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Subject[PATCH 4.19 056/313] clk: meson: meson8b: fix the width of the cpu_scale_div clock
Date
4.19-stable review patch.  If anyone has any objections, please let me know.

------------------

[ Upstream commit a8662eadd1032018f31e37deda811790b2326662 ]

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 7a29a869434e8b ("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: 251b6fd38bcb9c ("clk: meson: rework meson8b cpu clock")
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://lkml.kernel.org/r/20180927085921.24627-3-martin.blumenstingl@googlemail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/clk/meson/meson8b.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/clk/meson/meson8b.c b/drivers/clk/meson/meson8b.c
index 580a86d120e8..0da8334f2e43 100644
--- a/drivers/clk/meson/meson8b.c
+++ b/drivers/clk/meson/meson8b.c
@@ -583,7 +583,7 @@ 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,
},
--
2.19.1


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