Hi Frank,

On Tue, Oct 28, 2025 at 12:16:56PM -0400, Frank Li wrote:

On Tue, Oct 28, 2025 at 04:18:03PM +0800, Peng Fan wrote:

quoted

i.MX95 features a Cortex-M33 core, six Cortex-A55 cores, and
one Cortex-M7 core. The System Control Management Interface(SCMI)
firmware runs on the M33 core. The i.MX95 SCMI firmware named System
Manager(SM) includes vendor extension protocols, Logical Machine
Management(LMM) protocol and CPU protocol and etc.

...

quoted

+	depends on IMX_SCMI_CPU_DRV || !IMX_SCMI_CPU_DRV
+	depends on IMX_SCMI_LMM_DRV || !IMX_SCMI_LMM_DRV

what's means IMX_SCMI_LMM_DRV || !IMX_SCMI_LMM_DRV here, which is the same
config

This is to make sure when IMX_SCMI_CPU_DRV or IMX_SCMI_LMM_DRV is module built,
imx_rproc should also be built as module.

quoted

 	select MAILBOX
 	help

...

quoted

+	 */
+	if (priv->flags & IMX_RPROC_FLAGS_SM_CPU_OP)
+		return 0;

You already have imx_rproc_sm_lmm_stat[stop](),
why not use imx_rproc_sm_lmm_prepare();

imx_rproc_sm_cpu_prepare() should be empty. So needn't check
IMX_RPROC_FLAGS_SM_CPU_OP.

I will add below in detect_mode(), and no need imx_rproc_sm_cpu_prepare.

priv->ops.prepare = &imx_rproc_sm_lmm_prepare;

quoted

+
+	/*
 static int imx_rproc_prepare(struct rproc *rproc)
 {
 	struct imx_rproc *priv = rproc->priv;

@@ -532,7 +639,10 @@ static int imx_rproc_prepare(struct rproc *rproc)
 		rproc_add_carveout(rproc, mem);
 	}

-	return  0;
+	if (priv->ops.detect_mode == imx_rproc_sm_detect_mode)
+		return imx_rproc_sm_prepare(rproc);

Here I will change to:
if (priv->ops.prepare)
    return priv->ops.prepare();

quoted

+
+	return 0;
 }

 static int imx_rproc_parse_fw(struct rproc *rproc, const struct firmware *fw)

@@ -991,6 +1101,83 @@ static int imx_rproc_scu_api_detect_mode(struct rproc *rproc)
 	return 0;
 }

+	 */
+	if (dcfg->lmid == info.lmid) {
+		priv->ops.start = &imx_rproc_sm_cpu_start;
+		priv->ops.stop = &imx_rproc_sm_cpu_stop;

you have switch callback here, also swtich imx_rproc_sm_prepare()

Yes, as above.
priv->ops.prepare = &imx_rproc_sm_lmm_prepare;

quoted

+		priv->flags |= IMX_RPROC_FLAGS_SM_CPU_OP;
+		dev_info(dev, "Using CPU Protocol OPS\n");
+
+		return 0;
+	}
+
+	dev_info(dev, "Using LMM Protocol OPS\n");
+	priv->ops.start = &imx_rproc_sm_lmm_start;
+	priv->ops.stop = &imx_rproc_sm_lmm_stop;
+	priv->flags |= IMX_RPROC_FLAGS_SM_LMM_OP;

Most likely

bool b = (dcfg->lmid == info.lmid);
priv->ops.start = b ? &imx_rproc_sm_cpu_start : &imx_rproc_sm_lmm_start;
...
or
if (b)	{
} else {
}

to do ops switch.

ok.

quoted

+
+	/*
+	 * Use power on to do permission check. If rproc is in different Logical Machine,
+	 * and linux has permission to handle the Logical Machine, set
+	 * IMX_RPROC_FLAGS_SM_LMM_AVAIL.
+	 */
+	ret = scmi_imx_lmm_operation(dcfg->lmid, SCMI_IMX_LMM_POWER_ON, 0);
+	if (ret != 0) {
+		if (ret == -EACCES) {
+			/* Not under Linux Control, so only do IPC between rproc and Linux */
+			dev_info(priv->dev, "lmm(%d) not under Linux Control\n", dcfg->lmid);
+			return 0;
+		}
+
+		dev_info(priv->dev, "power on lmm(%d) failed: %d\n", dcfg->lmid, ret);
+		return ret;
+	}
+
+	priv->flags |= IMX_RPROC_FLAGS_SM_LMM_AVAIL;
+
+	/* rproc is started before boot Linux, so do NOT shutdown the LM */
+	if (started)
+		return 0;
+
+	/* Permission check finished, shutdown the LM to save power */
+	ret = scmi_imx_lmm_operation(dcfg->lmid, SCMI_IMX_LMM_SHUTDOWN, 0);
+	if (ret) {
+		dev_err(priv->dev, "shutdown lmm(%d) failed: %d\n", dcfg->lmid, ret);
+		return ret;
+	}

look like this block should be in imx_rproc_sm_prepare()?

This should be kept here. permission check flow:

power on m7 lm
  |
  | success(indicating linux control rproc LM)
         -> check m7 booted by U-Boot
	              |-> If yes, keep power.
		      |-> If no, shutdown to save power.
                                                     
Thanks,
Peng

Frank

quoted

+
+	return 0;
+}
+
 static int imx_rproc_detect_mode(struct imx_rproc *priv)
 {
 	/*

@@ -1166,6 +1353,10 @@ static const struct imx_rproc_plat_ops imx_rproc_ops_scu_api = {
 	.detect_mode	= imx_rproc_scu_api_detect_mode,
 };

+static const struct imx_rproc_plat_ops imx_rproc_ops_sm = {
+	.detect_mode	= imx_rproc_sm_detect_mode,
+};
+
 static const struct imx_rproc_dcfg imx_rproc_cfg_imx8mn_mmio = {
 	.src_reg	= IMX7D_SRC_SCR,
 	.src_mask	= IMX7D_M4_RST_MASK,

diff --git a/drivers/remoteproc/imx_rproc.h b/drivers/remoteproc/imx_rproc.h
index aeed08bdfb5619c7afd7201589f417cfd6745818..b8a30df92d3bdeb915e33551235d555b947d0b16 100644
--- a/drivers/remoteproc/imx_rproc.h
+++ b/drivers/remoteproc/imx_rproc.h

@@ -51,6 +51,9 @@ struct imx_rproc_dcfg {
 	enum imx_rproc_method		method;
 	u32				flags;
 	const struct imx_rproc_plat_ops	*ops;
+	/* For System Manager(SM) based SoCs, the IDs are from SM firmware */
+	u32				cpuid;
+	u32				lmid;
 };

 #endif /* _IMX_RPROC_H */

--

2.37.1