From c34cc23f1dcb77c66b5cd074f83dee61bfcbe567 Mon Sep 17 00:00:00 2001 From: Suzuki K Poulose Date: Wed, 11 Jul 2018 13:40:24 -0600 Subject: coresight: tmc: Add configuration support for trace buffer size Now that we can dynamically switch between contiguous memory and SG table depending on the trace buffer size, provide the support for selecting an appropriate buffer size. Cc: Mathieu Poirier Signed-off-by: Suzuki K Poulose Acked-by: Rob Herring Signed-off-by: Mathieu Poirier Signed-off-by: Greg Kroah-Hartman --- drivers/hwtracing/coresight/coresight-tmc.c | 33 +++++++++++++++++++++++++++++ 1 file changed, 33 insertions(+) (limited to 'drivers/hwtracing') diff --git a/drivers/hwtracing/coresight/coresight-tmc.c b/drivers/hwtracing/coresight/coresight-tmc.c index bc8fc860c473..1b817ec1192c 100644 --- a/drivers/hwtracing/coresight/coresight-tmc.c +++ b/drivers/hwtracing/coresight/coresight-tmc.c @@ -277,8 +277,41 @@ static ssize_t trigger_cntr_store(struct device *dev, } static DEVICE_ATTR_RW(trigger_cntr); +static ssize_t buffer_size_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct tmc_drvdata *drvdata = dev_get_drvdata(dev->parent); + + return sprintf(buf, "%#x\n", drvdata->size); +} + +static ssize_t buffer_size_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t size) +{ + int ret; + unsigned long val; + struct tmc_drvdata *drvdata = dev_get_drvdata(dev->parent); + + /* Only permitted for TMC-ETRs */ + if (drvdata->config_type != TMC_CONFIG_TYPE_ETR) + return -EPERM; + + ret = kstrtoul(buf, 0, &val); + if (ret) + return ret; + /* The buffer size should be page aligned */ + if (val & (PAGE_SIZE - 1)) + return -EINVAL; + drvdata->size = val; + return size; +} + +static DEVICE_ATTR_RW(buffer_size); + static struct attribute *coresight_tmc_attrs[] = { &dev_attr_trigger_cntr.attr, + &dev_attr_buffer_size.attr, NULL, }; -- cgit v1.2.3