Re: openrisc: Consolidate setup to use memblock instead of bootmem

[Guenter Roeck <linux@roeck-us.net>]

On Wed, Apr 06, 2016 at 07:08:41PM +0900, Stafford Horne wrote:
> Clearing out one todo item. This simplifies the boot process by using
> the memblock api throughout the init process. 
> 
> The old logic bootstrapped from memblock -> bootmem -> buddy allocator
> This is now simplified by using NO_BOOTMEM. 
> 
> Signed-off-by: Stafford Horne <shorne@gmail.com>

FWIW:

Tested-by: Guenter Roeck <linux@roeck-us.net>

Guenter

> ---
>  arch/openrisc/Kconfig               |  1 +
>  arch/openrisc/TODO.openrisc         |  3 ---
>  arch/openrisc/include/asm/pgalloc.h |  1 -
>  arch/openrisc/kernel/setup.c        | 34 ++++++++++++----------------------
>  arch/openrisc/mm/init.c             |  2 +-
>  arch/openrisc/mm/ioremap.c          |  4 ----
>  6 files changed, 14 insertions(+), 31 deletions(-)
> 
> diff --git a/arch/openrisc/Kconfig b/arch/openrisc/Kconfig
> index f1030d2..e760c83 100644
> --- a/arch/openrisc/Kconfig
> +++ b/arch/openrisc/Kconfig
> @@ -27,6 +27,7 @@ config OPENRISC
>  	select HAVE_DEBUG_STACKOVERFLOW
>  	select OR1K_PIC
>  	select OMPIC if SMP
> +	select NO_BOOTMEM
>  
>  config MMU
>  	def_bool y
> diff --git a/arch/openrisc/TODO.openrisc b/arch/openrisc/TODO.openrisc
> index a2bda7b..c43d4e1 100644
> --- a/arch/openrisc/TODO.openrisc
> +++ b/arch/openrisc/TODO.openrisc
> @@ -5,9 +5,6 @@ that are due for investigation shortly, i.e. our TODO list:
>  
>  -- Implement the rest of the DMA API... dma_map_sg, etc.
>  
> --- Consolidate usage of memblock and bootmem... move everything over to
> -   memblock.
> -
>  -- Finish the renaming cleanup... there are references to or32 in the code
>     which was an older name for the architecture.  The name we've settled on is
>     or1k and this change is slowly trickling through the stack.  For the time
> diff --git a/arch/openrisc/include/asm/pgalloc.h b/arch/openrisc/include/asm/pgalloc.h
> index 21484e5b..9c9f2ba 100644
> --- a/arch/openrisc/include/asm/pgalloc.h
> +++ b/arch/openrisc/include/asm/pgalloc.h
> @@ -23,7 +23,6 @@
>  #include <linux/threads.h>
>  #include <linux/mm.h>
>  #include <linux/memblock.h>
> -#include <linux/bootmem.h>
>  
>  extern int mem_init_done;
>  
> diff --git a/arch/openrisc/kernel/setup.c b/arch/openrisc/kernel/setup.c
> index 745ff14..60f784e 100644
> --- a/arch/openrisc/kernel/setup.c
> +++ b/arch/openrisc/kernel/setup.c
> @@ -51,18 +51,16 @@
>  
>  #include "vmlinux.h"
>  
> -static unsigned long __init setup_memory(void)
> +static void __init setup_memory(void)
>  {
> -	unsigned long bootmap_size;
>  	unsigned long ram_start_pfn;
> -	unsigned long free_ram_start_pfn;
>  	unsigned long ram_end_pfn;
>  	phys_addr_t memory_start, memory_end;
>  	struct memblock_region *region;
>  
>  	memory_end = memory_start = 0;
>  
> -	/* Find main memory where is the kernel */
> +	/* Find main memory where is the kernel, we assume its the only one */
>  	for_each_memblock(memory, region) {
>  		memory_start = region->base;
>  		memory_end = region->base + region->size;
> @@ -75,10 +73,11 @@ static unsigned long __init setup_memory(void)
>  	}
>  
>  	ram_start_pfn = PFN_UP(memory_start);
> -	/* free_ram_start_pfn is first page after kernel */
> -	free_ram_start_pfn = PFN_UP(__pa(_end));
>  	ram_end_pfn = PFN_DOWN(memblock_end_of_DRAM());
>  
> +	/* setup bootmem globals (we use no_bootmem, but mm still depends on this) */
> +	min_low_pfn = ram_start_pfn;
> +	max_low_pfn = ram_end_pfn;
>  	max_pfn = ram_end_pfn;
>  
>  	/*
> @@ -86,22 +85,13 @@ static unsigned long __init setup_memory(void)
>  	 *
>  	 * This makes the memory from the end of the kernel to the end of
>  	 * RAM usable.
> -	 * init_bootmem sets the global values min_low_pfn, max_low_pfn.
>  	 */
> -	bootmap_size = init_bootmem(free_ram_start_pfn,
> -				    ram_end_pfn - ram_start_pfn);
> -	free_bootmem(PFN_PHYS(free_ram_start_pfn),
> -		     (ram_end_pfn - free_ram_start_pfn) << PAGE_SHIFT);
> -	reserve_bootmem(PFN_PHYS(free_ram_start_pfn), bootmap_size,
> -			BOOTMEM_DEFAULT);
> -
> -	for_each_memblock(reserved, region) {
> -		printk(KERN_INFO "Reserved - 0x%08x-0x%08x\n",
> -		       (u32) region->base, (u32) region->size);
> -		reserve_bootmem(region->base, region->size, BOOTMEM_DEFAULT);
> -	}
> +	memblock_reserve(__pa(_stext), _end - _stext);
> +
> +	early_init_fdt_reserve_self();
> +	early_init_fdt_scan_reserved_mem();
>  
> -	return ram_end_pfn;
> +	memblock_dump_all();
>  }
>  
>  struct cpuinfo_or1k cpuinfo_or1k[NR_CPUS];
> @@ -327,8 +317,8 @@ void __init setup_arch(char **cmdline_p)
>  	initrd_below_start_ok = 1;
>  #endif
>  
> -	/* setup bootmem allocator */
> -	max_low_pfn = setup_memory();
> +	/* setup memblock allocator */
> +	setup_memory();
>  
>  	/* paging_init() sets up the MMU and marks all pages as reserved */
>  	paging_init();
> diff --git a/arch/openrisc/mm/init.c b/arch/openrisc/mm/init.c
> index f85b73d..6972d5d 100644
> --- a/arch/openrisc/mm/init.c
> +++ b/arch/openrisc/mm/init.c
> @@ -106,7 +106,7 @@ static void __init map_ram(void)
>  			}
>  
>  			/* Alloc one page for holding PTE's... */
> -			pte = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE);
> +			pte = (pte_t *) __va(memblock_alloc(PAGE_SIZE, PAGE_SIZE));
>  			set_pmd(pme, __pmd(_KERNPG_TABLE + __pa(pte)));
>  
>  			/* Fill the newly allocated page with PTE'S */
> diff --git a/arch/openrisc/mm/ioremap.c b/arch/openrisc/mm/ioremap.c
> index 62b08ef..d11a594 100644
> --- a/arch/openrisc/mm/ioremap.c
> +++ b/arch/openrisc/mm/ioremap.c
> @@ -124,11 +124,7 @@ pte_t __init_refok *pte_alloc_one_kernel(struct mm_struct *mm,
>  	if (likely(mem_init_done)) {
>  		pte = (pte_t *) __get_free_page(GFP_KERNEL | __GFP_REPEAT);
>  	} else {
> -		pte = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE);
> -#if 0
> -		/* FIXME: use memblock... */
>  		pte = (pte_t *) __va(memblock_alloc(PAGE_SIZE, PAGE_SIZE));
> -#endif
>  	}
>  
>  	if (pte)