source: mainline/kernel/arch/sparc64/src/mm/sun4u/as.c

/*
 * Copyright (c) 2006 Jakub Jermar
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/** @addtogroup kernel_sparc64_mm
 * @{
 */
/** @file
 */

#include <arch/mm/as.h>
#include <arch/mm/tlb.h>
#include <assert.h>
#include <config.h>
#include <genarch/mm/page_ht.h>
#include <genarch/mm/asid_fifo.h>

#ifdef CONFIG_TSB

#include <arch/mm/tsb.h>
#include <arch/asm.h>
#include <mm/frame.h>
#include <bitops.h>
#include <macros.h>
#include <memw.h>

#endif /* CONFIG_TSB */

/** Architecture dependent address space init. */
void as_arch_init(void)
{
        if (config.cpu_active == 1) {
                as_operations = &as_ht_operations;
                asid_fifo_init();
        }
}

errno_t as_constructor_arch(as_t *as, unsigned int flags)
{
#ifdef CONFIG_TSB
        uintptr_t tsb_base = frame_alloc(TSB_FRAMES, FRAME_LOWMEM | flags,
            TSB_SIZE - 1);
        if (!tsb_base)
                return ENOMEM;

        tsb_entry_t *tsb = (tsb_entry_t *) PA2KA(tsb_base);
        memsetb(tsb, TSB_SIZE, 0);

        as->arch.itsb = tsb;
        as->arch.dtsb = tsb + ITSB_ENTRY_COUNT;
#endif

        return EOK;
}

int as_destructor_arch(as_t *as)
{
#ifdef CONFIG_TSB
        frame_free(KA2PA((uintptr_t) as->arch.itsb), TSB_FRAMES);

        return TSB_FRAMES;
#else
        return 0;
#endif
}

errno_t as_create_arch(as_t *as, unsigned int flags)
{
#ifdef CONFIG_TSB
        tsb_invalidate(as, 0, (size_t) -1);
#endif

        return 0;
}

/** Perform sparc64-specific tasks when an address space becomes active on the
 * processor.
 *
 * Install ASID and map TSBs.
 *
 * @param as Address space.
 */
void as_install_arch(as_t *as)
{
        tlb_context_reg_t ctx;

        /*
         * Note that we don't and may not lock the address space. That's ok
         * since we only read members that are currently read-only.
         *
         * Moreover, the as->asid is protected by asidlock, which is being held.
         *
         */

        /*
         * Write ASID to secondary context register. The primary context
         * register has to be set from TL>0 so it will be filled from the
         * secondary context register from the TL=1 code just before switch to
         * userspace.
         *
         */
        ctx.v = 0;
        ctx.context = as->asid;
        mmu_secondary_context_write(ctx.v);

#ifdef CONFIG_TSB
        uintptr_t base = ALIGN_DOWN(config.base, 1 << KERNEL_PAGE_WIDTH);

        assert(as->arch.itsb);
        assert(as->arch.dtsb);

        uintptr_t tsb = (uintptr_t) as->arch.itsb;

        if (!overlaps(tsb, TSB_SIZE, base, 1 << KERNEL_PAGE_WIDTH)) {
                /*
                 * TSBs were allocated from memory not covered
                 * by the locked 4M kernel DTLB entry. We need
                 * to map both TSBs explicitly.
                 *
                 */
                dtlb_demap(TLB_DEMAP_PAGE, TLB_DEMAP_NUCLEUS, tsb);
                dtlb_insert_mapping(tsb, KA2PA(tsb), PAGESIZE_64K, true, true);
        }

        /*
         * Setup TSB Base registers.
         *
         */
        tsb_base_reg_t tsb_base_reg;

        tsb_base_reg.value = 0;
        tsb_base_reg.size = TSB_BASE_REG_SIZE;
        tsb_base_reg.split = 0;

        tsb_base_reg.base = ((uintptr_t) as->arch.itsb) >> MMU_PAGE_WIDTH;
        itsb_base_write(tsb_base_reg.value);
        tsb_base_reg.base = ((uintptr_t) as->arch.dtsb) >> MMU_PAGE_WIDTH;
        dtsb_base_write(tsb_base_reg.value);

#if defined (US3)
        /*
         * Clear the extension registers.
         * In HelenOS, primary and secondary context registers contain
         * equal values and kernel misses (context 0, ie. the nucleus context)
         * are excluded from the TSB miss handler, so it makes no sense
         * to have separate TSBs for primary, secondary and nucleus contexts.
         * Clearing the extension registers will ensure that the value of the
         * TSB Base register will be used as an address of TSB, making the code
         * compatible with the US port.
         *
         */
        itsb_primary_extension_write(0);
        itsb_nucleus_extension_write(0);
        dtsb_primary_extension_write(0);
        dtsb_secondary_extension_write(0);
        dtsb_nucleus_extension_write(0);
#endif
#endif
}

/** Perform sparc64-specific tasks when an address space is removed from the
 * processor.
 *
 * Demap TSBs.
 *
 * @param as Address space.
 */
void as_deinstall_arch(as_t *as)
{
        /*
         * Note that we don't and may not lock the address space. That's ok
         * since we only read members that are currently read-only.
         *
         * Moreover, the as->asid is protected by asidlock, which is being held.
         *
         */

#ifdef CONFIG_TSB
        uintptr_t base = ALIGN_DOWN(config.base, 1 << KERNEL_PAGE_WIDTH);

        assert(as->arch.itsb);
        assert(as->arch.dtsb);

        uintptr_t tsb = (uintptr_t) as->arch.itsb;

        if (!overlaps(tsb, TSB_SIZE, base, 1 << KERNEL_PAGE_WIDTH)) {
                /*
                 * TSBs were allocated from memory not covered
                 * by the locked 4M kernel DTLB entry. We need
                 * to demap the entry installed by as_install_arch().
                 */
                dtlb_demap(TLB_DEMAP_PAGE, TLB_DEMAP_NUCLEUS, tsb);
        }
#endif
}

/** @}
 */