android_kernel_xiaomi_sm7250/arch/sh/mm/tlb-sh4.c
Paul Mundt d04a0f79f5 sh: Fix up extended mode TLB for SH-X2+ cores.
The extended mode TLB requires both 64-bit PTEs and a 64-bit pgprot,
correspondingly, the PGD also has to be 64-bits, so fix that up.

The kernel and user permission bits really are decoupled in early
cuts of the silicon, which means that we also have to set corresponding
kernel permissions on user pages or we end up with user pages that the
kernel simply can't touch (!).

Finally, with those things corrected, really enable MMUCR.ME and
correct the PTEA value (this simply needs to be the upper 32-bits
of the PTE, with the size and protection bit encoding).

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2007-09-21 11:57:55 +09:00

98 lines
2.4 KiB
C

/*
* arch/sh/mm/tlb-sh4.c
*
* SH-4 specific TLB operations
*
* Copyright (C) 1999 Niibe Yutaka
* Copyright (C) 2002 - 2007 Paul Mundt
*
* Released under the terms of the GNU GPL v2.0.
*/
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/io.h>
#include <asm/system.h>
#include <asm/mmu_context.h>
#include <asm/cacheflush.h>
void update_mmu_cache(struct vm_area_struct * vma,
unsigned long address, pte_t pte)
{
unsigned long flags;
unsigned long pteval;
unsigned long vpn;
/* Ptrace may call this routine. */
if (vma && current->active_mm != vma->vm_mm)
return;
#ifndef CONFIG_CACHE_OFF
{
unsigned long pfn = pte_pfn(pte);
if (pfn_valid(pfn)) {
struct page *page = pfn_to_page(pfn);
if (!test_bit(PG_mapped, &page->flags)) {
unsigned long phys = pte_val(pte) & PTE_PHYS_MASK;
__flush_wback_region((void *)P1SEGADDR(phys),
PAGE_SIZE);
__set_bit(PG_mapped, &page->flags);
}
}
}
#endif
local_irq_save(flags);
/* Set PTEH register */
vpn = (address & MMU_VPN_MASK) | get_asid();
ctrl_outl(vpn, MMU_PTEH);
pteval = pte.pte_low;
/* Set PTEA register */
#ifdef CONFIG_X2TLB
/*
* For the extended mode TLB this is trivial, only the ESZ and
* EPR bits need to be written out to PTEA, with the remainder of
* the protection bits (with the exception of the compat-mode SZ
* and PR bits, which are cleared) being written out in PTEL.
*/
ctrl_outl(pte.pte_high, MMU_PTEA);
#else
if (cpu_data->flags & CPU_HAS_PTEA)
/* TODO: make this look less hacky */
ctrl_outl(((pteval >> 28) & 0xe) | (pteval & 0x1), MMU_PTEA);
#endif
/* Set PTEL register */
pteval &= _PAGE_FLAGS_HARDWARE_MASK; /* drop software flags */
#ifdef CONFIG_CACHE_WRITETHROUGH
pteval |= _PAGE_WT;
#endif
/* conveniently, we want all the software flags to be 0 anyway */
ctrl_outl(pteval, MMU_PTEL);
/* Load the TLB */
asm volatile("ldtlb": /* no output */ : /* no input */ : "memory");
local_irq_restore(flags);
}
void local_flush_tlb_one(unsigned long asid, unsigned long page)
{
unsigned long addr, data;
/*
* NOTE: PTEH.ASID should be set to this MM
* _AND_ we need to write ASID to the array.
*
* It would be simple if we didn't need to set PTEH.ASID...
*/
addr = MMU_UTLB_ADDRESS_ARRAY | MMU_PAGE_ASSOC_BIT;
data = page | asid; /* VALID bit is off */
jump_to_P2();
ctrl_outl(data, addr);
back_to_P1();
}