powerpc/pseries: Add H_GET_CPU_CHARACTERISTICS flags & wrapper

A new hypervisor call has been defined to communicate various
characteristics of the CPU to guests. Add definitions for the hcall
number, flags and a wrapper function.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

2 files changed, 31 insertions, 0 deletions

diff --git a/arch/powerpc/include/asm/hvcall.h b/arch/powerpc/include/asm/hvcall.h
index a409177be8bd..f0461618bf7b 100644
--- a/arch/powerpc/include/asm/hvcall.h
+++ b/arch/powerpc/include/asm/hvcall.h
@@ -241,6 +241,7 @@
 #define H_GET_HCA_INFO          0x1B8
 #define H_GET_PERF_COUNT        0x1BC
 #define H_MANAGE_TRACE          0x1C0
+#define H_GET_CPU_CHARACTERISTICS 0x1C8
 #define H_FREE_LOGICAL_LAN_BUFFER 0x1D4
 #define H_QUERY_INT_STATE       0x1E4
 #define H_POLL_PENDING          0x1D8
@@ -330,6 +331,17 @@
 #define H_SIGNAL_SYS_RESET_ALL_OTHERS           -2
 /* >= 0 values are CPU number */
 
+/* H_GET_CPU_CHARACTERISTICS return values */
+#define H_CPU_CHAR_SPEC_BAR_ORI31       (1ull << 63) // IBM bit 0
+#define H_CPU_CHAR_BCCTRL_SERIALISED    (1ull << 62) // IBM bit 1
+#define H_CPU_CHAR_L1D_FLUSH_ORI30      (1ull << 61) // IBM bit 2
+#define H_CPU_CHAR_L1D_FLUSH_TRIG2      (1ull << 60) // IBM bit 3
+#define H_CPU_CHAR_L1D_THREAD_PRIV      (1ull << 59) // IBM bit 4
+
+#define H_CPU_BEHAV_FAVOUR_SECURITY     (1ull << 63) // IBM bit 0
+#define H_CPU_BEHAV_L1D_FLUSH_PR        (1ull << 62) // IBM bit 1
+#define H_CPU_BEHAV_BNDS_CHK_SPEC_BAR   (1ull << 61) // IBM bit 2
+
 /* Flag values used in H_REGISTER_PROC_TBL hcall */
 #define PROC_TABLE_OP_MASK      0x18
 #define PROC_TABLE_DEREG        0x10
@@ -436,6 +448,11 @@ static inline unsigned int get_longbusy_msecs(int longbusy_rc)
         }
 }
 
+struct h_cpu_char_result {
+        u64 character;
+        u64 behaviour;
+};
+
 #endif /* __ASSEMBLY__ */
 #endif /* __KERNEL__ */
 #endif /* _ASM_POWERPC_HVCALL_H */
diff --git a/arch/powerpc/include/asm/plpar_wrappers.h b/arch/powerpc/include/asm/plpar_wrappers.h
index 7f01b22fa6cb..55eddf50d149 100644
--- a/arch/powerpc/include/asm/plpar_wrappers.h
+++ b/arch/powerpc/include/asm/plpar_wrappers.h
@@ -326,4 +326,18 @@ static inline long plapr_signal_sys_reset(long cpu)
         return plpar_hcall_norets(H_SIGNAL_SYS_RESET, cpu);
 }
 
+static inline long plpar_get_cpu_characteristics(struct h_cpu_char_result *p)
+{
+        unsigned long retbuf[PLPAR_HCALL_BUFSIZE];
+        long rc;
+
+        rc = plpar_hcall(H_GET_CPU_CHARACTERISTICS, retbuf);
+        if (rc == H_SUCCESS) {
+                p->character = retbuf[0];
+                p->behaviour = retbuf[1];
+        }
+
+        return rc;
+}
+
 #endif /* _ASM_POWERPC_PLPAR_WRAPPERS_H */