* Re: [PATCH v6 05/12] PCI: liveupdate: Keep bus numbers constant during Live Update
From: Pasha Tatashin @ 2026-06-14 14:01 UTC (permalink / raw)
To: Pranjal Shrivastava
Cc: David Matlack, kexec, linux-doc, linux-kernel, linux-mm,
linux-pci, Adithya Jayachandran, Alexander Graf, Alex Williamson,
Bjorn Helgaas, Chris Li, David Rientjes, Jacob Pan,
Jason Gunthorpe, Jonathan Corbet, Josh Hilke, Leon Romanovsky,
Lukas Wunner, Mike Rapoport, Parav Pandit, Pasha Tatashin,
Pratyush Yadav, Saeed Mahameed, Samiullah Khawaja, Shuah Khan,
Vipin Sharma, William Tu, Yi Liu
In-Reply-To: <aiQAJRINEKiwCmVm@google.com>
On 2026-06-06 11:10:29+00:00, Pranjal Shrivastava wrote:
> On Fri, May 22, 2026 at 08:24:03PM +0000, David Matlack wrote:
>
> > During a Live Update, preserved devices must be allowed to continue
> > performing memory transactions so the kernel cannot change the fabric
> > topology, including bus numbers, since that would require disabling
> > and flushing any memory transactions first.
> >
> > To keep bus numbers constant, always inherit the secondary and
> > subordinate bus numbers assigned to bridges during scanning, instead of
> > assigning new ones, if any PCI devices are being preserved. Note that
> > the kernel inherits bus numbers even on bridges without any downstream
> > endpoints that were preserved. This avoids accidentally assigning a
> > bridge a new window that overlaps with a preserved device that is
> > downstream of a different bridge.
> >
> > If a bridge is scanned with a broken topology or has no bus numbers
> > set during a Live Update, refuse to assign it new bus numbers and refuse
> > to enumerate devices below it until the Live Update is finished. This is
> > a safety measure to prevent topology conflicts.
> >
> > Require that CONFIG_CARDBUS is not enabled to enable
> > CONFIG_PCI_LIVEUPDATE since inheriting bus numbers on PCI-to-CardBus
> > bridges requires additional work but is not a priority at the moment.
> >
> > Signed-off-by: David Matlack <dmatlack@google.com>
> > ---
> > .../admin-guide/kernel-parameters.txt | 6 +-
> > drivers/pci/Kconfig | 2 +-
> > drivers/pci/liveupdate.c | 83 ++++++++++++++++++-
> > drivers/pci/liveupdate.h | 14 ++++
> > drivers/pci/probe.c | 17 +++-
> > include/linux/pci_liveupdate.h | 4 +
> > 6 files changed, 119 insertions(+), 7 deletions(-)
>
> [...]
>
> > + incoming = pci_liveupdate_flb_get_incoming();
> > + if (!incoming) {
> > + dev->liveupdate.inherit_buses = false;
> > + goto out;
> > + }
> > +
> > + /*
> > + * It is safe to sample incoming->ser->nr_devices and then
> > + * drop the rwsem since nr_devices will only decrease. Thus the
> > + * only "race" is that the current scan will be overly
> > + * conservative and force bus inheritance.
> > + */
> > + dev->liveupdate.inherit_buses = incoming->ser->nr_devices;
>
> Nit: inherit_buses is a bool, while compiler will handle it correctly,
> maybe we could:
>
> dev->liveupdate.inherit_buses = !!incoming->ser->nr_devices
+1
>
> OR
>
> dev->liveupdate.inherit_buses = (incoming->ser->nr_devices > 0)
>
> for readability?
>
> > + pci_liveupdate_flb_put_incoming();
> > + }
> > +
> > +out:
> > + return dev->liveupdate.inherit_buses;
> > +}
> > +
>
> [...]
>
> > /*
> > @@ -1497,8 +1501,7 @@ static int pci_scan_bridge_extend(struct pci_bus *bus, struct pci_dev *dev,
> > * do in the second pass.
> > */
> > if (!pass) {
> > - if (pcibios_assign_all_busses() || broken)
> > -
> > + if (assign_new_buses || broken)
> > /*
> > * Temporarily disable forwarding of the
> > * configuration cycles on all bridges in
> > @@ -1512,6 +1515,11 @@ static int pci_scan_bridge_extend(struct pci_bus *bus, struct pci_dev *dev,
> > goto out;
> > }
> >
> > + if (liveupdate) {
> > + pci_err(dev, "Cannot reconfigure bridge during Live Update, skipping\n");
> > + goto out;
> > + }
>
> Quite helpful! Thanks :)
>
> > +
> > /* Clear errors */
> > pci_write_config_word(dev, PCI_STATUS, 0xffff);
> >
> > @@ -1572,6 +1580,7 @@ static int pci_scan_bridge_extend(struct pci_bus *bus, struct pci_dev *dev,
> > pci_write_config_word(dev, PCI_BRIDGE_CONTROL, bctl);
> >
> > pm_runtime_put(&dev->dev);
> > + pci_liveupdate_scan_bridge_end(dev, pass);
> >
> > return max;
> > }
>
> With the minor nit above,
> Reviewed-by: Pranjal Shrivastava <praan@google.com>
>
> Thanks,
> Praan
^ permalink raw reply
* [PATCH v3 0/7] tracing/probes: Add more typecast features
From: Masami Hiramatsu (Google) @ 2026-06-14 14:53 UTC (permalink / raw)
To: Steven Rostedt, Mathieu Desnoyers
Cc: Jonathan Corbet, Shuah Khan, Masami Hiramatsu, linux-kernel,
linux-trace-kernel, linux-doc, linux-kselftest
Hi,
Here is the 3rd version of series to introduce more typecast features
to probe events. The previous version is here:
https://lore.kernel.org/all/178105268094.21760.13668249930524377840.stgit@devnote2/
In this version, I fixed various problems Sashiko reviewed and add new
test cases.
Steve introduced BTF typecast feature for eprobe[1].
This series extends it and add more options:
1. Expanding BTF typecast to kprobe and fprobe.
(currently only function entry/exit)
2. Introduce container_of like typecast. This adds a "assigned
member" option to the typecast.
(STRUCT,MEMBER)VAR->ANOTHER_MEMBER
This casts VAR to STRUCT type but the VAR is as the address
of STRUCT.MEMBER. In C, it is:
container_of(VAR, STRUCT, MEMBER)->ANOTHER_MEMBER
3. Support nested typecast, e.g.
(STRUCT)((STRUCT2)VAR->MEMBER2)->MEMBER
the nest level must be smaller than 3.
4. Add $current variable to point "current" task_struct.
This is useful with typecast, e.g.
(task_struct)$current->pid
5. per-cpu dereference support.
Intrdouce this_cpu_read(VAR) and this_cpu_ptr(VAR) to
access per-cpu data on the current CPU (accessing other CPU
data is not stable, because it can be changed.)
You can access the member of per-cpu data structure using
typecast like:
(STRUCT)this_cpu_ptr(VAR)->MEMBER
And added a test script to test part of them.
[1] https://lore.kernel.org/all/20260601130746.2139d926@gandalf.local.home/
---
Masami Hiramatsu (Google) (7):
tracing/events: Fix to check the simple_tsk_fn creation
tracing/probes: Support typecast for various probe events
tracing/probes: Support nested typecast
tracing/probes: Support field specifier option for typecast
tracing/probes: Add $current variable support
tracing/probes: Add this_cpu_read() and this_cpu_ptr() dereference method to fetcharg
tracing/probes: Add a new testcase for BTF typecasts
Documentation/trace/eprobetrace.rst | 9
Documentation/trace/fprobetrace.rst | 10
Documentation/trace/kprobetrace.rst | 11 +
kernel/trace/trace.c | 6
kernel/trace/trace_probe.c | 413 +++++++++++++++-----
kernel/trace/trace_probe.h | 19 +
kernel/trace/trace_probe_tmpl.h | 33 +-
samples/trace_events/trace-events-sample.c | 45 ++
samples/trace_events/trace-events-sample.h | 34 ++
.../ftrace/test.d/dynevent/btf_probe_event.tc | 51 ++
.../ftrace/test.d/dynevent/fprobe_syntax_errors.tc | 9
.../ftrace/test.d/kprobe/kprobe_syntax_errors.tc | 9
.../ftrace/test.d/kprobe/uprobe_syntax_errors.tc | 5
13 files changed, 540 insertions(+), 114 deletions(-)
create mode 100644 tools/testing/selftests/ftrace/test.d/dynevent/btf_probe_event.tc
--
Masami Hiramatsu (Google) <mhiramat@kernel.org>
^ permalink raw reply
* [PATCH v3 1/7] tracing/events: Fix to check the simple_tsk_fn creation
From: Masami Hiramatsu (Google) @ 2026-06-14 14:53 UTC (permalink / raw)
To: Steven Rostedt, Mathieu Desnoyers
Cc: Jonathan Corbet, Shuah Khan, Masami Hiramatsu, linux-kernel,
linux-trace-kernel, linux-doc, linux-kselftest
In-Reply-To: <178144880282.159464.16882854283219530040.stgit@devnote2>
From: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Sashiko pointed that this sample code does not correctly handle the
failure of thread creation because kthread_run() can return -errno.
Check the simple_tsk_fn is correctly initialized (created) or not.
Link: https://sashiko.dev/#/patchset/178092865666.163648.10457567771536160909.stgit%40devnote2
Fixes: 9cfe06f8cd5c ("tracing/events: add trace-events-sample")
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
---
Changes in v3:
- Recover the usage counter.
---
samples/trace_events/trace-events-sample.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/samples/trace_events/trace-events-sample.c b/samples/trace_events/trace-events-sample.c
index ecc7db237f2e..82344a78e471 100644
--- a/samples/trace_events/trace-events-sample.c
+++ b/samples/trace_events/trace-events-sample.c
@@ -107,6 +107,11 @@ int foo_bar_reg(void)
* for consistency sake, we still take the thread_mutex.
*/
simple_tsk_fn = kthread_run(simple_thread_fn, NULL, "event-sample-fn");
+ if (IS_ERR_OR_NULL(simple_tsk_fn)) {
+ pr_err("Failed to create simple_thread_fn");
+ simple_thread_cnt--;
+ simple_tsk_fn = NULL;
+ }
out:
mutex_unlock(&thread_mutex);
return 0;
^ permalink raw reply related
* [PATCH v3 2/7] tracing/probes: Support typecast for various probe events
From: Masami Hiramatsu (Google) @ 2026-06-14 14:53 UTC (permalink / raw)
To: Steven Rostedt, Mathieu Desnoyers
Cc: Jonathan Corbet, Shuah Khan, Masami Hiramatsu, linux-kernel,
linux-trace-kernel, linux-doc, linux-kselftest
In-Reply-To: <178144880282.159464.16882854283219530040.stgit@devnote2>
From: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Support BTF typecast feature on other probe events, but only if it is
kernel function entry or return, and must use function parameter name
or $retval. This means you can do:
(STRUCT)PARAM->MEMBER
but you can not do (this should be enabled by nesting support)
(STRUCT)%reg->MEMBER
To support other probe events, we just need to use last_struct type
when we find a function parameter in parse_btf_arg().
This also update <tracefs>/README file to show struct typecast.
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
---
Changes in v3:
- Clarify the limitation.
Changes in v2:
- Fix to re-enable typecast on eprobe.
---
Documentation/trace/fprobetrace.rst | 3 +++
Documentation/trace/kprobetrace.rst | 4 ++++
kernel/trace/trace.c | 2 +-
kernel/trace/trace_probe.c | 14 +++++++++-----
kernel/trace/trace_probe.h | 5 +++++
5 files changed, 22 insertions(+), 6 deletions(-)
diff --git a/Documentation/trace/fprobetrace.rst b/Documentation/trace/fprobetrace.rst
index b4c2ca3d02c1..7435ded2d66d 100644
--- a/Documentation/trace/fprobetrace.rst
+++ b/Documentation/trace/fprobetrace.rst
@@ -57,6 +57,9 @@ Synopsis of fprobe-events
(u8/u16/u32/u64/s8/s16/s32/s64), hexadecimal types
(x8/x16/x32/x64), "char", "string", "ustring", "symbol", "symstr"
and bitfield are supported.
+ (STRUCT)FIELD->MEMBER[->MEMBER] : If BTF is supported, typecast FIELD to
+ a pointer to STRUCT and then derference the pointer defined by
+ ->MEMBER.
(\*1) This is available only when BTF is enabled.
(\*2) only for the probe on function entry (offs == 0). Note, this argument access
diff --git a/Documentation/trace/kprobetrace.rst b/Documentation/trace/kprobetrace.rst
index 3b6791c17e9b..f73614997d52 100644
--- a/Documentation/trace/kprobetrace.rst
+++ b/Documentation/trace/kprobetrace.rst
@@ -61,6 +61,10 @@ Synopsis of kprobe_events
(x8/x16/x32/x64), VFS layer common type(%pd/%pD), "char",
"string", "ustring", "symbol", "symstr" and bitfield are
supported.
+ (STRUCT)FIELD->MEMBER[->MEMBER] : If BTF is supported, typecast FIELD to
+ a pointer to STRUCT and then derference the pointer defined by
+ ->MEMBER. Note that this is available only when the probe is
+ on function entry.
(\*1) only for the probe on function entry (offs == 0). Note, this argument access
is best effort, because depending on the argument type, it may be passed on
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 6eb4d3097a4d..aa93e7b01146 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -4325,7 +4325,7 @@ static const char readme_msg[] =
#ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API
"\t $stack<index>, $stack, $retval, $comm, $arg<N>,\n"
#ifdef CONFIG_PROBE_EVENTS_BTF_ARGS
- "\t <argname>[->field[->field|.field...]],\n"
+ "\t [(structname)]<argname>[->field[->field|.field...]],\n"
#endif
#else
"\t $stack<index>, $stack, $retval, $comm,\n"
diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
index fd1caa1f9723..9158f1f22a62 100644
--- a/kernel/trace/trace_probe.c
+++ b/kernel/trace/trace_probe.c
@@ -759,7 +759,10 @@ static int parse_btf_arg(char *varname,
return -ENOENT;
found:
- type = btf_type_skip_modifiers(ctx->btf, tid, &tid);
+ if (ctx->struct_btf)
+ type = ctx->last_struct;
+ else
+ type = btf_type_skip_modifiers(ctx->btf, tid, &tid);
found_type:
if (!type) {
trace_probe_log_err(ctx->offset, BAD_BTF_TID);
@@ -836,10 +839,11 @@ static int handle_typecast(char *arg, struct fetch_insn **pcode,
char *tmp;
int ret;
- /* Currently this only works for eprobes */
- if (!(ctx->flags & TPARG_FL_TEVENT)) {
- trace_probe_log_err(ctx->offset, TYPECAST_NOT_EVENT);
- return -EINVAL;
+ if (!(tparg_is_event_probe(ctx->flags) ||
+ tparg_is_function_entry(ctx->flags) ||
+ tparg_is_function_return(ctx->flags))) {
+ trace_probe_log_err(ctx->offset, NOSUP_BTFARG);
+ return -EOPNOTSUPP;
}
tmp = strchr(arg, ')');
diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h
index 15758cc11fc6..883938a74aee 100644
--- a/kernel/trace/trace_probe.h
+++ b/kernel/trace/trace_probe.h
@@ -414,6 +414,11 @@ static inline bool tparg_is_function_return(unsigned int flags)
return (flags & TPARG_FL_LOC_MASK) == (TPARG_FL_KERNEL | TPARG_FL_RETURN);
}
+static inline bool tparg_is_event_probe(unsigned int flags)
+{
+ return !!(flags & TPARG_FL_TEVENT);
+}
+
struct traceprobe_parse_context {
struct trace_event_call *event;
/* BTF related parameters */
^ permalink raw reply related
* [PATCH v3 3/7] tracing/probes: Support nested typecast
From: Masami Hiramatsu (Google) @ 2026-06-14 14:53 UTC (permalink / raw)
To: Steven Rostedt, Mathieu Desnoyers
Cc: Jonathan Corbet, Shuah Khan, Masami Hiramatsu, linux-kernel,
linux-trace-kernel, linux-doc, linux-kselftest
In-Reply-To: <178144880282.159464.16882854283219530040.stgit@devnote2>
From: Masami Hiramatsu (Google) <mhiramat@kernel.org>
When we hit an open parenthesis right after typecast closing
parenthesis, it means we have nested typecast. This allows us to
typecast a generic data member in a structure to a pointer to
another structure.
For example, to cast a DATA_MEMBER of VAR structure to STRUCT pointer
and get MEMBER value.
(STRUCT)(VAR->DATA_MEMBER)->MEMBER
Also, we can nest typecast.
(STRUCT1)((STRUCT2)$ARG->FIELD2)->FIELD1
Currently the max nest level is limited to 3.
This also allows user to use typecasting for registers or stacks on
kprobe events. e.g.
(STRUCT)(%ax)->MEMBER
(STRUCT)($stack0)->MEMBER
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
---
Changes in v2:
- Fix to skip "->" after closing parenthetsis.
---
Documentation/trace/eprobetrace.rst | 2 +
Documentation/trace/fprobetrace.rst | 2 +
Documentation/trace/kprobetrace.rst | 2 +
kernel/trace/trace.c | 1
kernel/trace/trace_probe.c | 76 ++++++++++++++++++++++++++++++++---
kernel/trace/trace_probe.h | 7 +++
6 files changed, 82 insertions(+), 8 deletions(-)
diff --git a/Documentation/trace/eprobetrace.rst b/Documentation/trace/eprobetrace.rst
index fe3602540569..cd0b4aa7f896 100644
--- a/Documentation/trace/eprobetrace.rst
+++ b/Documentation/trace/eprobetrace.rst
@@ -50,6 +50,8 @@ Synopsis of eprobe_events
a pointer to STRUCT and then derference the pointer defined by
->MEMBER. Note that when this is used, the FIELD name does not
need to be prefixed with a '$'.
+ (STRUCT)(FETCHARG)->MEMBER[->MEMBER] : typecast can nest, so the above can
+ also be used with another FETCHARG instead of FIELD.
Types
-----
diff --git a/Documentation/trace/fprobetrace.rst b/Documentation/trace/fprobetrace.rst
index 7435ded2d66d..6b8bb27bb62d 100644
--- a/Documentation/trace/fprobetrace.rst
+++ b/Documentation/trace/fprobetrace.rst
@@ -60,6 +60,8 @@ Synopsis of fprobe-events
(STRUCT)FIELD->MEMBER[->MEMBER] : If BTF is supported, typecast FIELD to
a pointer to STRUCT and then derference the pointer defined by
->MEMBER.
+ (STRUCT)(FETCHARG)->MEMBER[->MEMBER] : typecast can nest, so the above can
+ also be used with another FETCHARG instead of FIELD.
(\*1) This is available only when BTF is enabled.
(\*2) only for the probe on function entry (offs == 0). Note, this argument access
diff --git a/Documentation/trace/kprobetrace.rst b/Documentation/trace/kprobetrace.rst
index f73614997d52..c4382765d5b2 100644
--- a/Documentation/trace/kprobetrace.rst
+++ b/Documentation/trace/kprobetrace.rst
@@ -65,6 +65,8 @@ Synopsis of kprobe_events
a pointer to STRUCT and then derference the pointer defined by
->MEMBER. Note that this is available only when the probe is
on function entry.
+ (STRUCT)(FETCHARG)->MEMBER[->MEMBER] : typecast can nest, so the above can
+ also be used with another FETCHARG instead of FIELD.
(\*1) only for the probe on function entry (offs == 0). Note, this argument access
is best effort, because depending on the argument type, it may be passed on
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index aa93e7b01146..4f70318918c2 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -4326,6 +4326,7 @@ static const char readme_msg[] =
"\t $stack<index>, $stack, $retval, $comm, $arg<N>,\n"
#ifdef CONFIG_PROBE_EVENTS_BTF_ARGS
"\t [(structname)]<argname>[->field[->field|.field...]],\n"
+ "\t [(structname)](fetcharg)->field[->field|.field...],\n"
#endif
#else
"\t $stack<index>, $stack, $retval, $comm,\n"
diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
index 9158f1f22a62..dba73aaa8ade 100644
--- a/kernel/trace/trace_probe.c
+++ b/kernel/trace/trace_probe.c
@@ -832,10 +832,35 @@ static int query_btf_struct(const char *sname, struct traceprobe_parse_context *
return 0;
}
+/* Find the matching closing parenthesis for a given opening parenthesis. */
+static char *find_matched_close_paren(char *s)
+{
+ char *p = s;
+ int count = 0;
+
+ while (*p) {
+ if (*p == '(')
+ count++;
+ else if (*p == ')') {
+ if (--count == 0)
+ return p;
+ }
+ p++;
+ }
+ return NULL;
+}
+
+static int
+parse_probe_arg(char *arg, const struct fetch_type *type,
+ struct fetch_insn **pcode, struct fetch_insn *end,
+ struct traceprobe_parse_context *ctx);
+
static int handle_typecast(char *arg, struct fetch_insn **pcode,
struct fetch_insn *end,
struct traceprobe_parse_context *ctx)
{
+ int orig_offset = ctx->offset;
+ bool nested = false;
char *tmp;
int ret;
@@ -852,19 +877,56 @@ static int handle_typecast(char *arg, struct fetch_insn **pcode,
DEREF_OPEN_BRACE);
return -EINVAL;
}
- *tmp = '\0';
- ret = query_btf_struct(arg + 1, ctx);
- *tmp = ')';
+ *tmp++ = '\0';
+
+ /* Handle the nested structure like (STRUCT)(VAR->FIELD)->... */
+ if (*tmp == '(') {
+ char *close = find_matched_close_paren(tmp);
+
+ ctx->offset += tmp - arg;
+ if (!close) {
+ trace_probe_log_err(ctx->offset, DEREF_OPEN_BRACE);
+ return -EINVAL;
+ }
+ /* We expect a field access for typecast */
+ if (close[1] != '-' || close[2] != '>') {
+ trace_probe_log_err(ctx->offset + close - tmp + 1,
+ TYPECAST_REQ_FIELD);
+ return -EINVAL;
+ }
+ ctx->nested_level++;
+ if (ctx->nested_level > TRACEPROBE_MAX_NESTED_LEVEL) {
+ trace_probe_log_err(ctx->offset, TOO_MANY_NESTED);
+ return -E2BIG;
+ }
+ *close = '\0';
+
+ ctx->offset += 1; /* for the '(' */
+ /* We need to parse the nested one */
+ ret = parse_probe_arg(tmp + 1, find_fetch_type(NULL, ctx->flags),
+ pcode, end, ctx);
+ if (ret < 0)
+ return ret;
+ ctx->nested_level--;
+ clear_struct_btf(ctx);
+
+ tmp = close + 3;/* Skip "->" after closing parenthesis */
+ nested = true;
+ }
+
+ ret = query_btf_struct(arg + 1, ctx);
if (ret < 0) {
trace_probe_log_err(ctx->offset + 1, NO_PTR_STRCT);
return -EINVAL;
}
- tmp++;
-
- ctx->offset += tmp - arg;
- ret = parse_btf_arg(tmp, pcode, end, ctx);
+ ctx->offset = orig_offset + tmp - arg;
+ /* If it is nested, tmp points to the field name. */
+ if (nested)
+ ret = parse_btf_field(tmp, ctx->last_struct, pcode, end, ctx);
+ else
+ ret = parse_btf_arg(tmp, pcode, end, ctx);
return ret;
}
diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h
index 883938a74aee..982d32a5df8b 100644
--- a/kernel/trace/trace_probe.h
+++ b/kernel/trace/trace_probe.h
@@ -435,8 +435,11 @@ struct traceprobe_parse_context {
struct trace_probe *tp;
unsigned int flags;
int offset;
+ int nested_level;
};
+#define TRACEPROBE_MAX_NESTED_LEVEL 3
+
extern int traceprobe_parse_probe_arg(struct trace_probe *tp, int i,
const char *argv,
struct traceprobe_parse_context *ctx);
@@ -571,7 +574,9 @@ extern int traceprobe_define_arg_fields(struct trace_event_call *event_call,
C(TOO_MANY_ARGS, "Too many arguments are specified"), \
C(TOO_MANY_EARGS, "Too many entry arguments specified"), \
C(EVENT_TOO_BIG, "Event too big (too many fields?)"), \
- C(TYPECAST_NOT_EVENT, "Typecasts are only for eprobe fields"),
+ C(TYPECAST_NOT_EVENT, "Typecasts are only for eprobe fields"), \
+ C(TYPECAST_REQ_FIELD, "Typecast requires a field access"), \
+ C(TOO_MANY_NESTED, "Too many nested typecasts/dereferences"),
#undef C
#define C(a, b) TP_ERR_##a
^ permalink raw reply related
* [PATCH v3 4/7] tracing/probes: Support field specifier option for typecast
From: Masami Hiramatsu (Google) @ 2026-06-14 14:54 UTC (permalink / raw)
To: Steven Rostedt, Mathieu Desnoyers
Cc: Jonathan Corbet, Shuah Khan, Masami Hiramatsu, linux-kernel,
linux-trace-kernel, linux-doc, linux-kselftest
In-Reply-To: <178144880282.159464.16882854283219530040.stgit@devnote2>
From: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Add a field specifier option for the typecast. This works like
container_of() macro.
(STRUCT[,FIELD[.FIELD2...]])VAR
This is equivalent to :
container_of(VAR, struct STRUCT, FIELD[.FIELD2...])
For example:
echo "f tick_nohz_handler next_tick=(tick_sched,sched_timer)timer->next_tick" >> dynamic_events
This will trace tick_nohz_handler() with its tick_sched::next_tick which
is converted from @timer by contianer_of(tick, struct tick_sched, sched_timer).
So, if you enabkle both fprobes:tick_nohz_handler__entry and
timer:hrtimer_expire_entry events, we will see something like:
<idle>-0 [002] d.h1. 3778.087272: hrtimer_expire_entry: hrtimer=00000000d63db328 f
unction=tick_nohz_handler now=3777450051040
<idle>-0 [002] d.h1. 3778.087281: tick_nohz_handler__entry: (tick_nohz_handler+0x4
/0x140) next_tick=3777450000000
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
---
Changes in v3:
- Fix error caret position.
Changes in v2:
- Use byteoffset for typecast field offset instead of bitoffset. This fixes negative modulo calculation.
- Check whether a field is specified after typecast.
- Reject if typecast field option has arrow operator.
---
Documentation/trace/eprobetrace.rst | 5 +
Documentation/trace/fprobetrace.rst | 8 +-
Documentation/trace/kprobetrace.rst | 8 +-
kernel/trace/trace.c | 4 -
kernel/trace/trace_probe.c | 179 ++++++++++++++++++++++++-----------
kernel/trace/trace_probe.h | 5 +
6 files changed, 142 insertions(+), 67 deletions(-)
diff --git a/Documentation/trace/eprobetrace.rst b/Documentation/trace/eprobetrace.rst
index cd0b4aa7f896..680e0af43d5d 100644
--- a/Documentation/trace/eprobetrace.rst
+++ b/Documentation/trace/eprobetrace.rst
@@ -49,7 +49,10 @@ Synopsis of eprobe_events
(STRUCT)FIELD->MEMBER[->MEMBER] : If BTF is supported, typecast FIELD to
a pointer to STRUCT and then derference the pointer defined by
->MEMBER. Note that when this is used, the FIELD name does not
- need to be prefixed with a '$'.
+ need to be prefixed with a '$'. ASGN can be specified optionally.
+ If ASGN is specified, FIELD will be cast to the same offset
+ position as the ASGN member, rather than to the beginning of
+ the STRUCT.
(STRUCT)(FETCHARG)->MEMBER[->MEMBER] : typecast can nest, so the above can
also be used with another FETCHARG instead of FIELD.
diff --git a/Documentation/trace/fprobetrace.rst b/Documentation/trace/fprobetrace.rst
index 6b8bb27bb62d..290a9e6f7491 100644
--- a/Documentation/trace/fprobetrace.rst
+++ b/Documentation/trace/fprobetrace.rst
@@ -57,10 +57,12 @@ Synopsis of fprobe-events
(u8/u16/u32/u64/s8/s16/s32/s64), hexadecimal types
(x8/x16/x32/x64), "char", "string", "ustring", "symbol", "symstr"
and bitfield are supported.
- (STRUCT)FIELD->MEMBER[->MEMBER] : If BTF is supported, typecast FIELD to
+ (STRUCT[,ASGN])FIELD->MEMBER[->MEMBER] : If BTF is supported, typecast FIELD to
a pointer to STRUCT and then derference the pointer defined by
- ->MEMBER.
- (STRUCT)(FETCHARG)->MEMBER[->MEMBER] : typecast can nest, so the above can
+ ->MEMBER. ASGN can be specified optionally. If ASGN is specified,
+ FIELD will be cast to the same offset position as the ASGN member,
+ rather than to the beginning of the STRUCT.
+ (STRUCT[,ASGN])(FETCHARG)->MEMBER[->MEMBER] : typecast can nest, so the above can
also be used with another FETCHARG instead of FIELD.
(\*1) This is available only when BTF is enabled.
diff --git a/Documentation/trace/kprobetrace.rst b/Documentation/trace/kprobetrace.rst
index c4382765d5b2..a62707e6a9f2 100644
--- a/Documentation/trace/kprobetrace.rst
+++ b/Documentation/trace/kprobetrace.rst
@@ -61,11 +61,13 @@ Synopsis of kprobe_events
(x8/x16/x32/x64), VFS layer common type(%pd/%pD), "char",
"string", "ustring", "symbol", "symstr" and bitfield are
supported.
- (STRUCT)FIELD->MEMBER[->MEMBER] : If BTF is supported, typecast FIELD to
+ (STRUCT[,ASGN])FIELD->MEMBER[->MEMBER] : If BTF is supported, typecast FIELD to
a pointer to STRUCT and then derference the pointer defined by
->MEMBER. Note that this is available only when the probe is
- on function entry.
- (STRUCT)(FETCHARG)->MEMBER[->MEMBER] : typecast can nest, so the above can
+ on function entry. ASGN can be specified optionally. If ASGN
+ is specified, FIELD will be cast to the same offset position
+ as the ASGN member, rather than to the beginning of the STRUCT.
+ (STRUCT[,ASGN])(FETCHARG)->MEMBER[->MEMBER] : typecast can nest, so the above can
also be used with another FETCHARG instead of FIELD.
(\*1) only for the probe on function entry (offs == 0). Note, this argument access
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 4f70318918c2..0e36af853199 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -4325,8 +4325,8 @@ static const char readme_msg[] =
#ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API
"\t $stack<index>, $stack, $retval, $comm, $arg<N>,\n"
#ifdef CONFIG_PROBE_EVENTS_BTF_ARGS
- "\t [(structname)]<argname>[->field[->field|.field...]],\n"
- "\t [(structname)](fetcharg)->field[->field|.field...],\n"
+ "\t [(structname[,field])]<argname>[->field[->field|.field...]],\n"
+ "\t [(structname[,field])](fetcharg)->field[->field|.field...],\n"
#endif
#else
"\t $stack<index>, $stack, $retval, $comm,\n"
diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
index dba73aaa8ade..3ead93de2d93 100644
--- a/kernel/trace/trace_probe.c
+++ b/kernel/trace/trace_probe.c
@@ -574,6 +574,65 @@ static int split_next_field(char *varname, char **next_field,
return ret;
}
+/* Inner loop for solving dot operator ('.'). Return bit-offset of the given field */
+static int get_bitoffset_of_field(char **pfieldname, const struct btf_type **ptype,
+ struct traceprobe_parse_context *ctx)
+{
+ const struct btf_type *type = *ptype;
+ const struct btf_member *field;
+ struct btf *btf = ctx_btf(ctx);
+ char *fieldname = *pfieldname;
+ int bitoffs = 0;
+ u32 anon_offs;
+ char *next;
+ int is_ptr;
+ s32 tid;
+
+ do {
+ next = NULL;
+ is_ptr = split_next_field(fieldname, &next, ctx);
+ if (is_ptr < 0)
+ return is_ptr;
+
+ anon_offs = 0;
+ field = btf_find_struct_member(btf, type, fieldname,
+ &anon_offs);
+ if (IS_ERR(field)) {
+ trace_probe_log_err(ctx->offset, BAD_BTF_TID);
+ return PTR_ERR(field);
+ }
+ if (!field) {
+ trace_probe_log_err(ctx->offset, NO_BTF_FIELD);
+ return -ENOENT;
+ }
+ /* Add anonymous structure/union offset */
+ bitoffs += anon_offs;
+
+ /* Accumulate the bit-offsets of the dot-connected fields */
+ if (btf_type_kflag(type)) {
+ bitoffs += BTF_MEMBER_BIT_OFFSET(field->offset);
+ ctx->last_bitsize = BTF_MEMBER_BITFIELD_SIZE(field->offset);
+ } else {
+ bitoffs += field->offset;
+ ctx->last_bitsize = 0;
+ }
+
+ type = btf_type_skip_modifiers(btf, field->type, &tid);
+ if (!type) {
+ trace_probe_log_err(ctx->offset, BAD_BTF_TID);
+ return -EINVAL;
+ }
+
+ if (next)
+ ctx->offset += next - fieldname;
+ fieldname = next;
+ } while (!is_ptr && fieldname);
+
+ *pfieldname = fieldname;
+ *ptype = type;
+
+ return bitoffs;
+}
/*
* Parse the field of data structure. The @type must be a pointer type
* pointing the target data structure type.
@@ -583,16 +642,14 @@ static int parse_btf_field(char *fieldname, const struct btf_type *type,
struct traceprobe_parse_context *ctx)
{
struct fetch_insn *code = *pcode;
- const struct btf_member *field;
- u32 bitoffs, anon_offs;
- bool is_struct = ctx->struct_btf != NULL;
struct btf *btf = ctx_btf(ctx);
- char *next;
- int is_ptr;
+ bool is_first_field = true;
+ int bitoffs;
s32 tid;
do {
- if (!is_struct) {
+ /* For the first field of typecast, @type will be the target structure type. */
+ if (!(is_first_field && ctx->struct_btf)) {
/* Outer loop for solving arrow operator ('->') */
if (BTF_INFO_KIND(type->info) != BTF_KIND_PTR) {
trace_probe_log_err(ctx->offset, NO_PTR_STRCT);
@@ -606,60 +663,25 @@ static int parse_btf_field(char *fieldname, const struct btf_type *type,
return -EINVAL;
}
}
- /* Only the first type can skip being a pointer */
- is_struct = false;
-
- bitoffs = 0;
- do {
- /* Inner loop for solving dot operator ('.') */
- next = NULL;
- is_ptr = split_next_field(fieldname, &next, ctx);
- if (is_ptr < 0)
- return is_ptr;
-
- anon_offs = 0;
- field = btf_find_struct_member(btf, type, fieldname,
- &anon_offs);
- if (IS_ERR(field)) {
- trace_probe_log_err(ctx->offset, BAD_BTF_TID);
- return PTR_ERR(field);
- }
- if (!field) {
- trace_probe_log_err(ctx->offset, NO_BTF_FIELD);
- return -ENOENT;
- }
- /* Add anonymous structure/union offset */
- bitoffs += anon_offs;
-
- /* Accumulate the bit-offsets of the dot-connected fields */
- if (btf_type_kflag(type)) {
- bitoffs += BTF_MEMBER_BIT_OFFSET(field->offset);
- ctx->last_bitsize = BTF_MEMBER_BITFIELD_SIZE(field->offset);
- } else {
- bitoffs += field->offset;
- ctx->last_bitsize = 0;
- }
-
- type = btf_type_skip_modifiers(btf, field->type, &tid);
- if (!type) {
- trace_probe_log_err(ctx->offset, BAD_BTF_TID);
- return -EINVAL;
- }
-
- ctx->offset += next - fieldname;
- fieldname = next;
- } while (!is_ptr && fieldname);
+ bitoffs = get_bitoffset_of_field(&fieldname, &type, ctx);
+ if (bitoffs < 0)
+ return bitoffs;
if (++code == end) {
trace_probe_log_err(ctx->offset, TOO_MANY_OPS);
return -EINVAL;
}
code->op = FETCH_OP_DEREF; /* TODO: user deref support */
code->offset = bitoffs / 8;
+ if (is_first_field && ctx->struct_btf) {
+ /* The first field can be typecasted with field option. */
+ code->offset -= ctx->prefix_byteoffs;
+ }
*pcode = code;
ctx->last_bitoffs = bitoffs % 8;
ctx->last_type = type;
+ is_first_field = false;
} while (fieldname);
return 0;
@@ -690,6 +712,11 @@ static int parse_btf_arg(char *varname,
NOSUP_DAT_ARG);
return -EOPNOTSUPP;
}
+ if (!field && ctx->struct_btf) {
+ /* Typecast without field option is not supported */
+ trace_probe_log_err(ctx->offset + strlen(varname), TYPECAST_REQ_FIELD);
+ return -EOPNOTSUPP;
+ }
if (ctx->flags & TPARG_FL_TEVENT) {
ret = parse_trace_event(varname, code, ctx);
@@ -700,8 +727,7 @@ static int parse_btf_arg(char *varname,
/* TEVENT is only here via a typecast */
if (WARN_ON_ONCE(ctx->struct_btf == NULL))
return -EINVAL;
- type = ctx->last_struct;
- goto found_type;
+ goto found;
}
if (ctx->flags & TPARG_FL_RETURN && !strcmp(varname, "$retval")) {
@@ -763,7 +789,6 @@ static int parse_btf_arg(char *varname,
type = ctx->last_struct;
else
type = btf_type_skip_modifiers(ctx->btf, tid, &tid);
-found_type:
if (!type) {
trace_probe_log_err(ctx->offset, BAD_BTF_TID);
return -EINVAL;
@@ -832,6 +857,46 @@ static int query_btf_struct(const char *sname, struct traceprobe_parse_context *
return 0;
}
+static int parse_btf_casttype(char *casttype, struct traceprobe_parse_context *ctx)
+{
+ char *field;
+ int ret;
+
+ /* Field option - evaluated later. */
+ field = strchr(casttype, ',');
+ if (field)
+ *field++ = '\0';
+
+ ret = query_btf_struct(casttype, ctx);
+ if (ret < 0) {
+ trace_probe_log_err(ctx->offset, NO_PTR_STRCT);
+ return -EINVAL;
+ }
+
+ if (field) {
+ struct btf_type *type = (struct btf_type *)ctx->last_struct;
+
+ ctx->offset += field - casttype;
+ ret = get_bitoffset_of_field(&field, &ctx->last_struct, ctx);
+ if (ret < 0)
+ return ret;
+ if (ret % 8) {
+ trace_probe_log_err(ctx->offset, TYPECAST_NOT_ALIGNED);
+ return -EINVAL;
+ }
+ if (field != NULL) {
+ /* this means @field skips an arrow operator ("->"). */
+ trace_probe_log_err(ctx->offset - 2, TYPECAST_BAD_ARROW);
+ return -EINVAL;
+ }
+ ctx->prefix_byteoffs = ret / 8;
+ /* Restore the original struct type (overwritten by get_bitoffset_of_field) */
+ ctx->last_struct = type;
+ }
+
+ return ret;
+}
+
/* Find the matching closing parenthesis for a given opening parenthesis. */
static char *find_matched_close_paren(char *s)
{
@@ -915,11 +980,10 @@ static int handle_typecast(char *arg, struct fetch_insn **pcode,
nested = true;
}
- ret = query_btf_struct(arg + 1, ctx);
- if (ret < 0) {
- trace_probe_log_err(ctx->offset + 1, NO_PTR_STRCT);
- return -EINVAL;
- }
+ ctx->offset = orig_offset + 1; /* for the '(' */
+ ret = parse_btf_casttype(arg + 1, ctx);
+ if (ret < 0)
+ return ret;
ctx->offset = orig_offset + tmp - arg;
/* If it is nested, tmp points to the field name. */
@@ -927,6 +991,7 @@ static int handle_typecast(char *arg, struct fetch_insn **pcode,
ret = parse_btf_field(tmp, ctx->last_struct, pcode, end, ctx);
else
ret = parse_btf_arg(tmp, pcode, end, ctx);
+ ctx->prefix_byteoffs = 0;
return ret;
}
diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h
index 982d32a5df8b..44f113faae61 100644
--- a/kernel/trace/trace_probe.h
+++ b/kernel/trace/trace_probe.h
@@ -436,6 +436,7 @@ struct traceprobe_parse_context {
unsigned int flags;
int offset;
int nested_level;
+ int prefix_byteoffs; /* The byte offset of the prefix field of typecast */
};
#define TRACEPROBE_MAX_NESTED_LEVEL 3
@@ -576,7 +577,9 @@ extern int traceprobe_define_arg_fields(struct trace_event_call *event_call,
C(EVENT_TOO_BIG, "Event too big (too many fields?)"), \
C(TYPECAST_NOT_EVENT, "Typecasts are only for eprobe fields"), \
C(TYPECAST_REQ_FIELD, "Typecast requires a field access"), \
- C(TOO_MANY_NESTED, "Too many nested typecasts/dereferences"),
+ C(TOO_MANY_NESTED, "Too many nested typecasts/dereferences"), \
+ C(TYPECAST_NOT_ALIGNED, "Typecast field option is not byte-aligned"), \
+ C(TYPECAST_BAD_ARROW, "Typecast field option does not support -> operator"),
#undef C
#define C(a, b) TP_ERR_##a
^ permalink raw reply related
* [PATCH v3 5/7] tracing/probes: Add $current variable support
From: Masami Hiramatsu (Google) @ 2026-06-14 14:54 UTC (permalink / raw)
To: Steven Rostedt, Mathieu Desnoyers
Cc: Jonathan Corbet, Shuah Khan, Masami Hiramatsu, linux-kernel,
linux-trace-kernel, linux-doc, linux-kselftest
In-Reply-To: <178144880282.159464.16882854283219530040.stgit@devnote2>
From: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Since we can use the BTF to cast value to a structure pointer type,
it is useful to introduce "$current" special variable support to
fetcharg.
User can define a fetcharg to access current task_struct properties
using BTF info. e.g.
$current->cpus_ptr
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
---
Changes in v3:
- Remove $current support from eprobes (because eprobes is only for event)
- Prohibit uprobes to use $current.
Changes in v2:
- Support to parse $current in parse_btf_arg().
- If no typecast on $current, it automatically casted to task_struct.
- Check error case if $current follows something except for "-".
---
Documentation/trace/fprobetrace.rst | 1 +
Documentation/trace/kprobetrace.rst | 1 +
kernel/trace/trace.c | 2 +-
kernel/trace/trace_probe.c | 34 +++++++++++++++++++++++++++++++++-
kernel/trace/trace_probe.h | 1 +
kernel/trace/trace_probe_tmpl.h | 3 +++
6 files changed, 40 insertions(+), 2 deletions(-)
diff --git a/Documentation/trace/fprobetrace.rst b/Documentation/trace/fprobetrace.rst
index 290a9e6f7491..3392cab016b3 100644
--- a/Documentation/trace/fprobetrace.rst
+++ b/Documentation/trace/fprobetrace.rst
@@ -50,6 +50,7 @@ Synopsis of fprobe-events
$argN : Fetch the Nth function argument. (N >= 1) (\*2)
$retval : Fetch return value.(\*3)
$comm : Fetch current task comm.
+ $current : Fetch the address of the current task_struct.
+|-[u]OFFS(FETCHARG) : Fetch memory at FETCHARG +|- OFFS address.(\*4)(\*5)
\IMM : Store an immediate value to the argument.
NAME=FETCHARG : Set NAME as the argument name of FETCHARG.
diff --git a/Documentation/trace/kprobetrace.rst b/Documentation/trace/kprobetrace.rst
index a62707e6a9f2..81e4fe38791d 100644
--- a/Documentation/trace/kprobetrace.rst
+++ b/Documentation/trace/kprobetrace.rst
@@ -53,6 +53,7 @@ Synopsis of kprobe_events
$argN : Fetch the Nth function argument. (N >= 1) (\*1)
$retval : Fetch return value.(\*2)
$comm : Fetch current task comm.
+ $current : Fetch the address of the current task_struct.
+|-[u]OFFS(FETCHARG) : Fetch memory at FETCHARG +|- OFFS address.(\*3)(\*4)
\IMM : Store an immediate value to the argument.
NAME=FETCHARG : Set NAME as the argument name of FETCHARG.
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 0e36af853199..e185a006cb08 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -4329,7 +4329,7 @@ static const char readme_msg[] =
"\t [(structname[,field])](fetcharg)->field[->field|.field...],\n"
#endif
#else
- "\t $stack<index>, $stack, $retval, $comm,\n"
+ "\t $stack<index>, $stack, $retval, $comm, $current\n"
#endif
"\t +|-[u]<offset>(<fetcharg>), \\imm-value, \\\"imm-string\"\n"
"\t kernel return probes support: $retval, $arg<N>, $comm\n"
diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
index 3ead93de2d93..017f30ae9def 100644
--- a/kernel/trace/trace_probe.c
+++ b/kernel/trace/trace_probe.c
@@ -718,6 +718,20 @@ static int parse_btf_arg(char *varname,
return -EOPNOTSUPP;
}
+ if (strcmp(varname, "$current") == 0) {
+ code->op = FETCH_OP_CURRENT;
+ /* If no typecast is specified for $current, use task_struct by default */
+ if (!ctx->struct_btf) {
+ tid = bpf_find_btf_id("task_struct", BTF_KIND_STRUCT, &ctx->struct_btf);
+ if (tid < 0) {
+ trace_probe_log_err(ctx->offset, NO_BTF_ENTRY);
+ return -ENOENT;
+ }
+ ctx->last_struct = btf_type_skip_modifiers(ctx->struct_btf, tid, &tid);
+ }
+ goto found;
+ }
+
if (ctx->flags & TPARG_FL_TEVENT) {
ret = parse_trace_event(varname, code, ctx);
if (ret < 0) {
@@ -756,8 +770,8 @@ static int parse_btf_arg(char *varname,
return -ENOENT;
}
}
- params = ctx->params;
+ params = ctx->params;
for (i = 0; i < ctx->nr_params; i++) {
const char *name = btf_name_by_offset(ctx->btf, params[i].name_off);
@@ -1247,6 +1261,24 @@ static int parse_probe_vars(char *orig_arg, const struct fetch_type *t,
return 0;
}
+ /* $current returns the address of the current task_struct. */
+ if (str_has_prefix(arg, "current")) {
+ /* $current is only supported by kernel probe. */
+ if (!(ctx->flags & TPARG_FL_KERNEL)) {
+ err = TP_ERR_BAD_VAR;
+ goto inval;
+ }
+ arg += strlen("current");
+ if (*arg == '-' && IS_ENABLED(CONFIG_PROBE_EVENTS_BTF_ARGS))
+ return parse_btf_arg(orig_arg, pcode, end, ctx);
+
+ if (*arg != '\0')
+ goto inval;
+
+ code->op = FETCH_OP_CURRENT;
+ return 0;
+ }
+
#ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API
len = str_has_prefix(arg, "arg");
if (len) {
diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h
index 44f113faae61..62645e847bd1 100644
--- a/kernel/trace/trace_probe.h
+++ b/kernel/trace/trace_probe.h
@@ -96,6 +96,7 @@ enum fetch_op {
FETCH_OP_FOFFS, /* File offset: .immediate */
FETCH_OP_DATA, /* Allocated data: .data */
FETCH_OP_EDATA, /* Entry data: .offset */
+ FETCH_OP_CURRENT, /* Current task_struct address */
// Stage 2 (dereference) op
FETCH_OP_DEREF, /* Dereference: .offset */
FETCH_OP_UDEREF, /* User-space Dereference: .offset */
diff --git a/kernel/trace/trace_probe_tmpl.h b/kernel/trace/trace_probe_tmpl.h
index f39b37fcdb3b..f630930288d2 100644
--- a/kernel/trace/trace_probe_tmpl.h
+++ b/kernel/trace/trace_probe_tmpl.h
@@ -112,6 +112,9 @@ process_common_fetch_insn(struct fetch_insn *code, unsigned long *val)
case FETCH_OP_DATA:
*val = (unsigned long)code->data;
break;
+ case FETCH_OP_CURRENT:
+ *val = (unsigned long)current;
+ break;
default:
return -EILSEQ;
}
^ permalink raw reply related
* [PATCH v3 6/7] tracing/probes: Add this_cpu_read() and this_cpu_ptr() dereference method to fetcharg
From: Masami Hiramatsu (Google) @ 2026-06-14 14:54 UTC (permalink / raw)
To: Steven Rostedt, Mathieu Desnoyers
Cc: Jonathan Corbet, Shuah Khan, Masami Hiramatsu, linux-kernel,
linux-trace-kernel, linux-doc, linux-kselftest
In-Reply-To: <178144880282.159464.16882854283219530040.stgit@devnote2>
From: Masami Hiramatsu (Google) <mhiramat@kernel.org>
When tracing the kernel local variables, sometimes we need to get the
CPU local variables. To access it, current simple dereference is not
enough.
Thus, introduce a special this_cpu_read() dereference to access per-cpu
variable for the current CPU (accessing other CPU variable may race with
updates on other CPUs). Also this_cpu_ptr() is for accessing per-cpu
pointer.
Those are working as same as the kernel percpu macro.
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
---
Changes in v3:
- Remove NULL check for percpu var because it is just an offset, could be 0.
- Simplify process_fetch_insn_bottom() code.
- If the last operation is this_cpu_read(), read only memory of the specific
size (of type).
Changes in v2:
- Drop +CPU/+PCPU and introduce this_cpu_read() and this_cpu_ptr().
- Support these method with BTF typecast.
- Just check the base address is NOT NULL instead of is_kernel_percpu_address().
---
Documentation/trace/eprobetrace.rst | 2 +
Documentation/trace/fprobetrace.rst | 2 +
Documentation/trace/kprobetrace.rst | 2 +
kernel/trace/trace.c | 1
kernel/trace/trace_probe.c | 138 ++++++++++++++++++++++++-----------
kernel/trace/trace_probe.h | 3 +
kernel/trace/trace_probe_tmpl.h | 30 ++++++--
7 files changed, 129 insertions(+), 49 deletions(-)
diff --git a/Documentation/trace/eprobetrace.rst b/Documentation/trace/eprobetrace.rst
index 680e0af43d5d..279396951b34 100644
--- a/Documentation/trace/eprobetrace.rst
+++ b/Documentation/trace/eprobetrace.rst
@@ -39,6 +39,8 @@ Synopsis of eprobe_events
@SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol)
$comm : Fetch current task comm.
+|-[u]OFFS(FETCHARG) : Fetch memory at FETCHARG +|- OFFS address.(\*3)(\*4)
+ this_cpu_read(FETCHARG) : Read the value of the per-CPU variable FETCHARG on the current CPU.
+ this_cpu_ptr(FETCHARG) : Get the address of the per-CPU variable FETCHARG on the current CPU.
\IMM : Store an immediate value to the argument.
NAME=FETCHARG : Set NAME as the argument name of FETCHARG.
FETCHARG:TYPE : Set TYPE as the type of FETCHARG. Currently, basic types
diff --git a/Documentation/trace/fprobetrace.rst b/Documentation/trace/fprobetrace.rst
index 3392cab016b3..3439bc9bd351 100644
--- a/Documentation/trace/fprobetrace.rst
+++ b/Documentation/trace/fprobetrace.rst
@@ -52,6 +52,8 @@ Synopsis of fprobe-events
$comm : Fetch current task comm.
$current : Fetch the address of the current task_struct.
+|-[u]OFFS(FETCHARG) : Fetch memory at FETCHARG +|- OFFS address.(\*4)(\*5)
+ this_cpu_read(FETCHARG) : Read the value of the per-CPU variable FETCHARG on the current CPU.
+ this_cpu_ptr(FETCHARG) : Get the address of the per-CPU variable FETCHARG on the current CPU.
\IMM : Store an immediate value to the argument.
NAME=FETCHARG : Set NAME as the argument name of FETCHARG.
FETCHARG:TYPE : Set TYPE as the type of FETCHARG. Currently, basic types
diff --git a/Documentation/trace/kprobetrace.rst b/Documentation/trace/kprobetrace.rst
index 81e4fe38791d..9ae330eb0a52 100644
--- a/Documentation/trace/kprobetrace.rst
+++ b/Documentation/trace/kprobetrace.rst
@@ -55,6 +55,8 @@ Synopsis of kprobe_events
$comm : Fetch current task comm.
$current : Fetch the address of the current task_struct.
+|-[u]OFFS(FETCHARG) : Fetch memory at FETCHARG +|- OFFS address.(\*3)(\*4)
+ this_cpu_read(FETCHARG) : Read the value of the per-CPU variable FETCHARG on the current CPU.
+ this_cpu_ptr(FETCHARG) : Get the address of the per-CPU variable FETCHARG on the current CPU.
\IMM : Store an immediate value to the argument.
NAME=FETCHARG : Set NAME as the argument name of FETCHARG.
FETCHARG:TYPE : Set TYPE as the type of FETCHARG. Currently, basic types
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index e185a006cb08..1d5d6e46dc4d 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -4332,6 +4332,7 @@ static const char readme_msg[] =
"\t $stack<index>, $stack, $retval, $comm, $current\n"
#endif
"\t +|-[u]<offset>(<fetcharg>), \\imm-value, \\\"imm-string\"\n"
+ "\t this_cpu_read(<fetcharg>), this_cpu_ptr(<fetcharg>)\n"
"\t kernel return probes support: $retval, $arg<N>, $comm\n"
"\t type: s8/16/32/64, u8/16/32/64, x8/16/32/64, char, string, symbol,\n"
"\t b<bit-width>@<bit-offset>/<container-size>, ustring,\n"
diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
index 017f30ae9def..61bd65575f64 100644
--- a/kernel/trace/trace_probe.c
+++ b/kernel/trace/trace_probe.c
@@ -349,6 +349,77 @@ static int parse_trace_event(char *arg, struct fetch_insn *code,
return -EINVAL;
}
+/* this_cpu_* parser */
+#define THIS_CPU_PTR_PREFIX "this_cpu_ptr("
+#define THIS_CPU_READ_PREFIX "this_cpu_read("
+#define THIS_CPU_PTR_LEN (sizeof(THIS_CPU_PTR_PREFIX) - 1)
+#define THIS_CPU_READ_LEN (sizeof(THIS_CPU_READ_PREFIX) - 1)
+
+static int
+parse_probe_arg(char *arg, const struct fetch_type *type,
+ struct fetch_insn **pcode, struct fetch_insn *end,
+ struct traceprobe_parse_context *ctx);
+
+/* handle dereference nested call */
+static inline int handle_dereference(char *arg, struct fetch_insn **pcode,
+ struct fetch_insn *end, struct traceprobe_parse_context *ctx,
+ int deref, long offset)
+{
+ const struct fetch_type *type = find_fetch_type(NULL, ctx->flags);
+ struct fetch_insn *code = *pcode;
+ int cur_offs = ctx->offset;
+ char *tmp;
+ int ret;
+
+ tmp = strrchr(arg, ')');
+ if (!tmp) {
+ trace_probe_log_err(ctx->offset + strlen(arg),
+ DEREF_OPEN_BRACE);
+ return -EINVAL;
+ }
+
+ *tmp = '\0';
+ ret = parse_probe_arg(arg, type, &code, end, ctx);
+ if (ret)
+ return ret;
+ ctx->offset = cur_offs;
+ if (code->op == FETCH_OP_COMM || code->op == FETCH_OP_DATA) {
+ trace_probe_log_err(ctx->offset, COMM_CANT_DEREF);
+ return -EINVAL;
+ }
+ code++;
+ if (code == end) {
+ trace_probe_log_err(ctx->offset, TOO_MANY_OPS);
+ return -EINVAL;
+ }
+ *pcode = code;
+
+ code->op = deref;
+ code->offset = offset;
+ /* Reset the last type if used */
+ ctx->last_type = NULL;
+ return 0;
+}
+
+static int parse_this_cpu(char *arg, struct fetch_insn **pcode,
+ struct fetch_insn *end,
+ struct traceprobe_parse_context *ctx)
+{
+ int deref;
+
+ if (str_has_prefix(arg, THIS_CPU_PTR_PREFIX)) {
+ arg += THIS_CPU_PTR_LEN;
+ ctx->offset += THIS_CPU_PTR_LEN;
+ deref = FETCH_OP_CPU_PTR;
+ } else if (str_has_prefix(arg, THIS_CPU_READ_PREFIX)) {
+ arg += THIS_CPU_READ_LEN;
+ ctx->offset += THIS_CPU_READ_LEN;
+ deref = FETCH_OP_DEREF_CPU;
+ } else
+ return -EINVAL;
+ return handle_dereference(arg, pcode, end, ctx, deref, 0);
+}
+
#ifdef CONFIG_PROBE_EVENTS_BTF_ARGS
static u32 btf_type_int(const struct btf_type *t)
@@ -929,11 +1000,6 @@ static char *find_matched_close_paren(char *s)
return NULL;
}
-static int
-parse_probe_arg(char *arg, const struct fetch_type *type,
- struct fetch_insn **pcode, struct fetch_insn *end,
- struct traceprobe_parse_context *ctx);
-
static int handle_typecast(char *arg, struct fetch_insn **pcode,
struct fetch_insn *end,
struct traceprobe_parse_context *ctx)
@@ -959,7 +1025,8 @@ static int handle_typecast(char *arg, struct fetch_insn **pcode,
*tmp++ = '\0';
/* Handle the nested structure like (STRUCT)(VAR->FIELD)->... */
- if (*tmp == '(') {
+ if (*tmp == '(' || str_has_prefix(tmp, THIS_CPU_PTR_PREFIX) ||
+ str_has_prefix(tmp, THIS_CPU_READ_PREFIX)) {
char *close = find_matched_close_paren(tmp);
ctx->offset += tmp - arg;
@@ -979,12 +1046,18 @@ static int handle_typecast(char *arg, struct fetch_insn **pcode,
trace_probe_log_err(ctx->offset, TOO_MANY_NESTED);
return -E2BIG;
}
- *close = '\0';
- ctx->offset += 1; /* for the '(' */
- /* We need to parse the nested one */
- ret = parse_probe_arg(tmp + 1, find_fetch_type(NULL, ctx->flags),
- pcode, end, ctx);
+ if (*tmp == '(') {
+ /* Extract the inner argument */
+ *close = '\0';
+ ctx->offset += 1;/* for the '(' */
+ /* Parse the nested one */
+ ret = parse_probe_arg(tmp + 1, find_fetch_type(NULL, ctx->flags),
+ pcode, end, ctx);
+ } else {
+ /* this_cpu_* will be parsed in parse_this_cpu() */
+ ret = parse_this_cpu(tmp, pcode, end, ctx);
+ }
if (ret < 0)
return ret;
ctx->nested_level--;
@@ -1454,36 +1527,9 @@ parse_probe_arg(char *arg, const struct fetch_type *type,
}
ctx->offset += (tmp + 1 - arg) + (arg[0] != '-' ? 1 : 0);
arg = tmp + 1;
- tmp = strrchr(arg, ')');
- if (!tmp) {
- trace_probe_log_err(ctx->offset + strlen(arg),
- DEREF_OPEN_BRACE);
- return -EINVAL;
- } else {
- const struct fetch_type *t2 = find_fetch_type(NULL, ctx->flags);
- int cur_offs = ctx->offset;
-
- *tmp = '\0';
- ret = parse_probe_arg(arg, t2, &code, end, ctx);
- if (ret)
- break;
- ctx->offset = cur_offs;
- if (code->op == FETCH_OP_COMM ||
- code->op == FETCH_OP_DATA) {
- trace_probe_log_err(ctx->offset, COMM_CANT_DEREF);
- return -EINVAL;
- }
- if (++code == end) {
- trace_probe_log_err(ctx->offset, TOO_MANY_OPS);
- return -EINVAL;
- }
- *pcode = code;
-
- code->op = deref;
- code->offset = offset;
- /* Reset the last type if used */
- ctx->last_type = NULL;
- }
+ ret = handle_dereference(arg, pcode, end, ctx, deref, offset);
+ if (ret < 0)
+ return ret;
break;
case '\\': /* Immediate value */
if (arg[1] == '"') { /* Immediate string */
@@ -1504,15 +1550,18 @@ parse_probe_arg(char *arg, const struct fetch_type *type,
ret = handle_typecast(arg, pcode, end, ctx);
break;
default:
- if (isalpha(arg[0]) || arg[0] == '_') { /* BTF variable */
+ if (str_has_prefix(arg, THIS_CPU_PTR_PREFIX) ||
+ str_has_prefix(arg, THIS_CPU_READ_PREFIX)) {
+ ret = parse_this_cpu(arg, pcode, end, ctx);
+ } else if (isalpha(arg[0]) || arg[0] == '_') { /* BTF variable */
if (!tparg_is_function_entry(ctx->flags) &&
!tparg_is_function_return(ctx->flags)) {
trace_probe_log_err(ctx->offset, NOSUP_BTFARG);
return -EINVAL;
}
ret = parse_btf_arg(arg, pcode, end, ctx);
- break;
}
+ break;
}
if (!ret && code->op == FETCH_OP_NOP) {
/* Parsed, but do not find fetch method */
@@ -1687,6 +1736,9 @@ static int finalize_fetch_insn(struct fetch_insn *code,
} else if (code->op == FETCH_OP_UDEREF) {
code->op = FETCH_OP_ST_UMEM;
code->size = parg->type->size;
+ } else if (code->op == FETCH_OP_DEREF_CPU) {
+ code->op = FETCH_OP_ST_CPUMEM;
+ code->size = parg->type->size;
} else {
code++;
if (code->op != FETCH_OP_NOP) {
diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h
index 62645e847bd1..523612023608 100644
--- a/kernel/trace/trace_probe.h
+++ b/kernel/trace/trace_probe.h
@@ -100,10 +100,13 @@ enum fetch_op {
// Stage 2 (dereference) op
FETCH_OP_DEREF, /* Dereference: .offset */
FETCH_OP_UDEREF, /* User-space Dereference: .offset */
+ FETCH_OP_DEREF_CPU, /* Per-CPU Dereference for this CPU */
+ FETCH_OP_CPU_PTR, /* Per-CPU pointer for this CPU */
// Stage 3 (store) ops
FETCH_OP_ST_RAW, /* Raw: .size */
FETCH_OP_ST_MEM, /* Mem: .offset, .size */
FETCH_OP_ST_UMEM, /* Mem: .offset, .size */
+ FETCH_OP_ST_CPUMEM, /* Per-CPU Mem: .size */
FETCH_OP_ST_STRING, /* String: .offset, .size */
FETCH_OP_ST_USTRING, /* User String: .offset, .size */
FETCH_OP_ST_SYMSTR, /* Kernel Symbol String: .offset, .size */
diff --git a/kernel/trace/trace_probe_tmpl.h b/kernel/trace/trace_probe_tmpl.h
index f630930288d2..83111c167b74 100644
--- a/kernel/trace/trace_probe_tmpl.h
+++ b/kernel/trace/trace_probe_tmpl.h
@@ -129,25 +129,39 @@ process_fetch_insn_bottom(struct fetch_insn *code, unsigned long val,
struct fetch_insn *s3 = NULL;
int total = 0, ret = 0, i = 0;
u32 loc = 0;
- unsigned long lval = val;
+ unsigned long lval, llval = val;
stage2:
/* 2nd stage: dereference memory if needed */
do {
- if (code->op == FETCH_OP_DEREF) {
- lval = val;
+ lval = val;
+ switch (code->op) {
+ case FETCH_OP_DEREF:
ret = probe_mem_read(&val, (void *)val + code->offset,
sizeof(val));
- } else if (code->op == FETCH_OP_UDEREF) {
- lval = val;
+ break;
+ case FETCH_OP_UDEREF:
ret = probe_mem_read_user(&val,
(void *)val + code->offset, sizeof(val));
- } else
break;
+ case FETCH_OP_DEREF_CPU:
+ val = (unsigned long)this_cpu_ptr((void __percpu *)val);
+ ret = probe_mem_read(&val, (void *)val, sizeof(val));
+ break;
+ case FETCH_OP_CPU_PTR:
+ val = (unsigned long)this_cpu_ptr((void __percpu *)val);
+ ret = 0;
+ break;
+ default:
+ lval = llval;
+ goto out;
+ }
if (ret)
return ret;
+ llval = lval;
code++;
} while (1);
+out:
s3 = code;
stage3:
@@ -181,6 +195,10 @@ process_fetch_insn_bottom(struct fetch_insn *code, unsigned long val,
case FETCH_OP_ST_UMEM:
probe_mem_read_user(dest, (void *)val + code->offset, code->size);
break;
+ case FETCH_OP_ST_CPUMEM:
+ val = (unsigned long)this_cpu_ptr((void __percpu *)val);
+ probe_mem_read(dest, (void *)val, code->size);
+ break;
case FETCH_OP_ST_STRING:
loc = *(u32 *)dest;
ret = fetch_store_string(val + code->offset, dest, base);
^ permalink raw reply related
* [PATCH v3 7/7] tracing/probes: Add a new testcase for BTF typecasts
From: Masami Hiramatsu (Google) @ 2026-06-14 14:54 UTC (permalink / raw)
To: Steven Rostedt, Mathieu Desnoyers
Cc: Jonathan Corbet, Shuah Khan, Masami Hiramatsu, linux-kernel,
linux-trace-kernel, linux-doc, linux-kselftest
In-Reply-To: <178144880282.159464.16882854283219530040.stgit@devnote2>
From: Masami Hiramatsu (Google) <mhiramat@kernel.org>
With the introduction of container_of-style BTF typecasting and
per-CPU variable access support in trace probes, we need a way to
verify their functionality and prevent regressions.
Add a new ftrace kselftest and update the trace event sample module
to test and validate these features.
Specifically, update the trace-events-sample module to set up a
periodic timer whose callback accesses a per-CPU counter. Introduce
a new sample trace event, foo_timer_fn, to trace this callback
and log the current counter value.
Then, add a new test case, btf_probe_event.tc, which defines a
dynamic probe on the timer callback. The probe uses BTF typecasting
to recover the parent structure from the timer argument and
this_cpu_read() to fetch the per-CPU counter. The test verifies
the integrity of the implementation by ensuring the values
recorded by the dynamic probe match those from the static tracepoint.
Assisted-by: Antigravity:gemini-3.5-flash
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
---
Changes in v3:
- Add syntax test case.
- Update testcase to use this_cpu_read()
Changes in v2:
- Use timer_shutdown_sync() instead of timer_delete_sync() for teardown.
---
samples/trace_events/trace-events-sample.c | 40 +++++++++++++++-
samples/trace_events/trace-events-sample.h | 34 ++++++++++++-
.../ftrace/test.d/dynevent/btf_probe_event.tc | 51 ++++++++++++++++++++
.../ftrace/test.d/dynevent/fprobe_syntax_errors.tc | 9 ++++
.../ftrace/test.d/kprobe/kprobe_syntax_errors.tc | 9 ++++
.../ftrace/test.d/kprobe/uprobe_syntax_errors.tc | 5 ++
6 files changed, 143 insertions(+), 5 deletions(-)
create mode 100644 tools/testing/selftests/ftrace/test.d/dynevent/btf_probe_event.tc
diff --git a/samples/trace_events/trace-events-sample.c b/samples/trace_events/trace-events-sample.c
index 82344a78e471..651f3e2138ab 100644
--- a/samples/trace_events/trace-events-sample.c
+++ b/samples/trace_events/trace-events-sample.c
@@ -94,6 +94,20 @@ static int simple_thread_fn(void *arg)
static DEFINE_MUTEX(thread_mutex);
static int simple_thread_cnt;
+static struct foo_timer_data *foo_timer_data;
+
+static void sample_timer_cb(struct timer_list *t)
+{
+ struct foo_timer_data *data = container_of(t, struct foo_timer_data, timer);
+
+ get_cpu();
+ trace_foo_timer_fn(data);
+ (*this_cpu_ptr(data->counter))++;
+ put_cpu();
+
+ mod_timer(t, jiffies + HZ);
+}
+
int foo_bar_reg(void)
{
mutex_lock(&thread_mutex);
@@ -133,9 +147,27 @@ void foo_bar_unreg(void)
static int __init trace_event_init(void)
{
+ foo_timer_data = kzalloc_obj(*foo_timer_data, GFP_KERNEL);
+ if (!foo_timer_data)
+ return -ENOMEM;
+
+ foo_timer_data->name = "sample_timer_counter";
+ foo_timer_data->counter = alloc_percpu(int);
+ if (!foo_timer_data->counter) {
+ kfree(foo_timer_data);
+ return -ENOMEM;
+ }
+
+ timer_setup(&foo_timer_data->timer, sample_timer_cb, 0);
+ mod_timer(&foo_timer_data->timer, jiffies + HZ);
+
simple_tsk = kthread_run(simple_thread, NULL, "event-sample");
- if (IS_ERR(simple_tsk))
- return -1;
+ if (IS_ERR(simple_tsk)) {
+ timer_shutdown_sync(&foo_timer_data->timer);
+ free_percpu(foo_timer_data->counter);
+ kfree(foo_timer_data);
+ return PTR_ERR(simple_tsk);
+ }
return 0;
}
@@ -148,6 +180,10 @@ static void __exit trace_event_exit(void)
kthread_stop(simple_tsk_fn);
simple_tsk_fn = NULL;
mutex_unlock(&thread_mutex);
+
+ timer_shutdown_sync(&foo_timer_data->timer);
+ free_percpu(foo_timer_data->counter);
+ kfree(foo_timer_data);
}
module_init(trace_event_init);
diff --git a/samples/trace_events/trace-events-sample.h b/samples/trace_events/trace-events-sample.h
index 1a05fc153353..816848a456a2 100644
--- a/samples/trace_events/trace-events-sample.h
+++ b/samples/trace_events/trace-events-sample.h
@@ -247,12 +247,14 @@
*/
/*
- * It is OK to have helper functions in the file, but they need to be protected
- * from being defined more than once. Remember, this file gets included more
- * than once.
+ * It is OK to have helper functions and data structures in the file, but they
+ * need to be protected from being defined more than once. Remember, this file
+ * gets included more than once.
*/
#ifndef __TRACE_EVENT_SAMPLE_HELPER_FUNCTIONS
#define __TRACE_EVENT_SAMPLE_HELPER_FUNCTIONS
+#include <linux/timer.h>
+
static inline int __length_of(const int *list)
{
int i;
@@ -270,6 +272,13 @@ enum {
TRACE_SAMPLE_BAR = 4,
TRACE_SAMPLE_ZOO = 8,
};
+
+struct foo_timer_data {
+ const char *name;
+ struct timer_list timer;
+ int __percpu *counter;
+};
+
#endif
/*
@@ -595,6 +604,25 @@ TRACE_EVENT(foo_rel_loc,
__get_rel_bitmask(bitmask),
__get_rel_cpumask(cpumask))
);
+
+TRACE_EVENT(foo_timer_fn,
+
+ TP_PROTO(struct foo_timer_data *data),
+
+ TP_ARGS(data),
+
+ TP_STRUCT__entry(
+ __string( name, data->name )
+ __field( int, count )
+ ),
+
+ TP_fast_assign(
+ __assign_str(name);
+ __entry->count = *this_cpu_ptr(data->counter);
+ ),
+
+ TP_printk("name=%s count=%d", __get_str(name), __entry->count)
+);
#endif
/***** NOTICE! The #if protection ends here. *****/
diff --git a/tools/testing/selftests/ftrace/test.d/dynevent/btf_probe_event.tc b/tools/testing/selftests/ftrace/test.d/dynevent/btf_probe_event.tc
new file mode 100644
index 000000000000..96791e120b7d
--- /dev/null
+++ b/tools/testing/selftests/ftrace/test.d/dynevent/btf_probe_event.tc
@@ -0,0 +1,51 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# description: BTF event with typecast and percpu access
+# requires: dynamic_events "this_cpu_read(<fetcharg>)":README "[(structname[,field])]<argname>[->field[->field|.field...]]":README
+
+# Check if the sample module is loaded
+if ! lsmod | grep -q trace_events_sample; then
+ modprobe trace-events-sample || exit_unsupported
+fi
+
+echo 0 > events/enable
+echo > dynamic_events
+
+# The sample_timer_cb(struct timer_list *t) is called.
+# We want to check (STRUCT,FIELD)VAR typecast and this_cpu_read() access.
+# (foo_timer_data,timer)t converts t to struct foo_timer_data * using container_of.
+# data->counter is a per-cpu pointer to int.
+# this_cpu_read(data->counter) should give the value of the counter.
+
+echo 'f:mysample/myevent sample_timer_cb name=(foo_timer_data,timer)t->name:string count=this_cpu_read((foo_timer_data,timer)t->counter)' >> dynamic_events
+
+echo 1 > events/mysample/myevent/enable
+echo 1 > events/sample-trace/foo_timer_fn/enable
+
+sleep 2
+
+echo 0 > events/mysample/myevent/enable
+echo 0 > events/sample-trace/foo_timer_fn/enable
+
+# Compare the values.
+MATCH=0
+while read line; do
+ if echo $line | grep -q "foo_timer_fn:"; then
+ NAME=`echo $line | sed 's/.*name=\([^ ]*\) .*/\1/'`
+ COUNT=`echo $line | sed 's/.*count=\([^ ]*\).*/\1/'`
+ if grep -q "myevent:.*name=\"${NAME}\" count=$COUNT" trace; then
+ MATCH=$((MATCH+1))
+ fi
+ fi
+done < trace
+
+if [ $MATCH -eq 0 ]; then
+ echo "No matching events found"
+ exit_fail
+fi
+
+# Clean up
+echo 0 > events/mysample/myevent/enable
+echo 0 > events/sample-trace/foo_timer_fn/enable
+echo > dynamic_events
+clear_trace
diff --git a/tools/testing/selftests/ftrace/test.d/dynevent/fprobe_syntax_errors.tc b/tools/testing/selftests/ftrace/test.d/dynevent/fprobe_syntax_errors.tc
index fee479295e2f..b781ec07c0d0 100644
--- a/tools/testing/selftests/ftrace/test.d/dynevent/fprobe_syntax_errors.tc
+++ b/tools/testing/selftests/ftrace/test.d/dynevent/fprobe_syntax_errors.tc
@@ -112,6 +112,15 @@ check_error 'f vfs_read%return $retval->^foo' # NO_PTR_STRCT
check_error 'f vfs_read file->^foo' # NO_BTF_FIELD
check_error 'f vfs_read file^-.foo' # BAD_HYPHEN
check_error 'f vfs_read ^file:string' # BAD_TYPE4STR
+if grep -qF "[(structname" README ; then
+check_error 'f vfs_read arg1=(task_struct)file^' # TYPECAST_REQ_FIELD
+check_error 'f vfs_read arg1=(f)((f)((f)((f)^((f)file->f)->f)->f)->f)->f' # TOO_MANY_NESTED
+check_error 'f vfs_read arg1=(task_struct,^in_execve)file->comm' # TYPECAST_NOT_ALIGNED
+check_error 'f vfs_read arg1=(task_struct,se^->group_node)file->comm' # TYPECAST_BAD_ARROW
+check_error 'f vfs_read arg1=(task_struct,^->pid)file->comm' # TYPECAST_BAD_ARROW
+check_error 'f vfs_read arg1=(task_struct,^.pid)file->comm' # BTF_BAD_TID
+check_error 'f vfs_read arg1=(task_struct,^.)file->comm' # BTF_BAD_TID
+fi
fi
else
diff --git a/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_syntax_errors.tc b/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_syntax_errors.tc
index 8f1c58f0c239..78f015c8c010 100644
--- a/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_syntax_errors.tc
+++ b/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_syntax_errors.tc
@@ -115,6 +115,15 @@ check_error 'p vfs_read+20 ^$arg*' # NOFENTRY_ARGS
check_error 'p vfs_read ^hoge' # NO_BTFARG
check_error 'p kfree ^$arg10' # NO_BTFARG (exceed the number of parameters)
check_error 'r kfree ^$retval' # NO_RETVAL
+if grep -qF "[(structname" README ; then
+check_error 'p vfs_read arg1=(task_struct)file^' # TYPECAST_REQ_FIELD
+check_error 'p vfs_read arg1=(f)((f)((f)((f)^((f)file->f)->f)->f)->f)->f' # TOO_MANY_NESTED
+check_error 'p vfs_read arg1=(task_struct,^in_execve)file->comm' # TYPECAST_NOT_ALIGNED
+check_error 'p vfs_read arg1=(task_struct,se^->group_node)file->comm' # TYPECAST_BAD_ARROW
+check_error 'p vfs_read arg1=(task_struct,^->pid)file->comm' # TYPECAST_BAD_ARROW
+check_error 'p vfs_read arg1=(task_struct,^.pid)file->comm' # BTF_BAD_TID
+check_error 'p vfs_read arg1=(task_struct,^.)file->comm' # BTF_BAD_TID
+fi
else
check_error 'p vfs_read ^$arg*' # NOSUP_BTFARG
fi
diff --git a/tools/testing/selftests/ftrace/test.d/kprobe/uprobe_syntax_errors.tc b/tools/testing/selftests/ftrace/test.d/kprobe/uprobe_syntax_errors.tc
index c817158b99db..d5d5245bee6c 100644
--- a/tools/testing/selftests/ftrace/test.d/kprobe/uprobe_syntax_errors.tc
+++ b/tools/testing/selftests/ftrace/test.d/kprobe/uprobe_syntax_errors.tc
@@ -28,4 +28,9 @@ if grep -q ".*symstr.*" README; then
check_error 'p /bin/sh:10 $stack0:^symstr' # BAD_TYPE
fi
+# $current is not supported by uprobe
+if grep -q "\$current.*" README; then
+check_error 'p /bin/sh:10 $current:^u8' # BAD_VAR
+fi
+
exit 0
^ permalink raw reply related
* Re: [PATCH] docs: kbuild: remove ISDN references in Makefile examples
From: Julian Braha @ 2026-06-14 15:00 UTC (permalink / raw)
To: Ethan Nelson-Moore, Shuah Khan, Chen Pei, Randy Dunlap,
Jonathan Corbet, linux-kbuild, linux-doc
Cc: Nathan Chancellor, Nicolas Schier, Andrew Jones
In-Reply-To: <20260613232830.147116-1-enelsonmoore@gmail.com>
On 6/14/26 00:28, Ethan Nelson-Moore wrote:
> Documentation/kbuild/makefiles.rst uses some extracts from now-removed
> ISDN code as examples. While they are harmless, they appeared in my
> checks for CONFIG_* symbols referenced but not defined in the kernel.
Hi Ethan, are you using the kconfig-sym-check[1] that was recently
merged? This dead symbol check should not have the false positives on
documentation.
Though maybe your check also catches dead symbols in C, Rust, Makefiles?
[1]
https://lore.kernel.org/all/20260527142703.107110-1-andrew.jones@linux.dev/
- Julian Braha
^ permalink raw reply
* [PATCH 0/3] mm/zram: route block swap I/O through swap_ops
From: Jianyue Wu @ 2026-06-14 15:35 UTC (permalink / raw)
To: Andrew Morton
Cc: Christoph Hellwig, Chris Li, Baoquan He, Nhat Pham, Barry Song,
Kairui Song, Kemeng Shi, Youngjun Park, Minchan Kim,
Sergey Senozhatsky, Jens Axboe, Matthew Wilcox (Oracle), Jan Kara,
linux-mm, linux-kernel, linux-block, linux-doc, Jianyue Wu
This series builds on Christoph Hellwig's swap batching rework that
moves block swap onto struct swap_iocb and per-backend struct
swap_ops handlers [1]. Christoph's patches unify batching for
ordinary block devices and swap files. zram still needs a custom
path because swap slots map to compressed pages, not disk sectors.
The first patch adds swap_register_block_ops() so a block driver can
install custom submit_read/submit_write handlers when swapon targets
its block device. The default swap_bdev_ops path is unchanged for
devices that do not register.
The second patch registers zram_swap_ops at module init. On write,
the swap core still batches folios into a swap_iocb. zram maps each
folio to a slot index and stores it through zram_write_page() instead
of building one bio per page. Read handling keeps slot_lock and
mark_slot_accessed() in one critical section. Writeback-enabled zram
falls back to swap_bdev_submit_read() for ZRAM_WB slots.
The third patch moves slot_free_notify into swap_ops next to the
other zram swap callbacks, and documents the locking contract for
that hook.
Applied on top of Christoph Hellwig's "better block swap batching and
a different take on swap_ops" series [1].
[1] https://lore.kernel.org/linux-mm/?q=better+block+swap+batching
To: Andrew Morton <akpm@linux-foundation.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Chris Li <chrisl@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Kairui Song <kasong@tencent.com>
Cc: Kemeng Shi <shikemeng@huaweicloud.com>
Cc: Youngjun Park <youngjun.park@lge.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Jan Kara <jack@suse.cz>
Cc: linux-mm@kvack.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-block@vger.kernel.org
Cc: linux-doc@vger.kernel.org
Signed-off-by: Jianyue Wu <wujianyue000@gmail.com>
---
Jianyue Wu (3):
mm/page_io: let block drivers register custom swap I/O ops
mm/zram: handle swap read/write via swap_ops
mm/swap: route slot free notifications through swap_ops
Documentation/filesystems/locking.rst | 5 -
drivers/block/zram/zram_drv.c | 215 +++++++++++++++++++++++++++-------
include/linux/blkdev.h | 2 -
include/linux/swap.h | 47 ++++++++
mm/page_io.c | 187 ++++++++++++++++++++++++++++-
mm/swap.h | 18 +--
mm/swapfile.c | 17 +--
rust/kernel/block/mq/gen_disk.rs | 1 -
8 files changed, 414 insertions(+), 78 deletions(-)
---
base-commit: 842f51deada6449843f811bfa22e536a01ae5a0c
change-id: 20260614-zram-swap-ops-block-register-a1b2c3d4e5f6
Best regards,
--
Jianyue Wu <wujianyue000@gmail.com>
^ permalink raw reply
* [PATCH 1/3] mm/page_io: let block drivers register custom swap I/O ops
From: Jianyue Wu @ 2026-06-14 15:35 UTC (permalink / raw)
To: Andrew Morton
Cc: Christoph Hellwig, Chris Li, Baoquan He, Nhat Pham, Barry Song,
Kairui Song, Kemeng Shi, Youngjun Park, Minchan Kim,
Sergey Senozhatsky, Jens Axboe, Matthew Wilcox (Oracle), Jan Kara,
linux-mm, linux-kernel, linux-block, linux-doc, Jianyue Wu
In-Reply-To: <20260614-zram-swap-ops-block-register-v1-0-6c1a6639c222@gmail.com>
Add swap_register_block_ops() so a block driver can install custom
swap read/write handlers instead of always building bios.
When swapon targets a block device (S_ISBLK), setup_swap_extents()
checks whether that driver's block_device_operations were registered.
If yes, sis->ops points at the driver table. Otherwise sis->ops
stays on swap_bdev_ops.
Swap files are unchanged. They still use the filesystem path and
extent tree, because their page index is not a raw disk sector.
Register swap_ops in a single global slot keyed by the driver's
block_device_operations. lookup_swap_block_ops() matches sis->bdev
fops at swapon. -EBUSY if the slot is already taken. That is enough
while only zram needs custom swap I/O. Several block drivers would
need a per-fops lookup table instead.
swap_unregister_block_ops() must pass the same fops that
registered. Swap areas created before unregister keep the old ops
until swapoff. The driver module must remain loaded while they are
in use.
Signed-off-by: Jianyue Wu <wujianyue000@gmail.com>
---
include/linux/swap.h | 35 +++++++++++++++++
mm/page_io.c | 106 +++++++++++++++++++++++++++++++++++++++++++++++++++
mm/swap.h | 18 +--------
mm/swapfile.c | 4 ++
4 files changed, 147 insertions(+), 16 deletions(-)
diff --git a/include/linux/swap.h b/include/linux/swap.h
index 636d94108166..1d51df4179c1 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -19,6 +19,41 @@
struct notifier_block;
struct bio;
+struct block_device_operations;
+struct folio;
+struct swap_iocb;
+struct swap_info_struct;
+
+struct swap_io_ctx {
+ struct swap_iocb *sio;
+ struct swap_info_struct *sis;
+};
+
+/* Set when the swap backend requires GFP_NOFS allocations. */
+#define SWAP_OPS_F_NOFS (1U << 0)
+
+/**
+ * struct swap_ops - per-swap-area I/O batching callbacks
+ * @can_merge: optional. Return true iff @folio can be appended to a ctx
+ * that already holds @prev_folio of @prev_folio_size bytes.
+ * When NULL, folios on the same swap area are batched until
+ * the iocb is full or the plug is flushed.
+ * @submit_write: flush the accumulated write ctx to the backend.
+ * @submit_read: flush the accumulated read ctx to the backend.
+ */
+struct swap_ops {
+ unsigned int flags;
+
+ bool (*can_merge)(struct folio *folio,
+ struct folio *prev_folio,
+ size_t prev_folio_size, int rw);
+ void (*submit_write)(struct swap_io_ctx *ctx);
+ void (*submit_read)(struct swap_io_ctx *ctx);
+};
+
+int swap_register_block_ops(const struct block_device_operations *fops,
+ const struct swap_ops *ops);
+void swap_unregister_block_ops(const struct block_device_operations *fops);
#define SWAP_FLAG_PREFER 0x8000 /* set if swap priority specified */
#define SWAP_FLAG_PRIO_MASK 0x7fff
diff --git a/mm/page_io.c b/mm/page_io.c
index c020e8ebf966..3ab620860379 100644
--- a/mm/page_io.c
+++ b/mm/page_io.c
@@ -24,6 +24,8 @@
#include <linux/uio.h>
#include <linux/sched/task.h>
#include <linux/delayacct.h>
+#include <linux/export.h>
+#include <linux/mutex.h>
#include <linux/zswap.h>
#include "swap.h"
#include "swap_table.h"
@@ -325,6 +327,8 @@ static bool swap_can_merge(struct swap_io_ctx *ctx, struct folio *folio,
if (ctx->sis != sis)
return false;
+ if (!sis->ops->can_merge)
+ return true;
return sis->ops->can_merge(folio, prev_folio, prev_folio_size, rw);
}
@@ -577,6 +581,18 @@ static void swap_bio_read_end_io(struct bio *bio)
swap_read_end(sio, failed);
}
+/**
+ * swap_bdev_submit_write - default block-device write path for swap
+ * @ctx: in-progress submit_write context.
+ *
+ * Builds a bio for the accumulated ctx and submits it through the normal
+ * block layer. This is the submit_write implementation used by swap_bdev_ops
+ * for ordinary block swap areas. swap_ops providers that override submit_write
+ * (e.g. zram) but still fall back to the block layer for some I/Os should use
+ * their own bio construction, this function is not exported.
+ *
+ * Context: process context (may sleep if SWP_SYNCHRONOUS_IO is set).
+ */
static void swap_bdev_submit_write(struct swap_io_ctx *ctx)
{
struct swap_iocb *sio = ctx->sio;
@@ -640,6 +656,96 @@ const struct swap_ops swap_bdev_ops = {
.can_merge = swap_bdev_can_merge,
};
+static DEFINE_MUTEX(swap_block_ops_lock);
+static const struct block_device_operations *swap_block_fops;
+static const struct swap_ops *swap_block_ops;
+
+/**
+ * swap_register_block_ops - install swap callbacks for a block driver
+ * @fops: block_device_operations identifying the driver. Used as a
+ * match key in setup_swap_extents(): a S_ISBLK swap area is
+ * routed to @ops when its bdev's gendisk fops equals @fops.
+ * @ops: swap_ops vtable selected for matching swap areas. Must populate
+ * ->submit_read and ->submit_write. ->can_merge is optional.
+ *
+ * Lets a block driver (zram and similar) replace the default
+ * swap_bdev_ops with its own submit_read / submit_write implementation.
+ *
+ * Returns 0 on success, -EINVAL when @fops or @ops are bad (a required
+ * callback is missing), or -EBUSY when the single registration slot is
+ * already taken. That slot is enough while only zram needs custom swap I/O.
+ * Several block drivers would need a per-fops lookup table instead.
+ *
+ * Context: process context, may sleep.
+ */
+int swap_register_block_ops(const struct block_device_operations *fops,
+ const struct swap_ops *ops)
+{
+ int ret;
+
+ if (WARN_ON_ONCE(!fops || !ops || !ops->submit_read ||
+ !ops->submit_write))
+ return -EINVAL;
+
+ mutex_lock(&swap_block_ops_lock);
+ if (swap_block_fops || swap_block_ops) {
+ ret = -EBUSY;
+ goto out;
+ }
+ swap_block_fops = fops;
+ swap_block_ops = ops;
+ ret = 0;
+out:
+ mutex_unlock(&swap_block_ops_lock);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(swap_register_block_ops);
+
+/**
+ * swap_unregister_block_ops - undo swap_register_block_ops()
+ * @fops: same block_device_operations passed to swap_register_block_ops().
+ *
+ * Clears the registered fops/ops slot so future swapon calls fall back
+ * to swap_bdev_ops. The @fops match acts as a soft owner check so a
+ * driver cannot accidentally tear down another driver's registration.
+ * A mismatch is treated as a bug and triggers WARN_ON_ONCE. Swap areas
+ * that already captured the registered ops keep their sis->ops pointer.
+ * The caller must ensure the module owning the ops outlives any such
+ * swap area. For block drivers this is guaranteed by the bdev open
+ * reference held across swapon.
+ * Calling unregister before a successful register is a no-op.
+ *
+ * Context: process context, may sleep.
+ */
+void swap_unregister_block_ops(const struct block_device_operations *fops)
+{
+ mutex_lock(&swap_block_ops_lock);
+ /* never registered or already unregistered. */
+ if (!swap_block_fops)
+ goto out;
+ if (WARN_ON_ONCE(swap_block_fops != fops))
+ goto out;
+ swap_block_fops = NULL;
+ swap_block_ops = NULL;
+out:
+ mutex_unlock(&swap_block_ops_lock);
+}
+EXPORT_SYMBOL_GPL(swap_unregister_block_ops);
+
+const struct swap_ops *lookup_swap_block_ops(struct swap_info_struct *sis)
+{
+ const struct swap_ops *ops = NULL;
+
+ if (!sis->bdev)
+ return NULL;
+
+ mutex_lock(&swap_block_ops_lock);
+ if (swap_block_fops && sis->bdev->bd_disk->fops == swap_block_fops)
+ ops = swap_block_ops;
+ mutex_unlock(&swap_block_ops_lock);
+ return ops;
+}
+
static void swap_fs_submit(struct swap_io_ctx *ctx, int rw)
{
struct swap_iocb *sio = ctx->sio;
diff --git a/mm/swap.h b/mm/swap.h
index edb512e619ee..4bdd38f7a5e8 100644
--- a/mm/swap.h
+++ b/mm/swap.h
@@ -4,6 +4,7 @@
#include <linux/atomic.h> /* for atomic_long_t */
#include <linux/mm.h> /* for PAGE_SHIFT */
+#include <linux/swap.h>
struct mempolicy;
struct swap_iocb;
@@ -79,22 +80,6 @@ enum swap_cluster_flags {
CLUSTER_FLAG_MAX,
};
-struct swap_io_ctx {
- struct swap_iocb *sio;
- struct swap_info_struct *sis;
-};
-
-#define SWAP_OPS_F_NOFS (1U << 0)
-
-struct swap_ops {
- unsigned int flags;
-
- bool (*can_merge)(struct folio *folio, struct folio *prev_folio,
- size_t prev_folio_size, int rw);
- void (*submit_write)(struct swap_io_ctx *ctx);
- void (*submit_read)(struct swap_io_ctx *ctx);
-};
-
#ifdef CONFIG_SWAP
#include <linux/swapops.h> /* for swp_offset */
#include <linux/blk_types.h> /* for bio_end_io_t */
@@ -472,6 +457,7 @@ static inline void __swap_cache_replace_folio(struct swap_cluster_info *ci,
#endif /* CONFIG_SWAP */
extern const struct swap_ops swap_bdev_ops;
+const struct swap_ops *lookup_swap_block_ops(struct swap_info_struct *sis);
int shmem_writeout(struct swap_io_ctx *ctx, struct folio *folio,
struct list_head *folio_list);
diff --git a/mm/swapfile.c b/mm/swapfile.c
index 284eebc40a70..ebdc96092961 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -2849,6 +2849,10 @@ static int setup_swap_extents(struct swap_info_struct *sis,
sis->ops = &swap_bdev_ops;
if (S_ISBLK(inode->i_mode)) {
+ const struct swap_ops *block_ops = lookup_swap_block_ops(sis);
+
+ if (block_ops)
+ sis->ops = block_ops;
ret = add_swap_extent(sis, 0, sis->max, 0);
*span = sis->pages;
return ret;
--
2.43.0
^ permalink raw reply related
* [PATCH 2/3] mm/zram: handle swap read/write via swap_ops
From: Jianyue Wu @ 2026-06-14 15:35 UTC (permalink / raw)
To: Andrew Morton
Cc: Christoph Hellwig, Chris Li, Baoquan He, Nhat Pham, Barry Song,
Kairui Song, Kemeng Shi, Youngjun Park, Minchan Kim,
Sergey Senozhatsky, Jens Axboe, Matthew Wilcox (Oracle), Jan Kara,
linux-mm, linux-kernel, linux-block, linux-doc, Jianyue Wu
In-Reply-To: <20260614-zram-swap-ops-block-register-v1-0-6c1a6639c222@gmail.com>
Register zram_swap_ops at module init. The swap core still batches
folios into a swap_iocb; on flush, zram_swap_submit_write() maps each
folio page to its swap slot index and stores it via zram_write_page()
into the zspool, avoiding one bio per page.
For swap-in, zram_swap_submit_read() walks the same batch. Without a
backing device, each slot is decompressed with read_from_zspool() while
slot_lock is held and mark_slot_accessed() runs in the same critical
section, so idle writeback cannot take the slot between read and mark.
When backing_dev is set, delegate the entire iocb to
swap_bdev_submit_read() because the batch may mix ZRAM_WB slots that
live on the backing block device.
Omit ->can_merge: zram batches through swap_iocb and compresses each
slot by index. Block-sector merge rules do not apply.
Export swap_iocb_nr_folios(), swap_iocb_folio(), swap_read_end(),
swap_write_end(), and swap_bdev_submit_read() for the custom swap I/O
path.
Fail zram_init() if swap_register_block_ops() fails so the module
does not load without its swap path registered.
Signed-off-by: Jianyue Wu <wujianyue000@gmail.com>
---
drivers/block/zram/zram_drv.c | 127 ++++++++++++++++++++++++++++++++++++++++++
include/linux/swap.h | 5 ++
mm/page_io.c | 81 ++++++++++++++++++++++++++-
3 files changed, 210 insertions(+), 3 deletions(-)
diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index 7917fc7a2a29..9b2bd0287402 100644
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -34,6 +34,8 @@
#include <linux/part_stat.h>
#include <linux/kernel_read_file.h>
#include <linux/rcupdate.h>
+#include <linux/swap.h>
+#include <linux/swapops.h>
#include "zram_drv.h"
@@ -55,6 +57,9 @@ static unsigned int num_devices = 1;
static size_t huge_class_size;
static const struct block_device_operations zram_devops;
+#if IS_ENABLED(CONFIG_SWAP)
+static bool zram_swap_ops_registered;
+#endif
static void slot_free(struct zram *zram, u32 index);
#define slot_dep_map(zram, index) (&(zram)->table[(index)].dep_map)
@@ -2958,6 +2963,115 @@ static int zram_open(struct gendisk *disk, blk_mode_t mode)
return 0;
}
+#if IS_ENABLED(CONFIG_SWAP)
+static void zram_swap_submit_read(struct swap_io_ctx *ctx)
+{
+ struct zram *zram = ctx->sis->bdev->bd_disk->private_data;
+ struct swap_iocb *sio = ctx->sio;
+ int nr = swap_iocb_nr_folios(sio);
+ bool failed = false;
+ int i, j;
+
+ /*
+ * With a backing device configured, the batch may include ZRAM_WB
+ * slots. Fall back to the block read path for the whole iocb
+ * instead of checking each slot.
+ */
+#ifdef CONFIG_ZRAM_WRITEBACK
+ if (zram->backing_dev) {
+ swap_bdev_submit_read(ctx);
+ return;
+ }
+#endif
+
+ for (i = 0; i < nr; i++) {
+ struct folio *folio = swap_iocb_folio(sio, i);
+ u32 base = swp_offset(folio->swap);
+
+ for (j = 0; j < folio_nr_pages(folio); j++) {
+ u32 idx = base + j;
+ struct page *page = folio_page(folio, j);
+ int ret;
+
+ /*
+ * read_from_zspool() and mark_slot_accessed() must run
+ * under the same slot_lock. zram_read_page() unlocks
+ * before returning, which leaves a window where
+ * writeback can pick an idle slot we just read.
+ */
+ slot_lock(zram, idx);
+ ret = read_from_zspool(zram, page, idx);
+ if (!ret)
+ mark_slot_accessed(zram, idx);
+ slot_unlock(zram, idx);
+ if (ret) {
+ failed = true;
+ atomic64_inc(&zram->stats.failed_reads);
+ pr_alert_ratelimited("Read-error on swap-device %s at index %u: err=%d\n",
+ zram->disk->disk_name, idx, ret);
+ goto out;
+ }
+ flush_dcache_page(page);
+ }
+ }
+out:
+ swap_read_end(sio, failed);
+}
+
+static void zram_swap_submit_write(struct swap_io_ctx *ctx)
+{
+ struct zram *zram = ctx->sis->bdev->bd_disk->private_data;
+ struct swap_iocb *sio = ctx->sio;
+ int nr = swap_iocb_nr_folios(sio);
+ bool failed = false;
+ int i, j, ret = 0;
+ u32 idx = 0;
+
+ for (i = 0; i < nr; i++) {
+ struct folio *folio = swap_iocb_folio(sio, i);
+ u32 base = swp_offset(folio->swap);
+
+ for (j = 0; j < folio_nr_pages(folio); j++) {
+ idx = base + j;
+ ret = zram_write_page(zram, folio_page(folio, j), idx);
+ if (ret) {
+ /*
+ * Leave partial zram data in place, same as the bio
+ * write path. swap_write_end() re-dirties every
+ * page in the batch so they stay in swapcache with
+ * their swap entries. Freeing zram slots here would
+ * leave entries pointing at empty indices until
+ * slot_free_notify runs.
+ */
+ failed = true;
+ atomic64_inc(&zram->stats.failed_writes);
+ pr_alert_ratelimited("Write-error on swap-device %s at index %u: err=%d\n",
+ zram->disk->disk_name, idx, ret);
+ goto out;
+ }
+ slot_lock(zram, idx);
+ mark_slot_accessed(zram, idx);
+ slot_unlock(zram, idx);
+ }
+ }
+out:
+ swap_write_end(sio, failed);
+}
+
+/*
+ * No ->can_merge: block rules exist to grow bios on contiguous sectors and
+ * matching blkcg. zram already batches through swap_iocb, and
+ * submit_write() compresses each slot by index, not by sector layout.
+ * Reusing swap_bdev_can_merge() would only split batches without helping
+ * zspool I/O.
+ */
+static const struct swap_ops zram_swap_ops = {
+ .submit_read = zram_swap_submit_read,
+ .submit_write = zram_swap_submit_write,
+};
+
+#endif /* CONFIG_SWAP */
+
static const struct block_device_operations zram_devops = {
.open = zram_open,
.submit_bio = zram_submit_bio,
@@ -3233,6 +3347,10 @@ static int zram_remove_cb(int id, void *ptr, void *data)
static void destroy_devices(void)
{
+#if IS_ENABLED(CONFIG_SWAP)
+ if (zram_swap_ops_registered)
+ swap_unregister_block_ops(&zram_devops);
+#endif
class_unregister(&zram_control_class);
idr_for_each(&zram_index_idr, &zram_remove_cb, NULL);
zram_debugfs_destroy();
@@ -3269,6 +3387,15 @@ static int __init zram_init(void)
return -EBUSY;
}
+#if IS_ENABLED(CONFIG_SWAP)
+ ret = swap_register_block_ops(&zram_devops, &zram_swap_ops);
+ if (ret) {
+ pr_err("zram: failed to register swap ops (%d)\n", ret);
+ goto out_error;
+ }
+ zram_swap_ops_registered = true;
+#endif
+
while (num_devices != 0) {
mutex_lock(&zram_index_mutex);
ret = zram_add();
diff --git a/include/linux/swap.h b/include/linux/swap.h
index 1d51df4179c1..70bf6f3f04dc 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -54,6 +54,11 @@ struct swap_ops {
int swap_register_block_ops(const struct block_device_operations *fops,
const struct swap_ops *ops);
void swap_unregister_block_ops(const struct block_device_operations *fops);
+int swap_iocb_nr_folios(struct swap_iocb *sio);
+struct folio *swap_iocb_folio(struct swap_iocb *sio, int idx);
+void swap_read_end(struct swap_iocb *sio, bool failed);
+void swap_write_end(struct swap_iocb *sio, bool failed);
+void swap_bdev_submit_read(struct swap_io_ctx *ctx);
#define SWAP_FLAG_PREFER 0x8000 /* set if swap priority specified */
#define SWAP_FLAG_PRIO_MASK 0x7fff
diff --git a/mm/page_io.c b/mm/page_io.c
index 3ab620860379..7c17e44823d1 100644
--- a/mm/page_io.c
+++ b/mm/page_io.c
@@ -486,7 +486,21 @@ void swap_read_folio(struct swap_io_ctx *ctx, struct folio *folio)
delayacct_swapin_end();
}
-static void swap_write_end(struct swap_iocb *sio, bool failed)
+/**
+ * swap_write_end - finish a swap write iocb
+ * @sio: swap_iocb whose pages were just written
+ * @failed: true if any of the underlying writes failed
+ *
+ * Ends writeback on every page captured by @sio. On failure each page
+ * is also re-dirtied and PG_reclaim is cleared, mirroring the bio
+ * write completion path. @sio is returned to the swap iocb mempool.
+ *
+ * swap_ops providers must call this exactly once per submit_write()
+ * ctx (typically at the end of their submit_write callback).
+ *
+ * Context: any context the submit_write() callback runs in.
+ */
+void swap_write_end(struct swap_iocb *sio, bool failed)
{
int p;
@@ -501,6 +515,7 @@ static void swap_write_end(struct swap_iocb *sio, bool failed)
}
mempool_free(sio, sio_pool);
}
+EXPORT_SYMBOL_GPL(swap_write_end);
static void swap_fs_write_complete(struct kiocb *iocb, long ret)
{
@@ -536,7 +551,26 @@ static void end_swap_bio_write(struct bio *bio)
swap_write_end(sio, failed);
}
-static void swap_read_end(struct swap_iocb *sio, bool failed)
+/**
+ * swap_read_end - finish a swap read iocb
+ * @sio: swap_iocb whose folios were just read in
+ * @failed: true if any of the underlying reads failed
+ *
+ * Unlocks every folio captured by @sio. On success each folio is also
+ * marked uptodate and swap-in counters (PSWPIN, mTHP, memcg) are bumped
+ * by folio_nr_pages(). On failure folios are left not-uptodate so the
+ * caller observes the failure and retries or surfaces an error. @sio is
+ * returned to the swap iocb mempool.
+ *
+ * swap_ops providers must call this exactly once per submit_read() ctx
+ * (typically at the end of their submit_read callback). If the provider
+ * defers to swap_bdev_ops.submit_read() for fallback, the bdev path
+ * will call swap_read_end() itself and the provider must not call it
+ * again for the same ctx.
+ *
+ * Context: any context the submit_read() callback runs in.
+ */
+void swap_read_end(struct swap_iocb *sio, bool failed)
{
int p;
@@ -557,6 +591,34 @@ static void swap_read_end(struct swap_iocb *sio, bool failed)
mempool_free(sio, sio_pool);
}
+EXPORT_SYMBOL_GPL(swap_read_end);
+
+/**
+ * swap_iocb_nr_folios - number of folios in a swap I/O batch
+ * @sio: swap_iocb passed to a swap_ops submit callback.
+ *
+ * Returns how many folios the swap core has batched into @sio. Used
+ * together with swap_iocb_folio() so swap_ops providers can walk the
+ * batch without depending on the swap core's internal iocb layout.
+ */
+int swap_iocb_nr_folios(struct swap_iocb *sio)
+{
+ return sio->nr_bvecs;
+}
+EXPORT_SYMBOL_GPL(swap_iocb_nr_folios);
+
+/**
+ * swap_iocb_folio - folio at slot @idx in a swap I/O batch
+ * @sio: swap_iocb passed to a swap_ops submit callback.
+ * @idx: index in the range [0, swap_iocb_nr_folios(@sio)).
+ *
+ * Returns the folio at the given batch slot.
+ */
+struct folio *swap_iocb_folio(struct swap_iocb *sio, int idx)
+{
+ return page_folio(sio->bvecs[idx].bv_page);
+}
+EXPORT_SYMBOL_GPL(swap_iocb_folio);
static void swap_fs_read_complete(struct kiocb *iocb, long ret)
{
@@ -613,7 +675,19 @@ static void swap_bdev_submit_write(struct swap_io_ctx *ctx)
}
}
-static void swap_bdev_submit_read(struct swap_io_ctx *ctx)
+/**
+ * swap_bdev_submit_read - fall back to the default block-device read path
+ * @ctx: in-progress submit_read context.
+ *
+ * Builds a bio for the accumulated ctx and submits it through the
+ * normal block layer. swap_ops providers can call this when they
+ * cannot serve a particular ctx themselves (for example zram folios
+ * stored on a backing device). The bio completion path takes care of
+ * calling swap_read_end() on @ctx. The caller must not call it again.
+ *
+ * Context: any context the submit_read() callback runs in.
+ */
+void swap_bdev_submit_read(struct swap_io_ctx *ctx)
{
struct swap_iocb *sio = ctx->sio;
struct bio *bio = &sio->bio;
@@ -638,6 +712,7 @@ static void swap_bdev_submit_read(struct swap_io_ctx *ctx)
submit_bio(bio);
}
}
+EXPORT_SYMBOL_GPL(swap_bdev_submit_read);
static bool swap_bdev_can_merge(struct folio *folio, struct folio *prev_folio,
size_t prev_folio_size, int rw)
--
2.43.0
^ permalink raw reply related
* [PATCH 3/3] mm/swap: route slot free notifications through swap_ops
From: Jianyue Wu @ 2026-06-14 15:35 UTC (permalink / raw)
To: Andrew Morton
Cc: Christoph Hellwig, Chris Li, Baoquan He, Nhat Pham, Barry Song,
Kairui Song, Kemeng Shi, Youngjun Park, Minchan Kim,
Sergey Senozhatsky, Jens Axboe, Matthew Wilcox (Oracle), Jan Kara,
linux-mm, linux-kernel, linux-block, linux-doc, Jianyue Wu
In-Reply-To: <20260614-zram-swap-ops-block-register-v1-0-6c1a6639c222@gmail.com>
Dispatch slot_free_notify through swap_ops instead of
block_device_operations. Zram keeps slot-free handling alongside its
other swap_ops methods.
Move slot_trylock into the CONFIG_SWAP block. With CONFIG_SWAP=n it
has no callers and the build fails on -Werror=unused-function.
Document the callback locking rules in include/linux/swap.h. Remove
the outdated locking.rst note for swap_slot_free_notify.
Signed-off-by: Jianyue Wu <wujianyue000@gmail.com>
---
Documentation/filesystems/locking.rst | 5 --
drivers/block/zram/zram_drv.c | 88 ++++++++++++++++++-----------------
include/linux/blkdev.h | 2 -
include/linux/swap.h | 7 +++
mm/swapfile.c | 13 ++----
rust/kernel/block/mq/gen_disk.rs | 1 -
6 files changed, 57 insertions(+), 59 deletions(-)
diff --git a/Documentation/filesystems/locking.rst b/Documentation/filesystems/locking.rst
index 70481bdc031d..964c841bf917 100644
--- a/Documentation/filesystems/locking.rst
+++ b/Documentation/filesystems/locking.rst
@@ -443,7 +443,6 @@ prototypes::
unsigned long *);
void (*unlock_native_capacity) (struct gendisk *);
int (*getgeo)(struct gendisk *, struct hd_geometry *);
- void (*swap_slot_free_notify) (struct block_device *, unsigned long);
locking rules:
@@ -457,12 +456,8 @@ compat_ioctl: no
direct_access: no
unlock_native_capacity: no
getgeo: no
-swap_slot_free_notify: no (see below)
======================= ===================
-swap_slot_free_notify is called with swap_lock and sometimes the page lock
-held.
-
file_operations
===============
diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index 9b2bd0287402..b78246dc1746 100644
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -72,31 +72,6 @@ static void slot_lock_init(struct zram *zram, u32 index)
&__key, 0);
}
-/*
- * entry locking rules:
- *
- * 1) Lock is exclusive
- *
- * 2) lock() function can sleep waiting for the lock
- *
- * 3) Lock owner can sleep
- *
- * 4) Use TRY lock variant when in atomic context
- * - must check return value and handle locking failers
- */
-static __must_check bool slot_trylock(struct zram *zram, u32 index)
-{
- unsigned long *lock = &zram->table[index].__lock;
-
- if (!test_and_set_bit_lock(ZRAM_ENTRY_LOCK, lock)) {
- mutex_acquire(slot_dep_map(zram, index), 0, 1, _RET_IP_);
- lock_acquired(slot_dep_map(zram, index), _RET_IP_);
- return true;
- }
-
- return false;
-}
-
static void slot_lock(struct zram *zram, u32 index)
{
unsigned long *lock = &zram->table[index].__lock;
@@ -2798,23 +2773,6 @@ static void zram_submit_bio(struct bio *bio)
}
}
-static void zram_slot_free_notify(struct block_device *bdev,
- unsigned long index)
-{
- struct zram *zram;
-
- zram = bdev->bd_disk->private_data;
-
- atomic64_inc(&zram->stats.notify_free);
- if (!slot_trylock(zram, index)) {
- atomic64_inc(&zram->stats.miss_free);
- return;
- }
-
- slot_free(zram, index);
- slot_unlock(zram, index);
-}
-
static void zram_comp_params_reset(struct zram *zram)
{
u32 prio;
@@ -3058,6 +3016,50 @@ static void zram_swap_submit_write(struct swap_io_ctx *ctx)
swap_write_end(sio, failed);
}
+/*
+ * entry locking rules:
+ *
+ * 1) Lock is exclusive
+ *
+ * 2) lock() function can sleep waiting for the lock
+ *
+ * 3) Lock owner can sleep
+ *
+ * 4) Use TRY lock variant when in atomic context
+ * - must check return value and handle locking failers
+ */
+static __must_check bool slot_trylock(struct zram *zram, u32 index)
+{
+ unsigned long *lock = &zram->table[index].__lock;
+
+ if (!test_and_set_bit_lock(ZRAM_ENTRY_LOCK, lock)) {
+ mutex_acquire(slot_dep_map(zram, index), 0, 1, _RET_IP_);
+ lock_acquired(slot_dep_map(zram, index), _RET_IP_);
+ return true;
+ }
+
+ return false;
+}
+
+/*
+ * swap_range_free() holds the swap cluster lock. Use slot_trylock() so
+ * we never block on a slot that is already locked elsewhere.
+ */
+static void zram_swap_slot_free_notify(struct swap_info_struct *sis,
+ unsigned long index)
+{
+ struct zram *zram = sis->bdev->bd_disk->private_data;
+
+ atomic64_inc(&zram->stats.notify_free);
+ if (!slot_trylock(zram, index)) {
+ atomic64_inc(&zram->stats.miss_free);
+ return;
+ }
+
+ slot_free(zram, index);
+ slot_unlock(zram, index);
+}
+
/*
* No ->can_merge: block rules exist to grow bios on contiguous sectors and
* matching blkcg. zram already batches through swap_iocb, and
@@ -3068,6 +3070,7 @@ static void zram_swap_submit_write(struct swap_io_ctx *ctx)
static const struct swap_ops zram_swap_ops = {
.submit_read = zram_swap_submit_read,
.submit_write = zram_swap_submit_write,
+ .slot_free_notify = zram_swap_slot_free_notify,
};
#endif /* CONFIG_SWAP */
@@ -3075,7 +3078,6 @@ static const struct swap_ops zram_swap_ops = {
static const struct block_device_operations zram_devops = {
.open = zram_open,
.submit_bio = zram_submit_bio,
- .swap_slot_free_notify = zram_slot_free_notify,
.owner = THIS_MODULE
};
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 890128cdea1c..f861ceed39eb 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -1669,8 +1669,6 @@ struct block_device_operations {
int (*getgeo)(struct gendisk *, struct hd_geometry *);
int (*set_read_only)(struct block_device *bdev, bool ro);
void (*free_disk)(struct gendisk *disk);
- /* this callback is with swap_lock and sometimes page table lock held */
- void (*swap_slot_free_notify) (struct block_device *, unsigned long);
int (*report_zones)(struct gendisk *, sector_t sector,
unsigned int nr_zones,
struct blk_report_zones_args *args);
diff --git a/include/linux/swap.h b/include/linux/swap.h
index 70bf6f3f04dc..09640eb5a45d 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -40,6 +40,11 @@ struct swap_io_ctx {
* the iocb is full or the plug is flushed.
* @submit_write: flush the accumulated write ctx to the backend.
* @submit_read: flush the accumulated read ctx to the backend.
+ * @slot_free_notify: optional callback invoked when a swap slot
+ * becomes free. swap_range_free() calls it with the
+ * swap cluster lock held. The folio lock may also be
+ * held on swap-cache teardown paths. Must not sleep
+ * or block.
*/
struct swap_ops {
unsigned int flags;
@@ -49,6 +54,8 @@ struct swap_ops {
size_t prev_folio_size, int rw);
void (*submit_write)(struct swap_io_ctx *ctx);
void (*submit_read)(struct swap_io_ctx *ctx);
+ void (*slot_free_notify)(struct swap_info_struct *sis,
+ unsigned long offset);
};
int swap_register_block_ops(const struct block_device_operations *fops,
diff --git a/mm/swapfile.c b/mm/swapfile.c
index ebdc96092961..79a4166fb9bf 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -1311,21 +1311,18 @@ static void swap_range_free(struct swap_info_struct *si, unsigned long offset,
unsigned int nr_entries)
{
unsigned long end = offset + nr_entries - 1;
- void (*swap_slot_free_notify)(struct block_device *, unsigned long);
+ void (*slot_free_notify)(struct swap_info_struct *sis,
+ unsigned long offset);
unsigned int i;
for (i = 0; i < nr_entries; i++)
zswap_invalidate(swp_entry(si->type, offset + i));
- if (si->flags & SWP_BLKDEV)
- swap_slot_free_notify =
- si->bdev->bd_disk->fops->swap_slot_free_notify;
- else
- swap_slot_free_notify = NULL;
+ slot_free_notify = si->ops->slot_free_notify;
while (offset <= end) {
arch_swap_invalidate_page(si->type, offset);
- if (swap_slot_free_notify)
- swap_slot_free_notify(si->bdev, offset);
+ if (slot_free_notify)
+ slot_free_notify(si, offset);
offset++;
}
diff --git a/rust/kernel/block/mq/gen_disk.rs b/rust/kernel/block/mq/gen_disk.rs
index 912cb805caf5..25552d69f711 100644
--- a/rust/kernel/block/mq/gen_disk.rs
+++ b/rust/kernel/block/mq/gen_disk.rs
@@ -135,7 +135,6 @@ pub fn build<T: Operations>(
unlock_native_capacity: None,
getgeo: None,
set_read_only: None,
- swap_slot_free_notify: None,
report_zones: None,
devnode: None,
alternative_gpt_sector: None,
--
2.43.0
^ permalink raw reply related
* [PATCH] cxl: docs/linux/dax-driver - fix typos
From: Zenghui Yu @ 2026-06-14 16:14 UTC (permalink / raw)
To: linux-cxl, linux-doc, linux-kernel
Cc: dave, jic23, dave.jiang, alison.schofield, vishal.l.verma,
ira.weiny, djbw, gourry, corbet, skhan, Zenghui Yu
Fix two obvious typos in the "kmem conversion" section.
Signed-off-by: Zenghui Yu <zenghui.yu@linux.dev>
---
Documentation/driver-api/cxl/linux/dax-driver.rst | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/Documentation/driver-api/cxl/linux/dax-driver.rst b/Documentation/driver-api/cxl/linux/dax-driver.rst
index 10d953a2167b..72c85a0f8606 100644
--- a/Documentation/driver-api/cxl/linux/dax-driver.rst
+++ b/Documentation/driver-api/cxl/linux/dax-driver.rst
@@ -35,9 +35,9 @@ will be exposed to the kernel page allocator in the user-selected memory
zone.
The :code:`memmap_on_memory` setting (both global and DAX device local)
-dictates where the kernell will allocate the :code:`struct folio` descriptors
+dictates where the kernel will allocate the :code:`struct folio` descriptors
for this memory will come from. If :code:`memmap_on_memory` is set, memory
hotplug will set aside a portion of the memory block capacity to allocate
folios. If unset, the memory is allocated via a normal :code:`GFP_KERNEL`
-allocation - and as a result will most likely land on the local NUM node of the
+allocation - and as a result will most likely land on the local NUMA node of the
CPU executing the hotplug operation.
--
2.53.0
^ permalink raw reply related
* [PATCH net-next v5 04/15] net: phy: microchip_t1s: Use generic APIs for C45 read and write
From: Selvamani Rajagopal via B4 Relay @ 2026-06-14 17:00 UTC (permalink / raw)
To: Andrew Lunn, Piergiorgio Beruto, Heiner Kallweit, Russell King,
David S. Miller, Eric Dumazet, Jakub Kicinski, Paolo Abeni,
Andrew Lunn, Parthiban Veerasooran, Selva Rajagopal,
Richard Cochran, Rob Herring, Krzysztof Kozlowski, Conor Dooley,
Simon Horman, Jonathan Corbet, Shuah Khan
Cc: netdev, linux-kernel, devicetree, linux-doc, Jerry Ray,
Selvamani Rajagopal
In-Reply-To: <20260614-s2500-mac-phy-support-v5-0-89874b72f725@onsemi.com>
From: Selvamani Rajagopal <Selvamani.Rajagopal@onsemi.com>
Replace vendor implementation with generic API to read and write
PHY registers using C45 bus protocol.
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Selvamani Rajagopal <Selvamani.Rajagopal@onsemi.com>
---
changes in v5
- no change
changes in v4
- no change
changes in v3
- Updated vendor specific phy_read_mmd/phy_write_mmd functions to
use genphy read/write APIs that is introduced
- First patch
---
drivers/net/phy/microchip_t1s.c | 32 ++------------------------------
1 file changed, 2 insertions(+), 30 deletions(-)
diff --git a/drivers/net/phy/microchip_t1s.c b/drivers/net/phy/microchip_t1s.c
index e601d56b2507..0c4dc70641d8 100644
--- a/drivers/net/phy/microchip_t1s.c
+++ b/drivers/net/phy/microchip_t1s.c
@@ -506,34 +506,6 @@ static int lan86xx_read_status(struct phy_device *phydev)
return 0;
}
-/* OPEN Alliance 10BASE-T1x compliance MAC-PHYs will have both C22 and
- * C45 registers space. If the PHY is discovered via C22 bus protocol it assumes
- * it uses C22 protocol and always uses C22 registers indirect access to access
- * C45 registers. This is because, we don't have a clean separation between
- * C22/C45 register space and C22/C45 MDIO bus protocols. Resulting, PHY C45
- * registers direct access can't be used which can save multiple SPI bus access.
- * To support this feature, set .read_mmd/.write_mmd in the PHY driver to call
- * .read_c45/.write_c45 in the OPEN Alliance framework
- * drivers/net/ethernet/oa_tc6.c
- */
-static int lan865x_phy_read_mmd(struct phy_device *phydev, int devnum,
- u16 regnum)
-{
- struct mii_bus *bus = phydev->mdio.bus;
- int addr = phydev->mdio.addr;
-
- return __mdiobus_c45_read(bus, addr, devnum, regnum);
-}
-
-static int lan865x_phy_write_mmd(struct phy_device *phydev, int devnum,
- u16 regnum, u16 val)
-{
- struct mii_bus *bus = phydev->mdio.bus;
- int addr = phydev->mdio.addr;
-
- return __mdiobus_c45_write(bus, addr, devnum, regnum, val);
-}
-
static struct phy_driver microchip_t1s_driver[] = {
{
PHY_ID_MATCH_EXACT(PHY_ID_LAN867X_REVB1),
@@ -584,8 +556,8 @@ static struct phy_driver microchip_t1s_driver[] = {
.features = PHY_BASIC_T1S_P2MP_FEATURES,
.config_init = lan865x_revb_config_init,
.read_status = lan86xx_read_status,
- .read_mmd = lan865x_phy_read_mmd,
- .write_mmd = lan865x_phy_write_mmd,
+ .read_mmd = genphy_phy_read_mmd,
+ .write_mmd = genphy_phy_write_mmd,
.get_plca_cfg = genphy_c45_plca_get_cfg,
.set_plca_cfg = lan86xx_plca_set_cfg,
.get_plca_status = genphy_c45_plca_get_status,
--
2.43.0
^ permalink raw reply related
* [PATCH net-next v5 03/15] net: ethernet: oa_tc6: Move oa_tc6.c to its own directory
From: Selvamani Rajagopal via B4 Relay @ 2026-06-14 17:00 UTC (permalink / raw)
To: Andrew Lunn, Piergiorgio Beruto, Heiner Kallweit, Russell King,
David S. Miller, Eric Dumazet, Jakub Kicinski, Paolo Abeni,
Andrew Lunn, Parthiban Veerasooran, Selva Rajagopal,
Richard Cochran, Rob Herring, Krzysztof Kozlowski, Conor Dooley,
Simon Horman, Jonathan Corbet, Shuah Khan
Cc: netdev, linux-kernel, devicetree, linux-doc, Jerry Ray,
Selvamani Rajagopal
In-Reply-To: <20260614-s2500-mac-phy-support-v5-0-89874b72f725@onsemi.com>
From: Selvamani Rajagopal <Selvamani.Rajagopal@onsemi.com>
Moving oa_tc6.c to its own directory, drivers/net/ethernet/oa_tc6. This
will facilitate adding more files to support other features
defined by OPEN Alliance 10BASE-T1x Serial Interface specification
This patch series is adding two files, one for hardware
timestamp related functions and one for PTP related APIs.
Signed-off-by: Selvamani Rajagopal <Selvamani.Rajagopal@onsemi.com>
---
changes in v5
- No change
changes in v4
- Removed reference to onsemi in Kconfig files
changes in v3
- Moved oa_tc6.c to its own, oa_tc6 directory under ethernet.
- First patch
---
MAINTAINERS | 2 +-
drivers/net/ethernet/Kconfig | 12 +-----------
drivers/net/ethernet/Makefile | 2 +-
drivers/net/ethernet/oa_tc6/Kconfig | 16 ++++++++++++++++
drivers/net/ethernet/oa_tc6/Makefile | 7 +++++++
drivers/net/ethernet/{ => oa_tc6}/oa_tc6.c | 0
6 files changed, 26 insertions(+), 13 deletions(-)
diff --git a/MAINTAINERS b/MAINTAINERS
index cc1dde0c9067..4cee98fc922c 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -20001,7 +20001,7 @@ M: Parthiban Veerasooran <parthiban.veerasooran@microchip.com>
L: netdev@vger.kernel.org
S: Maintained
F: Documentation/networking/oa-tc6-framework.rst
-F: drivers/net/ethernet/oa_tc6.c
+F: drivers/net/ethernet/oa_tc6/oa_tc6*
F: include/linux/oa_tc6.h
OPEN FIRMWARE AND FLATTENED DEVICE TREE
diff --git a/drivers/net/ethernet/Kconfig b/drivers/net/ethernet/Kconfig
index 78c79ad7bba5..49d93488ba52 100644
--- a/drivers/net/ethernet/Kconfig
+++ b/drivers/net/ethernet/Kconfig
@@ -134,6 +134,7 @@ source "drivers/net/ethernet/netronome/Kconfig"
source "drivers/net/ethernet/8390/Kconfig"
source "drivers/net/ethernet/nvidia/Kconfig"
source "drivers/net/ethernet/nxp/Kconfig"
+source "drivers/net/ethernet/oa_tc6/Kconfig"
source "drivers/net/ethernet/oki-semi/Kconfig"
config ETHOC
@@ -146,17 +147,6 @@ config ETHOC
help
Say Y here if you want to use the OpenCores 10/100 Mbps Ethernet MAC.
-config OA_TC6
- tristate "OPEN Alliance TC6 10BASE-T1x MAC-PHY support" if COMPILE_TEST
- depends on SPI
- select PHYLIB
- help
- This library implements OPEN Alliance TC6 10BASE-T1x MAC-PHY
- Serial Interface protocol for supporting 10BASE-T1x MAC-PHYs.
-
- To know the implementation details, refer documentation in
- <file:Documentation/networking/oa-tc6-framework.rst>.
-
source "drivers/net/ethernet/pasemi/Kconfig"
source "drivers/net/ethernet/pensando/Kconfig"
source "drivers/net/ethernet/qlogic/Kconfig"
diff --git a/drivers/net/ethernet/Makefile b/drivers/net/ethernet/Makefile
index bba55d9af387..77b11d5a7abf 100644
--- a/drivers/net/ethernet/Makefile
+++ b/drivers/net/ethernet/Makefile
@@ -71,6 +71,7 @@ obj-$(CONFIG_NET_VENDOR_NETRONOME) += netronome/
obj-$(CONFIG_NET_VENDOR_NI) += ni/
obj-$(CONFIG_NET_VENDOR_NVIDIA) += nvidia/
obj-$(CONFIG_LPC_ENET) += nxp/
+obj-$(CONFIG_OA_TC6) += oa_tc6/
obj-$(CONFIG_NET_VENDOR_OKI) += oki-semi/
obj-$(CONFIG_ETHOC) += ethoc.o
obj-$(CONFIG_NET_VENDOR_PASEMI) += pasemi/
@@ -104,4 +105,3 @@ obj-$(CONFIG_NET_VENDOR_XILINX) += xilinx/
obj-$(CONFIG_NET_VENDOR_XIRCOM) += xircom/
obj-$(CONFIG_NET_VENDOR_SYNOPSYS) += synopsys/
obj-$(CONFIG_NET_VENDOR_PENSANDO) += pensando/
-obj-$(CONFIG_OA_TC6) += oa_tc6.o
diff --git a/drivers/net/ethernet/oa_tc6/Kconfig b/drivers/net/ethernet/oa_tc6/Kconfig
new file mode 100644
index 000000000000..97345f345fb9
--- /dev/null
+++ b/drivers/net/ethernet/oa_tc6/Kconfig
@@ -0,0 +1,16 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# OA TC6 10BASE-T1x MAC-PHY configuration
+#
+
+config OA_TC6
+ tristate "OPEN Alliance TC6 10BASE-T1x MAC-PHY support"
+ depends on SPI
+ select PHYLIB
+ help
+ This library implements OPEN Alliance TC6 10BASE-T1x MAC-PHY
+ Serial Interface protocol for supporting 10BASE-T1x MAC-PHYs.
+
+ To know the implementation details, refer documentation in
+ <file:Documentation/networking/oa-tc6-framework.rst>.
+
diff --git a/drivers/net/ethernet/oa_tc6/Makefile b/drivers/net/ethernet/oa_tc6/Makefile
new file mode 100644
index 000000000000..f24aae852ef2
--- /dev/null
+++ b/drivers/net/ethernet/oa_tc6/Makefile
@@ -0,0 +1,7 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Makefile for OA TC6 10BASE-T1x MAC-PHY
+#
+
+obj-$(CONFIG_OA_TC6) := oa_tc6_mod.o
+oa_tc6_mod-objs := oa_tc6.o
diff --git a/drivers/net/ethernet/oa_tc6.c b/drivers/net/ethernet/oa_tc6/oa_tc6.c
similarity index 100%
rename from drivers/net/ethernet/oa_tc6.c
rename to drivers/net/ethernet/oa_tc6/oa_tc6.c
--
2.43.0
^ permalink raw reply related
* [PATCH net-next v5 01/15] net: phy: Helper to read and write through C45 without lock
From: Selvamani Rajagopal via B4 Relay @ 2026-06-14 17:00 UTC (permalink / raw)
To: Andrew Lunn, Piergiorgio Beruto, Heiner Kallweit, Russell King,
David S. Miller, Eric Dumazet, Jakub Kicinski, Paolo Abeni,
Andrew Lunn, Parthiban Veerasooran, Selva Rajagopal,
Richard Cochran, Rob Herring, Krzysztof Kozlowski, Conor Dooley,
Simon Horman, Jonathan Corbet, Shuah Khan
Cc: netdev, linux-kernel, devicetree, linux-doc, Jerry Ray,
Selvamani Rajagopal
In-Reply-To: <20260614-s2500-mac-phy-support-v5-0-89874b72f725@onsemi.com>
From: Selvamani Rajagopal <Selvamani.Rajagopal@onsemi.com>
Generic helper function to initiate read and write through C45 bus
protocol without mdio bus lock. This will help PHYs to avoid indirect C22
API calls for C45 bus protocol which may not be supported by the PHY.
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Selvamani Rajagopal <Selvamani.Rajagopal@onsemi.com>
---
changes in v5
- no change
changes in v4
- lockdep_assert_held added to ensure correct calling convention
changes in v3
- Added the genphy APIs to initiate Clause 45 register read/write
- first patch
---
drivers/net/phy/phy_device.c | 55 ++++++++++++++++++++++++++++++++++++++++++++
include/linux/phy.h | 4 ++++
2 files changed, 59 insertions(+)
diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
index 0615228459ef..b82b99d08132 100644
--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c
@@ -2787,6 +2787,61 @@ int genphy_write_mmd_unsupported(struct phy_device *phdev, int devnum,
}
EXPORT_SYMBOL(genphy_write_mmd_unsupported);
+/**
+ * genphy_phy_read_mmd - Helper for reading a register without lock
+ * from the given MMD and PHY.
+ * @phydev: The phy_device struct
+ * @devnum: The MMD to read from
+ * @regnum: The register on the MMD to read
+ *
+ * Description: PHYs can have both C22 and C45 registers space. Once PHY
+ * is discovered via C22 bus protocol, it uses C22 indirect access to
+ * access C45 registers. Some PHYs, like 10Base-T1S PHYs defined by OPEN
+ * Alliance 10BASE‑T1x, support only direct access.
+ *
+ * If PHY indicates C45 support through DTS entry, it avoid C22 APIs
+ * entirely and therefore generic MDIO registers are inaccessible.
+ *
+ * MDIO bus isn't locked here because when called through read_mmd
+ * callback of phy_driver, caller is expected to lock the bus as
+ * implemented in phy_read_mmd.
+ *
+ * Returns: Register value if successful, negative error code on failure.
+ */
+int genphy_phy_read_mmd(struct phy_device *phydev, int devnum,
+ u16 regnum)
+{
+ struct mii_bus *bus = phydev->mdio.bus;
+ int addr = phydev->mdio.addr;
+
+ lockdep_assert_held(&bus->mdio_lock);
+ return __mdiobus_c45_read(bus, addr, devnum, regnum);
+}
+EXPORT_SYMBOL(genphy_phy_read_mmd);
+
+/**
+ * genphy_phy_write_mmd - Helper for writing a register without lock
+ * to the given MMD and PHY.
+ * @phydev: The phy_device struct
+ * @devnum: The MMD to write to
+ * @regnum: The register on the MMD to write
+ * @val: Value to write
+ *
+ * Description: Similar to genphy_phy_read_mmd
+ *
+ * Returns: 0 if successful, negative error code on failure.
+ */
+int genphy_phy_write_mmd(struct phy_device *phydev, int devnum,
+ u16 regnum, u16 val)
+{
+ struct mii_bus *bus = phydev->mdio.bus;
+ int addr = phydev->mdio.addr;
+
+ lockdep_assert_held(&bus->mdio_lock);
+ return __mdiobus_c45_write(bus, addr, devnum, regnum, val);
+}
+EXPORT_SYMBOL(genphy_phy_write_mmd);
+
int genphy_suspend(struct phy_device *phydev)
{
return phy_set_bits(phydev, MII_BMCR, BMCR_PDOWN);
diff --git a/include/linux/phy.h b/include/linux/phy.h
index 199a7aaa341b..8266dd4a8dbe 100644
--- a/include/linux/phy.h
+++ b/include/linux/phy.h
@@ -2301,6 +2301,10 @@ int genphy_read_mmd_unsupported(struct phy_device *phdev, int devad,
u16 regnum);
int genphy_write_mmd_unsupported(struct phy_device *phdev, int devnum,
u16 regnum, u16 val);
+int genphy_phy_write_mmd(struct phy_device *phydev, int devnum,
+ u16 regnum, u16 val);
+int genphy_phy_read_mmd(struct phy_device *phydev, int devnum,
+ u16 regnum);
/* Clause 37 */
int genphy_c37_config_aneg(struct phy_device *phydev);
--
2.43.0
^ permalink raw reply related
* [PATCH net-next v5 02/15] net: phy: Helper to modify PHY loopback mode only
From: Selvamani Rajagopal via B4 Relay @ 2026-06-14 17:00 UTC (permalink / raw)
To: Andrew Lunn, Piergiorgio Beruto, Heiner Kallweit, Russell King,
David S. Miller, Eric Dumazet, Jakub Kicinski, Paolo Abeni,
Andrew Lunn, Parthiban Veerasooran, Selva Rajagopal,
Richard Cochran, Rob Herring, Krzysztof Kozlowski, Conor Dooley,
Simon Horman, Jonathan Corbet, Shuah Khan
Cc: netdev, linux-kernel, devicetree, linux-doc, Jerry Ray,
Selvamani Rajagopal
In-Reply-To: <20260614-s2500-mac-phy-support-v5-0-89874b72f725@onsemi.com>
From: Selvamani Rajagopal <Selvamani.Rajagopal@onsemi.com>
Generic helper function to modify loopback bit of the PHY without
modifying any other bit. This will help the PHYs that may have fixed
speed, like 10Base-T1S or PHYs that don't need any other settings
to set them in loopback mode.
Signed-off-by: Selvamani Rajagopal <Selvamani.Rajagopal@onsemi.com>
---
changes in v5
- No change
changes in v4
- Created a new genphy API to set the loopback. No other PHY
registers touched.
---
drivers/net/phy/dp83867.c | 11 +----------
drivers/net/phy/phy_device.c | 20 ++++++++++++++++++++
include/linux/phy.h | 2 ++
3 files changed, 23 insertions(+), 10 deletions(-)
diff --git a/drivers/net/phy/dp83867.c b/drivers/net/phy/dp83867.c
index 88255e92b4cd..01ea2e8dd253 100644
--- a/drivers/net/phy/dp83867.c
+++ b/drivers/net/phy/dp83867.c
@@ -991,15 +991,6 @@ static void dp83867_link_change_notify(struct phy_device *phydev)
}
}
-static int dp83867_loopback(struct phy_device *phydev, bool enable, int speed)
-{
- if (enable && speed)
- return -EOPNOTSUPP;
-
- return phy_modify(phydev, MII_BMCR, BMCR_LOOPBACK,
- enable ? BMCR_LOOPBACK : 0);
-}
-
static int
dp83867_led_brightness_set(struct phy_device *phydev,
u8 index, enum led_brightness brightness)
@@ -1204,7 +1195,7 @@ static struct phy_driver dp83867_driver[] = {
.resume = dp83867_resume,
.link_change_notify = dp83867_link_change_notify,
- .set_loopback = dp83867_loopback,
+ .set_loopback = genphy_loopback_fixed_speed,
.led_brightness_set = dp83867_led_brightness_set,
.led_hw_is_supported = dp83867_led_hw_is_supported,
diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
index b82b99d08132..11fd204eea16 100644
--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c
@@ -2842,6 +2842,26 @@ int genphy_phy_write_mmd(struct phy_device *phydev, int devnum,
}
EXPORT_SYMBOL(genphy_phy_write_mmd);
+/**
+ * genphy_loopback_fixed_speed - Helper to modify the PHY loopback mode
+ * without affecting any other settings.
+ * @phydev: The phy_device struct
+ * @enable: Flag to enable or disable the PHY level loopback.
+ * @speed: Speed setting. Not expected to be set. Error if it is set.
+ *
+ * Returns: 0 if successful, negative error code on failure.
+ */
+int genphy_loopback_fixed_speed(struct phy_device *phydev, bool enable,
+ int speed)
+{
+ if (enable && speed)
+ return -EOPNOTSUPP;
+
+ return phy_modify(phydev, MII_BMCR, BMCR_LOOPBACK,
+ enable ? BMCR_LOOPBACK : 0);
+}
+EXPORT_SYMBOL(genphy_loopback_fixed_speed);
+
int genphy_suspend(struct phy_device *phydev)
{
return phy_set_bits(phydev, MII_BMCR, BMCR_PDOWN);
diff --git a/include/linux/phy.h b/include/linux/phy.h
index 8266dd4a8dbe..61bcd71a3143 100644
--- a/include/linux/phy.h
+++ b/include/linux/phy.h
@@ -2301,6 +2301,8 @@ int genphy_read_mmd_unsupported(struct phy_device *phdev, int devad,
u16 regnum);
int genphy_write_mmd_unsupported(struct phy_device *phdev, int devnum,
u16 regnum, u16 val);
+int genphy_loopback_fixed_speed(struct phy_device *phydev, bool enable,
+ int speed);
int genphy_phy_write_mmd(struct phy_device *phydev, int devnum,
u16 regnum, u16 val);
int genphy_phy_read_mmd(struct phy_device *phydev, int devnum,
--
2.43.0
^ permalink raw reply related
* [PATCH net-next v5 00/15] Support for onsemi's S2500 10Base-T1S MAC-PHY
From: Selvamani Rajagopal via B4 Relay @ 2026-06-14 17:00 UTC (permalink / raw)
To: Andrew Lunn, Piergiorgio Beruto, Heiner Kallweit, Russell King,
David S. Miller, Eric Dumazet, Jakub Kicinski, Paolo Abeni,
Andrew Lunn, Parthiban Veerasooran, Selva Rajagopal,
Richard Cochran, Rob Herring, Krzysztof Kozlowski, Conor Dooley,
Simon Horman, Jonathan Corbet, Shuah Khan
Cc: netdev, linux-kernel, devicetree, linux-doc, Jerry Ray,
Selvamani Rajagopal
This patch series brings support for onsemi's S2500 that iss
IEEE 802.3cg compliant Ethernet transceiver with an integrated
Media Access Controller (MAC-PHY)
Driver implementation is compatible and works with OA TC6
framework that is already present. S2500 driver supports
hardware timestamping.
Driver has support for running selftest and loopback tests.
Through ethtool, it can provide traffic stats, rmon stats,
and timestamping related traffic stats.
As S2500 has an internal PHY, changes have been added
to onsemi's PHY driver to support this device.
---
Changes in v5:
- kernel doc related changes in oa_tc.c, onsemi driver files and
oa tc6 rst file
- Link to v4: https://lore.kernel.org/r/20260605-s2500-mac-phy-support-v4-0-de0fbc13c6d8@onsemi.com
Changes in v4:
- Added return value comment for genphy_read/write_phy_mmd functions
- Added genphy_loopback_fixed_speed helper function to be used in
set_loopback callbacks
- Updated networking documentation for OA TC6 framework to elaborate
on what is expected in the ptp_clock_info structure for registration.
- added spi-max-frequency in YAML file based on alert from sashiko-bot
- Removed model/version from the onsemi driver's private structure as
they were useful as "information-only" data.
- Replaced the non-standard selftest with Linux's standard selftest
and made it as a separate patch
- Changed bit manipulation, shift operations to use macros so that
it is clean and readable.
- added new read_register and write_register apis with _mms postfix
so that MMS (memory map selector) can be given as a parameter.
- Fixed the wrong condition check with NETIF_F_RXFCS to subtract
FCS size from the length of the frame.
To: Andrew Lunn <andrew@lunn.ch>
To: Piergiorgio Beruto <pier.beruto@onsemi.com>
To: Heiner Kallweit <hkallweit1@gmail.com>
To: Russell King <linux@armlinux.org.uk>
To: David S. Miller <davem@davemloft.net>
To: Eric Dumazet <edumazet@google.com>
To: Jakub Kicinski <kuba@kernel.org>
To: Paolo Abeni <pabeni@redhat.com>
To: Andrew Lunn <andrew+netdev@lunn.ch>
To: Parthiban Veerasooran <parthiban.veerasooran@microchip.com>
To: Selva Rajagopal <selvamani.rajagopal@onsemi.com>
To: Richard Cochran <richardcochran@gmail.com>
To: Rob Herring <robh@kernel.org>
To: Krzysztof Kozlowski <krzk+dt@kernel.org>
To: Conor Dooley <conor+dt@kernel.org>
To: Simon Horman <horms@kernel.org>
To: Jonathan Corbet <corbet@lwn.net>
To: Shuah Khan <skhan@linuxfoundation.org>
Cc: netdev@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: devicetree@vger.kernel.org
Cc: linux-doc@vger.kernel.org
Cc: Jerry Ray <jerry.ray@microchip.com>
Signed-off-by: Selvamani Rajagopal <Selvamani.Rajagopal@onsemi.com>
---
Selvamani Rajagopal (15):
net: phy: Helper to read and write through C45 without lock
net: phy: Helper to modify PHY loopback mode only
net: ethernet: oa_tc6: Move oa_tc6.c to its own directory
net: phy: microchip_t1s: Use generic APIs for C45 read and write
net: ethernet: oa_tc6: Move constant definitions to header file
net: ethernet: oa_tc6: Support for hardware timestamp
net: ethernet: oa_tc6: Support for vendor specific MMS
net: ethernet: oa_tc6: read, write interface with MMS option
net: phy: ncn26000: Support for onsemi's S2500 internal phy
net: phy: ncn26000: Enable enhanced noise immunity
net: phy: ncn26000: Support for loopback
onsemi: s2500: Add driver support for TS2500 MAC-PHY
onsemi: s2500: Added selftest support to onsemi's S2500 driver
dt-bindings: net: add onsemi's S2500
Documentation: networking: Add timestamp related APIs to OA TC6 framework
.../devicetree/bindings/net/onnn,s2500.yaml | 67 +++
Documentation/networking/oa-tc6-framework.rst | 80 +++
MAINTAINERS | 13 +-
drivers/net/ethernet/Kconfig | 12 +-
drivers/net/ethernet/Makefile | 2 +-
drivers/net/ethernet/microchip/lan865x/lan865x.c | 61 +-
drivers/net/ethernet/oa_tc6/Kconfig | 16 +
drivers/net/ethernet/oa_tc6/Makefile | 7 +
drivers/net/ethernet/{ => oa_tc6}/oa_tc6.c | 465 +++++++++------
drivers/net/ethernet/oa_tc6/oa_tc6_ptp.c | 67 +++
drivers/net/ethernet/oa_tc6/oa_tc6_std_def.h | 190 +++++++
drivers/net/ethernet/oa_tc6/oa_tc6_tstamp.c | 201 +++++++
drivers/net/ethernet/onsemi/Kconfig | 21 +
drivers/net/ethernet/onsemi/Makefile | 7 +
drivers/net/ethernet/onsemi/s2500/Kconfig | 22 +
drivers/net/ethernet/onsemi/s2500/Makefile | 7 +
drivers/net/ethernet/onsemi/s2500/s2500_ethtool.c | 354 ++++++++++++
drivers/net/ethernet/onsemi/s2500/s2500_hw_def.h | 225 ++++++++
drivers/net/ethernet/onsemi/s2500/s2500_main.c | 632 +++++++++++++++++++++
drivers/net/ethernet/onsemi/s2500/s2500_ptp.c | 233 ++++++++
drivers/net/phy/dp83867.c | 11 +-
drivers/net/phy/microchip_t1s.c | 32 +-
drivers/net/phy/ncn26000.c | 63 +-
drivers/net/phy/phy_device.c | 75 +++
include/linux/oa_tc6.h | 36 ++
include/linux/phy.h | 6 +
26 files changed, 2655 insertions(+), 250 deletions(-)
---
base-commit: 2319688890d97c63da423a3c57c23b4ab5952dfc
change-id: 20260601-s2500-mac-phy-support-4f3ae920fb73
Best regards,
--
Selvamani Rajagopal <Selvamani.Rajagopal@onsemi.com>
^ permalink raw reply
* [PATCH net-next v5 06/15] net: ethernet: oa_tc6: Support for hardware timestamp
From: Selvamani Rajagopal via B4 Relay @ 2026-06-14 17:00 UTC (permalink / raw)
To: Andrew Lunn, Piergiorgio Beruto, Heiner Kallweit, Russell King,
David S. Miller, Eric Dumazet, Jakub Kicinski, Paolo Abeni,
Andrew Lunn, Parthiban Veerasooran, Selva Rajagopal,
Richard Cochran, Rob Herring, Krzysztof Kozlowski, Conor Dooley,
Simon Horman, Jonathan Corbet, Shuah Khan
Cc: netdev, linux-kernel, devicetree, linux-doc, Jerry Ray,
Selvamani Rajagopal
In-Reply-To: <20260614-s2500-mac-phy-support-v5-0-89874b72f725@onsemi.com>
From: Selvamani Rajagopal <Selvamani.Rajagopal@onsemi.com>
PTP register/unregister calls are implemented in oa_tc6_ptp.c.
The APIs that work with the hardware for timestamp is provided
by vendor code as it may be vendor dependent.
Interface for ndo_hwtstamp_set/get, ioctl, control and status
callback for ethtool are provided to support hardware timestamp
feature.
Besides ioctl interface, hardware timestamp functions that handles
header and footer data are in oa_tc6.c. Helper functions are in
oa_tc6_tstamp.c.
Signed-off-by: Selvamani Rajagopal <Selvamani.Rajagopal@onsemi.com>
---
changes in v5
- As subtracting skb len by FCS size is considered bug, changes
are removed. Will be fixed in stable branch (net repo)
changes in v4
- Fixed the condition check for subtracting the FCS size
from skb len.
changes in v3
- Replaced warning printk with ratelimited printk
- Checking the hardware register before enabling hardware
timestamp
changes in v1
- Added hardware timestamp support to the OA TC6 framework.
---
MAINTAINERS | 1 +
drivers/net/ethernet/oa_tc6/Makefile | 2 +-
drivers/net/ethernet/oa_tc6/oa_tc6.c | 214 +++++++++++++++++++++++++--
drivers/net/ethernet/oa_tc6/oa_tc6_ptp.c | 67 +++++++++
drivers/net/ethernet/oa_tc6/oa_tc6_std_def.h | 33 +++++
drivers/net/ethernet/oa_tc6/oa_tc6_tstamp.c | 202 +++++++++++++++++++++++++
include/linux/oa_tc6.h | 12 ++
7 files changed, 516 insertions(+), 15 deletions(-)
diff --git a/MAINTAINERS b/MAINTAINERS
index 4cee98fc922c..03adc7697dce 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -19998,6 +19998,7 @@ F: drivers/rtc/rtc-optee.c
OPEN ALLIANCE 10BASE-T1S MACPHY SERIAL INTERFACE FRAMEWORK
M: Parthiban Veerasooran <parthiban.veerasooran@microchip.com>
+M: Selva Rajagopal <selvamani.rajagopal@onsemi.com> (timestamp support)
L: netdev@vger.kernel.org
S: Maintained
F: Documentation/networking/oa-tc6-framework.rst
diff --git a/drivers/net/ethernet/oa_tc6/Makefile b/drivers/net/ethernet/oa_tc6/Makefile
index f24aae852ef2..964f668efc2d 100644
--- a/drivers/net/ethernet/oa_tc6/Makefile
+++ b/drivers/net/ethernet/oa_tc6/Makefile
@@ -4,4 +4,4 @@
#
obj-$(CONFIG_OA_TC6) := oa_tc6_mod.o
-oa_tc6_mod-objs := oa_tc6.o
+oa_tc6_mod-objs := oa_tc6.o oa_tc6_ptp.o oa_tc6_tstamp.o
diff --git a/drivers/net/ethernet/oa_tc6/oa_tc6.c b/drivers/net/ethernet/oa_tc6/oa_tc6.c
index c7d70d37ba53..9410cecfdc2a 100644
--- a/drivers/net/ethernet/oa_tc6/oa_tc6.c
+++ b/drivers/net/ethernet/oa_tc6/oa_tc6.c
@@ -13,6 +13,15 @@
#include "oa_tc6_std_def.h"
+struct oa_tc6_ts_info_rx {
+ bool rtsa;
+ bool rtsp;
+};
+
+struct oa_tc6_ts_info_tx {
+ u8 tsc;
+};
+
static int oa_tc6_spi_transfer(struct oa_tc6 *tc6,
enum oa_tc6_header_type header_type, u16 length)
{
@@ -47,6 +56,152 @@ static int oa_tc6_get_parity(u32 p)
return !((p >> 28) & 1);
}
+static struct oa_tc6_ts_info_tx *oa_tc6_tsinfo_tx(struct sk_buff *skb)
+{
+ return (struct oa_tc6_ts_info_tx *)(skb->cb);
+}
+
+static struct oa_tc6_ts_info_rx *oa_tc6_tsinfo_rx(struct sk_buff *skb)
+{
+ return (struct oa_tc6_ts_info_rx *)(skb->cb);
+}
+
+static void oa_tc6_defer_for_hwtstamp(struct oa_tc6 *tc6,
+ struct sk_buff *skb)
+{
+ if (!tc6->hw_tstamp_enabled)
+ return;
+ if (!skb || (skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP) == 0)
+ return;
+ if (tc6->ts_config.tx_type != HWTSTAMP_TX_ON) {
+ tc6->tx_hwtstamp_lost++;
+ return;
+ }
+
+ skb_shinfo(skb)->tx_flags |= SKBTX_IN_PROGRESS;
+ u8 ret = tc6->tx_ts_idx++;
+
+ if (ret == OA_TC6_TTSCC_REG_ID)
+ tc6->tx_ts_idx = OA_TC6_TTSCA_REG_ID;
+ oa_tc6_tsinfo_tx(skb)->tsc = ret;
+
+ list_add_tail(&skb->list, &tc6->tx_ts_skb_q);
+}
+
+static int oa_tc6_process_deferred_skb(struct oa_tc6 *tc6, u8 tsc)
+{
+ struct skb_shared_hwtstamps tstamp;
+ struct oa_tc6_ts_info_tx *ski;
+ struct sk_buff *skb, *tmp;
+ bool found = false;
+ int ret = 0;
+
+ /* Size of data must match OA_TC6_TSTAMP_SZ */
+ u32 data[2];
+
+ list_for_each_entry_safe(skb, tmp, &tc6->tx_ts_skb_q, list) {
+ ski = oa_tc6_tsinfo_tx(skb);
+ if (ski->tsc != tsc)
+ continue;
+ if (found) {
+ dev_warn_ratelimited(&tc6->spi->dev,
+ "Multiple skbs. tsc = %d\n",
+ tsc);
+ tc6->tx_hwtstamp_err++;
+ }
+ found = true;
+ list_del(&skb->list);
+
+ /* Retrieve the timestamping info */
+ ret = oa_tc6_read_registers(tc6,
+ OA_TC6_REG_TTSCA_HIGH +
+ 2 * (tsc - 1), &data[0], 2);
+
+ if (!ret) {
+ tstamp.hwtstamp = ktime_set(data[0], data[1]);
+ skb_tstamp_tx(skb, &tstamp);
+ tc6->tx_hwtstamp_pkts++;
+ }
+
+ dev_kfree_skb(skb);
+ }
+ return ret;
+}
+
+static void oa_tc6_events_handle(struct oa_tc6 *tc6, u32 val)
+{
+ /* Check TX timestamping */
+ if (val & STATUS0_TTSCAA)
+ oa_tc6_process_deferred_skb(tc6, OA_TC6_TTSCA_REG_ID);
+
+ if (val & STATUS0_TTSCAB)
+ oa_tc6_process_deferred_skb(tc6, OA_TC6_TTSCB_REG_ID);
+
+ if (val & STATUS0_TTSCAC)
+ oa_tc6_process_deferred_skb(tc6, OA_TC6_TTSCC_REG_ID);
+}
+
+static void oa_tc6_update_ts_in_rx_skb(struct oa_tc6 *tc6)
+{
+ struct sk_buff *skb = tc6->rx_skb;
+ struct oa_tc6_ts_info_rx *ski;
+ u32 ts[2];
+
+ if (!tc6->hw_tstamp_enabled)
+ return;
+ ski = oa_tc6_tsinfo_rx(skb);
+ if (!ski->rtsa)
+ return;
+
+ ts[0] = be32_to_cpu(*((u32 *)(skb->data)));
+ ts[1] = be32_to_cpu(*((u32 *)(skb->data) + 1));
+
+ /* Check parity */
+ if ((oa_tc6_get_parity(ts[0]) ^ oa_tc6_get_parity(ts[1])) ==
+ !ski->rtsp) {
+ struct skb_shared_hwtstamps *hw_ts;
+
+ /* Report timestamp to the upper layers */
+ hw_ts = skb_hwtstamps(skb);
+ memset(hw_ts, 0, sizeof(*hw_ts));
+ hw_ts->hwtstamp = ktime_set(ts[0], ts[1]);
+ }
+ skb_pull(skb, sizeof(ts));
+}
+
+static int oa_tc6_update_standard_capability(struct oa_tc6 *tc6)
+{
+ u32 regval = 0;
+ int ret;
+
+ ret = oa_tc6_read_register(tc6, OA_TC6_REG_STDCAP, ®val);
+ if (ret)
+ return ret;
+ if (regval & STDCAP_FRAME_TIMESTAMP_CAPABILITY)
+ tc6->hw_tstamp_supported = true;
+ return 0;
+}
+
+/**
+ * oa_tc6_ioctl - generic ioctl interface for MAC-PHY drivers.
+ * @tc6: oa_tc6 struct.
+ * @rq: request from socket interface
+ * @cmd: value to set/get timestamp configuration
+ *
+ * Return: 0 on success otherwise failed.
+ */
+int oa_tc6_ioctl(struct oa_tc6 *tc6, struct ifreq *rq, int cmd)
+{
+ if (!netif_running(tc6->netdev))
+ return -EINVAL;
+
+ if (cmd == SIOCSHWTSTAMP || cmd == SIOCGHWTSTAMP)
+ return oa_tc6_tstamp_ioctl(tc6, rq, cmd);
+ else
+ return phy_do_ioctl_running(tc6->netdev, rq, cmd);
+}
+EXPORT_SYMBOL_GPL(oa_tc6_ioctl);
+
static __be32 oa_tc6_prepare_ctrl_header(u32 addr, u8 length,
enum oa_tc6_register_op reg_op)
{
@@ -538,6 +693,9 @@ static int oa_tc6_process_extended_status(struct oa_tc6 *tc6)
return ret;
}
+ if ((value & STATUS0_TTSCA_MASK) != 0)
+ oa_tc6_events_handle(tc6, value & STATUS0_TTSCA_MASK);
+
/* Clear the error interrupts status */
ret = oa_tc6_write_register(tc6, OA_TC6_REG_STATUS0, value);
if (ret) {
@@ -609,6 +767,8 @@ static int oa_tc6_process_rx_chunk_footer(struct oa_tc6 *tc6, u32 footer)
static void oa_tc6_submit_rx_skb(struct oa_tc6 *tc6)
{
+ oa_tc6_update_ts_in_rx_skb(tc6);
+
tc6->rx_skb->protocol = eth_type_trans(tc6->rx_skb, tc6->netdev);
tc6->netdev->stats.rx_packets++;
tc6->netdev->stats.rx_bytes += tc6->rx_skb->len;
@@ -623,24 +783,29 @@ static void oa_tc6_update_rx_skb(struct oa_tc6 *tc6, u8 *payload, u8 length)
memcpy(skb_put(tc6->rx_skb, length), payload, length);
}
-static int oa_tc6_allocate_rx_skb(struct oa_tc6 *tc6)
+static int oa_tc6_allocate_rx_skb(struct oa_tc6 *tc6, u32 footer)
{
+ struct oa_tc6_ts_info_rx *ski;
+
tc6->rx_skb = netdev_alloc_skb_ip_align(tc6->netdev, tc6->netdev->mtu +
- ETH_HLEN + ETH_FCS_LEN);
+ ETH_HLEN + ETH_FCS_LEN + OA_TC6_TSTAMP_SZ);
if (!tc6->rx_skb) {
tc6->netdev->stats.rx_dropped++;
return -ENOMEM;
}
+ ski = oa_tc6_tsinfo_rx(tc6->rx_skb);
+ ski->rtsa = FIELD_GET(OA_TC6_DATA_FOOTER_RTSA_VALID, footer);
+ ski->rtsp = FIELD_GET(OA_TC6_DATA_FOOTER_RTSP_VALID, footer);
return 0;
}
static int oa_tc6_prcs_complete_rx_frame(struct oa_tc6 *tc6, u8 *payload,
- u16 size)
+ u16 size, u32 footer)
{
int ret;
- ret = oa_tc6_allocate_rx_skb(tc6);
+ ret = oa_tc6_allocate_rx_skb(tc6, footer);
if (ret)
return ret;
@@ -651,11 +816,11 @@ static int oa_tc6_prcs_complete_rx_frame(struct oa_tc6 *tc6, u8 *payload,
return 0;
}
-static int oa_tc6_prcs_rx_frame_start(struct oa_tc6 *tc6, u8 *payload, u16 size)
+static int oa_tc6_prcs_rx_frame_start(struct oa_tc6 *tc6, u8 *payload, u16 size, u32 footer)
{
int ret;
- ret = oa_tc6_allocate_rx_skb(tc6);
+ ret = oa_tc6_allocate_rx_skb(tc6, footer);
if (ret)
return ret;
@@ -700,7 +865,7 @@ static int oa_tc6_prcs_rx_chunk_payload(struct oa_tc6 *tc6, u8 *data,
size = end_byte_offset + 1 - start_byte_offset;
return oa_tc6_prcs_complete_rx_frame(tc6,
&data[start_byte_offset],
- size);
+ size, footer);
}
/* Process the chunk with only rx frame start */
@@ -708,7 +873,7 @@ static int oa_tc6_prcs_rx_chunk_payload(struct oa_tc6 *tc6, u8 *data,
size = OA_TC6_CHUNK_PAYLOAD_SIZE - start_byte_offset;
return oa_tc6_prcs_rx_frame_start(tc6,
&data[start_byte_offset],
- size);
+ size, footer);
}
/* Process the chunk with only rx frame end */
@@ -733,7 +898,7 @@ static int oa_tc6_prcs_rx_chunk_payload(struct oa_tc6 *tc6, u8 *data,
size = OA_TC6_CHUNK_PAYLOAD_SIZE - start_byte_offset;
return oa_tc6_prcs_rx_frame_start(tc6,
&data[start_byte_offset],
- size);
+ size, footer);
}
/* Process the chunk with ongoing rx frame data */
@@ -787,13 +952,15 @@ static int oa_tc6_process_spi_data_rx_buf(struct oa_tc6 *tc6, u16 length)
}
static __be32 oa_tc6_prepare_data_header(bool data_valid, bool start_valid,
- bool end_valid, u8 end_byte_offset)
+ bool end_valid, u8 end_byte_offset,
+ u8 tsc)
{
u32 header = FIELD_PREP(OA_TC6_DATA_HEADER_DATA_NOT_CTRL,
OA_TC6_DATA_HEADER) |
FIELD_PREP(OA_TC6_DATA_HEADER_DATA_VALID, data_valid) |
FIELD_PREP(OA_TC6_DATA_HEADER_START_VALID, start_valid) |
FIELD_PREP(OA_TC6_DATA_HEADER_END_VALID, end_valid) |
+ FIELD_PREP(OA_TC6_DATA_HEADER_TSC_OFFSET, tsc) |
FIELD_PREP(OA_TC6_DATA_HEADER_END_BYTE_OFFSET,
end_byte_offset);
@@ -812,6 +979,7 @@ static void oa_tc6_add_tx_skb_to_spi_buf(struct oa_tc6 *tc6)
enum oa_tc6_data_start_valid_info start_valid;
u8 end_byte_offset = 0;
u16 length_to_copy;
+ u8 tsc = 0;
/* Initial value is assigned here to avoid more than 80 characters in
* the declaration place.
@@ -821,8 +989,10 @@ static void oa_tc6_add_tx_skb_to_spi_buf(struct oa_tc6 *tc6)
/* Set start valid if the current tx chunk contains the start of the tx
* ethernet frame.
*/
- if (!tc6->tx_skb_offset)
+ if (!tc6->tx_skb_offset) {
start_valid = OA_TC6_DATA_START_VALID;
+ tsc = oa_tc6_tsinfo_tx(tc6->ongoing_tx_skb)->tsc;
+ }
/* If the remaining tx skb length is more than the chunk payload size of
* 64 bytes then copy only 64 bytes and leave the ongoing tx skb for
@@ -843,12 +1013,17 @@ static void oa_tc6_add_tx_skb_to_spi_buf(struct oa_tc6 *tc6)
tc6->tx_skb_offset = 0;
tc6->netdev->stats.tx_bytes += tc6->ongoing_tx_skb->len;
tc6->netdev->stats.tx_packets++;
- kfree_skb(tc6->ongoing_tx_skb);
+
+ /* Free the ones that are not saved for later processing,
+ * like timestamping.
+ */
+ if (!(skb_shinfo(tc6->ongoing_tx_skb)->tx_flags & SKBTX_IN_PROGRESS))
+ kfree_skb(tc6->ongoing_tx_skb);
tc6->ongoing_tx_skb = NULL;
}
*tx_buf = oa_tc6_prepare_data_header(OA_TC6_DATA_VALID, start_valid,
- end_valid, end_byte_offset);
+ end_valid, end_byte_offset, tsc);
tc6->spi_data_tx_buf_offset += OA_TC6_CHUNK_SIZE;
}
@@ -866,6 +1041,8 @@ static u16 oa_tc6_prepare_spi_tx_buf_for_tx_skbs(struct oa_tc6 *tc6)
tc6->ongoing_tx_skb = tc6->waiting_tx_skb;
tc6->waiting_tx_skb = NULL;
spin_unlock_bh(&tc6->tx_skb_lock);
+ oa_tc6_defer_for_hwtstamp(tc6,
+ tc6->ongoing_tx_skb);
}
if (!tc6->ongoing_tx_skb)
break;
@@ -882,7 +1059,7 @@ static void oa_tc6_add_empty_chunks_to_spi_buf(struct oa_tc6 *tc6,
header = oa_tc6_prepare_data_header(OA_TC6_DATA_INVALID,
OA_TC6_DATA_START_INVALID,
- OA_TC6_DATA_END_INVALID, 0);
+ OA_TC6_DATA_END_INVALID, 0, false);
while (needed_empty_chunks--) {
__be32 *tx_buf = tc6->spi_data_tx_buf +
@@ -1073,6 +1250,7 @@ netdev_tx_t oa_tc6_start_xmit(struct oa_tc6 *tc6, struct sk_buff *skb)
spin_lock_bh(&tc6->tx_skb_lock);
tc6->waiting_tx_skb = skb;
spin_unlock_bh(&tc6->tx_skb_lock);
+ oa_tc6_tsinfo_tx(skb)->tsc = 0;
/* Wake spi kthread to perform spi transfer */
wake_up_interruptible(&tc6->spi_wq);
@@ -1103,6 +1281,8 @@ struct oa_tc6 *oa_tc6_init(struct spi_device *spi, struct net_device *netdev)
SET_NETDEV_DEV(netdev, &spi->dev);
mutex_init(&tc6->spi_ctrl_lock);
spin_lock_init(&tc6->tx_skb_lock);
+ tc6->tx_ts_idx = OA_TC6_TTSCA_REG_ID;
+ INIT_LIST_HEAD(&tc6->tx_ts_skb_q);
/* Set the SPI controller to pump at realtime priority */
tc6->spi->rt = true;
@@ -1168,6 +1348,12 @@ struct oa_tc6 *oa_tc6_init(struct spi_device *spi, struct net_device *netdev)
goto phy_exit;
}
+ ret = oa_tc6_update_standard_capability(tc6);
+ if (ret) {
+ dev_err(&tc6->spi->dev, "Failed to read capability\n");
+ goto phy_exit;
+ }
+
init_waitqueue_head(&tc6->spi_wq);
tc6->spi_thread = kthread_run(oa_tc6_spi_thread_handler, tc6,
diff --git a/drivers/net/ethernet/oa_tc6/oa_tc6_ptp.c b/drivers/net/ethernet/oa_tc6/oa_tc6_ptp.c
new file mode 100644
index 000000000000..921191ec6829
--- /dev/null
+++ b/drivers/net/ethernet/oa_tc6/oa_tc6_ptp.c
@@ -0,0 +1,67 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Support for hardware timestamping feature for OPEN Alliance
+ * 10BASE‑T1x MAC‑PHY Serial Interface framework
+ *
+ * Author: Selva Rajagopal <selvamani.rajagopal@onsemi.com>
+ */
+
+#include <linux/hrtimer.h>
+#include <linux/irq.h>
+#include <linux/irqdomain.h>
+#include <linux/kernel.h>
+#include <linux/netdevice.h>
+#include <linux/phylink.h>
+#include <linux/spi/spi.h>
+#include <linux/oa_tc6.h>
+#include <linux/net_tstamp.h>
+#include <linux/ptp_clock_kernel.h>
+#include <linux/delay.h>
+#include <linux/mutex.h>
+#include <linux/ktime.h>
+#include <linux/errno.h>
+
+#include "oa_tc6_std_def.h"
+
+/**
+ * oa_tc6_ptp_register - Registers clock related callbacks
+ * @tc6: oa_tc6 struct.
+ * @info: Describes a PTP hardware clock
+ *
+ * Description: Vendors are expected to set the hardware timestamp
+ * related callbacks before calling this function.
+ */
+int oa_tc6_ptp_register(struct oa_tc6 *tc6, struct ptp_clock_info *info)
+{
+ /* Not supporting hardware timestamp isn't an error */
+ if (!tc6->hw_tstamp_supported)
+ return 0;
+
+ snprintf(info->name, sizeof(info->name), "%s",
+ "OA TC6 PTP clock");
+ tc6->ptp_clock = ptp_clock_register(info, &tc6->spi->dev);
+ if (IS_ERR(tc6->ptp_clock)) {
+ dev_err(&tc6->spi->dev, "Registration of %s failed",
+ info->name);
+ return -EFAULT;
+ }
+ dev_info(&tc6->spi->dev, "%s registered. index %d", info->name,
+ ptp_clock_index(tc6->ptp_clock));
+ return 0;
+}
+EXPORT_SYMBOL_GPL(oa_tc6_ptp_register);
+
+/**
+ * oa_tc6_ptp_unregister - Unregisters clock related callbacks
+ * @tc6: oa_tc6 struct.
+ */
+void oa_tc6_ptp_unregister(struct oa_tc6 *tc6)
+{
+ if (tc6->ptp_clock)
+ ptp_clock_unregister(tc6->ptp_clock);
+}
+EXPORT_SYMBOL_GPL(oa_tc6_ptp_unregister);
+
+MODULE_DESCRIPTION("OPEN Alliance 10BASE‑T1x MAC‑PHY Serial Interface Lib");
+MODULE_AUTHOR("Selva Rajagopal <selvamani.rajagopal@onsemi.com>");
+MODULE_LICENSE("GPL");
diff --git a/drivers/net/ethernet/oa_tc6/oa_tc6_std_def.h b/drivers/net/ethernet/oa_tc6/oa_tc6_std_def.h
index 2d8e28fb46fc..3a12b3228f30 100644
--- a/drivers/net/ethernet/oa_tc6/oa_tc6_std_def.h
+++ b/drivers/net/ethernet/oa_tc6/oa_tc6_std_def.h
@@ -22,6 +22,7 @@
/* Standard Capabilities Register */
#define OA_TC6_REG_STDCAP 0x0002
#define STDCAP_DIRECT_PHY_REG_ACCESS BIT(8)
+#define STDCAP_FRAME_TIMESTAMP_CAPABILITY BIT(6)
/* Reset Control and Status Register */
#define OA_TC6_REG_RESET 0x0003
@@ -31,9 +32,14 @@
#define OA_TC6_REG_CONFIG0 0x0004
#define CONFIG0_SYNC BIT(15)
#define CONFIG0_ZARFE_ENABLE BIT(12)
+#define CONFIG0_FTSE_ENABLE BIT(7)
/* Status Register #0 */
#define OA_TC6_REG_STATUS0 0x0008
+#define STATUS0_TTSCAC BIT(10)
+#define STATUS0_TTSCAB BIT(9)
+#define STATUS0_TTSCAA BIT(8)
+#define STATUS0_TTSCA_MASK GENMASK(10, 8)
#define STATUS0_RESETC BIT(6) /* Reset Complete */
#define STATUS0_HEADER_ERROR BIT(5)
#define STATUS0_LOSS_OF_FRAME_ERROR BIT(4)
@@ -47,6 +53,7 @@
/* Interrupt Mask Register #0 */
#define OA_TC6_REG_INT_MASK0 0x000C
+#define INT_MASK0_TTSCA_MASK GENMASK(10, 8)
#define INT_MASK0_HEADER_ERR_MASK BIT(5)
#define INT_MASK0_LOSS_OF_FRAME_ERR_MASK BIT(4)
#define INT_MASK0_RX_BUFFER_OVERFLOW_ERR_MASK BIT(3)
@@ -56,6 +63,9 @@
#define OA_TC6_PHY_STD_REG_ADDR_BASE 0xFF00
#define OA_TC6_PHY_STD_REG_ADDR_MASK 0x1F
+/* Tx timestamp capture register A (high) */
+#define OA_TC6_REG_TTSCA_HIGH (0x1010)
+
/* Control command header */
#define OA_TC6_CTRL_HEADER_DATA_NOT_CTRL BIT(31)
#define OA_TC6_CTRL_HEADER_WRITE_NOT_READ BIT(29)
@@ -71,6 +81,7 @@
#define OA_TC6_DATA_HEADER_START_WORD_OFFSET GENMASK(19, 16)
#define OA_TC6_DATA_HEADER_END_VALID BIT(14)
#define OA_TC6_DATA_HEADER_END_BYTE_OFFSET GENMASK(13, 8)
+#define OA_TC6_DATA_HEADER_TSC_OFFSET GENMASK(7, 6)
#define OA_TC6_DATA_HEADER_PARITY BIT(0)
/* Data footer */
@@ -82,6 +93,8 @@
#define OA_TC6_DATA_FOOTER_START_VALID BIT(20)
#define OA_TC6_DATA_FOOTER_START_WORD_OFFSET GENMASK(19, 16)
#define OA_TC6_DATA_FOOTER_END_VALID BIT(14)
+#define OA_TC6_DATA_FOOTER_RTSA_VALID BIT(7)
+#define OA_TC6_DATA_FOOTER_RTSP_VALID BIT(6)
#define OA_TC6_DATA_FOOTER_END_BYTE_OFFSET GENMASK(13, 8)
#define OA_TC6_DATA_FOOTER_TX_CREDITS GENMASK(5, 1)
@@ -103,6 +116,12 @@
#define STATUS0_RESETC_POLL_DELAY 1000
#define STATUS0_RESETC_POLL_TIMEOUT 1000000
+#define OA_TC6_TSTAMP_SZ 8
+
+#define OA_TC6_TTSCA_REG_ID 1
+#define OA_TC6_TTSCB_REG_ID 2
+#define OA_TC6_TTSCC_REG_ID 3
+
/* Internal structure for MAC-PHY drivers */
struct oa_tc6 {
struct device *dev;
@@ -127,6 +146,17 @@ struct oa_tc6 {
u8 rx_chunks_available;
bool rx_buf_overflow;
bool int_flag;
+ struct ptp_clock_info ptp_clock_info;
+ struct hwtstamp_config ts_config;
+ struct list_head tx_ts_skb_q;
+ struct ptp_clock *ptp_clock;
+ bool hw_tstamp_supported;
+ bool hw_tstamp_enabled;
+ u32 tx_hwtstamp_pkts;
+ u32 tx_hwtstamp_lost;
+ u32 tx_hwtstamp_err;
+ int vend1_mms;
+ u8 tx_ts_idx;
};
enum oa_tc6_header_type {
@@ -153,5 +183,8 @@ enum oa_tc6_data_end_valid_info {
OA_TC6_DATA_END_INVALID,
OA_TC6_DATA_END_VALID,
};
+
+int oa_tc6_tstamp_ioctl(struct oa_tc6 *tc6, struct ifreq *rq, int cmd);
+
#endif /* OA_TC6_STD_DEF_H */
diff --git a/drivers/net/ethernet/oa_tc6/oa_tc6_tstamp.c b/drivers/net/ethernet/oa_tc6/oa_tc6_tstamp.c
new file mode 100644
index 000000000000..272701a4081d
--- /dev/null
+++ b/drivers/net/ethernet/oa_tc6/oa_tc6_tstamp.c
@@ -0,0 +1,202 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * OPEN Alliance 10BASE‑T1x MAC‑PHY Serial Interface framework
+ *
+ * Author: Selva Rajagopal <selvamani.rajagopal@onsemi.com>
+ */
+
+#include <linux/bitfield.h>
+#include <linux/iopoll.h>
+#include <linux/mdio.h>
+#include <linux/phy.h>
+#include <linux/oa_tc6.h>
+
+#include "oa_tc6_std_def.h"
+
+static int oa_tc6_set_hwtstamp_settings(struct oa_tc6 *tc6)
+{
+ u32 cfg0, irqm, status0;
+ int ret;
+
+ ret = oa_tc6_read_register(tc6, OA_TC6_REG_CONFIG0, &cfg0);
+ if (ret) {
+ dev_err(&tc6->spi->dev, "Failed to read CFG0 register\n");
+ goto out;
+ }
+
+ ret = oa_tc6_read_register(tc6, OA_TC6_REG_INT_MASK0, &irqm);
+ if (ret) {
+ dev_err(&tc6->spi->dev, "failed to read IRQM register\n");
+ goto out;
+ }
+
+ if (tc6->ts_config.tx_type == HWTSTAMP_TX_ON ||
+ tc6->ts_config.rx_filter == HWTSTAMP_FILTER_ALL)
+ cfg0 |= CONFIG0_FTSE_ENABLE;
+ else
+ cfg0 &= ~CONFIG0_FTSE_ENABLE;
+
+ if (tc6->ts_config.tx_type == HWTSTAMP_TX_ON)
+ irqm &= ~INT_MASK0_TTSCA_MASK;
+ else
+ irqm |= INT_MASK0_TTSCA_MASK;
+
+ /* Clear timestamp related IRQs */
+ status0 = STATUS0_TTSCA_MASK;
+ ret = oa_tc6_write_register(tc6, OA_TC6_REG_STATUS0, status0);
+ if (ret) {
+ dev_err(&tc6->spi->dev, "failed to write STATUS0 register\n");
+ goto out;
+ }
+
+ ret = oa_tc6_write_register(tc6, OA_TC6_REG_INT_MASK0, irqm);
+ if (ret) {
+ dev_err(&tc6->spi->dev, "failed to write IRQM register\n");
+ goto out;
+ }
+
+ ret = oa_tc6_write_register(tc6, OA_TC6_REG_CONFIG0, cfg0);
+ if (ret) {
+ dev_err(&tc6->spi->dev, "failed to write CFG0 register\n");
+ goto out;
+ }
+ if (cfg0 & CONFIG0_FTSE_ENABLE)
+ tc6->hw_tstamp_enabled = true;
+ else
+ tc6->hw_tstamp_enabled = false;
+out:
+ return ret;
+}
+
+/**
+ * oa_tc6_hwtstamp_get - gets hardware timestamp config
+ * @tc6: oa_tc6 struct.
+ * @cfg: kernel copy of hardware timestamp config
+ */
+void oa_tc6_hwtstamp_get(struct oa_tc6 *tc6,
+ struct kernel_hwtstamp_config *cfg)
+{
+ hwtstamp_config_to_kernel(cfg, &tc6->ts_config);
+}
+EXPORT_SYMBOL_GPL(oa_tc6_hwtstamp_get);
+
+/**
+ * oa_tc6_hwtstamp_set - sets hardware timestamp config
+ * @tc6: oa_tc6 struct.
+ * @cfg: kernel copy of hardware timestamp config
+ *
+ * Return: 0 on success otherwise failed.
+ */
+int oa_tc6_hwtstamp_set(struct oa_tc6 *tc6,
+ struct kernel_hwtstamp_config *cfg)
+{
+ if (!netif_running(tc6->netdev))
+ return -EIO;
+
+ if (!tc6->hw_tstamp_supported)
+ return -EOPNOTSUPP;
+
+ switch (cfg->tx_type) {
+ case HWTSTAMP_TX_OFF:
+ case HWTSTAMP_TX_ON:
+ break;
+ default:
+ return -ERANGE;
+ }
+
+ switch (cfg->rx_filter) {
+ case HWTSTAMP_FILTER_NONE:
+ case HWTSTAMP_FILTER_ALL:
+ case HWTSTAMP_FILTER_SOME:
+ case HWTSTAMP_FILTER_PTP_V1_L4_EVENT:
+ case HWTSTAMP_FILTER_PTP_V1_L4_SYNC:
+ case HWTSTAMP_FILTER_PTP_V1_L4_DELAY_REQ:
+ case HWTSTAMP_FILTER_PTP_V2_L4_EVENT:
+ case HWTSTAMP_FILTER_PTP_V2_L4_SYNC:
+ case HWTSTAMP_FILTER_PTP_V2_L4_DELAY_REQ:
+ case HWTSTAMP_FILTER_PTP_V2_L2_EVENT:
+ case HWTSTAMP_FILTER_PTP_V2_L2_SYNC:
+ case HWTSTAMP_FILTER_PTP_V2_L2_DELAY_REQ:
+ case HWTSTAMP_FILTER_PTP_V2_EVENT:
+ case HWTSTAMP_FILTER_PTP_V2_SYNC:
+ case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ:
+ case HWTSTAMP_FILTER_NTP_ALL:
+ break;
+ default:
+ return -ERANGE;
+ }
+ hwtstamp_config_from_kernel(&tc6->ts_config, cfg);
+
+ /* Supports timestamping all traffic */
+ if (cfg->rx_filter != HWTSTAMP_FILTER_NONE)
+ tc6->ts_config.rx_filter = HWTSTAMP_FILTER_ALL;
+ return oa_tc6_set_hwtstamp_settings(tc6);
+}
+EXPORT_SYMBOL_GPL(oa_tc6_hwtstamp_set);
+
+/**
+ * oa_tc6_get_ts_stats - Provides timestamping stats
+ * @tc6: oa_tc6 struct.
+ * @ts_stats: ethtool data structure to fill in
+ */
+void oa_tc6_get_ts_stats(struct oa_tc6 *tc6,
+ struct ethtool_ts_stats *stats)
+{
+ stats->pkts = tc6->tx_hwtstamp_pkts;
+ stats->err = tc6->tx_hwtstamp_err;
+ stats->lost = tc6->tx_hwtstamp_lost;
+}
+EXPORT_SYMBOL_GPL(oa_tc6_get_ts_stats);
+
+int oa_tc6_tstamp_ioctl(struct oa_tc6 *tc6, struct ifreq *rq, int cmd)
+{
+ struct kernel_hwtstamp_config kcfg;
+ struct hwtstamp_config tscfg;
+ int ret = 0;
+
+ if (!tc6->hw_tstamp_supported)
+ return -EOPNOTSUPP;
+
+ if (cmd == SIOCSHWTSTAMP) {
+ if (copy_from_user(&tscfg, rq->ifr_data,
+ sizeof(tscfg)))
+ return -EFAULT;
+
+ if (tscfg.flags)
+ return -EINVAL;
+ hwtstamp_config_to_kernel(&kcfg, &tscfg);
+ ret = oa_tc6_hwtstamp_set(tc6, &kcfg);
+ if (ret)
+ return ret;
+ }
+ if (copy_to_user(rq->ifr_data, &tc6->ts_config,
+ sizeof(tc6->ts_config)))
+ ret = -EFAULT;
+ return ret;
+}
+
+/**
+ * oa_tc6_get_ts_info - Provides timestamp info for ethtool
+ * @tc6: oa_tc6 struct.
+ * @info: ethtool timestamping info structure
+ * @ts_stats: ethtool data structure to fill in
+ */
+int oa_tc6_get_ts_info(struct oa_tc6 *tc6,
+ struct kernel_ethtool_ts_info *info)
+{
+ if (!tc6->ptp_clock)
+ return ethtool_op_get_ts_info(tc6->netdev, info);
+
+ info->so_timestamping = SOF_TIMESTAMPING_RAW_HARDWARE |
+ SOF_TIMESTAMPING_TX_HARDWARE |
+ SOF_TIMESTAMPING_RX_HARDWARE;
+ info->phc_index = ptp_clock_index(tc6->ptp_clock);
+ info->tx_types = BIT(HWTSTAMP_TX_ON);
+ info->rx_filters = BIT(HWTSTAMP_FILTER_ALL);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(oa_tc6_get_ts_info);
+
+MODULE_DESCRIPTION("OPEN Alliance 10BASE‑T1x MAC‑PHY Serial Interface Lib");
+MODULE_AUTHOR("Selva Rajagopal <selvamani.rajagopal@onsemi.com>");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/oa_tc6.h b/include/linux/oa_tc6.h
index 39b80033dfa9..4047c22a366a 100644
--- a/include/linux/oa_tc6.h
+++ b/include/linux/oa_tc6.h
@@ -12,6 +12,7 @@
#include <linux/etherdevice.h>
#include <linux/spi/spi.h>
+#include <linux/ptp_clock_kernel.h>
/* PHY – Clause 45 registers memory map selector (MMS) as per table 6 in
* the OPEN Alliance specification.
@@ -36,4 +37,15 @@ int oa_tc6_read_registers(struct oa_tc6 *tc6, u32 address, u32 value[],
u8 length);
netdev_tx_t oa_tc6_start_xmit(struct oa_tc6 *tc6, struct sk_buff *skb);
int oa_tc6_zero_align_receive_frame_enable(struct oa_tc6 *tc6);
+int oa_tc6_ptp_register(struct oa_tc6 *tc6, struct ptp_clock_info *info);
+int oa_tc6_ioctl(struct oa_tc6 *tc6, struct ifreq *rq, int cmd);
+int oa_tc6_get_ts_info(struct oa_tc6 *tc6,
+ struct kernel_ethtool_ts_info *ts_info);
+void oa_tc6_hwtstamp_get(struct oa_tc6 *tc6,
+ struct kernel_hwtstamp_config *cfg);
+void oa_tc6_get_ts_stats(struct oa_tc6 *tc6,
+ struct ethtool_ts_stats *ts_stats);
+int oa_tc6_hwtstamp_set(struct oa_tc6 *tc6,
+ struct kernel_hwtstamp_config *cfg);
+void oa_tc6_ptp_unregister(struct oa_tc6 *tc6);
#endif /* _LINUX_OA_TC6_H */
--
2.43.0
^ permalink raw reply related
* [PATCH net-next v5 05/15] net: ethernet: oa_tc6: Move constant definitions to header file
From: Selvamani Rajagopal via B4 Relay @ 2026-06-14 17:00 UTC (permalink / raw)
To: Andrew Lunn, Piergiorgio Beruto, Heiner Kallweit, Russell King,
David S. Miller, Eric Dumazet, Jakub Kicinski, Paolo Abeni,
Andrew Lunn, Parthiban Veerasooran, Selva Rajagopal,
Richard Cochran, Rob Herring, Krzysztof Kozlowski, Conor Dooley,
Simon Horman, Jonathan Corbet, Shuah Khan
Cc: netdev, linux-kernel, devicetree, linux-doc, Jerry Ray,
Selvamani Rajagopal
In-Reply-To: <20260614-s2500-mac-phy-support-v5-0-89874b72f725@onsemi.com>
From: Selvamani Rajagopal <Selvamani.Rajagopal@onsemi.com>
To help other source files within the module share the
constant definitions, they are moved to a header file.
The memory map selector(MMS) values that are defined in
in Table 6 of OPEN Alliance 10BASE-T1x Serial Interface
specification and currently used are added.
Signed-off-by: Selvamani Rajagopal <Selvamani.Rajagopal@onsemi.com>
---
changes in v5
- No change
changes in v4
- Added MMS values 1 and 12, which are used now
changes in v3
- Moved constant definitions from the source to newly created
header file for other sources in the directory to share.
- Standard specific defines are moved to Linux common header file
- First patch
---
drivers/net/ethernet/oa_tc6/oa_tc6.c | 145 +------------------------
drivers/net/ethernet/oa_tc6/oa_tc6_std_def.h | 157 +++++++++++++++++++++++++++
include/linux/oa_tc6.h | 15 +++
3 files changed, 173 insertions(+), 144 deletions(-)
diff --git a/drivers/net/ethernet/oa_tc6/oa_tc6.c b/drivers/net/ethernet/oa_tc6/oa_tc6.c
index 91a906a7918a..c7d70d37ba53 100644
--- a/drivers/net/ethernet/oa_tc6/oa_tc6.c
+++ b/drivers/net/ethernet/oa_tc6/oa_tc6.c
@@ -11,150 +11,7 @@
#include <linux/phy.h>
#include <linux/oa_tc6.h>
-/* OPEN Alliance TC6 registers */
-/* Standard Capabilities Register */
-#define OA_TC6_REG_STDCAP 0x0002
-#define STDCAP_DIRECT_PHY_REG_ACCESS BIT(8)
-
-/* Reset Control and Status Register */
-#define OA_TC6_REG_RESET 0x0003
-#define RESET_SWRESET BIT(0) /* Software Reset */
-
-/* Configuration Register #0 */
-#define OA_TC6_REG_CONFIG0 0x0004
-#define CONFIG0_SYNC BIT(15)
-#define CONFIG0_ZARFE_ENABLE BIT(12)
-
-/* Status Register #0 */
-#define OA_TC6_REG_STATUS0 0x0008
-#define STATUS0_RESETC BIT(6) /* Reset Complete */
-#define STATUS0_HEADER_ERROR BIT(5)
-#define STATUS0_LOSS_OF_FRAME_ERROR BIT(4)
-#define STATUS0_RX_BUFFER_OVERFLOW_ERROR BIT(3)
-#define STATUS0_TX_PROTOCOL_ERROR BIT(0)
-
-/* Buffer Status Register */
-#define OA_TC6_REG_BUFFER_STATUS 0x000B
-#define BUFFER_STATUS_TX_CREDITS_AVAILABLE GENMASK(15, 8)
-#define BUFFER_STATUS_RX_CHUNKS_AVAILABLE GENMASK(7, 0)
-
-/* Interrupt Mask Register #0 */
-#define OA_TC6_REG_INT_MASK0 0x000C
-#define INT_MASK0_HEADER_ERR_MASK BIT(5)
-#define INT_MASK0_LOSS_OF_FRAME_ERR_MASK BIT(4)
-#define INT_MASK0_RX_BUFFER_OVERFLOW_ERR_MASK BIT(3)
-#define INT_MASK0_TX_PROTOCOL_ERR_MASK BIT(0)
-
-/* PHY Clause 22 registers base address and mask */
-#define OA_TC6_PHY_STD_REG_ADDR_BASE 0xFF00
-#define OA_TC6_PHY_STD_REG_ADDR_MASK 0x1F
-
-/* Control command header */
-#define OA_TC6_CTRL_HEADER_DATA_NOT_CTRL BIT(31)
-#define OA_TC6_CTRL_HEADER_WRITE_NOT_READ BIT(29)
-#define OA_TC6_CTRL_HEADER_MEM_MAP_SELECTOR GENMASK(27, 24)
-#define OA_TC6_CTRL_HEADER_ADDR GENMASK(23, 8)
-#define OA_TC6_CTRL_HEADER_LENGTH GENMASK(7, 1)
-#define OA_TC6_CTRL_HEADER_PARITY BIT(0)
-
-/* Data header */
-#define OA_TC6_DATA_HEADER_DATA_NOT_CTRL BIT(31)
-#define OA_TC6_DATA_HEADER_DATA_VALID BIT(21)
-#define OA_TC6_DATA_HEADER_START_VALID BIT(20)
-#define OA_TC6_DATA_HEADER_START_WORD_OFFSET GENMASK(19, 16)
-#define OA_TC6_DATA_HEADER_END_VALID BIT(14)
-#define OA_TC6_DATA_HEADER_END_BYTE_OFFSET GENMASK(13, 8)
-#define OA_TC6_DATA_HEADER_PARITY BIT(0)
-
-/* Data footer */
-#define OA_TC6_DATA_FOOTER_EXTENDED_STS BIT(31)
-#define OA_TC6_DATA_FOOTER_RXD_HEADER_BAD BIT(30)
-#define OA_TC6_DATA_FOOTER_CONFIG_SYNC BIT(29)
-#define OA_TC6_DATA_FOOTER_RX_CHUNKS GENMASK(28, 24)
-#define OA_TC6_DATA_FOOTER_DATA_VALID BIT(21)
-#define OA_TC6_DATA_FOOTER_START_VALID BIT(20)
-#define OA_TC6_DATA_FOOTER_START_WORD_OFFSET GENMASK(19, 16)
-#define OA_TC6_DATA_FOOTER_END_VALID BIT(14)
-#define OA_TC6_DATA_FOOTER_END_BYTE_OFFSET GENMASK(13, 8)
-#define OA_TC6_DATA_FOOTER_TX_CREDITS GENMASK(5, 1)
-
-/* PHY – Clause 45 registers memory map selector (MMS) as per table 6 in the
- * OPEN Alliance specification.
- */
-#define OA_TC6_PHY_C45_PCS_MMS2 2 /* MMD 3 */
-#define OA_TC6_PHY_C45_PMA_PMD_MMS3 3 /* MMD 1 */
-#define OA_TC6_PHY_C45_VS_PLCA_MMS4 4 /* MMD 31 */
-#define OA_TC6_PHY_C45_AUTO_NEG_MMS5 5 /* MMD 7 */
-#define OA_TC6_PHY_C45_POWER_UNIT_MMS6 6 /* MMD 13 */
-
-#define OA_TC6_CTRL_HEADER_SIZE 4
-#define OA_TC6_CTRL_REG_VALUE_SIZE 4
-#define OA_TC6_CTRL_IGNORED_SIZE 4
-#define OA_TC6_CTRL_MAX_REGISTERS 128
-#define OA_TC6_CTRL_SPI_BUF_SIZE (OA_TC6_CTRL_HEADER_SIZE +\
- (OA_TC6_CTRL_MAX_REGISTERS *\
- OA_TC6_CTRL_REG_VALUE_SIZE) +\
- OA_TC6_CTRL_IGNORED_SIZE)
-#define OA_TC6_CHUNK_PAYLOAD_SIZE 64
-#define OA_TC6_DATA_HEADER_SIZE 4
-#define OA_TC6_CHUNK_SIZE (OA_TC6_DATA_HEADER_SIZE +\
- OA_TC6_CHUNK_PAYLOAD_SIZE)
-#define OA_TC6_MAX_TX_CHUNKS 48
-#define OA_TC6_SPI_DATA_BUF_SIZE (OA_TC6_MAX_TX_CHUNKS *\
- OA_TC6_CHUNK_SIZE)
-#define STATUS0_RESETC_POLL_DELAY 1000
-#define STATUS0_RESETC_POLL_TIMEOUT 1000000
-
-/* Internal structure for MAC-PHY drivers */
-struct oa_tc6 {
- struct device *dev;
- struct net_device *netdev;
- struct phy_device *phydev;
- struct mii_bus *mdiobus;
- struct spi_device *spi;
- struct mutex spi_ctrl_lock; /* Protects spi control transfer */
- spinlock_t tx_skb_lock; /* Protects tx skb handling */
- void *spi_ctrl_tx_buf;
- void *spi_ctrl_rx_buf;
- void *spi_data_tx_buf;
- void *spi_data_rx_buf;
- struct sk_buff *ongoing_tx_skb;
- struct sk_buff *waiting_tx_skb;
- struct sk_buff *rx_skb;
- struct task_struct *spi_thread;
- wait_queue_head_t spi_wq;
- u16 tx_skb_offset;
- u16 spi_data_tx_buf_offset;
- u16 tx_credits;
- u8 rx_chunks_available;
- bool rx_buf_overflow;
- bool int_flag;
-};
-
-enum oa_tc6_header_type {
- OA_TC6_CTRL_HEADER,
- OA_TC6_DATA_HEADER,
-};
-
-enum oa_tc6_register_op {
- OA_TC6_CTRL_REG_READ = 0,
- OA_TC6_CTRL_REG_WRITE = 1,
-};
-
-enum oa_tc6_data_valid_info {
- OA_TC6_DATA_INVALID,
- OA_TC6_DATA_VALID,
-};
-
-enum oa_tc6_data_start_valid_info {
- OA_TC6_DATA_START_INVALID,
- OA_TC6_DATA_START_VALID,
-};
-
-enum oa_tc6_data_end_valid_info {
- OA_TC6_DATA_END_INVALID,
- OA_TC6_DATA_END_VALID,
-};
+#include "oa_tc6_std_def.h"
static int oa_tc6_spi_transfer(struct oa_tc6 *tc6,
enum oa_tc6_header_type header_type, u16 length)
diff --git a/drivers/net/ethernet/oa_tc6/oa_tc6_std_def.h b/drivers/net/ethernet/oa_tc6/oa_tc6_std_def.h
new file mode 100644
index 000000000000..2d8e28fb46fc
--- /dev/null
+++ b/drivers/net/ethernet/oa_tc6/oa_tc6_std_def.h
@@ -0,0 +1,157 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Register and driver related definitions to support
+ * OPEN Alliance 10BASE‑T1x MAC‑PHY Serial Interface framework.
+ *
+ * Author: Selva Rajagopal <selvamani.rajagopal@onsemi.com>
+ */
+
+#ifndef OA_TC6_STD_DEF_H
+#define OA_TC6_STD_DEF_H
+
+#include <linux/ptp_clock_kernel.h>
+#include <linux/net_tstamp.h>
+#include <linux/netdevice.h>
+#include <linux/spi/spi.h>
+#include <linux/skbuff.h>
+#include <linux/sched.h>
+#include <linux/wait.h>
+#include <linux/phy.h>
+
+/* OPEN Alliance TC6 registers */
+/* Standard Capabilities Register */
+#define OA_TC6_REG_STDCAP 0x0002
+#define STDCAP_DIRECT_PHY_REG_ACCESS BIT(8)
+
+/* Reset Control and Status Register */
+#define OA_TC6_REG_RESET 0x0003
+#define RESET_SWRESET BIT(0) /* Software Reset */
+
+/* Configuration Register #0 */
+#define OA_TC6_REG_CONFIG0 0x0004
+#define CONFIG0_SYNC BIT(15)
+#define CONFIG0_ZARFE_ENABLE BIT(12)
+
+/* Status Register #0 */
+#define OA_TC6_REG_STATUS0 0x0008
+#define STATUS0_RESETC BIT(6) /* Reset Complete */
+#define STATUS0_HEADER_ERROR BIT(5)
+#define STATUS0_LOSS_OF_FRAME_ERROR BIT(4)
+#define STATUS0_RX_BUFFER_OVERFLOW_ERROR BIT(3)
+#define STATUS0_TX_PROTOCOL_ERROR BIT(0)
+
+/* Buffer Status Register */
+#define OA_TC6_REG_BUFFER_STATUS 0x000B
+#define BUFFER_STATUS_TX_CREDITS_AVAILABLE GENMASK(15, 8)
+#define BUFFER_STATUS_RX_CHUNKS_AVAILABLE GENMASK(7, 0)
+
+/* Interrupt Mask Register #0 */
+#define OA_TC6_REG_INT_MASK0 0x000C
+#define INT_MASK0_HEADER_ERR_MASK BIT(5)
+#define INT_MASK0_LOSS_OF_FRAME_ERR_MASK BIT(4)
+#define INT_MASK0_RX_BUFFER_OVERFLOW_ERR_MASK BIT(3)
+#define INT_MASK0_TX_PROTOCOL_ERR_MASK BIT(0)
+
+/* PHY Clause 22 registers base address and mask */
+#define OA_TC6_PHY_STD_REG_ADDR_BASE 0xFF00
+#define OA_TC6_PHY_STD_REG_ADDR_MASK 0x1F
+
+/* Control command header */
+#define OA_TC6_CTRL_HEADER_DATA_NOT_CTRL BIT(31)
+#define OA_TC6_CTRL_HEADER_WRITE_NOT_READ BIT(29)
+#define OA_TC6_CTRL_HEADER_MEM_MAP_SELECTOR GENMASK(27, 24)
+#define OA_TC6_CTRL_HEADER_ADDR GENMASK(23, 8)
+#define OA_TC6_CTRL_HEADER_LENGTH GENMASK(7, 1)
+#define OA_TC6_CTRL_HEADER_PARITY BIT(0)
+
+/* Data header */
+#define OA_TC6_DATA_HEADER_DATA_NOT_CTRL BIT(31)
+#define OA_TC6_DATA_HEADER_DATA_VALID BIT(21)
+#define OA_TC6_DATA_HEADER_START_VALID BIT(20)
+#define OA_TC6_DATA_HEADER_START_WORD_OFFSET GENMASK(19, 16)
+#define OA_TC6_DATA_HEADER_END_VALID BIT(14)
+#define OA_TC6_DATA_HEADER_END_BYTE_OFFSET GENMASK(13, 8)
+#define OA_TC6_DATA_HEADER_PARITY BIT(0)
+
+/* Data footer */
+#define OA_TC6_DATA_FOOTER_EXTENDED_STS BIT(31)
+#define OA_TC6_DATA_FOOTER_RXD_HEADER_BAD BIT(30)
+#define OA_TC6_DATA_FOOTER_CONFIG_SYNC BIT(29)
+#define OA_TC6_DATA_FOOTER_RX_CHUNKS GENMASK(28, 24)
+#define OA_TC6_DATA_FOOTER_DATA_VALID BIT(21)
+#define OA_TC6_DATA_FOOTER_START_VALID BIT(20)
+#define OA_TC6_DATA_FOOTER_START_WORD_OFFSET GENMASK(19, 16)
+#define OA_TC6_DATA_FOOTER_END_VALID BIT(14)
+#define OA_TC6_DATA_FOOTER_END_BYTE_OFFSET GENMASK(13, 8)
+#define OA_TC6_DATA_FOOTER_TX_CREDITS GENMASK(5, 1)
+
+#define OA_TC6_CTRL_HEADER_SIZE 4
+#define OA_TC6_CTRL_REG_VALUE_SIZE 4
+#define OA_TC6_CTRL_IGNORED_SIZE 4
+#define OA_TC6_CTRL_MAX_REGISTERS 128
+#define OA_TC6_CTRL_SPI_BUF_SIZE (OA_TC6_CTRL_HEADER_SIZE +\
+ (OA_TC6_CTRL_MAX_REGISTERS *\
+ OA_TC6_CTRL_REG_VALUE_SIZE) +\
+ OA_TC6_CTRL_IGNORED_SIZE)
+#define OA_TC6_CHUNK_PAYLOAD_SIZE 64
+#define OA_TC6_DATA_HEADER_SIZE 4
+#define OA_TC6_CHUNK_SIZE (OA_TC6_DATA_HEADER_SIZE +\
+ OA_TC6_CHUNK_PAYLOAD_SIZE)
+#define OA_TC6_MAX_TX_CHUNKS 48
+#define OA_TC6_SPI_DATA_BUF_SIZE (OA_TC6_MAX_TX_CHUNKS *\
+ OA_TC6_CHUNK_SIZE)
+#define STATUS0_RESETC_POLL_DELAY 1000
+#define STATUS0_RESETC_POLL_TIMEOUT 1000000
+
+/* Internal structure for MAC-PHY drivers */
+struct oa_tc6 {
+ struct device *dev;
+ struct net_device *netdev;
+ struct phy_device *phydev;
+ struct mii_bus *mdiobus;
+ struct spi_device *spi;
+ struct mutex spi_ctrl_lock; /* Protects spi control transfer */
+ spinlock_t tx_skb_lock; /* Protects tx skb handling */
+ void *spi_ctrl_tx_buf;
+ void *spi_ctrl_rx_buf;
+ void *spi_data_tx_buf;
+ void *spi_data_rx_buf;
+ struct sk_buff *ongoing_tx_skb;
+ struct sk_buff *waiting_tx_skb;
+ struct sk_buff *rx_skb;
+ struct task_struct *spi_thread;
+ wait_queue_head_t spi_wq;
+ u16 tx_skb_offset;
+ u16 spi_data_tx_buf_offset;
+ u16 tx_credits;
+ u8 rx_chunks_available;
+ bool rx_buf_overflow;
+ bool int_flag;
+};
+
+enum oa_tc6_header_type {
+ OA_TC6_CTRL_HEADER,
+ OA_TC6_DATA_HEADER,
+};
+
+enum oa_tc6_register_op {
+ OA_TC6_CTRL_REG_READ = 0,
+ OA_TC6_CTRL_REG_WRITE = 1,
+};
+
+enum oa_tc6_data_valid_info {
+ OA_TC6_DATA_INVALID,
+ OA_TC6_DATA_VALID,
+};
+
+enum oa_tc6_data_start_valid_info {
+ OA_TC6_DATA_START_INVALID,
+ OA_TC6_DATA_START_VALID,
+};
+
+enum oa_tc6_data_end_valid_info {
+ OA_TC6_DATA_END_INVALID,
+ OA_TC6_DATA_END_VALID,
+};
+#endif /* OA_TC6_STD_DEF_H */
+
diff --git a/include/linux/oa_tc6.h b/include/linux/oa_tc6.h
index 15f58e3c56c7..39b80033dfa9 100644
--- a/include/linux/oa_tc6.h
+++ b/include/linux/oa_tc6.h
@@ -7,9 +7,23 @@
* Author: Parthiban Veerasooran <parthiban.veerasooran@microchip.com>
*/
+#ifndef _LINUX_OA_TC6_H
+#define _LINUX_OA_TC6_H
+
#include <linux/etherdevice.h>
#include <linux/spi/spi.h>
+/* PHY – Clause 45 registers memory map selector (MMS) as per table 6 in
+ * the OPEN Alliance specification.
+ */
+#define OA_TC6_PHY_C45_MAC_MMS1 1 /* No MMD */
+#define OA_TC6_PHY_C45_PCS_MMS2 2 /* MMD 3 */
+#define OA_TC6_PHY_C45_PMA_PMD_MMS3 3 /* MMD 1 */
+#define OA_TC6_PHY_C45_VS_PLCA_MMS4 4 /* MMD 31 */
+#define OA_TC6_PHY_C45_AUTO_NEG_MMS5 5 /* MMD 7 */
+#define OA_TC6_PHY_C45_POWER_UNIT_MMS6 6 /* MMD 13 */
+#define OA_TC6_PHY_C45_VS_MMS12 12 /* for vendors */
+
struct oa_tc6;
struct oa_tc6 *oa_tc6_init(struct spi_device *spi, struct net_device *netdev);
@@ -22,3 +36,4 @@ int oa_tc6_read_registers(struct oa_tc6 *tc6, u32 address, u32 value[],
u8 length);
netdev_tx_t oa_tc6_start_xmit(struct oa_tc6 *tc6, struct sk_buff *skb);
int oa_tc6_zero_align_receive_frame_enable(struct oa_tc6 *tc6);
+#endif /* _LINUX_OA_TC6_H */
--
2.43.0
^ permalink raw reply related
* [PATCH net-next v5 08/15] net: ethernet: oa_tc6: read, write interface with MMS option
From: Selvamani Rajagopal via B4 Relay @ 2026-06-14 17:00 UTC (permalink / raw)
To: Andrew Lunn, Piergiorgio Beruto, Heiner Kallweit, Russell King,
David S. Miller, Eric Dumazet, Jakub Kicinski, Paolo Abeni,
Andrew Lunn, Parthiban Veerasooran, Selva Rajagopal,
Richard Cochran, Rob Herring, Krzysztof Kozlowski, Conor Dooley,
Simon Horman, Jonathan Corbet, Shuah Khan
Cc: netdev, linux-kernel, devicetree, linux-doc, Jerry Ray,
Selvamani Rajagopal
In-Reply-To: <20260614-s2500-mac-phy-support-v5-0-89874b72f725@onsemi.com>
From: Selvamani Rajagopal <Selvamani.Rajagopal@onsemi.com>
Vendors are allowed to use any memory map selector that
is between 10 and 15.
Current read/write API interface expects register address with
the value of MMS (memory map selector) embedded in it.
This requires vendors to encoding the address whenever the call
to read/write register is made. To avoid this extra step, and
to bring consistency in usage of the API by different vendors,
new APIs have been added to write and read registers with
MMS as one of the parameters.
Signed-off-by: Selvamani Rajagopal <Selvamani.Rajagopal@onsemi.com>
---
changes in v5
- No change
changes in v4
- New API added to take MMS as a parameter to avoid need for
read/write calls to encode MMS to the address.
- first patch
---
drivers/net/ethernet/microchip/lan865x/lan865x.c | 61 +++++++++------
drivers/net/ethernet/oa_tc6/oa_tc6.c | 97 +++++++++++++++++++++---
include/linux/oa_tc6.h | 8 ++
3 files changed, 131 insertions(+), 35 deletions(-)
diff --git a/drivers/net/ethernet/microchip/lan865x/lan865x.c b/drivers/net/ethernet/microchip/lan865x/lan865x.c
index 0277d9737369..3b555ee69804 100644
--- a/drivers/net/ethernet/microchip/lan865x/lan865x.c
+++ b/drivers/net/ethernet/microchip/lan865x/lan865x.c
@@ -13,27 +13,27 @@
#define DRV_NAME "lan8650"
/* MAC Network Control Register */
-#define LAN865X_REG_MAC_NET_CTL 0x00010000
+#define LAN865X_REG_MAC_NET_CTL 0x0
#define MAC_NET_CTL_TXEN BIT(3) /* Transmit Enable */
#define MAC_NET_CTL_RXEN BIT(2) /* Receive Enable */
/* MAC Network Configuration Reg */
-#define LAN865X_REG_MAC_NET_CFG 0x00010001
+#define LAN865X_REG_MAC_NET_CFG 0x1
#define MAC_NET_CFG_PROMISCUOUS_MODE BIT(4)
#define MAC_NET_CFG_MULTICAST_MODE BIT(6)
#define MAC_NET_CFG_UNICAST_MODE BIT(7)
/* MAC Hash Register Bottom */
-#define LAN865X_REG_MAC_L_HASH 0x00010020
+#define LAN865X_REG_MAC_L_HASH 0x20
/* MAC Hash Register Top */
-#define LAN865X_REG_MAC_H_HASH 0x00010021
+#define LAN865X_REG_MAC_H_HASH 0x21
/* MAC Specific Addr 1 Bottom Reg */
-#define LAN865X_REG_MAC_L_SADDR1 0x00010022
+#define LAN865X_REG_MAC_L_SADDR1 0x22
/* MAC Specific Addr 1 Top Reg */
-#define LAN865X_REG_MAC_H_SADDR1 0x00010023
+#define LAN865X_REG_MAC_H_SADDR1 0x23
/* MAC TSU Timer Increment Register */
-#define LAN865X_REG_MAC_TSU_TIMER_INCR 0x00010077
+#define LAN865X_REG_MAC_TSU_TIMER_INCR 0x77
#define MAC_TSU_TIMER_INCR_COUNT_NANOSECONDS 0x0028
struct lan865x_priv {
@@ -49,7 +49,8 @@ static int lan865x_set_hw_macaddr_low_bytes(struct oa_tc6 *tc6, const u8 *mac)
regval = (mac[3] << 24) | (mac[2] << 16) | (mac[1] << 8) | mac[0];
- return oa_tc6_write_register(tc6, LAN865X_REG_MAC_L_SADDR1, regval);
+ return oa_tc6_write_register_mms(tc6, LAN865X_REG_MAC_L_SADDR1,
+ OA_TC6_PHY_C45_MAC_MMS1, regval);
}
static int lan865x_set_hw_macaddr(struct lan865x_priv *priv, const u8 *mac)
@@ -65,8 +66,8 @@ static int lan865x_set_hw_macaddr(struct lan865x_priv *priv, const u8 *mac)
/* Prepare and configure MAC address high bytes */
regval = (mac[5] << 8) | mac[4];
- ret = oa_tc6_write_register(priv->tc6, LAN865X_REG_MAC_H_SADDR1,
- regval);
+ ret = oa_tc6_write_register_mms(priv->tc6, LAN865X_REG_MAC_H_SADDR1,
+ OA_TC6_PHY_C45_MAC_MMS1, regval);
if (!ret)
return 0;
@@ -146,14 +147,16 @@ static int lan865x_set_specific_multicast_addr(struct lan865x_priv *priv)
}
/* Enabling specific multicast addresses */
- ret = oa_tc6_write_register(priv->tc6, LAN865X_REG_MAC_H_HASH, hash_hi);
+ ret = oa_tc6_write_register_mms(priv->tc6, LAN865X_REG_MAC_H_HASH,
+ OA_TC6_PHY_C45_MAC_MMS1, hash_hi);
if (ret) {
netdev_err(priv->netdev, "Failed to write reg_hashh: %d\n",
ret);
return ret;
}
- ret = oa_tc6_write_register(priv->tc6, LAN865X_REG_MAC_L_HASH, hash_lo);
+ ret = oa_tc6_write_register_mms(priv->tc6, LAN865X_REG_MAC_L_HASH,
+ OA_TC6_PHY_C45_MAC_MMS1, hash_lo);
if (ret)
netdev_err(priv->netdev, "Failed to write reg_hashl: %d\n",
ret);
@@ -166,16 +169,16 @@ static int lan865x_set_all_multicast_addr(struct lan865x_priv *priv)
int ret;
/* Enabling all multicast addresses */
- ret = oa_tc6_write_register(priv->tc6, LAN865X_REG_MAC_H_HASH,
- 0xffffffff);
+ ret = oa_tc6_write_register_mms(priv->tc6, LAN865X_REG_MAC_H_HASH,
+ OA_TC6_PHY_C45_MAC_MMS1, 0xffffffff);
if (ret) {
netdev_err(priv->netdev, "Failed to write reg_hashh: %d\n",
ret);
return ret;
}
- ret = oa_tc6_write_register(priv->tc6, LAN865X_REG_MAC_L_HASH,
- 0xffffffff);
+ ret = oa_tc6_write_register_mms(priv->tc6, LAN865X_REG_MAC_L_HASH,
+ OA_TC6_PHY_C45_MAC_MMS1, 0xffffffff);
if (ret)
netdev_err(priv->netdev, "Failed to write reg_hashl: %d\n",
ret);
@@ -187,14 +190,16 @@ static int lan865x_clear_all_multicast_addr(struct lan865x_priv *priv)
{
int ret;
- ret = oa_tc6_write_register(priv->tc6, LAN865X_REG_MAC_H_HASH, 0);
+ ret = oa_tc6_write_register_mms(priv->tc6, LAN865X_REG_MAC_H_HASH,
+ OA_TC6_PHY_C45_MAC_MMS1, 0);
if (ret) {
netdev_err(priv->netdev, "Failed to write reg_hashh: %d\n",
ret);
return ret;
}
- ret = oa_tc6_write_register(priv->tc6, LAN865X_REG_MAC_L_HASH, 0);
+ ret = oa_tc6_write_register_mms(priv->tc6, LAN865X_REG_MAC_L_HASH,
+ OA_TC6_PHY_C45_MAC_MMS1, 0);
if (ret)
netdev_err(priv->netdev, "Failed to write reg_hashl: %d\n",
ret);
@@ -235,7 +240,8 @@ static void lan865x_multicast_work_handler(struct work_struct *work)
if (lan865x_clear_all_multicast_addr(priv))
return;
}
- ret = oa_tc6_write_register(priv->tc6, LAN865X_REG_MAC_NET_CFG, regval);
+ ret = oa_tc6_write_register_mms(priv->tc6, LAN865X_REG_MAC_NET_CFG,
+ OA_TC6_PHY_C45_MAC_MMS1, regval);
if (ret)
netdev_err(priv->netdev, "Failed to enable promiscuous/multicast/normal mode: %d\n",
ret);
@@ -260,12 +266,14 @@ static int lan865x_hw_disable(struct lan865x_priv *priv)
{
u32 regval;
- if (oa_tc6_read_register(priv->tc6, LAN865X_REG_MAC_NET_CTL, ®val))
+ if (oa_tc6_read_register_mms(priv->tc6, LAN865X_REG_MAC_NET_CTL,
+ OA_TC6_PHY_C45_MAC_MMS1, ®val))
return -ENODEV;
regval &= ~(MAC_NET_CTL_TXEN | MAC_NET_CTL_RXEN);
- if (oa_tc6_write_register(priv->tc6, LAN865X_REG_MAC_NET_CTL, regval))
+ if (oa_tc6_write_register_mms(priv->tc6, LAN865X_REG_MAC_NET_CTL,
+ OA_TC6_PHY_C45_MAC_MMS1, regval))
return -ENODEV;
return 0;
@@ -291,12 +299,14 @@ static int lan865x_hw_enable(struct lan865x_priv *priv)
{
u32 regval;
- if (oa_tc6_read_register(priv->tc6, LAN865X_REG_MAC_NET_CTL, ®val))
+ if (oa_tc6_read_register_mms(priv->tc6, LAN865X_REG_MAC_NET_CTL,
+ OA_TC6_PHY_C45_MAC_MMS1, ®val))
return -ENODEV;
regval |= MAC_NET_CTL_TXEN | MAC_NET_CTL_RXEN;
- if (oa_tc6_write_register(priv->tc6, LAN865X_REG_MAC_NET_CTL, regval))
+ if (oa_tc6_write_register_mms(priv->tc6, LAN865X_REG_MAC_NET_CTL,
+ OA_TC6_PHY_C45_MAC_MMS1, regval))
return -ENODEV;
return 0;
@@ -359,8 +369,9 @@ static int lan865x_probe(struct spi_device *spi)
* stamping at the end of the Start of Frame Delimiter (SFD) and set the
* Timer Increment reg to 40 ns to be used as a 25 MHz internal clock.
*/
- ret = oa_tc6_write_register(priv->tc6, LAN865X_REG_MAC_TSU_TIMER_INCR,
- MAC_TSU_TIMER_INCR_COUNT_NANOSECONDS);
+ ret = oa_tc6_write_register_mms(priv->tc6, LAN865X_REG_MAC_TSU_TIMER_INCR,
+ OA_TC6_PHY_C45_MAC_MMS1,
+ MAC_TSU_TIMER_INCR_COUNT_NANOSECONDS);
if (ret) {
dev_err(&spi->dev, "Failed to config TSU Timer Incr reg: %d\n",
ret);
diff --git a/drivers/net/ethernet/oa_tc6/oa_tc6.c b/drivers/net/ethernet/oa_tc6/oa_tc6.c
index fab7cb84df71..129263f3be31 100644
--- a/drivers/net/ethernet/oa_tc6/oa_tc6.c
+++ b/drivers/net/ethernet/oa_tc6/oa_tc6.c
@@ -378,6 +378,83 @@ int oa_tc6_read_register(struct oa_tc6 *tc6, u32 address, u32 *value)
}
EXPORT_SYMBOL_GPL(oa_tc6_read_register);
+/**
+ * oa_tc6_read_registers_mms - function for reading multiple consecutive
+ * registers for the given address, memory map selector pair.
+ * @tc6: oa_tc6 struct.
+ * @address: address of the first register to be read in the MAC-PHY.
+ * @mms: Memory map selector for the registers to be read.
+ * @value: values to be read from the starting register address @address.
+ * @length: number of consecutive registers to be read from @address.
+ *
+ * Return: 0 on success otherwise failed.
+ */
+int oa_tc6_read_registers_mms(struct oa_tc6 *tc6, u16 address, u16 mms,
+ u32 value[], u8 length)
+{
+ u32 mms_addr = (u32)mms << 16 | (u32)address;
+
+ return oa_tc6_read_registers(tc6, mms_addr, value, length);
+}
+EXPORT_SYMBOL_GPL(oa_tc6_read_registers_mms);
+
+/**
+ * oa_tc6_read_register_mms - function for reading a MAC-PHY register
+ * for the given address, memory map selector pair.
+ * @tc6: oa_tc6 struct.
+ * @address: register address of the MAC-PHY to be read.
+ * @mms: Memory Map Selector for the given address
+ * @value: value read from the @address register address of the MAC-PHY.
+ *
+ * Return: 0 on success otherwise failed.
+ */
+int oa_tc6_read_register_mms(struct oa_tc6 *tc6, u16 address, u16 mms,
+ u32 *value)
+{
+ return oa_tc6_read_registers_mms(tc6, address, mms, value, 1);
+}
+EXPORT_SYMBOL_GPL(oa_tc6_read_register_mms);
+
+/**
+ * oa_tc6_write_registers_mms - function for writing multiple consecutive
+ * registers for the given address, memory map selector pair.
+ * @tc6: oa_tc6 struct.
+ * @address: address of the first register to be written in the MAC-PHY.
+ * @mms: memory map Selector for the given register.
+ * @value: values to be written from the starting register address @address.
+ * @length: number of consecutive registers to be written from @address.
+ *
+ * Maximum of 128 consecutive registers can be written starting at @address.
+ *
+ * Return: 0 on success otherwise failed.
+ */
+int oa_tc6_write_registers_mms(struct oa_tc6 *tc6, u16 address, u16 mms,
+ u32 value[], u8 length)
+{
+ u32 mms_addr = (u32)mms << 16 | (u32)address;
+
+ return oa_tc6_write_registers(tc6, mms_addr, value, length);
+}
+EXPORT_SYMBOL_GPL(oa_tc6_write_registers_mms);
+
+/**
+ * oa_tc6_write_register_mms - function for writing a MAC-PHY register
+ * associated with the given memory map selector.
+ * @tc6: oa_tc6 struct.
+ * @address: register address of the MAC-PHY to be written.
+ * @mms: memory map selector for the given register.
+ * @value: value to be written in the @address register address of
+ * the MAC-PHY.
+ *
+ * Return: 0 on success otherwise failed.
+ */
+int oa_tc6_write_register_mms(struct oa_tc6 *tc6, u16 address, u16 mms,
+ u32 value)
+{
+ return oa_tc6_write_registers_mms(tc6, address, mms, &value, 1);
+}
+EXPORT_SYMBOL_GPL(oa_tc6_write_register_mms);
+
/**
* oa_tc6_write_registers - function for writing multiple consecutive registers.
* @tc6: oa_tc6 struct.
@@ -491,14 +568,14 @@ static int oa_tc6_mdiobus_read_c45(struct mii_bus *bus, int addr, int devnum,
int regnum)
{
struct oa_tc6 *tc6 = bus->priv;
+ int mms, ret;
u32 regval;
- int ret;
- ret = oa_tc6_get_phy_c45_mms(tc6, devnum);
- if (ret < 0)
- return ret;
+ mms = oa_tc6_get_phy_c45_mms(tc6, devnum);
+ if (mms < 0)
+ return mms;
- ret = oa_tc6_read_register(tc6, (ret << 16) | regnum, ®val);
+ ret = oa_tc6_read_register_mms(tc6, (u16)regnum, (u16)mms, ®val);
if (ret)
return ret;
@@ -509,13 +586,13 @@ static int oa_tc6_mdiobus_write_c45(struct mii_bus *bus, int addr, int devnum,
int regnum, u16 val)
{
struct oa_tc6 *tc6 = bus->priv;
- int ret;
+ int mms;
- ret = oa_tc6_get_phy_c45_mms(tc6, devnum);
- if (ret < 0)
- return ret;
+ mms = oa_tc6_get_phy_c45_mms(tc6, devnum);
+ if (mms < 0)
+ return mms;
- return oa_tc6_write_register(tc6, (ret << 16) | regnum, val);
+ return oa_tc6_write_register_mms(tc6, (u16)regnum, (u16)mms, val);
}
static int oa_tc6_mdiobus_register(struct oa_tc6 *tc6)
diff --git a/include/linux/oa_tc6.h b/include/linux/oa_tc6.h
index a89151267713..3d50971f0f5b 100644
--- a/include/linux/oa_tc6.h
+++ b/include/linux/oa_tc6.h
@@ -37,6 +37,14 @@ int oa_tc6_read_registers(struct oa_tc6 *tc6, u32 address, u32 value[],
u8 length);
netdev_tx_t oa_tc6_start_xmit(struct oa_tc6 *tc6, struct sk_buff *skb);
int oa_tc6_zero_align_receive_frame_enable(struct oa_tc6 *tc6);
+int oa_tc6_write_registers_mms(struct oa_tc6 *tc6, u16 address, u16 mms,
+ u32 value[], u8 length);
+int oa_tc6_write_register_mms(struct oa_tc6 *tc6, u16 address, u16 mms,
+ u32 value);
+int oa_tc6_read_registers_mms(struct oa_tc6 *tc6, u16 address, u16 mms,
+ u32 value[], u8 length);
+int oa_tc6_read_register_mms(struct oa_tc6 *tc6, u16 address, u16 mms,
+ u32 *value);
int oa_tc6_ptp_register(struct oa_tc6 *tc6, struct ptp_clock_info *info);
int oa_tc6_ioctl(struct oa_tc6 *tc6, struct ifreq *rq, int cmd);
int oa_tc6_get_ts_info(struct oa_tc6 *tc6,
--
2.43.0
^ permalink raw reply related
* [PATCH net-next v5 07/15] net: ethernet: oa_tc6: Support for vendor specific MMS
From: Selvamani Rajagopal via B4 Relay @ 2026-06-14 17:00 UTC (permalink / raw)
To: Andrew Lunn, Piergiorgio Beruto, Heiner Kallweit, Russell King,
David S. Miller, Eric Dumazet, Jakub Kicinski, Paolo Abeni,
Andrew Lunn, Parthiban Veerasooran, Selva Rajagopal,
Richard Cochran, Rob Herring, Krzysztof Kozlowski, Conor Dooley,
Simon Horman, Jonathan Corbet, Shuah Khan
Cc: netdev, linux-kernel, devicetree, linux-doc, Jerry Ray,
Selvamani Rajagopal
In-Reply-To: <20260614-s2500-mac-phy-support-v5-0-89874b72f725@onsemi.com>
From: Selvamani Rajagopal <Selvamani.Rajagopal@onsemi.com>
OPEN Alliance 10BASE-T1x Serial Interface specification, table 6
allows vendors to use any memory map select (MMS) value between
10 and 15. This new API interface enables vendor to map one of
thes MMS values to MDIO_MMD_VEND1.
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Selvamani Rajagopal <Selvamani.Rajagopal@onsemi.com>
---
changes in v5
- no change
changes in v4
- no change
changes in v3
- no change
changes in v2
- Moved the handling of vendor specific MMS mapping to separate patch
- new patch
---
drivers/net/ethernet/oa_tc6/oa_tc6.c | 21 ++++++++++++++++++---
include/linux/oa_tc6.h | 1 +
2 files changed, 19 insertions(+), 3 deletions(-)
diff --git a/drivers/net/ethernet/oa_tc6/oa_tc6.c b/drivers/net/ethernet/oa_tc6/oa_tc6.c
index 9410cecfdc2a..fab7cb84df71 100644
--- a/drivers/net/ethernet/oa_tc6/oa_tc6.c
+++ b/drivers/net/ethernet/oa_tc6/oa_tc6.c
@@ -202,6 +202,18 @@ int oa_tc6_ioctl(struct oa_tc6 *tc6, struct ifreq *rq, int cmd)
}
EXPORT_SYMBOL_GPL(oa_tc6_ioctl);
+/**
+ * oa_tc6_set_vend1_mms - Add vendor specific MDIO_MMD to OA TC6 MMS
+ * mapper value.
+ * @tc6: oa_tc6 struct.
+ * @mms: vendor defined MMS value for VEND1 mdio device.
+ */
+void oa_tc6_set_vend1_mms(struct oa_tc6 *tc6, int mms)
+{
+ tc6->vend1_mms = mms;
+}
+EXPORT_SYMBOL_GPL(oa_tc6_set_vend1_mms);
+
static __be32 oa_tc6_prepare_ctrl_header(u32 addr, u8 length,
enum oa_tc6_register_op reg_op)
{
@@ -455,7 +467,7 @@ static int oa_tc6_mdiobus_write(struct mii_bus *bus, int addr, int regnum,
val);
}
-static int oa_tc6_get_phy_c45_mms(int devnum)
+static int oa_tc6_get_phy_c45_mms(struct oa_tc6 *tc6, int devnum)
{
switch (devnum) {
case MDIO_MMD_PCS:
@@ -468,6 +480,8 @@ static int oa_tc6_get_phy_c45_mms(int devnum)
return OA_TC6_PHY_C45_AUTO_NEG_MMS5;
case MDIO_MMD_POWER_UNIT:
return OA_TC6_PHY_C45_POWER_UNIT_MMS6;
+ case MDIO_MMD_VEND1:
+ return tc6->vend1_mms;
default:
return -EOPNOTSUPP;
}
@@ -480,7 +494,7 @@ static int oa_tc6_mdiobus_read_c45(struct mii_bus *bus, int addr, int devnum,
u32 regval;
int ret;
- ret = oa_tc6_get_phy_c45_mms(devnum);
+ ret = oa_tc6_get_phy_c45_mms(tc6, devnum);
if (ret < 0)
return ret;
@@ -497,7 +511,7 @@ static int oa_tc6_mdiobus_write_c45(struct mii_bus *bus, int addr, int devnum,
struct oa_tc6 *tc6 = bus->priv;
int ret;
- ret = oa_tc6_get_phy_c45_mms(devnum);
+ ret = oa_tc6_get_phy_c45_mms(tc6, devnum);
if (ret < 0)
return ret;
@@ -1281,6 +1295,7 @@ struct oa_tc6 *oa_tc6_init(struct spi_device *spi, struct net_device *netdev)
SET_NETDEV_DEV(netdev, &spi->dev);
mutex_init(&tc6->spi_ctrl_lock);
spin_lock_init(&tc6->tx_skb_lock);
+ tc6->vend1_mms = -EOPNOTSUPP;
tc6->tx_ts_idx = OA_TC6_TTSCA_REG_ID;
INIT_LIST_HEAD(&tc6->tx_ts_skb_q);
diff --git a/include/linux/oa_tc6.h b/include/linux/oa_tc6.h
index 4047c22a366a..a89151267713 100644
--- a/include/linux/oa_tc6.h
+++ b/include/linux/oa_tc6.h
@@ -47,5 +47,6 @@ void oa_tc6_get_ts_stats(struct oa_tc6 *tc6,
struct ethtool_ts_stats *ts_stats);
int oa_tc6_hwtstamp_set(struct oa_tc6 *tc6,
struct kernel_hwtstamp_config *cfg);
+void oa_tc6_set_vend1_mms(struct oa_tc6 *tc6, int mms);
void oa_tc6_ptp_unregister(struct oa_tc6 *tc6);
#endif /* _LINUX_OA_TC6_H */
--
2.43.0
^ permalink raw reply related
* [PATCH net-next v5 10/15] net: phy: ncn26000: Enable enhanced noise immunity
From: Selvamani Rajagopal via B4 Relay @ 2026-06-14 17:00 UTC (permalink / raw)
To: Andrew Lunn, Piergiorgio Beruto, Heiner Kallweit, Russell King,
David S. Miller, Eric Dumazet, Jakub Kicinski, Paolo Abeni,
Andrew Lunn, Parthiban Veerasooran, Selva Rajagopal,
Richard Cochran, Rob Herring, Krzysztof Kozlowski, Conor Dooley,
Simon Horman, Jonathan Corbet, Shuah Khan
Cc: netdev, linux-kernel, devicetree, linux-doc, Jerry Ray,
Selvamani Rajagopal
In-Reply-To: <20260614-s2500-mac-phy-support-v5-0-89874b72f725@onsemi.com>
From: Selvamani Rajagopal <Selvamani.Rajagopal@onsemi.com>
By setting ENI bit, noise immunity is improved and it is
specifically meant for PLCA enabled nodes.
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Selvamani Rajagopal <Selvamani.Rajagopal@onsemi.com>
---
changes in v5
- No changes
changes in v4
- No changes
changes in v3
- Moved as a separate patch
---
drivers/net/phy/ncn26000.c | 26 ++++++++++++++++++++++++--
1 file changed, 24 insertions(+), 2 deletions(-)
diff --git a/drivers/net/phy/ncn26000.c b/drivers/net/phy/ncn26000.c
index 2c8601c3f94a..c3a34b2c524d 100644
--- a/drivers/net/phy/ncn26000.c
+++ b/drivers/net/phy/ncn26000.c
@@ -36,6 +36,10 @@
#define TO_TMR_DEFAULT 32
+#define NCN26000_REG_PHYCFG1 0x8001
+#define NCN26000_PHYCFG1_ENI BIT(7)
+#define NCN26000_PHYCFG1_ENI_MASK BIT(7)
+
static int ncn26000_config_init(struct phy_device *phydev)
{
int ret = 0;
@@ -106,6 +110,24 @@ static int ncn26000_read_status(struct phy_device *phydev)
return 0;
}
+/* Intercept PLCA enable/disable request to
+ * set the proprietary, ENI mode accordingly
+ */
+static int ncn26000_c45_plca_set_cfg(struct phy_device *phydev,
+ const struct phy_plca_cfg *plca_cfg)
+{
+ int ret = genphy_c45_plca_set_cfg(phydev, plca_cfg);
+ u16 eni_cfg = 0;
+
+ if (ret || plca_cfg->enabled < 0)
+ return ret;
+
+ eni_cfg = (plca_cfg->enabled) ? NCN26000_PHYCFG1_ENI : 0;
+ return phy_modify_mmd(phydev, MDIO_MMD_VEND2,
+ NCN26000_REG_PHYCFG1,
+ NCN26000_PHYCFG1_ENI_MASK, eni_cfg);
+}
+
static irqreturn_t ncn26000_handle_interrupt(struct phy_device *phydev)
{
int ret;
@@ -156,7 +178,7 @@ static struct phy_driver ncn26000_driver[] = {
.config_aneg = ncn26000_config_aneg,
.read_status = ncn26000_read_status,
.handle_interrupt = ncn26000_handle_interrupt,
- .set_plca_cfg = genphy_c45_plca_set_cfg,
+ .set_plca_cfg = ncn26000_c45_plca_set_cfg,
.get_plca_cfg = genphy_c45_plca_get_cfg,
.get_plca_status = genphy_c45_plca_get_status,
.soft_reset = genphy_soft_reset,
@@ -177,7 +199,7 @@ static struct phy_driver ncn26000_driver[] = {
.read_status = ncn26000_read_status,
.handle_interrupt = ncn26000_handle_interrupt,
.get_plca_cfg = genphy_c45_plca_get_cfg,
- .set_plca_cfg = genphy_c45_plca_set_cfg,
+ .set_plca_cfg = ncn26000_c45_plca_set_cfg,
.get_plca_status = genphy_c45_plca_get_status,
.soft_reset = genphy_soft_reset,
},
--
2.43.0
^ permalink raw reply related
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