[U-Boot] [PATCH v2 5/5] board: ge: bx50v3: Fix to meet LVDS display power on timing

Akshay Bhat akshay.bhat at timesys.com
Wed Apr 13 00:14:00 CEST 2016


On a reset/reboot, the display power needs to be off for atleast 500ms
before turning it back on. So add a delay to the boot process to meet
the display timing requirement.

Signed-off-by: Akshay Bhat <akshay.bhat at timesys.com>
Cc: Stefano Babic <sbabic at denx.de>
---
 board/ge/bx50v3/bx50v3.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/board/ge/bx50v3/bx50v3.c b/board/ge/bx50v3/bx50v3.c
index b6db91b..822fc35 100644
--- a/board/ge/bx50v3/bx50v3.c
+++ b/board/ge/bx50v3/bx50v3.c
@@ -472,6 +472,13 @@ static void setup_display_bx50v3(void)
 	struct mxc_ccm_reg *mxc_ccm = (struct mxc_ccm_reg *)CCM_BASE_ADDR;
 	struct iomuxc *iomux = (struct iomuxc *)IOMUXC_BASE_ADDR;
 
+	/* When a reset/reboot is performed the display power needs to be turned
+	 * off for atleast 500ms. The boot time is ~300ms, we need to wait for
+	 * an additional 200ms here. Unfortunately we use external PMIC for
+	 * doing the reset, so can not differentiate between POR vs soft reset
+	 */
+	mdelay(200);
+
 	/* IPU1 DI0 clock is 480/7 = 68.5 MHz */
 	setbits_le32(&mxc_ccm->cscmr2, MXC_CCM_CSCMR2_LDB_DI0_IPU_DIV);
 
-- 
2.8.1



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