--- /dev/null
+/*
+ * Intel(R) Trace Hub PTI output driver
+ *
+ * Copyright (C) 2014-2015 Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/types.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/sizes.h>
+#include <linux/printk.h>
+#include <linux/slab.h>
+#include <linux/mm.h>
+#include <linux/io.h>
+
+#include "intel_th.h"
+#include "pti.h"
+
+struct pti_device {
+ void __iomem *base;
+ struct intel_th_device *thdev;
+ unsigned int mode;
+ unsigned int freeclk;
+ unsigned int clkdiv;
+ unsigned int patgen;
+};
+
+/* map PTI widths to MODE settings of PTI_CTL register */
+static const unsigned int pti_mode[] = {
+ 0, 4, 8, 0, 12, 0, 0, 0, 16, 0, 0, 0, 0, 0, 0, 0,
+};
+
+static int pti_width_mode(unsigned int width)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(pti_mode); i++)
+ if (pti_mode[i] == width)
+ return i;
+
+ return -EINVAL;
+}
+
+static ssize_t mode_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct pti_device *pti = dev_get_drvdata(dev);
+
+ return scnprintf(buf, PAGE_SIZE, "%d\n", pti_mode[pti->mode]);
+}
+
+static ssize_t mode_store(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t size)
+{
+ struct pti_device *pti = dev_get_drvdata(dev);
+ unsigned long val;
+ int ret;
+
+ ret = kstrtoul(buf, 10, &val);
+ if (ret)
+ return ret;
+
+ ret = pti_width_mode(val);
+ if (ret < 0)
+ return ret;
+
+ pti->mode = ret;
+
+ return size;
+}
+
+static DEVICE_ATTR_RW(mode);
+
+static ssize_t
+freerunning_clock_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct pti_device *pti = dev_get_drvdata(dev);
+
+ return scnprintf(buf, PAGE_SIZE, "%d\n", pti->freeclk);
+}
+
+static ssize_t
+freerunning_clock_store(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t size)
+{
+ struct pti_device *pti = dev_get_drvdata(dev);
+ unsigned long val;
+ int ret;
+
+ ret = kstrtoul(buf, 10, &val);
+ if (ret)
+ return ret;
+
+ pti->freeclk = !!val;
+
+ return size;
+}
+
+static DEVICE_ATTR_RW(freerunning_clock);
+
+static ssize_t
+clock_divider_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct pti_device *pti = dev_get_drvdata(dev);
+
+ return scnprintf(buf, PAGE_SIZE, "%d\n", 1u << pti->clkdiv);
+}
+
+static ssize_t
+clock_divider_store(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t size)
+{
+ struct pti_device *pti = dev_get_drvdata(dev);
+ unsigned long val;
+ int ret;
+
+ ret = kstrtoul(buf, 10, &val);
+ if (ret)
+ return ret;
+
+ if (!is_power_of_2(val) || val > 8 || !val)
+ return -EINVAL;
+
+ pti->clkdiv = val;
+
+ return size;
+}
+
+static DEVICE_ATTR_RW(clock_divider);
+
+static struct attribute *pti_output_attrs[] = {
+ &dev_attr_mode.attr,
+ &dev_attr_freerunning_clock.attr,
+ &dev_attr_clock_divider.attr,
+ NULL,
+};
+
+static struct attribute_group pti_output_group = {
+ .attrs = pti_output_attrs,
+};
+
+static int intel_th_pti_activate(struct intel_th_device *thdev)
+{
+ struct pti_device *pti = dev_get_drvdata(&thdev->dev);
+ u32 ctl = PTI_EN;
+
+ if (pti->patgen)
+ ctl |= pti->patgen << __ffs(PTI_PATGENMODE);
+ if (pti->freeclk)
+ ctl |= PTI_FCEN;
+ ctl |= pti->mode << __ffs(PTI_MODE);
+ ctl |= pti->clkdiv << __ffs(PTI_CLKDIV);
+
+ iowrite32(ctl, pti->base + REG_PTI_CTL);
+
+ intel_th_trace_enable(thdev);
+
+ return 0;
+}
+
+static void intel_th_pti_deactivate(struct intel_th_device *thdev)
+{
+ struct pti_device *pti = dev_get_drvdata(&thdev->dev);
+
+ intel_th_trace_disable(thdev);
+
+ iowrite32(0, pti->base + REG_PTI_CTL);
+}
+
+static void read_hw_config(struct pti_device *pti)
+{
+ u32 ctl = ioread32(pti->base + REG_PTI_CTL);
+
+ pti->mode = (ctl & PTI_MODE) >> __ffs(PTI_MODE);
+ pti->clkdiv = (ctl & PTI_CLKDIV) >> __ffs(PTI_CLKDIV);
+ pti->freeclk = !!(ctl & PTI_FCEN);
+
+ if (!pti_mode[pti->mode])
+ pti->mode = pti_width_mode(4);
+ if (!pti->clkdiv)
+ pti->clkdiv = 1;
+}
+
+static int intel_th_pti_probe(struct intel_th_device *thdev)
+{
+ struct device *dev = &thdev->dev;
+ struct resource *res;
+ struct pti_device *pti;
+ void __iomem *base;
+ int ret;
+
+ res = intel_th_device_get_resource(thdev, IORESOURCE_MEM, 0);
+ if (!res)
+ return -ENODEV;
+
+ base = devm_ioremap(dev, res->start, resource_size(res));
+ if (!base)
+ return -ENOMEM;
+
+ pti = devm_kzalloc(dev, sizeof(*pti), GFP_KERNEL);
+ if (!pti)
+ return -ENOMEM;
+
+ pti->thdev = thdev;
+ pti->base = base;
+
+ read_hw_config(pti);
+
+ ret = sysfs_create_group(&dev->kobj, &pti_output_group);
+ if (ret)
+ return ret;
+
+ dev_set_drvdata(dev, pti);
+
+ return 0;
+}
+
+static void intel_th_pti_remove(struct intel_th_device *thdev)
+{
+}
+
+static struct intel_th_driver intel_th_pti_driver = {
+ .probe = intel_th_pti_probe,
+ .remove = intel_th_pti_remove,
+ .activate = intel_th_pti_activate,
+ .deactivate = intel_th_pti_deactivate,
+ .driver = {
+ .name = "pti",
+ .owner = THIS_MODULE,
+ },
+};
+
+module_driver(intel_th_pti_driver,
+ intel_th_driver_register,
+ intel_th_driver_unregister);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("Intel(R) Trace Hub PTI output driver");
+MODULE_AUTHOR("Alexander Shishkin <alexander.shishkin@linux.intel.com>");
Code Review / kvmfornfv.git / blobdiff