[PATCH 2/8] stm32mp: update the mmu configuration for SPL and prereloc

[Patrick Delaunay]

Overidde the weak function dram_bank_mmu_setup() to set the DDR
(preloc case) or the SYSRAM (in SPL case) executable before to enable
the MMU and configure DACR.

This weak function is called in dcache_enable/mmu_setup.

This patchs avoids a permission access issue when the DDR is marked
executable (by calling mmu_set_region_dcache_behaviour with
DCACHE_DEFAULT_OPTION) after MMU setup and domain access permission
activation with DACR in dcache_enable.

Signed-off-by: Patrick Delaunay <patrick.delaunay at foss.st.com>
---

 arch/arm/mach-stm32mp/cpu.c | 40 +++++++++++++++++++++++++++----------
 1 file changed, 30 insertions(+), 10 deletions(-)

diff --git a/arch/arm/mach-stm32mp/cpu.c b/arch/arm/mach-stm32mp/cpu.c
index 717f80e9ff..030066dc7c 100644
--- a/arch/arm/mach-stm32mp/cpu.c
+++ b/arch/arm/mach-stm32mp/cpu.c
@@ -210,6 +210,35 @@ u32 get_bootmode(void)
 		    TAMP_BOOT_MODE_SHIFT;
 }
 
+/*
+ * weak function overidde: set the DDR/SYSRAM executable before to enable the
+ * MMU and configure DACR, for early early_enable_caches (SPL or pre-reloc)
+ */
+void dram_bank_mmu_setup(int bank)
+{
+	struct bd_info *bd = gd->bd;
+	int	i;
+	phys_addr_t start;
+	phys_size_t size;
+
+	if (IS_ENABLED(CONFIG_SPL_BUILD)) {
+		start = ALIGN_DOWN(STM32_SYSRAM_BASE, MMU_SECTION_SIZE);
+		size = ALIGN(STM32_SYSRAM_SIZE, MMU_SECTION_SIZE);
+	} else if (gd->flags & GD_FLG_RELOC) {
+		/* bd->bi_dram is available only after relocation */
+		start = bd->bi_dram[bank].start;
+		size =  bd->bi_dram[bank].size;
+	} else {
+		/* mark cacheable and executable the beggining of the DDR */
+		start = STM32_DDR_BASE;
+		size = CONFIG_DDR_CACHEABLE_SIZE;
+	}
+
+	for (i = start >> MMU_SECTION_SHIFT;
+	     i < (start >> MMU_SECTION_SHIFT) + (size >> MMU_SECTION_SHIFT);
+	     i++)
+		set_section_dcache(i, DCACHE_DEFAULT_OPTION);
+}
 /*
  * initialize the MMU and activate cache in SPL or in U-Boot pre-reloc stage
  * MMU/TLB is updated in enable_caches() for U-Boot after relocation
@@ -225,17 +254,8 @@ static void early_enable_caches(void)
 	gd->arch.tlb_size = PGTABLE_SIZE;
 	gd->arch.tlb_addr = (unsigned long)&early_tlb;
 
+	/* enable MMU (default configuration) */
 	dcache_enable();
-
-	if (IS_ENABLED(CONFIG_SPL_BUILD))
-		mmu_set_region_dcache_behaviour(
-			ALIGN_DOWN(STM32_SYSRAM_BASE, MMU_SECTION_SIZE),
-			ALIGN(STM32_SYSRAM_SIZE, MMU_SECTION_SIZE),
-			DCACHE_DEFAULT_OPTION);
-	else
-		mmu_set_region_dcache_behaviour(STM32_DDR_BASE,
-						CONFIG_DDR_CACHEABLE_SIZE,
-						DCACHE_DEFAULT_OPTION);
 }
 
 /*
-- 
2.17.1