Commit a8662ead authored by Martin Blumenstingl's avatar Martin Blumenstingl Committed by Neil Armstrong

clk: meson: meson8b: fix the width of the cpu_scale_div clock

According to the public S805 datasheet HHI_SYS_CPU_CLK_CNTL1[29:20] is
the register for the CPU scale_div clock. This matches the code in
Amlogic's 3.10 GPL kernel sources:
N = (aml_read_reg32(P_HHI_SYS_CPU_CLK_CNTL1) >> 20) & 0x3FF;

This means that the divider register is 10 bit wide instead of 9 bits.
So far this is not a problem since all u-boot versions I have seen are
not using the cpu_scale_div clock at all (instead they are configuring
the CPU clock to run off cpu_in_sel directly).

The fixes tag points to the latest rework of the CPU clocks. However,
even before the rework it was wrong. Commit 7a29a869 ("clk: meson:
Add support for Meson clock controller") defines MESON_N_WIDTH as 9 (in
drivers/clk/meson/clk-cpu.c). But since the old clk-cpu implementation
this only carries the fixes tag for the CPU clock rewordk.

Fixes: 251b6fd3 ("clk: meson: rework meson8b cpu clock")
Signed-off-by: default avatarMartin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: default avatarNeil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20180927085921.24627-3-martin.blumenstingl@googlemail.com
parent ad9b2b8e
......@@ -595,7 +595,7 @@ static struct clk_regmap meson8b_cpu_scale_div = {
.data = &(struct clk_regmap_div_data){
.offset = HHI_SYS_CPU_CLK_CNTL1,
.shift = 20,
.width = 9,
.width = 10,
.table = cpu_scale_table,
.flags = CLK_DIVIDER_ALLOW_ZERO,
},
......
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