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/*
* This file is part of the coreboot project.
*
* Copyright 2013 Google Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. 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.
* 3. 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 AND CONTRIBUTORS ``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 OR CONTRIBUTORS 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.
*
* cache.c: Cache maintenance routines for ARMv7-A and ARMv7-R
*
* Reference: ARM Architecture Reference Manual, ARMv7-A and ARMv7-R edition
*/
#include <types.h>
#include <arch/cache.h>
#define bitmask(high, low) ((1UL << (high)) + \
((1UL << (high)) - 1) - ((1UL << (low)) - 1))
/* Basic log2() implementation. Note: log2(0) is 0 for our purposes. */
/* FIXME: src/include/lib.h is difficult to work with due to romcc */
static unsigned long log2(unsigned long u)
{
int i = 0;
while (u >>= 1)
i++;
return i;
}
void tlb_invalidate_all(void)
{
/*
* FIXME: ARMv7 Architecture Ref. Manual claims that the distinction
* instruction vs. data TLBs is deprecated in ARMv7, however this does
* not seem to be the case as of Cortex-A15.
*/
tlbiall();
dtlbiall();
itlbiall();
isb();
dsb();
}
void icache_invalidate_all(void)
{
/*
* icache can be entirely invalidated with one operation.
* Note: If branch predictors are architecturally-visible, ICIALLU
* also performs a BPIALL operation (B2-1283 in arch manual)
*/
iciallu();
isb();
}
enum dcache_op {
OP_DCCISW,
OP_DCISW,
OP_DCCIMVAC,
OP_DCCMVAC,
};
/*
* Do a dcache operation on entire cache by set/way. This is done for
* portability because mapping of memory address to cache location is
* implementation defined (See note on "Requirements for operations by
* set/way" in arch ref. manual).
*/
static void dcache_op_set_way(enum dcache_op op)
{
uint32_t ccsidr;
unsigned int associativity, num_sets, linesize_bytes;
unsigned int set, way;
unsigned int level;
level = (read_csselr() >> 1) & 0x7;
/*
* dcache must be invalidated by set/way for portability since virtual
* memory mapping is system-defined. The number of sets and
* associativity is given by CCSIDR. We'll use DCISW to invalidate the
* dcache.
*/
ccsidr = read_ccsidr();
/* FIXME: rounding up required here? */
num_sets = ((ccsidr & bitmask(27, 13)) >> 13) + 1;
associativity = ((ccsidr & bitmask(12, 3)) >> 3) + 1;
/* FIXME: do we need to use CTR.DminLine here? */
linesize_bytes = (1 << ((ccsidr & 0x7) + 2)) * 4;
/*
* Set/way operations require an interesting bit packing. See section
* B4-35 in the ARMv7 Architecture Reference Manual:
*
* A: Log2(associativity)
* B: L+S
* L: Log2(linesize)
* S: Log2(num_sets)
*
* The bits are packed as follows:
* 31 31-A B B-1 L L-1 4 3 1 0
* |---|-------------|--------|-------|-----|-|
* |Way| zeros | Set | zeros |level|0|
* |---|-------------|--------|-------|-----|-|
*/
for (way = 0; way < associativity; way++) {
for (set = 0; set < num_sets; set++) {
uint32_t val = 0;
val |= way << (32 - log2(associativity));
val |= set << log2(linesize_bytes);
val |= level << 1;
switch(op) {
case OP_DCCISW:
dccisw(val);
break;
case OP_DCISW:
dcisw(val);
break;
default:
break;
}
}
}
dsb();
}
void dcache_clean_invalidate_all(void)
{
dcache_op_set_way(OP_DCCISW);
}
void dcache_invalidate_all(void)
{
dcache_op_set_way(OP_DCISW);
}
static unsigned int line_bytes(void)
{
uint32_t ccsidr;
unsigned int size;
ccsidr = read_ccsidr();
/* [2:0] - Indicates (Log2(number of words in cache line)) - 2 */
size = 1 << ((ccsidr & 0x7) + 2); /* words per line */
size *= sizeof(unsigned int); /* bytes per line */
return size;
}
/*
* Do a dcache operation by modified virtual address. This is useful for
* maintaining coherency in drivers which do DMA transfers and only need to
* perform cache maintenance on a particular memory range rather than the
* entire cache.
*/
static void dcache_op_mva(unsigned long addr,
unsigned long len, enum dcache_op op)
{
unsigned long line, linesize;
linesize = line_bytes();
line = addr & ~(linesize - 1);
dsb();
while (line < addr + len) {
switch(op) {
case OP_DCCIMVAC:
dccimvac(line);
break;
default:
break;
}
line += linesize;
}
isb();
}
void dcache_clean_by_mva(unsigned long addr, unsigned long len)
{
dcache_op_mva(addr, len, OP_DCCMVAC);
}
void dcache_clean_invalidate_by_mva(unsigned long addr, unsigned long len)
{
dcache_op_mva(addr, len, OP_DCCIMVAC);
}
void dcache_mmu_disable(void)
{
uint32_t sctlr;
sctlr = read_sctlr();
dcache_clean_invalidate_all();
sctlr &= ~(SCTLR_C | SCTLR_M);
write_sctlr(sctlr);
}
void dcache_mmu_enable(void)
{
uint32_t sctlr;
sctlr = read_sctlr();
dcache_clean_invalidate_all();
sctlr |= SCTLR_C | SCTLR_M;
write_sctlr(sctlr);
}
void armv7_invalidate_caches(void)
{
uint32_t clidr;
int level;
/* Invalidate branch predictor */
bpiall();
/* Iterate thru each cache identified in CLIDR and invalidate */
clidr = read_clidr();
for (level = 0; level < 7; level++) {
unsigned int ctype = (clidr >> (level * 3)) & 0x7;
uint32_t csselr;
switch(ctype) {
case 0x0:
/* no cache */
break;
case 0x1:
/* icache only */
csselr = (level << 1) | 1;
write_csselr(csselr);
icache_invalidate_all();
break;
case 0x2:
case 0x4:
/* dcache only or unified cache */
dcache_invalidate_all();
break;
case 0x3:
/* separate icache and dcache */
csselr = (level << 1) | 1;
write_csselr(csselr);
icache_invalidate_all();
csselr = level << 1;
write_csselr(csselr);
dcache_invalidate_all();
break;
default:
/* reserved */
break;
}
}
/* Invalidate TLB */
tlb_invalidate_all();
}
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