[PATCH 4/7] ARM: at91: enable the L2 Cache controller

[Alexandre Belloni]

Hi Wenyou,

This patch is not necessary, the only thing missing is the prefetch
configuration and I will submit the correct DT snippet for 3.21.

On 26/01/2015 at 18:07:16 +0800, Wenyou Yang wrote :
> Signed-off-by: Wenyou Yang <wenyou.yang at atmel.com>
> ---
>  arch/arm/mach-at91/board-dt-sama5.c |   53 +++++++++++++++++++++++++++++++++++
>  1 file changed, 53 insertions(+)
> 
> diff --git a/arch/arm/mach-at91/board-dt-sama5.c b/arch/arm/mach-at91/board-dt-sama5.c
> index 86cffcd..ed6db28 100644
> --- a/arch/arm/mach-at91/board-dt-sama5.c
> +++ b/arch/arm/mach-at91/board-dt-sama5.c
> @@ -17,17 +17,70 @@
>  #include <linux/of_platform.h>
>  #include <linux/phy.h>
>  #include <linux/clk-provider.h>
> +#include <linux/of_address.h>
>  
>  #include <asm/setup.h>
>  #include <asm/irq.h>
>  #include <asm/mach/arch.h>
>  #include <asm/mach/map.h>
>  #include <asm/mach/irq.h>
> +#include <asm/hardware/cache-l2x0.h>
>  
>  #include "generic.h"
>  
> +void __iomem *at91_l2cc_base;
> +EXPORT_SYMBOL_GPL(at91_l2cc_base);
> +
> +#ifdef CONFIG_CACHE_L2X0
> +static void __init at91_init_l2cache(void)
> +{
> +	struct device_node *np;
> +	u32 reg;
> +
> +	np = of_find_compatible_node(NULL, NULL, "arm,pl310-cache");
> +	if (!np)
> +		return;
> +
> +	at91_l2cc_base = of_iomap(np, 0);
> +	if (!at91_l2cc_base)
> +		panic("unable to map l2cc cpu registers\n");
> +
> +	of_node_put(np);
> +
> +	/* Disable cache if it hasn't been done yet */
> +	if (readl_relaxed(at91_l2cc_base + L2X0_CTRL) & L2X0_CTRL_EN)
> +		writel_relaxed(~L2X0_CTRL_EN, at91_l2cc_base + L2X0_CTRL);
> +
> +	/* Prefetch Control */
> +	reg = readl_relaxed(at91_l2cc_base + L310_PREFETCH_CTRL);
> +	reg &= ~L310_PREFETCH_CTRL_OFFSET_MASK;
> +	reg |= 0x01;
> +	reg |= L310_PREFETCH_CTRL_DBL_LINEFILL_INCR;
> +	reg |= L310_PREFETCH_CTRL_PREFETCH_DROP;
> +	reg |= L310_PREFETCH_CTRL_DATA_PREFETCH;
> +	reg |= L310_PREFETCH_CTRL_INSTR_PREFETCH;
> +	reg |= L310_PREFETCH_CTRL_DBL_LINEFILL;
> +	writel_relaxed(reg, at91_l2cc_base + L310_PREFETCH_CTRL);
> +
> +	/* Power Control */
> +	reg = readl_relaxed(at91_l2cc_base + L310_POWER_CTRL);
> +	reg |= L310_STNDBY_MODE_EN;
> +	reg |= L310_DYNAMIC_CLK_GATING_EN;
> +	writel_relaxed(reg, at91_l2cc_base + L310_POWER_CTRL);
> +
> +	/* Disable interrupts */
> +	writel_relaxed(0x00, at91_l2cc_base + L2X0_INTR_MASK);
> +	writel_relaxed(0x01ff, at91_l2cc_base + L2X0_INTR_CLEAR);
> +	l2x0_of_init(0, ~0UL);
> +}
> +#else
> +static inline void at91_init_l2cache(void) {}
> +#endif
> +
>  static void __init sama5_dt_device_init(void)
>  {
> +	at91_init_l2cache();
> +
>  	of_platform_populate(NULL, of_default_bus_match_table, NULL, NULL);
>  	at91_sam9x5_pm_init();
>  }
> -- 
> 1.7.9.5
> 

-- 
Alexandre Belloni, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com