[PATCH 5/5] powerpc/microwatt: Add SMP support

[Paul Mackerras]

This adds support for Microwatt systems with more than one core, and
updates the device tree for a 2-core version.  (This does not prevent
the kernel from running on a single-core system.)

Signed-off-by: Paul Mackerras <paulus at ozlabs.org>
---
 arch/powerpc/boot/dts/microwatt.dts          | 34 ++++++++++++++++++--
 arch/powerpc/platforms/microwatt/Kconfig     |  2 +-
 arch/powerpc/platforms/microwatt/Makefile    |  1 +
 arch/powerpc/platforms/microwatt/microwatt.h |  1 +
 arch/powerpc/platforms/microwatt/setup.c     | 10 ++++++
 5 files changed, 45 insertions(+), 3 deletions(-)

diff --git a/arch/powerpc/boot/dts/microwatt.dts b/arch/powerpc/boot/dts/microwatt.dts
index 6e575e841a7b..89281dc975b3 100644
--- a/arch/powerpc/boot/dts/microwatt.dts
+++ b/arch/powerpc/boot/dts/microwatt.dts
@@ -142,6 +142,36 @@ PowerPC,Microwatt at 0 {
 			ibm,mmu-lpid-bits = <12>;
 			ibm,mmu-pid-bits = <20>;
 		};
+
+		PowerPC,Microwatt at 1 {
+			i-cache-sets = <2>;
+			ibm,dec-bits = <64>;
+			reservation-granule-size = <64>;
+			clock-frequency = <100000000>;
+			timebase-frequency = <100000000>;
+			i-tlb-sets = <1>;
+			ibm,ppc-interrupt-server#s = <1>;
+			i-cache-block-size = <64>;
+			d-cache-block-size = <64>;
+			d-cache-sets = <2>;
+			i-tlb-size = <64>;
+			cpu-version = <0x990000>;
+			status = "okay";
+			i-cache-size = <0x1000>;
+			ibm,processor-radix-AP-encodings = <0x0c 0xa0000010 0x20000015 0x4000001e>;
+			tlb-size = <0>;
+			tlb-sets = <0>;
+			device_type = "cpu";
+			d-tlb-size = <128>;
+			d-tlb-sets = <2>;
+			reg = <1>;
+			general-purpose;
+			64-bit;
+			d-cache-size = <0x1000>;
+			ibm,chip-id = <0>;
+			ibm,mmu-lpid-bits = <12>;
+			ibm,mmu-pid-bits = <20>;
+		};
 	};
 
 	soc at c0000000 {
@@ -154,8 +184,8 @@ soc at c0000000 {
 
 		interrupt-controller at 4000 {
 			compatible = "openpower,xics-presentation", "ibm,ppc-xicp";
-			ibm,interrupt-server-ranges = <0x0 0x1>;
-			reg = <0x4000 0x100>;
+			ibm,interrupt-server-ranges = <0x0 0x2>;
+			reg = <0x4000 0x10 0x4010 0x10>;
 		};
 
 		ICS: interrupt-controller at 5000 {
diff --git a/arch/powerpc/platforms/microwatt/Kconfig b/arch/powerpc/platforms/microwatt/Kconfig
index 1d5cc1ae3636..8911ea7cf12e 100644
--- a/arch/powerpc/platforms/microwatt/Kconfig
+++ b/arch/powerpc/platforms/microwatt/Kconfig
@@ -1,6 +1,6 @@
 # SPDX-License-Identifier: GPL-2.0
 config PPC_MICROWATT
-	depends on PPC_BOOK3S_64 && !SMP
+	depends on PPC_BOOK3S_64
 	bool "Microwatt SoC platform"
 	select PPC_XICS
 	select PPC_ICS_NATIVE
diff --git a/arch/powerpc/platforms/microwatt/Makefile b/arch/powerpc/platforms/microwatt/Makefile
index 116d6d3ad3f0..d973b2ab4042 100644
--- a/arch/powerpc/platforms/microwatt/Makefile
+++ b/arch/powerpc/platforms/microwatt/Makefile
@@ -1 +1,2 @@
 obj-y	+= setup.o rng.o
+obj-$(CONFIG_SMP) += smp.o
diff --git a/arch/powerpc/platforms/microwatt/microwatt.h b/arch/powerpc/platforms/microwatt/microwatt.h
index 335417e95e66..891aa2800768 100644
--- a/arch/powerpc/platforms/microwatt/microwatt.h
+++ b/arch/powerpc/platforms/microwatt/microwatt.h
@@ -3,5 +3,6 @@
 #define _MICROWATT_H
 
 void microwatt_rng_init(void);
+void microwatt_init_smp(void);
 
 #endif /* _MICROWATT_H */
diff --git a/arch/powerpc/platforms/microwatt/setup.c b/arch/powerpc/platforms/microwatt/setup.c
index 97828a99780d..d966bf1f57f7 100644
--- a/arch/powerpc/platforms/microwatt/setup.c
+++ b/arch/powerpc/platforms/microwatt/setup.c
@@ -29,6 +29,15 @@ static int __init microwatt_populate(void)
 }
 machine_arch_initcall(microwatt, microwatt_populate);
 
+static int __init microwatt_probe(void)
+{
+	/* Main reason for having this is to start the other CPU(s) */
+#ifdef CONFIG_SMP
+	microwatt_init_smp();
+#endif
+	return 1;
+}
+
 static void __init microwatt_setup_arch(void)
 {
 	microwatt_rng_init();
@@ -45,6 +54,7 @@ static void microwatt_idle(void)
 define_machine(microwatt) {
 	.name			= "microwatt",
 	.compatible		= "microwatt-soc",
+	.probe			= microwatt_probe,
 	.init_IRQ		= microwatt_init_IRQ,
 	.setup_arch		= microwatt_setup_arch,
 	.progress		= udbg_progress,
-- 
2.47.1