[PATCH] rockchip: rk3399: pass platform parameter to TF-A by default

[Quentin Schulz]

Hi Jerome,

On 11/14/22 22:13, Jerome Forissier wrote:
> 
> 
> On 11/14/22 18:37, Quentin Schulz wrote:
>> From: Quentin Schulz <quentin.schulz at theobroma-systems.com>
>>
>> Long are gone the times TF-A couldn't handle the FDT passed by U-Boot.
>> Specifically, since commit e7b586987c0a ("rockchip: don't crash if we
>> get an FDT we can't parse") in TF-A, failure to parse the FDT will use
>> the fallback mechanism. This patch was merged in TF-A v2.4-rc0 from two
>> years ago.
>>
>> Therefore, let's finally pass the FDT to TF-A so that it can get the
>> serial configuration from U-Boot FDT instead of requiring the user to
>> patch TF-A hardcoded fallback values.
>>
>> Cc: Quentin Schulz <foss+uboot at 0leil.net>
>> Signed-off-by: Quentin Schulz <quentin.schulz at theobroma-systems.com>
>> ---
>> rockchip: rk3399: pass platform parameter to TF-A
>>
>> Finally pass the FDT address to TF-A since it now gracefully fallbacks to
>> hardcoded defaults if it cannot parse it. This allows us to avoid modifying
>> hardcoded values in TF-A to enable the console.
> 
> Does this mean that with this patch TF-A will properly set the baudrate of
> the console UART to 1.5MBd? I'm asking because I am about to send the

Yes. I tested on my Puma RK3399 which defaults to 115200 with the 
following patch:
diff --git a/arch/arm/dts/rk3399-puma-haikou-u-boot.dtsi 
b/arch/arm/dts/rk3399-puma-haikou-u-boot.dtsi
index d2349ae90e..1c8ec97d44 100644
--- a/arch/arm/dts/rk3399-puma-haikou-u-boot.dtsi
+++ b/arch/arm/dts/rk3399-puma-haikou-u-boot.dtsi
@@ -22,7 +22,7 @@
  	};

  	chosen {
-		stdout-path = "serial0:115200n8";
+		stdout-path = "serial0:1500000n8";
  		u-boot,spl-boot-order = \
  			"same-as-spl", &norflash, &sdhci, &sdmmc;
  	};
diff --git a/configs/puma-rk3399_defconfig b/configs/puma-rk3399_defconfig
index 91f31b37e8..0aa0c1d911 100644
--- a/configs/puma-rk3399_defconfig
+++ b/configs/puma-rk3399_defconfig
@@ -92,6 +92,7 @@ CONFIG_PWM_ROCKCHIP=y
  CONFIG_DM_RESET=y
  CONFIG_DM_RTC=y
  CONFIG_RTC_ISL1208=y
+CONFIG_BAUDRATE=1500000
  CONFIG_DEBUG_UART_SHIFT=2
  CONFIG_ROCKCHIP_SPI=y
  CONFIG_SYSRESET=y

and TF-A prints at that baudrate after reading it from the DT passed by 
U-Boot (I added my own debug messages in TF-A to validate this claim).

This is supported since v2.2, commit 30970e0f2979 ("rockchip: make uart 
baudrate configurable").

> following patch to TF-A (if I can figure out the Gerrit stuff that is...):
> 

Since I went through this yesterday:
Link your GitHub account to the Gerrit instance.
Add your public ssh key in 
https://review.trustedfirmware.org/settings/#SSHKeys
Then git clone the repo locally. For some reason the instructions in 
https://review.trustedfirmware.org/admin/repos/TF-A/trusted-firmware-a 
do not work for me, instead I did:
git clone "https://review.trustedfirmware.org/TF-A/trusted-firmware-a"
wget https://review.trustedfirmware.org/tools/hooks/commit-msg -O 
trusted-firmware-a/.git/hooks/commit-msg
chmod +x trusted-firmware-a/.git/hooks/commit-msg
then you should be able to push with:
git push origin HEAD:refs/for/integration -o topic=<some-topic>

> =============
>  From 51c1aa9277f6386b3a8055ad8ad582f894ab9230 Mon Sep 17 00:00:00 2001
> From: Jerome Forissier <jerome.forissier at linaro.org>
> Date: Thu, 10 Nov 2022 21:38:30 +0100
> Subject: [PATCH] rk3399: set console baudrate to 1500000
> 
> The default speed for the console UART of the rk3399 SoC is 1.5 MBaud.
> It is the value used by U-Boot so if TF-A has a different value there
> is no output when the boot switches from TPL to TF-A BL31 (note that
> OP-TEE which does not change the speed). The Rockchip loader aka flash
> helper (rk3399_loader_v1.20.119.bin [1][2]) also uses the same speed.
> Therefore set the default baudrate to 1500000.
> 

This has already been discussed, see discussion there:
https://developer.trustedfirmware.org/T762, I would suggest to try to 
revive the discussion there.

Cheers,
Quentin