iommu/io-pgtable-arm-v7s: Quad lvl1 pgtable for MediaTek

The standard input iova bits is 32. MediaTek quad the lvl1 pagetable
(4 * lvl1). No change for lvl2 pagetable. Then the iova bits can reach
34bit.

Signed-off-by: Yong Wu <yong.wu@mediatek.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Reviewed-by: Tomasz Figa <tfiga@chromium.org>
Link: https://lore.kernel.org/r/20210111111914.22211-14-yong.wu@mediatek.com
Signed-off-by: Will Deacon <will@kernel.org>

drivers/iommu/io-pgtable-arm-v7s.c

@@ -45,9 +45,10 @@
 /*
  * We have 32 bits total; 12 bits resolved at level 1, 8 bits at level 2,
  * and 12 bits in a page.
+ * MediaTek extend 2 bits to reach 34bits, 14 bits at lvl1 and 8 bits at lvl2.
  */
 #define ARM_V7S_ADDR_BITS		32
-#define _ARM_V7S_LVL_BITS(lvl, cfg)	((lvl) == 1 ? 12 : 8)
+#define _ARM_V7S_LVL_BITS(lvl, cfg)	((lvl) == 1 ? ((cfg)->ias - 20) : 8)
 #define ARM_V7S_LVL_SHIFT(lvl)		((lvl) == 1 ? 20 : 12)
 #define ARM_V7S_TABLE_SHIFT		10
 
@@ -61,7 +62,7 @@
 #define _ARM_V7S_IDX_MASK(lvl, cfg)	(ARM_V7S_PTES_PER_LVL(lvl, cfg) - 1)
 #define ARM_V7S_LVL_IDX(addr, lvl, cfg)	({				\
 	int _l = lvl;							\
-	((u32)(addr) >> ARM_V7S_LVL_SHIFT(_l)) & _ARM_V7S_IDX_MASK(_l, cfg); \
+	((addr) >> ARM_V7S_LVL_SHIFT(_l)) & _ARM_V7S_IDX_MASK(_l, cfg); \
 })
 
 /*
@@ -748,7 +749,7 @@ static struct io_pgtable *arm_v7s_alloc_pgtable(struct io_pgtable_cfg *cfg,
 {
 	struct arm_v7s_io_pgtable *data;
 
-	if (cfg->ias > ARM_V7S_ADDR_BITS)
+	if (cfg->ias > (arm_v7s_is_mtk_enabled(cfg) ? 34 : ARM_V7S_ADDR_BITS))
 		return NULL;
 
 	if (cfg->oas > (arm_v7s_is_mtk_enabled(cfg) ? 35 : ARM_V7S_ADDR_BITS))