[U-Boot] [PATCH v2 15/20] Tegra2: Turn off power detect in board init

[Simon Glass]

From: Wei Ni <wni at nvidia.com>

Tegra core power rail has leakage voltage around 0.2V while system in
suspend mode. The source of the leakage should be coming from PMC power
detect logic for IO rails power detection.
That can be disabled by writing a '0' to PWR_DET_LATCH followed by writing '0'
to PWR_DET (APBDEV_PMC_PWR_DET_0).

Signed-off-by: Simon Glass <sjg at chromium.org>
---

 board/nvidia/common/board.c |   18 ++++++++++++++++++
 1 files changed, 18 insertions(+), 0 deletions(-)

diff --git a/board/nvidia/common/board.c b/board/nvidia/common/board.c
index d2eee6e..4e6a505 100644
--- a/board/nvidia/common/board.c
+++ b/board/nvidia/common/board.c
@@ -56,6 +56,21 @@ int timer_init(void)
 }
 
 /*
+ * Routine: power_det_init
+ * Description: turn off power detects
+ */
+static void power_det_init(void)
+{
+#if defined(CONFIG_TEGRA2)
+	struct pmc_ctlr *const pmc = (struct pmc_ctlr *)TEGRA2_PMC_BASE;
+
+	/* turn off power detects */
+	writel(0, &pmc->pmc_pwr_det_latch);
+	writel(0, &pmc->pmc_pwr_det);
+#endif
+}
+
+/*
  * Routine: board_init
  * Description: Early hardware init.
  */
@@ -73,6 +88,9 @@ int board_init(void)
 #endif
 	/* boot param addr */
 	gd->bd->bi_boot_params = (NV_PA_SDRAM_BASE + 0x100);
+
+	power_det_init();
+
 #ifdef CONFIG_TEGRA2_I2C
 #ifndef CONFIG_SYS_I2C_INIT_BOARD
 #error "You must define CONFIG_SYS_I2C_INIT_BOARD to use i2c on Nvidia boards"
-- 
1.7.7.3