MIPS: make inclusion of ROM exception vectors configurable
This adds a compile time option to include code for static
exception vectors. Static exception vectors are only needed,
when the U-Boot entry point is equal to the CPU reset exception
vector address. For instance this is the case when U-Boot is
used as ROM in Qemu or booted from parallel NOR flash. When
U-Boot is booted from RAM (e.g. loaded there by SPL), the
exception vectors need to be setup dynamically, which is done
in follow-up commits.
Signed-off-by: Daniel Schwierzeck <daniel.schwierzeck@gmail.com>
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index 097ad58..709ac5c 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -20,6 +20,7 @@
select SUPPORTS_CPU_MIPS32_R2
select SUPPORTS_CPU_MIPS64_R1
select SUPPORTS_CPU_MIPS64_R2
+ select ROM_EXCEPTION_VECTORS
config TARGET_MALTA
bool "Support malta"
@@ -40,6 +41,7 @@
select SUPPORTS_CPU_MIPS64_R6
select SWAP_IO_SPACE
select MIPS_L1_CACHE_SHIFT_6
+ select ROM_EXCEPTION_VECTORS
config TARGET_VCT
bool "Support vct"
@@ -47,6 +49,7 @@
select SUPPORTS_CPU_MIPS32_R1
select SUPPORTS_CPU_MIPS32_R2
select SYS_MIPS_CACHE_INIT_RAM_LOAD
+ select ROM_EXCEPTION_VECTORS
config TARGET_DBAU1X00
bool "Support dbau1x00"
@@ -55,6 +58,7 @@
select SUPPORTS_CPU_MIPS32_R1
select SUPPORTS_CPU_MIPS32_R2
select SYS_MIPS_CACHE_INIT_RAM_LOAD
+ select ROM_EXCEPTION_VECTORS
select MIPS_TUNE_4KC
config TARGET_PB1X00
@@ -63,6 +67,7 @@
select SUPPORTS_CPU_MIPS32_R1
select SUPPORTS_CPU_MIPS32_R2
select SYS_MIPS_CACHE_INIT_RAM_LOAD
+ select ROM_EXCEPTION_VECTORS
select MIPS_TUNE_4KC
config ARCH_ATH79
@@ -91,6 +96,7 @@
select SUPPORTS_CPU_MIPS64_R1
select SUPPORTS_CPU_MIPS64_R2
select SUPPORTS_CPU_MIPS64_R6
+ select ROM_EXCEPTION_VECTORS
config TARGET_XILFPGA
bool "Support Imagination Xilfpga"
@@ -103,6 +109,7 @@
select SUPPORTS_CPU_MIPS32_R1
select SUPPORTS_CPU_MIPS32_R2
select MIPS_L1_CACHE_SHIFT_4
+ select ROM_EXCEPTION_VECTORS
help
This supports IMGTEC MIPSfpga platform
@@ -192,6 +199,20 @@
endchoice
+menu "General setup"
+
+config ROM_EXCEPTION_VECTORS
+ bool "Build U-Boot image with exception vectors"
+ help
+ Enable this to include exception vectors in the U-Boot image. This is
+ required if the U-Boot entry point is equal to the address of the
+ CPU reset exception vector (e.g. U-Boot as ROM loader in Qemu,
+ U-Boot booted from parallel NOR flash).
+ Disable this, if the U-Boot image is booted from DRAM (e.g. by SPL).
+ In that case the image size will be reduced by 0x500 bytes.
+
+endmenu
+
menu "OS boot interface"
config MIPS_BOOT_CMDLINE_LEGACY
diff --git a/arch/mips/cpu/start.S b/arch/mips/cpu/start.S
index 3f0fc12..108d2df 100644
--- a/arch/mips/cpu/start.S
+++ b/arch/mips/cpu/start.S
@@ -57,7 +57,6 @@
b reset
nop
- .org 0x10
#if defined(CONFIG_SYS_XWAY_EBU_BOOTCFG)
/*
* Almost all Lantiq XWAY SoC devices have an external bus unit (EBU) to
@@ -66,16 +65,20 @@
* initial configuration for that EBU in order to access the flash
* device with correct parameters. This config option is board-specific.
*/
+ .org 0x10
.word CONFIG_SYS_XWAY_EBU_BOOTCFG
.word 0x0
-#elif defined(CONFIG_MALTA)
+#endif
+#if defined(CONFIG_MALTA)
/*
* Linux expects the Board ID here.
*/
+ .org 0x10
.word 0x00000420 # 0x420 (Malta Board with CoreLV)
.word 0x00000000
#endif
+#if defined(CONFIG_ROM_EXCEPTION_VECTORS)
.org 0x200
/* TLB refill, 32 bit task */
1: b 1b
@@ -106,7 +109,9 @@
1: b 1b
nop
+ .org 0x500
+#endif
+
- .align 4
reset:
#if __mips_isa_rev >= 6
mfc0 t0, CP0_CONFIG, 5
diff --git a/arch/mips/mach-ath79/Kconfig b/arch/mips/mach-ath79/Kconfig
index 7d483aa..d982b0f 100644
--- a/arch/mips/mach-ath79/Kconfig
+++ b/arch/mips/mach-ath79/Kconfig
@@ -9,6 +9,7 @@
select SUPPORTS_BIG_ENDIAN
select SUPPORTS_CPU_MIPS32_R1
select SUPPORTS_CPU_MIPS32_R2
+ select ROM_EXCEPTION_VECTORS
select MIPS_TUNE_24KC
help
This supports QCA/Atheros ar933x family SOCs.
@@ -27,6 +28,7 @@
select SUPPORTS_BIG_ENDIAN
select SUPPORTS_CPU_MIPS32_R1
select SUPPORTS_CPU_MIPS32_R2
+ select ROM_EXCEPTION_VECTORS
select MIPS_TUNE_24KC
help
This supports QCA/Atheros qca953x family SOCs.
diff --git a/arch/mips/mach-pic32/Kconfig b/arch/mips/mach-pic32/Kconfig
index 2e38bb7..8fad4cf 100644
--- a/arch/mips/mach-pic32/Kconfig
+++ b/arch/mips/mach-pic32/Kconfig
@@ -14,6 +14,7 @@
select SUPPORTS_CPU_MIPS32_R2
select MIPS_L1_CACHE_SHIFT_4
select SYS_MIPS_CACHE_INIT_RAM_LOAD
+ select ROM_EXCEPTION_VECTORS
help
This supports Microchip PIC32MZ[DA] family of microcontrollers.