diff options
Diffstat (limited to 'arch/powerpc/mm/40x_mmu.c')
| -rw-r--r-- | arch/powerpc/mm/40x_mmu.c | 41 |
1 files changed, 33 insertions, 8 deletions
diff --git a/arch/powerpc/mm/40x_mmu.c b/arch/powerpc/mm/40x_mmu.c index 3899ea97fbd..5810967511d 100644 --- a/arch/powerpc/mm/40x_mmu.c +++ b/arch/powerpc/mm/40x_mmu.c @@ -35,6 +35,7 @@ #include <linux/init.h> #include <linux/delay.h> #include <linux/highmem.h> +#include <linux/memblock.h> #include <asm/pgalloc.h> #include <asm/prom.h> @@ -47,6 +48,7 @@ #include <asm/bootx.h> #include <asm/machdep.h> #include <asm/setup.h> + #include "mmu_decl.h" extern int __map_without_ltlbs; @@ -84,20 +86,20 @@ void __init MMU_init_hw(void) * vectors and the kernel live in real-mode. */ - mtspr(SPRN_DCCR, 0xF0000000); /* 512 MB of data space at 0x0. */ - mtspr(SPRN_ICCR, 0xF0000000); /* 512 MB of instr. space at 0x0. */ + mtspr(SPRN_DCCR, 0xFFFF0000); /* 2GByte of data space at 0x0. */ + mtspr(SPRN_ICCR, 0xFFFF0000); /* 2GByte of instr. space at 0x0. */ } #define LARGE_PAGE_SIZE_16M (1<<24) #define LARGE_PAGE_SIZE_4M (1<<22) -unsigned long __init mmu_mapin_ram(void) +unsigned long __init mmu_mapin_ram(unsigned long top) { - unsigned long v, s; + unsigned long v, s, mapped; phys_addr_t p; v = KERNELBASE; - p = PPC_MEMSTART; + p = 0; s = total_lowmem; if (__map_without_ltlbs) @@ -105,7 +107,7 @@ unsigned long __init mmu_mapin_ram(void) while (s >= LARGE_PAGE_SIZE_16M) { pmd_t *pmdp; - unsigned long val = p | _PMD_SIZE_16M | _PAGE_HWEXEC | _PAGE_HWWRITE; + unsigned long val = p | _PMD_SIZE_16M | _PAGE_EXEC | _PAGE_HWWRITE; pmdp = pmd_offset(pud_offset(pgd_offset_k(v), v), v); pmd_val(*pmdp++) = val; @@ -120,7 +122,7 @@ unsigned long __init mmu_mapin_ram(void) while (s >= LARGE_PAGE_SIZE_4M) { pmd_t *pmdp; - unsigned long val = p | _PMD_SIZE_4M | _PAGE_HWEXEC | _PAGE_HWWRITE; + unsigned long val = p | _PMD_SIZE_4M | _PAGE_EXEC | _PAGE_HWWRITE; pmdp = pmd_offset(pud_offset(pgd_offset_k(v), v), v); pmd_val(*pmdp) = val; @@ -130,5 +132,28 @@ unsigned long __init mmu_mapin_ram(void) s -= LARGE_PAGE_SIZE_4M; } - return total_lowmem - s; + mapped = total_lowmem - s; + + /* If the size of RAM is not an exact power of two, we may not + * have covered RAM in its entirety with 16 and 4 MiB + * pages. Consequently, restrict the top end of RAM currently + * allocable so that calls to the MEMBLOCK to allocate PTEs for "tail" + * coverage with normal-sized pages (or other reasons) do not + * attempt to allocate outside the allowed range. + */ + memblock_set_current_limit(mapped); + + return mapped; +} + +void setup_initial_memory_limit(phys_addr_t first_memblock_base, + phys_addr_t first_memblock_size) +{ + /* We don't currently support the first MEMBLOCK not mapping 0 + * physical on those processors + */ + BUG_ON(first_memblock_base != 0); + + /* 40x can only access 16MB at the moment (see head_40x.S) */ + memblock_set_current_limit(min_t(u64, first_memblock_size, 0x00800000)); } |