Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit f637a49e authored by Benjamin Herrenschmidt's avatar Benjamin Herrenschmidt
Browse files

powerpc: Minor cleanups of kernel virt address space definitions 



Make FIXADDR_TOP a compile time constant and cleanup a
couple of definitions relative to the layout of the kernel
address space on ppc32. We also print out that layout at
boot time for debugging purposes.

This is a pre-requisite for properly fixing non-coherent
DMA allocactions.

Signed-off-by: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
parent b16e7766

arch/powerpc/include/asm/fixmap.h

+2 −2
Original line number Diff line number Diff line
@@ -14,8 +14,6 @@ 
#ifndef _ASM_FIXMAP_H

#define _ASM_FIXMAP_H



extern unsigned long FIXADDR_TOP;



#ifndef __ASSEMBLY__

#include <linux/kernel.h>

#include <asm/page.h>
@@ -24,6 +22,8 @@ extern unsigned long FIXADDR_TOP; 
#include <asm/kmap_types.h>

#endif



#define FIXADDR_TOP	((unsigned long)(-PAGE_SIZE))



/*

 * Here we define all the compile-time 'special' virtual

 * addresses. The point is to have a constant address at

arch/powerpc/include/asm/pgtable-ppc32.h

+20 −2
Original line number Diff line number Diff line
@@ -10,7 +10,7 @@ 


extern unsigned long va_to_phys(unsigned long address);

extern pte_t *va_to_pte(unsigned long address);

extern unsigned long ioremap_bot, ioremap_base;

extern unsigned long ioremap_bot;



#ifdef CONFIG_44x

extern int icache_44x_need_flush;
@@ -55,9 +55,27 @@ extern int icache_44x_need_flush; 
#define pgd_ERROR(e) \

	printk("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, pgd_val(e))



/*

 * This is the bottom of the PKMAP area with HIGHMEM or an arbitrary

 * value (for now) on others, from where we can start layout kernel

 * virtual space that goes below PKMAP and FIXMAP

 */

#ifdef CONFIG_HIGHMEM

#define KVIRT_TOP	PKMAP_BASE

#else

#define KVIRT_TOP	(0xfe000000UL)	/* for now, could be FIXMAP_BASE ? */

#endif



/*

 * ioremap_bot starts at that address. Early ioremaps move down from there,

 * until mem_init() at which point this becomes the top of the vmalloc

 * and ioremap space

 */

#define IOREMAP_TOP	KVIRT_TOP



/*

 * Just any arbitrary offset to the start of the vmalloc VM area: the

 * current 64MB value just means that there will be a 64MB "hole" after the

 * current 16MB value just means that there will be a 64MB "hole" after the

 * physical memory until the kernel virtual memory starts.  That means that

 * any out-of-bounds memory accesses will hopefully be caught.

 * The vmalloc() routines leaves a hole of 4kB between each vmalloced

arch/powerpc/mm/init_32.c

+2 −6
Original line number Diff line number Diff line
@@ -168,12 +168,8 @@ void __init MMU_init(void) 
		ppc_md.progress("MMU:mapin", 0x301);

	mapin_ram();



#ifdef CONFIG_HIGHMEM

	ioremap_base = PKMAP_BASE;

#else

	ioremap_base = 0xfe000000UL;	/* for now, could be 0xfffff000 */

#endif /* CONFIG_HIGHMEM */

	ioremap_bot = ioremap_base;

	/* Initialize early top-down ioremap allocator */

	ioremap_bot = IOREMAP_TOP;



	/* Map in I/O resources */

	if (ppc_md.progress)

arch/powerpc/mm/mem.c

+13 −0
Original line number Diff line number Diff line
@@ -380,6 +380,19 @@ void __init mem_init(void) 
		bsssize >> 10,

		initsize >> 10);



#ifdef CONFIG_PPC32

	pr_info("Kernel virtual memory layout:\n");

	pr_info("  * 0x%08lx..0x%08lx  : fixmap\n", FIXADDR_START, FIXADDR_TOP);

#ifdef CONFIG_HIGHMEM

	pr_info("  * 0x%08lx..0x%08lx  : highmem PTEs\n",

		PKMAP_BASE, PKMAP_ADDR(LAST_PKMAP));

#endif /* CONFIG_HIGHMEM */

	pr_info("  * 0x%08lx..0x%08lx  : early ioremap\n",

		ioremap_bot, IOREMAP_TOP);

	pr_info("  * 0x%08lx..0x%08lx  : vmalloc & ioremap\n",

		VMALLOC_START, VMALLOC_END);

#endif /* CONFIG_PPC32 */



	mem_init_done = 1;

}

arch/powerpc/mm/pgtable_32.c

+0 −2
Original line number Diff line number Diff line
@@ -399,8 +399,6 @@ void kernel_map_pages(struct page *page, int numpages, int enable) 
#endif /* CONFIG_DEBUG_PAGEALLOC */



static int fixmaps;

unsigned long FIXADDR_TOP = (-PAGE_SIZE);

EXPORT_SYMBOL(FIXADDR_TOP);



void __set_fixmap (enum fixed_addresses idx, phys_addr_t phys, pgprot_t flags)

{