u-boot/arch/arm/cpu/armv8/cache_v8.c
York Sun cd4b0c5fea armv8: mmu: Add support of non-identical mapping
Introduce virtual and physical addresses in the mapping table. This change
have no impact on existing boards because they all use idential mapping.

Signed-off-by: York Sun <york.sun@nxp.com>
2016-07-15 09:01:43 -07:00

670 lines
15 KiB
C

/*
* (C) Copyright 2013
* David Feng <fenghua@phytium.com.cn>
*
* (C) Copyright 2016
* Alexander Graf <agraf@suse.de>
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <asm/system.h>
#include <asm/armv8/mmu.h>
DECLARE_GLOBAL_DATA_PTR;
#ifndef CONFIG_SYS_DCACHE_OFF
/*
* With 4k page granule, a virtual address is split into 4 lookup parts
* spanning 9 bits each:
*
* _______________________________________________
* | | | | | | |
* | 0 | Lv0 | Lv1 | Lv2 | Lv3 | off |
* |_______|_______|_______|_______|_______|_______|
* 63-48 47-39 38-30 29-21 20-12 11-00
*
* mask page size
*
* Lv0: FF8000000000 --
* Lv1: 7FC0000000 1G
* Lv2: 3FE00000 2M
* Lv3: 1FF000 4K
* off: FFF
*/
u64 get_tcr(int el, u64 *pips, u64 *pva_bits)
{
u64 max_addr = 0;
u64 ips, va_bits;
u64 tcr;
int i;
/* Find the largest address we need to support */
for (i = 0; mem_map[i].size || mem_map[i].attrs; i++)
max_addr = max(max_addr, mem_map[i].virt + mem_map[i].size);
/* Calculate the maximum physical (and thus virtual) address */
if (max_addr > (1ULL << 44)) {
ips = 5;
va_bits = 48;
} else if (max_addr > (1ULL << 42)) {
ips = 4;
va_bits = 44;
} else if (max_addr > (1ULL << 40)) {
ips = 3;
va_bits = 42;
} else if (max_addr > (1ULL << 36)) {
ips = 2;
va_bits = 40;
} else if (max_addr > (1ULL << 32)) {
ips = 1;
va_bits = 36;
} else {
ips = 0;
va_bits = 32;
}
if (el == 1) {
tcr = TCR_EL1_RSVD | (ips << 32) | TCR_EPD1_DISABLE;
} else if (el == 2) {
tcr = TCR_EL2_RSVD | (ips << 16);
} else {
tcr = TCR_EL3_RSVD | (ips << 16);
}
/* PTWs cacheable, inner/outer WBWA and inner shareable */
tcr |= TCR_TG0_4K | TCR_SHARED_INNER | TCR_ORGN_WBWA | TCR_IRGN_WBWA;
tcr |= TCR_T0SZ(va_bits);
if (pips)
*pips = ips;
if (pva_bits)
*pva_bits = va_bits;
return tcr;
}
#define MAX_PTE_ENTRIES 512
static int pte_type(u64 *pte)
{
return *pte & PTE_TYPE_MASK;
}
/* Returns the LSB number for a PTE on level <level> */
static int level2shift(int level)
{
/* Page is 12 bits wide, every level translates 9 bits */
return (12 + 9 * (3 - level));
}
static u64 *find_pte(u64 addr, int level)
{
int start_level = 0;
u64 *pte;
u64 idx;
u64 va_bits;
int i;
debug("addr=%llx level=%d\n", addr, level);
get_tcr(0, NULL, &va_bits);
if (va_bits < 39)
start_level = 1;
if (level < start_level)
return NULL;
/* Walk through all page table levels to find our PTE */
pte = (u64*)gd->arch.tlb_addr;
for (i = start_level; i < 4; i++) {
idx = (addr >> level2shift(i)) & 0x1FF;
pte += idx;
debug("idx=%llx PTE %p at level %d: %llx\n", idx, pte, i, *pte);
/* Found it */
if (i == level)
return pte;
/* PTE is no table (either invalid or block), can't traverse */
if (pte_type(pte) != PTE_TYPE_TABLE)
return NULL;
/* Off to the next level */
pte = (u64*)(*pte & 0x0000fffffffff000ULL);
}
/* Should never reach here */
return NULL;
}
/* Returns and creates a new full table (512 entries) */
static u64 *create_table(void)
{
u64 *new_table = (u64*)gd->arch.tlb_fillptr;
u64 pt_len = MAX_PTE_ENTRIES * sizeof(u64);
/* Allocate MAX_PTE_ENTRIES pte entries */
gd->arch.tlb_fillptr += pt_len;
if (gd->arch.tlb_fillptr - gd->arch.tlb_addr > gd->arch.tlb_size)
panic("Insufficient RAM for page table: 0x%lx > 0x%lx. "
"Please increase the size in get_page_table_size()",
gd->arch.tlb_fillptr - gd->arch.tlb_addr,
gd->arch.tlb_size);
/* Mark all entries as invalid */
memset(new_table, 0, pt_len);
return new_table;
}
static void set_pte_table(u64 *pte, u64 *table)
{
/* Point *pte to the new table */
debug("Setting %p to addr=%p\n", pte, table);
*pte = PTE_TYPE_TABLE | (ulong)table;
}
/* Splits a block PTE into table with subpages spanning the old block */
static void split_block(u64 *pte, int level)
{
u64 old_pte = *pte;
u64 *new_table;
u64 i = 0;
/* level describes the parent level, we need the child ones */
int levelshift = level2shift(level + 1);
if (pte_type(pte) != PTE_TYPE_BLOCK)
panic("PTE %p (%llx) is not a block. Some driver code wants to "
"modify dcache settings for an range not covered in "
"mem_map.", pte, old_pte);
new_table = create_table();
debug("Splitting pte %p (%llx) into %p\n", pte, old_pte, new_table);
for (i = 0; i < MAX_PTE_ENTRIES; i++) {
new_table[i] = old_pte | (i << levelshift);
/* Level 3 block PTEs have the table type */
if ((level + 1) == 3)
new_table[i] |= PTE_TYPE_TABLE;
debug("Setting new_table[%lld] = %llx\n", i, new_table[i]);
}
/* Set the new table into effect */
set_pte_table(pte, new_table);
}
/* Add one mm_region map entry to the page tables */
static void add_map(struct mm_region *map)
{
u64 *pte;
u64 virt = map->virt;
u64 phys = map->phys;
u64 size = map->size;
u64 attrs = map->attrs | PTE_TYPE_BLOCK | PTE_BLOCK_AF;
u64 blocksize;
int level;
u64 *new_table;
while (size) {
pte = find_pte(virt, 0);
if (pte && (pte_type(pte) == PTE_TYPE_FAULT)) {
debug("Creating table for virt 0x%llx\n", virt);
new_table = create_table();
set_pte_table(pte, new_table);
}
for (level = 1; level < 4; level++) {
pte = find_pte(virt, level);
if (!pte)
panic("pte not found\n");
blocksize = 1ULL << level2shift(level);
debug("Checking if pte fits for virt=%llx size=%llx blocksize=%llx\n",
virt, size, blocksize);
if (size >= blocksize && !(virt & (blocksize - 1))) {
/* Page fits, create block PTE */
debug("Setting PTE %p to block virt=%llx\n",
pte, virt);
*pte = phys | attrs;
virt += blocksize;
phys += blocksize;
size -= blocksize;
break;
} else if (pte_type(pte) == PTE_TYPE_FAULT) {
/* Page doesn't fit, create subpages */
debug("Creating subtable for virt 0x%llx blksize=%llx\n",
virt, blocksize);
new_table = create_table();
set_pte_table(pte, new_table);
} else if (pte_type(pte) == PTE_TYPE_BLOCK) {
debug("Split block into subtable for virt 0x%llx blksize=0x%llx\n",
virt, blocksize);
split_block(pte, level);
}
}
}
}
enum pte_type {
PTE_INVAL,
PTE_BLOCK,
PTE_LEVEL,
};
/*
* This is a recursively called function to count the number of
* page tables we need to cover a particular PTE range. If you
* call this with level = -1 you basically get the full 48 bit
* coverage.
*/
static int count_required_pts(u64 addr, int level, u64 maxaddr)
{
int levelshift = level2shift(level);
u64 levelsize = 1ULL << levelshift;
u64 levelmask = levelsize - 1;
u64 levelend = addr + levelsize;
int r = 0;
int i;
enum pte_type pte_type = PTE_INVAL;
for (i = 0; mem_map[i].size || mem_map[i].attrs; i++) {
struct mm_region *map = &mem_map[i];
u64 start = map->virt;
u64 end = start + map->size;
/* Check if the PTE would overlap with the map */
if (max(addr, start) <= min(levelend, end)) {
start = max(addr, start);
end = min(levelend, end);
/* We need a sub-pt for this level */
if ((start & levelmask) || (end & levelmask)) {
pte_type = PTE_LEVEL;
break;
}
/* Lv0 can not do block PTEs, so do levels here too */
if (level <= 0) {
pte_type = PTE_LEVEL;
break;
}
/* PTE is active, but fits into a block */
pte_type = PTE_BLOCK;
}
}
/*
* Block PTEs at this level are already covered by the parent page
* table, so we only need to count sub page tables.
*/
if (pte_type == PTE_LEVEL) {
int sublevel = level + 1;
u64 sublevelsize = 1ULL << level2shift(sublevel);
/* Account for the new sub page table ... */
r = 1;
/* ... and for all child page tables that one might have */
for (i = 0; i < MAX_PTE_ENTRIES; i++) {
r += count_required_pts(addr, sublevel, maxaddr);
addr += sublevelsize;
if (addr >= maxaddr) {
/*
* We reached the end of address space, no need
* to look any further.
*/
break;
}
}
}
return r;
}
/* Returns the estimated required size of all page tables */
__weak u64 get_page_table_size(void)
{
u64 one_pt = MAX_PTE_ENTRIES * sizeof(u64);
u64 size = 0;
u64 va_bits;
int start_level = 0;
get_tcr(0, NULL, &va_bits);
if (va_bits < 39)
start_level = 1;
/* Account for all page tables we would need to cover our memory map */
size = one_pt * count_required_pts(0, start_level - 1, 1ULL << va_bits);
/*
* We need to duplicate our page table once to have an emergency pt to
* resort to when splitting page tables later on
*/
size *= 2;
/*
* We may need to split page tables later on if dcache settings change,
* so reserve up to 4 (random pick) page tables for that.
*/
size += one_pt * 4;
return size;
}
void setup_pgtables(void)
{
int i;
if (!gd->arch.tlb_fillptr || !gd->arch.tlb_addr)
panic("Page table pointer not setup.");
/*
* Allocate the first level we're on with invalidate entries.
* If the starting level is 0 (va_bits >= 39), then this is our
* Lv0 page table, otherwise it's the entry Lv1 page table.
*/
create_table();
/* Now add all MMU table entries one after another to the table */
for (i = 0; mem_map[i].size || mem_map[i].attrs; i++)
add_map(&mem_map[i]);
}
static void setup_all_pgtables(void)
{
u64 tlb_addr = gd->arch.tlb_addr;
/* Reset the fill ptr */
gd->arch.tlb_fillptr = tlb_addr;
/* Create normal system page tables */
setup_pgtables();
/* Create emergency page tables */
gd->arch.tlb_addr = gd->arch.tlb_fillptr;
setup_pgtables();
gd->arch.tlb_emerg = gd->arch.tlb_addr;
gd->arch.tlb_addr = tlb_addr;
}
/* to activate the MMU we need to set up virtual memory */
__weak void mmu_setup(void)
{
int el;
/* Set up page tables only once */
if (!gd->arch.tlb_fillptr)
setup_all_pgtables();
el = current_el();
set_ttbr_tcr_mair(el, gd->arch.tlb_addr, get_tcr(el, NULL, NULL),
MEMORY_ATTRIBUTES);
/* enable the mmu */
set_sctlr(get_sctlr() | CR_M);
}
/*
* Performs a invalidation of the entire data cache at all levels
*/
void invalidate_dcache_all(void)
{
__asm_invalidate_dcache_all();
}
/*
* Performs a clean & invalidation of the entire data cache at all levels.
* This function needs to be inline to avoid using stack.
* __asm_flush_l3_cache return status of timeout
*/
inline void flush_dcache_all(void)
{
int ret;
__asm_flush_dcache_all();
ret = __asm_flush_l3_cache();
if (ret)
debug("flushing dcache returns 0x%x\n", ret);
else
debug("flushing dcache successfully.\n");
}
/*
* Invalidates range in all levels of D-cache/unified cache
*/
void invalidate_dcache_range(unsigned long start, unsigned long stop)
{
__asm_flush_dcache_range(start, stop);
}
/*
* Flush range(clean & invalidate) from all levels of D-cache/unified cache
*/
void flush_dcache_range(unsigned long start, unsigned long stop)
{
__asm_flush_dcache_range(start, stop);
}
void dcache_enable(void)
{
/* The data cache is not active unless the mmu is enabled */
if (!(get_sctlr() & CR_M)) {
invalidate_dcache_all();
__asm_invalidate_tlb_all();
mmu_setup();
}
set_sctlr(get_sctlr() | CR_C);
}
void dcache_disable(void)
{
uint32_t sctlr;
sctlr = get_sctlr();
/* if cache isn't enabled no need to disable */
if (!(sctlr & CR_C))
return;
set_sctlr(sctlr & ~(CR_C|CR_M));
flush_dcache_all();
__asm_invalidate_tlb_all();
}
int dcache_status(void)
{
return (get_sctlr() & CR_C) != 0;
}
u64 *__weak arch_get_page_table(void) {
puts("No page table offset defined\n");
return NULL;
}
static bool is_aligned(u64 addr, u64 size, u64 align)
{
return !(addr & (align - 1)) && !(size & (align - 1));
}
static u64 set_one_region(u64 start, u64 size, u64 attrs, int level)
{
int levelshift = level2shift(level);
u64 levelsize = 1ULL << levelshift;
u64 *pte = find_pte(start, level);
/* Can we can just modify the current level block PTE? */
if (is_aligned(start, size, levelsize)) {
*pte &= ~PMD_ATTRINDX_MASK;
*pte |= attrs;
debug("Set attrs=%llx pte=%p level=%d\n", attrs, pte, level);
return levelsize;
}
/* Unaligned or doesn't fit, maybe split block into table */
debug("addr=%llx level=%d pte=%p (%llx)\n", start, level, pte, *pte);
/* Maybe we need to split the block into a table */
if (pte_type(pte) == PTE_TYPE_BLOCK)
split_block(pte, level);
/* And then double-check it became a table or already is one */
if (pte_type(pte) != PTE_TYPE_TABLE)
panic("PTE %p (%llx) for addr=%llx should be a table",
pte, *pte, start);
/* Roll on to the next page table level */
return 0;
}
void mmu_set_region_dcache_behaviour(phys_addr_t start, size_t size,
enum dcache_option option)
{
u64 attrs = PMD_ATTRINDX(option);
u64 real_start = start;
u64 real_size = size;
debug("start=%lx size=%lx\n", (ulong)start, (ulong)size);
if (!gd->arch.tlb_emerg)
panic("Emergency page table not setup.");
/*
* We can not modify page tables that we're currently running on,
* so we first need to switch to the "emergency" page tables where
* we can safely modify our primary page tables and then switch back
*/
__asm_switch_ttbr(gd->arch.tlb_emerg);
/*
* Loop through the address range until we find a page granule that fits
* our alignment constraints, then set it to the new cache attributes
*/
while (size > 0) {
int level;
u64 r;
for (level = 1; level < 4; level++) {
r = set_one_region(start, size, attrs, level);
if (r) {
/* PTE successfully replaced */
size -= r;
start += r;
break;
}
}
}
/* We're done modifying page tables, switch back to our primary ones */
__asm_switch_ttbr(gd->arch.tlb_addr);
/*
* Make sure there's nothing stale in dcache for a region that might
* have caches off now
*/
flush_dcache_range(real_start, real_start + real_size);
}
#else /* CONFIG_SYS_DCACHE_OFF */
/*
* For SPL builds, we may want to not have dcache enabled. Any real U-Boot
* running however really wants to have dcache and the MMU active. Check that
* everything is sane and give the developer a hint if it isn't.
*/
#ifndef CONFIG_SPL_BUILD
#error Please describe your MMU layout in CONFIG_SYS_MEM_MAP and enable dcache.
#endif
void invalidate_dcache_all(void)
{
}
void flush_dcache_all(void)
{
}
void dcache_enable(void)
{
}
void dcache_disable(void)
{
}
int dcache_status(void)
{
return 0;
}
void mmu_set_region_dcache_behaviour(phys_addr_t start, size_t size,
enum dcache_option option)
{
}
#endif /* CONFIG_SYS_DCACHE_OFF */
#ifndef CONFIG_SYS_ICACHE_OFF
void icache_enable(void)
{
__asm_invalidate_icache_all();
set_sctlr(get_sctlr() | CR_I);
}
void icache_disable(void)
{
set_sctlr(get_sctlr() & ~CR_I);
}
int icache_status(void)
{
return (get_sctlr() & CR_I) != 0;
}
void invalidate_icache_all(void)
{
__asm_invalidate_icache_all();
}
#else /* CONFIG_SYS_ICACHE_OFF */
void icache_enable(void)
{
}
void icache_disable(void)
{
}
int icache_status(void)
{
return 0;
}
void invalidate_icache_all(void)
{
}
#endif /* CONFIG_SYS_ICACHE_OFF */
/*
* Enable dCache & iCache, whether cache is actually enabled
* depend on CONFIG_SYS_DCACHE_OFF and CONFIG_SYS_ICACHE_OFF
*/
void __weak enable_caches(void)
{
icache_enable();
dcache_enable();
}