[PATCH v4 11/22] MIPS: traps: Enhance memblock ebase allocation process

From: Gregory CLEMENT
Date: Fri Dec 08 2023 - 11:13:33 EST


From: Jiaxun Yang <jiaxun.yang@xxxxxxxxxxx>

We try to allocate from KSEG0 accessible space first, and
then if we really can't allocate any memory from KSEG0 and
we are sure that we support ebase in higher segment, give
it another go without restriction.

This can maximize the possibility of having ebase in KSEG0.

Signed-off-by: Jiaxun Yang <jiaxun.yang@xxxxxxxxxxx>
---
arch/mips/kernel/traps.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c
index b6e94654f6211..68f1dd54cde1c 100644
--- a/arch/mips/kernel/traps.c
+++ b/arch/mips/kernel/traps.c
@@ -2399,7 +2399,12 @@ void __init trap_init(void)
memblock_reserve(ebase_pa, vec_size);
} else {
vec_size = max(vec_size, PAGE_SIZE);
- ebase_pa = memblock_phys_alloc(vec_size, 1 << fls(vec_size));
+ ebase_pa = memblock_phys_alloc_range(vec_size, 1 << fls(vec_size),
+ 0x0, KSEGX_SIZE - 1);
+
+ if (!ebase_pa && (IS_ENABLED(CONFIG_EVA) || cpu_has_ebase_wg))
+ ebase_pa = memblock_phys_alloc(vec_size, 1 << fls(vec_size));
+
if (!ebase_pa)
panic("%s: Failed to allocate %lu bytes align=0x%x\n",
__func__, vec_size, 1 << fls(vec_size));
--
2.42.0