intel_th: pti: Support Low Power Path output port type

The Low Power Path (LPP) output port type, looks mostly like PTI to
the software, with a few additional bits in the control register.

This extends the PTI driver to support LPP ports as well.

Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>

diff --git a/drivers/hwtracing/intel_th/pti.c b/drivers/hwtracing/intel_th/pti.c
index 35738b5..e96a1fc 100644 (file)
--- a/drivers/hwtracing/intel_th/pti.c
+++ b/drivers/hwtracing/intel_th/pti.c
@@ -1,7 +1,7 @@
 /*
  * Intel(R) Trace Hub PTI output driver
  *
- * Copyright (C) 2014-2015 Intel Corporation.
+ * Copyright (C) 2014-2016 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,
@@ -34,6 +34,8 @@ struct pti_device {
        unsigned int            freeclk;
        unsigned int            clkdiv;
        unsigned int            patgen;
+       unsigned int            lpp_dest_mask;
+       unsigned int            lpp_dest;
 };
 
 /* map PTI widths to MODE settings of PTI_CTL register */
@@ -163,6 +165,7 @@ static int intel_th_pti_activate(struct intel_th_device *thdev)
                ctl |= PTI_FCEN;
        ctl |= pti->mode << __ffs(PTI_MODE);
        ctl |= pti->clkdiv << __ffs(PTI_CLKDIV);
+       ctl |= pti->lpp_dest << __ffs(LPP_DEST);
 
        iowrite32(ctl, pti->base + REG_PTI_CTL);
 
@@ -192,6 +195,15 @@ static void read_hw_config(struct pti_device *pti)
                pti->mode = pti_width_mode(4);
        if (!pti->clkdiv)
                pti->clkdiv = 1;
+
+       if (pti->thdev->output.type == GTH_LPP) {
+               if (ctl & LPP_PTIPRESENT)
+                       pti->lpp_dest_mask |= LPP_DEST_PTI;
+               if (ctl & LPP_BSSBPRESENT)
+                       pti->lpp_dest_mask |= LPP_DEST_EXI;
+               if (ctl & LPP_DEST)
+                       pti->lpp_dest = 1;
+       }
 }
 
 static int intel_th_pti_probe(struct intel_th_device *thdev)
@@ -239,10 +251,103 @@ static struct intel_th_driver intel_th_pti_driver = {
        },
 };
 
-module_driver(intel_th_pti_driver,
-             intel_th_driver_register,
-             intel_th_driver_unregister);
+static const char * const lpp_dest_str[] = { "pti", "exi" };
+
+static ssize_t lpp_dest_show(struct device *dev, struct device_attribute *attr,
+                            char *buf)
+{
+       struct pti_device *pti = dev_get_drvdata(dev);
+       ssize_t ret = 0;
+       int i;
+
+       for (i = ARRAY_SIZE(lpp_dest_str) - 1; i >= 0; i--) {
+               const char *fmt = pti->lpp_dest == i ? "[%s] " : "%s ";
+
+               if (!(pti->lpp_dest_mask & BIT(i)))
+                       continue;
+
+               ret += scnprintf(buf + ret, PAGE_SIZE - ret,
+                                fmt, lpp_dest_str[i]);
+       }
+
+       if (ret)
+               buf[ret - 1] = '\n';
+
+       return ret;
+}
+
+static ssize_t lpp_dest_store(struct device *dev, struct device_attribute *attr,
+                             const char *buf, size_t size)
+{
+       struct pti_device *pti = dev_get_drvdata(dev);
+       ssize_t ret = -EINVAL;
+       int i;
+
+       for (i = 0; i < ARRAY_SIZE(lpp_dest_str); i++)
+               if (sysfs_streq(buf, lpp_dest_str[i]))
+                       break;
+
+       if (i < ARRAY_SIZE(lpp_dest_str) && pti->lpp_dest_mask & BIT(i)) {
+               pti->lpp_dest = i;
+               ret = size;
+       }
+
+       return ret;
+}
+
+static DEVICE_ATTR_RW(lpp_dest);
+
+static struct attribute *lpp_output_attrs[] = {
+       &dev_attr_mode.attr,
+       &dev_attr_freerunning_clock.attr,
+       &dev_attr_clock_divider.attr,
+       &dev_attr_lpp_dest.attr,
+       NULL,
+};
+
+static struct attribute_group lpp_output_group = {
+       .attrs  = lpp_output_attrs,
+};
+
+static struct intel_th_driver intel_th_lpp_driver = {
+       .probe          = intel_th_pti_probe,
+       .remove         = intel_th_pti_remove,
+       .activate       = intel_th_pti_activate,
+       .deactivate     = intel_th_pti_deactivate,
+       .attr_group     = &lpp_output_group,
+       .driver = {
+               .name   = "lpp",
+               .owner  = THIS_MODULE,
+       },
+};
+
+static int __init intel_th_pti_lpp_init(void)
+{
+       int err;
+
+       err = intel_th_driver_register(&intel_th_pti_driver);
+       if (err)
+               return err;
+
+       err = intel_th_driver_register(&intel_th_lpp_driver);
+       if (err) {
+               intel_th_driver_unregister(&intel_th_pti_driver);
+               return err;
+       }
+
+       return 0;
+}
+
+module_init(intel_th_pti_lpp_init);
+
+static void __exit intel_th_pti_lpp_exit(void)
+{
+       intel_th_driver_unregister(&intel_th_pti_driver);
+       intel_th_driver_unregister(&intel_th_lpp_driver);
+}
+
+module_exit(intel_th_pti_lpp_exit);
 
 MODULE_LICENSE("GPL v2");
-MODULE_DESCRIPTION("Intel(R) Trace Hub PTI output driver");
+MODULE_DESCRIPTION("Intel(R) Trace Hub PTI/LPP output driver");
 MODULE_AUTHOR("Alexander Shishkin <alexander.shishkin@linux.intel.com>");

diff --git a/drivers/hwtracing/intel_th/pti.h b/drivers/hwtracing/intel_th/pti.h
index 20883f5..30827be 100644 (file)
--- a/drivers/hwtracing/intel_th/pti.h
+++ b/drivers/hwtracing/intel_th/pti.h
@@ -23,7 +23,15 @@ enum {
 #define PTI_EN         BIT(0)
 #define PTI_FCEN       BIT(1)
 #define PTI_MODE       0xf0
+#define LPP_PTIPRESENT BIT(8)
+#define LPP_BSSBPRESENT        BIT(9)
 #define PTI_CLKDIV     0x000f0000
 #define PTI_PATGENMODE 0x00f00000
+#define LPP_DEST       BIT(25)
+#define LPP_BSSBACT    BIT(30)
+#define LPP_LPPBUSY    BIT(31)
+
+#define LPP_DEST_PTI   BIT(0)
+#define LPP_DEST_EXI   BIT(1)
 
 #endif /* __INTEL_TH_STH_H__ */