[PATCH v4 2/3] iommu: dart: Write to all DART_T8020_STREAM_SELECT

Sven Peter sven at svenpeter.dev
Sun Nov 26 07:17:00 PST 2023


We're about to add support for a DART variant that use more than 16
streams and requires writing to two separate stream select registers
when issuing TLB flushes.

Acked-by: Hector Martin <marcan at marcan.st>
Signed-off-by: Sven Peter <sven at svenpeter.dev>
---
 drivers/iommu/apple-dart.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/iommu/apple-dart.c b/drivers/iommu/apple-dart.c
index ee05f4824bfa..8b6b0cdba9b5 100644
--- a/drivers/iommu/apple-dart.c
+++ b/drivers/iommu/apple-dart.c
@@ -368,12 +368,14 @@ apple_dart_t8020_hw_stream_command(struct apple_dart_stream_map *stream_map,
 			     u32 command)
 {
 	unsigned long flags;
-	int ret;
+	int ret, i;
 	u32 command_reg;
 
 	spin_lock_irqsave(&stream_map->dart->lock, flags);
 
-	writel(stream_map->sidmap[0], stream_map->dart->regs + DART_T8020_STREAM_SELECT);
+	for (i = 0; i < BITS_TO_U32(stream_map->dart->num_streams); i++)
+		writel(stream_map->sidmap[i],
+		       stream_map->dart->regs + DART_T8020_STREAM_SELECT + 4 * i);
 	writel(command, stream_map->dart->regs + DART_T8020_STREAM_COMMAND);
 
 	ret = readl_poll_timeout_atomic(
-- 
2.34.1




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