drm/xe/xe2: fix 64-bit division in pte_update_size

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@arndb.de>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240226124736.1272949-3-arnd@kernel.org
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
(cherry picked from commit 1408784b599927d2f361bac6dc5170d2ee275f17)
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>

diff --git a/drivers/gpu/drm/xe/xe_migrate.c b/drivers/gpu/drm/xe/xe_migrate.c
index a66fdf2d299122d73af5072ee439df172f3cd876..ee1bb938c493487415445cd41c8b771080464522 100644 (file)
--- 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;
 
                *L0 = size;
                *L0_ofs = xe_migrate_vm_addr(pt_ofs, 0);