Re: [PATCH] powerpc: Fix problems with 32bit PPC's running with more than 2GB of RAM

[Benjamin Herrenschmidt <benh@kernel.crashing.org>]

On Wed, 2008-07-09 at 15:44 +0200, Stefan Roese wrote:
> This patch enables 32bit PPC's (with 36bit physical address space, e.g.
> IBM/AMCC PPC44x) to run with more than 2GB of RAM. Mostly its just
> replacing types (unsigned long -> phys_addr_t).
> 
> Tested on an AMCC Katmai with 4GB of DDR2.
> 
> Signed-off-by: Stefan Roese <sr@denx.de>

But DMAs will break no ?

Ben.

> ---
>  arch/powerpc/mm/init_32.c  |    4 ++--
>  arch/powerpc/mm/mem.c      |    8 ++++----
>  arch/powerpc/mm/mmu_decl.h |    4 ++--
>  3 files changed, 8 insertions(+), 8 deletions(-)
> 
> diff --git a/arch/powerpc/mm/init_32.c b/arch/powerpc/mm/init_32.c
> index 1952b4d..325ccdd 100644
> --- a/arch/powerpc/mm/init_32.c
> +++ b/arch/powerpc/mm/init_32.c
> @@ -56,8 +56,8 @@
>  
>  DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
>  
> -unsigned long total_memory;
> -unsigned long total_lowmem;
> +phys_addr_t total_memory;
> +phys_addr_t total_lowmem;
>  
>  phys_addr_t memstart_addr = (phys_addr_t)~0ull;
>  EXPORT_SYMBOL(memstart_addr);
> diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
> index 51f82d8..55ef772 100644
> --- a/arch/powerpc/mm/mem.c
> +++ b/arch/powerpc/mm/mem.c
> @@ -329,7 +329,7 @@ static int __init mark_nonram_nosave(void)
>  void __init paging_init(void)
>  {
>  	unsigned long total_ram = lmb_phys_mem_size();
> -	unsigned long top_of_ram = lmb_end_of_DRAM();
> +	phys_addr_t top_of_ram = lmb_end_of_DRAM();
>  	unsigned long max_zone_pfns[MAX_NR_ZONES];
>  
>  #ifdef CONFIG_PPC32
> @@ -348,10 +348,10 @@ void __init paging_init(void)
>  	kmap_prot = PAGE_KERNEL;
>  #endif /* CONFIG_HIGHMEM */
>  
> -	printk(KERN_DEBUG "Top of RAM: 0x%lx, Total RAM: 0x%lx\n",
> -	       top_of_ram, total_ram);
> +	printk(KERN_DEBUG "Top of RAM: 0x%llx, Total RAM: 0x%lx\n",
> +	       (u64)top_of_ram, total_ram);
>  	printk(KERN_DEBUG "Memory hole size: %ldMB\n",
> -	       (top_of_ram - total_ram) >> 20);
> +	       (long int)((top_of_ram - total_ram) >> 20));
>  	memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
>  #ifdef CONFIG_HIGHMEM
>  	max_zone_pfns[ZONE_DMA] = lowmem_end_addr >> PAGE_SHIFT;
> diff --git a/arch/powerpc/mm/mmu_decl.h b/arch/powerpc/mm/mmu_decl.h
> index 0480225..4e46c63 100644
> --- a/arch/powerpc/mm/mmu_decl.h
> +++ b/arch/powerpc/mm/mmu_decl.h
> @@ -49,8 +49,8 @@ extern unsigned int num_tlbcam_entries;
>  extern unsigned long ioremap_bot;
>  extern unsigned long __max_low_memory;
>  extern phys_addr_t __initial_memory_limit_addr;
> -extern unsigned long total_memory;
> -extern unsigned long total_lowmem;
> +extern phys_addr_t total_memory;
> +extern phys_addr_t total_lowmem;
>  extern phys_addr_t memstart_addr;
>  extern phys_addr_t lowmem_end_addr;
>