On 22/10/2024 10:45, Gabor Juhos wrote:
The comment before the config of the GPLL3 PLL says that the PLL should run at 930 MHz. In contrary to this, calculating the frequency from the current configuration values by using 19.2 MHz as input frequency defined in 'qcs404.dtsi', it gives 921.6 MHz: $ xo=19200000; l=48; alpha=0x0; alpha_hi=0x0 $ echo "$xo * ($((l)) + $(((alpha_hi << 32 | alpha) >> 8)) / 2^32)" | bc -l 921600000.00000000000000000000 Set 'alpha_hi' in the configuration to a value used in downstream kernels [1][2] in order to get the correct output rate: $ xo=19200000; l=48; alpha=0x0; alpha_hi=0x70 $ echo "$xo * ($((l)) + $(((alpha_hi << 32 | alpha) >> 8)) / 2^32)" | bc -l 930000000.00000000000000000000 The change is based on static code analysis, compile tested only. [1] https://git.codelinaro.org/clo/la/kernel/msm-5.4/-/blob/kernel.lnx.5.4.r56-rel/drivers/clk/qcom/gcc-qcs404.c?ref_type=heads#L335 [2} https://git.codelinaro.org/clo/la/kernel/msm-5.15/-/blob/kernel.lnx.5.15.r49-rel/drivers/clk/qcom/gcc-qcs404.c?ref_type=heads#L127 Cc: stable@xxxxxxxxxxxxxxx Fixes: 652f1813c113 ("clk: qcom: gcc: Add global clock controller driver for QCS404") Signed-off-by: Gabor Juhos <j4g8y7@xxxxxxxxx>
It should be possible to test / verify this change with debugcc on qcs404 https://github.com/linux-msm/debugcc/blob/master/qcs404.c --- bod