Re: [PATCH] i2c: cpm: Fix i2c_ram structure

[Joakim Tjernlund <Joakim.Tjernlund@infinera.com>]

On Tue, 2020-09-22 at 11:04 +0200, nico.vince@gmail.com wrote:
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> 
> From: Nicolas VINCENT <nicolas.vincent@vossloh.com>
> 
> the i2c_ram structure is missing the sdmatmp field mentionned in
> datasheet for MPC8272 at paragraph 36.5. With this field missing, the
> hardware would write past the allocated memory done through
> cpm_muram_alloc for the i2c_ram structure and land in memory allocated
> for the buffers descriptors corrupting the cbd_bufaddr field. Since this
> field is only set during setup(), the first i2c transaction would work
> and the following would send data read from an arbitrary memory
> location.
> 
> Signed-off-by: Nicolas VINCENT <nicolas.vincent@vossloh.com>
> ---
>  drivers/i2c/busses/i2c-cpm.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/i2c/busses/i2c-cpm.c b/drivers/i2c/busses/i2c-cpm.c
> index 1213e1932ccb..c5700addbf65 100644
> --- a/drivers/i2c/busses/i2c-cpm.c
> +++ b/drivers/i2c/busses/i2c-cpm.c
> @@ -64,7 +64,8 @@ struct i2c_ram {
>         uint    txtmp;          /* Internal */
>         char    res1[4];        /* Reserved */
>         ushort  rpbase;         /* Relocation pointer */
> -       char    res2[2];        /* Reserved */
> +       char    res2[6];        /* Reserved */
> +       uint    sdmatmp;        /* Internal */
>  };

Not sure if this will fit on 8xx CPUs, Leroy ?

 Jocke