[PATCH v16 02/45] firmware: arm_rmm: Add wrappers for direct RMI calls

[Steven Price <steven.price@arm.com>]

The wrappers make the call sites easier to read and deal with the
boilerplate of handling the error codes from the RMM.

Signed-off-by: Steven Price <steven.price@arm.com>
---
Changes from v15:
 * Split out wrappers for realms to a separate commit.
 * Wrappers that have output arguments now only write the output when
   the command completes successfully.
Changes from v14:
 * Update to RMM v2.0-bet2 spec.
 * Move SRO related wrappers to a later patch due to dependencies.
 * Common wrappers are split into include/linux/arm-rmi-cmds.h.
Changes from v13:
 * Update to RMM v2.0-bet1 spec including some SRO support (there still
   some FIXMEs where SRO support is incomplete).
Changes from v12:
 * Update to RMM v2.0 specification
Changes from v8:
 * Switch from arm_smccc_1_2_smc() to arm_smccc_1_2_invoke() in
   rmi_rtt_read_entry() for consistency.
Changes from v7:
 * Minor renaming of parameters and updated comments
Changes from v5:
 * Further improve comments
Changes from v4:
 * Improve comments
Changes from v2:
 * Make output arguments optional.
 * Mask RIPAS value rmi_rtt_read_entry()
 * Drop unused rmi_rtt_get_phys()
---
 include/linux/arm-rmi-cmds.h | 83 ++++++++++++++++++++++++++++++++++++
 1 file changed, 83 insertions(+)
 create mode 100644 include/linux/arm-rmi-cmds.h

diff --git a/include/linux/arm-rmi-cmds.h b/include/linux/arm-rmi-cmds.h
new file mode 100644
index 000000000000..5ee94da96e4a
--- /dev/null
+++ b/include/linux/arm-rmi-cmds.h
@@ -0,0 +1,83 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2026 ARM Ltd.
+ */
+
+#ifndef __LINUX_ARM_RMI_CMDS_H_
+#define __LINUX_ARM_RMI_CMDS_H_
+
+#include <linux/arm-smccc-rmi.h>
+#include <linux/bug.h>
+#include <linux/types.h>
+
+#include <asm/page.h>
+
+/**
+ * rmi_rmm_config_set() - Configure the RMM
+ * @cfg_ptr: PA of a struct rmm_config
+ *
+ * Sets configuration options on the RMM.
+ *
+ * Return: RMI return code
+ */
+static inline int rmi_rmm_config_set(unsigned long cfg_ptr)
+{
+	struct arm_smccc_res res;
+
+	arm_smccc_1_1_invoke(SMC_RMI_RMM_CONFIG_SET, cfg_ptr, &res);
+
+	return res.a0;
+}
+
+/**
+ * rmi_granule_tracking_get() - Get configuration of a Granule tracking region
+ * @start: Base PA of the tracking region
+ * @end: End of the PA region
+ * @out_category: Memory category
+ * @out_state: Tracking region state
+ * @out_top: Top of the memory region
+ *
+ * Return: RMI return code
+ */
+static inline int rmi_granule_tracking_get(unsigned long start,
+					   unsigned long end,
+					   unsigned long *out_category,
+					   unsigned long *out_state,
+					   unsigned long *out_top)
+{
+	struct arm_smccc_res res;
+
+	arm_smccc_1_1_invoke(SMC_RMI_GRANULE_TRACKING_GET, start, end, &res);
+
+	if (res.a0 == RMI_SUCCESS) {
+		if (out_category)
+			*out_category = res.a1;
+		if (out_state)
+			*out_state = res.a2;
+		if (out_top)
+			*out_top = res.a3;
+	}
+
+	return res.a0;
+}
+
+/**
+ * rmi_features() - Read feature register
+ * @index: Feature register index
+ * @out: Feature register value is written to this pointer
+ *
+ * Return: RMI return code
+ */
+static inline int rmi_features(unsigned long index, unsigned long *out)
+{
+	struct arm_smccc_res res;
+
+	arm_smccc_1_1_invoke(SMC_RMI_FEATURES, index, &res);
+
+	if (res.a0 == RMI_SUCCESS && out)
+		*out = res.a1;
+
+	return res.a0;
+}
+
+#endif
-- 
2.43.0