloc_disk(AXON_RAM_MINORS_PER_DISK);
+	if (bank->disk == NULL) {
+		dev_err(&device->dev, "Cannot register disk\n");
+		rc = -EFAULT;
+		goto failed;
+	}
+
+	bank->disk->major = azfs_major;
+	bank->disk->first_minor = azfs_minor;
+	bank->disk->fops = &axon_ram_devops;
+	bank->disk->private_data = bank;
+	bank->disk->driverfs_dev = &device->dev;
+
+	sprintf(bank->disk->disk_name, "%s%d",
+			AXON_RAM_DEVICE_NAME, axon_ram_bank_id);
+
+	bank->disk->queue = blk_alloc_queue(GFP_KERNEL);
+	if (bank->disk->queue == NULL) {
+		dev_err(&device->dev, "Cannot register disk queue\n");
+		rc = -EFAULT;
+		goto failed;
+	}
+
+	set_capacity(bank->disk, bank->size >> AXON_RAM_SECTOR_SHIFT);
+	blk_queue_make_request(bank->disk->queue, axon_ram_make_request);
+	blk_queue_logical_block_size(bank->disk->queue, AXON_RAM_SECTOR_SIZE);
+	add_disk(bank->disk);
+
+	bank->irq_id = irq_of_parse_and_map(device->dev.of_node, 0);
+	if (bank->irq_id == NO_IRQ) {
+		dev_err(&device->dev, "Cannot access ECC interrupt ID\n");
+		rc = -EFAULT;
+		goto failed;
+	}
+
+	rc = request_irq(bank->irq_id, axon_ram_irq_handler,
+			AXON_RAM_IRQ_FLAGS, bank->disk->disk_name, device);
+	if (rc != 0) {
+		dev_err(&device->dev, "Cannot register ECC interrupt handler\n");
+		bank->irq_id = NO_IRQ;
+		rc = -EFAULT;
+		goto failed;
+	}
+
+	rc = device_create_file(&device->dev, &dev_attr_ecc);
+	if (rc != 0) {
+		dev_err(&device->dev, "Cannot create sysfs file\n");
+		rc = -EFAULT;
+		goto failed;
+	}
+
+	azfs_minor += bank->disk->minors;
+
+	return 0;
+
+failed:
+	if (bank != NULL) {
+		if (bank->irq_id != NO_IRQ)
+			free_irq(bank->irq_id, device);
+		if (bank->disk != NULL) {
+			if (bank->disk->major > 0)
+				unregister_blkdev(bank->disk->major,
+						bank->disk->disk_name);
+			del_gendisk(bank->disk);
+		}
+		device->dev.platform_data = NULL;
+		if (bank->io_addr != 0)
+			iounmap((void __iomem *) bank->io_addr);
+		kfree(bank);
+	}
+
+	return rc;
+}
+
+/**
+ * axon_ram_remove - remove() method for platform driver
+ * @device: see of_platform_driver method
+ */
+static int
+axon_ram_remove(struct platform_device *device)
+{
+	struct axon_ram_bank *bank = device->dev.platform_data;
+
+	BUG_ON(!bank || !bank->disk);
+
+	device_remove_file(&device->dev, &dev_attr_ecc);
+	free_irq(bank->irq_id, device);
+	del_gendisk(bank->disk);
+	iounmap((void __iomem *) bank->io_addr);
+	kfree(bank);
+
+	return 0;
+}
+
+static const struct of_device_id axon_ram_device_id[] = {
+	{
+		.type	= "dma-memory"
+	},
+	{}
+};
+
+static struct platform_driver axon_ram_driver = {
+	.probe		= axon_ram_probe,
+	.remove		= axon_ram_remove,
+	.driver = {
+		.name = AXON_RAM_MODULE_NAME,
+		.of_match_table = axon_ram_device_id,
+	},
+};
+
+/**
+ * axon_ram_init
+ */
+static int __init
+axon_ram_init(void)
+{
+	azfs_major = register_blkdev(azfs_major, AXON_RAM_DEVICE_NAME);
+	if (azfs_major < 0) {
+		printk(KERN_ERR "%s cannot become block device major number\n",
+				AXON_RAM_MODULE_NAME);
+		return -EFAULT;
+	}
+	azfs_minor = 0;
+
+	return platform_driver_register(&axon_ram_driver);
+}
+
+/**
+ * axon_ram_exit
+ */
+static void __exit
+axon_ram_exit(void)
+{
+	platform_driver_unregister(&axon_ram_driver);
+	unregister_blkdev(azfs_major, AXON_RAM_DEVICE_NAME);
+}
+
+module_init(axon_ram_init);
+module_exit(axon_ram_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Maxim Shchetynin <maxim@de.ibm.com>");
+MODULE_DESCRIPTION("Axon DDR2 RAM device driver for IBM Cell BE");