devices/ccat/update.c
branchstable-1.5
changeset 2556 674fcdccc0f3
parent 2553 b0c2762a1a83
child 2559 a24ff468cb25
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/devices/ccat/update.c	Fri Apr 25 16:42:36 2014 +0200
@@ -0,0 +1,458 @@
+/**
+    Network Driver for Beckhoff CCAT communication controller
+    Copyright (C) 2014  Beckhoff Automation GmbH
+    Author: Patrick Bruenn <p.bruenn@beckhoff.com>
+
+    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 of the License, 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.,
+    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+*/
+
+#include <linux/fs.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/uaccess.h>
+#include "compat.h"
+#include "module.h"
+#include "print.h"
+#include "update.h"
+
+#define CCAT_DATA_IN_4 0x038
+#define CCAT_DATA_IN_N 0x7F0
+#define CCAT_DATA_OUT_4 0x030
+#define CCAT_DATA_BLOCK_SIZE (size_t)((CCAT_DATA_IN_N - CCAT_DATA_IN_4)/8)
+#define CCAT_WRITE_BLOCK_SIZE 128
+#define CCAT_FLASH_SIZE (size_t)0xE0000
+
+/**     FUNCTION_NAME            CMD,  CLOCKS          */
+#define CCAT_BULK_ERASE          0xE3, 8
+#define CCAT_GET_PROM_ID         0xD5, 40
+#define CCAT_READ_FLASH          0xC0, 32
+#define CCAT_READ_STATUS         0xA0, 16
+#define CCAT_WRITE_ENABLE        0x60, 8
+#define CCAT_WRITE_FLASH         0x40, 32
+
+/* from http://graphics.stanford.edu/~seander/bithacks.html#ReverseByteWith32Bits */
+#define SWAP_BITS(B) \
+	((((B) * 0x0802LU & 0x22110LU) | ((B) * 0x8020LU & 0x88440LU)) * 0x10101LU >> 16)
+
+/**
+ * struct update_buffer - keep track of a CCAT FPGA update
+ * @update: pointer to a valid ccat_update object
+ * @data: buffer used for write operations
+ * @size: number of bytes written to the data buffer, if 0 on ccat_update_release() no data will be written to FPGA
+ */
+struct update_buffer {
+	struct ccat_update *update;
+	char data[CCAT_FLASH_SIZE];
+	size_t size;
+};
+
+static void ccat_wait_status_cleared(void __iomem * const ioaddr);
+static int ccat_read_flash(void __iomem * const ioaddr, char __user * buf,
+			   uint32_t len, loff_t * off);
+static void ccat_write_flash(const struct update_buffer *const buf);
+static void ccat_update_cmd(void __iomem * const ioaddr, uint8_t cmd,
+			    uint16_t clocks);
+static void ccat_update_destroy(struct kref *ref);
+
+/**
+ * wait_until_busy_reset() - wait until the busy flag was reset
+ * @ioaddr: address of the CCAT Update function in PCI config space
+ */
+static inline void wait_until_busy_reset(void __iomem * const ioaddr)
+{
+	wmb();
+	while (ioread8(ioaddr + 1)) {
+		schedule();
+	}
+}
+
+static int ccat_update_open(struct inode *const i, struct file *const f)
+{
+	struct ccat_update *update =
+	    container_of(i->i_cdev, struct ccat_update, cdev);
+	struct update_buffer *buf;
+	kref_get(&update->refcount);
+	if (atomic_read(&update->refcount.refcount) > 2) {
+		kref_put(&update->refcount, ccat_update_destroy);
+		return -EBUSY;
+	}
+
+	buf = kzalloc(sizeof(*buf), GFP_KERNEL);
+	if (!buf) {
+		kref_put(&update->refcount, ccat_update_destroy);
+		return -ENOMEM;
+	}
+
+	buf->update = update;
+	f->private_data = buf;
+	return 0;
+}
+
+static int ccat_update_release(struct inode *const i, struct file *const f)
+{
+	const struct update_buffer *const buf = f->private_data;
+	struct ccat_update *const update = buf->update;
+	if (buf->size > 0) {
+		ccat_update_cmd(update->ioaddr, CCAT_WRITE_ENABLE);
+		ccat_update_cmd(update->ioaddr, CCAT_BULK_ERASE);
+		ccat_wait_status_cleared(update->ioaddr);
+		ccat_write_flash(buf);
+	}
+	kfree(f->private_data);
+	kref_put(&update->refcount, ccat_update_destroy);
+	return 0;
+}
+
+/**
+ * ccat_update_read() - Read CCAT configuration data from flash
+ * @f: file handle previously initialized with ccat_update_open()
+ * @buf: buffer in user space provided for our data
+ * @len: length of the user space buffer
+ * @off: current offset of our file operation
+ *
+ * Copies data from the CCAT FPGA's configuration flash to user space.
+ * Note that the size of the FPGA's firmware is not known exactly so it
+ * is very possible that the overall buffer ends with a lot of 0xff.
+ *
+ * Return: the number of bytes written, or 0 if EOF reached
+ */
+static ssize_t ccat_update_read(struct file *const f, char __user * buf,
+				size_t len, loff_t * off)
+{
+	struct update_buffer *update = f->private_data;
+	if (!buf || !off) {
+		return -EINVAL;
+	}
+	if (*off >= CCAT_FLASH_SIZE) {
+		return 0;
+	}
+	if (*off + len >= CCAT_FLASH_SIZE) {
+		len = CCAT_FLASH_SIZE - *off;
+	}
+	return ccat_read_flash(update->update->ioaddr, buf, len, off);
+}
+
+/**
+ * ccat_update_write() - Write data to the CCAT FPGA's configuration flash
+ * @f: file handle previously initialized with ccat_update_open()
+ * @buf: buffer in user space providing the new configuration data (from *.rbf)
+ * @len: length of the user space buffer
+ * @off: current offset in the configuration data
+ *
+ * Copies data from user space (possibly a *.rbf) to the CCAT FPGA's
+ * configuration flash to user space.
+ *
+ * Return: the number of bytes written, or 0 if flash end is reached
+ */
+
+static ssize_t ccat_update_write(struct file *const f, const char __user * buf,
+				 size_t len, loff_t * off)
+{
+	struct update_buffer *const update = f->private_data;
+	if (*off + len > sizeof(update->data))
+		return 0;
+
+	copy_from_user(update->data + *off, buf, len);
+	*off += len;
+	update->size = *off;
+	return len;
+}
+
+static struct file_operations update_ops = {
+	.owner = THIS_MODULE,
+	.open = ccat_update_open,
+	.release = ccat_update_release,
+	.read = ccat_update_read,
+	.write = ccat_update_write,
+};
+
+/**
+ * __ccat_update_cmd() - Helper to issue a FPGA flash command
+ * @ioaddr: address of the CCAT Update function in PCI config space
+ * @cmd: the command identifier
+ * @clocks: the number of clocks associated with the specified command
+ *
+ * no write memory barrier is called and the busy flag is not evaluated
+ */
+static inline void __ccat_update_cmd(void __iomem * const ioaddr, uint8_t cmd,
+				     uint16_t clocks)
+{
+	iowrite8((0xff00 & clocks) >> 8, ioaddr);
+	iowrite8(0x00ff & clocks, ioaddr + 0x8);
+	iowrite8(cmd, ioaddr + 0x10);
+}
+
+/**
+ * ccat_update_cmd() - Helper to issue a FPGA flash command
+ * @ioaddr: address of the CCAT Update function in PCI config space
+ * @cmd: the command identifier
+ * @clocks: the number of clocks associated with the specified command
+ *
+ * Triggers a full flash command cycle with write memory barrier and
+ * command activate. This call blocks until the busy flag is reset.
+ */
+static inline void ccat_update_cmd(void __iomem * const ioaddr, uint8_t cmd,
+				   uint16_t clocks)
+{
+	__ccat_update_cmd(ioaddr, cmd, clocks);
+	wmb();
+	iowrite8(0xff, ioaddr + 0x7f8);
+	wait_until_busy_reset(ioaddr);
+}
+
+/**
+ * ccat_update_cmd_addr() - Helper to issue a FPGA flash command with address parameter
+ * @ioaddr: address of the CCAT Update function in PCI config space
+ * @cmd: the command identifier
+ * @clocks: the number of clocks associated with the specified command
+ * @addr: 24 bit address associated with the specified command
+ *
+ * Triggers a full flash command cycle with write memory barrier and
+ * command activate. This call blocks until the busy flag is reset.
+ */
+static inline void ccat_update_cmd_addr(void __iomem * const ioaddr,
+					uint8_t cmd, uint16_t clocks,
+					uint32_t addr)
+{
+	const uint8_t addr_0 = SWAP_BITS(addr & 0xff);
+	const uint8_t addr_1 = SWAP_BITS((addr & 0xff00) >> 8);
+	const uint8_t addr_2 = SWAP_BITS((addr & 0xff0000) >> 16);
+	__ccat_update_cmd(ioaddr, cmd, clocks);
+	iowrite8(addr_2, ioaddr + 0x18);
+	iowrite8(addr_1, ioaddr + 0x20);
+	iowrite8(addr_0, ioaddr + 0x28);
+	wmb();
+	iowrite8(0xff, ioaddr + 0x7f8);
+	wait_until_busy_reset(ioaddr);
+}
+
+/**
+ * ccat_get_prom_id() - Read CCAT PROM ID
+ * @ioaddr: address of the CCAT Update function in PCI config space
+ *
+ * Return: the CCAT FPGA's PROM identifier
+ */
+uint8_t ccat_get_prom_id(void __iomem * const ioaddr)
+{
+	ccat_update_cmd(ioaddr, CCAT_GET_PROM_ID);
+	return ioread8(ioaddr + 0x38);
+}
+
+/**
+ * ccat_get_status() - Read CCAT Update status
+ * @ioaddr: address of the CCAT Update function in PCI config space
+ *
+ * Return: the current status of the CCAT Update function
+ */
+static uint8_t ccat_get_status(void __iomem * const ioaddr)
+{
+	ccat_update_cmd(ioaddr, CCAT_READ_STATUS);
+	return ioread8(ioaddr + 0x20);
+}
+
+/**
+ * ccat_wait_status_cleared() - wait until CCAT status is cleared
+ * @ioaddr: address of the CCAT Update function in PCI config space
+ *
+ * Blocks until bit 7 of the CCAT Update status is reset
+ */
+
+static void ccat_wait_status_cleared(void __iomem * const ioaddr)
+{
+	uint8_t status;
+	do {
+		status = ccat_get_status(ioaddr);
+	} while (status & (1 << 7));
+}
+
+/**
+ * ccat_read_flash_block() - Read a block of CCAT configuration data from flash
+ * @ioaddr: address of the CCAT Update function in PCI config space
+ * @addr: 24 bit address of the block to read
+ * @len: number of bytes to read from this block, len <= CCAT_DATA_BLOCK_SIZE
+ * @buf: output buffer in user space
+ *
+ * Copies one block of configuration data from the CCAT FPGA's flash to
+ * the user space buffer.
+ * Note that the size of the FPGA's firmware is not known exactly so it
+ * is very possible that the overall buffer ends with a lot of 0xff.
+ *
+ * Return: the number of bytes copied
+ */
+static int ccat_read_flash_block(void __iomem * const ioaddr,
+				 const uint32_t addr, const uint16_t len,
+				 char __user * const buf)
+{
+	uint16_t i;
+	const uint16_t clocks = 8 * len;
+	ccat_update_cmd_addr(ioaddr, CCAT_READ_FLASH + clocks, addr);
+	for (i = 0; i < len; i++) {
+		put_user(ioread8(ioaddr + CCAT_DATA_IN_4 + 8 * i), buf + i);
+	}
+	return len;
+}
+
+/**
+ * ccat_read_flash() - Read a chunk of CCAT configuration data from flash
+ * @ioaddr: address of the CCAT Update function in PCI config space
+ * @buf: output buffer in user space
+ * @len: number of bytes to read
+ * @off: offset in the configuration data
+ *
+ * Copies multiple blocks of configuration data from the CCAT FPGA's
+ * flash to the user space buffer.
+ *
+ * Return: the number of bytes copied
+ */
+static int ccat_read_flash(void __iomem * const ioaddr, char __user * buf,
+			   uint32_t len, loff_t * off)
+{
+	const loff_t start = *off;
+	while (len > CCAT_DATA_BLOCK_SIZE) {
+		*off +=
+		    ccat_read_flash_block(ioaddr, *off, CCAT_DATA_BLOCK_SIZE,
+					  buf);
+		buf += CCAT_DATA_BLOCK_SIZE;
+		len -= CCAT_DATA_BLOCK_SIZE;
+	}
+	*off += ccat_read_flash_block(ioaddr, *off, len, buf);
+	return *off - start;
+}
+
+/**
+ * ccat_write_flash_block() - Write a block of CCAT configuration data to flash
+ * @ioaddr: address of the CCAT Update function in PCI config space
+ * @addr: 24 bit start address in the CCAT FPGA's flash
+ * @len: number of bytes to write in this block, len <= CCAT_WRITE_BLOCK_SIZE
+ * @buf: input buffer
+ *
+ * Copies one block of configuration data to the CCAT FPGA's flash
+ *
+ * Return: the number of bytes copied
+ */
+static int ccat_write_flash_block(void __iomem * const ioaddr,
+				  const uint32_t addr, const uint16_t len,
+				  const char *const buf)
+{
+	const uint16_t clocks = 8 * len;
+	uint16_t i;
+	ccat_update_cmd(ioaddr, CCAT_WRITE_ENABLE);
+	for (i = 0; i < len; i++) {
+		iowrite8(buf[i], ioaddr + CCAT_DATA_OUT_4 + 8 * i);
+	}
+	ccat_update_cmd_addr(ioaddr, CCAT_WRITE_FLASH + clocks, addr);
+	ccat_wait_status_cleared(ioaddr);
+	return len;
+}
+
+/**
+ * ccat_write_flash() - Write a new CCAT configuration to FPGA's flash
+ * @update: a CCAT Update buffer containing the new FPGA configuration
+ */
+static void ccat_write_flash(const struct update_buffer *const update)
+{
+	const char *buf = update->data;
+	uint32_t off = 0;
+	size_t len = update->size;
+	while (len > CCAT_WRITE_BLOCK_SIZE) {
+		ccat_write_flash_block(update->update->ioaddr, off,
+				       (uint16_t) CCAT_WRITE_BLOCK_SIZE, buf);
+		off += CCAT_WRITE_BLOCK_SIZE;
+		buf += CCAT_WRITE_BLOCK_SIZE;
+		len -= CCAT_WRITE_BLOCK_SIZE;
+	}
+	ccat_write_flash_block(update->update->ioaddr, off, (uint16_t) len,
+			       buf);
+}
+
+/**
+ * ccat_update_init() - Initialize the CCAT Update function
+ */
+struct ccat_update *ccat_update_init(const struct ccat_device *const ccatdev,
+				     void __iomem * const addr)
+{
+	struct ccat_update *const update = kzalloc(sizeof(*update), GFP_KERNEL);
+	if (!update) {
+		return NULL;
+	}
+	kref_init(&update->refcount);
+	update->ioaddr = ccatdev->bar[0].ioaddr + ioread32(addr + 0x8);
+	memcpy_fromio(&update->info, addr, sizeof(update->info));
+	print_update_info(&update->info, update->ioaddr);
+
+	if (0x00 != update->info.nRevision) {
+		pr_warn("CCAT Update rev. %d not supported\n",
+			update->info.nRevision);
+		goto cleanup;
+	}
+
+	if (alloc_chrdev_region(&update->dev, 0, 1, DRV_NAME)) {
+		pr_warn("alloc_chrdev_region() failed\n");
+		goto cleanup;
+	}
+
+	update->class = class_create(THIS_MODULE, "ccat_update");
+	if (NULL == update->class) {
+		pr_warn("Create device class failed\n");
+		goto cleanup;
+	}
+
+	if (NULL ==
+	    device_create(update->class, NULL, update->dev, NULL,
+			  "ccat_update")) {
+		pr_warn("device_create() failed\n");
+		goto cleanup;
+	}
+
+	cdev_init(&update->cdev, &update_ops);
+	update->cdev.owner = THIS_MODULE;
+	update->cdev.ops = &update_ops;
+	if (cdev_add(&update->cdev, update->dev, 1)) {
+		pr_warn("add update device failed\n");
+		goto cleanup;
+	}
+	return update;
+cleanup:
+	kref_put(&update->refcount, ccat_update_destroy);
+	return NULL;
+}
+
+/**
+ * ccat_update_destroy() - Cleanup the CCAT Update function
+ * @ref: pointer to a struct kref embedded into a struct ccat_update, which we intend to destroy
+ *
+ * Retrieves the parent struct ccat_update and destroys it.
+ */
+static void ccat_update_destroy(struct kref *ref)
+{
+	struct ccat_update *update =
+	    container_of(ref, struct ccat_update, refcount);
+	cdev_del(&update->cdev);
+	device_destroy(update->class, update->dev);
+	class_destroy(update->class);
+	unregister_chrdev_region(update->dev, 1);
+	kfree(update);
+	pr_debug("%s(): done\n", __FUNCTION__);
+}
+
+/**
+ * ccat_update_remove() - Prepare the CCAT Update function for removal
+ */
+void ccat_update_remove(struct ccat_update *update)
+{
+	kref_put(&update->refcount, ccat_update_destroy);
+	pr_debug("%s(): done\n", __FUNCTION__);
+}