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* [PATCH] can: m_can: m_can_platform: Fix iomap_read_fifo() and iomap_write_fifo()
@ 2021-09-20 12:26 Aswath Govindraju
  2021-09-20 12:27 ` Aswath Govindraju
  0 siblings, 1 reply; 4+ messages in thread
From: Aswath Govindraju @ 2021-09-20 12:26 UTC (permalink / raw)
  Cc: Lokesh Vutla, Aswath Govindraju, Chandrasekar Ramakrishnan,
	Wolfgang Grandegger, Marc Kleine-Budde, David S. Miller,
	Jakub Kicinski, Matt Kline, linux-can, netdev, linux-kernel

The read an writes from the fifo are from a buffer with various fields and
data at predefined offsets. So, they reads and writes should not be done to
the same address(or port) in case of val_count greater than 1. Therefore,
fix this by using iowrite32/ioread32 instead of ioread32_rep/iowrite32_rep.

Also, the write into fifo must be performed with an offset from the message
ram base address. Therefore, fix the base address to mram_base.

Fixes: e39381770ec9 ("can: m_can: Disable IRQs on FIFO bus errors")
Signed-off-by: Aswath Govindraju <a-govindraju@ti.com>
---
 drivers/net/can/m_can/m_can_platform.c | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/drivers/net/can/m_can/m_can_platform.c b/drivers/net/can/m_can/m_can_platform.c
index 308d4f2fff00..eee47bad0592 100644
--- a/drivers/net/can/m_can/m_can_platform.c
+++ b/drivers/net/can/m_can/m_can_platform.c
@@ -32,8 +32,13 @@ static u32 iomap_read_reg(struct m_can_classdev *cdev, int reg)
 static int iomap_read_fifo(struct m_can_classdev *cdev, int offset, void *val, size_t val_count)
 {
 	struct m_can_plat_priv *priv = cdev_to_priv(cdev);
+	void __iomem *src = priv->mram_base + offset;
 
-	ioread32_rep(priv->mram_base + offset, val, val_count);
+	while (val_count--) {
+		*(unsigned int *)val = ioread32(src);
+		val += 4;
+		src += 4;
+	}
 
 	return 0;
 }
@@ -51,8 +56,13 @@ static int iomap_write_fifo(struct m_can_classdev *cdev, int offset,
 			    const void *val, size_t val_count)
 {
 	struct m_can_plat_priv *priv = cdev_to_priv(cdev);
+	void __iomem *dst = priv->mram_base + offset;
 
-	iowrite32_rep(priv->base + offset, val, val_count);
+	while (val_count--) {
+		iowrite32(*(unsigned int *)val, dst);
+		val += 4;
+		dst += 4;
+	}
 
 	return 0;
 }
-- 
2.17.1


^ permalink raw reply related	[flat|nested] 4+ messages in thread
* [PATCH] can: m_can: m_can_platform: Fix iomap_read_fifo() and iomap_write_fifo()
@ 2021-09-20 12:33 Aswath Govindraju
  2021-10-17 20:44 ` Marc Kleine-Budde
  0 siblings, 1 reply; 4+ messages in thread
From: Aswath Govindraju @ 2021-09-20 12:33 UTC (permalink / raw)
  Cc: Lokesh Vutla, Aswath Govindraju, Chandrasekar Ramakrishnan,
	Wolfgang Grandegger, Marc Kleine-Budde, David S. Miller,
	Jakub Kicinski, Matt Kline, linux-can, netdev, linux-kernel

The read and writes from the fifo are from a buffer, with various fields
and data at predefined offsets. So, they should not be done to the same
address(or port) in case of val_count greater than 1. Therefore, fix this
by using iowrite32/ioread32 instead of ioread32_rep/iowrite32_rep.

Also, the write into fifo must be performed with an offset from the message
ram base address. Therefore, fix the base address to mram_base.

Fixes: e39381770ec9 ("can: m_can: Disable IRQs on FIFO bus errors")
Signed-off-by: Aswath Govindraju <a-govindraju@ti.com>
---
 drivers/net/can/m_can/m_can_platform.c | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/drivers/net/can/m_can/m_can_platform.c b/drivers/net/can/m_can/m_can_platform.c
index 308d4f2fff00..eee47bad0592 100644
--- a/drivers/net/can/m_can/m_can_platform.c
+++ b/drivers/net/can/m_can/m_can_platform.c
@@ -32,8 +32,13 @@ static u32 iomap_read_reg(struct m_can_classdev *cdev, int reg)
 static int iomap_read_fifo(struct m_can_classdev *cdev, int offset, void *val, size_t val_count)
 {
 	struct m_can_plat_priv *priv = cdev_to_priv(cdev);
+	void __iomem *src = priv->mram_base + offset;
 
-	ioread32_rep(priv->mram_base + offset, val, val_count);
+	while (val_count--) {
+		*(unsigned int *)val = ioread32(src);
+		val += 4;
+		src += 4;
+	}
 
 	return 0;
 }
@@ -51,8 +56,13 @@ static int iomap_write_fifo(struct m_can_classdev *cdev, int offset,
 			    const void *val, size_t val_count)
 {
 	struct m_can_plat_priv *priv = cdev_to_priv(cdev);
+	void __iomem *dst = priv->mram_base + offset;
 
-	iowrite32_rep(priv->base + offset, val, val_count);
+	while (val_count--) {
+		iowrite32(*(unsigned int *)val, dst);
+		val += 4;
+		dst += 4;
+	}
 
 	return 0;
 }
-- 
2.17.1


^ permalink raw reply related	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2021-10-17 20:44 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
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2021-09-20 12:26 [PATCH] can: m_can: m_can_platform: Fix iomap_read_fifo() and iomap_write_fifo() Aswath Govindraju
2021-09-20 12:27 ` Aswath Govindraju
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2021-09-20 12:33 Aswath Govindraju
2021-10-17 20:44 ` Marc Kleine-Budde

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