2018-12-13 17:01:08

by Jeffrey Hugo

Subject: [PATCH] clk: qcom: Leave mmss noc on for 8998

Similar to other qcom targets, gcc_mmss_noc_cfg_ahb_clk should not be
disabled. Any mmss access depends on this clock, and its been observed
that enabling mmssnoc_axi_rpm_clk with rpmcc results in an implicit
access to mmss and will crash the system if gcc_mmss_noc_cfg_ahb_clk is
disabled.

Signed-off-by: Jeffrey Hugo <[email protected]>
---
drivers/clk/qcom/gcc-msm8998.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/clk/qcom/gcc-msm8998.c b/drivers/clk/qcom/gcc-msm8998.c
index 4b75a09..b371308 100644
--- a/drivers/clk/qcom/gcc-msm8998.c
+++ b/drivers/clk/qcom/gcc-msm8998.c
@@ -2014,6 +2014,7 @@ enum {
.hw.init = &(struct clk_init_data){
.name = "gcc_mmss_noc_cfg_ahb_clk",
.ops = &clk_branch2_ops,
+ .flags = CLK_IGNORE_UNUSED,
},
},
};
--
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2018-12-13 19:37:35

by Stephen Boyd

Subject: Re: [PATCH] clk: qcom: Leave mmss noc on for 8998

Quoting Jeffrey Hugo (2018-12-13 08:59:30)
> Similar to other qcom targets, gcc_mmss_noc_cfg_ahb_clk should not be
> disabled. Any mmss access depends on this clock, and its been observed
> that enabling mmssnoc_axi_rpm_clk with rpmcc results in an implicit
> access to mmss and will crash the system if gcc_mmss_noc_cfg_ahb_clk is
> disabled.
>
> Signed-off-by: Jeffrey Hugo <[email protected]>
> ---
> drivers/clk/qcom/gcc-msm8998.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/drivers/clk/qcom/gcc-msm8998.c b/drivers/clk/qcom/gcc-msm8998.c
> index 4b75a09..b371308 100644
> --- a/drivers/clk/qcom/gcc-msm8998.c
> +++ b/drivers/clk/qcom/gcc-msm8998.c
> @@ -2014,6 +2014,7 @@ enum {
> .hw.init = &(struct clk_init_data){
> .name = "gcc_mmss_noc_cfg_ahb_clk",
> .ops = &clk_branch2_ops,
> + .flags = CLK_IGNORE_UNUSED,

It should be marked as CLK_IS_CRITICAL and a comment should be added to
the code indicating why it's critical.