From:   Eric Curtin <ecurtin@redhat.com>
To:     asahi@lists.linux.dev
Cc:     Eric Curtin <ecurtin@redhat.com>,
        Dan Carpenter <error27@gmail.com>,
        Hector Martin <marcan@marcan.st>,
        Sven Peter <sven@svenpeter.dev>,
        Alyssa Rosenzweig <alyssa@rosenzweig.io>,
        Joerg Roedel <joro@8bytes.org>, Will Deacon <will@kernel.org>,
        Robin Murphy <robin.murphy@arm.com>,
        linux-arm-kernel@lists.infradead.org (moderated list:ARM/APPLE MACHINE
        SUPPORT), iommu@lists.linux.dev (open list:IOMMU SUBSYSTEM),
        linux-kernel@vger.kernel.org (open list)
Subject: [PATCH v2] iommu: dart: DART_T8110_ERROR range should be 0 to 5
Date:   Wed,  1 Feb 2023 12:42:58 +0000
Message-Id: <20230201124257.7801-1-ecurtin@redhat.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

This was detected by smatch as one "else if" statement could never be
reached. Confirmed bit order by comparing with python implementation [1].

drivers/iommu/apple-dart.c:991 apple_dart_t8110_irq()
warn: duplicate check 'error_code == ((((1))) << (3))'
  (previous on line 989)

Link: https://github.com/AsahiLinux/m1n1/commit/96b2d584feec1e3f7bfa [1]

Fixes: d8bcc870d99d ("iommu: dart: Add t8110 DART support")
Reported-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Eric Curtin <ecurtin@redhat.com
---
Changes in v2: Remove DART_T8110_ERROR_ADDR_HI change
---
 drivers/iommu/apple-dart.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/iommu/apple-dart.c b/drivers/iommu/apple-dart.c
index 42666617803d..fd09abe8d29e 100644
--- a/drivers/iommu/apple-dart.c
+++ b/drivers/iommu/apple-dart.c
@@ -111,8 +111,8 @@
 
 #define DART_T8110_ERROR_MASK 0x104
 
-#define DART_T8110_ERROR_READ_FAULT BIT(4)
-#define DART_T8110_ERROR_WRITE_FAULT BIT(3)
+#define DART_T8110_ERROR_READ_FAULT BIT(5)
+#define DART_T8110_ERROR_WRITE_FAULT BIT(4)
 #define DART_T8110_ERROR_NO_PTE BIT(3)
 #define DART_T8110_ERROR_NO_PMD BIT(2)
 #define DART_T8110_ERROR_NO_PGD BIT(1)
-- 
2.39.1