Re: [4/4] powerpc/mpc8548: Add workaround for erratum NMG_SRIO135

[Scott Wood <scottwood@freescale.com>]

On Tue, Mar 06, 2012 at 05:10:56PM +0800, chenhui zhao wrote:
> From: chenhui zhao <chenhui.zhao@freescale.com>
> 
> Issue:
> Applications using lwarx/stwcx instructions in the core to
> compete for a software lock or semaphore with a device on
> RapidIO using read atomic set, clr, inc, or dec in a similar
> manner may falsely result in both masters seeing the lock
> as "available". This could result in data corruption as
> both masters try to modify the same piece of data protected
> by the lock.
> 
> Workaround:
> Set bits 13 and 29 of CCSR offset 0x01010 (EEBPCR register
> of the ECM) during initialization and leave them set
> indefinitely. This may slightly degrade overall system
> performance.
> 
> Refer to SRIO39 in MPC8548 errata document.
> 
> Signed-off-by: Gong Chen <g.chen@freescale.com>
> Signed-off-by: Zhao Chenhui <chenhui.zhao@freescale.com>
> Signed-off-by: Li Yang <leoli@freescale.com>
> 
> ---
> arch/powerpc/sysdev/fsl_rio.c |   44 +++++++++++++++++++++++++++++++++++++++++
>  1 files changed, 44 insertions(+), 0 deletions(-)
[snip]
> @@ -358,6 +391,17 @@ int fsl_rio_setup(struct platform_device *dev)
>  				dev->dev.of_node->full_name);
>  		return -EFAULT;
>  	}
> +
> +	/* Fix erratum NMG_SRIO135 */
> +	if (fsl_svr_is(SVR_8548) || fsl_svr_is(SVR_8548_E)) {
> +		rc = fixup_erratum_srio135(&dev->dev);
> +		if (rc) {
> +			dev_err(&dev->dev,
> +				"Failed to fix the erratum NMG_SRIO135.");
> +			return rc;
> +		}
> +	}

This needs to be respun based on the current tree.

-Scott