[PATCH v2 2/2] mx7ulp: Only enable LDO if it is not already enabled

Fabio Estevam
2020-02-03T12:01:09Z

LDO mode may be already enabled by the ROM and enabling it again
can cause U-Boot to hang.

Avoid this problem by only enabling LDO mode if it is initially disabled.

Reported-by: Jorge Ramirez-Ortiz <jorge@foundries.io>
Signed-off-by: Fabio Estevam <festevam@gmail.com>
Tested-by: Jorge Ramirez-Ortiz <jorge@foundries.io>
---
Changes since v1:
- Drop the define changes as they are duplicated (Stefano).

arch/arm/mach-imx/mx7ulp/soc.c | 25 ++++++++++++++-----------
1 file changed, 14 insertions(+), 11 deletions(-)

diff --git a/arch/arm/mach-imx/mx7ulp/soc.c b/arch/arm/mach-imx/mx7ulp/soc.c
index d8d691692c..0d39dab7ea 100644
--- a/arch/arm/mach-imx/mx7ulp/soc.c
+++ b/arch/arm/mach-imx/mx7ulp/soc.c
@@ -118,12 +118,26 @@ void init_wdog(void)
disable_wdog(WDG2_RBASE);
}

+static bool ldo_mode_is_enabled(void)
+{
+ unsigned int reg;
+
+ reg = readl(PMC0_BASE_ADDR + PMC0_CTRL);
+ if (reg & PMC0_CTRL_LDOEN)
+ return true;
+ else
+ return false;
+}
+
#if !defined(CONFIG_SPL) || (defined(CONFIG_SPL) && defined(CONFIG_SPL_BUILD))
#if defined(CONFIG_LDO_ENABLED_MODE)
static void init_ldo_mode(void)
{
unsigned int reg;

+ if (ldo_mode_is_enabled())
+ return;
+
/* Set LDOOKDIS */
setbits_le32(PMC0_BASE_ADDR + PMC0_CTRL, PMC0_CTRL_LDOOKDIS);

@@ -193,17 +207,6 @@ const char *get_imx_type(u32 imxtype)
return "7ULP";
}

-static bool ldo_mode_is_enabled(void)
-{
- unsigned int reg;
-
- reg = readl(PMC0_BASE_ADDR + PMC0_CTRL);
- if (reg & PMC0_CTRL_LDOEN)
- return true;
- else
- return false;
-}
-
int print_cpuinfo(void)
{
u32 cpurev;
--
2.17.1