Hi Tingwei,
On 11/14/20 5:36 AM, Tingwei Zhang wrote:
Hi Anshuman,
On Tue, Nov 10, 2020 at 08:45:04PM +0800, Anshuman Khandual wrote:
From: Suzuki K Poulose suzuki.poulose@arm.com
Add ETE as one of the supported device types we support with ETM4x driver. The devices are named following the existing convention as ete<N>.
ETE mandates that the trace resource status register is programmed before the tracing is turned on. For the moment simply write to it indicating TraceActive.
Signed-off-by: Suzuki K Poulose suzuki.poulose@arm.com Signed-off-by: Anshuman Khandual anshuman.khandual@arm.com
@@ -1742,6 +1758,19 @@ static int etm4_probe(struct device *dev, void __iomem *base) if (!desc.access.io_mem || fwnode_property_present(dev_fwnode(dev), "qcom,skip-power-up")) drvdata->skip_power_up = true;
- major = ETM_ARCH_MAJOR_VERSION(drvdata->arch);
- minor = ETM_ARCH_MINOR_VERSION(drvdata->arch);
- if (drvdata->arch >= ETM_ARCH_ETE) {
type_name = "ete";major -= 4;- } else {
type_name = "etm";- }
When trace unit supports ETE, could it be still compatible with ETMv4.4? Can use selectively use it as ETM instead of ETE?
No. Even though most of the register sets are compatible, there are additional restrictions and some new rules for the ETE. So, when you treat the ETE as an ETMv4.4, you could be treading into "UNPREDICTABLE" behaviors.
Suzuki