[RFC PATCH 06/12] arm: msm: set L2CR1 to enable prefetch and burst on Scorpion.

[Nicolas Pitre]

On Thu, 28 Jan 2010, Daniel Walker wrote:

> From: Larry Bassel <lbassel at quicinc.com>
> 
> This change improves the following LMBench benchmarks
> by over 15%:
> 
> System Call Latency
> Signal Handling Latency
> Fault Latency
> Inter-process Communication Latency
> Inter-process Communication Bandwidth
> Random Number Generation Latency
> 
> Acked-by: Steve Muckle <smuckle at quicinc.com>
> Cc: Catalin Marinas <catalin.marinas at arm.com>
> Cc: Shilimkar, Santosh <santosh.shilimkar at ti.com>
> Cc: Nicolas Pitre <nico at fluxnic.net>
> Cc: Bohan, Michael <mbohan at quicinc.com>
> Signed-off-by: Larry Bassel <lbassel at quicinc.com>
> Signed-off-by: Daniel Walker <dwalker at codeaurora.org>
> ---
>  arch/arm/mm/proc-v7.S |    5 +++++
>  1 files changed, 5 insertions(+), 0 deletions(-)
> 
> diff --git a/arch/arm/mm/proc-v7.S b/arch/arm/mm/proc-v7.S
> index 7aaf88a..3ca5d29 100644
> --- a/arch/arm/mm/proc-v7.S
> +++ b/arch/arm/mm/proc-v7.S
> @@ -2,6 +2,7 @@
>   *  linux/arch/arm/mm/proc-v7.S
>   *
>   *  Copyright (C) 2001 Deep Blue Solutions Ltd.
> + *  Copyright (c) 2009, Code Aurora Forum. All rights reserved.

Do you really think the addition of only 4 lines in a file that contains 
348 lines justifies the addition of such copyright notice?  What would 
the kernel source looks like if everyone adding/modifying 4 lines in 
every random files did the same?

Just a thought.

>   * This program is free software; you can redistribute it and/or modify
>   * it under the terms of the GNU General Public License version 2 as
> @@ -242,6 +243,10 @@ __v7_setup:
>  	mcr	p15, 0, r4, c2, c0, 1		@ load TTB1
>  	mov	r10, #0x1f			@ domains 0, 1 = manager
>  	mcr	p15, 0, r10, c3, c0, 0		@ load domain access register
> +#ifdef CONFIG_ARCH_MSM_SCORPION
> +	mov     r0, #0x77
> +	mcr     p15, 3, r0, c15, c0, 3          @ set L2CR1
> +#endif
>  	/*
>  	 * Memory region attributes with SCTLR.TRE=1
>  	 *
> -- 
> 1.6.3.3
>