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path: root/drivers/hwtracing/intel_th/gth.c
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2016-11-18intel_th: gth: Handle host mode correctlyAlexander Shishkin
When detecting host debugger mode either though a module option or via the scratchpad register, do not export any configuration or capture related attributes to userspace and refuse attempts by the output drivers to configure output ports. This way, GTH can still act as a hub and ensure that the other components that rely on its presence continue to function properly, namely the source devices. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
2016-07-01intel_th: gth: Fix a source commentAlexander Shishkin
There's a kerneldoc comment that'd been derived from another one by way of copying-and-pasting but hadn't been subsequently amended to reflect the purpose of the function. Fix this. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
2016-07-01intel_th: Add runtime power management handlingAlexander Shishkin
Currently, an Intel TH (pci) device will be always active, because the devices on the 'intel_th' bus don't implement runtime pm to track their usage. To address this, this patch adds runtime pm support to the 'intel_th' bus and some additional bits for the hub. The 'output' type device is in use while a capture is active; the 'source' type device (STH) relies on its child stm class device for runtime pm tracking. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
2016-02-20intel_th: Update scratchpad bits according to enabled output activityAlexander Shishkin
Intel TH implements a scratchpad register to indicate to the firmware and external debuggers what trace configuration is enabled so that everybody plays nicely together. The register is a bit field and the bit assignment convention is described in the developer's manual. This patch enables the driver to automatically set scratchpad register bits according to the output configuration that's enabled. Based on work by Yann Fouassier. Signed-off-by: Yann Fouassier <yann.fouassier@intel.com> Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-20intel_th: gth: Remove commented-out codeAlexander Shishkin
There's a commented-out function in the GTH driver that's a leftover from previous versions of the driver, where we tried to inherit the pre-existing configuration, which didn't prove to be a sound idea. This patch removes the function. No functional changes. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-16intel_th: Check for NULL instead of ERR_PTRDan Carpenter
devm_ioremap() returns NULL on error, it doesn't return an ERR_PTR, which is what the current code does. This patch corrects these checks. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-10-04intel_th: Add Global Trace Hub driverAlexander Shishkin
Global Trace Hub (GTH) is the central component of Intel TH architecture; it carries out switching between the trace sources and trace outputs, can enable/disable tracing, perform STP encoding, internal buffering, control backpressure from outputs to sources and so on. This property is also reflected in the software model; GTH (switch) driver is required for the other subdevices to probe, because it matches trace output devices against its output ports and configures them accordingly. It also implements an interface for output ports to request trace enabling or disabling and a few other useful things. For userspace, it provides an attribute group "masters", which allows configuration of per-master trace output destinations for up to master 255 and "256+" meaning "masters 256 and above". It also provides an attribute group to discover and configure some of the parameters of its output ports, called "outputs". Via these the user can set up data retention policy for an individual output port or check if it is in reset state. Signed-off-by: Laurent Fert <laurent.fert@intel.com> Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>