Re: [PATCH 4/9] [SCSI] aacraid: Enable 64-bit write to controller register

[Tomas Henzl <thenzl@redhat.com>]

On 05/14/2015 02:12 AM, rajinikanth.pandurangan@pmcs.com wrote:
> From: Rajinikanth Pandurangan <rajinikanth.pandurangan@pmcs.com>
> 
> Description:
>         If writeq() not supported, then do atomic two 32bit write
> 
> Signed-off-by: Rajinikanth Pandurangan <rajinikanth.pandurangan@pmcs.com>
> ---
>  drivers/scsi/aacraid/aacraid.h  | 12 ++++++++++++
>  drivers/scsi/aacraid/comminit.c |  1 +
>  drivers/scsi/aacraid/src.c      | 12 ++++++++++--
>  3 files changed, 23 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/scsi/aacraid/aacraid.h b/drivers/scsi/aacraid/aacraid.h
> index 62b0999..9e69e3e 100644
> --- a/drivers/scsi/aacraid/aacraid.h
> +++ b/drivers/scsi/aacraid/aacraid.h
> @@ -719,6 +719,9 @@ struct sa_registers {
>  #define sa_readl(AEP, CSR)		readl(&((AEP)->regs.sa->CSR))
>  #define sa_writew(AEP, CSR, value)	writew(value, &((AEP)->regs.sa->CSR))
>  #define sa_writel(AEP, CSR, value)	writel(value, &((AEP)->regs.sa->CSR))
> +#if defined(writeq)
> +#define	sa_writeq(AEP, CSR, value)	writeq(value, &((AEP)->regs.sa->CSR))
This^ is used nowhere, is it needed?
> +#endif
>  
>  /*
>   *	Rx Message Unit Registers
> @@ -844,6 +847,10 @@ struct src_registers {
>  						&((AEP)->regs.src.bar0->CSR))
>  #define src_writel(AEP, CSR, value)	writel(value, \
>  						&((AEP)->regs.src.bar0->CSR))
> +#if defined(writeq)
> +#define	src_writeq(AEP, CSR, value)	writeq(value, \
> +						&((AEP)->regs.src.bar0->CSR))
> +#endif
>  
>  #define SRC_ODR_SHIFT		12
>  #define SRC_IDR_SHIFT		9
> @@ -1163,6 +1170,11 @@ struct aac_dev
>  	struct fsa_dev_info	*fsa_dev;
>  	struct task_struct	*thread;
>  	int			cardtype;
> +	/*
> +	 *This lock will protect the two 32-bit
> +	 *writes to the Inbound Queue
> +	 */
> +	spinlock_t		iq_lock;
>  
>  	/*
>  	 *	The following is the device specific extension.
> diff --git a/drivers/scsi/aacraid/comminit.c b/drivers/scsi/aacraid/comminit.c
> index 45a0a04..4043245 100644
> --- a/drivers/scsi/aacraid/comminit.c
> +++ b/drivers/scsi/aacraid/comminit.c
> @@ -424,6 +424,7 @@ struct aac_dev *aac_init_adapter(struct aac_dev *dev)
>  	dev->management_fib_count = 0;
>  	spin_lock_init(&dev->manage_lock);
>  	spin_lock_init(&dev->sync_lock);
> +	spin_lock_init(&dev->iq_lock);
>  	dev->max_fib_size = sizeof(struct hw_fib);
>  	dev->sg_tablesize = host->sg_tablesize = (dev->max_fib_size
>  		- sizeof(struct aac_fibhdr)
> diff --git a/drivers/scsi/aacraid/src.c b/drivers/scsi/aacraid/src.c
> index ae494c5..109863a 100644
> --- a/drivers/scsi/aacraid/src.c
> +++ b/drivers/scsi/aacraid/src.c
> @@ -447,6 +447,10 @@ static int aac_src_deliver_message(struct fib *fib)
>  	u32 fibsize;
>  	dma_addr_t address;
>  	struct aac_fib_xporthdr *pFibX;
> +#if !defined(writeq)
> +	unsigned long flags;
> +#endif
> +
>  	u16 hdr_size = le16_to_cpu(fib->hw_fib_va->header.Size);
>  
>  	atomic_inc(&q->numpending);
> @@ -511,10 +515,14 @@ static int aac_src_deliver_message(struct fib *fib)
>  			return -EINVAL;
>  		address |= fibsize;
>  	}
> -
> +#if defined(writeq)
> +	src_writeq(dev, MUnit.IQ_L, (u64)address);
What about just using the writeq directly without the macro ?
	writeq(value, address); ?
> +#else
> +	spin_lock_irqsave(&fib->dev->iq_lock, flags);
>  	src_writel(dev, MUnit.IQ_H, upper_32_bits(address) & 0xffffffff);
>  	src_writel(dev, MUnit.IQ_L, address & 0xffffffff);
> -
> +	spin_unlock_irqrestore(&fib->dev->iq_lock, flags);
> +#endif
>  	return 0;
>  }
>  
>