[U-Boot] [PATCH 4/5] ARM64: zynqmp: Fix secondary bootmode enabling

[Michal Simek]

Do not setup use_alt bit which copy alternative boot mode to
boot mode. The reason is that this bit is cleared after POR
but not after any software reset which will cause
that after SW reset bootrom will look for different boot image.

This patch setups alternative boot mode selection (purely SW
handling) and extends code to read this alternative boot mode first and
use it if it is setup.

Signed-off-by: Michal Simek <michal.simek at xilinx.com>
---

 arch/arm/cpu/armv8/zynqmp/spl.c | 6 ++++--
 board/xilinx/zynqmp/zynqmp.c    | 3 +++
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/arch/arm/cpu/armv8/zynqmp/spl.c b/arch/arm/cpu/armv8/zynqmp/spl.c
index 04e190537d15..bdbd61380ab7 100644
--- a/arch/arm/cpu/armv8/zynqmp/spl.c
+++ b/arch/arm/cpu/armv8/zynqmp/spl.c
@@ -69,12 +69,14 @@ u32 spl_boot_device(void)
 
 #if defined(CONFIG_SPL_ZYNQMP_ALT_BOOTMODE_ENABLED)
 	/* Change default boot mode at run-time */
-	writel(BOOT_MODE_USE_ALT |
-	       CONFIG_SPL_ZYNQMP_ALT_BOOTMODE << BOOT_MODE_ALT_SHIFT,
+	writel(CONFIG_SPL_ZYNQMP_ALT_BOOTMODE << BOOT_MODE_ALT_SHIFT,
 	       &crlapb_base->boot_mode);
 #endif
 
 	reg = readl(&crlapb_base->boot_mode);
+	if (reg >> BOOT_MODE_ALT_SHIFT)
+		reg >>= BOOT_MODE_ALT_SHIFT;
+
 	bootmode = reg & BOOT_MODES_MASK;
 
 	switch (bootmode) {
diff --git a/board/xilinx/zynqmp/zynqmp.c b/board/xilinx/zynqmp/zynqmp.c
index df72516239dc..cef1f6a13aee 100644
--- a/board/xilinx/zynqmp/zynqmp.c
+++ b/board/xilinx/zynqmp/zynqmp.c
@@ -335,6 +335,9 @@ int board_late_init(void)
 	}
 
 	reg = readl(&crlapb_base->boot_mode);
+	if (reg >> BOOT_MODE_ALT_SHIFT)
+		reg >>= BOOT_MODE_ALT_SHIFT;
+
 	bootmode = reg & BOOT_MODES_MASK;
 
 	puts("Bootmode: ");
-- 
1.9.1