@@ -56,4 +56,10 @@ config DEFINE_TCM_OCM_MMAP
This option if enabled defines the TCM and OCM memory and its
memory attributes in MMU table entry.
+config VERSAL_NO_DDR
+ bool "Disable DDR MMU mapping"
+ help
+ This option configures MMU with no DDR to avoid speculative
+ access to DDR memory where DDR is not present.
+
endif
@@ -81,6 +81,15 @@ void mem_map_fill(void)
if (!gd->bd->bi_dram[i].size)
break;
+#if defined(CONFIG_VERSAL_NO_DDR)
+ if (gd->bd->bi_dram[i].start < 0x80000000UL ||
+ gd->bd->bi_dram[i].start > 0x100000000UL) {
+ printf("Ignore caches over %llx/%llx\n",
+ gd->bd->bi_dram[i].start,
+ gd->bd->bi_dram[i].size);
+ continue;
+ }
+#endif
versal_mem_map[banks].virt = gd->bd->bi_dram[i].start;
versal_mem_map[banks].phys = gd->bd->bi_dram[i].start;
versal_mem_map[banks].size = gd->bd->bi_dram[i].size;
Similar change was done in past by commit 3b644a3c2f69 ("arm64: zynqmp: Provide a config to not map DDR region in MMU table"). Signed-off-by: Michal Simek <michal.simek at xilinx.com> --- arch/arm/mach-versal/Kconfig | 6 ++++++ arch/arm/mach-versal/cpu.c | 9 +++++++++ 2 files changed, 15 insertions(+)