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authorDapeng Mi <dapeng1.mi@linux.intel.com>2026-09-17 09:52:33 +0800
committerIngo Molnar <mingo@kernel.org>2026-09-22 11:37:46 +0200
commit0102c8c7fdfc4bd700971daff2b94470f4eafae4 (patch)
tree531306c2299f9a269f0a986e29f17ba972180104 /Documentation/ABI/testing/sysfs-auxdisplay-linedisp
downloadlinux-stable-0102c8c7fdfc4bd700971daff2b94470f4eafae4.tar.gz
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perf/x86/intel: Rename DMR offcore_rsp attribute to offmodule_rspgrafted
DMR introduces Offmodule Response events in place of the legacy Offcore Response events, but it still exposes the inherited offcore_rsp PMU attribute for programming the corresponding MSR data. Rename the DMR PMU attribute to offmodule_rsp so the sysfs interface matches the underlying event name and avoids user & tooling confusion. Signed-off-by: Dapeng Mi <dapeng1.mi@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Link: https://patch.msgid.link/20260917015234.981153-12-dapeng1.mi@linux.intel.com
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+What: /sys/.../message
+Date: October 2021
+KernelVersion: 5.16
+Description:
+ Controls the text message displayed on character line displays.
+
+ Reading returns the current message with a trailing newline.
+ Writing updates the displayed message. Messages longer than the
+ display width will automatically scroll. Trailing newlines in
+ input are automatically trimmed.
+
+ Writing an empty string clears the display.
+
+ Example:
+ echo "Hello World" > message
+ cat message # Returns "Hello World\n"
+
+What: /sys/.../num_chars
+Date: November 2025
+KernelVersion: 6.18
+Contact: Jean-François Lessard <jefflessard3@gmail.com>
+Description:
+ Read-only attribute showing the character width capacity of
+ the line display device. Messages longer than this will scroll.
+
+ Example:
+ cat num_chars # Returns "16\n" for 16-char display
+
+What: /sys/.../scroll_step_ms
+Date: October 2021
+KernelVersion: 5.16
+Description:
+ Controls the scrolling speed for messages longer than the display
+ width, specified in milliseconds per scroll step.
+
+ Setting to 0 disables scrolling. Default is 500ms.
+
+ Example:
+ echo "250" > scroll_step_ms # 4Hz scrolling
+ cat scroll_step_ms # Returns "250\n"
+
+What: /sys/.../map_seg7
+Date: January 2024
+KernelVersion: 6.9
+Description:
+ Read/write binary blob representing the ASCII-to-7-segment
+ display conversion table used by the linedisp driver, as defined
+ by struct seg7_conversion_map in <linux/map_to_7segment.h>.
+
+ Only visible on displays with 7-segment capability.
+
+ This attribute is not human-readable. Writes must match the
+ struct size exactly, else -EINVAL is returned; reads return the
+ entire mapping as a binary blob.
+
+ This interface and its implementation match existing conventions
+ used in segment-mapped display drivers since 2005.
+
+ ABI note: This style of binary sysfs attribute *is an exception*
+ to current "one value per file, text only" sysfs rules, for
+ historical compatibility and driver uniformity. New drivers are
+ discouraged from introducing additional binary sysfs ABIs.
+
+ Reference interface guidance:
+ - include/uapi/linux/map_to_7segment.h
+
+What: /sys/.../map_seg14
+Date: January 2024
+KernelVersion: 6.9
+Description:
+ Read/write binary blob representing the ASCII-to-14-segment
+ display conversion table used by the linedisp driver, as defined
+ by struct seg14_conversion_map in <linux/map_to_14segment.h>.
+
+ Only visible on displays with 14-segment capability.
+
+ This attribute is not human-readable. Writes must match the
+ struct size exactly, else -EINVAL is returned; reads return the
+ entire mapping as a binary blob.
+
+ This interface and its implementation match existing conventions
+ used by segment-mapped display drivers since 2005.
+
+ ABI note: This style of binary sysfs attribute *is an exception*
+ to current "one value per file, text only" sysfs rules, for
+ historical compatibility and driver uniformity. New drivers are
+ discouraged from introducing additional binary sysfs ABIs.
+
+ Reference interface guidance:
+ - include/uapi/linux/map_to_14segment.h