From 1d9e94779956b765d316924cc39af2165ad631fb Mon Sep 17 00:00:00 2001 From: Andrey Smirnov Date: Sat, 18 Jun 2016 18:09:30 -0700 Subject: [PATCH] ARM: i.MX: system.c: Tweak prefetch settings for performance Update Prefetch Control Register settings to match that of Freescale's Linux tree. As the commit e3addf1b773964eac7f797e8538c69481be4279c states (author Nitin Garg): "... set Prefetch offset to 15, since it improves memcpy performance by 35%. Don't enable Incr double Linefill enable since it adversely affects memcpy performance by about 32MB/s and reads by 90MB/s. Tested with 4K to 16MB sized src and dst aligned buffer..." Those results are also corroborated by our own testing. Acked-by: Arnd Bergmann Tested-by: Chris Healy Signed-off-by: Andrey Smirnov Signed-off-by: Shawn Guo --- arch/arm/mach-imx/system.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/arch/arm/mach-imx/system.c b/arch/arm/mach-imx/system.c index 76d7ebe..bf7ab77 100644 --- a/arch/arm/mach-imx/system.c +++ b/arch/arm/mach-imx/system.c @@ -111,8 +111,12 @@ void __init imx_init_l2cache(void) val = readl_relaxed(l2x0_base + L310_PREFETCH_CTRL); val |= L310_PREFETCH_CTRL_DBL_LINEFILL | L310_PREFETCH_CTRL_INSTR_PREFETCH | - L310_PREFETCH_CTRL_DATA_PREFETCH | - L310_PREFETCH_CTRL_DBL_LINEFILL_INCR; + L310_PREFETCH_CTRL_DATA_PREFETCH; + + /* Set perfetch offset to improve performance */ + val &= ~L310_PREFETCH_CTRL_OFFSET_MASK; + val |= 15; + writel_relaxed(val, l2x0_base + L310_PREFETCH_CTRL); } -- 2.7.4