Re: [PATCH 2/2] soc: mediatek: Add MT8196 VMM driver support

["Nancy Lin (林欣螢)" <Nancy.Lin@mediatek.com>]

Hi Krzysztof,

Thanks for your review.

On Thu, 2025-05-22 at 17:10 +0200, Krzysztof Kozlowski wrote:
> 
> External email : Please do not click links or open attachments until
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> 
> 
> On 22/05/2025 17:03, Nancy.Lin wrote:
> > From: Nancy Lin <nancy.lin@mediatek.com>
> > 
> > Add a driver for the MediaTek MT8196 VMM (Vcore for MultiMedia)
> > controller, which acts as the main power supplier for multimedia
> > power
> > domains such as display, video encode, and video decode on MediaTek
> > SoCs.
> > 
> > The VMM controller provides virtual regulators for multimedia IPs
> > and
> > coordinates with the hardware common clock framework (hwccf) and
> > the
> > Video Companioin Processor (VCP) to manage power domains. The
> > driver
> > uses a hardware voter through HWCCF to notify the VCP to turn on or
> > off VMM-related bucks.
> > 
> > Signed-off-by: Nancy Lin <nancy.lin@mediatek.com>
> > ---
> >  drivers/soc/mediatek/Kconfig       |  12 +
> >  drivers/soc/mediatek/Makefile      |   1 +
> >  drivers/soc/mediatek/mtk-vmm-drv.c | 471
> > +++++++++++++++++++++++++++++
> >  3 files changed, 484 insertions(+)
> >  create mode 100644 drivers/soc/mediatek/mtk-vmm-drv.c
> > 
> > diff --git a/drivers/soc/mediatek/Kconfig
> > b/drivers/soc/mediatek/Kconfig
> > index d7293977f06e..4db4a0876083 100644
> > --- a/drivers/soc/mediatek/Kconfig
> > +++ b/drivers/soc/mediatek/Kconfig
> > @@ -69,6 +69,18 @@ config MTK_MMSYS
> >         Say yes here to add support for the MediaTek Multimedia
> >         Subsystem (MMSYS).
> > 
> > +config MTK_VMM
> > +     tristate "MediaTek VMM driver"
> > +     help
> > +       Say Y here to enable support for the MediaTek VMM (Vcore
> > for
> > +       MultiMedia) controller, which acts as the main power
> > supplier
> > +       for multimedia power domains such as display, video encode
> > and
> > +       decode on MediaTek SoCs. The VMM controller provides
> > virtual
> > +       regulators for multimedia IPs and coordinates with the
> > hardware
> > +       common clock framework (hwccf) and the Video Companion
> > Processor
> > +       (VCP) to manage power domains. The VMM driver uses hardware
> > voter
> > +       through hwccf to notify VCP to turn on/off VMM-related
> > bucks.
> > +
> >  config MTK_SVS
> >       tristate "MediaTek Smart Voltage Scaling(SVS)"
> >       depends on NVMEM_MTK_EFUSE && NVMEM
> > diff --git a/drivers/soc/mediatek/Makefile
> > b/drivers/soc/mediatek/Makefile
> > index 0665573e3c4b..2b2071614ac4 100644
> > --- a/drivers/soc/mediatek/Makefile
> > +++ b/drivers/soc/mediatek/Makefile
> > @@ -6,6 +6,7 @@ obj-$(CONFIG_MTK_INFRACFG) += mtk-infracfg.o
> >  obj-$(CONFIG_MTK_PMIC_WRAP) += mtk-pmic-wrap.o
> >  obj-$(CONFIG_MTK_REGULATOR_COUPLER) += mtk-regulator-coupler.o
> >  obj-$(CONFIG_MTK_MMSYS) += mtk-mmsys.o
> > +obj-$(CONFIG_MTK_VMM) += mtk-vmm-drv.o
> >  obj-$(CONFIG_MTK_MMSYS) += mtk-mutex.o
> >  obj-$(CONFIG_MTK_SVS) += mtk-svs.o
> >  obj-$(CONFIG_MTK_SOCINFO) += mtk-socinfo.o
> > diff --git a/drivers/soc/mediatek/mtk-vmm-drv.c
> > b/drivers/soc/mediatek/mtk-vmm-drv.c
> > new file mode 100644
> > index 000000000000..de4ceb7d59fa
> > --- /dev/null
> > +++ b/drivers/soc/mediatek/mtk-vmm-drv.c
> > @@ -0,0 +1,471 @@
> > +// SPDX-License-Identifier: (GPL-2.0 OR MIT)
> > +/*
> > + * Copyright (c) 2025 MediaTek Inc.
> > + * Author: Yunfei Dong <yunfei.dong@mediatek.com>
> > + */
> > +
> > +#include <linux/clk.h>
> > +#include <linux/delay.h>
> > +#include <linux/device.h>
> > +#include <linux/kthread.h>
> > +#include <linux/mfd/syscon.h>
> > +#include <linux/module.h>
> > +#include <linux/of_platform.h>
> > +#include <linux/platform_device.h>
> > +#include <linux/pm_domain.h>
> > +#include <linux/pm_runtime.h>
> > +#include <linux/regmap.h>
> > +#include <linux/regulator/driver.h>
> > +#if IS_ENABLED(CONFIG_MTK_VCP_RPROC)
> 
> And that's the proof you send some sort of downstream code.
> 
> This does not exist.
> 
Sorry, I forgot add reference patch. This patch is based on [1].

[1] Add vcp driver
https://patchwork.kernel.org/project/linux-mediatek/list/?series=949232



> > +#include <linux/remoteproc.h>
> > +#include <linux/remoteproc/mtk_vcp_public.h>
> > +#endif
> > +
> > +#define mtk_vmm_dbg(dev, fmt, args...) \
> > +     dev_dbg(dev, "[vmm] %s(%d): " fmt "\n", __func__, __LINE__,
> > ##args)
> 
> No, you do not get your own debug code.
> 
> NAK.
> 
> This is nowhere close to upstream code. Don't send us downstream
> patterns please.
> 
OK, I will remove own debug code and refine it. Thanks!

Best regards,
Nancy


> Best regards,
> Krzysztof