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References: <20211207015446.1250854-1-aford173@gmail.com> <20211207015446.1250854-6-aford173@gmail.com>
 <Ya9V7Kwa8MICeS34@eze-laptop>
In-Reply-To: <Ya9V7Kwa8MICeS34@eze-laptop>
From:   Adam Ford <aford173@gmail.com>
Date:   Tue, 7 Dec 2021 07:24:11 -0600
Message-ID: <CAHCN7xJ9kTdTmhbSwwNCCivRdTULO494CEj0eVkfPfqbPqNPvA@mail.gmail.com>
Subject: Re: [RFC V2 5/6] media: hantro: split i.MX8MQ G1 and G2 code
To:     Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Cc:     linux-media <linux-media@vger.kernel.org>,
        Chris Healy <cphealy@gmail.com>,
        Benjamin Gaignard <benjamin.gaignard@collabora.com>,
        Hans Verkuil <hverkuil@xs4all.nl>,
        Philipp Zabel <p.zabel@pengutronix.de>,
        Mauro Carvalho Chehab <mchehab@kernel.org>,
        Rob Herring <robh+dt@kernel.org>,
        Shawn Guo <shawnguo@kernel.org>,
        Sascha Hauer <s.hauer@pengutronix.de>,
        Pengutronix Kernel Team <kernel@pengutronix.de>,
        Fabio Estevam <festevam@gmail.com>,
        NXP Linux Team <linux-imx@nxp.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Lucas Stach <l.stach@pengutronix.de>,
        "open list:HANTRO VPU CODEC DRIVER" 
        <linux-rockchip@lists.infradead.org>,
        devicetree <devicetree@vger.kernel.org>,
        arm-soc <linux-arm-kernel@lists.infradead.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        "open list:STAGING SUBSYSTEM" <linux-staging@lists.linux.dev>
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On Tue, Dec 7, 2021 at 6:39 AM Ezequiel Garcia
<ezequiel@vanguardiasur.com.ar> wrote:
>
> Hi Adam,
>
> Thanks for the good work! This is looking quite promising.
>
> On Mon, Dec 06, 2021 at 07:54:44PM -0600, Adam Ford wrote:
> > The VPU in the i.MX8MQ is really the combination of Hantro G1 and
> > Hantro G2. With the updated vpu-blk-ctrl, the power domains system
> > can enable and disable them separately as well as pull them out of
> > reset. This simplifies the code and lets them run independently.
> >
> > Signed-off-by: Adam Ford <aford173@gmail.com>
> >
> > diff --git a/drivers/staging/media/hantro/hantro_drv.c b/drivers/staging/media/hantro/hantro_drv.c
> > index ab2467998d29..d803252a5aba 100644
> > --- a/drivers/staging/media/hantro/hantro_drv.c
> > +++ b/drivers/staging/media/hantro/hantro_drv.c
> > @@ -608,8 +608,8 @@ static const struct of_device_id of_hantro_match[] = {
> >       { .compatible = "rockchip,rk3399-vpu", .data = &rk3399_vpu_variant, },
> >  #endif
> >  #ifdef CONFIG_VIDEO_HANTRO_IMX8M
> > -     { .compatible = "nxp,imx8mq-vpu", .data = &imx8mq_vpu_variant, },
> > -     { .compatible = "nxp,imx8mq-vpu-g2", .data = &imx8mq_vpu_g2_variant },
> > +     { .compatible = "nxp,imx8mq-vpu-g1", .data = &imx8mq_vpu_g1_variant, },
>
> I think it's important to clarify that you are breaking support
> for the previous device-tree binding. Not only because of the compatible
> string change, but because the binding is now quite different.
>
> Note that in the past Benjamin tried to avoid this.
> IIRC, his proposal was backwards compatible.

I was looking at how to do this, but the stand-alone vpu bindings did
the reset and the fuses manually, it causes issues.  When the block
control is enabled those memory locations for the resets and fuses are
assigned to the blk-ctrl driver, so attempting to access them from a
different driver was a violation.

When I started looking at this, the stand-alone VPU was trying to be
both G1 and G2, but when I was testing it before I made changes, I
didn't see the G2 function at all. When I was done the G2 seemed to
work, so it seems like this is an improvement.  If you want me to keep
the previous compatible flag, I could rename the nxp,imx8mq-vpu-g1
back to nxp,imx8mq-vpu and remove the reset/fuse controls, but I'd
have to add the blk-ctrl reference, so it seemed to me like a better
alternative to deprecate the old binding/driver and replace it with
the new one because of the significant changes.  Since I'd like to
rebase the i.MX8M Mini I did on this work, it seemed weird to have
nxp,imx8mq-vpu, nxp,imx8mq-vpu-g2, nxp,imx8mm-vpu-g1, and
nxp,imx8mm-vpu-g2 where the only one without a Gx name was the
original 8MQ binding but limited to G1 functionality and the G2
stripped out.
>
> If this is unavoidable, due to how the blk-ctrl is handled, then that's
> fine. Given it's a staging driver, we can still play these games.
>
> Having said that, let's please make this very clear in the commit
> description, to it's clear for developers forward-porting their kernels.
> This applies not only to this commit, but to all commits that affect
> the binding.

When I post the formal patch, I will add a note that this explicitly
deprecates the old bindings due to the fact that the G1 and G2 are
separate IP blocks in the reference manual, and blk-ctrl is a
completely separate driver altogether.

>
> Thanks!
> Ezequiel
>
> > +     { .compatible = "nxp,imx8mq-vpu-g2", .data = &imx8mq_vpu_g2_variant, },
> >  #endif
> >  #ifdef CONFIG_VIDEO_HANTRO_SAMA5D4
> >       { .compatible = "microchip,sama5d4-vdec", .data = &sama5d4_vdec_variant, },
> > diff --git a/drivers/staging/media/hantro/hantro_hw.h b/drivers/staging/media/hantro/hantro_hw.h
> > index cff817ca8d22..122b83a16663 100644
> > --- a/drivers/staging/media/hantro/hantro_hw.h
> > +++ b/drivers/staging/media/hantro/hantro_hw.h
> > @@ -299,8 +299,8 @@ enum hantro_enc_fmt {
> >       ROCKCHIP_VPU_ENC_FMT_UYVY422 = 3,
> >  };
> >
> > +extern const struct hantro_variant imx8mq_vpu_g1_variant;
> >  extern const struct hantro_variant imx8mq_vpu_g2_variant;
> > -extern const struct hantro_variant imx8mq_vpu_variant;
> >  extern const struct hantro_variant px30_vpu_variant;
> >  extern const struct hantro_variant rk3036_vpu_variant;
> >  extern const struct hantro_variant rk3066_vpu_variant;
> > diff --git a/drivers/staging/media/hantro/imx8m_vpu_hw.c b/drivers/staging/media/hantro/imx8m_vpu_hw.c
> > index 1a43f6fceef9..c9f6e8472258 100644
> > --- a/drivers/staging/media/hantro/imx8m_vpu_hw.c
> > +++ b/drivers/staging/media/hantro/imx8m_vpu_hw.c
> > @@ -13,67 +13,6 @@
> >  #include "hantro_g1_regs.h"
> >  #include "hantro_g2_regs.h"
> >
> > -#define CTRL_SOFT_RESET              0x00
> > -#define RESET_G1             BIT(1)
> > -#define RESET_G2             BIT(0)
> > -
> > -#define CTRL_CLOCK_ENABLE    0x04
> > -#define CLOCK_G1             BIT(1)
> > -#define CLOCK_G2             BIT(0)
> > -
> > -#define CTRL_G1_DEC_FUSE     0x08
> > -#define CTRL_G1_PP_FUSE              0x0c
> > -#define CTRL_G2_DEC_FUSE     0x10
> > -
> > -static void imx8m_soft_reset(struct hantro_dev *vpu, u32 reset_bits)
> > -{
> > -     u32 val;
> > -
> > -     /* Assert */
> > -     val = readl(vpu->ctrl_base + CTRL_SOFT_RESET);
> > -     val &= ~reset_bits;
> > -     writel(val, vpu->ctrl_base + CTRL_SOFT_RESET);
> > -
> > -     udelay(2);
> > -
> > -     /* Release */
> > -     val = readl(vpu->ctrl_base + CTRL_SOFT_RESET);
> > -     val |= reset_bits;
> > -     writel(val, vpu->ctrl_base + CTRL_SOFT_RESET);
> > -}
> > -
> > -static void imx8m_clk_enable(struct hantro_dev *vpu, u32 clock_bits)
> > -{
> > -     u32 val;
> > -
> > -     val = readl(vpu->ctrl_base + CTRL_CLOCK_ENABLE);
> > -     val |= clock_bits;
> > -     writel(val, vpu->ctrl_base + CTRL_CLOCK_ENABLE);
> > -}
> > -
> > -static int imx8mq_runtime_resume(struct hantro_dev *vpu)
> > -{
> > -     int ret;
> > -
> > -     ret = clk_bulk_prepare_enable(vpu->variant->num_clocks, vpu->clocks);
> > -     if (ret) {
> > -             dev_err(vpu->dev, "Failed to enable clocks\n");
> > -             return ret;
> > -     }
> > -
> > -     imx8m_soft_reset(vpu, RESET_G1 | RESET_G2);
> > -     imx8m_clk_enable(vpu, CLOCK_G1 | CLOCK_G2);
> > -
> > -     /* Set values of the fuse registers */
> > -     writel(0xffffffff, vpu->ctrl_base + CTRL_G1_DEC_FUSE);
> > -     writel(0xffffffff, vpu->ctrl_base + CTRL_G1_PP_FUSE);
> > -     writel(0xffffffff, vpu->ctrl_base + CTRL_G2_DEC_FUSE);
> > -
> > -     clk_bulk_disable_unprepare(vpu->variant->num_clocks, vpu->clocks);
> > -
> > -     return 0;
> > -}
> > -
> >  /*
> >   * Supported formats.
> >   */
> > @@ -209,27 +148,6 @@ static irqreturn_t imx8m_vpu_g2_irq(int irq, void *dev_id)
> >       return IRQ_HANDLED;
> >  }
> >
> > -static int imx8mq_vpu_hw_init(struct hantro_dev *vpu)
> > -{
> > -     vpu->ctrl_base = vpu->reg_bases[vpu->variant->num_regs - 1];
> > -
> > -     return 0;
> > -}
> > -
> > -static void imx8m_vpu_g1_reset(struct hantro_ctx *ctx)
> > -{
> > -     struct hantro_dev *vpu = ctx->dev;
> > -
> > -     imx8m_soft_reset(vpu, RESET_G1);
> > -}
> > -
> > -static void imx8m_vpu_g2_reset(struct hantro_ctx *ctx)
> > -{
> > -     struct hantro_dev *vpu = ctx->dev;
> > -
> > -     imx8m_soft_reset(vpu, RESET_G2);
> > -}
> > -
> >  /*
> >   * Supported codec ops.
> >   */
> > @@ -237,19 +155,16 @@ static void imx8m_vpu_g2_reset(struct hantro_ctx *ctx)
> >  static const struct hantro_codec_ops imx8mq_vpu_codec_ops[] = {
> >       [HANTRO_MODE_MPEG2_DEC] = {
> >               .run = hantro_g1_mpeg2_dec_run,
> > -             .reset = imx8m_vpu_g1_reset,
> >               .init = hantro_mpeg2_dec_init,
> >               .exit = hantro_mpeg2_dec_exit,
> >       },
> >       [HANTRO_MODE_VP8_DEC] = {
> >               .run = hantro_g1_vp8_dec_run,
> > -             .reset = imx8m_vpu_g1_reset,
> >               .init = hantro_vp8_dec_init,
> >               .exit = hantro_vp8_dec_exit,
> >       },
> >       [HANTRO_MODE_H264_DEC] = {
> >               .run = hantro_g1_h264_dec_run,
> > -             .reset = imx8m_vpu_g1_reset,
> >               .init = hantro_h264_dec_init,
> >               .exit = hantro_h264_dec_exit,
> >       },
> > @@ -258,14 +173,12 @@ static const struct hantro_codec_ops imx8mq_vpu_codec_ops[] = {
> >  static const struct hantro_codec_ops imx8mq_vpu_g2_codec_ops[] = {
> >       [HANTRO_MODE_HEVC_DEC] = {
> >               .run = hantro_g2_hevc_dec_run,
> > -             .reset = imx8m_vpu_g2_reset,
> >               .init = hantro_hevc_dec_init,
> >               .exit = hantro_hevc_dec_exit,
> >       },
> >       [HANTRO_MODE_VP9_DEC] = {
> >               .run = hantro_g2_vp9_dec_run,
> >               .done = hantro_g2_vp9_dec_done,
> > -             .reset = imx8m_vpu_g2_reset,
> >               .init = hantro_vp9_dec_init,
> >               .exit = hantro_vp9_dec_exit,
> >       },
> > @@ -275,7 +188,7 @@ static const struct hantro_codec_ops imx8mq_vpu_g2_codec_ops[] = {
> >   * VPU variants.
> >   */
> >
> > -static const struct hantro_irq imx8mq_irqs[] = {
> > +static const struct hantro_irq imx8mq_g1_irqs[] = {
> >       { "g1", imx8m_vpu_g1_irq },
> >  };
> >
> > @@ -283,10 +196,12 @@ static const struct hantro_irq imx8mq_g2_irqs[] = {
> >       { "g2", imx8m_vpu_g2_irq },
> >  };
> >
> > -static const char * const imx8mq_clk_names[] = { "g1", "g2", "bus" };
> > -static const char * const imx8mq_reg_names[] = { "g1", "g2", "ctrl" };
> > +static const char * const imx8mq_g1_clk_names[] = { "g1" };
> > +static const char * const imx8mq_g1_reg_names[] = { "g1" };
> > +static const char * const imx8mq_g2_clk_names[] = { "g2" };
> > +static const char * const imx8mq_g2_reg_names[] = { "g2" };
> >
> > -const struct hantro_variant imx8mq_vpu_variant = {
> > +const struct hantro_variant imx8mq_vpu_g1_variant = {
> >       .dec_fmts = imx8m_vpu_dec_fmts,
> >       .num_dec_fmts = ARRAY_SIZE(imx8m_vpu_dec_fmts),
> >       .postproc_fmts = imx8m_vpu_postproc_fmts,
> > @@ -295,14 +210,12 @@ const struct hantro_variant imx8mq_vpu_variant = {
> >       .codec = HANTRO_MPEG2_DECODER | HANTRO_VP8_DECODER |
> >                HANTRO_H264_DECODER,
> >       .codec_ops = imx8mq_vpu_codec_ops,
> > -     .init = imx8mq_vpu_hw_init,
> > -     .runtime_resume = imx8mq_runtime_resume,
> > -     .irqs = imx8mq_irqs,
> > -     .num_irqs = ARRAY_SIZE(imx8mq_irqs),
> > -     .clk_names = imx8mq_clk_names,
> > -     .num_clocks = ARRAY_SIZE(imx8mq_clk_names),
> > -     .reg_names = imx8mq_reg_names,
> > -     .num_regs = ARRAY_SIZE(imx8mq_reg_names)
> > +     .irqs = imx8mq_g1_irqs,
> > +     .num_irqs = ARRAY_SIZE(imx8mq_g1_irqs),
> > +     .clk_names = imx8mq_g1_clk_names,
> > +     .num_clocks = ARRAY_SIZE(imx8mq_g1_clk_names),
> > +     .reg_names = imx8mq_g1_reg_names,
> > +     .num_regs = ARRAY_SIZE(imx8mq_g1_reg_names),
> >  };
> >
> >  const struct hantro_variant imx8mq_vpu_g2_variant = {
> > @@ -314,10 +227,10 @@ const struct hantro_variant imx8mq_vpu_g2_variant = {
> >       .postproc_ops = &hantro_g2_postproc_ops,
> >       .codec = HANTRO_HEVC_DECODER | HANTRO_VP9_DECODER,
> >       .codec_ops = imx8mq_vpu_g2_codec_ops,
> > -     .init = imx8mq_vpu_hw_init,
> > -     .runtime_resume = imx8mq_runtime_resume,
> >       .irqs = imx8mq_g2_irqs,
> >       .num_irqs = ARRAY_SIZE(imx8mq_g2_irqs),
> > -     .clk_names = imx8mq_clk_names,
> > -     .num_clocks = ARRAY_SIZE(imx8mq_clk_names),
> > +     .clk_names = imx8mq_g2_clk_names,
> > +     .num_clocks = ARRAY_SIZE(imx8mq_g2_clk_names),
> > +     .reg_names = imx8mq_g2_reg_names,
> > +     .num_regs = ARRAY_SIZE(imx8mq_g2_reg_names),
> >  };
> > --
> > 2.32.0
> >