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author | Roman Stratiienko <r.stratiienko@gmail.com> | 2022-07-05 10:52:26 +0300 |
---|---|---|
committer | Jernej Skrabec <jernej.skrabec@gmail.com> | 2022-07-08 18:13:50 +0200 |
commit | 4167ac8a657e4f0860419adf24d4b91a26580488 (patch) | |
tree | 2d2be2a4b98da10728e1cb13947de7ff5449ed9f /lib | |
parent | b17403a56064c63b10dc56884b99114355f03e57 (diff) |
clk: sunxi-ng: sun50i: h6: Modify GPU clock configuration to support DFS
Using simple bash script it was discovered that not all CCU registers
can be safely used for DFS, e.g.:
while true
do
devmem 0x3001030 4 0xb0003e02
devmem 0x3001030 4 0xb0001e02
done
Script above changes the GPU_PLL multiplier register value. While the
script is running, the user should interact with the user interface.
Using this method the following results were obtained:
| Register | Name | Bits | Values | Result |
| -- | -- | -- | -- | -- |
| 0x3001030 | GPU_PLL.MULT | 15..8 | 20-62 | OK |
| 0x3001030 | GPU_PLL.INDIV | 1 | 0-1 | OK |
| 0x3001030 | GPU_PLL.OUTDIV | 0 | 0-1 | FAIL |
| 0x3001670 | GPU_CLK.DIV | 3..0 | ANY | FAIL |
DVFS started to work seamlessly once dividers which caused the
glitches were set to fixed values.
Signed-off-by: Roman Stratiienko <r.stratiienko@gmail.com>
Reviewed-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Signed-off-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Link: https://lore.kernel.org/r/20220705075226.359475-1-r.stratiienko@gmail.com
Diffstat (limited to 'lib')
0 files changed, 0 insertions, 0 deletions