[Skiboot] [PATCH 1/2] platforms/ibm-fsp: Fix incorrect struct member access and comparison

[Suraj Jitindar Singh]

On 18/07/16 15:26, Suraj Jitindar Singh wrote:
> For a 1004 slot mapping bit 6 (0x40) of the P0 field represents the
> pwr_ctl bit. This code previously accessed the wrong field (power_ctl)
> which is a single bit which corresponds to the 1005 mapping (which is
> the wrong mapping), performed a bitwise and with 0x40 (which will always
> be 0), and then compared to 1 (which will also always be 0).
>
> Fix this to access the byte struct member, bitwise and with 0x40 to mask
> the power_ctl bit, and double negate to guarantee 0 or 1 result.

Fixes: Coverity Bug #97820

> Fixes: 6884fe63 ("platforms/ibm-fsp: Support PCI slot")
>
> Signed-off-by: Suraj Jitindar Singh <sjitindarsingh at gmail.com>
> Acked-by: Gavin Shan <gwshan at linux.vnet.ibm.com>
> ---
>  platforms/ibm-fsp/lxvpd.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/platforms/ibm-fsp/lxvpd.c b/platforms/ibm-fsp/lxvpd.c
> index 78e709c..72512b7 100644
> --- a/platforms/ibm-fsp/lxvpd.c
> +++ b/platforms/ibm-fsp/lxvpd.c
> @@ -207,7 +207,7 @@ static void lxvpd_parse_1004_map(struct phb *phb,
>  		s->vswitch_id     = entry->pba & 0xf;
>  		s->dev_id         = entry->sba;
>  		s->pluggable      = ((entry->p0.byte & 0x20) == 0);
> -		s->power_ctl      = ((entry->p0.power_ctl & 0x40) == 1);
> +		s->power_ctl      = !!(entry->p0.byte & 0x40);
>  		s->bus_clock      = entry->p2.bus_clock - 4;
>  		s->connector_type = entry->p2.connector_type - 5;
>  		s->card_desc      = entry->p3.byte >> 6;