[PATCH v2 6/6] PM / devfreq: Add a driver for the sun8i/sun50i MBUS
Chanwoo Choi
cw00.choi at samsung.com
Fri Oct 15 01:28:45 PDT 2021
Hi Samuel,
On 10/4/21 10:27 AM, Samuel Holland wrote:
> This driver works by adjusting the divider on the DRAM controller's
> module clock. Thus there is no fixed set of OPPs, only "full speed" down
> to "quarter speed" (or whatever the maximum divider is on that variant).
>
> It makes use of the MDFS hardware in the MBUS, in "DFS" mode, which
> takes care of updating registers during the critical section while DRAM
> is inaccessible.
>
> This driver should support several sunxi SoCs, starting with the A33,
> which have a DesignWare DDR3 controller with merged PHY register space
> and the matching MBUS register layout (so not A63 or later). However,
> the driver has only been tested on the A64/H5, so those are the only
> compatibles enabled for now.
>
> Signed-off-by: Samuel Holland <samuel at sholland.org>
> ---
> drivers/devfreq/Kconfig | 8 +
> drivers/devfreq/Makefile | 1 +
> drivers/devfreq/sun8i-a33-mbus.c | 511 +++++++++++++++++++++++++++++++
> 3 files changed, 520 insertions(+)
> create mode 100644 drivers/devfreq/sun8i-a33-mbus.c
(snip)
Looks good to me.
Acked-by: Chanwoo Choi <cw00.choi at samsung.com>
--
Best Regards,
Chanwoo Choi
Samsung Electronics
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