Re: [U-Boot] [PATCH V3 15/27] imx8m: Fix MMU table issue for OPTEE memory

Hi Peng,

On Tue, Aug 27, 2019 at 9:38 AM Peng Fan peng.fan@nxp.com wrote:

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

arch/arm/mach-imx/imx8m/soc.c | 20 ++++++++++++++++++-- 1 file changed, 18 insertions(+), 2 deletions(-)

diff --git a/arch/arm/mach-imx/imx8m/soc.c b/arch/arm/mach-imx/imx8m/soc.c index 5115471eff..dd393b581b 100644 --- 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; -- 2.16.4

---

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Unfortunately, I'm still facing a similar issue when OP-TEE is loaded on iMX8MM-based module, despite BL32_BASE(0xbe000000) + BL32_SIZE(0x2000000) region is excluded. Based on debug ouput the latest one is: .... idx=2 PTE 00000000bfff7010 at level 1: bfffd003 Checking if pte fits for virt=bde00000 size=200000 blocksize=40000000 addr=bde00000 level=2 idx=2 PTE 00000000bfff7010 at level 1: bfffd003 idx=1ef PTE 00000000bfffdf78 at level 2: 0 Checking if pte fits for virt=bde00000 size=200000 blocksize=200000 Setting PTE 00000000bfffdf78 to block virt=bde00000

U-Boot hangs just after writing to System Control Register in arch/arm/cpu/armv8/cache_v8.c:419:

/* enable the mmu */ set_sctlr(get_sctlr() | CR_M);

In my setup mainline U-Boot/TF-A/OP-TEE are used: u-boot: 133276f14a ("Merge branch '2020-02-25-master-imports'") tf-a: 6e46981f84 ("Merge "Update pathnames in maintainers.rst file" into integration") op-tee: a67dc424ff ("ta: pkcs11: API for slot/token information")

OP-TEE is compiled with these flags: CFG_ARM64_core=y CFG_NXP_CAAM=n CFG_NXPCRYPT=n PLATFORM=imx-mx8mmevk CFG_TEE_CORE_LOG_LEVEL=4 DEBUG=y CFG_TEE_CORE_DEBUG=y

With DCACHE disabled obviously everything works. Also I don't face any issues if TF-A is compiled without SPD=opteed.

Maybe it rings the bell and you already saw similar issues before?

Thanks