trusted-firmware-a: use 1500000 baud for serial console

TF-A runs between two u-boot stages which both uses 1500000 baud, it
just makes no sense to use the same UART at a different rate.

Here is a sample session with the successive stages, with TF-A artificially
separated for emphasis:

 [20210406-175438.135934] U-Boot TPL 2021.01 (Jan 11 2021 - 18:11:43)
 [20210406-175438.135956] Channel 0: DDR3, 933MHz
 [20210406-175438.236974] BW=32 Col=10 Bk=8 CS0 Row=15 CS=1 Die BW=16 Size=1024MB
 [20210406-175438.237000] Channel 1: DDR3, 933MHz
 [20210406-175438.237004] BW=32 Col=10 Bk=8 CS0 Row=15 CS=1 Die BW=16 Size=1024MB
 [20210406-175438.237008] 256B stride
 [20210406-175438.237012] Trying to boot from BOOTROM
 [20210406-175438.237015] Returning to boot ROM...
 [20210406-175438.237018]
 [20210406-175438.573394] U-Boot SPL 2021.01 (Jan 11 2021 - 18:11:43 +0000)
 [20210406-175438.573431] Trying to boot from MMC1

 [20210406-175438.589254] NOTICE:  BL31: v2.3():v2.3-dirty
 [20210406-175440.534055] NOTICE:  BL31: Built : 15:56:43, Apr 20 2020

 [20210406-175441.393423] U-Boot 2021.01 (Jan 11 2021 - 18:11:43 +0000)
 [20210406-175441.393429]
 [20210406-175441.393433] SoC: Rockchip rk3399

Signed-off-by: Yann Dirson <yann@blade-group.com>
This commit is contained in:
Yann Dirson 2021-04-08 09:34:02 +02:00 committed by Trevor Woerner
parent cd11f61a51
commit d47180f7f6
2 changed files with 41 additions and 0 deletions

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@ -0,0 +1,36 @@
From 840d6b6420e1fd8cdf6e4de7fa58a6f8de151622 Mon Sep 17 00:00:00 2001
From: Yann Dirson <yann@blade-group.com>
Date: Tue, 6 Apr 2021 17:28:45 +0200
Subject: [PATCH] Set serial console baudrate back to 1500000.
Upstream-Status: Inappropriate[other]
TF-A runs between two u-boot stages which both uses 1500000 baud, it
just makes no sense to use the same UART at a different rate.
This effectively reverts part of 0c05748bdebfad9fa43a80962186438bb8fbce62.
Main reason for that change stated in https://developer.trustedfirmware.org/T762
is ChromeOS compatibility.
Looks like this patch may become unnecessary in the future, when
u-boot and TF-A get to communicate this value.
---
plat/rockchip/rk3399/rk3399_def.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/plat/rockchip/rk3399/rk3399_def.h b/plat/rockchip/rk3399/rk3399_def.h
index ba83242eb..8d6ecfbe6 100644
--- a/plat/rockchip/rk3399/rk3399_def.h
+++ b/plat/rockchip/rk3399/rk3399_def.h
@@ -17,7 +17,7 @@
/**************************************************************************
* UART related constants
**************************************************************************/
-#define RK3399_BAUDRATE 115200
+#define RK3399_BAUDRATE 1500000
#define RK3399_UART_CLOCK 24000000
/******************************************************************************
--
2.30.2

View File

@ -4,3 +4,8 @@ DEPENDS_append_rk3399 = " virtual/arm-none-eabi-gcc-native"
COMPATIBLE_MACHINE_append_rk3399 = "|rk3399"
COMPATIBLE_MACHINE_append_rk3328 = "|rk3328"
FILESEXTRAPATHS_prepend := "${THISDIR}/files:"
SRC_URI += "\
file://serial-console-baudrate.patch \
"