1 files changed, 288 insertions, 0 deletions
diff --git a/target/linux/ubicom32/files/drivers/uio/uio_ubicom32ring.c b/target/linux/ubicom32/files/drivers/uio/uio_ubicom32ring.c
new file mode 100644
index 000000000..654ac4ced
--- /dev/null
+++ b/target/linux/ubicom32/files/drivers/uio/uio_ubicom32ring.c
@@ -0,0 +1,288 @@
+/*
+ * drivers/uio/uio_ubicom32ring.c
+ *
+ * Userspace I/O platform driver for Ubicom32 ring buffers
+ *
+ * (C) Copyright 2009, Ubicom, Inc.
+ *
+ * This file is part of the Ubicom32 Linux Kernel Port.
+ *
+ * Based on uio_ubicom32ring.c by Magnus Damm
+ *
+ * The Ubicom32 Linux Kernel Port 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.
+ *
+ * The Ubicom32 Linux Kernel Port 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 the Ubicom32 Linux Kernel Port.  If not,
+ * see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/platform_device.h>
+#include <linux/uio_driver.h>
+#include <linux/spinlock.h>
+#include <linux/bitops.h>
+#include <linux/interrupt.h>
+#include <linux/stringify.h>
+
+#include <asm/ip5000.h>
+#include <asm/ubicom32ring.h>
+
+#define DRIVER_NAME "uio_ubicom32ring"
+
+struct uio_ubicom32ring_data {
+	struct uio_info			*uioinfo;
+
+	struct uio_ubicom32ring_regs	*regs;
+
+	/*
+	 * IRQ used to kick the ring buffer
+	 */
+	int				irq_tx;
+	int				irq_rx;
+
+	spinlock_t			lock;
+
+	unsigned long			flags;
+
+	char				name[0];
+};
+
+static irqreturn_t uio_ubicom32ring_handler(int irq, struct uio_info *dev_info)
+{
+	struct uio_ubicom32ring_data *priv = dev_info->priv;
+
+	/* Just disable the interrupt in the interrupt controller, and
+	 * remember the state so we can allow user space to enable it later.
+	 */
+
+	if (!test_and_set_bit(0, &priv->flags))
+		disable_irq_nosync(irq);
+
+	return IRQ_HANDLED;
+}
+
+static int uio_ubicom32ring_irqcontrol(struct uio_info *dev_info, s32 irq_on)
+{
+	struct uio_ubicom32ring_data *priv = dev_info->priv;
+	unsigned long flags;
+
+	/* Allow user space to enable and disable the interrupt
+	 * in the interrupt controller, but keep track of the
+	 * state to prevent per-irq depth damage.
+	 *
+	 * Serialize this operation to support multiple tasks.
+	 */
+
+	spin_lock_irqsave(&priv->lock, flags);
+
+	if (irq_on & 2) {
+		/*
+		 * Kick the ring buffer (if we can)
+		 */
+		if (priv->irq_tx != 0xFF) {
+			ubicom32_set_interrupt(priv->irq_tx);
+		}
+	}
+
+	if (priv->irq_rx != 0xFF) {
+		if (irq_on & 1) {
+			if (test_and_clear_bit(0, &priv->flags))
+				enable_irq(dev_info->irq);
+		} else {
+			if (!test_and_set_bit(0, &priv->flags))
+				disable_irq(dev_info->irq);
+		}
+	}
+
+	spin_unlock_irqrestore(&priv->lock, flags);
+
+	return 0;
+}
+
+static int uio_ubicom32ring_probe(struct platform_device *pdev)
+{
+	struct uio_info *uioinfo;
+	struct uio_mem *uiomem;
+	struct uio_ubicom32ring_data *priv;
+	struct uio_ubicom32ring_regs *regs;
+	struct resource *mem_resource;
+	struct resource *irqtx_resource;
+	struct resource *irqrx_resource;
+	int ret = -EINVAL;
+	int i;
+
+	uioinfo = kzalloc(sizeof(struct uio_info), GFP_KERNEL);
+	if (!uioinfo) {
+		dev_err(&pdev->dev, "unable to kmalloc\n");
+		return -ENOMEM;
+	}
+
+	/*
+	 * Allocate private data with some string space after
+	 */
+	i = sizeof(DRIVER_NAME) + 1;
+	i += pdev->dev.platform_data ? strlen(pdev->dev.platform_data) : 0;
+	priv = kzalloc(sizeof(struct uio_ubicom32ring_data) + i, GFP_KERNEL);
+	if (!priv) {
+		dev_err(&pdev->dev, "unable to kmalloc\n");
+		kfree(uioinfo);
+		return -ENOMEM;
+	}
+
+	strcpy(priv->name, DRIVER_NAME ":");
+	if (pdev->dev.platform_data) {
+		strcat(priv->name, pdev->dev.platform_data);
+	}
+	uioinfo->priv = priv;
+	uioinfo->name = priv->name;
+	uioinfo->version = "0.1";
+
+	priv->uioinfo = uioinfo;
+	spin_lock_init(&priv->lock);
+	priv->flags = 0; /* interrupt is enabled to begin with */
+
+	/*
+	 * Get our resources, the IRQ_TX and IRQ_RX are optional.
+	 */
+	priv->irq_tx = 0xFF;
+	irqtx_resource = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+	if (irqtx_resource) {
+		priv->irq_tx = irqtx_resource->start;
+	}
+
+	uioinfo->irq = -1;
+	priv->irq_rx = 0xFF;
+	irqrx_resource = platform_get_resource(pdev, IORESOURCE_IRQ, 1);
+	if (irqrx_resource) {
+		priv->irq_rx = irqrx_resource->start;
+		uioinfo->irq = priv->irq_rx;
+		uioinfo->handler = uio_ubicom32ring_handler;
+	}
+
+	mem_resource = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!mem_resource || !mem_resource->start) {
+		dev_err(&pdev->dev, "No valid memory resource found\n");
+		ret = -ENODEV;
+		goto fail;
+	}
+	regs = (struct uio_ubicom32ring_regs *)mem_resource->start;
+	priv->regs = regs;
+
+	if (regs->version != UIO_UBICOM32RING_REG_VERSION) {
+		dev_err(&pdev->dev, "version %d not supported\n", regs->version);
+		ret = -ENODEV;
+		goto fail;
+	}
+
+	/*
+	 * First range is the shared register space, if we have any
+	 */
+	uiomem = &uioinfo->mem[0];
+	if (regs->regs_size) {
+		uiomem->memtype = UIO_MEM_PHYS;
+		uiomem->addr = (u32_t)regs->regs;
+		uiomem->size = regs->regs_size;
+		++uiomem;
+		dev_info(&pdev->dev, "regs:%p (%u) / rings: %d found\n", regs->regs, regs->regs_size, regs->num_rings);
+	} else {
+		dev_info(&pdev->dev, "rings: %d found\n", regs->num_rings);
+	}
+
+	/*
+	 * The rest of the range correspond to the rings
+	 */
+	for (i = 0; i < regs->num_rings; i++) {
+		dev_info(&pdev->dev, "\t%d: entries:%d ring:%p\n",
+			 i, regs->rings[i]->entries, &(regs->rings[i]->ring));
+		if (uiomem >= &uioinfo->mem[MAX_UIO_MAPS]) {
+			dev_warn(&pdev->dev, "device has more than "
+					__stringify(MAX_UIO_MAPS)
+					" I/O memory resources.\n");
+			break;
+		}
+
+		uiomem->memtype = UIO_MEM_PHYS;
+		uiomem->addr = (u32_t)&(regs->rings[i]->head);
+		uiomem->size = (regs->rings[i]->entries * sizeof(u32_t)) +
+				sizeof(struct uio_ubicom32ring_desc);
+		++uiomem;
+	}
+
+	while (uiomem < &uioinfo->mem[MAX_UIO_MAPS]) {
+		uiomem->size = 0;
+		++uiomem;
+	}
+
+	/* This driver requires no hardware specific kernel code to handle
+	 * interrupts. Instead, the interrupt handler simply disables the
+	 * interrupt in the interrupt controller. User space is responsible
+	 * for performing hardware specific acknowledge and re-enabling of
+	 * the interrupt in the interrupt controller.
+	 *
+	 * Interrupt sharing is not supported.
+	 */
+	uioinfo->irq_flags = IRQF_DISABLED;
+	uioinfo->irqcontrol = uio_ubicom32ring_irqcontrol;
+
+	ret = uio_register_device(&pdev->dev, priv->uioinfo);
+	if (ret) {
+		dev_err(&pdev->dev, "unable to register uio device\n");
+		goto fail;
+	}
+
+	platform_set_drvdata(pdev, priv);
+
+	dev_info(&pdev->dev, "'%s' using irq: rx %d tx %d, regs %p\n",
+		 priv->name, priv->irq_rx, priv->irq_tx, priv->regs);
+
+	return 0;
+
+fail:
+	kfree(uioinfo);
+	kfree(priv);
+	return ret;
+}
+
+static int uio_ubicom32ring_remove(struct platform_device *pdev)
+{
+	struct uio_ubicom32ring_data *priv = platform_get_drvdata(pdev);
+
+	uio_unregister_device(priv->uioinfo);
+	kfree(priv->uioinfo);
+	kfree(priv);
+	return 0;
+}
+
+static struct platform_driver uio_ubicom32ring = {
+	.probe = uio_ubicom32ring_probe,
+	.remove = uio_ubicom32ring_remove,
+	.driver = {
+		.name = DRIVER_NAME,
+		.owner = THIS_MODULE,
+	},
+};
+
+static int __init uio_ubicom32ring_init(void)
+{
+	return platform_driver_register(&uio_ubicom32ring);
+}
+
+static void __exit uio_ubicom32ring_exit(void)
+{
+	platform_driver_unregister(&uio_ubicom32ring);
+}
+
+module_init(uio_ubicom32ring_init);
+module_exit(uio_ubicom32ring_exit);
+
+MODULE_AUTHOR("Patrick Tjin");
+MODULE_DESCRIPTION("Userspace I/O driver for Ubicom32 ring buffers");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:" DRIVER_NAME);