[U-Boot] [PATCH] serial, ns16550: bugfix: ns16550 fifo not enabled

Heiko Schocher hs at denx.de
Tue Jan 10 08:08:51 CET 2017


commit: 65f83802b7a5b "serial: 16550: Add getfcr accessor"
breaks u-boot commandline working with long commands
sending to the board.

Since the above patch, you have to setup the fcr register.

For board/archs which enable OF_PLATDATA, the new field
fcr in struct ns16550_platdata is not filled with a
default value ...

This leads in not setting up the uarts fifo, which ends
in problems, when you send long commands to u-boots
commandline.

Detected this issue with automated tbot tests on am335x
based shc board.

The error does not popup, if you type commands. You need
to copy&paste a long command to u-boots commandshell
(or send a long command with tbot)

Possible boards/plattforms with problems:
./arch/arm/cpu/arm926ejs/lpc32xx/devices.c
./arch/arm/mach-tegra/board.c
./board/isee/igep00x0/igep00x0.c
./board/overo/overo.c
./board/quipos/cairo/cairo.c
./board/logicpd/omap3som/omap3logic.c
./board/logicpd/zoom1/zoom1.c
./board/timll/devkit8000/devkit8000.c
./board/lg/sniper/sniper.c
./board/ti/beagle/beagle.c
./drivers/serial/serial_rockchip.c

This patch fixes only:
./arch/arm/mach-omap2/am33xx/board.c

Signed-off-by: Heiko Schocher <hs at denx.de>
---

 arch/arm/mach-omap2/am33xx/board.c | 23 +++++++++++++++++------
 1 file changed, 17 insertions(+), 6 deletions(-)

diff --git a/arch/arm/mach-omap2/am33xx/board.c b/arch/arm/mach-omap2/am33xx/board.c
index 581c0ab..a0ce62c 100644
--- a/arch/arm/mach-omap2/am33xx/board.c
+++ b/arch/arm/mach-omap2/am33xx/board.c
@@ -39,15 +39,26 @@
 DECLARE_GLOBAL_DATA_PTR;
 
 #if !CONFIG_IS_ENABLED(OF_CONTROL)
+/* Clear & enable FIFOs */
+#define UART_FCRVAL (UART_FCR_FIFO_EN |	\
+		     UART_FCR_RXSR |	\
+		     UART_FCR_TXSR)
+
 static const struct ns16550_platdata am33xx_serial[] = {
-	{ .base = CONFIG_SYS_NS16550_COM1, .reg_shift = 2, .clock = CONFIG_SYS_NS16550_CLK },
+	{ .base = CONFIG_SYS_NS16550_COM1, .reg_shift = 2,
+	  .clock = CONFIG_SYS_NS16550_CLK, .fcr = UART_FCRVAL },
 # ifdef CONFIG_SYS_NS16550_COM2
-	{ .base = CONFIG_SYS_NS16550_COM2, .reg_shift = 2, .clock = CONFIG_SYS_NS16550_CLK },
+	{ .base = CONFIG_SYS_NS16550_COM2, .reg_shift = 2,
+	  .clock = CONFIG_SYS_NS16550_CLK, .fcr = UART_FCRVAL },
 #  ifdef CONFIG_SYS_NS16550_COM3
-	{ .base = CONFIG_SYS_NS16550_COM3, .reg_shift = 2, .clock = CONFIG_SYS_NS16550_CLK },
-	{ .base = CONFIG_SYS_NS16550_COM4, .reg_shift = 2, .clock = CONFIG_SYS_NS16550_CLK },
-	{ .base = CONFIG_SYS_NS16550_COM5, .reg_shift = 2, .clock = CONFIG_SYS_NS16550_CLK },
-	{ .base = CONFIG_SYS_NS16550_COM6, .reg_shift = 2, .clock = CONFIG_SYS_NS16550_CLK },
+	{ .base = CONFIG_SYS_NS16550_COM3, .reg_shift = 2,
+	  .clock = CONFIG_SYS_NS16550_CLK, .fcr = UART_FCRVAL },
+	{ .base = CONFIG_SYS_NS16550_COM4, .reg_shift = 2,
+	  .clock = CONFIG_SYS_NS16550_CLK, .fcr = UART_FCRVAL },
+	{ .base = CONFIG_SYS_NS16550_COM5, .reg_shift = 2,
+	  .clock = CONFIG_SYS_NS16550_CLK, .fcr = UART_FCRVAL },
+	{ .base = CONFIG_SYS_NS16550_COM6, .reg_shift = 2,
+	  .clock = CONFIG_SYS_NS16550_CLK, .fcr = UART_FCRVAL },
 #  endif
 # endif
 };
-- 
2.7.4



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