On 11/15/2024 9:29 PM, Dmitry Baryshkov wrote:
On Fri, Nov 15, 2024 at 02:45:45PM +0530, Krishna Kurapati wrote:
Commit [1] introduced DP support to QMP driver. While doing so, the
dp and usb configuration structures were added to a combo_phy_cfg
structure. During probe, the match data is used to parse and identify the
dp and usb configs separately. While doing so, the usb_cfg variable
represents the configuration parameters for USB part of the phy (whether
it is DP-Cobo or Uni). during probe, one corner case of parsing usb_cfg
for Uni PHYs is left incomplete and it is left as NULL. This NULL variable
further percolates down to qmp_phy_create() call essentially getting
de-referenced and causing a crash.
The UNI PHY platforms don't have usb3-phy subnode. As such the usb_cfg
variable should not be used in the for_each_available_child_of_node()
loop.
Please provide details for the platform on which you observe the crash
and the backtrace.
I got this error when I started working on multiport support (begining
of 2023). Initially I tried testing on my code on 5.15, hence this patch
was raised on the same.
The 2 qmp phys on sa8195 and sa8295 (based on sc8280xp) are uni phy and
the following was the DT node that worked out for me on 5.15 codebase:
usb_1_qmpphy: ssphy@88eb000 {
compatible = "qcom,sm8150-qmp-usb3-uni-phy";
reg = <0x088eb000 0x200>;
#address-cells = <1>;
#size-cells = <1>;
ranges;
//status = "disabled";
clocks = <&gcc GCC_USB3_MP_PHY_AUX_CLK>,
<&rpmhcc RPMH_CXO_CLK>,
<&gcc GCC_USB3_SEC_CLKREF_CLK>,
<&gcc GCC_USB3_MP_PHY_COM_AUX_CLK>;
clock-names = "aux", "ref_clk_src", "ref", "com_aux";
resets = <&gcc GCC_USB3UNIPHY_PHY_MP0_BCR>,
<&gcc GCC_USB3_UNIPHY_MP0_BCR>;
reset-names = "phy", "common";
//vdda-phy-supply = <&L3C>;
vdda-pll-supply = <&L5E>;
usb_1_ssphy: usb3-phy@88eb200 {
reg = <0x088eb200 0x200>,
<0x088eb400 0x200>,
<0x088eb800 0x800>,
<0x088eb600 0x200>;
#clock-cells = <0>;
#phy-cells = <0>;
clocks = <&gcc GCC_USB3_MP_PHY_PIPE_0_CLK>;
clock-names = "pipe0";
clock-output-names = "usb3_uni_phy_pipe_clk_src";
};
};
I was hitting the bug when I write the DT above way on top of 5.15 baseline.
In 5.15.y, the SM8150 usb_2_qmpphy dT is as follows:
usb_2_qmpphy: phy@88eb000 {
compatible = "qcom,sm8150-qmp-usb3-uni-phy";
reg = <0 0x088eb000 0 0x200>;
status = "disabled";
#address-cells = <2>;
#size-cells = <2>;
ranges;
clocks = <&gcc GCC_USB3_SEC_PHY_AUX_CLK>,
<&rpmhcc RPMH_CXO_CLK>,
<&gcc GCC_USB3_SEC_CLKREF_CLK>,
<&gcc GCC_USB3_SEC_PHY_COM_AUX_CLK>;
clock-names = "aux", "ref_clk_src", "ref",
"com_aux";
resets = <&gcc GCC_USB3PHY_PHY_SEC_BCR>,
<&gcc GCC_USB3_PHY_SEC_BCR>;
reset-names = "phy", "common";
usb_2_ssphy: phy@88eb200 {
reg = <0 0x088eb200 0 0x200>,
<0 0x088eb400 0 0x200>,
<0 0x088eb800 0 0x800>,
<0 0x088eb600 0 0x200>;
#clock-cells = <0>;
#phy-cells = <0>;
clocks = <&gcc GCC_USB3_SEC_PHY_PIPE_CLK>;
clock-names = "pipe0";
clock-output-names =
"usb3_uni_phy_pipe_clk_src";
};
};
IIRC, when I tried using the above sm8150 dt on 5.15.y, the phy_create
was (either not getting called) or crashing. Probably because
"of_node_name_eq()" didn't find either "dp-phy" or "usb3-phy" and cfg
variable was NULL.
I can try reproducing the issue and get back again in a week.
Apologies if I have misunderstood something and this patch doesn't make
sense. Let me know if I have made any mistake anywhere (either in my DT)
or in understanding.
Regards,
Krishna,
