Merge tag 'riscv-for-linus-5.20-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux

Pull RISC-V updates from Palmer Dabbelt:

 - Enabling the FPU is now a static_key

 - Improvements to the Svpbmt support

 - CPU topology bindings for a handful of systems

 - Support for systems with 64-bit hart IDs

 - Many settings have been enabled in the defconfig, including both
   support for the StarFive systems and many of the Docker requirements

There are also a handful of cleanups and improvements, as usual.

* tag 'riscv-for-linus-5.20-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (28 commits)
  riscv: enable Docker requirements in defconfig
  riscv: convert the t-head pbmt errata to use the __nops macro
  riscv: introduce nops and __nops macros for NOP sequences
  RISC-V: Add fast call path of crash_kexec()
  riscv: mmap with PROT_WRITE but no PROT_READ is invalid
  riscv/efi_stub: Add 64bit boot-hartid support on RV64
  riscv: cpu: Add 64bit hartid support on RV64
  riscv: smp: Add 64bit hartid support on RV64
  riscv: spinwait: Fix hartid variable type
  riscv: cpu_ops_sbi: Add 64bit hartid support on RV64
  riscv: dts: sifive: "fix" pmic watchdog node name
  riscv: dts: canaan: Add k210 topology information
  riscv: dts: sifive: Add fu740 topology information
  riscv: dts: sifive: Add fu540 topology information
  riscv: dts: starfive: Add JH7100 CPU topology
  RISC-V: Add CONFIG_{NON,}PORTABLE
  riscv: config: enable SOC_STARFIVE in defconfig
  riscv: dts: microchip: Add mpfs' topology information
  riscv: Kconfig.socs: Add comments
  riscv: Kconfig.erratas: Add comments
  ...

1 files changed, 35 insertions, 12 deletions

diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index 51713e03c934..5c52a82e83a8 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -223,6 +223,21 @@ source "arch/riscv/Kconfig.erratas"
 
 menu "Platform type"
 
+config NONPORTABLE
+	bool "Allow configurations that result in non-portable kernels"
+	help
+	  RISC-V kernel binaries are compatible between all known systems
+	  whenever possible, but there are some use cases that can only be
+	  satisfied by configurations that result in kernel binaries that are
+	  not portable between systems.
+
+	  Selecting N does not guarantee kernels will be portable to all known
+	  systems.  Selecting any of the options guarded by NONPORTABLE will
+	  result in kernel binaries that are unlikely to be portable between
+	  systems.
+
+	  If unsure, say N.
+
 choice
 	prompt "Base ISA"
 	default ARCH_RV64I
@@ -232,6 +247,7 @@ choice
 
 config ARCH_RV32I
 	bool "RV32I"
+	depends on NONPORTABLE
 	select 32BIT
 	select GENERIC_LIB_ASHLDI3
 	select GENERIC_LIB_ASHRDI3
@@ -352,11 +368,11 @@ config RISCV_ISA_C
 	bool "Emit compressed instructions when building Linux"
 	default y
 	help
-	   Adds "C" to the ISA subsets that the toolchain is allowed to emit
-	   when building Linux, which results in compressed instructions in the
-	   Linux binary.
+	  Adds "C" to the ISA subsets that the toolchain is allowed to emit
+	  when building Linux, which results in compressed instructions in the
+	  Linux binary.
 
-	   If you don't know what to do here, say Y.
+	  If you don't know what to do here, say Y.
 
 config RISCV_ISA_SVPBMT
 	bool "SVPBMT extension support"
@@ -385,7 +401,7 @@ config FPU
 
 	  If you don't know what to do here, say Y.
 
-endmenu
+endmenu # "Platform type"
 
 menu "Kernel features"
 
@@ -474,7 +490,7 @@ config COMPAT
 
 	  If you want to execute 32-bit userspace applications, say Y.
 
-endmenu
+endmenu # "Kernel features"
 
 menu "Boot options"
 
@@ -510,7 +526,6 @@ config CMDLINE_EXTEND
 	  cases where the provided arguments are insufficient and
 	  you don't want to or cannot modify them.
 
-
 config CMDLINE_FORCE
 	bool "Always use the default kernel command string"
 	help
@@ -553,6 +568,7 @@ config STACKPROTECTOR_PER_TASK
 
 config PHYS_RAM_BASE_FIXED
 	bool "Explicitly specified physical RAM address"
+	depends on NONPORTABLE
 	default n
 
 config PHYS_RAM_BASE
@@ -566,7 +582,7 @@ config PHYS_RAM_BASE
 
 config XIP_KERNEL
 	bool "Kernel Execute-In-Place from ROM"
-	depends on MMU && SPARSEMEM
+	depends on MMU && SPARSEMEM && NONPORTABLE
 	# This prevents XIP from being enabled by all{yes,mod}config, which
 	# fail to build since XIP doesn't support large kernels.
 	depends on !COMPILE_TEST
@@ -602,23 +618,30 @@ config XIP_PHYS_ADDR
 	  be linked for and stored to.  This address is dependent on your
 	  own flash usage.
 
-endmenu
+endmenu # "Boot options"
 
 config BUILTIN_DTB
 	bool
-	depends on OF
+	depends on OF && NONPORTABLE
 	default y if XIP_KERNEL
 
+config PORTABLE
+	bool
+	default !NONPORTABLE
+	select EFI
+	select OF
+	select MMU
+
 menu "Power management options"
 
 source "kernel/power/Kconfig"
 
-endmenu
+endmenu # "Power management options"
 
 menu "CPU Power Management"
 
 source "drivers/cpuidle/Kconfig"
 
-endmenu
+endmenu # "CPU Power Management"
 
 source "arch/riscv/kvm/Kconfig"