Re: [PATCH] clk: qcom: ipq8074: fix PCI-E clock oops

[Stephen Boyd <sboyd@kernel.org>]

Quoting Robert Marko (2021-05-18 10:51:53)
> Fix PCI-E clock related kernel oops that are causes by missing
> parent_names.
> 
> Without the use of parent_names kernel will panic on
> clk_core_get_parent_by_index() due to a NULL pointer.
> 
> Without this earlycon is needed to even catch the OOPS as it will reset
> the board before serial is initialized.

Can you share the oops message here in the commit text?

> 
> Fixes: f0cfcf1ade20 ("clk: qcom: ipq8074: Add missing clocks for pcie")
> Signed-off-by: Robert Marko <robimarko@gmail.com>
> ---
>  drivers/clk/qcom/gcc-ipq8074.c | 11 +++++------
>  1 file changed, 5 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/clk/qcom/gcc-ipq8074.c b/drivers/clk/qcom/gcc-ipq8074.c
> index 0c619ed35c82..8d8b1717a203 100644
> --- a/drivers/clk/qcom/gcc-ipq8074.c
> +++ b/drivers/clk/qcom/gcc-ipq8074.c
> @@ -4357,8 +4357,7 @@ static struct clk_rcg2 pcie0_rchng_clk_src = {
>         .parent_map = gcc_xo_gpll0_map,
>         .clkr.hw.init = &(struct clk_init_data){
>                 .name = "pcie0_rchng_clk_src",
> -               .parent_hws = (const struct clk_hw *[]) {
> -                               &gpll0.clkr.hw },
> +               .parent_names = gcc_xo_gpll0,

This seems to imply that we need to have two parents but we didn't
realize that was the case. Ouch! Please use a struct clk_parent_data
array and then use the firmware name for XO and the clk_hw pointer for
gpll0.

>                 .num_parents = 2,
>                 .ops = &clk_rcg2_ops,
>         },
> @@ -4372,8 +4371,8 @@ static struct clk_branch gcc_pcie0_rchng_clk = {
>                 .enable_mask = BIT(1),
>                 .hw.init = &(struct clk_init_data){
>                         .name = "gcc_pcie0_rchng_clk",
> -                       .parent_hws = (const struct clk_hw *[]){
> -                               &pcie0_rchng_clk_src.clkr.hw,
> +                       .parent_names = (const char *[]){
> +                               "pcie0_rchng_clk_src",
>                         },
>                         .num_parents = 1,
>                         .flags = CLK_SET_RATE_PARENT,
> @@ -4390,8 +4389,8 @@ static struct clk_branch gcc_pcie0_axi_s_bridge_clk = {
>                 .enable_mask = BIT(0),
>                 .hw.init = &(struct clk_init_data){
>                         .name = "gcc_pcie0_axi_s_bridge_clk",
> -                       .parent_hws = (const struct clk_hw *[]){
> -                               &pcie0_axi_clk_src.clkr.hw,
> +                       .parent_names = (const char *[]){
> +                               "pcie0_axi_clk_src"

These two hunks can be dropped.