[PATCH v17 5/7] firmware: arm_rmm: Activate the RMM

Suzuki K Poulose suzuki.poulose at arm.com
Mon Sep 7 02:59:39 PDT 2026


From: Steven Price <steven.price at arm.com>

Activate the RMM after the basic configuration. This is a memory transferring,
stateful operation.

Signed-off-by: Steven Price <steven.price at arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose at arm.com>
---
Changes since v16:
 * Split into a new patch
---
 drivers/firmware/arm_rmm/rmi.c | 17 +++++++++++++++--
 include/linux/arm-rmi-cmds.h   | 11 +++++++++++
 2 files changed, 26 insertions(+), 2 deletions(-)

diff --git a/drivers/firmware/arm_rmm/rmi.c b/drivers/firmware/arm_rmm/rmi.c
index 42c973c3a98bb..d969c8738efde 100644
--- a/drivers/firmware/arm_rmm/rmi.c
+++ b/drivers/firmware/arm_rmm/rmi.c
@@ -641,7 +641,8 @@ static int rmi_configure(void)
 
 static int __init arm64_init_rmi(void)
 {
-	int ret;
+	int ret = 0;
+	struct rmi_sro_state *sro = NULL;
 
 	/* Continue without realm support if we can't agree on a version */
 	ret = rmi_check_version();
@@ -656,7 +657,19 @@ static int __init arm64_init_rmi(void)
 	if (ret)
 		return ret;
 
-	return 0;
+	/* Activate the RMM */
+	sro = kmalloc_obj(*sro);
+	if (!sro)
+		return -ENOMEM;
+
+	ret = rmi_rmm_activate(sro);
+	if (ret) {
+		pr_err("RMM activate failed\n");
+		ret = ret < 0 ? ret : -ENXIO;
+	}
+
+	kfree(sro);
+	return ret;
 }
 
 /*
diff --git a/include/linux/arm-rmi-cmds.h b/include/linux/arm-rmi-cmds.h
index fed0f3421895d..dea7c7004d35f 100644
--- a/include/linux/arm-rmi-cmds.h
+++ b/include/linux/arm-rmi-cmds.h
@@ -64,6 +64,17 @@ static inline int rmi_rmm_config_set(unsigned long cfg_ptr)
 	return res.a0;
 }
 
+/**
+ * rmi_rmm_activate() - Activate the RMM
+ * @sro: Preallocated SRO context to be used
+ *
+ * Return: 0 on success, positive RMI result code or negative Linux error code
+ */
+static inline long rmi_rmm_activate(struct rmi_sro_state *sro)
+{
+	return rmi_sro_memxfer_cmd(sro, GFP_KERNEL, SMC_RMI_RMM_ACTIVATE);
+}
+
 /**
  * rmi_features() - Read feature register
  * @index: Feature register index
-- 
2.43.0




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