On Mon, Feb 26, 2024 at 01:46:38PM +0100, Arnd Bergmann wrote:
From: Arnd Bergmann <arnd@xxxxxxxx>
This function does not build on 32-bit targets when the compiler
fails to reduce DIV_ROUND_UP() into a shift:
ld.lld: error: undefined symbol: __aeabi_uldivmod
referenced by xe_migrate.c
drivers/gpu/drm/xe/xe_migrate.o:(pte_update_size) in archive vmlinux.a
There are two instances in this function. Change the first to
use an open-coded shift with the same behavior, and the second
one to a 32-bit calculation, which is sufficient here as the size
is never more than 2^32 pages (16TB).
Fixes: 237412e45390 ("drm/xe: Enable 32bits build")
Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
---
v2: use correct Fixes tag
but what about the other comment? How are we supposed to use
DIV_ROUND_UP() but then in some places (which?) have to open code it?
What compiler does this fail on?
---
drivers/gpu/drm/xe/xe_migrate.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/xe/xe_migrate.c b/drivers/gpu/drm/xe/xe_migrate.c
index a66fdf2d2991..ee1bb938c493 100644
--- a/drivers/gpu/drm/xe/xe_migrate.c
+++ b/drivers/gpu/drm/xe/xe_migrate.c
@@ -462,7 +462,7 @@ static u32 pte_update_size(struct xe_migrate *m,
} else {
/* Clip L0 to available size */
u64 size = min(*L0, (u64)avail_pts * SZ_2M);
- u64 num_4k_pages = DIV_ROUND_UP(size, XE_PAGE_SIZE);
+ u32 num_4k_pages = (size + XE_PAGE_SIZE - 1) >> XE_PTE_SHIFT;
also the commit message doesn't seem to match the patch as you are only
changing one instance.
Lucas De Marchi
*L0 = size;
*L0_ofs = xe_migrate_vm_addr(pt_ofs, 0);
--
2.39.2
