[PATCH v2 3/9] powerpc/powernv: Add icp_native_cause_ipi_rm

[Suresh Warrier <warrier@linux.vnet.ibm.com>]

Function to cause an IPI. Requires kvm_hstate.xics_phys
to be initialized with physical address of XICS.

Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
---
 arch/powerpc/include/asm/xics.h       |  1 +
 arch/powerpc/sysdev/xics/icp-native.c | 19 +++++++++++++++++++
 2 files changed, 20 insertions(+)

diff --git a/arch/powerpc/include/asm/xics.h b/arch/powerpc/include/asm/xics.h
index 0e25bdb..2546048 100644
--- a/arch/powerpc/include/asm/xics.h
+++ b/arch/powerpc/include/asm/xics.h
@@ -30,6 +30,7 @@
 #ifdef CONFIG_PPC_ICP_NATIVE
 extern int icp_native_init(void);
 extern void icp_native_flush_interrupt(void);
+extern void icp_native_cause_ipi_rm(int cpu);
 #else
 static inline int icp_native_init(void) { return -ENODEV; }
 #endif
diff --git a/arch/powerpc/sysdev/xics/icp-native.c b/arch/powerpc/sysdev/xics/icp-native.c
index eae3265..e39b18a 100644
--- a/arch/powerpc/sysdev/xics/icp-native.c
+++ b/arch/powerpc/sysdev/xics/icp-native.c
@@ -159,6 +159,25 @@ static void icp_native_cause_ipi(int cpu, unsigned long data)
 	icp_native_set_qirr(cpu, IPI_PRIORITY);
 }
 
+void icp_native_cause_ipi_rm(int cpu)
+{
+	/*
+	 * Currently not used to send IPIs to another CPU
+	 * on the same core. Only caller is KVM real mode.
+	 * Need the physical address of the XICS to be
+	 * previously saved in kvm_hstate in the paca.
+	 */
+	unsigned long xics_phys;
+
+	/*
+	 * Just like the cause_ipi functions, it is required to
+	 * include a full barrier (out8 includes a sync) before
+	 * causing the IPI.
+	 */
+	xics_phys = paca[cpu].kvm_hstate.xics_phys;
+	out_rm8((u8 *)(xics_phys + XICS_MFRR), IPI_PRIORITY);
+}
+
 /*
  * Called when an interrupt is received on an off-line CPU to
  * clear the interrupt, so that the CPU can go back to nap mode.
-- 
1.8.3.4