[PATCH v2 11/11] coresight-etm4x: Controls pertaining to the VM ID functions
Mathieu Poirier
mathieu.poirier at linaro.org
Wed Apr 29 10:16:35 PDT 2015
From: Pratik Patel <pratikp at codeaurora.org>
Adding sysfs entries to access and configure specifics about the
virtual machine ID comparator functions.
Signed-off-by: Pratik Patel <pratikp at codeaurora.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier at linaro.org>
---
.../ABI/testing/sysfs-bus-coresight-devices-etm4x | 20 +++
drivers/hwtracing/coresight/coresight-etm4x.c | 178 +++++++++++++++++++++
2 files changed, 198 insertions(+)
diff --git a/Documentation/ABI/testing/sysfs-bus-coresight-devices-etm4x b/Documentation/ABI/testing/sysfs-bus-coresight-devices-etm4x
index 8b32cb7b9723..eb5153891919 100644
--- a/Documentation/ABI/testing/sysfs-bus-coresight-devices-etm4x
+++ b/Documentation/ABI/testing/sysfs-bus-coresight-devices-etm4x
@@ -273,3 +273,23 @@ KernelVersion: 4.01
Contact: Mathieu Poirier <mathieu.poirier at linaro.org>
Description: (RW) Mask for all 8 context ID comparator value
registers (if implemented).
+
+What: /sys/bus/coresight/devices/<memory_map>.etm/vmid_idx
+Date: April 2015
+KernelVersion: 4.01
+Contact: Mathieu Poirier <mathieu.poirier at linaro.org>
+Description: (RW) Select which virtual machine ID comparator to work with.
+
+What: /sys/bus/coresight/devices/<memory_map>.etm/vmid_val
+Date: April 2015
+KernelVersion: 4.01
+Contact: Mathieu Poirier <mathieu.poirier at linaro.org>
+Description: (RW) Get/Set the virtual machine ID comparator value to
+ trigger on.
+
+What: /sys/bus/coresight/devices/<memory_map>.etm/vmid_masks
+Date: April 2015
+KernelVersion: 4.01
+Contact: Mathieu Poirier <mathieu.poirier at linaro.org>
+Description: (RW) Mask for all 8 virtual machine ID comparator value
+ registers (if implemented).
diff --git a/drivers/hwtracing/coresight/coresight-etm4x.c b/drivers/hwtracing/coresight/coresight-etm4x.c
index 58ae33980b12..cdcfa019a82c 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x.c
+++ b/drivers/hwtracing/coresight/coresight-etm4x.c
@@ -1964,6 +1964,181 @@ static ssize_t ctxid_masks_store(struct device *dev,
}
static DEVICE_ATTR_RW(ctxid_masks);
+static ssize_t vmid_idx_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ unsigned long val;
+ struct etmv4_drvdata *drvdata = dev_get_drvdata(dev->parent);
+
+ val = drvdata->vmid_idx;
+ return scnprintf(buf, PAGE_SIZE, "%#lx\n", val);
+}
+
+static ssize_t vmid_idx_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t size)
+{
+ unsigned long val;
+ struct etmv4_drvdata *drvdata = dev_get_drvdata(dev->parent);
+
+ if (kstrtoul(buf, 16, &val))
+ return -EINVAL;
+ if (val >= drvdata->numvmidc)
+ return -EINVAL;
+
+ /*
+ * Use spinlock to ensure index doesn't change while it gets
+ * dereferenced multiple times within a spinlock block elsewhere.
+ */
+ spin_lock(&drvdata->spinlock);
+ drvdata->vmid_idx = val;
+ spin_unlock(&drvdata->spinlock);
+ return size;
+}
+static DEVICE_ATTR_RW(vmid_idx);
+
+static ssize_t vmid_val_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ unsigned long val;
+ struct etmv4_drvdata *drvdata = dev_get_drvdata(dev->parent);
+
+ val = (unsigned long)drvdata->vmid_val[drvdata->vmid_idx];
+ return scnprintf(buf, PAGE_SIZE, "%#lx\n", val);
+}
+
+static ssize_t vmid_val_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t size)
+{
+ unsigned long val;
+ struct etmv4_drvdata *drvdata = dev_get_drvdata(dev->parent);
+
+ /*
+ * only implemented when vmid tracing is enabled, i.e. at least one
+ * vmid comparator is implemented and at least 8 bit vmid size
+ */
+ if (!drvdata->vmid_size || !drvdata->numvmidc)
+ return -EINVAL;
+ if (kstrtoul(buf, 16, &val))
+ return -EINVAL;
+
+ spin_lock(&drvdata->spinlock);
+ drvdata->vmid_val[drvdata->vmid_idx] = (u64)val;
+ spin_unlock(&drvdata->spinlock);
+ return size;
+}
+static DEVICE_ATTR_RW(vmid_val);
+
+static ssize_t vmid_masks_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ unsigned long val1, val2;
+ struct etmv4_drvdata *drvdata = dev_get_drvdata(dev->parent);
+
+ spin_lock(&drvdata->spinlock);
+ val1 = drvdata->vmid_mask0;
+ val2 = drvdata->vmid_mask1;
+ spin_unlock(&drvdata->spinlock);
+ return scnprintf(buf, PAGE_SIZE, "%#lx %#lx\n", val1, val2);
+}
+
+static ssize_t vmid_masks_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t size)
+{
+ u8 i, j, maskbyte;
+ unsigned long val1, val2, mask;
+ struct etmv4_drvdata *drvdata = dev_get_drvdata(dev->parent);
+ /*
+ * only implemented when vmid tracing is enabled, i.e. at least one
+ * vmid comparator is implemented and at least 8 bit vmid size
+ */
+ if (!drvdata->vmid_size || !drvdata->numvmidc)
+ return -EINVAL;
+ if (sscanf(buf, "%lx %lx", &val1, &val2) != 2)
+ return -EINVAL;
+
+ spin_lock(&drvdata->spinlock);
+
+ /*
+ * each byte[0..3] controls mask value applied to vmid
+ * comparator[0..3]
+ */
+ switch (drvdata->numvmidc) {
+ case 0x1:
+ /* COMP0, bits[7:0] */
+ drvdata->vmid_mask0 = val1 & 0xFF;
+ break;
+ case 0x2:
+ /* COMP1, bits[15:8] */
+ drvdata->vmid_mask0 = val1 & 0xFFFF;
+ break;
+ case 0x3:
+ /* COMP2, bits[23:16] */
+ drvdata->vmid_mask0 = val1 & 0xFFFFFF;
+ break;
+ case 0x4:
+ /* COMP3, bits[31:24] */
+ drvdata->vmid_mask0 = val1;
+ break;
+ case 0x5:
+ /* COMP4, bits[7:0] */
+ drvdata->vmid_mask0 = val1;
+ drvdata->vmid_mask1 = val2 & 0xFF;
+ break;
+ case 0x6:
+ /* COMP5, bits[15:8] */
+ drvdata->vmid_mask0 = val1;
+ drvdata->vmid_mask1 = val2 & 0xFFFF;
+ break;
+ case 0x7:
+ /* COMP6, bits[23:16] */
+ drvdata->vmid_mask0 = val1;
+ drvdata->vmid_mask1 = val2 & 0xFFFFFF;
+ break;
+ case 0x8:
+ /* COMP7, bits[31:24] */
+ drvdata->vmid_mask0 = val1;
+ drvdata->vmid_mask1 = val2;
+ break;
+ default:
+ break;
+ }
+
+ /*
+ * If software sets a mask bit to 1, it must program relevant byte
+ * of vmid comparator value 0x0, otherwise behavior is unpredictable.
+ * For example, if bit[3] of vmid_mask0 is 1, we must clear bits[31:24]
+ * of vmid comparator0 value (corresponding to byte 0) register.
+ */
+ mask = drvdata->vmid_mask0;
+ for (i = 0; i < drvdata->numvmidc; i++) {
+ /* mask value of corresponding vmid comparator */
+ maskbyte = mask & ETMv4_EVENT_MASK;
+ /*
+ * each bit corresponds to a byte of respective vmid comparator
+ * value register
+ */
+ for (j = 0; j < 8; j++) {
+ if (maskbyte & 1)
+ drvdata->vmid_val[i] &= ~(0xFF << (j * 8));
+ maskbyte >>= 1;
+ }
+ /* Select the next vmid comparator mask value */
+ if (i == 3)
+ /* vmid comparators[4-7] */
+ mask = drvdata->vmid_mask1;
+ else
+ mask >>= 0x8;
+ }
+ spin_unlock(&drvdata->spinlock);
+ return size;
+}
+static DEVICE_ATTR_RW(vmid_masks);
+
static ssize_t status_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
@@ -2149,6 +2324,9 @@ static struct attribute *coresight_etmv4_attrs[] = {
&dev_attr_ctxid_idx.attr,
&dev_attr_ctxid_val.attr,
&dev_attr_ctxid_masks.attr,
+ &dev_attr_vmid_idx.attr,
+ &dev_attr_vmid_val.attr,
+ &dev_attr_vmid_masks.attr,
&dev_attr_status.attr,
&dev_attr_mgmt.attr,
&dev_attr_trcidr.attr,
--
1.9.1
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