[PATCH net-next 13/14] mlxsw: spectrum_router: Encode adjacency group size ranges in an array

[Ido Schimmel]

From: Ido Schimmel <ido...@nvidia.com>

The device supports a fixed set of adjacency group sizes. Encode these
sizes in an array, so that the next patch will be able to split it
between Spectrum-1 and Spectrum-{2,3}, which support different size
ranges.

Signed-off-by: Ido Schimmel <ido...@nvidia.com>
Reviewed-by: Petr Machata <pe...@nvidia.com>
---
 .../ethernet/mellanox/mlxsw/spectrum_router.c | 65 +++++++++++++------
 1 file changed, 44 insertions(+), 21 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c 
b/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c
index dd3fb5ca5c32..a142d6d3e77d 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c
@@ -3559,34 +3559,57 @@ mlxsw_sp_nexthop_fib_entries_update(struct mlxsw_sp 
*mlxsw_sp,
        return 0;
 }
 
+struct mlxsw_sp_adj_grp_size_range {
+       u16 start; /* Inclusive */
+       u16 end; /* Inclusive */
+};
+
+/* Ordered by range start value */
+static const struct mlxsw_sp_adj_grp_size_range
+mlxsw_sp_adj_grp_size_ranges[] = {
+       { .start = 1, .end = 64 },
+       { .start = 512, .end = 512 },
+       { .start = 1024, .end = 1024 },
+       { .start = 2048, .end = 2048 },
+       { .start = 4096, .end = 4096 },
+};
+
 static void mlxsw_sp_adj_grp_size_round_up(u16 *p_adj_grp_size)
 {
-       /* Valid sizes for an adjacency group are:
-        * 1-64, 512, 1024, 2048 and 4096.
-        */
-       if (*p_adj_grp_size <= 64)
-               return;
-       else if (*p_adj_grp_size <= 512)
-               *p_adj_grp_size = 512;
-       else if (*p_adj_grp_size <= 1024)
-               *p_adj_grp_size = 1024;
-       else if (*p_adj_grp_size <= 2048)
-               *p_adj_grp_size = 2048;
-       else
-               *p_adj_grp_size = 4096;
+       int i;
+
+       for (i = 0; i < ARRAY_SIZE(mlxsw_sp_adj_grp_size_ranges); i++) {
+               const struct mlxsw_sp_adj_grp_size_range *size_range;
+
+               size_range = &mlxsw_sp_adj_grp_size_ranges[i];
+
+               if (*p_adj_grp_size >= size_range->start &&
+                   *p_adj_grp_size <= size_range->end)
+                       return;
+
+               if (*p_adj_grp_size <= size_range->end) {
+                       *p_adj_grp_size = size_range->end;
+                       return;
+               }
+       }
 }
 
 static void mlxsw_sp_adj_grp_size_round_down(u16 *p_adj_grp_size,
                                             unsigned int alloc_size)
 {
-       if (alloc_size >= 4096)
-               *p_adj_grp_size = 4096;
-       else if (alloc_size >= 2048)
-               *p_adj_grp_size = 2048;
-       else if (alloc_size >= 1024)
-               *p_adj_grp_size = 1024;
-       else if (alloc_size >= 512)
-               *p_adj_grp_size = 512;
+       size_t arr_size = ARRAY_SIZE(mlxsw_sp_adj_grp_size_ranges);
+       int i;
+
+       for (i = arr_size - 1; i >= 0; i--) {
+               const struct mlxsw_sp_adj_grp_size_range *size_range;
+
+               size_range = &mlxsw_sp_adj_grp_size_ranges[i];
+
+               if (alloc_size >= size_range->end) {
+                       *p_adj_grp_size = size_range->end;
+                       return;
+               }
+       }
 }
 
 static int mlxsw_sp_fix_adj_grp_size(struct mlxsw_sp *mlxsw_sp,
-- 
2.29.2