arm: mvebu: Move internal registers in arch_very_early_init() function

Moving of internal registers from INTREG_BASE_ADDR_REG to SOC_REGS_PHY_BASE
needs to be done very early, prior calling any function which may touch
internal registers, like debug_uart_init().

So do it earlier in arch_very_early_init() instead of arch_cpu_init().

Movement is done in proper U-Boot, not in SPL. SPL may return to bootrom
and bootrom requires internal registers at (old) expected location.

Signed-off-by: Pali Rohár <pali@kernel.org>
Reviewed-by: Stefan Roese <sr@denx.de>

diff --git a/arch/arm/mach-mvebu/Kconfig b/arch/arm/mach-mvebu/Kconfig
index c764439..a81b8e2 100644 (file)
--- a/arch/arm/mach-mvebu/Kconfig
+++ b/arch/arm/mach-mvebu/Kconfig
@@ -16,6 +16,7 @@ config ARMADA_32BIT
        select SUPPORT_SPL
        select TRANSLATION_OFFSET
        select SPL_SYS_NO_VECTOR_TABLE if SPL
+       select ARCH_VERY_EARLY_INIT
 
 # ARMv7 SoCs...
 config ARMADA_375

diff --git a/arch/arm/mach-mvebu/Makefile b/arch/arm/mach-mvebu/Makefile
index 1b45188..8bd2246 100644 (file)
--- a/arch/arm/mach-mvebu/Makefile
+++ b/arch/arm/mach-mvebu/Makefile
@@ -21,6 +21,7 @@ else # CONFIG_ARCH_KIRKWOOD
 
 obj-y  = cpu.o
 obj-y  += dram.o
+obj-y  += lowlevel.o
 obj-$(CONFIG_DM_RESET) += system-controller.o
 ifndef CONFIG_SPL_BUILD
 obj-$(CONFIG_ARMADA_375) += ../../../drivers/ddr/marvell/axp/xor.o

diff --git a/arch/arm/mach-mvebu/cpu.c b/arch/arm/mach-mvebu/cpu.c
index 1e89377..173d95a 100644 (file)
--- a/arch/arm/mach-mvebu/cpu.c
+++ b/arch/arm/mach-mvebu/cpu.c
@@ -413,20 +413,7 @@ static void update_sdram_window_sizes(void)
        }
 }
 
-void mmu_disable(void)
-{
-       asm volatile(
-               "mrc p15, 0, r0, c1, c0, 0\n"
-               "bic r0, #1\n"
-               "mcr p15, 0, r0, c1, c0, 0\n");
-}
-
 #ifdef CONFIG_ARCH_CPU_INIT
-static void set_cbar(u32 addr)
-{
-       asm("mcr p15, 4, %0, c15, c0" : : "r" (addr));
-}
-
 #define MV_USB_PHY_BASE                        (MVEBU_AXP_USB_BASE + 0x800)
 #define MV_USB_PHY_PLL_REG(reg)                (MV_USB_PHY_BASE | (((reg) & 0xF) << 2))
 #define MV_USB_X3_BASE(addr)           (MVEBU_AXP_USB_BASE | BIT(11) | \
@@ -476,24 +463,6 @@ int arch_cpu_init(void)
        struct pl310_regs *const pl310 =
                (struct pl310_regs *)CONFIG_SYS_PL310_BASE;
 
-       /*
-        * Only with disabled MMU its possible to switch the base
-        * register address on Armada 38x. Without this the SDRAM
-        * located at >= 0x4000.0000 is also not accessible, as its
-        * still locked to cache.
-        */
-       mmu_disable();
-
-       /* Linux expects the internal registers to be at 0xf1000000 */
-       writel(SOC_REGS_PHY_BASE, INTREG_BASE_ADDR_REG);
-       set_cbar(SOC_REGS_PHY_BASE + 0xC000);
-
-       /*
-        * From this stage on, the SoC detection is working. As we have
-        * configured the internal register base to the value used
-        * in the macros / defines in the U-Boot header (soc.h).
-        */
-
        if (mvebu_soc_family() == MVEBU_SOC_A38X) {
                /*
                 * To fully release / unlock this area from cache, we need

diff --git a/arch/arm/mach-mvebu/lowlevel.S b/arch/arm/mach-mvebu/lowlevel.S
new file mode 100644 (file)
index 0000000..2491310
--- /dev/null
+++ b/arch/arm/mach-mvebu/lowlevel.S
@@ -0,0 +1,27 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+
+#include <config.h>
+#include <linux/linkage.h>
+
+ENTRY(arch_very_early_init)
+#ifdef CONFIG_ARMADA_38X
+       /*
+        * Only with disabled MMU its possible to switch the base
+        * register address on Armada 38x. Without this the SDRAM
+        * located at >= 0x4000.0000 is also not accessible, as its
+        * still locked to cache.
+        */
+       mrc     p15, 0, r0, c1, c0, 0
+       bic     r0, #1
+       mcr     p15, 0, r0, c1, c0, 0
+#endif
+
+       /* Move internal registers from INTREG_BASE_ADDR_REG to SOC_REGS_PHY_BASE */
+       ldr     r0, =SOC_REGS_PHY_BASE
+       ldr     r1, =INTREG_BASE_ADDR_REG
+       str     r0, [r1]
+       add     r0, r0, #0xC000
+       mcr     p15, 4, r0, c15, c0
+
+       bx lr
+ENDPROC(arch_very_early_init)