riscv: add run mode configuration for SPL

U-Boot SPL can be run in a different privilege mode from U-Boot proper.
Add new configuration entries for SPL to allow the run mode to be
configured independently of U-Boot proper.

Extend all uses of the CONFIG_RISCV_SMODE and CONFIG_RISCV_MMODE
configuration symbols to also cover the SPL equivalents. Ensure that
files compatible with only one privilege mode are not included in builds
targeting an incompatible privilege mode.

Signed-off-by: Lukas Auer <lukas.auer@aisec.fraunhofer.de>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index 8cfc7d0..b8d01ba 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -113,6 +113,23 @@
 
 endchoice
 
+choice
+	prompt "SPL Run Mode"
+	default SPL_RISCV_MMODE
+	depends on SPL
+
+config SPL_RISCV_MMODE
+	bool "Machine"
+	help
+	  Choose this option to build U-Boot SPL for RISC-V M-Mode.
+
+config SPL_RISCV_SMODE
+	bool "Supervisor"
+	help
+	  Choose this option to build U-Boot SPL for RISC-V S-Mode.
+
+endchoice
+
 config RISCV_ISA_C
 	bool "Emit compressed instructions"
 	default y
@@ -132,34 +149,40 @@
 
 config SIFIVE_CLINT
 	bool
-	depends on RISCV_MMODE
+	depends on RISCV_MMODE || SPL_RISCV_MMODE
 	select REGMAP
 	select SYSCON
+	select SPL_REGMAP if SPL
+	select SPL_SYSCON if SPL
 	help
 	  The SiFive CLINT block holds memory-mapped control and status registers
 	  associated with software and timer interrupts.
 
 config ANDES_PLIC
 	bool
-	depends on RISCV_MMODE
+	depends on RISCV_MMODE || SPL_RISCV_MMODE
 	select REGMAP
 	select SYSCON
+	select SPL_REGMAP if SPL
+	select SPL_SYSCON if SPL
 	help
 	  The Andes PLIC block holds memory-mapped claim and pending registers
 	  associated with software interrupt.
 
 config ANDES_PLMT
 	bool
-	depends on RISCV_MMODE
+	depends on RISCV_MMODE || SPL_RISCV_MMODE
 	select REGMAP
 	select SYSCON
+	select SPL_REGMAP if SPL
+	select SPL_SYSCON if SPL
 	help
 	  The Andes PLMT block holds memory-mapped mtime register
 	  associated with timer tick.
 
 config RISCV_RDTIME
 	bool
-	default y if RISCV_SMODE
+	default y if RISCV_SMODE || SPL_RISCV_SMODE
 	help
 	  The provides the riscv_get_time() API that is implemented using the
 	  standard rdtime instruction. This is the case for S-mode U-Boot, and
@@ -189,7 +212,7 @@
 
 config SBI_IPI
 	bool
-	default y if RISCV_SMODE
+	default y if RISCV_SMODE || SPL_RISCV_SMODE
 	depends on SMP
 
 config XIP