iommu/io-pgtable-arm: Add coverage for different OAS in selftest

Run selftests with different OAS values intead of hardcoding it to 48
bits.

We always keep OAS >= IAS to make the config valid for stage-2.

This can be further improved, if we split IAS/OAS configuration for
stage-1 and stage-2 (to use input sizes compatible with VA_BITS as
SMMUv3 does, or IAS > OAS which is valid for stage-1).

However, that adds more complexity, and the current change improves
coverage and makes it possible to test all concatenation cases.

Signed-off-by: Mostafa Saleh <smostafa@google.com>
Link: https://lore.kernel.org/r/20241202140604.422235-3-smostafa@google.com
Signed-off-by: Will Deacon <will@kernel.org>

diff --git a/drivers/iommu/io-pgtable-arm.c b/drivers/iommu/io-pgtable-arm.c
index 600e1f03a458645d5da3d26334ed651a1cd370b9..c1b62c7d81ba4b7aa24982e23927576a8652b413 100644 (file)
--- a/drivers/iommu/io-pgtable-arm.c
+++ b/drivers/iommu/io-pgtable-arm.c
@@ -1385,15 +1385,14 @@ static int __init arm_lpae_do_selftests(void)
                SZ_64K | SZ_512M,
        };
 
-       static const unsigned int ias[] __initconst = {
+       static const unsigned int address_size[] __initconst = {
                32, 36, 40, 42, 44, 48,
        };
 
-       int i, j, pass = 0, fail = 0;
+       int i, j, k, pass = 0, fail = 0;
        struct device dev;
        struct io_pgtable_cfg cfg = {
                .tlb = &dummy_tlb_ops,
-               .oas = 48,
                .coherent_walk = true,
                .iommu_dev = &dev,
        };
@@ -1402,15 +1401,19 @@ static int __init arm_lpae_do_selftests(void)
        set_dev_node(&dev, NUMA_NO_NODE);
 
        for (i = 0; i < ARRAY_SIZE(pgsize); ++i) {
-               for (j = 0; j < ARRAY_SIZE(ias); ++j) {
-                       cfg.pgsize_bitmap = pgsize[i];
-                       cfg.ias = ias[j];
-                       pr_info("selftest: pgsize_bitmap 0x%08lx, IAS %u\n",
-                               pgsize[i], ias[j]);
-                       if (arm_lpae_run_tests(&cfg))
-                               fail++;
-                       else
-                               pass++;
+               for (j = 0; j < ARRAY_SIZE(address_size); ++j) {
+                       /* Don't use ias > oas as it is not valid for stage-2. */
+                       for (k = 0; k <= j; ++k) {
+                               cfg.pgsize_bitmap = pgsize[i];
+                               cfg.ias = address_size[k];
+                               cfg.oas = address_size[j];
+                               pr_info("selftest: pgsize_bitmap 0x%08lx, IAS %u OAS %u\n",
+                                       pgsize[i], cfg.ias, cfg.oas);
+                               if (arm_lpae_run_tests(&cfg))
+                                       fail++;
+                               else
+                                       pass++;
+                       }
                }
        }