Message-ID: <DU0PR04MB9417EABB1B0A9B550E94236288559@DU0PR04MB9417.eurprd04.prod.outlook.com>
Date:   Tue, 27 Sep 2022 02:48:02 +0000
From:   Peng Fan <peng.fan@....com>
To:     Mathieu Poirier <mathieu.poirier@...aro.org>,
        "Peng Fan (OSS)" <peng.fan@....nxp.com>
CC:     "bjorn.andersson@...nel.org" <bjorn.andersson@...nel.org>,
        "robh+dt@...nel.org" <robh+dt@...nel.org>,
        "krzysztof.kozlowski+dt@...aro.org" 
        <krzysztof.kozlowski+dt@...aro.org>,
        "shawnguo@...nel.org" <shawnguo@...nel.org>,
        "s.hauer@...gutronix.de" <s.hauer@...gutronix.de>,
        "kernel@...gutronix.de" <kernel@...gutronix.de>,
        "festevam@...il.com" <festevam@...il.com>,
        dl-linux-imx <linux-imx@....com>,
        "linux-remoteproc@...r.kernel.org" <linux-remoteproc@...r.kernel.org>,
        "devicetree@...r.kernel.org" <devicetree@...r.kernel.org>,
        "linux-arm-kernel@...ts.infradead.org" 
        <linux-arm-kernel@...ts.infradead.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: RE: [PATCH V5 3/6] remoteproc: imx_rproc: support attaching to
 i.MX8QXP M4

Hi Mathieu,

Thanks for reviewing this patchset.
> Subject: Re: [PATCH V5 3/6] remoteproc: imx_rproc: support attaching to
> i.MX8QXP M4
> 
> On Wed, Aug 24, 2022 at 09:10:20AM +0800, Peng Fan (OSS) wrote:
> > From: Peng Fan <peng.fan@....com>
> >
> > When M4 is kicked by SCFW, M4 runs in its own hardware partition,
> > Linux could only do IPC with M4, it could not start, stop, update image.
> >
> > We disable recovery reboot when M4 is managed by SCFW, because
> > remoteproc core still not support M4 auto-recovery without loading
> > image.
> >
> > Signed-off-by: Peng Fan <peng.fan@....com>
> > ---
> >  drivers/remoteproc/imx_rproc.c | 108
> > ++++++++++++++++++++++++++++++++-
> >  1 file changed, 107 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/remoteproc/imx_rproc.c
> > b/drivers/remoteproc/imx_rproc.c index 7cc4fd207e2d..bcba74e90020
> > 100644
> > --- a/drivers/remoteproc/imx_rproc.c
> > +++ b/drivers/remoteproc/imx_rproc.c
> > @@ -6,6 +6,7 @@
> >  #include <linux/arm-smccc.h>
> >  #include <linux/clk.h>
> >  #include <linux/err.h>
> > +#include <linux/firmware/imx/sci.h>
> >  #include <linux/interrupt.h>
> >  #include <linux/kernel.h>
> >  #include <linux/mailbox_client.h>
> > @@ -59,6 +60,8 @@
> >  #define IMX_SIP_RPROC_STARTED		0x01
> >  #define IMX_SIP_RPROC_STOP		0x02
> >
> > +#define IMX_SC_IRQ_GROUP_REBOOTED	5
> > +
> >  /**
> >   * struct imx_rproc_mem - slim internal memory structure
> >   * @cpu_addr: MPU virtual address of the memory region @@ -89,6
> > +92,10 @@ struct imx_rproc {
> >  	struct work_struct		rproc_work;
> >  	struct workqueue_struct		*workqueue;
> >  	void __iomem			*rsc_table;
> > +	struct imx_sc_ipc		*ipc_handle;
> > +	struct notifier_block		rproc_nb;
> > +	u32				rproc_pt;	/* partition id */
> > +	u32				rsrc_id;	/* resource id */
> >  };
> >
> >  static const struct imx_rproc_att imx_rproc_att_imx93[] = { @@ -117,6
> > +124,18 @@ static const struct imx_rproc_att imx_rproc_att_imx93[] = {
> >  	{ 0xD0000000, 0xa0000000, 0x10000000, 0 },  };
> >
> > +static const struct imx_rproc_att imx_rproc_att_imx8qxp[] = {
> > +	{ 0x08000000, 0x08000000, 0x10000000, 0 },
> > +	/* TCML/U */
> > +	{ 0x1FFE0000, 0x34FE0000, 0x00040000, ATT_OWN | ATT_IOMEM },
> > +	/* OCRAM(Low 96KB) */
> > +	{ 0x21000000, 0x00100000, 0x00018000, 0 },
> > +	/* OCRAM */
> > +	{ 0x21100000, 0x00100000, 0x00040000, 0 },
> > +	/* DDR (Data) */
> > +	{ 0x80000000, 0x80000000, 0x60000000, 0 }, };
> > +
> >  static const struct imx_rproc_att imx_rproc_att_imx8mn[] = {
> >  	/* dev addr , sys addr  , size	    , flags */
> >  	/* ITCM   */
> > @@ -255,6 +274,12 @@ static const struct imx_rproc_dcfg
> imx_rproc_cfg_imx8mq = {
> >  	.method		= IMX_RPROC_MMIO,
> >  };
> >
> > +static const struct imx_rproc_dcfg imx_rproc_cfg_imx8qxp = {
> > +	.att		= imx_rproc_att_imx8qxp,
> > +	.att_size	= ARRAY_SIZE(imx_rproc_att_imx8qxp),
> > +	.method		= IMX_RPROC_SCU_API,
> > +};
> > +
> >  static const struct imx_rproc_dcfg imx_rproc_cfg_imx8ulp = {
> >  	.att		= imx_rproc_att_imx8ulp,
> >  	.att_size	= ARRAY_SIZE(imx_rproc_att_imx8ulp),
> > @@ -680,6 +705,37 @@ static void imx_rproc_free_mbox(struct rproc
> *rproc)
> >  	mbox_free_channel(priv->rx_ch);
> >  }
> >
> > +static void imx_rproc_put_scu(struct rproc *rproc) {
> > +	struct imx_rproc *priv = rproc->priv;
> > +	const struct imx_rproc_dcfg *dcfg = priv->dcfg;
> > +
> > +	if (dcfg->method != IMX_RPROC_SCU_API)
> > +		return;
> > +
> > +	if (!imx_sc_rm_is_resource_owned(priv->ipc_handle, priv->rsrc_id))
> > +		return;
> > +
> > +	imx_scu_irq_group_enable(IMX_SC_IRQ_GROUP_REBOOTED,
> BIT(priv->rproc_pt), false);
> > +	imx_scu_irq_unregister_notifier(&priv->rproc_nb);
> > +}
> > +
> > +static int imx_rproc_partition_notify(struct notifier_block *nb,
> > +				      unsigned long event, void *group) {
> > +	struct imx_rproc *priv = container_of(nb, struct imx_rproc,
> > +rproc_nb);
> > +
> > +	/* Ignore other irqs */
> > +	if (!((event & BIT(priv->rproc_pt)) && (*(u8 *)group ==
> IMX_SC_IRQ_GROUP_REBOOTED)))
> > +		return 0;
> > +
> > +	rproc_report_crash(priv->rproc, RPROC_WATCHDOG);
> > +
> > +	pr_info("Partition%d reset!\n", priv->rproc_pt);
> > +
> > +	return 0;
> > +}
> > +
> >  static int imx_rproc_detect_mode(struct imx_rproc *priv)  {
> >  	struct regmap_config config = { .name = "imx-rproc" }; @@ -689,6
> > +745,7 @@ static int imx_rproc_detect_mode(struct imx_rproc *priv)
> >  	struct arm_smccc_res res;
> >  	int ret;
> >  	u32 val;
> > +	u8 pt;
> >
> >  	switch (dcfg->method) {
> >  	case IMX_RPROC_NONE:
> > @@ -699,6 +756,51 @@ static int imx_rproc_detect_mode(struct
> imx_rproc *priv)
> >  		if (res.a0)
> >  			priv->rproc->state = RPROC_DETACHED;
> >  		return 0;
> > +	case IMX_RPROC_SCU_API:
> > +		ret = imx_scu_get_handle(&priv->ipc_handle);
> > +		if (ret)
> > +			return ret;
> > +		ret = of_property_read_u32(dev->of_node, "fsl,resource-id",
> &priv->rsrc_id);
> > +		if (ret) {
> > +			dev_err(dev, "No fsl,resource-id property\n");
> > +			return ret;
> > +		}
> > +
> > +		/*
> > +		 * If Mcore resource is not owned by Acore partition, It is
> kicked by ROM,
> > +		 * and Linux could only do IPC with Mcore and nothing else.
> > +		 */
> > +		if (imx_sc_rm_is_resource_owned(priv->ipc_handle, priv-
> >rsrc_id))
> > +			return 0;
> 
> If imx_sc_rm_is_resource_owned() return '1' than the remote processor is
> under Linux's control and what follows below is not needed.  That is also
> coherent with the comment in [1].

Case 1: If M4 is owned by Linux, here directly return 0.
Case 2: If M4 is not owned by Linux, the following code after this line will set
state as RPROC_DETACHED.

Patch 3/6(this patch) is only to support case 2.
Patch 4/6 is to support case 1.

> 
> That is in contrast with what is happening in imx_rproc_put_scu().  There, if
> the remote processor is _not_ owned by Linux than the condition returns
> without calling imx_scu_irq_group_enable() and
> imx_scu_irq_unregister_notifier().  That seems to be a bug.

No. The two functions only needed when M4 is in a separate hardware partition.

The scu irq is only needed when M4 is out of linux control and need some
notification such as M4 is reset by SCU(System Control Unit). That linux got
notification that M4 is reset by SCU.

> 
> There is also a problem in patch 4/6 associated to that.

If the upper explanation eliminate your concern, "a problem in patch 4/6" should
not be a problem.

When M4 is owned by Linux, Linux need handle the power domain. If M4 is not owned
by Linux, SCU firmware will handle the power domain, and Linux has no permission to
touch that.

Thanks
Peng

> 
> Thanks,
> Mathieu
> 
> 
> [1].
> https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Felixir
> .bootlin.com%2Flinux%2Fv6.0-
> rc7%2Fsource%2Fdrivers%2Ffirmware%2Fimx%2Frm.c%23L24&amp;data=0
> 5%7C01%7Cpeng.fan%40nxp.com%7Cbe679e9a409a48b834b908daa015d92
> c%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C637998312946913
> 710%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2lu
> MzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&amp;sdata=
> JDRvoDGGgEiSmbhj3410V2DNxamZbDmMS0U2GvBnI74%3D&amp;reserved
> =0
> 
> > +
> > +		priv->rproc->state = RPROC_DETACHED;
> > +		priv->rproc->recovery_disabled = true;
> > +
> > +		/* Get partition id and enable irq in SCFW */
> > +		ret = imx_sc_rm_get_resource_owner(priv->ipc_handle,
> priv->rsrc_id, &pt);
> > +		if (ret) {
> > +			dev_err(dev, "not able to get resource owner\n");
> > +			return ret;
> > +		}
> > +
> > +		priv->rproc_pt = pt;
> > +		priv->rproc_nb.notifier_call = imx_rproc_partition_notify;
> > +
> > +		ret = imx_scu_irq_register_notifier(&priv->rproc_nb);
> > +		if (ret) {
> > +			dev_warn(dev, "register scu notifier failed.\n");
> > +			return ret;
> > +		}
> > +
> > +		ret =
> imx_scu_irq_group_enable(IMX_SC_IRQ_GROUP_REBOOTED, BIT(priv-
> >rproc_pt),
> > +					       true);
> > +		if (ret) {
> > +			imx_scu_irq_unregister_notifier(&priv->rproc_nb);
> > +			dev_warn(dev, "Enable irq failed.\n");
> > +			return ret;
> > +		}
> > +
> > +		return 0;
> >  	default:
> >  		break;
> >  	}
> > @@ -803,7 +905,7 @@ static int imx_rproc_probe(struct platform_device
> > *pdev)
> >
> >  	ret = imx_rproc_clk_enable(priv);
> >  	if (ret)
> > -		goto err_put_mbox;
> > +		goto err_put_scu;
> >
> >  	INIT_WORK(&priv->rproc_work, imx_rproc_vq_work);
> >
> > @@ -820,6 +922,8 @@ static int imx_rproc_probe(struct platform_device
> > *pdev)
> >
> >  err_put_clk:
> >  	clk_disable_unprepare(priv->clk);
> > +err_put_scu:
> > +	imx_rproc_put_scu(rproc);
> >  err_put_mbox:
> >  	imx_rproc_free_mbox(rproc);
> >  err_put_wkq:
> > @@ -837,6 +941,7 @@ static int imx_rproc_remove(struct
> platform_device
> > *pdev)
> >
> >  	clk_disable_unprepare(priv->clk);
> >  	rproc_del(rproc);
> > +	imx_rproc_put_scu(rproc);
> >  	imx_rproc_free_mbox(rproc);
> >  	destroy_workqueue(priv->workqueue);
> >  	rproc_free(rproc);
> > @@ -852,6 +957,7 @@ static const struct of_device_id
> imx_rproc_of_match[] = {
> >  	{ .compatible = "fsl,imx8mm-cm4", .data =
> &imx_rproc_cfg_imx8mq },
> >  	{ .compatible = "fsl,imx8mn-cm7", .data =
> &imx_rproc_cfg_imx8mn },
> >  	{ .compatible = "fsl,imx8mp-cm7", .data =
> &imx_rproc_cfg_imx8mn },
> > +	{ .compatible = "fsl,imx8qxp-cm4", .data =
> &imx_rproc_cfg_imx8qxp },
> >  	{ .compatible = "fsl,imx8ulp-cm33", .data =
> &imx_rproc_cfg_imx8ulp },
> >  	{ .compatible = "fsl,imx93-cm33", .data = &imx_rproc_cfg_imx93 },
> >  	{},
> > --
> > 2.37.1
> >

Powered by blists - more mailing lists