arm-bsp/boot-wrapper-aarch64: Enable SMP support for fvp-baser-aemv8r64

Downstream patch "Allow --enable-psci to choose between smc and hvc"
from boot-wrapper-aarch64. With this patch, kernel can bring up
secondary core successfully through hvc call.

Issue-Id: SCM-2949
Signed-off-by: Huifeng Zhang <Huifeng.Zhang@arm.com>
Change-Id: Iecc99d925317ab7981284671cb8cc4ef1894e6d6
Signed-off-by: Jon Mason <jon.mason@arm.com>

meta-arm-bsp/documentation/fvp-baser-aemv8r64.md

@@ -153,10 +153,3 @@ Devices supported in the kernel
 - virtio network
 - watchdog
 - rtc
-
-
-Devices not supported or not functional
----------------------------------------
-
-- Only one CPU since SMP is not functional in boot-wrapper-aarch64 yet
-

meta-arm-bsp/recipes-bsp/boot-wrapper-aarch64/boot-wrapper-aarch64-fvp-baser-aemv8r64.inc

@@ -4,11 +4,12 @@ FILESEXTRAPATHS_prepend := "${THISDIR}/files/${MACHINE}:"
 SRC_URI_append = " \
     file://0001-Decouple-V2M_SYS-config-by-auto-detect-dtb-node.patch \
     file://0002-arch64-Introduce-EL2-boot-code-for-v8-r64.patch \
+    file://0003-Allow-enable-psci-to-choose-between-smc-and-hvc.patch \
     "
 
 BOOT_WRAPPER_AARCH64_CMDLINE = "\
 earlycon console=ttyAMA0 loglevel=8 rootfstype=ext4 root=/dev/vda1 rw"
 
-EXTRA_OECONF_remove = "--enable-psci"
+EXTRA_OECONF += "--enable-psci=hvc"
 
 TUNE_CCARGS = ""

meta-arm-bsp/recipes-bsp/boot-wrapper-aarch64/files/fvp-baser-aemv8r64/0003-Allow-enable-psci-to-choose-between-smc-and-hvc.patch

@@ -0,0 +1,83 @@
+From 5120127e5f767b44a087c741a3438cef1e22ed50 Mon Sep 17 00:00:00 2001
+From: Qi Feng <qi.feng@arm.com>
+Date: Wed, 26 May 2021 17:52:01 +0800
+Subject: [PATCH] Allow --enable-psci to choose between smc and hvc
+
+According to Armv8-R AArch64 manual [1], Armv8-R AArch64 does not
+support smc:
+
+- Pseudocode for AArch64.CheckForSMCUndefOrTrap has this snippet:
+
+      if !HaveEL(EL3) || PSTATE.EL == EL0 then
+          UNDEFINED;
+
+  And Armv8-R AArch64 does not have EL3.
+
+- In the document of HCR_EL2 TSC bit:
+  If EL3 is not implemented and HCR_EL2.NV is 0, it is IMPLEMENTATION
+  DEFINED whether this bit is:
+  - RES0.
+  - Implemented with the functionality as described in HCR_EL2.TSC.
+
+So hvc is needed in this situation. And due to the lack of libfdt, the
+psci method cannot be modified at runtime.
+
+To use smc, use --enable-psci or --enable-psci=smc.
+To use hvc, use --enable-psci=hvc.
+
+[1]: https://developer.arm.com/documentation/ddi0600/latest/
+
+Issue-Id: SCM-2654
+Signed-off-by: Qi Feng <qi.feng@arm.com>
+Change-Id: Ib8afabdad2d98bc37371d165bbb6f1f9b88bfc87
+
+Upstream-Status: Pending
+Signed-off-by: Huifeng Zhang <Huifeng.Zhang@arm.com>
+---
+ Makefile.am  |  2 +-
+ configure.ac | 14 +++++++++-----
+ 2 files changed, 10 insertions(+), 6 deletions(-)
+
+diff --git a/Makefile.am b/Makefile.am
+index ef6b793..a9ddd16 100644
+--- a/Makefile.am
++++ b/Makefile.am
+@@ -47,7 +47,7 @@ BOOTMETHOD	:= psci.o
+ OFILES		+= psci.o
+ PSCI_NODE	:= psci {				\
+ 			compatible = \"arm,psci\";	\
+-			method = \"smc\";		\
++			method = \"$(PSCI_METHOD)\";	\
+ 			cpu_on = <$(PSCI_CPU_ON)>;	\
+ 			cpu_off = <$(PSCI_CPU_OFF)>;	\
+ 		   };
+diff --git a/configure.ac b/configure.ac
+index 6914eb4..9aab4a1 100644
+--- a/configure.ac
++++ b/configure.ac
+@@ -83,13 +83,17 @@ AS_IF([test "x$X_IMAGE" != "x"],
+ # Allow a user to pass --enable-psci
+ AC_ARG_ENABLE([psci],
+ 	AS_HELP_STRING([--enable-psci], [enable the psci boot method]),
+-	[USE_PSCI=$enableval])
+-AM_CONDITIONAL([PSCI], [test "x$USE_PSCI" = "xyes"])
+-AS_IF([test "x$USE_PSCI" = "xyes"], [], [USE_PSCI=no])
+-
+-AS_IF([test "x$USE_PSCI" != "xyes" -a "x$KERNEL_ES" = "x32"],
++	[case "${enableval}" in
++		yes|smc) USE_PSCI=smc ;;
++		hvc) USE_PSCI=hvc ;;
++		*) AC_MSG_ERROR([Bad value "${enableval}" for --enable-psci. Use "smc" or "hvc"]) ;;
++	esac])
++AM_CONDITIONAL([PSCI], [test "x$USE_PSCI" = "xyes" -o "x$USE_PSCI" = "xsmc" -o "x$USE_PSCI" = "xhvc"])
++
++AS_IF([test "x$USE_PSCI" = "xno" -a "x$KERNEL_ES" = "x32"],
+ 	[AC_MSG_ERROR([With an AArch32 kernel, boot method must be PSCI.])]
+ )
++AC_SUBST([PSCI_METHOD], [$USE_PSCI])
+ 
+ # Allow a user to pass --with-initrd
+ AC_ARG_WITH([initrd],
+-- 
+2.32.0
+