diff options
Diffstat (limited to 'arch/mips/bcm47xx/prom.c')
-rw-r--r-- | arch/mips/bcm47xx/prom.c | 68 |
1 files changed, 67 insertions, 1 deletions
diff --git a/arch/mips/bcm47xx/prom.c b/arch/mips/bcm47xx/prom.c index 1a03a2f43496..1b170bf5f7f0 100644 --- a/arch/mips/bcm47xx/prom.c +++ b/arch/mips/bcm47xx/prom.c @@ -51,6 +51,8 @@ __init void bcm47xx_set_system_type(u16 chip_id) chip_id); } +static unsigned long lowmem __initdata; + static __init void prom_init_mem(void) { unsigned long mem; @@ -87,6 +89,7 @@ static __init void prom_init_mem(void) if (!memcmp(prom_init, prom_init + mem, 32)) break; } + lowmem = mem; /* Ignoring the last page when ddr size is 128M. Cached * accesses to last page is causing the processor to prefetch @@ -95,7 +98,6 @@ static __init void prom_init_mem(void) */ if (c->cputype == CPU_74K && (mem == (128 << 20))) mem -= 0x1000; - add_memory_region(0, mem, BOOT_MEM_RAM); } @@ -114,3 +116,67 @@ void __init prom_init(void) void __init prom_free_prom_memory(void) { } + +#if defined(CONFIG_BCM47XX_BCMA) && defined(CONFIG_HIGHMEM) + +#define EXTVBASE 0xc0000000 +#define ENTRYLO(x) ((pte_val(pfn_pte((x) >> _PFN_SHIFT, PAGE_KERNEL_UNCACHED)) >> 6) | 1) + +#include <asm/tlbflush.h> + +/* Stripped version of tlb_init, with the call to build_tlb_refill_handler + * dropped. Calling it at this stage causes a hang. + */ +void __cpuinit early_tlb_init(void) +{ + write_c0_pagemask(PM_DEFAULT_MASK); + write_c0_wired(0); + temp_tlb_entry = current_cpu_data.tlbsize - 1; + local_flush_tlb_all(); +} + +void __init bcm47xx_prom_highmem_init(void) +{ + unsigned long off = (unsigned long)prom_init; + unsigned long extmem = 0; + bool highmem_region = false; + + if (WARN_ON(bcm47xx_bus_type != BCM47XX_BUS_TYPE_BCMA)) + return; + + if (bcm47xx_bus.bcma.bus.chipinfo.id == BCMA_CHIP_ID_BCM4706) + highmem_region = true; + + if (lowmem != 128 << 20 || !highmem_region) + return; + + early_tlb_init(); + + /* Add one temporary TLB entry to map SDRAM Region 2. + * Physical Virtual + * 0x80000000 0xc0000000 (1st: 256MB) + * 0x90000000 0xd0000000 (2nd: 256MB) + */ + add_temporary_entry(ENTRYLO(0x80000000), + ENTRYLO(0x80000000 + (256 << 20)), + EXTVBASE, PM_256M); + + off = EXTVBASE + __pa(off); + for (extmem = 128 << 20; extmem < 512 << 20; extmem <<= 1) { + if (!memcmp(prom_init, (void *)(off + extmem), 16)) + break; + } + extmem -= lowmem; + + early_tlb_init(); + + if (!extmem) + return; + + pr_warn("Found %lu MiB of extra memory, but highmem is unsupported yet!\n", + extmem >> 20); + + /* TODO: Register extra memory */ +} + +#endif /* defined(CONFIG_BCM47XX_BCMA) && defined(CONFIG_HIGHMEM) */ |