[U-Boot] [PATCH 13/22] imx8m: Fix MMU table issue for OPTEE memory

Peng Fan peng.fan at nxp.com
Fri Aug 9 04:15:21 UTC 2019


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 at 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



More information about the U-Boot mailing list