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hw/mips_malta: Fix YAMON API print routine

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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 <paul.burton@imgtec.com>
Cc: Aurelien Jarno <aurelien@aurel32.net>
Cc: Leon Alrae <leon.alrae@imgtec.com>
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Reviewed-by: Leon Alrae <leon.alrae@imgtec.com>
Signed-off-by: Leon Alrae <leon.alrae@imgtec.com>
This commit is contained in:
Paul Burton 2016-07-22 10:55:40 +01:00 committed by Leon Alrae
parent 21a21b853a
commit 7f81dbb9a0
1 changed files with 1 additions and 1 deletions
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hw/mips/mips_malta.c
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@ -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 */