sunxi: boot0.h: allow RVBAR MMIO address customisation

To switch the ARMv8 Allwinner SoCs into the 64-bit AArch64 ISA, we need
to program the 64-bit start code address into an MMIO mapped register
that shadows the architectural RVBAR register.
This address is SoC specific, with just two versions out there so far.
Now a third address emerged, on a *variant* of an existing SoC (H616).

Change the boot0.h start code to make this address a Kconfig
selectable option, to allow easier maintenance.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Jernej Skrabec <jernej.skrabec@gmail.com>

diff --git a/arch/arm/include/asm/arch-sunxi/boot0.h b/arch/arm/include/asm/arch-sunxi/boot0.h
index 46b7e07..59ea75a 100644 (file)
--- a/arch/arm/include/asm/arch-sunxi/boot0.h
+++ b/arch/arm/include/asm/arch-sunxi/boot0.h
@@ -39,11 +39,8 @@
        .word   0xf57ff06f      // isb     sy
        .word   0xe320f003      // wfi
        .word   0xeafffffd      // b       @wfi
-#ifndef CONFIG_SUN50I_GEN_H6
-       .word   0x017000a0      // writeable RVBAR mapping address
-#else
-       .word   0x09010040      // writeable RVBAR mapping address
-#endif
+
+       .word   CONFIG_SUNXI_RVBAR_ADDRESS      // writable RVBAR mapping addr
 #ifdef CONFIG_SPL_BUILD
        .word   CONFIG_SPL_TEXT_BASE
 #else

diff --git a/arch/arm/mach-sunxi/Kconfig b/arch/arm/mach-sunxi/Kconfig
index 6be8a4d..71a4131 100644 (file)
--- a/arch/arm/mach-sunxi/Kconfig
+++ b/arch/arm/mach-sunxi/Kconfig
@@ -129,6 +129,18 @@ config SUNXI_SRAM_ADDRESS
        Some newer SoCs map the boot ROM at address 0 instead and move the
        SRAM to a different address.
 
+config SUNXI_RVBAR_ADDRESS
+       hex
+       depends on ARM64
+       default 0x09010040 if SUN50I_GEN_H6
+       default 0x017000a0
+       ---help---
+       The read-only RVBAR system register holds the address of the first
+       instruction to execute after a reset. Allwinner cores provide a
+       writable MMIO backing store for this register, to allow to set the
+       entry point when switching to AArch64. This store is on different
+       addresses, depending on the SoC.
+
 config SUNXI_A64_TIMER_ERRATUM
        bool