Hi Xavier,
On 2022/7/2 02:59, Xavier Drudis Ferran wrote:
arch/arm/dts/rk3399.dtsi has a node
usb_host0_ehci: usb@fe380000 {
compatible = "generic-ehci";
with clocks:
clocks = <&cru HCLK_HOST0>, <&cru HCLK_HOST0_ARB>,
<&u2phy0>;
The first 2 refer to nodes with class UCLASS_CLK, but &u2phy0
has class UCLASS_PHY.
u2phy0: usb2phy@e450 {
compatible = "rockchip,rk3399-usb2phy";
Since clk_get_bulk() only looks for devices with UCLASS_CLK,
it fails with -ENODEV and then ehci_usb_probe() aborts.
The consequence is peripherals connected to a USB 2 port (e.g. in a
Rock Pi 4 the white port, nearer the edge) not being detected.
They're detected if CONFIG_USB_OHCI_GENERIC is selected in Kconfig,
because ohci_usb_probe() does not abort when one clk_get_by_index()
fails, but then they work in USB 1 mode,.
rk3399.dtsi comes from linux and the u2phy0 was added[1] to the clock
list in:
commit b5d1c57299734f5b54035ef2e61706b83041f20c
Author: William wu <w...@rock-chips.com>
Date: Wed Dec 21 18:41:05 2016 +0800
arm64: dts: rockchip: add u2phy clock for ehci and ohci of rk3399
We found that the suspend process was blocked when it run into
ehci/ohci module due to clk-480m of usb2-phy was disabled.
[...]
Suspend concerns don't apply to U-Boot, and the problem with U-Boot
failing to probe EHCI doesn't apply to linux, because in linux
rockchip_usb2phy_clk480m_register makes u2phy0 a proper clock provider
when called by rockchip_usb2phy_probe().
So I can think of a few alternative solutions:
1- Change ehci_usb_probe() to make it more similar to
ohci_usb_probe(), and survive failure to get one clock. Looks a
little harder, and I don't know whether it could break something if
it ignored a clock that was important for something else than
suspend.
2- Change rk3399.dtsi effecttively reverting the linux commit
b5d1c57299734f5b54035ef2e61706b83041f20c. This dealigns the .dtsi
from linux and seems fragile at the next synchronisation.
3- Change the clock list in rk3399-u-boot.dtsi or somewhere else.
This survives .dts* sync but may survive "too much" and miss some
change from linux that we might want.
4- Enable CONFIG_USB_OHCI_GENERIC and use the ports in USB 1 mode.
This would need to be made for all boards using rk3399. In a
simple test reading one file from USB storage it gave 769.5 KiB/s
instead of 20.5 MiB/s with solution 2.
5- Trying to replicate linux and have usb2phy somehow provide a clk,
or have a separate clock device for usb2phy in addition to the phy
device. I just can't seem to imagine how to achieve this with the
U-Boot driver model, maybe because of my limited familiarity with
it.
This patch is option 3. Looked like the simplest and most performant.
But it might not be what's wanted, so comments wellcome.
The idea for dtsi now is to sync the kernel and U-Boot dts, and Linux
distribution will
use the dts from U-Boot. If we change the dts property in -u-boot.dts,
it will also pass
to kernel, which make kernel function not available. So we would like to
sync the driver
for kernel and u-boot to use the same dts nodes.
So we can try option 1, output warning instead of error return for clock
get fail, since the clock
driver for kernel and u-boot are totally different.
Thanks,
- Kever
Link: [1] https://lkml.kernel.org/lkml/1731551.Q6cHK6n5ZM@phil/T/
Cc: Simon Glass <s...@chromium.org>
Cc: Philipp Tomsich <philipp.toms...@vrull.eu>
Cc: Kever Yang <kever.y...@rock-chips.com>
Cc: Lukasz Majewski <lu...@denx.de>
Cc: Sean Anderson <sean...@gmail.com>
Cc: Marek Vasut <ma...@denx.de>
Signed-off-by: Xavier Drudis Ferran <xdru...@tinet.cat>
---
arch/arm/dts/rk3399-u-boot.dtsi | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/arch/arm/dts/rk3399-u-boot.dtsi b/arch/arm/dts/rk3399-u-boot.dtsi
index 716b9a433a..63c7b10405 100644
--- a/arch/arm/dts/rk3399-u-boot.dtsi
+++ b/arch/arm/dts/rk3399-u-boot.dtsi
@@ -147,3 +147,11 @@
&vopl {
u-boot,dm-pre-reloc;
};
+
+&usb_host0_ehci {
+ clocks = <&cru HCLK_HOST0>, <&cru HCLK_HOST0_ARB>;
+};
+
+&usb_host1_ehci {
+ clocks = <&cru HCLK_HOST1>, <&cru HCLK_HOST1_ARB>;
+};
