From 4a584be1d0061f7992a661f7c1a20c8688a50a19 Mon Sep 17 00:00:00 2001 From: Pratik Patel Date: Wed, 13 May 2015 10:34:18 -0600 Subject: coresight-etm4x: Controls pertaining to the context ID functions Adding sysfs entries to access and configure specifics about the context ID comparator functions. Signed-off-by: Pratik Patel Signed-off-by: Mathieu Poirier Signed-off-by: Greg Kroah-Hartman diff --git a/Documentation/ABI/testing/sysfs-bus-coresight-devices-etm4x b/Documentation/ABI/testing/sysfs-bus-coresight-devices-etm4x index 5c7391d..f251b2c 100644 --- a/Documentation/ABI/testing/sysfs-bus-coresight-devices-etm4x +++ b/Documentation/ABI/testing/sysfs-bus-coresight-devices-etm4x @@ -242,3 +242,22 @@ Date: April 2015 KernelVersion: 4.01 Contact: Mathieu Poirier Description: (RW) Controls the selection of the resources in the trace unit. + +What: /sys/bus/coresight/devices/.etm/ctxid_idx +Date: April 2015 +KernelVersion: 4.01 +Contact: Mathieu Poirier +Description: (RW) Select which context ID comparator to work with. + +What: /sys/bus/coresight/devices/.etm/ctxid_val +Date: April 2015 +KernelVersion: 4.01 +Contact: Mathieu Poirier +Description: (RW) Get/Set the context ID comparator value to trigger on. + +What: /sys/bus/coresight/devices/.etm/ctxid_masks +Date: April 2015 +KernelVersion: 4.01 +Contact: Mathieu Poirier +Description: (RW) Mask for all 8 context ID comparator value + registers (if implemented). diff --git a/drivers/hwtracing/coresight/coresight-etm4x.c b/drivers/hwtracing/coresight/coresight-etm4x.c index 308a48d..e94784f 100644 --- a/drivers/hwtracing/coresight/coresight-etm4x.c +++ b/drivers/hwtracing/coresight/coresight-etm4x.c @@ -1780,6 +1780,190 @@ static ssize_t res_ctrl_store(struct device *dev, } static DEVICE_ATTR_RW(res_ctrl); +static ssize_t ctxid_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->ctxid_idx; + return scnprintf(buf, PAGE_SIZE, "%#lx\n", val); +} + +static ssize_t ctxid_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->numcidc) + 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->ctxid_idx = val; + spin_unlock(&drvdata->spinlock); + return size; +} +static DEVICE_ATTR_RW(ctxid_idx); + +static ssize_t ctxid_val_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + u8 idx; + unsigned long val; + struct etmv4_drvdata *drvdata = dev_get_drvdata(dev->parent); + + spin_lock(&drvdata->spinlock); + idx = drvdata->ctxid_idx; + val = (unsigned long)drvdata->ctxid_val[idx]; + spin_unlock(&drvdata->spinlock); + return scnprintf(buf, PAGE_SIZE, "%#lx\n", val); +} + +static ssize_t ctxid_val_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t size) +{ + u8 idx; + unsigned long val; + struct etmv4_drvdata *drvdata = dev_get_drvdata(dev->parent); + + /* + * only implemented when ctxid tracing is enabled, i.e. at least one + * ctxid comparator is implemented and ctxid is greater than 0 bits + * in length + */ + if (!drvdata->ctxid_size || !drvdata->numcidc) + return -EINVAL; + if (kstrtoul(buf, 16, &val)) + return -EINVAL; + + spin_lock(&drvdata->spinlock); + idx = drvdata->ctxid_idx; + drvdata->ctxid_val[idx] = (u64)val; + spin_unlock(&drvdata->spinlock); + return size; +} +static DEVICE_ATTR_RW(ctxid_val); + +static ssize_t ctxid_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->ctxid_mask0; + val2 = drvdata->ctxid_mask1; + spin_unlock(&drvdata->spinlock); + return scnprintf(buf, PAGE_SIZE, "%#lx %#lx\n", val1, val2); +} + +static ssize_t ctxid_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 ctxid tracing is enabled, i.e. at least one + * ctxid comparator is implemented and ctxid is greater than 0 bits + * in length + */ + if (!drvdata->ctxid_size || !drvdata->numcidc) + 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 ctxid + * comparator[0..3] + */ + switch (drvdata->numcidc) { + case 0x1: + /* COMP0, bits[7:0] */ + drvdata->ctxid_mask0 = val1 & 0xFF; + break; + case 0x2: + /* COMP1, bits[15:8] */ + drvdata->ctxid_mask0 = val1 & 0xFFFF; + break; + case 0x3: + /* COMP2, bits[23:16] */ + drvdata->ctxid_mask0 = val1 & 0xFFFFFF; + break; + case 0x4: + /* COMP3, bits[31:24] */ + drvdata->ctxid_mask0 = val1; + break; + case 0x5: + /* COMP4, bits[7:0] */ + drvdata->ctxid_mask0 = val1; + drvdata->ctxid_mask1 = val2 & 0xFF; + break; + case 0x6: + /* COMP5, bits[15:8] */ + drvdata->ctxid_mask0 = val1; + drvdata->ctxid_mask1 = val2 & 0xFFFF; + break; + case 0x7: + /* COMP6, bits[23:16] */ + drvdata->ctxid_mask0 = val1; + drvdata->ctxid_mask1 = val2 & 0xFFFFFF; + break; + case 0x8: + /* COMP7, bits[31:24] */ + drvdata->ctxid_mask0 = val1; + drvdata->ctxid_mask1 = val2; + break; + default: + break; + } + /* + * If software sets a mask bit to 1, it must program relevant byte + * of ctxid comparator value 0x0, otherwise behavior is unpredictable. + * For example, if bit[3] of ctxid_mask0 is 1, we must clear bits[31:24] + * of ctxid comparator0 value (corresponding to byte 0) register. + */ + mask = drvdata->ctxid_mask0; + for (i = 0; i < drvdata->numcidc; i++) { + /* mask value of corresponding ctxid comparator */ + maskbyte = mask & ETMv4_EVENT_MASK; + /* + * each bit corresponds to a byte of respective ctxid comparator + * value register + */ + for (j = 0; j < 8; j++) { + if (maskbyte & 1) + drvdata->ctxid_val[i] &= ~(0xFF << (j * 8)); + maskbyte >>= 1; + } + /* Select the next ctxid comparator mask value */ + if (i == 3) + /* ctxid comparators[4-7] */ + mask = drvdata->ctxid_mask1; + else + mask >>= 0x8; + } + + spin_unlock(&drvdata->spinlock); + return size; +} +static DEVICE_ATTR_RW(ctxid_masks); + static ssize_t cpu_show(struct device *dev, struct device_attribute *attr, char *buf) { @@ -1832,6 +2016,9 @@ static struct attribute *coresight_etmv4_attrs[] = { &dev_attr_cntr_ctrl.attr, &dev_attr_res_idx.attr, &dev_attr_res_ctrl.attr, + &dev_attr_ctxid_idx.attr, + &dev_attr_ctxid_val.attr, + &dev_attr_ctxid_masks.attr, &dev_attr_cpu.attr, NULL, }; -- cgit v0.10.2