Commit c5df7f77 authored by Albert Herranz's avatar Albert Herranz Committed by Grant Likely
Browse files

powerpc: allow ioremap within reserved memory regions 



Add a flag to let a platform ioremap memory regions marked as reserved.

This flag will be used later by the Nintendo Wii support code to allow
ioremapping the I/O region sitting between MEM1 and MEM2 and marked
as reserved RAM in the patch "wii: use both mem1 and mem2 as ram".

This will no longer be needed when proper discontig memory support
for 32-bit PowerPC is added to the kernel.

Signed-off-by: default avatarAlbert Herranz <albert_herranz@yahoo.es>
Acked-by: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: default avatarGrant Likely <grant.likely@secretlab.ca>
parent de32400d

arch/powerpc/mm/init_32.c

+5 −0
Original line number Diff line number Diff line
@@ -82,6 +82,11 @@ extern struct task_struct *current_set[NR_CPUS]; 
int __map_without_bats;

int __map_without_ltlbs;



/*

 * This tells the system to allow ioremapping memory marked as reserved.

 */

int __allow_ioremap_reserved;



/* max amount of low RAM to map in */

unsigned long __max_low_memory = MAX_LOW_MEM;

arch/powerpc/mm/mmu_decl.h

+1 −0
Original line number Diff line number Diff line
@@ -115,6 +115,7 @@ extern void settlbcam(int index, unsigned long virt, phys_addr_t phys, 
extern void invalidate_tlbcam_entry(int index);



extern int __map_without_bats;

extern int __allow_ioremap_reserved;

extern unsigned long ioremap_base;

extern unsigned int rtas_data, rtas_size;

arch/powerpc/mm/pgtable_32.c

+3 −1
Original line number Diff line number Diff line
@@ -26,6 +26,7 @@ 
#include <linux/vmalloc.h>

#include <linux/init.h>

#include <linux/highmem.h>

#include <linux/lmb.h>



#include <asm/pgtable.h>

#include <asm/pgalloc.h>
@@ -191,7 +192,8 @@ __ioremap_caller(phys_addr_t addr, unsigned long size, unsigned long flags, 
	 * Don't allow anybody to remap normal RAM that we're using.

	 * mem_init() sets high_memory so only do the check after that.

	 */

	if (mem_init_done && (p < virt_to_phys(high_memory))) {

	if (mem_init_done && (p < virt_to_phys(high_memory)) &&

	    !(__allow_ioremap_reserved && lmb_is_region_reserved(p, size))) {

		printk("__ioremap(): phys addr 0x%llx is RAM lr %p\n",

		       (unsigned long long)p, __builtin_return_address(0));

		return NULL;

include/linux/lmb.h

+1 −0
Original line number Diff line number Diff line
@@ -54,6 +54,7 @@ extern u64 __init lmb_phys_mem_size(void); 
extern u64 lmb_end_of_DRAM(void);

extern void __init lmb_enforce_memory_limit(u64 memory_limit);

extern int __init lmb_is_reserved(u64 addr);

extern int lmb_is_region_reserved(u64 base, u64 size);

extern int lmb_find(struct lmb_property *res);



extern void lmb_dump_all(void);

lib/lmb.c

+6 −1
Original line number Diff line number Diff line
@@ -263,7 +263,7 @@ long __init lmb_reserve(u64 base, u64 size) 
	return lmb_add_region(_rgn, base, size);

}



long __init lmb_overlaps_region(struct lmb_region *rgn, u64 base, u64 size)

long lmb_overlaps_region(struct lmb_region *rgn, u64 base, u64 size)

{

	unsigned long i;
@@ -493,6 +493,11 @@ int __init lmb_is_reserved(u64 addr) 
	return 0;

}



int lmb_is_region_reserved(u64 base, u64 size)

{

	return lmb_overlaps_region(&lmb.reserved, base, size);

}



/*

 * Given a <base, len>, find which memory regions belong to this range.

 * Adjust the request and return a contiguous chunk.

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