From 8d8cc9507bd79afbe5c29b5d82868269691152f9 Mon Sep 17 00:00:00 2001
From: Samuel Holland <samuel.holland@sifive.com>
Date: Wed, 18 Dec 2024 21:02:39 -0800
Subject: [PATCH] lib: utils: Mark RPMI drivers as experimental

These drivers were merged on an experimental basis without the RPMI
specification being frozen. As a result, they may not be compatible with
the frozen version of the RPMI protocol. Additionally, their devicetree
bindings have not been reviewed and are subject to change. Warn the user
that these drivers make no compatibility guarantees, and that their
behavior and devicetree bindings may change incompatibly in future
versions of OpenSBI.

Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
---
 include/sbi_utils/fdt/fdt_driver.h         | 1 +
 lib/utils/cppc/fdt_cppc_rpmi.c             | 1 +
 lib/utils/fdt/fdt_driver.c                 | 4 ++++
 lib/utils/hsm/fdt_hsm_rpmi.c               | 1 +
 lib/utils/mailbox/fdt_mailbox_rpmi_shmem.c | 1 +
 lib/utils/mpxy/fdt_mpxy_rpmi_mbox.c        | 1 +
 lib/utils/reset/fdt_reset_rpmi.c           | 1 +
 lib/utils/suspend/fdt_suspend_rpmi.c       | 1 +
 8 files changed, 11 insertions(+)

diff --git a/include/sbi_utils/fdt/fdt_driver.h b/include/sbi_utils/fdt/fdt_driver.h
index f6fd26f9..12ffe3f9 100644
--- a/include/sbi_utils/fdt/fdt_driver.h
+++ b/include/sbi_utils/fdt/fdt_driver.h
@@ -15,6 +15,7 @@ struct fdt_driver {
 	const struct fdt_match *match_table;
 	int (*init)(const void *fdt, int nodeoff,
 		    const struct fdt_match *match);
+	bool experimental;
 };
 
 /**
diff --git a/lib/utils/cppc/fdt_cppc_rpmi.c b/lib/utils/cppc/fdt_cppc_rpmi.c
index 4946ed14..95328404 100644
--- a/lib/utils/cppc/fdt_cppc_rpmi.c
+++ b/lib/utils/cppc/fdt_cppc_rpmi.c
@@ -370,4 +370,5 @@ static const struct fdt_match rpmi_cppc_match[] = {
 struct fdt_driver fdt_cppc_rpmi = {
 	.match_table = rpmi_cppc_match,
 	.init = rpmi_cppc_cold_init,
+	.experimental = true,
 };
diff --git a/lib/utils/fdt/fdt_driver.c b/lib/utils/fdt/fdt_driver.c
index 586ea8aa..f6707c0e 100644
--- a/lib/utils/fdt/fdt_driver.c
+++ b/lib/utils/fdt/fdt_driver.c
@@ -30,6 +30,10 @@ int fdt_driver_init_by_offset(const void *fdt, int nodeoff,
 			if (!fdt_stringlist_contains(prop, len, match->compatible))
 				continue;
 
+			if (driver->experimental)
+				sbi_printf("WARNING: %s driver is experimental and may change\n",
+					   match->compatible);
+
 			rc = driver->init(fdt, nodeoff, match);
 			if (rc < 0) {
 				const char *name;
diff --git a/lib/utils/hsm/fdt_hsm_rpmi.c b/lib/utils/hsm/fdt_hsm_rpmi.c
index 975d3484..66fa0fe2 100644
--- a/lib/utils/hsm/fdt_hsm_rpmi.c
+++ b/lib/utils/hsm/fdt_hsm_rpmi.c
@@ -359,4 +359,5 @@ static const struct fdt_match rpmi_hsm_match[] = {
 struct fdt_driver fdt_hsm_rpmi = {
 	.match_table = rpmi_hsm_match,
 	.init = rpmi_hsm_cold_init,
+	.experimental = true,
 };
diff --git a/lib/utils/mailbox/fdt_mailbox_rpmi_shmem.c b/lib/utils/mailbox/fdt_mailbox_rpmi_shmem.c
index 91db4e96..b8bd3cd6 100644
--- a/lib/utils/mailbox/fdt_mailbox_rpmi_shmem.c
+++ b/lib/utils/mailbox/fdt_mailbox_rpmi_shmem.c
@@ -768,6 +768,7 @@ struct fdt_mailbox fdt_mailbox_rpmi_shmem = {
 	.driver = {
 		.match_table = rpmi_shmem_mbox_match,
 		.init = rpmi_shmem_mbox_init,
+		.experimental = true,
 	},
 	.xlate = fdt_mailbox_simple_xlate,
 };
diff --git a/lib/utils/mpxy/fdt_mpxy_rpmi_mbox.c b/lib/utils/mpxy/fdt_mpxy_rpmi_mbox.c
index c09a4c52..78020eae 100644
--- a/lib/utils/mpxy/fdt_mpxy_rpmi_mbox.c
+++ b/lib/utils/mpxy/fdt_mpxy_rpmi_mbox.c
@@ -439,4 +439,5 @@ static const struct fdt_match mpxy_mbox_match[] = {
 struct fdt_driver fdt_mpxy_rpmi_mbox = {
 	.match_table = mpxy_mbox_match,
 	.init = mpxy_mbox_init,
+	.experimental = true,
 };
diff --git a/lib/utils/reset/fdt_reset_rpmi.c b/lib/utils/reset/fdt_reset_rpmi.c
index 1ec4396b..70826b96 100644
--- a/lib/utils/reset/fdt_reset_rpmi.c
+++ b/lib/utils/reset/fdt_reset_rpmi.c
@@ -138,4 +138,5 @@ static const struct fdt_match rpmi_reset_match[] = {
 struct fdt_driver fdt_reset_rpmi = {
 	.match_table = rpmi_reset_match,
 	.init = rpmi_reset_init,
+	.experimental = true,
 };
diff --git a/lib/utils/suspend/fdt_suspend_rpmi.c b/lib/utils/suspend/fdt_suspend_rpmi.c
index 11696648..07ff5198 100644
--- a/lib/utils/suspend/fdt_suspend_rpmi.c
+++ b/lib/utils/suspend/fdt_suspend_rpmi.c
@@ -135,4 +135,5 @@ static const struct fdt_match rpmi_suspend_match[] = {
 struct fdt_driver fdt_suspend_rpmi = {
 	.match_table = rpmi_suspend_match,
 	.init = rpmi_suspend_init,
+	.experimental = true,
 };