hwmon: (peci/cputemp) Add Intel Sapphire Rapids support

Add support to read DTS for reading Intel Sapphire Rapids platform.

Signed-off-by: Patrick Rudolph <patrick.rudolph@9elements.com>
Signed-off-by: Naresh Solanki <Naresh.Solanki@9elements.com>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Iwona Winiarska <iwona.winiarska@intel.com>
Signed-off-by: Iwona Winiarska <iwona.winiarska@intel.com>
Link: https://lore.kernel.org/r/20230725104354.33920-2-Naresh.Solanki@9elements.com

hwmon: peci: constify pointers to hwmon_channel_info

Statically allocated array of pointed to hwmon_channel_info can be made
const for safety.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

hwmon: (peci/cputemp) Fix miscalculated DTS for SKX

For Skylake, DTS temperature of the CPU is reported in S10.6 format
instead of S8.8.

Reported-by: Paul Fertser <fercerpav@gmail.com>
Link: https://lore.kernel.org/lkml/ZBhHS7v+98NK56is@home.paul.comp/
Signed-off-by: Iwona Winiarska <iwona.winiarska@intel.com>
Link: https://lore.kernel.org/r/20230321090410.866766-1-iwona.winiarska@intel.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

hwmon: (peci/cputemp) Fix off-by-one in coretemp_label allocation

The find_last_bit() call produces the index of the highest-numbered
core in core_mask; because cores are numbered from zero, the number of
elements we need to allocate is one more than that.

Signed-off-by: Zev Weiss <zev@bewilderbeest.net>
Cc: stable@kernel.org # v5.18
Fixes: bf3608f338e9 ("hwmon: peci: Add cputemp driver")
Reviewed-by: Iwona Winiarska <iwona.winiarska@intel.com>
Link: https://lore.kernel.org/r/20230202021825.21486-1-zev@bewilderbeest.net
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

hwmon: (peci/cputemp) Use HWMON_CHANNEL_INFO macro

The HWMON_CHANNEL_INFO macro simplifies the code, reduces the likelihood
of errors, and makes the code easier to read.

The conversion was done automatically with coccinelle. The semantic patch
used to make this change is as follows.

@s@
identifier i,j,ty;
@@

-struct hwmon_channel_info j = {
- .type = ty,
- .config = i,
-};

@r@
initializer list elements;
identifier s.i;
@@

-u32 i[] = {
- elements,
- 0
-};

@script:ocaml t@
ty << s.ty;
elements << r.elements;
shorter;
elems;
@@

shorter :=
make_ident (List.hd(List.rev (Str.split (Str.regexp "_") ty)));
elems :=
make_ident
(String.concat ","
(List.map (fun x -> Printf.sprintf "\n\t\t\t %s" x)
(Str.split (Str.regexp " , ") elements)))

@@
identifier s.j,t.shorter;
identifier t.elems;
@@

- &j
+ HWMON_CHANNEL_INFO(shorter,elems)

This patch does not introduce functional changes. Many thanks to
Julia Lawall for providing the coccinelle script.

Cc: Iwona Winiarska <iwona.winiarska@intel.com>
Reviewed-by: Iwona Winiarska <iwona.winiarska@intel.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

hwmon: peci: Add cputemp driver

Add peci-cputemp driver for Digital Thermal Sensor (DTS) thermal
readings of the processor package and processor cores that are
accessible via the PECI interface.

The main use case for the driver (and PECI interface) is out-of-band
management, where we're able to obtain the DTS readings from an external
entity connected with PECI, e.g. BMC on server platforms.

Co-developed-by: Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com>
Signed-off-by: Iwona Winiarska <iwona.winiarska@intel.com>
Link: https://lore.kernel.org/r/20220208153639.255278-11-iwona.winiarska@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>