From: Arnd Bergmann <arnd@xxxxxxxx> commit 994a04a20b03128838ec0250a0e266aab24d23f1 upstream. 32-bit processors cannot generally access 64-bit MMIO registers atomically, and it is unknown in which order the two halves of this registers would need to be read: drivers/thermal/intel/int340x_thermal/processor_thermal_mbox.c: In function 'send_mbox_cmd': drivers/thermal/intel/int340x_thermal/processor_thermal_mbox.c:79:37: error: implicit declaration of function 'readq'; did you mean 'readl'? [-Werror=implicit-function-declaration] 79 | *cmd_resp = readq((void __iomem *) (proc_priv->mmio_base + MBOX_OFFSET_DATA)); | ^~~~~ | readl The driver already does not build for anything other than x86, so limit it further to x86-64. Fixes: aeb58c860dc5 ("thermal/drivers/int340x: processor_thermal: Suppot 64 bit RFIM responses") Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx> Reviewed-by: Srinivas Pandruvada <srinivas.pandruvada@xxxxxxxxxxxxxxx> Reviewed-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> Signed-off-by: Sumeet Pawnikar <sumeet.r.pawnikar@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/thermal/intel/int340x_thermal/Kconfig | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/drivers/thermal/intel/int340x_thermal/Kconfig +++ b/drivers/thermal/intel/int340x_thermal/Kconfig @@ -5,12 +5,12 @@ config INT340X_THERMAL tristate "ACPI INT340X thermal drivers" - depends on X86 && ACPI && PCI + depends on X86_64 && ACPI && PCI select THERMAL_GOV_USER_SPACE select ACPI_THERMAL_REL select ACPI_FAN select INTEL_SOC_DTS_IOSF_CORE - select PROC_THERMAL_MMIO_RAPL if X86_64 && POWERCAP + select PROC_THERMAL_MMIO_RAPL if POWERCAP help Newer laptops and tablets that use ACPI may have thermal sensors and other devices with thermal control capabilities outside the core Patches currently in stable-queue which might be from arnd@xxxxxxxx are queue-5.15/thermal-int340x-limit-kconfig-to-64-bit.patch