These changes are the raw update to linux-4.4.6-rt14. Kernel sources

[kvmfornfv.git] / kernel / drivers / hwtracing / coresight / coresight-etb10.c

diff --git a/kernel/drivers/hwtracing/coresight/coresight-etb10.c b/kernel/drivers/hwtracing/coresight/coresight-etb10.c
index 4004986..77d0f9c 100644 (file)
--- a/kernel/drivers/hwtracing/coresight/coresight-etb10.c
+++ b/kernel/drivers/hwtracing/coresight/coresight-etb10.c
@@ -22,10 +22,11 @@
 #include <linux/uaccess.h>
 #include <linux/slab.h>
 #include <linux/spinlock.h>
-#include <linux/clk.h>
+#include <linux/pm_runtime.h>
 #include <linux/seq_file.h>
 #include <linux/coresight.h>
 #include <linux/amba/bus.h>
+#include <linux/clk.h>
 
 #include "coresight-priv.h"
 
@@ -66,9 +67,9 @@
  * struct etb_drvdata - specifics associated to an ETB component
  * @base:      memory mapped base address for this component.
  * @dev:       the device entity associated to this component.
+ * @atclk:     optional clock for the core parts of the ETB.
  * @csdev:     component vitals needed by the framework.
  * @miscdev:   specifics to handle "/dev/xyz.etb" entry.
- * @clk:       the clock this component is associated to.
  * @spinlock:  only one at a time pls.
  * @in_use:    synchronise user space access to etb buffer.
  * @buf:       area of memory where ETB buffer content gets sent.
@@ -79,9 +80,9 @@
 struct etb_drvdata {
        void __iomem            *base;
        struct device           *dev;
+       struct clk              *atclk;
        struct coresight_device *csdev;
        struct miscdevice       miscdev;
-       struct clk              *clk;
        spinlock_t              spinlock;
        atomic_t                in_use;
        u8                      *buf;
@@ -92,17 +93,14 @@ struct etb_drvdata {
 
 static unsigned int etb_get_buffer_depth(struct etb_drvdata *drvdata)
 {
-       int ret;
        u32 depth = 0;
 
-       ret = clk_prepare_enable(drvdata->clk);
-       if (ret)
-               return ret;
+       pm_runtime_get_sync(drvdata->dev);
 
        /* RO registers don't need locking */
        depth = readl_relaxed(drvdata->base + ETB_RAM_DEPTH_REG);
 
-       clk_disable_unprepare(drvdata->clk);
+       pm_runtime_put(drvdata->dev);
        return depth;
 }
 
@@ -137,12 +135,9 @@ static void etb_enable_hw(struct etb_drvdata *drvdata)
 static int etb_enable(struct coresight_device *csdev)
 {
        struct etb_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
-       int ret;
        unsigned long flags;
 
-       ret = clk_prepare_enable(drvdata->clk);
-       if (ret)
-               return ret;
+       pm_runtime_get_sync(drvdata->dev);
 
        spin_lock_irqsave(&drvdata->spinlock, flags);
        etb_enable_hw(drvdata);
@@ -252,7 +247,7 @@ static void etb_disable(struct coresight_device *csdev)
        drvdata->enable = false;
        spin_unlock_irqrestore(&drvdata->spinlock, flags);
 
-       clk_disable_unprepare(drvdata->clk);
+       pm_runtime_put(drvdata->dev);
 
        dev_info(drvdata->dev, "ETB disabled\n");
 }
@@ -339,16 +334,12 @@ static const struct file_operations etb_fops = {
 static ssize_t status_show(struct device *dev,
                           struct device_attribute *attr, char *buf)
 {
-       int ret;
        unsigned long flags;
        u32 etb_rdr, etb_sr, etb_rrp, etb_rwp;
        u32 etb_trg, etb_cr, etb_ffsr, etb_ffcr;
        struct etb_drvdata *drvdata = dev_get_drvdata(dev->parent);
 
-       ret = clk_prepare_enable(drvdata->clk);
-       if (ret)
-               goto out;
-
+       pm_runtime_get_sync(drvdata->dev);
        spin_lock_irqsave(&drvdata->spinlock, flags);
        CS_UNLOCK(drvdata->base);
 
@@ -364,7 +355,7 @@ static ssize_t status_show(struct device *dev,
        CS_LOCK(drvdata->base);
        spin_unlock_irqrestore(&drvdata->spinlock, flags);
 
-       clk_disable_unprepare(drvdata->clk);
+       pm_runtime_put(drvdata->dev);
 
        return sprintf(buf,
                       "Depth:\t\t0x%x\n"
@@ -377,7 +368,7 @@ static ssize_t status_show(struct device *dev,
                       "Flush ctrl:\t0x%x\n",
                       etb_rdr, etb_sr, etb_rrp, etb_rwp,
                       etb_trg, etb_cr, etb_ffsr, etb_ffcr);
-out:
+
        return -EINVAL;
 }
 static DEVICE_ATTR_RO(status);
@@ -438,6 +429,12 @@ static int etb_probe(struct amba_device *adev, const struct amba_id *id)
                return -ENOMEM;
 
        drvdata->dev = &adev->dev;
+       drvdata->atclk = devm_clk_get(&adev->dev, "atclk"); /* optional */
+       if (!IS_ERR(drvdata->atclk)) {
+               ret = clk_prepare_enable(drvdata->atclk);
+               if (ret)
+                       return ret;
+       }
        dev_set_drvdata(dev, drvdata);
 
        /* validity for the resource is already checked by the AMBA core */
@@ -449,21 +446,19 @@ static int etb_probe(struct amba_device *adev, const struct amba_id *id)
 
        spin_lock_init(&drvdata->spinlock);
 
-       drvdata->clk = adev->pclk;
-       ret = clk_prepare_enable(drvdata->clk);
-       if (ret)
-               return ret;
-
        drvdata->buffer_depth = etb_get_buffer_depth(drvdata);
-       clk_disable_unprepare(drvdata->clk);
+       pm_runtime_put(&adev->dev);
 
-       if (drvdata->buffer_depth < 0)
+       if (drvdata->buffer_depth & 0x80000000)
                return -EINVAL;
 
        drvdata->buf = devm_kzalloc(dev,
                                    drvdata->buffer_depth * 4, GFP_KERNEL);
-       if (!drvdata->buf)
+       if (!drvdata->buf) {
+               dev_err(dev, "Failed to allocate %u bytes for buffer data\n",
+                       drvdata->buffer_depth * 4);
                return -ENOMEM;
+       }
 
        desc = devm_kzalloc(dev, sizeof(*desc), GFP_KERNEL);
        if (!desc)
@@ -503,6 +498,32 @@ static int etb_remove(struct amba_device *adev)
        return 0;
 }
 
+#ifdef CONFIG_PM
+static int etb_runtime_suspend(struct device *dev)
+{
+       struct etb_drvdata *drvdata = dev_get_drvdata(dev);
+
+       if (drvdata && !IS_ERR(drvdata->atclk))
+               clk_disable_unprepare(drvdata->atclk);
+
+       return 0;
+}
+
+static int etb_runtime_resume(struct device *dev)
+{
+       struct etb_drvdata *drvdata = dev_get_drvdata(dev);
+
+       if (drvdata && !IS_ERR(drvdata->atclk))
+               clk_prepare_enable(drvdata->atclk);
+
+       return 0;
+}
+#endif
+
+static const struct dev_pm_ops etb_dev_pm_ops = {
+       SET_RUNTIME_PM_OPS(etb_runtime_suspend, etb_runtime_resume, NULL)
+};
+
 static struct amba_id etb_ids[] = {
        {
                .id     = 0x0003b907,
@@ -515,6 +536,8 @@ static struct amba_driver etb_driver = {
        .drv = {
                .name   = "coresight-etb10",
                .owner  = THIS_MODULE,
+               .pm     = &etb_dev_pm_ops,
+
        },
        .probe          = etb_probe,
        .remove         = etb_remove,