rockbox/firmware/target/mips/mmu-mips.c
Aidan MacDonald 3ec66893e3 New port: FiiO M3K on bare metal
Change-Id: I7517e7d5459e129dcfc9465c6fbd708619888fbe
2021-03-28 00:01:37 +00:00

273 lines
8.4 KiB
C

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
*
* Copyright (C) 2009 by Maurus Cuelenaere
* Copyright (C) 2015 by Marcin Bukat
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#include "config.h"
#include "mips.h"
#include "mipsregs.h"
#include "system.h"
#include "mmu-mips.h"
#if CONFIG_CPU == JZ4732 || CONFIG_CPU == JZ4760B || CONFIG_CPU == X1000
/* XBurst core has 32 JTLB entries */
#define NR_TLB_ENTRIES 32
#else
#error please define NR_TLB_ENTRIES
#endif
#define BARRIER \
__asm__ __volatile__( \
" .set push \n" \
" .set noreorder \n" \
" ssnop \n" \
" ssnop \n" \
" ssnop \n" \
" ssnop \n" \
" ssnop \n" \
" ssnop \n" \
" .set pop \n");
#define DEFAULT_PAGE_SHIFT PL_4K
#define DEFAULT_PAGE_MASK PM_4K
#define UNIQUE_ENTRYHI(idx, ps) (A_K0BASE + ((idx) << (ps + 1)))
#define ASID_MASK M_EntryHiASID
#define VPN2_SHIFT S_EntryHiVPN2
#define PFN_SHIFT S_EntryLoPFN
#define PFN_MASK 0xffffff
static void local_flush_tlb_all(void)
{
unsigned long old_ctx;
int entry;
unsigned int old_irq = disable_irq_save();
/* Save old context and create impossible VPN2 value */
old_ctx = read_c0_entryhi();
write_c0_entrylo0(0);
write_c0_entrylo1(0);
BARRIER;
/* blast all entries except the wired one */
for(entry = read_c0_wired(); entry < NR_TLB_ENTRIES; entry++)
{
/* Make sure all entries differ and are in unmapped space, making them
* impossible to match */
write_c0_entryhi(UNIQUE_ENTRYHI(entry, DEFAULT_PAGE_SHIFT));
write_c0_index(entry);
BARRIER;
tlb_write_indexed();
}
BARRIER;
write_c0_entryhi(old_ctx);
restore_irq(old_irq);
}
static void add_wired_entry(unsigned long entrylo0, unsigned long entrylo1,
unsigned long entryhi, unsigned long pagemask)
{
unsigned long wired;
unsigned long old_pagemask;
unsigned long old_ctx;
unsigned int old_irq = disable_irq_save();
old_ctx = read_c0_entryhi() & ASID_MASK;
old_pagemask = read_c0_pagemask();
wired = read_c0_wired();
write_c0_wired(wired + 1);
write_c0_index(wired);
BARRIER;
write_c0_pagemask(pagemask);
write_c0_entryhi(entryhi);
write_c0_entrylo0(entrylo0);
write_c0_entrylo1(entrylo1);
BARRIER;
tlb_write_indexed();
BARRIER;
write_c0_entryhi(old_ctx);
BARRIER;
write_c0_pagemask(old_pagemask);
local_flush_tlb_all();
restore_irq(old_irq);
}
void map_address(unsigned long virtual, unsigned long physical,
unsigned long length, unsigned int cache_flags)
{
unsigned long entry0 = (physical & PFN_MASK) << PFN_SHIFT;
unsigned long entry1 = ((physical+length) & PFN_MASK) << PFN_SHIFT;
unsigned long entryhi = virtual & ~VPN2_SHIFT;
entry0 |= (M_EntryLoG | M_EntryLoV | (cache_flags << S_EntryLoC) );
entry1 |= (M_EntryLoG | M_EntryLoV | (cache_flags << S_EntryLoC) );
add_wired_entry(entry0, entry1, entryhi, DEFAULT_PAGE_MASK);
}
void mmu_init(void)
{
write_c0_pagemask(DEFAULT_PAGE_MASK);
write_c0_wired(0);
write_c0_framemask(0);
local_flush_tlb_all();
}
/* Target specific operations:
* - invalidate BTB (Branch Table Buffer)
* - sync barrier after cache operations */
#if CONFIG_CPU == JZ4732 || CONFIG_CPU == JZ4760B || CONFIG_CPU == X1000
#define INVALIDATE_BTB() \
do { \
register unsigned long tmp; \
__asm__ __volatile__( \
" .set push \n" \
" .set noreorder \n" \
" .set mips32 \n" \
" mfc0 %0, $16, 7 \n" \
" ssnop \n" \
" ori %0, 2 \n" \
" mtc0 %0, $16, 7 \n" \
" ssnop \n" \
" .set pop \n" \
: "=&r"(tmp)); \
} while (0)
#define SYNC_WB() __asm__ __volatile__ ("sync":::"memory")
#else /* !JZ4732 */
#define INVALIDATE_BTB() do { } while(0)
#define SYNC_WB() do { } while(0)
#endif /* CONFIG_CPU */
#define __CACHE_OP(op, addr) \
__asm__ __volatile__( \
" .set push\n\t \n" \
" .set noreorder \n" \
" .set mips32\n\t \n" \
" cache %0, %1 \n" \
" .set pop \n" \
: \
: "i" (op), "m"(*(unsigned char *)(addr)))
/* rockbox cache api */
/* Writeback whole D-cache
* Alias to commit_discard_dcache() as there is no index type
* variant of writeback-only operation
*/
void commit_dcache(void) __attribute__((alias("commit_discard_dcache")));
/* Writeback whole D-cache and invalidate D-cache lines */
void commit_discard_dcache(void)
{
register unsigned int i;
/* Use index type operation and iterate whole cache */
for (i=A_K0BASE; i<A_K0BASE+CACHE_SIZE; i+=CACHEALIGN_SIZE)
__CACHE_OP(DCIndexWBInv, i);
SYNC_WB();
}
/* Writeback lines of D-cache corresponding to address range and
* invalidate those D-cache lines
*/
void commit_discard_dcache_range(const void *base, unsigned int size)
{
char *ptr = CACHEALIGN_DOWN((char*)base);
char *end = CACHEALIGN_UP((char*)base + size);
for(; ptr != end; ptr += CACHEALIGN_SIZE)
__CACHE_OP(DCHitWBInv, ptr);
SYNC_WB();
}
/* Writeback lines of D-cache corresponding to address range
*/
void commit_dcache_range(const void *base, unsigned int size)
{
char *ptr = CACHEALIGN_DOWN((char*)base);
char *end = CACHEALIGN_UP((char*)base + size);
for(; ptr != end; ptr += CACHEALIGN_SIZE)
__CACHE_OP(DCHitWB, ptr);
SYNC_WB();
}
/* Invalidate D-cache lines corresponding to address range
* WITHOUT writeback
*/
void discard_dcache_range(const void *base, unsigned int size)
{
char *ptr = CACHEALIGN_DOWN((char*)base);
char *end = CACHEALIGN_UP((char*)base + size);
/* If the start of the buffer is unaligned, write
back that cacheline and shrink up the region
to discard. */
if (base != ptr) {
__CACHE_OP(DCHitWBInv, ptr);
ptr += CACHEALIGN_SIZE;
}
/* If the end of the buffer is unaligned, write back that
cacheline and shrink down the region to discard. */
if (ptr != end && (end !=((char*)base + size))) {
end -= CACHEALIGN_SIZE;
__CACHE_OP(DCHitWBInv, end);
}
/* Finally, discard whatever is left */
for(; ptr != end; ptr += CACHEALIGN_SIZE)
__CACHE_OP(DCHitInv, ptr);
SYNC_WB();
}
/* Invalidate whole I-cache */
static void discard_icache(void)
{
register unsigned int i;
asm volatile (".set push \n"
".set noreorder \n"
".set mips32 \n"
"mtc0 $0, $28 \n" /* TagLo */
"mtc0 $0, $29 \n" /* TagHi */
".set pop \n"
);
/* Use index type operation and iterate whole cache */
for (i=A_K0BASE; i<A_K0BASE+CACHE_SIZE; i+=CACHEALIGN_SIZE)
__CACHE_OP(ICIndexStTag, i);
INVALIDATE_BTB();
}
/* Invalidate the entire I-cache
* and writeback + invalidate the entire D-cache
*/
void commit_discard_idcache(void)
{
commit_discard_dcache();
discard_icache();
}