imx8m: Fix MMU table issue for OPTEE memory

When running with OPTEE, the MMU table in u-boot does not remove the OPTEE
memory from its settings. So ARM speculative prefetch in u-boot may access
that OPTEE memory. Due to trust zone is enabled by OPTEE and that memory
is set to secure access, then the speculative prefetch will fail and cause
various memory issue in u-boot.
The fail address register and int_status register in trustzone has logged
that speculative access from u-boot.

Signed-off-by: Peng Fan <peng.fan@nxp.com>

diff --git a/arch/arm/mach-imx/imx8m/soc.c b/arch/arm/mach-imx/imx8m/soc.c
index 5115471..dd393b5 100644 (file)
--- a/arch/arm/mach-imx/imx8m/soc.c
+++ b/arch/arm/mach-imx/imx8m/soc.c
@@ -112,16 +112,18 @@ static struct mm_region imx8m_mem_map[] = {
                /* DRAM1 */
                .virt = 0x40000000UL,
                .phys = 0x40000000UL,
-               .size = 0xC0000000UL,
+               .size = PHYS_SDRAM_SIZE,
                .attrs = PTE_BLOCK_MEMTYPE(MT_NORMAL) |
                         PTE_BLOCK_OUTER_SHARE
+#ifdef PHYS_SDRAM_2_SIZE
        }, {
                /* DRAM2 */
                .virt = 0x100000000UL,
                .phys = 0x100000000UL,
-               .size = 0x040000000UL,
+               .size = PHYS_SDRAM_2_SIZE,
                .attrs = PTE_BLOCK_MEMTYPE(MT_NORMAL) |
                         PTE_BLOCK_OUTER_SHARE
+#endif
        }, {
                /* List terminator */
                0,
@@ -130,6 +132,20 @@ static struct mm_region imx8m_mem_map[] = {
 
 struct mm_region *mem_map = imx8m_mem_map;
 
+void enable_caches(void)
+{
+       /*
+        * If OPTEE runs, remove OPTEE memory from MMU table to
+        * avoid speculative prefetch. OPTEE runs at the top of
+        * the first memory bank
+        */
+       if (rom_pointer[1])
+               imx8m_mem_map[5].size -= rom_pointer[1];
+
+       icache_enable();
+       dcache_enable();
+}
+
 static u32 get_cpu_variant_type(u32 type)
 {
        struct ocotp_regs *ocotp = (struct ocotp_regs *)OCOTP_BASE_ADDR;