On Fri, Jan 16, 2026 at 01:35:00PM +0000, Elif Topuz wrote:

Hi Cristian,

H Elif,

On 14/01/2026 11:46, Cristian Marussi wrote:

quoted

Add an alternative filesystem view for the discovered Data Events, where
the tree of DEs is laid out following the discovered topological order
instead of the existing flat layout.

Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
---
v1 --> v2
 - Use new FS API
 - Introduce new stlmfs_lookup_by_name helper
---
 .../firmware/arm_scmi/scmi_system_telemetry.c | 684 ++++++++++++++++++
 1 file changed, 684 insertions(+)

diff --git a/drivers/firmware/arm_scmi/scmi_system_telemetry.c b/drivers/firmware/arm_scmi/scmi_system_telemetry.c
index 721de615bec3..1221520356fd 100644
--- a/drivers/firmware/arm_scmi/scmi_system_telemetry.c
+++ b/drivers/firmware/arm_scmi/scmi_system_telemetry.c

@@ -174,6 +174,7 @@ struct scmi_tlm_inode {
  * @top_dentry: A reference to the top dentry for this instance.
  * @des_dentry: A reference to the DES dentry for this instance.
  * @grps_dentry: A reference to the groups dentry for this instance.
+ * @compo_dentry: A reference to the components dentry for this instance.
  * @info: A handy reference to this instance SCMI Telemetry info data.
  *
  */

@@ -188,6 +189,7 @@ struct scmi_tlm_instance {
 	struct dentry *top_dentry;
 	struct dentry *des_dentry;
 	struct dentry *grps_dentry;
+	struct dentry *compo_dentry;
 	const struct scmi_telemetry_info *info;
 };
 

@@ -196,6 +198,526 @@ static int scmi_telemetry_instance_register(struct super_block *sb,
 
 static LIST_HEAD(scmi_telemetry_instances);
 
+#define TYPES_ARRAY_SZ		256
+
+static const char *compo_types[TYPES_ARRAY_SZ] = {
+	"unspec",
+	"cpu",
+	"cluster",
+	"gpu",
+	"npu",
+	"interconnnect",
+	"mem_cntrl",
+	"l1_cache",
+	"l2_cache",
+	"l3_cache",
+	"ll_cache",
+	"sys_cache",
+	"disp_cntrl",
+	"ipu",
+	"chiplet",
+	"package",
+	"soc",
+	"system",
+	"smcu",
+	"accel",
+	"battery",
+	"charger",
+	"pmic",
+	"board",
+	"memory",
+	"periph",
+	"periph_subc",
+	"lid",
+	"display",
+	"res_29",
+	"res_30",
+	"res_31",
+	"res_32",
+	"res_33",
+	"res_34",
+	"res_35",
+	"res_36",
+	"res_37",
+	"res_38",
+	"res_39",
+	"res_40",
+	"res_41",
+	"res_42",
+	"res_43",
+	"res_44",
+	"res_45",
+	"res_46",
+	"res_47",
+	"res_48",
+	"res_49",
+	"res_50",
+	"res_51",
+	"res_52",
+	"res_53",
+	"res_54",
+	"res_55",
+	"res_56",
+	"res_57",
+	"res_58",
+	"res_59",
+	"res_60",
+	"res_61",
+	"res_62",
+	"res_63",
+	"res_64",
+	"res_65",
+	"res_66",
+	"res_67",
+	"res_68",
+	"res_69",
+	"res_70",
+	"res_71",
+	"res_72",
+	"res_73",
+	"res_74",
+	"res_75",
+	"res_76",
+	"res_77",
+	"res_78",
+	"res_79",
+	"res_80",
+	"res_81",
+	"res_82",
+	"res_83",
+	"res_84",
+	"res_85",
+	"res_86",
+	"res_87",
+	"res_88",
+	"res_89",
+	"res_90",
+	"res_91",
+	"res_92",
+	"res_93",
+	"res_94",
+	"res_95",
+	"res_96",
+	"res_97",
+	"res_98",
+	"res_99",
+	"res_100",
+	"res_101",
+	"res_102",
+	"res_103",
+	"res_104",
+	"res_105",
+	"res_106",
+	"res_107",
+	"res_108",
+	"res_109",
+	"res_110",
+	"res_111",
+	"res_112",
+	"res_113",
+	"res_114",
+	"res_115",
+	"res_116",
+	"res_117",
+	"res_118",
+	"res_119",
+	"res_120",
+	"res_121",
+	"res_122",
+	"res_123",
+	"res_124",
+	"res_125",
+	"res_126",
+	"res_127",
+	"res_128",
+	"res_129",
+	"res_130",
+	"res_131",
+	"res_132",
+	"res_133",
+	"res_134",
+	"res_135",
+	"res_136",
+	"res_137",
+	"res_138",
+	"res_139",
+	"res_140",
+	"res_141",
+	"res_142",
+	"res_143",
+	"res_144",
+	"res_145",
+	"res_146",
+	"res_147",
+	"res_148",
+	"res_149",
+	"res_150",
+	"res_151",
+	"res_152",
+	"res_153",
+	"res_154",
+	"res_155",
+	"res_156",
+	"res_157",
+	"res_158",
+	"res_159",
+	"res_160",
+	"res_161",
+	"res_162",
+	"res_163",
+	"res_164",
+	"res_165",
+	"res_166",
+	"res_167",
+	"res_168",
+	"res_169",
+	"res_170",
+	"res_171",
+	"res_172",
+	"res_173",
+	"res_174",
+	"res_175",
+	"res_176",
+	"res_177",
+	"res_178",
+	"res_179",
+	"res_180",
+	"res_181",
+	"res_182",
+	"res_183",
+	"res_184",
+	"res_185",
+	"res_186",
+	"res_187",
+	"res_188",
+	"res_189",
+	"res_190",
+	"res_191",
+	"res_192",
+	"res_193",
+	"res_194",
+	"res_195",
+	"res_196",
+	"res_197",
+	"res_198",
+	"res_199",
+	"res_200",
+	"res_201",
+	"res_202",
+	"res_203",
+	"res_204",
+	"res_205",
+	"res_206",
+	"res_207",
+	"res_208",
+	"res_209",
+	"res_210",
+	"res_211",
+	"res_212",
+	"res_213",
+	"res_214",
+	"res_215",
+	"res_216",
+	"res_217",
+	"res_218",
+	"res_219",
+	"res_220",
+	"res_221",
+	"res_222",
+	"res_223",
+	"oem_224",
+	"oem_225",
+	"oem_226",
+	"oem_227",
+	"oem_228",
+	"oem_229",
+	"oem_230",
+	"oem_231",
+	"oem_232",
+	"oem_233",
+	"oem_234",
+	"oem_235",
+	"oem_236",
+	"oem_237",
+	"oem_238",
+	"oem_239",
+	"oem_240",
+	"oem_241",
+	"oem_242",
+	"oem_243",
+	"oem_244",
+	"oem_245",
+	"oem_246",
+	"oem_247",
+	"oem_248",
+	"oem_249",
+	"oem_250",
+	"oem_251",
+	"oem_252",
+	"oem_253",
+	"oem_254",
+	"oem_255",
+};
+
+static const char *unit_types[TYPES_ARRAY_SZ] = {
+	"none",
+	"unspec",
+	"celsius",
+	"fahrenheit",
+	"kelvin",
+	"volts",
+	"amps",
+	"watts",
+	"joules",
+	"coulombs",
+	"va",
+	"nits",
+	"lumens",
+	"lux",
+	"candelas",
+	"kpa",
+	"psi",
+	"newtons",
+	"cfm",
+	"rpm",
+	"hertz",
+	"seconds",
+	"minutes",
+	"hours",
+	"days",
+	"weeks",
+	"mils",
+	"inches",
+	"feet",
+	"cubic_inches",
+	"cubic_feet",
+	"meters",
+	"cubic_centimeters",
+	"cubic_meters",
+	"liters",
+	"fluid_ounces",
+	"radians",
+	"steradians",
+	"revolutions",
+	"cycles",
+	"gravities",
+	"ounces",
+	"pounds",
+	"foot_pounds",
+	"ounce_inches",
+	"gauss",
+	"gilberts",
+	"henries",
+	"farads",
+	"ohms",
+	"siemens",
+	"moles",
+	"becquerels",
+	"ppm",
+	"decibels",
+	"dba",
+	"dbc",
+	"grays",
+	"sieverts",
+	"color_temp_kelvin",
+	"bits",
+	"bytes",
+	"words",
+	"dwords",
+	"qwords",
+	"percentage",
+	"pascals",
+	"counts",
+	"grams",
+	"newton_meters",
+	"hits",
+	"misses",
+	"retries",
+	"overruns",
+	"underruns",
+	"collisions",
+	"packets",
+	"messages",
+	"chars",
+	"errors",
+	"corrected_err",
+	"uncorrectable_err",
+	"square_mils",
+	"square_inches",
+	"square_feet",
+	"square_centimeters",
+	"square_meters",
+	"radians_per_secs",
+	"beats_per_minute",
+	"meters_per_secs_squared",
+	"meters_per_secs",
+	"cubic_meter_per_secs",
+	"millimeters_mercury",
+	"radians_per_secs_squared",
+	"state",
+	"bps",
+	"res_96",
+	"res_97",
+	"res_98",
+	"res_99",
+	"res_100",
+	"res_101",
+	"res_102",
+	"res_103",
+	"res_104",
+	"res_105",
+	"res_106",
+	"res_107",
+	"res_108",
+	"res_109",
+	"res_110",
+	"res_111",
+	"res_112",
+	"res_113",
+	"res_114",
+	"res_115",
+	"res_116",
+	"res_117",
+	"res_118",
+	"res_119",
+	"res_120",
+	"res_121",
+	"res_122",
+	"res_123",
+	"res_124",
+	"res_125",
+	"res_126",
+	"res_127",
+	"res_128",
+	"res_129",
+	"res_130",
+	"res_131",
+	"res_132",
+	"res_133",
+	"res_134",
+	"res_135",
+	"res_136",
+	"res_137",
+	"res_138",
+	"res_139",
+	"res_140",
+	"res_141",
+	"res_142",
+	"res_143",
+	"res_144",
+	"res_145",
+	"res_146",
+	"res_147",
+	"res_148",
+	"res_149",
+	"res_150",
+	"res_151",
+	"res_152",
+	"res_153",
+	"res_154",
+	"res_155",
+	"res_156",
+	"res_157",
+	"res_158",
+	"res_159",
+	"res_160",
+	"res_161",
+	"res_162",
+	"res_163",
+	"res_164",
+	"res_165",
+	"res_166",
+	"res_167",
+	"res_168",
+	"res_169",
+	"res_170",
+	"res_171",
+	"res_172",
+	"res_173",
+	"res_174",
+	"res_175",
+	"res_176",
+	"res_177",
+	"res_178",
+	"res_179",
+	"res_180",
+	"res_181",
+	"res_182",
+	"res_183",
+	"res_184",
+	"res_185",
+	"res_186",
+	"res_187",
+	"res_188",
+	"res_189",
+	"res_190",
+	"res_191",
+	"res_192",
+	"res_193",
+	"res_194",
+	"res_195",
+	"res_196",
+	"res_197",
+	"res_198",
+	"res_199",
+	"res_200",
+	"res_201",
+	"res_202",
+	"res_203",
+	"res_204",
+	"res_205",
+	"res_206",
+	"res_207",
+	"res_208",
+	"res_209",
+	"res_210",
+	"res_211",
+	"res_212",
+	"res_213",
+	"res_214",
+	"res_215",
+	"res_216",
+	"res_217",
+	"res_218",
+	"res_219",
+	"res_220",
+	"res_221",
+	"res_222",
+	"res_223",
+	"res_224",
+	"res_225",
+	"res_226",
+	"res_227",
+	"res_228",
+	"res_229",
+	"res_230",
+	"res_231",
+	"res_232",
+	"res_233",
+	"res_234",
+	"res_235",
+	"res_236",
+	"res_237",
+	"res_238",
+	"res_239",
+	"res_240",
+	"res_241",
+	"res_242",
+	"res_243",
+	"res_244",
+	"res_245",
+	"res_246",
+	"res_247",
+	"res_248",
+	"res_249",
+	"res_250",
+	"res_251",
+	"res_252",
+	"res_253",
+	"res_254",
+	"oem_unit",
+};
+
 static struct inode *stlmfs_get_inode(struct super_block *sb)
 {
 	struct inode *inode = new_inode(sb);

@@ -815,6 +1337,18 @@ DEFINE_TLM_CLASS(persistent_tlmo, "persistent", 0,
 DEFINE_TLM_CLASS(value_tlmo, "value", 0,
 		 S_IFREG | S_IRUSR, &de_read_fops, NULL);
 
+static inline struct dentry *
+stlmfs_lookup_by_name(struct dentry *parent, const char *dname)
+{
+	struct qstr qstr;
+
+	qstr.name = dname;
+	qstr.len = strlen(dname);
+	qstr.hash = full_name_hash(parent, qstr.name, qstr.len);
+
+	return d_lookup(parent, &qstr);
+}
+
 static int scmi_telemetry_de_populate(struct super_block *sb,
 				      struct scmi_tlm_setup *tsp,
 				      struct dentry *parent,

@@ -1659,6 +2193,150 @@ static struct dentry *stlmfs_create_root_dentry(struct super_block *sb)
 	return dentry;
 }
 
+static int scmi_telemetry_de_subdir_symlink(struct super_block *sb,
+					    struct scmi_tlm_setup *tsp,
+					    const struct scmi_telemetry_de *de,
+					    struct dentry *parent)
+{
+	struct dentry *dentry;
+	struct inode *inode;
+	int ret;

I notice that ret isn't assigned a value and the function returns ret without
initialising.

Yep, my bad: I think it is just a leftover from some last minute cleanup
I have done...it seems to cause only harmless (but noisy) error
messages...thanks for testing...I will fix !

quoted

+
+	if (IS_ERR(parent))
 

[snip]

I will continue reviewing,

Yes please, thanks for having a look.

Thanks,
Cristian