powerpc/pseries: define driver for Platform KeyStore

PowerVM provides an isolated Platform Keystore(PKS) storage allocation
for each LPAR with individually managed access controls to store
sensitive information securely. It provides a new set of hypervisor
calls for Linux kernel to access PKS storage.

Define POWER LPAR Platform KeyStore(PLPKS) driver using H_CALL interface
to access PKS storage.

Signed-off-by: Nayna Jain <nayna@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220723113048.521744-2-nayna@linux.ibm.com

Author: naynajain

arch/powerpc/include/asm/hvcall.h

@@ -79,6 +79,7 @@
 #define H_NOT_ENOUGH_RESOURCES -44
 #define H_R_STATE       -45
 #define H_RESCINDED     -46
+#define H_P1		-54
 #define H_P2		-55
 #define H_P3		-56
 #define H_P4		-57
@@ -98,6 +99,8 @@
 #define H_OP_MODE	-73
 #define H_COP_HW	-74
 #define H_STATE		-75
+#define H_IN_USE	-77
+#define H_ABORTED	-78
 #define H_UNSUPPORTED_FLAG_START	-256
 #define H_UNSUPPORTED_FLAG_END		-511
 #define H_MULTI_THREADS_ACTIVE	-9005
@@ -322,6 +325,14 @@
 #define H_SCM_UNBIND_ALL        0x3FC
 #define H_SCM_HEALTH            0x400
 #define H_SCM_PERFORMANCE_STATS 0x418
+#define H_PKS_GET_CONFIG	0x41C
+#define H_PKS_SET_PASSWORD	0x420
+#define H_PKS_GEN_PASSWORD	0x424
+#define H_PKS_WRITE_OBJECT	0x42C
+#define H_PKS_GEN_KEY		0x430
+#define H_PKS_READ_OBJECT	0x434
+#define H_PKS_REMOVE_OBJECT	0x438
+#define H_PKS_CONFIRM_OBJECT_FLUSHED	0x43C
 #define H_RPT_INVALIDATE	0x448
 #define H_SCM_FLUSH		0x44C
 #define H_GET_ENERGY_SCALE_INFO	0x450

arch/powerpc/platforms/pseries/Kconfig

@@ -142,6 +142,19 @@ config IBMEBUS
 	help
 	  Bus device driver for GX bus based adapters.
 
+config PSERIES_PLPKS
+	depends on PPC_PSERIES
+	bool "Support for the Platform Key Storage"
+	help
+	  PowerVM provides an isolated Platform Keystore(PKS) storage
+	  allocation for each LPAR with individually managed access
+	  controls to store sensitive information securely. It can be
+	  used to store asymmetric public keys or secrets as required
+	  by different usecases. Select this config to enable
+	  operating system interface to hypervisor to access this space.
+
+	  If unsure, select N.
+
 config PAPR_SCM
 	depends on PPC_PSERIES && MEMORY_HOTPLUG && LIBNVDIMM
 	tristate "Support for the PAPR Storage Class Memory interface"

arch/powerpc/platforms/pseries/Makefile

@@ -28,6 +28,7 @@ obj-$(CONFIG_PAPR_SCM)		+= papr_scm.o
 obj-$(CONFIG_PPC_SPLPAR)	+= vphn.o
 obj-$(CONFIG_PPC_SVM)		+= svm.o
 obj-$(CONFIG_FA_DUMP)		+= rtas-fadump.o
+obj-$(CONFIG_PSERIES_PLPKS) += plpks.o
 
 obj-$(CONFIG_SUSPEND)		+= suspend.o
 obj-$(CONFIG_PPC_VAS)		+= vas.o vas-sysfs.o