[RFC PATCH] ARM: cache-l2x0: add setup entry for l2 in non-secure mode

[Barry Song]

2014-05-15 13:39 GMT+08:00 Gioh Kim <gioh.kim at lge.com>:
>
> Hi,
>
> My board is using Trustzone and running kernel is non-secure mode.
> But setup function of PL310 driver is only for secure mode kernel.
>
> What about adding an entry for non-secure mode setup function?
>
> I'm sorry for my poor code but I just wanna say what I need .

Gioh,

i don't really understand what is the user scenarios for this, if you
are running linux in non-secure mode, your security-mode codes have
enabled L2, so this makes non-secure linux have no chance to execute
setup at all:
 992         /* L2 configuration can only be changed if the cache is disabled */
 993         if (!(readl_relaxed(l2x0_base + L2X0_CTRL) & L2X0_CTRL_EN)) {
 994                 if (data->setup)
 995                         data->setup(np, &aux_val, &aux_mask);

anyway, cache-l2x0.c supported non-secure linux as you can read:
 387         /*
 388          * Check if l2x0 controller is already enabled.
 389          * If you are booting from non-secure mode
 390          * accessing the below registers will fault.
 391          */
 392         if (!(readl_relaxed(l2x0_base + L2X0_CTRL) & L2X0_CTRL_EN)) {
 393                 /* Make sure that I&D is not locked down when starting */
 394                 l2x0_unlock(cache_id);
 395
 396                 /* l2x0 controller is disabled */
 397                 writel_relaxed(aux, l2x0_base + L2X0_AUX_CTRL);
 398
 399                 l2x0_inv_all();
 400
 401                 /* enable L2X0 */
 402                 writel_relaxed(L2X0_CTRL_EN, l2x0_base + L2X0_CTRL);
 403         }



>
> ------------------------------ 8< -------------------------------
> From ee4b03fb2c12038c6bbb9f752558abae8d500c07 Mon Sep 17 00:00:00 2001
> From: Gioh Kim <gioh.kim at lge.com>
> Date: Thu, 15 May 2014 14:06:36 +0900
> Subject: [PATCH] ARM: cache-l2x0: add setup entry for l2 in non-secure mode
>
> For some platforms using Trustzone and running kernel in non-secure mode,
> another l2 setup function is necessary.
>
> Signed-off-by: Gioh Kim <gioh.kim at lge.c>
> ---
>  arch/arm/include/asm/hardware/cache-l2x0.h |    9 +++++++++
>  arch/arm/mm/cache-l2x0.c                   |   26 +++++++++++++++++++++++++-
>  2 files changed, 34 insertions(+), 1 deletion(-)
>
> diff --git a/arch/arm/include/asm/hardware/cache-l2x0.h b/arch/arm/include/asm/hardware/cache-l2x0.h
> index 6dec6da..de31114 100644
> --- a/arch/arm/include/asm/hardware/cache-l2x0.h
> +++ b/arch/arm/include/asm/hardware/cache-l2x0.h
> @@ -21,6 +21,7 @@
>  #define __ASM_ARM_HARDWARE_L2X0_H
>
>  #include <linux/errno.h>
> +#include <linux/of.h>
>
>  #define L2X0_CACHE_ID                  0x000
>  #define L2X0_CACHE_TYPE                        0x004
> @@ -110,11 +111,19 @@
>  extern void __init l2x0_init(void __iomem *base, u32 aux_val, u32 aux_mask);
>  #if defined(CONFIG_CACHE_L2X0) && defined(CONFIG_OF)
>  extern int l2x0_of_init(u32 aux_val, u32 aux_mask);
> +extern int l2x0_of_set_setup_nonsecure(const char *compatible, size_t len,
> +                       void (*fp)(const struct device_node *, u32 *, u32 *));
>  #else
>  static inline int l2x0_of_init(u32 aux_val, u32 aux_mask)
>  {
>         return -ENODEV;
>  }
> +static inline int l2x0_of_set_setup_nonsecure(const char *compatible,
> +                                             size_t len,
> +                     void (*fp)(const struct device_node *, u32 *, u32 *))
> +{
> +       return -ENODEV;
> +}
>  #endif
>
>  struct l2x0_regs {
> diff --git a/arch/arm/mm/cache-l2x0.c b/arch/arm/mm/cache-l2x0.c
> index 728d644..582ea37 100644
> --- a/arch/arm/mm/cache-l2x0.c
> +++ b/arch/arm/mm/cache-l2x0.c
> @@ -45,6 +45,7 @@ struct l2x0_regs l2x0_saved_regs;
>  struct l2x0_of_data {
>         void (*setup)(const struct device_node *, u32 *, u32 *);
>         void (*save)(void);
> +       void (*setup_nonsecure)(const struct device_node *, u32 *, u32 *);
>         struct outer_cache_fns outer_cache;
>  };
>
> @@ -968,6 +969,23 @@ static const struct of_device_id l2x0_ids[] __initconst = {
>         {}
>  };
>
> +int l2x0_of_set_setup_nonsecure(const char *compatible, size_t len,
> +                       void (*fp)(const struct device_node *, u32 *, u32 *))
> +{
> +       const struct of_device_id *id;
> +
> +       for (id = &l2x0_ids[0]; id->compatible != NULL; id++) {
> +               if (strncmp(id->compatible, compatible, len) == 0) {
> +                       struct l2x0_of_data *data = id->data;
> +
> +                       data->setup_nonsecure = fp;
> +                       return 0;
> +               }
> +       }
> +
> +       return -EINVAL;
> +}
> +
>  int __init l2x0_of_init(u32 aux_val, u32 aux_mask)
>  {
>         struct device_node *np;
> @@ -989,8 +1007,14 @@ int __init l2x0_of_init(u32 aux_val, u32 aux_mask)
>
>         /* L2 configuration can only be changed if the cache is disabled */
>         if (!(readl_relaxed(l2x0_base + L2X0_CTRL) & L2X0_CTRL_EN)) {
> -               if (data->setup)
> +
> +               if (data->setup_nonsecure)
> +                       data->setup_nonsecure(np, &aux_val, &aux_mask);
> +               else if (data->setup)
>                         data->setup(np, &aux_val, &aux_mask);
> +               else
> +                       /* no function to enable cache */
> +                       return -ENODEV;
>
>                 /* For aurora cache in no outer mode select the
>                  * correct mode using the coprocessor*/
> --
> 1.7.9.5


-barry