Feedback-ID: i51094778:Fastmail
From:   Sven Peter <sven@svenpeter.dev>
To:     Hector Martin <marcan@marcan.st>, Sven Peter <sven@svenpeter.dev>,
        Joerg Roedel <joro@8bytes.org>, Will Deacon <will@kernel.org>,
        Robin Murphy <robin.murphy@arm.com>
Cc:     Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Alyssa Rosenzweig <alyssa@rosenzweig.io>,
        linux-arm-kernel@lists.infradead.org, asahi@lists.linux.dev,
        iommu@lists.linux.dev, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: [PATCH 3/4] iommu: dart: Write to all DART_T8020_STREAM_SELECT
Date:   Sat, 28 Jan 2023 12:11:13 +0100
Message-Id: <20230128111114.4049-4-sven@svenpeter.dev>
In-Reply-To: <20230128111114.4049-1-sven@svenpeter.dev>
References: <20230128111114.4049-1-sven@svenpeter.dev>
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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.

Signed-off-by: Sven Peter <sven@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 7d8b2b90cdb6..7579c97a9062 100644
--- a/drivers/iommu/apple-dart.c
+++ b/drivers/iommu/apple-dart.c
@@ -372,12 +372,14 @@ 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(
-- 
2.25.1