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[Qemu-devel] [PULL 1/2] hw/mips_malta: Fix YAMON API print routine
From: |
Leon Alrae |
Subject: |
[Qemu-devel] [PULL 1/2] hw/mips_malta: Fix YAMON API print routine |
Date: |
Fri, 29 Jul 2016 10:11:11 +0100 |
From: Paul Burton <address@hidden>
The print routine provided as part of the in-built bootloader had a bug
in that it attempted to use a jump instruction as part of a loop, but
the target has its upper bits zeroed leading to control flow
transferring to 0xb0000814 rather than the intended 0xbfc00814. Fix this
by using a branch instruction instead, which seems more fit for purpose.
A simple way to test this is to build a Linux kernel with EVA enabled &
attempt to boot it in QEMU. It will attempt to print a message
indicating the configuration mismatch but QEMU would previously
incorrectly jump & wind up printing a continuous stream of the letter E.
Signed-off-by: Paul Burton <address@hidden>
Cc: Aurelien Jarno <address@hidden>
Cc: Leon Alrae <address@hidden>
Reviewed-by: Aurelien Jarno <address@hidden>
Reviewed-by: Leon Alrae <address@hidden>
Signed-off-by: Leon Alrae <address@hidden>
---
hw/mips/mips_malta.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/hw/mips/mips_malta.c b/hw/mips/mips_malta.c
index 34d41ef..e90857e 100644
--- a/hw/mips/mips_malta.c
+++ b/hw/mips/mips_malta.c
@@ -727,7 +727,7 @@ static void write_bootloader(uint8_t *base, int64_t
run_addr,
stl_p(p++, 0x00000000); /* nop */
stl_p(p++, 0x0ff0021c); /* jal 870 */
stl_p(p++, 0x00000000); /* nop */
- stl_p(p++, 0x08000205); /* j 814 */
+ stl_p(p++, 0x1000fff9); /* b 814 */
stl_p(p++, 0x00000000); /* nop */
stl_p(p++, 0x01a00009); /* jalr t5 */
stl_p(p++, 0x01602021); /* move a0,t3
*/
--
2.7.4