linux-toradex.git/drivers/hwtracing/intel_th/Kconfig, branch master

intel_th: avoid using deprecated page->mapping, index fields

2025-04-15T11:29:03+00:00

The struct page->mapping, index fields are deprecated and soon to be only
available as part of a folio.

It is likely the intel_th code which sets page->mapping, index is was
implemented out of concern that some aspect of the page fault logic may
encounter unexpected problems should they not.

However, the appropriate interface for inserting kernel-allocated memory is
vm_insert_page() in a VM_MIXEDMAP. By using the helper function
vmf_insert_mixed() we can do this with minimal churn in the existing fault
handler.

By doing so, we bypass the remainder of the faulting logic. The pages are
still pinned so there is no possibility of anything unexpected being done
with the pages once established.

It would also be reasonable to pre-map everything on fault, however to
minimise churn we retain the fault handler.

We also eliminate all code which clears page->mapping on teardown as this
has now become unnecessary.

The MSU code relies on faulting to function correctly, so is by definition
dependent on CONFIG_MMU. We avoid spurious reports about compilation
failure for unsupported platforms by making this requirement explicit in
Kconfig as part of this change too.

Signed-off-by: Lorenzo Stoakes 
Acked-by: Alexander Shishkin 
Link: https://lore.kernel.org/r/20250331125608.60300-1-lorenzo.stoakes@oracle.com
Signed-off-by: Greg Kroah-Hartman

treewide: Add SPDX license identifier - Makefile/Kconfig

2019-05-21T08:50:46+00:00

Add SPDX license identifiers to all Make/Kconfig files which:

 - Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner 
Signed-off-by: Greg Kroah-Hartman

intel_th: Add ACPI glue layer

2018-03-28T15:47:23+00:00

The Trace Hub devices now can be enumerated as ACPI devices, which
translates into "Host Debugger mode". There are two IDs: one for
PCH Trace Hub, and one for the uncore Trace Hub. These are expected
to stay the same across all platforms.

Signed-off-by: Alexander Shishkin

intel_th: Depend on HAS_IOMEM

2016-02-20T22:09:14+00:00

This driver requires io memory to operate, so don't even consider it
for NO_IOMEM architectures.

Reported-by: Richard Weinberger 
Signed-off-by: Alexander Shishkin 
Signed-off-by: Greg Kroah-Hartman

intel_th: INTEL_TH should depend on HAS_DMA

2016-02-08T06:43:17+00:00

If NO_DMA=y:

    ERROR: "dma_free_coherent" [drivers/hwtracing/intel_th/intel_th_msu.ko] undefined!
    ERROR: "dma_alloc_coherent" [drivers/hwtracing/intel_th/intel_th_msu.ko] undefined!
    ERROR: "dma_supported" [drivers/hwtracing/intel_th/intel_th.ko] undefined!

Add a dependency on HAS_DMA to fix this.

Signed-off-by: Geert Uytterhoeven 
Signed-off-by: Alexander Shishkin 
Signed-off-by: Greg Kroah-Hartman

intel_th: Add PTI output driver

2015-10-04T19:28:58+00:00

Parallel Trace Interface (PTI) unit is a trace output device that sends
data over a PTI port.

The driver provides interfaces to configure bus width, bus clock divider
and mode. Tracing is enabled via output device's "active" attribute.

Signed-off-by: Alexander Shishkin 
Signed-off-by: Greg Kroah-Hartman

intel_th: Add Memory Storage Unit driver

2015-10-04T19:28:58+00:00

Memory Storage Unit (MSU) is a trace output device that collects trace
data to system memory. It consists of 2 independent Memory Storage
Controllers (MSCs).

This driver provides userspace interfaces to configure in-memory tracing
parameters, such as contiguous (high-order allocation) buffer or multiblock
(scatter list) buffer mode, wrapping (data overwrite) and number and sizes
of windows in multiblock mode. Userspace can read the buffers via mmap()ing
or read()ing of the corresponding device node.

Signed-off-by: Laurent Fert 
Signed-off-by: Alexander Shishkin 
Signed-off-by: Greg Kroah-Hartman

intel_th: Add Software Trace Hub driver

2015-10-04T19:28:58+00:00

Software Trace Hub (STH) is a trace source device in the Intel TH
architecture, it generates data that then goes through the switch into
one or several output ports.

STH collects data from software sources using the stm device class
abstraction.

Signed-off-by: Alexander Shishkin 
Signed-off-by: Greg Kroah-Hartman

intel_th: Add Global Trace Hub driver

2015-10-04T19:28:58+00:00

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 
Signed-off-by: Alexander Shishkin 
Signed-off-by: Greg Kroah-Hartman

intel_th: Add pci glue layer for Intel(R) Trace Hub

2015-10-04T19:28:58+00:00

This patch adds basic support for PCI-based Intel TH devices. It requests
2 bars (configuration registers for the subdevices and STH channel MMIO
region) and calls into Intel TH core code to create the bus with subdevices
etc.

Signed-off-by: Alexander Shishkin 
Signed-off-by: Greg Kroah-Hartman