[U-Boot] [PATCH V2] ppc4xx: Canyonlands: Fix USB host PHY reset sequence

Dave Mitchell dmitchell at appliedmicro.com
Mon Dec 14 22:04:53 CET 2009


Current de-assert reset is not sufficient for the USB PHY reset
on some Canyonlands platforms. The patch adds an assert/de-assert
sequence. This addresses a USB detection problem for devices
attached prior to power-up. The delay lengths are needed for
power to the PHY to stabilize.

Signed-off-by: Jeff Mann <MannJ at embeddedplanet.com>
Signed-off-by: Dave Mitchell <dmitchell at appliedmicro.com>
Acked-by: Tirumala Reddy Marri <tmarri at appliedmicro.com>
---
v1->v2: fixed typo

 board/amcc/canyonlands/canyonlands.c |    5 ++++-
 1 files changed, 4 insertions(+), 1 deletions(-)

diff --git a/board/amcc/canyonlands/canyonlands.c b/board/amcc/canyonlands/canyonlands.c
index 13a0dac..6c61122 100644
--- a/board/amcc/canyonlands/canyonlands.c
+++ b/board/amcc/canyonlands/canyonlands.c
@@ -177,8 +177,11 @@ int board_early_init_f(void)
 	/* Remove NOR-FLASH, NAND-FLASH & EEPROM hardware write protection */
 	out_8((void *)CONFIG_SYS_BCSR_BASE + 5, 0);
 
-	/* Enable USB host & USB-OTG */
+	/* Enable USB host & USB-OTG;force assert,then de-assert PHY reset */
+	out_8((void *)CONFIG_SYS_BCSR_BASE + 7, 1);
+	mdelay(100);
 	out_8((void *)CONFIG_SYS_BCSR_BASE + 7, 0);
+	mdelay(100);
 
 	mtsdr(SDR0_SRST1, 0);	/* Pull AHB out of reset default=1 */
 
-- 
1.6.3.2



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