stm32mp: don't map the reserved region with no-map property

No more map the reserved region with "no-map" property by marking
the corresponding TLB entries with invalid entry (=0) to avoid
speculative access.

The device tree parsing done in lmb_init_and_reserve() takes a
long time when it is executed without data cache, so it is called in
enable_caches() before to disable it.

This patch fixes an issue where predictive read access on secure DDR
OP-TEE reserved area are caught by firewall.

  Series-cc: marex
  Series-cc: pch
  Series-cc: marek.bykowski@gmail.com
  Series-cc: Ard Biesheuvel <ardb@kernel.org>
  Series-cc: Etienne Carriere <etienne.carriere@linaro.org>

Signed-off-by: Patrick Delaunay <patrick.delaunay@foss.st.com>
This commit is contained in:
Patrick Delaunay 2021-05-07 14:50:35 +02:00 committed by Tom Rini
parent 7dc6068fc1
commit ade4e0428f

View file

@ -12,6 +12,7 @@
#include <env.h>
#include <init.h>
#include <log.h>
#include <lmb.h>
#include <misc.h>
#include <net.h>
#include <asm/io.h>
@ -90,6 +91,8 @@
*/
u8 early_tlb[PGTABLE_SIZE] __section(".data") __aligned(0x4000);
struct lmb lmb;
#if !defined(CONFIG_SPL) || defined(CONFIG_SPL_BUILD)
#ifndef CONFIG_TFABOOT
static void security_init(void)
@ -221,6 +224,8 @@ void dram_bank_mmu_setup(int bank)
int i;
phys_addr_t start;
phys_size_t size;
bool use_lmb = false;
enum dcache_option option;
if (IS_ENABLED(CONFIG_SPL_BUILD)) {
start = ALIGN_DOWN(STM32_SYSRAM_BASE, MMU_SECTION_SIZE);
@ -229,6 +234,7 @@ void dram_bank_mmu_setup(int bank)
/* bd->bi_dram is available only after relocation */
start = bd->bi_dram[bank].start;
size = bd->bi_dram[bank].size;
use_lmb = true;
} else {
/* mark cacheable and executable the beggining of the DDR */
start = STM32_DDR_BASE;
@ -237,8 +243,12 @@ void dram_bank_mmu_setup(int bank)
for (i = start >> MMU_SECTION_SHIFT;
i < (start >> MMU_SECTION_SHIFT) + (size >> MMU_SECTION_SHIFT);
i++)
set_section_dcache(i, DCACHE_DEFAULT_OPTION);
i++) {
option = DCACHE_DEFAULT_OPTION;
if (use_lmb && lmb_is_reserved_flags(&lmb, i << MMU_SECTION_SHIFT, LMB_NOMAP))
option = 0; /* INVALID ENTRY in TLB */
set_section_dcache(i, option);
}
}
/*
* initialize the MMU and activate cache in SPL or in U-Boot pre-reloc stage
@ -302,6 +312,9 @@ int arch_cpu_init(void)
void enable_caches(void)
{
/* parse device tree when data cache is still activated */
lmb_init_and_reserve(&lmb, gd->bd, (void *)gd->fdt_blob);
/* I-cache is already enabled in start.S: icache_enable() not needed */
/* deactivate the data cache, early enabled in arch_cpu_init() */