[PATCH 2/2] hwmon: (coretemp) Add TjMax for Silvermont through Tremont Atoms

[Laveesh Bansal <laveeshb@laveeshbansal.com>]

Add fallback TjMax values for Intel Atom processors based on Silvermont,
Airmont, Goldmont, and Tremont microarchitectures. These processors
support MSR_IA32_TEMPERATURE_TARGET for reading TjMax directly, so these
table entries serve as fallback values only when the MSR read fails
(e.g., in some virtualization scenarios).

Added processors and TjMax values:

- INTEL_ATOM_SILVERMONT (0x37, Bay Trail):
  - Stepping 9 (E38xx embedded): 110C
  - Other steppings (Z37xx tablet): 90C
  Stepping identified from Intel E3800 Specification Update.

- INTEL_ATOM_SILVERMONT_MID (0x4a, Merrifield): 90C

- INTEL_ATOM_SILVERMONT_MID2 (0x5a, Moorefield): 90C

- INTEL_ATOM_AIRMONT (0x4c, Cherry Trail): 90C

- INTEL_ATOM_GOLDMONT (0x5c, Apollo Lake): 105C

- INTEL_ATOM_GOLDMONT_PLUS (0x7a, Gemini Lake): 105C

- INTEL_ATOM_TREMONT (0x96, Elkhart Lake): 105C

- INTEL_ATOM_TREMONT_L (0x9c, Jasper Lake): 105C

Not included (MSR reads work reliably, server/specialized chips):
- INTEL_ATOM_SILVERMONT_D (Avoton): Server, Tcase 97C
- INTEL_ATOM_GOLDMONT_D (Denverton): Server, Tcase 82C
- INTEL_ATOM_AIRMONT_NP (Lightning Mountain): Network processor
- INTEL_ATOM_TREMONT_D (Jacobsville): Server
- INTEL_ATOM_GRACEMONT (Alder Lake-N): Very new, MSR works

Reference: Intel datasheets and ARK processor specifications
- Z3600/Z3700 datasheet: https://www.intel.com/content/dam/www/public/us/en/documents/datasheets/atom-z36xxx-z37xxx-datasheet-vol-1.pdf
- E3845 ARK: https://www.intel.com/content/www/us/en/products/sku/78475/intel-atom-processor-e3845-2m-cache-1-91-ghz/specifications.html
- E3800 Spec Update: https://community.intel.com/cipcp26785/attachments/cipcp26785/embedded-atom-processors/4708/1/600834-329901-intel-atom-processor-e3800-product-family-su-rev015.pdf

Signed-off-by: Laveesh Bansal <laveeshb@laveeshbansal.com>
---
 drivers/hwmon/coretemp.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/drivers/hwmon/coretemp.c b/drivers/hwmon/coretemp.c
index ad79db5a183e..d2dfa4e30407 100644
--- a/drivers/hwmon/coretemp.c
+++ b/drivers/hwmon/coretemp.c
@@ -145,6 +145,15 @@ static const struct tjmax_model tjmax_model_table[] = {
 							 * Also matches S12x0 (stepping 9), covered by
 							 * PCI table
 							 */
+	{ INTEL_ATOM_SILVERMONT,      9, 110000 },	/* Atom Bay Trail E38xx (embedded) */
+	{ INTEL_ATOM_SILVERMONT,      ANY, 90000 },	/* Atom Bay Trail Z37xx (tablet) */
+	{ INTEL_ATOM_SILVERMONT_MID,  ANY, 90000 },	/* Atom Merrifield (Z34xx) */
+	{ INTEL_ATOM_SILVERMONT_MID2, ANY, 90000 },	/* Atom Moorefield (Z35xx) */
+	{ INTEL_ATOM_AIRMONT,	      ANY, 90000 },	/* Atom Cherry Trail (Z8xxx) */
+	{ INTEL_ATOM_GOLDMONT,	      ANY, 105000 },	/* Atom Apollo Lake (J3xxx, N3xxx, E39xx) */
+	{ INTEL_ATOM_GOLDMONT_PLUS,   ANY, 105000 },	/* Atom Gemini Lake (J4xxx, N4xxx, N5xxx) */
+	{ INTEL_ATOM_TREMONT,	      ANY, 105000 },	/* Atom Elkhart Lake */
+	{ INTEL_ATOM_TREMONT_L,	      ANY, 105000 },	/* Atom Jasper Lake */
 };
 
 static bool is_pkg_temp_data(struct temp_data *tdata)
-- 
2.43.0