u-boot/arch/arm/lib/cache-cp15.c
Marek Szyprowski d877f8fd0f arm: provide a function for boards init code to modify MMU virtual-physical map
Provide function for setting arbitrary virtual-physical MMU mapping
and cache settings for the given region.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
2020-07-10 14:10:43 -04:00

331 lines
7.4 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* (C) Copyright 2002
* Wolfgang Denk, DENX Software Engineering, wd@denx.de.
*/
#include <common.h>
#include <cpu_func.h>
#include <log.h>
#include <asm/system.h>
#include <asm/cache.h>
#include <linux/compiler.h>
#include <asm/armv7_mpu.h>
#if !(CONFIG_IS_ENABLED(SYS_ICACHE_OFF) && CONFIG_IS_ENABLED(SYS_DCACHE_OFF))
DECLARE_GLOBAL_DATA_PTR;
#ifdef CONFIG_SYS_ARM_MMU
__weak void arm_init_before_mmu(void)
{
}
__weak void arm_init_domains(void)
{
}
static void set_section_phys(int section, phys_addr_t phys,
enum dcache_option option)
{
#ifdef CONFIG_ARMV7_LPAE
u64 *page_table = (u64 *)gd->arch.tlb_addr;
/* Need to set the access flag to not fault */
u64 value = TTB_SECT_AP | TTB_SECT_AF;
#else
u32 *page_table = (u32 *)gd->arch.tlb_addr;
u32 value = TTB_SECT_AP;
#endif
/* Add the page offset */
value |= phys;
/* Add caching bits */
value |= option;
/* Set PTE */
page_table[section] = value;
}
void set_section_dcache(int section, enum dcache_option option)
{
set_section_phys(section, (u32)section << MMU_SECTION_SHIFT, option);
}
__weak void mmu_page_table_flush(unsigned long start, unsigned long stop)
{
debug("%s: Warning: not implemented\n", __func__);
}
void mmu_set_region_dcache_behaviour_phys(phys_addr_t start, phys_addr_t phys,
size_t size, enum dcache_option option)
{
#ifdef CONFIG_ARMV7_LPAE
u64 *page_table = (u64 *)gd->arch.tlb_addr;
#else
u32 *page_table = (u32 *)gd->arch.tlb_addr;
#endif
unsigned long startpt, stoppt;
unsigned long upto, end;
/* div by 2 before start + size to avoid phys_addr_t overflow */
end = ALIGN((start / 2) + (size / 2), MMU_SECTION_SIZE / 2)
>> (MMU_SECTION_SHIFT - 1);
start = start >> MMU_SECTION_SHIFT;
#ifdef CONFIG_ARMV7_LPAE
debug("%s: start=%pa, size=%zu, option=%llx\n", __func__, &start, size,
option);
#else
debug("%s: start=%pa, size=%zu, option=0x%x\n", __func__, &start, size,
option);
#endif
for (upto = start; upto < end; upto++, phys += MMU_SECTION_SIZE)
set_section_phys(upto, phys, option);
/*
* Make sure range is cache line aligned
* Only CPU maintains page tables, hence it is safe to always
* flush complete cache lines...
*/
startpt = (unsigned long)&page_table[start];
startpt &= ~(CONFIG_SYS_CACHELINE_SIZE - 1);
stoppt = (unsigned long)&page_table[end];
stoppt = ALIGN(stoppt, CONFIG_SYS_CACHELINE_SIZE);
mmu_page_table_flush(startpt, stoppt);
}
void mmu_set_region_dcache_behaviour(phys_addr_t start, size_t size,
enum dcache_option option)
{
mmu_set_region_dcache_behaviour_phys(start, start, size, option);
}
__weak void dram_bank_mmu_setup(int bank)
{
bd_t *bd = gd->bd;
int i;
/* bd->bi_dram is available only after relocation */
if ((gd->flags & GD_FLG_RELOC) == 0)
return;
debug("%s: bank: %d\n", __func__, bank);
for (i = bd->bi_dram[bank].start >> MMU_SECTION_SHIFT;
i < (bd->bi_dram[bank].start >> MMU_SECTION_SHIFT) +
(bd->bi_dram[bank].size >> MMU_SECTION_SHIFT);
i++)
set_section_dcache(i, DCACHE_DEFAULT_OPTION);
}
/* to activate the MMU we need to set up virtual memory: use 1M areas */
static inline void mmu_setup(void)
{
int i;
u32 reg;
arm_init_before_mmu();
/* Set up an identity-mapping for all 4GB, rw for everyone */
for (i = 0; i < ((4096ULL * 1024 * 1024) >> MMU_SECTION_SHIFT); i++)
set_section_dcache(i, DCACHE_OFF);
for (i = 0; i < CONFIG_NR_DRAM_BANKS; i++) {
dram_bank_mmu_setup(i);
}
#if defined(CONFIG_ARMV7_LPAE) && __LINUX_ARM_ARCH__ != 4
/* Set up 4 PTE entries pointing to our 4 1GB page tables */
for (i = 0; i < 4; i++) {
u64 *page_table = (u64 *)(gd->arch.tlb_addr + (4096 * 4));
u64 tpt = gd->arch.tlb_addr + (4096 * i);
page_table[i] = tpt | TTB_PAGETABLE;
}
reg = TTBCR_EAE;
#if defined(CONFIG_SYS_ARM_CACHE_WRITETHROUGH)
reg |= TTBCR_ORGN0_WT | TTBCR_IRGN0_WT;
#elif defined(CONFIG_SYS_ARM_CACHE_WRITEALLOC)
reg |= TTBCR_ORGN0_WBWA | TTBCR_IRGN0_WBWA;
#else
reg |= TTBCR_ORGN0_WBNWA | TTBCR_IRGN0_WBNWA;
#endif
if (is_hyp()) {
/* Set HTCR to enable LPAE */
asm volatile("mcr p15, 4, %0, c2, c0, 2"
: : "r" (reg) : "memory");
/* Set HTTBR0 */
asm volatile("mcrr p15, 4, %0, %1, c2"
:
: "r"(gd->arch.tlb_addr + (4096 * 4)), "r"(0)
: "memory");
/* Set HMAIR */
asm volatile("mcr p15, 4, %0, c10, c2, 0"
: : "r" (MEMORY_ATTRIBUTES) : "memory");
} else {
/* Set TTBCR to enable LPAE */
asm volatile("mcr p15, 0, %0, c2, c0, 2"
: : "r" (reg) : "memory");
/* Set 64-bit TTBR0 */
asm volatile("mcrr p15, 0, %0, %1, c2"
:
: "r"(gd->arch.tlb_addr + (4096 * 4)), "r"(0)
: "memory");
/* Set MAIR */
asm volatile("mcr p15, 0, %0, c10, c2, 0"
: : "r" (MEMORY_ATTRIBUTES) : "memory");
}
#elif defined(CONFIG_CPU_V7A)
if (is_hyp()) {
/* Set HTCR to disable LPAE */
asm volatile("mcr p15, 4, %0, c2, c0, 2"
: : "r" (0) : "memory");
} else {
/* Set TTBCR to disable LPAE */
asm volatile("mcr p15, 0, %0, c2, c0, 2"
: : "r" (0) : "memory");
}
/* Set TTBR0 */
reg = gd->arch.tlb_addr & TTBR0_BASE_ADDR_MASK;
#if defined(CONFIG_SYS_ARM_CACHE_WRITETHROUGH)
reg |= TTBR0_RGN_WT | TTBR0_IRGN_WT;
#elif defined(CONFIG_SYS_ARM_CACHE_WRITEALLOC)
reg |= TTBR0_RGN_WBWA | TTBR0_IRGN_WBWA;
#else
reg |= TTBR0_RGN_WB | TTBR0_IRGN_WB;
#endif
asm volatile("mcr p15, 0, %0, c2, c0, 0"
: : "r" (reg) : "memory");
#else
/* Copy the page table address to cp15 */
asm volatile("mcr p15, 0, %0, c2, c0, 0"
: : "r" (gd->arch.tlb_addr) : "memory");
#endif
/* Set the access control to all-supervisor */
asm volatile("mcr p15, 0, %0, c3, c0, 0"
: : "r" (~0));
arm_init_domains();
/* and enable the mmu */
reg = get_cr(); /* get control reg. */
set_cr(reg | CR_M);
}
static int mmu_enabled(void)
{
return get_cr() & CR_M;
}
#endif /* CONFIG_SYS_ARM_MMU */
/* cache_bit must be either CR_I or CR_C */
static void cache_enable(uint32_t cache_bit)
{
uint32_t reg;
/* The data cache is not active unless the mmu/mpu is enabled too */
#ifdef CONFIG_SYS_ARM_MMU
if ((cache_bit == CR_C) && !mmu_enabled())
mmu_setup();
#elif defined(CONFIG_SYS_ARM_MPU)
if ((cache_bit == CR_C) && !mpu_enabled()) {
printf("Consider enabling MPU before enabling caches\n");
return;
}
#endif
reg = get_cr(); /* get control reg. */
set_cr(reg | cache_bit);
}
/* cache_bit must be either CR_I or CR_C */
static void cache_disable(uint32_t cache_bit)
{
uint32_t reg;
reg = get_cr();
if (cache_bit == CR_C) {
/* if cache isn;t enabled no need to disable */
if ((reg & CR_C) != CR_C)
return;
#ifdef CONFIG_SYS_ARM_MMU
/* if disabling data cache, disable mmu too */
cache_bit |= CR_M;
#endif
}
reg = get_cr();
#ifdef CONFIG_SYS_ARM_MMU
if (cache_bit == (CR_C | CR_M))
#elif defined(CONFIG_SYS_ARM_MPU)
if (cache_bit == CR_C)
#endif
flush_dcache_all();
set_cr(reg & ~cache_bit);
}
#endif
#if CONFIG_IS_ENABLED(SYS_ICACHE_OFF)
void icache_enable(void)
{
return;
}
void icache_disable(void)
{
return;
}
int icache_status(void)
{
return 0; /* always off */
}
#else
void icache_enable(void)
{
cache_enable(CR_I);
}
void icache_disable(void)
{
cache_disable(CR_I);
}
int icache_status(void)
{
return (get_cr() & CR_I) != 0;
}
#endif
#if CONFIG_IS_ENABLED(SYS_DCACHE_OFF)
void dcache_enable(void)
{
return;
}
void dcache_disable(void)
{
return;
}
int dcache_status(void)
{
return 0; /* always off */
}
#else
void dcache_enable(void)
{
cache_enable(CR_C);
}
void dcache_disable(void)
{
cache_disable(CR_C);
}
int dcache_status(void)
{
return (get_cr() & CR_C) != 0;
}
#endif