microblaze: start.S: add support for configurable vector base address
Current code assumes that the vector base address is always at 0x0.
However, this value is configurable for MicroBlaze, so update the
__setup_exceptions routine to work with any vector base address.
The r4 register is reserved for the vector base address inside
__setup_exceptions and the function prologe/epilogue are also updated to
save and restore r4.
Signed-off-by: Ovidiu Panait <ovidiu.panait@windriver.com>
Link: https://lore.kernel.org/r/20211130163358.2531677-9-ovidiu.panait@windriver.com
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
diff --git a/arch/microblaze/cpu/start.S b/arch/microblaze/cpu/start.S
index 68f97f4..645f7cb 100644
--- a/arch/microblaze/cpu/start.S
+++ b/arch/microblaze/cpu/start.S
@@ -105,15 +105,17 @@
* r10: Stores little/big endian offset for vectors
* r2: Stores imm opcode
* r3: Stores brai opcode
+ * r4: Stores the vector base address
*/
__setup_exceptions:
- addik r1, r1, -28
+ addik r1, r1, -32
swi r2, r1, 4
swi r3, r1, 8
- swi r6, r1, 12
- swi r7, r1, 16
- swi r8, r1, 20
- swi r10, r1, 24
+ swi r4, r1, 12
+ swi r6, r1, 16
+ swi r7, r1, 20
+ swi r8, r1, 24
+ swi r10, r1, 28
/* Find-out if u-boot is running on BIG/LITTLE endian platform
* There are some steps which is necessary to keep in mind:
@@ -132,22 +134,25 @@
addi r2, r0, 0xb0000000 /* hex b000 opcode imm */
addi r3, r0, 0xb8080000 /* hew b808 opcode brai */
+ /* Store the vector base address in r4 */
+ addi r4, r0, CONFIG_XILINX_MICROBLAZE0_VECTOR_BASE_ADDR
+
/* reset address */
- swi r2, r0, 0x0 /* reset address - imm opcode */
- swi r3, r0, 0x4 /* reset address - brai opcode */
+ swi r2, r4, 0x0 /* reset address - imm opcode */
+ swi r3, r4, 0x4 /* reset address - brai opcode */
addik r6, r0, CONFIG_SYS_TEXT_BASE
sw r6, r1, r0
lhu r7, r1, r10
rsubi r8, r10, 0x2
- sh r7, r0, r8
+ sh r7, r4, r8
rsubi r8, r10, 0x6
- sh r6, r0, r8
+ sh r6, r4, r8
#if CONFIG_IS_ENABLED(XILINX_MICROBLAZE0_USR_EXCEP)
/* user_vector_exception */
- swi r2, r0, 0x8 /* user vector exception - imm opcode */
- swi r3, r0, 0xC /* user vector exception - brai opcode */
+ swi r2, r4, 0x8 /* user vector exception - imm opcode */
+ swi r3, r4, 0xC /* user vector exception - brai opcode */
addik r6, r5, _exception_handler
sw r6, r1, r0
@@ -173,42 +178,43 @@
*/
lhu r7, r1, r10
rsubi r8, r10, 0xa
- sh r7, r0, r8
+ sh r7, r4, r8
rsubi r8, r10, 0xe
- sh r6, r0, r8
+ sh r6, r4, r8
#endif
/* interrupt_handler */
- swi r2, r0, 0x10 /* interrupt - imm opcode */
- swi r3, r0, 0x14 /* interrupt - brai opcode */
+ swi r2, r4, 0x10 /* interrupt - imm opcode */
+ swi r3, r4, 0x14 /* interrupt - brai opcode */
addik r6, r5, _interrupt_handler
sw r6, r1, r0
lhu r7, r1, r10
rsubi r8, r10, 0x12
- sh r7, r0, r8
+ sh r7, r4, r8
rsubi r8, r10, 0x16
- sh r6, r0, r8
+ sh r6, r4, r8
/* hardware exception */
- swi r2, r0, 0x20 /* hardware exception - imm opcode */
- swi r3, r0, 0x24 /* hardware exception - brai opcode */
+ swi r2, r4, 0x20 /* hardware exception - imm opcode */
+ swi r3, r4, 0x24 /* hardware exception - brai opcode */
addik r6, r5, _hw_exception_handler
sw r6, r1, r0
lhu r7, r1, r10
rsubi r8, r10, 0x22
- sh r7, r0, r8
+ sh r7, r4, r8
rsubi r8, r10, 0x26
- sh r6, r0, r8
+ sh r6, r4, r8
- lwi r10, r1, 24
- lwi r8, r1, 20
- lwi r7, r1, 16
- lwi r6, r1, 12
+ lwi r10, r1, 28
+ lwi r8, r1, 24
+ lwi r7, r1, 20
+ lwi r6, r1, 16
+ lwi r4, r1, 12
lwi r3, r1, 8
lwi r2, r1, 4
- addik r1, r1, 28
+ addik r1, r1, 32
rtsd r15, 8
or r0, r0, r0