Re: [PATCH 1/2] scsi: pm80xx: mask and unmask upper interrupt vectors 32-63

[Damien Le Moal <damien.lemoal@opensource.wdc.com>]

On 3/28/22 17:42, Ajish Koshy wrote:
> When upper inbound and outbound queues 32-63 are enabled, we see upper
> vectors 32-63 in interrupt service routine. We need corresponding
> registers to handle masking and unmasking of these upper interrupts.
> 
> To achieve this, we use registers MSGU_ODMR_U(0x34) to mask and
> MSGU_ODMR_CLR_U(0x3C) to unmask the interrupts. In these registers bit
> 0-31 represents interrupt vectors 32-63.
> 
> Signed-off-by: Ajish Koshy <Ajish.Koshy@microchip.com>
> Signed-off-by: Viswas G <Viswas.G@microchip.com>
> ---
>  drivers/scsi/pm8001/pm80xx_hwi.c | 35 +++++++++++++++++++++++++++-----
>  1 file changed, 30 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/scsi/pm8001/pm80xx_hwi.c b/drivers/scsi/pm8001/pm80xx_hwi.c
> index 9bb31f66db85..b92e82a576e3 100644
> --- a/drivers/scsi/pm8001/pm80xx_hwi.c
> +++ b/drivers/scsi/pm8001/pm80xx_hwi.c
> @@ -1728,9 +1728,20 @@ pm80xx_chip_interrupt_enable(struct pm8001_hba_info *pm8001_ha, u8 vec)
>  {
>  #ifdef PM8001_USE_MSIX
>  	u32 mask;
> -	mask = (u32)(1 << vec);
> +	u32 vec_u;
>  
> -	pm8001_cw32(pm8001_ha, 0, MSGU_ODMR_CLR, (u32)(mask & 0xFFFFFFFF));
> +	if (vec < 32) {
> +		mask = (u32)(1 << vec);
> +		/*vectors 0 - 31*/
> +		pm8001_cw32(pm8001_ha, 0, MSGU_ODMR_CLR,
> +			    (u32)(mask & 0xFFFFFFFF));
> +	} else {
> +		vec_u = vec - 32;
> +		mask = (u32)(1 << vec_u);
> +		/*vectors 32 - 63*/
> +		pm8001_cw32(pm8001_ha, 0, MSGU_ODMR_CLR_U,
> +			    (u32)(mask & 0xFFFFFFFF));
> +	}
>  	return;
>  #endif
>  	pm80xx_chip_intx_interrupt_enable(pm8001_ha);
> @@ -1747,11 +1758,25 @@ pm80xx_chip_interrupt_disable(struct pm8001_hba_info *pm8001_ha, u8 vec)
>  {
>  #ifdef PM8001_USE_MSIX
>  	u32 mask;
> -	if (vec == 0xFF)
> +	u32 vec_u;
> +
> +	if (vec == 0xFF) {
>  		mask = 0xFFFFFFFF;
> -	else
> +		/* disable all vectors 0-31, 32-63*/
> +		pm8001_cw32(pm8001_ha, 0, MSGU_ODMR, mask);
> +		pm8001_cw32(pm8001_ha, 0, MSGU_ODMR_U, mask);
> +	} else if (vec < 32) {
>  		mask = (u32)(1 << vec);
> -	pm8001_cw32(pm8001_ha, 0, MSGU_ODMR, (u32)(mask & 0xFFFFFFFF));
> +		/*vectors 0 - 31*/
> +		pm8001_cw32(pm8001_ha, 0, MSGU_ODMR,
> +			    (u32)(mask & 0xFFFFFFFF));

mask is a u32, so the "& 0xFFFFFFFF" seems to be completely pointless...
And pm8001_cw32() takes a u32 value as last argument so the cast is also
pointless.

> +	} else {
> +		vec_u = vec - 32;
> +		mask = (u32)(1 << vec_u);

Cast not needed and this should probably be "1U << vec_u".
Also, the vec_u variable seems completely unnecessary.

> +		/*vectors 32 - 63*/
> +		pm8001_cw32(pm8001_ha, 0, MSGU_ODMR_U,
> +			    (u32)(mask & 0xFFFFFFFF));

Same here: The cast and masking are not needed.

> +	}
>  	return;
>  #endif
>  	pm80xx_chip_intx_interrupt_disable(pm8001_ha);


-- 
Damien Le Moal
Western Digital Research