[PATCH v5 11/22] MIPS: traps: Enhance memblock ebase allocation process

From: Gregory CLEMENT
Date: Tue Dec 12 2023 - 11:36:17 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 a6d0ae12b3c4c..089247555c752 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