RE: [PATCH v1 4/7] i2c-mlxbf.c: incorrect base address passed during io write

[Asmaa Mnebhi]

Apologies, just want to clarify that I was talking about the frequency fix "[PATCH v1 1/7] i2c-mlxbf.c: Fix frequency calculation".
In regards to the below bug fix "[PATCH v1 4/7] i2c-mlxbf.c: incorrect base address passed during io write", we were lucky it works because this write:
writel(~0x0, priv->smbus->io + MLXBF_I2C_CAUSE_OR_CLEAR);
didn't have any impact on the overall functionality of the read/write transactions. Writing to smbus->io + 0x18 (aka  MLXBF_I2C_CAUSE_OR_CLEAR) corresponds to sc_low_timeout register which sets the timeout value before a read/write transaction aborts. 

-----Original Message-----
From: Asmaa Mnebhi 
Sent: Thursday, August 18, 2022 12:41 PM
To: Wolfram Sang <wsa@xxxxxxxxxx>
Cc: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>; linux-i2c@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; Khalil Blaiech <kblaiech@xxxxxxxxxx>
Subject: RE: [PATCH v1 4/7] i2c-mlxbf.c: incorrect base address passed during io write

It only worked on our first generation of BlueField (and we were lucky I think), not in BlueField-2 gen.

-----Original Message-----
From: Wolfram Sang <wsa@xxxxxxxxxx>
Sent: Thursday, August 18, 2022 12:27 PM
To: Asmaa Mnebhi <asmaa@xxxxxxxxxx>
Cc: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>; linux-i2c@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; Khalil Blaiech <kblaiech@xxxxxxxxxx>
Subject: Re: [PATCH v1 4/7] i2c-mlxbf.c: incorrect base address passed during io write

On Tue, Aug 16, 2022 at 06:54:09PM -0400, Asmaa Mnebhi wrote:
> Correct base address used during io write.

So, the driver never ever worked? Or were we lucky that it worked somehow?

> 
> Reviewed-by: Khalil Blaiech <kblaiech@xxxxxxxxxx>
> Signed-off-by: Asmaa Mnebhi <asmaa@xxxxxxxxxx>
> ---
>  drivers/i2c/busses/i2c-mlxbf.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/i2c/busses/i2c-mlxbf.c 
> b/drivers/i2c/busses/i2c-mlxbf.c index 39051c4a6db2..02ed6983c35c
> 100644
> --- a/drivers/i2c/busses/i2c-mlxbf.c
> +++ b/drivers/i2c/busses/i2c-mlxbf.c
> @@ -655,7 +655,7 @@ static int mlxbf_i2c_smbus_enable(struct mlxbf_i2c_priv *priv, u8 slave,
>  	/* Clear status bits. */
>  	writel(0x0, priv->smbus->io + MLXBF_I2C_SMBUS_MASTER_STATUS);
>  	/* Set the cause data. */
> -	writel(~0x0, priv->smbus->io + MLXBF_I2C_CAUSE_OR_CLEAR);
> +	writel(~0x0, priv->mst_cause->io + MLXBF_I2C_CAUSE_OR_CLEAR);
>  	/* Zero PEC byte. */
>  	writel(0x0, priv->smbus->io + MLXBF_I2C_SMBUS_MASTER_PEC);
>  	/* Zero byte count. */
> --
> 2.30.1
>