/*
* Copyright (C) 2005 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.
*/
#include <arch/mm/tlb.h>
#include <mm/tlb.h>
#include <genarch/mm/asid_fifo.h>
#include <arch/mm/frame.h>
#include <arch/mm/page.h>
#include <arch/mm/mmu.h>
#include <print.h>
#include <arch/types.h>
#include <typedefs.h>
#include <config.h>
#include <arch/trap/trap.h>
/** Initialize ITLB and DTLB.
*
* The goal of this function is to disable MMU
* so that both TLBs can be purged and new
* kernel 4M locked entry can be installed.
* After TLB is initialized, MMU is enabled
* again.
*
* Switching MMU off imposes the requirement for
* the kernel to run in identity mapped environment.
*/
void tlb_arch_init(void)
{
tlb_tag_access_reg_t tag;
tlb_data_t data;
frame_address_t fr;
page_address_t pg;
asid_fifo_init();
fr.address = config.base;
pg.address = config.base;
immu_disable();
dmmu_disable();
/*
* For simplicity, we do identity mapping of first 4M of memory.
* The very next change should be leaving the first 4M unmapped.
*/
tag.value = 0;
tag.vpn = pg.vpn;
itlb_tag_access_write(tag.value);
dtlb_tag_access_write(tag.value);
data.value = 0;
data.v = true;
data.size = PAGESIZE_4M;
data.pfn = fr.pfn;
data.l = true;
data.cp = 1;
data.cv = 1;
data.p = true;
data.w = true;
data.g = true;
itlb_data_in_write(data.value);
dtlb_data_in_write(data.value);
/*
* Register window traps can occur before MMU is enabled again.
* This ensures that any such traps will be handled from
* kernel identity mapped trap handler.
*/
trap_switch_trap_table();
tlb_invalidate_all();
dmmu_enable();
immu_enable();
}
/** Print contents of both TLBs. */
void tlb_print(void)
{
int i;
tlb_data_t d;
tlb_tag_read_reg_t t;
for (i = 0; i < ITLB_ENTRY_COUNT; i++) {
d.value = itlb_data_access_read(i);
t.value = itlb_tag_read_read(i);
printf("%d: vpn=%Q, context=%d, v=%d, size=%d, nfo=%d, ie=%d, soft2=%X, diag=%X, pfn=%X, soft=%X, l=%d, cp=%d, cv=%d, e=%d, p=%d, w=%d, g=%d\n", i, t.vpn, t.context, d.v, d.size, d.nfo, d.ie, d.soft2, d.diag, d.pfn, d.soft, d.l, d.cp, d.cv, d.e, d.p, d.w, d.g);
}
for (i = 0; i < DTLB_ENTRY_COUNT; i++) {
d.value = dtlb_data_access_read(i);
t.value = dtlb_tag_read_read(i);
printf("%d: vpn=%Q, context=%d, v=%d, size=%d, nfo=%d, ie=%d, soft2=%X, diag=%X, pfn=%X, soft=%X, l=%d, cp=%d, cv=%d, e=%d, p=%d, w=%d, g=%d\n", i, t.vpn, t.context, d.v, d.size, d.nfo, d.ie, d.soft2, d.diag, d.pfn, d.soft, d.l, d.cp, d.cv, d.e, d.p, d.w, d.g);
}
}
/** Invalidate all unlocked ITLB and DTLB entries. */
void tlb_invalidate_all(void)
{
int i;
tlb_data_t d;
tlb_tag_read_reg_t t;
for (i = 0; i < ITLB_ENTRY_COUNT; i++) {
d.value = itlb_data_access_read(i);
if (!d.l) {
t.value = itlb_tag_read_read(i);
d.v = false;
itlb_tag_access_write(t.value);
itlb_data_access_write(i, d.value);
}
}
for (i = 0; i < DTLB_ENTRY_COUNT; i++) {
d.value = dtlb_data_access_read(i);
if (!d.l) {
t.value = dtlb_tag_read_read(i);
d.v = false;
dtlb_tag_access_write(t.value);
dtlb_data_access_write(i, d.value);
}
}
}
/** Invalidate all ITLB and DTLB entries that belong to specified ASID (Context).
*
* @param asid Address Space ID.
*/
void tlb_invalidate_asid(asid_t asid)
{
/* TODO: write asid to some Context register and encode the register in second parameter below. */
itlb_demap(TLB_DEMAP_CONTEXT, TLB_DEMAP_NUCLEUS, 0);
dtlb_demap(TLB_DEMAP_CONTEXT, TLB_DEMAP_NUCLEUS, 0);
}
/** Invalidate all ITLB and DTLB entries for specified page range in specified address space.
*
* @param asid Address Space ID.
* @param page First page which to sweep out from ITLB and DTLB.
* @param cnt Number of ITLB and DTLB entries to invalidate.
*/
void tlb_invalidate_pages(asid_t asid, __address page, count_t cnt)
{
int i;
for (i = 0; i < cnt; i++) {
/* TODO: write asid to some Context register and encode the register in second parameter below. */
itlb_demap(TLB_DEMAP_PAGE, TLB_DEMAP_NUCLEUS, page + i * PAGE_SIZE);
dtlb_demap(TLB_DEMAP_PAGE, TLB_DEMAP_NUCLEUS, page + i * PAGE_SIZE);
}
}