[PATCH v2 2/2] memory: mtk-smi: mt8188: Add SMI clamp function

Friday Yang (杨阳) Friday.Yang at mediatek.com
Fri Nov 22 01:38:39 PST 2024


On Wed, 2024-11-20 at 12:49 +0100, AngeloGioacchino Del Regno wrote:
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> 
> 
> Il 20/11/24 07:36, Friday Yang ha scritto:
> > In order to avoid handling glitch signal when MTCMOS on/off, SMI
> > need
> > clamp and reset operation. Parse power reset settings for LARBs
> > which
> > need to reset. Register genpd callback for SMI LARBs and apply
> > reset
> > operations in the callback.
> > 
> > Signed-off-by: Friday Yang <friday.yang at mediatek.com>
> > ---
> >   drivers/memory/mtk-smi.c | 175
> > ++++++++++++++++++++++++++++++++++++++-
> >   1 file changed, 171 insertions(+), 4 deletions(-)
> > 
> > diff --git a/drivers/memory/mtk-smi.c b/drivers/memory/mtk-smi.c
> > index 2bc034dff691..c7119f655350 100644
> > --- a/drivers/memory/mtk-smi.c
> > +++ b/drivers/memory/mtk-smi.c
> > @@ -10,15 +10,21 @@
> >   #include <linux/err.h>
> >   #include <linux/io.h>
> >   #include <linux/iopoll.h>
> > +#include <linux/mfd/syscon.h>
> >   #include <linux/module.h>
> >   #include <linux/of.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/reset.h>
> > +#include <linux/reset-controller.h>
> >   #include <linux/soc/mediatek/mtk_sip_svc.h>
> >   #include <soc/mediatek/smi.h>
> >   #include <dt-bindings/memory/mt2701-larb-port.h>
> >   #include <dt-bindings/memory/mtk-memory-port.h>
> > +#include <dt-bindings/reset/mt8188-resets.h>
> > 
> >   /* SMI COMMON */
> >   #define SMI_L1LEN                   0x100
> > @@ -36,6 +42,13 @@
> >   #define SMI_DCM                             0x300
> >   #define SMI_DUMMY                   0x444
> > 
> > +#define SMI_COMMON_CLAMP_EN          0x3c0
> > +#define SMI_COMMON_CLAMP_EN_SET              0x3c4
> > +#define SMI_COMMON_CLAMP_EN_CLR              0x3c8
> > +#define SMI_COMMON_CLAMP_MASK(inport)        BIT(inport)
> > +
> > +#define SMI_SUB_COMM_INPORT_NR               (8)
> > +
> >   /* SMI LARB */
> >   #define SMI_LARB_SLP_CON                0xc
> >   #define SLP_PROT_EN                     BIT(0)
> > @@ -134,6 +147,7 @@ struct mtk_smi_larb_gen {
> >       unsigned int                    larb_direct_to_common_mask;
> >       unsigned int                    flags_general;
> >       const
> > u8                        (*ostd)[SMI_LARB_PORT_NR_MAX];
> > +     const u8                        *clamp_port;
> >   };
> > 
> >   struct mtk_smi {
> > @@ -150,6 +164,7 @@ struct mtk_smi {
> >   };
> > 
> >   struct mtk_smi_larb { /* larb: local arbiter */
> > +     struct device                   *dev;
> >       struct mtk_smi                  smi;
> >       void __iomem                    *base;
> >       struct device                   *smi_common_dev; /* common or
> > sub-common dev */
> > @@ -157,6 +172,10 @@ struct mtk_smi_larb { /* larb: local arbiter
> > */
> >       int                             larbid;
> >       u32                             *mmu;
> >       unsigned char                   *bank;
> > +     struct regmap                   *sub_comm_syscon;
> > +     u8                              sub_comm_inport;
> > +     struct notifier_block           nb;
> > +     struct reset_control            *rst_con;
> >   };
> > 
> >   static int
> > @@ -377,6 +396,19 @@ static const u8
> > mtk_smi_larb_mt8195_ostd[][SMI_LARB_PORT_NR_MAX] = {
> >       [28] = {0x1a, 0x0e, 0x0a, 0x0a, 0x0c, 0x0e, 0x10,},
> >   };
> > 
> > +static const u8 mtk_smi_larb_clamp_port_mt8188[] = {
> 
> You can just set these to BIT(x) directly, like:
> 
>         [MT8188_SMI_RST_LARB10] = BIT(0),
> 
> so that you can check if there's actually a supported/valid clamp
> port in function
> mtk_smi_larb_parse_clamp_info() - check below for comments in that
> function.
> 
> Note that you are declaring SMI_SUB_COMM_INPORT_NR = 8 and this means
> that there
> are a maximum of 8 ports, with each port having its own BIT, starting
> from BIT 0
> and ending at BIT 7 (so [7:0]).
> 
> This means that we have a maximum of 8 bits here, so even if you
> assign BIT(x) it
> all still fits in a u8! :-)

Thanks for your comments, I will modify the definition for
mtk_smi_larb_clamp_port_mt8188, and macro 'SMI_COMMON_CLAMP_MASK'
could be removed.

> 
> > +     [MT8188_SMI_RST_LARB10]         = 1,
> > +     [MT8188_SMI_RST_LARB11A]        = 2,
> > +     [MT8188_SMI_RST_LARB11C]        = 3,
> > +     [MT8188_SMI_RST_LARB12]         = 0,
> > +     [MT8188_SMI_RST_LARB11B]        = 2,
> > +     [MT8188_SMI_RST_LARB15]         = 1,
> > +     [MT8188_SMI_RST_LARB16B]        = 2,
> > +     [MT8188_SMI_RST_LARB17B]        = 3,
> > +     [MT8188_SMI_RST_LARB16A]        = 2,
> > +     [MT8188_SMI_RST_LARB17A]        = 3,
> > +};
> > +
> >   static const struct mtk_smi_larb_gen mtk_smi_larb_mt2701 = {
> >       .port_in_larb = {
> >               LARB0_PORT_OFFSET, LARB1_PORT_OFFSET,
> > @@ -423,6 +455,7 @@ static const struct mtk_smi_larb_gen
> > mtk_smi_larb_mt8188 = {
> >       .flags_general              = MTK_SMI_FLAG_THRT_UPDATE |
> > MTK_SMI_FLAG_SW_FLAG |
> >                                     MTK_SMI_FLAG_SLEEP_CTL |
> > MTK_SMI_FLAG_CFG_PORT_SEC_CTL,
> >       .ostd                       = mtk_smi_larb_mt8188_ostd,
> > +     .clamp_port                 = mtk_smi_larb_clamp_port_mt8188,
> >   };
> > 
> >   static const struct mtk_smi_larb_gen mtk_smi_larb_mt8192 = {
> > @@ -472,6 +505,60 @@ static void
> > mtk_smi_larb_sleep_ctrl_disable(struct mtk_smi_larb *larb)
> >       writel_relaxed(0, larb->base + SMI_LARB_SLP_CON);
> >   }
> > 
> > +static int mtk_smi_larb_clamp_protect_enable(struct device *dev)
> > +{
> > +     struct mtk_smi_larb *larb = dev_get_drvdata(dev);
> > +     int ret;
> > +
> > +     /* sub_comm_syscon could be NULL if larb directly linked to
> > SMI common */
> > +     if (!larb->sub_comm_syscon)
> > +             return -EINVAL;
> > +
> > +     ret = regmap_write(larb->sub_comm_syscon,
> > SMI_COMMON_CLAMP_EN_SET,
> > +                        SMI_COMMON_CLAMP_MASK(larb-
> > >sub_comm_inport));
> > +     if (ret)
> > +             dev_err(dev, "Unable to enable clamp, inport %d, ret
> > %d\n",
> > +                     larb->sub_comm_inport, ret);
> > +
> > +     return ret;
> > +}
> > +
> > +static int mtk_smi_larb_clamp_protect_disble(struct device *dev)
> 
> typo: mtk_smi_larb_clamp_protect_disable
> 
> > +{
> > +     struct mtk_smi_larb *larb = dev_get_drvdata(dev);
> > +     int ret;
> > +
> > +     /* sub_comm_syscon could be NULL if larb directly linked to
> > SMI common */
> > +     if (!larb->sub_comm_syscon)
> > +             return -EINVAL;
> > +
> > +     ret = regmap_write(larb->sub_comm_syscon,
> > SMI_COMMON_CLAMP_EN_CLR,
> > +                        SMI_COMMON_CLAMP_MASK(larb-
> > >sub_comm_inport));
> > +     if (ret)
> > +             dev_err(dev, "Unable to disable clamp, inport %d, ret
> > %d\n",
> > +                     larb->sub_comm_inport, ret);
> > +
> > +     return ret;
> > +}
> 
> ...but anyway, I would rather do it like that:
> 
> static int mtk_smi_larb_clamp_protect_enable(struct device *dev, bool
> enable)
> {
>         struct mtk_smi_larb *larb = dev_get_drvdata(dev);
>         u32 reg;
>         int ret;
> 
>         /* sub_comm_syscon could be NULL if larb directly linked to
> SMI common */
>         if (!larb->sub_comm_syscon)
>                 return -EINVAL;
> 
>         reg = enable ? SMI_COMMON_CLAMP_EN_SET :
> SMI_COMMON_CLAMP_EN_CLR;
> 
>         ret = regmap_write(larb->sub_comm_syscon, reg,
>                            SMI_COMMON_CLAMP_MASK(larb-
> >sub_comm_inport));
>         if (ret) {
>                 dev_err(dev, "Unable to %s clamp for input port %d:
> %d\n",
>                         enable ? "enable" : "disable",
>                         larb->sub_comm_inport, ret);
>                 return ret;
>         }
> 
>         return 0;
> }
> 
> ...and then call it like
> ret = mtk_smi_larb_clamp_protect_enable(dev, true);
> 
> or
> 
> ret = mtk_smi_larb_clamp_protect_enable(dev, false);
> 

Thanks for your comments, I will merge these two functions
into one. This looks better.

> > +
> > +static int mtk_smi_genpd_callback(struct notifier_block *nb,
> > +                               unsigned long flags, void *data)
> > +{
> > +     struct mtk_smi_larb *larb = container_of(nb, struct
> > mtk_smi_larb, nb);
> > +     struct device *dev = larb->dev;
> > +
> > +     if (flags == GENPD_NOTIFY_PRE_ON || flags ==
> > GENPD_NOTIFY_PRE_OFF) {
> > +             /* disable related SMI sub-common port */
> > +             mtk_smi_larb_clamp_protect_enable(dev);
> > +     } else if (flags == GENPD_NOTIFY_ON) {
> > +             /* enable related SMI sub-common port */
> > +             reset_control_reset(larb->rst_con);
> > +             mtk_smi_larb_clamp_protect_disble(dev);
> > +     }
> > +
> > +     return NOTIFY_OK;
> > +}
> > +
> >   static int mtk_smi_device_link_common(struct device *dev, struct
> > device **com_dev)
> >   {
> >       struct platform_device *smi_com_pdev;
> > @@ -528,6 +615,66 @@ static int mtk_smi_dts_clk_init(struct device
> > *dev, struct mtk_smi *smi,
> >       return ret;
> >   }
> > 
> > +static int mtk_smi_larb_parse_clamp_info(struct mtk_smi_larb
> > *larb)
> > +{
> > +     struct device *dev = larb->dev;
> > +     const struct mtk_smi_larb_gen *larb_gen = larb->larb_gen;
> > +     struct device_node *smi_node;
> > +     struct of_phandle_args args;
> > +     int ret, index;
> > +
> > +     /* Only SMI LARBs located in camera and image subsys need to
> > +      * apply clamp and reset operation, others can be skipped.
> > +      */
> > +     ret = of_parse_phandle_with_fixed_args(dev->of_node,
> > +                                            "resets", 1, 0,
> > &args);
> > +     if (ret)
> > +             return 0;
> > +
> > +     smi_node = of_parse_phandle(dev->of_node, "mediatek,smi", 0);
> > +     if (!smi_node)
> > +             return -EINVAL;
> > +
> > +     index = args.args[0];
> > +     larb->sub_comm_inport = larb_gen->clamp_port[index];
> > +     larb->sub_comm_syscon = device_node_to_regmap(smi_node);
> > +     of_node_put(smi_node);
> 
> If you declare BIT(x) as clamp_ports, or if your clamp_ports start
> from 1,
> anything that is not more than 0 is something that was not declared,
> and
> this means that you can then error check:
> 
> if (!larb->sub_comm_inport)
>         return dev_err_probe(dev, -EINVAL, "Unknown clamp port for
> larb %d\n", index);
> 

Yes, you are right. I will fix it as this way.

> > +
> > +     if (IS_ERR(larb->sub_comm_syscon) ||
> > +         larb->sub_comm_inport >= SMI_SUB_COMM_INPORT_NR) {
> > +             larb->sub_comm_syscon = NULL;
> > +             return -EINVAL;
> > +     }
> > +
> > +     return 0;
> > +}
> > +
> > +static int mtk_smi_larb_parse_reset_info(struct mtk_smi_larb
> > *larb)
> > +{
> > +     struct device *dev = larb->dev;
> > +     int ret;
> > +
> > +     /* Only SMI LARBs located in camera and image subsys need to
> > +      * apply clamp and reset operation, others can be skipped.
> > +      */
> > +     if (!of_find_property(dev->of_node, "resets", NULL))
> > +             return 0;
> 
> You don't have to manually check whether 'resets' exists or not -
> that's already
> done (devm_)reset_control_get in a way, as that will return -ENOENT
> if there is
> no 'reset-names' property. Check the comments down there....
> 
> > +
> > +     larb->rst_con = devm_reset_control_get(dev, "larb");
> > +     if (IS_ERR(larb->rst_con))
> > +             return dev_err_probe(dev, PTR_ERR(larb->rst_con),
> > +                                  "Can not get larb reset
> > controller\n");
> > +
> > +     larb->nb.notifier_call = mtk_smi_genpd_callback;
> > +     ret = dev_pm_genpd_add_notifier(dev, &larb->nb);
> > +     if (ret) {
> > +             dev_err(dev, "Failed to add genpd callback %d\n",
> > ret);
> > +             return -EINVAL;
> > +     }
> > +
> > +     return 0;
> > +}
> > +

OK, I will just check the return value of devm_reset_control_get
instead of parsing 'resets' here. This looks better.

> >   static int mtk_smi_larb_probe(struct platform_device *pdev)
> >   {
> >       struct mtk_smi_larb *larb;
> > @@ -538,6 +685,7 @@ static int mtk_smi_larb_probe(struct
> > platform_device *pdev)
> >       if (!larb)
> >               return -ENOMEM;
> > 
> > +     larb->dev = dev;
> >       larb->larb_gen = of_device_get_match_data(dev);
> >       larb->base = devm_platform_ioremap_resource(pdev, 0);
> >       if (IS_ERR(larb->base))
> > @@ -554,15 +702,29 @@ static int mtk_smi_larb_probe(struct
> > platform_device *pdev)
> >       if (ret < 0)
> >               return ret;
> > 
> > -     pm_runtime_enable(dev);
> 
>         ret = mtk_smi_larb_parse_reset_optional(larb);
> 
> Choose between:
> 
>         if (ret == 0) {
>                 ret = mtk_smi_larb_parse_smi_clamp(larb);
>                 if (ret) {
>                         dev_err_probe(dev, ret, "Failed to get SMI
> clamp\n");
>                         goto err_link_remove;
>                 }
>         } else if (ret != -ENOENT) {
>                 dev_err_probe(dev, ret, "Cannot get larb resets\n");
>                 goto err_link_remove;
>         } else {
>                 /*
>                  * Only SMI LARBs located in camera and image subsys
> need to apply
>                  * clamp and reset operation. For the others, resets
> are optional.
>                  */
>                 ret = 0;
>         }
> 
> and...
> 
>         if (ret && ret != -ENOENT) {
>                 dev_err_probe .....
>         } else if (ret) {
>                 /* only smi larbs .... */
>                 ret = 0;
>         } else {
>                 ret = mtk_smi_larb_parse_smi_clamp .....
>         }
> 
> whatever you like the most.

Thanks for your comments, I will check the return value as this way.

> 
> > +     /* find sub common to clamp larb for ISP software reset */
> > +     ret = mtk_smi_larb_parse_clamp_info(larb);
> > +     if (ret) {
> > +             dev_err(dev, "Failed to get clamp setting for
> > larb\n");
> > +             goto err_link_remove;
> > +     }
> > +
> > +     ret = mtk_smi_larb_parse_reset_info(larb);
> > +     if (ret) {
> > +             dev_err(dev, "Failed to get power setting for
> > larb\n");
> > +             goto err_link_remove;
> > +     }
> > +
> >       platform_set_drvdata(pdev, larb);
> >       ret = component_add(dev, &mtk_smi_larb_component_ops);
> >       if (ret)
> > -             goto err_pm_disable;
> > +             goto err_link_remove;
> > +
> > +     pm_runtime_enable(dev);
> > +
> >       return 0;
> > 
> > -err_pm_disable:
> > -     pm_runtime_disable(dev);
> > +err_link_remove:
> >       device_link_remove(dev, larb->smi_common_dev);
> >       return ret;
> >   }
> > @@ -686,6 +848,10 @@ static const struct mtk_smi_common_plat
> > mtk_smi_common_mt8188_vpp = {
> >       .init     = mtk_smi_common_mt8195_init,
> >   };
> > 
> > +static const struct mtk_smi_common_plat mtk_smi_sub_common_mt8188
> > = {
> > +     .type     = MTK_SMI_GEN2_SUB_COMM,
> 
> ...no gals in MT8188?!
> 

Yes, there is gals in MT8188 hardware design. And the 'gals' clock 
may be the same as the 'apb' and 'smi' clock.
I will add this in the next version, thanks for your comments.

> Cheers,
> Angelo
> 
> > +};
> > +
> >   static const struct mtk_smi_common_plat mtk_smi_common_mt8192 = {
> >       .type     = MTK_SMI_GEN2,
> >       .has_gals = true,
> > @@ -729,6 +895,7 @@ static const struct of_device_id
> > mtk_smi_common_of_ids[] = {
> >       {.compatible = "mediatek,mt8186-smi-common", .data =
> > &mtk_smi_common_mt8186},
> >       {.compatible = "mediatek,mt8188-smi-common-vdo", .data =
> > &mtk_smi_common_mt8188_vdo},
> >       {.compatible = "mediatek,mt8188-smi-common-vpp", .data =
> > &mtk_smi_common_mt8188_vpp},
> > +     {.compatible = "mediatek,mt8188-smi-sub-common", .data =
> > &mtk_smi_sub_common_mt8188},
> >       {.compatible = "mediatek,mt8192-smi-common", .data =
> > &mtk_smi_common_mt8192},
> >       {.compatible = "mediatek,mt8195-smi-common-vdo", .data =
> > &mtk_smi_common_mt8195_vdo},
> >       {.compatible = "mediatek,mt8195-smi-common-vpp", .data =
> > &mtk_smi_common_mt8195_vpp},
> 
> 


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