[PATCH v2 8/9] bus: fsl-mc: dpio: add the DPAA2 DPIO object driver

[Stuart Yoder]

From: Roy Pledge <roy.pledge@xxxxxxx>

The DPIO driver registers with the fsl-mc bus to handle bus-related
events for DPIO objects.  Key responsibility is mapping I/O
regions, setting up interrupt handlers, and calling the DPIO
service initialization during probe.

Signed-off-by: Roy Pledge <roy.pledge@xxxxxxx>
Signed-off-by: Haiying Wang <haiying.wang@xxxxxxx>
Signed-off-by: Stuart Yoder <stuart.yoder@xxxxxxx>
Cc: Laurentiu Tudor <laurentiu.tudor@xxxxxxx>
Cc: Ioana Radulescu <ruxandra.radulescu@xxxxxxx>
---
-v2
   -handle error case where number of DPIOs > NR_CPUs

 drivers/bus/fsl-mc/dpio/Makefile      |   2 +-
 drivers/bus/fsl-mc/dpio/dpio-driver.c | 295 ++++++++++++++++++++++++++++++++++
 2 files changed, 296 insertions(+), 1 deletion(-)
 create mode 100644 drivers/bus/fsl-mc/dpio/dpio-driver.c

diff --git a/drivers/bus/fsl-mc/dpio/Makefile b/drivers/bus/fsl-mc/dpio/Makefile
index 0778da7..837d330 100644
--- a/drivers/bus/fsl-mc/dpio/Makefile
+++ b/drivers/bus/fsl-mc/dpio/Makefile
@@ -6,4 +6,4 @@ subdir-ccflags-y := -Werror
 
 obj-$(CONFIG_FSL_MC_DPIO) += fsl-mc-dpio.o
 
-fsl-mc-dpio-objs := dpio.o qbman-portal.o dpio-service.o
+fsl-mc-dpio-objs := dpio.o qbman-portal.o dpio-service.o dpio-driver.o
diff --git a/drivers/bus/fsl-mc/dpio/dpio-driver.c b/drivers/bus/fsl-mc/dpio/dpio-driver.c
new file mode 100644
index 0000000..76261d2
--- /dev/null
+++ b/drivers/bus/fsl-mc/dpio/dpio-driver.c
@@ -0,0 +1,295 @@
+/*
+ * Copyright 2014-2016 Freescale Semiconductor Inc.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *     * Redistributions of source code must retain the above copyright
+ *	 notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *	 notice, this list of conditions and the following disclaimer in the
+ *	 documentation and/or other materials provided with the distribution.
+ *     * Neither the name of Freescale Semiconductor nor the
+ *	 names of its contributors may be used to endorse or promote products
+ *	 derived from this software without specific prior written permission.
+ *
+ * ALTERNATIVELY, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL") as published by the Free Software
+ * Foundation, either version 2 of that License or (at your option) any
+ * later version.
+ *
+ * THIS SOFTWARE IS PROVIDED BY Freescale Semiconductor ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL Freescale Semiconductor BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <linux/types.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/interrupt.h>
+#include <linux/msi.h>
+#include <linux/dma-mapping.h>
+#include <linux/delay.h>
+
+#include <linux/fsl/mc.h>
+#include <linux/fsl/dpaa2-io.h>
+
+#include "qbman-portal.h"
+#include "dpio.h"
+#include "dpio-cmd.h"
+
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_AUTHOR("Freescale Semiconductor, Inc");
+MODULE_DESCRIPTION("DPIO Driver");
+
+struct dpio_priv {
+	struct dpaa2_io *io;
+};
+
+static irqreturn_t dpio_irq_handler(int irq_num, void *arg)
+{
+	struct device *dev = (struct device *)arg;
+	struct dpio_priv *priv = dev_get_drvdata(dev);
+
+	return dpaa2_io_irq(priv->io);
+}
+
+static void unregister_dpio_irq_handlers(struct fsl_mc_device *dpio_dev)
+{
+	struct fsl_mc_device_irq *irq;
+
+	irq = dpio_dev->irqs[0];
+
+	/* clear the affinity hint */
+	irq_set_affinity_hint(irq->msi_desc->irq, NULL);
+}
+
+static int register_dpio_irq_handlers(struct fsl_mc_device *dpio_dev, int cpu)
+{
+	struct dpio_priv *priv;
+	int error;
+	struct fsl_mc_device_irq *irq;
+	cpumask_t mask;
+
+	priv = dev_get_drvdata(&dpio_dev->dev);
+
+	irq = dpio_dev->irqs[0];
+	error = devm_request_irq(&dpio_dev->dev,
+				 irq->msi_desc->irq,
+				 dpio_irq_handler,
+				 0,
+				 dev_name(&dpio_dev->dev),
+				 &dpio_dev->dev);
+	if (error < 0) {
+		dev_err(&dpio_dev->dev,
+			"devm_request_irq() failed: %d\n",
+			error);
+		return error;
+	}
+
+	/* set the affinity hint */
+	cpumask_clear(&mask);
+	cpumask_set_cpu(cpu, &mask);
+	if (irq_set_affinity_hint(irq->msi_desc->irq, &mask))
+		dev_err(&dpio_dev->dev,
+		       "irq_set_affinity failed irq %d cpu %d\n",
+		       irq->msi_desc->irq, cpu);
+
+	return 0;
+}
+
+static int dpaa2_dpio_probe(struct fsl_mc_device *dpio_dev)
+{
+	struct dpio_attr dpio_attrs;
+	struct dpaa2_io_desc desc;
+	struct dpio_priv *priv;
+	int err = -ENOMEM;
+	struct device *dev = &dpio_dev->dev;
+	static int next_cpu = -1;
+
+	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		goto err_priv_alloc;
+
+	dev_set_drvdata(dev, priv);
+
+	err = fsl_mc_portal_allocate(dpio_dev, 0, &dpio_dev->mc_io);
+	if (err) {
+		dev_dbg(dev, "MC portal allocation failed\n");
+		err = -EPROBE_DEFER;
+		goto err_mcportal;
+	}
+
+	err = dpio_open(dpio_dev->mc_io, 0, dpio_dev->obj_desc.id,
+			&dpio_dev->mc_handle);
+	if (err) {
+		dev_err(dev, "dpio_open() failed\n");
+		goto err_open;
+	}
+
+	err = dpio_get_attributes(dpio_dev->mc_io, 0, dpio_dev->mc_handle,
+				  &dpio_attrs);
+	if (err) {
+		dev_err(dev, "dpio_get_attributes() failed %d\n", err);
+		goto err_get_attr;
+	}
+	desc.qman_version = dpio_attrs.qbman_version;
+
+	err = dpio_enable(dpio_dev->mc_io, 0, dpio_dev->mc_handle);
+	if (err) {
+		dev_err(dev, "dpio_enable() failed %d\n", err);
+		goto err_get_attr;
+	}
+
+	/* initialize DPIO descriptor */
+	desc.receives_notifications = dpio_attrs.num_priorities ? 1 : 0;
+	desc.has_8prio = dpio_attrs.num_priorities == 8 ? 1 : 0;
+	desc.dpio_id = dpio_dev->obj_desc.id;
+
+	/* get the cpu to use for the affinity hint */
+	if (next_cpu == -1)
+		next_cpu = cpumask_first(cpu_online_mask);
+	else
+		next_cpu = cpumask_next(next_cpu, cpu_online_mask);
+
+	if (!cpu_possible(next_cpu)) {
+		dev_err(dev, "probe failed. Number of DPIOs exceeds NR_CPUS.\n");
+		err = -ERANGE;
+		goto err_allocate_irqs;
+	}
+	desc.cpu = next_cpu;
+
+	/*
+	 * Set the CENA regs to be the cache inhibited area of the portal to
+	 * avoid coherency issues if a user migrates to another core.
+	 */
+	desc.regs_cena = ioremap_wc(dpio_dev->regions[1].start,
+		resource_size(&dpio_dev->regions[1]));
+	desc.regs_cinh = ioremap(dpio_dev->regions[1].start,
+		resource_size(&dpio_dev->regions[1]));
+
+	err = fsl_mc_allocate_irqs(dpio_dev);
+	if (err) {
+		dev_err(dev, "fsl_mc_allocate_irqs failed. err=%d\n", err);
+		goto err_allocate_irqs;
+	}
+
+	err = register_dpio_irq_handlers(dpio_dev, desc.cpu);
+	if (err)
+		goto err_register_dpio_irq;
+
+	priv->io = dpaa2_io_create(&desc);
+	if (!priv->io) {
+		dev_err(dev, "dpaa2_io_create failed\n");
+		goto err_dpaa2_io_create;
+	}
+
+	dev_info(dev, "probed\n");
+	dev_dbg(dev, "   receives_notifications = %d\n",
+		 desc.receives_notifications);
+	dpio_close(dpio_dev->mc_io, 0, dpio_dev->mc_handle);
+	fsl_mc_portal_free(dpio_dev->mc_io);
+
+	return 0;
+
+err_dpaa2_io_create:
+	unregister_dpio_irq_handlers(dpio_dev);
+err_register_dpio_irq:
+	fsl_mc_free_irqs(dpio_dev);
+err_allocate_irqs:
+	dpio_disable(dpio_dev->mc_io, 0, dpio_dev->mc_handle);
+err_get_attr:
+	dpio_close(dpio_dev->mc_io, 0, dpio_dev->mc_handle);
+err_open:
+	fsl_mc_portal_free(dpio_dev->mc_io);
+err_mcportal:
+	dev_set_drvdata(dev, NULL);
+err_priv_alloc:
+	return err;
+}
+
+/* Tear down interrupts for a given DPIO object */
+static void dpio_teardown_irqs(struct fsl_mc_device *dpio_dev)
+{
+	unregister_dpio_irq_handlers(dpio_dev);
+	fsl_mc_free_irqs(dpio_dev);
+}
+
+static int dpaa2_dpio_remove(struct fsl_mc_device *dpio_dev)
+{
+	struct device *dev;
+	struct dpio_priv *priv;
+	int err;
+
+	dev = &dpio_dev->dev;
+	priv = dev_get_drvdata(dev);
+
+	dpaa2_io_down(priv->io);
+
+	dpio_teardown_irqs(dpio_dev);
+
+	err = fsl_mc_portal_allocate(dpio_dev, 0, &dpio_dev->mc_io);
+	if (err) {
+		dev_err(dev, "MC portal allocation failed\n");
+		goto err_mcportal;
+	}
+
+	err = dpio_open(dpio_dev->mc_io, 0, dpio_dev->obj_desc.id,
+			&dpio_dev->mc_handle);
+	if (err) {
+		dev_err(dev, "dpio_open() failed\n");
+		goto err_open;
+	}
+
+	dpio_disable(dpio_dev->mc_io, 0, dpio_dev->mc_handle);
+
+	dpio_close(dpio_dev->mc_io, 0, dpio_dev->mc_handle);
+
+	fsl_mc_portal_free(dpio_dev->mc_io);
+
+	dev_set_drvdata(dev, NULL);
+
+	return 0;
+
+err_open:
+	fsl_mc_portal_free(dpio_dev->mc_io);
+err_mcportal:
+	return err;
+}
+
+static const struct fsl_mc_device_id dpaa2_dpio_match_id_table[] = {
+	{
+		.vendor = FSL_MC_VENDOR_FREESCALE,
+		.obj_type = "dpio",
+	},
+	{ .vendor = 0x0 }
+};
+
+static struct fsl_mc_driver dpaa2_dpio_driver = {
+	.driver = {
+		.name		= KBUILD_MODNAME,
+		.owner		= THIS_MODULE,
+	},
+	.probe		= dpaa2_dpio_probe,
+	.remove		= dpaa2_dpio_remove,
+	.match_id_table = dpaa2_dpio_match_id_table
+};
+
+static int dpio_driver_init(void)
+{
+	return fsl_mc_driver_register(&dpaa2_dpio_driver);
+}
+
+static void dpio_driver_exit(void)
+{
+	fsl_mc_driver_unregister(&dpaa2_dpio_driver);
+}
+module_init(dpio_driver_init);
+module_exit(dpio_driver_exit);
-- 
1.9.0