[PATCH] armv7: ls102xa: make QSPI clock selection optional during SoC init

[Mario Kicherer]

To improve startup times when booting from QSPI flash, the QSPI frequency
can be configured very early in the boot process [1] to reduce loading
times of U-Boot itself. This patch adds an option to disable setting the
frequency to a default value during SoC initialization.

[1] https://www.nxp.com/docs/en/application-note/AN12279.pdf

Signed-off-by: Mario Kicherer <dev at kicherer.org>
---
 arch/arm/cpu/armv7/ls102xa/Kconfig | 9 +++++++++
 arch/arm/cpu/armv7/ls102xa/soc.c   | 4 ++--
 2 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/arch/arm/cpu/armv7/ls102xa/Kconfig b/arch/arm/cpu/armv7/ls102xa/Kconfig
index e75a895e00..f6b07b6026 100644
--- a/arch/arm/cpu/armv7/ls102xa/Kconfig
+++ b/arch/arm/cpu/armv7/ls102xa/Kconfig
@@ -98,4 +98,13 @@ config SYS_FSL_IFC_BANK_COUNT
 config SYS_FSL_ERRATUM_A008407
 	bool
 
+config SYS_FSL_QSPI_SKIP_CLKSEL
+	bool "Skip setting QSPI clock during SoC init"
+	default 0
+	help
+	   To improve startup times when booting from QSPI flash, the QSPI
+	   frequency can be set very early in the boot process. If this option
+	   is enabled, the QSPI frequency will not be changed by U-Boot during
+	   SoC initialization.
+
 endmenu
diff --git a/arch/arm/cpu/armv7/ls102xa/soc.c b/arch/arm/cpu/armv7/ls102xa/soc.c
index 21570204b0..84d4ea3a8f 100644
--- a/arch/arm/cpu/armv7/ls102xa/soc.c
+++ b/arch/arm/cpu/armv7/ls102xa/soc.c
@@ -169,8 +169,8 @@ int arch_soc_init(void)
 #ifdef CONFIG_LAYERSCAPE_NS_ACCESS
 	enable_layerscape_ns_access();
 #endif
-	
-#if defined(CONFIG_FSL_QSPI)
+
+#if defined(CONFIG_FSL_QSPI) && !defined(CONFIG_SYS_FSL_QSPI_SKIP_CLKSEL)
 	out_be32(&scfg->qspi_cfg, SCFG_QSPI_CLKSEL);
 #endif
 
-- 
2.34.1