Re: [PATCH 03/10] memory: define reserve_sdram_region helper

[Sascha Hauer <sha@pengutronix.de>]

On Mon, Aug 15, 2022 at 05:32:02PM +0200, Ahmad Fatoum wrote:
> We use request_sdram_regions both for code that barebox wants to use for
> itself (e.g. barebox stack or initrd) and to reserve regions for secure
> firmware that barebox shouldn't overwrite. We need to differentiate
> between them, so we can apply difference caching flags depending on

s/difference/different/

Sascha

> region, so add a new reserve_sdram_region helper that may be used and
> also add an for_each_reserved_region iterator for use in the MMU code
> that applied the different caching flags later on.
> 
> Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
> ---
>  include/memory.h | 12 ++++++++++++
>  1 file changed, 12 insertions(+)
> 
> diff --git a/include/memory.h b/include/memory.h
> index 31da5d74d568..ffd66db02ba0 100644
> --- a/include/memory.h
> +++ b/include/memory.h
> @@ -4,6 +4,7 @@
>  
>  #include <linux/types.h>
>  #include <linux/list.h>
> +#include <linux/ioport.h>
>  
>  void mem_malloc_init(void *start, void *end);
>  ulong mem_malloc_start(void);
> @@ -22,6 +23,9 @@ int barebox_add_memory_bank(const char *name, resource_size_t start,
>  				    resource_size_t size);
>  
>  #define for_each_memory_bank(mem)	list_for_each_entry(mem, &memory_banks, list)
> +#define for_each_reserved_region(mem, rsv) \
> +	list_for_each_entry(rsv, &(mem)->res->children, sibling) \
> +	if (((rsv)->flags & IORESOURCE_BUSY))
>  
>  struct resource *__request_sdram_region(const char *name, unsigned flags,
>  					resource_size_t start, resource_size_t size);
> @@ -34,6 +38,14 @@ static inline struct resource *request_sdram_region(const char *name,
>  	return __request_sdram_region(name, 0, start, size);
>  }
>  
> +/* use for secure firmware to inhibit speculation */
> +static inline struct resource *reserve_sdram_region(const char *name,
> +						    resource_size_t start,
> +						    resource_size_t size)
> +{
> +	return __request_sdram_region(name, IORESOURCE_BUSY, start, size);
> +}
> +
>  int release_sdram_region(struct resource *res);
>  
>  void memory_bank_find_space(struct memory_bank *bank, resource_size_t *retstart,
> -- 
> 2.30.2
> 
> 
> 

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