Commit c45ae598fc16 ("clk: qcom: support for alpha mode configuration")
added support for configuring alpha mode, but it seems that the feature
was never working in practice.
The value of the alpha_{en,mode}_mask members of the configuration gets
added to the value parameter passed to the regmap_update_bits() function,
however the same values are not getting applied to the bitmask. As the
result, the respective bits in the USER_CTL register are never modifed
which leads to improper configuration of several PLLs.
The following table shows the PLL configurations where the 'alpha_en_mask'
member is set and which are passed as a parameter for the
clk_alpha_pll_configure() function. In the table the 'expected rate' column
shows the rate the PLL should run at with the given configuration, and
the 'real rate' column shows the rate the PLL runs at actually. The real
rates has been verified on hardwareOn IPQ* platforms, on other platforms,
those are computed values only.
file pll expected rate real rate
dispcc-qcm2290.c disp_cc_pll0 768.0 MHz 768.0 MHz
dispcc-sm6115.c disp_cc_pll0 768.0 MHz 768.0 MHz
gcc-ipq5018.c ubi32_pll 1000.0 MHz != 984.0 MHz
gcc-ipq6018.c nss_crypto_pll 1200.0 MHz 1200.0 MHz
gcc-ipq6018.c ubi32_pll 1497.6 MHz != 1488.0 MHz
gcc-ipq8074.c nss_crypto_pll 1200.0 MHz != 1190.4 MHz
gcc-qcm2290.c gpll11 532.0 MHz != 518.4 MHz
gcc-qcm2290.c gpll8 533.2 MHz != 518.4 MHz
gcc-qcs404.c gpll3 921.6 MHz 921.6 MHz
gcc-sm6115.c gpll11 600.0 MHz != 595.2 MHz
gcc-sm6115.c gpll8 800.0 MHz != 787.2 MHz
gpucc-sdm660.c gpu_cc_pll0 800.0 MHz != 787.2 MHz
gpucc-sdm660.c gpu_cc_pll1 740.0 MHz != 729.6 MHz
gpucc-sm6115.c gpu_cc_pll0 1200.0 MHz != 1190.4 MHz
gpucc-sm6115.c gpu_cc_pll1 640.0 MHz != 633.6 MHz
gpucc-sm6125.c gpu_pll0 1020.0 MHz != 1017.6 MHz
gpucc-sm6125.c gpu_pll1 930.0 MHz != 921.6 MHz
mmcc-sdm660.c mmpll8 930.0 MHz != 921.6 MHz
mmcc-sdm660.c mmpll5 825.0 MHz != 806.4 MHz
As it can be seen from the above, there are several PLLs which are
configured incorrectly.
Change the code to apply both 'alpha_en_mask' and 'alpha_mode_mask'
values to the bitmask in order to configure the alpha mode correctly.
Applying the 'alpha_en_mask' fixes the initial rate of the PLLs showed
in the table above. Since the 'alpha_mode_mask' is not used by any driver
currently, that part of the change causes no functional changes.
Cc: stable@xxxxxxxxxxxxxxx
Fixes: c45ae598fc16 ("clk: qcom: support for alpha mode configuration")
Signed-off-by: Gabor Juhos <j4g8y7@xxxxxxxxx>
---
drivers/clk/qcom/clk-alpha-pll.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/clk/qcom/clk-alpha-pll.c b/drivers/clk/qcom/clk-alpha-pll.c
index f9105443d7dbb104e3cb091e59f43df25999f8b3..03cc7aa092480bfdd9eaa986d44f0545944b3b89 100644
--- a/drivers/clk/qcom/clk-alpha-pll.c
+++ b/drivers/clk/qcom/clk-alpha-pll.c
@@ -421,6 +421,8 @@ void clk_alpha_pll_configure(struct clk_alpha_pll *pll, struct regmap *regmap,
mask |= config->pre_div_mask;
mask |= config->post_div_mask;
mask |= config->vco_mask;
+ mask |= config->alpha_en_mask;
+ mask |= config->alpha_mode_mask;
regmap_update_bits(regmap, PLL_USER_CTL(pll), mask, val);
---
base-commit: 9852d85ec9d492ebef56dc5f229416c925758edc
change-id: 20241021-fix-alpha-mode-config-8383238a4854
Best regards,
--
Gabor Juhos <j4g8y7@xxxxxxxxx>
