firmware: tegra: Add helper to check for supported MRQs

Add a helper function to check that firmware is supporting a given MRQ
command.
Signed-off-by: Timo Alho <talho@nvidia.com>
Acked-by: Sivaram Nair <sivaramn@nvidia.com>
Acked-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>

drivers/firmware/tegra/bpmp.c

@@ -470,6 +470,31 @@ void tegra_bpmp_free_mrq(struct tegra_bpmp *bpmp, unsigned int mrq, void *data)
 }
 EXPORT_SYMBOL_GPL(tegra_bpmp_free_mrq);
 
+bool tegra_bpmp_mrq_is_supported(struct tegra_bpmp *bpmp, unsigned int mrq)
+{
+	struct mrq_query_abi_request req = { .mrq = cpu_to_le32(mrq) };
+	struct mrq_query_abi_response resp;
+	struct tegra_bpmp_message msg = {
+		.mrq = MRQ_QUERY_ABI,
+		.tx = {
+			.data = &req,
+			.size = sizeof(req),
+		},
+		.rx = {
+			.data = &resp,
+			.size = sizeof(resp),
+		},
+	};
+	int ret;
+
+	ret = tegra_bpmp_transfer(bpmp, &msg);
+	if (ret || msg.rx.ret)
+		return false;
+
+	return resp.status == 0;
+}
+EXPORT_SYMBOL_GPL(tegra_bpmp_mrq_is_supported);
+
 static void tegra_bpmp_mrq_handle_ping(unsigned int mrq,
 				       struct tegra_bpmp_channel *channel,
 				       void *data)

include/soc/tegra/bpmp.h

@@ -129,6 +129,7 @@ int tegra_bpmp_request_mrq(struct tegra_bpmp *bpmp, unsigned int mrq,
 			   tegra_bpmp_mrq_handler_t handler, void *data);
 void tegra_bpmp_free_mrq(struct tegra_bpmp *bpmp, unsigned int mrq,
 			 void *data);
+bool tegra_bpmp_mrq_is_supported(struct tegra_bpmp *bpmp, unsigned int mrq);
 #else
 static inline struct tegra_bpmp *tegra_bpmp_get(struct device *dev)
 {
@@ -164,6 +165,12 @@ static inline void tegra_bpmp_free_mrq(struct tegra_bpmp *bpmp,
 				       unsigned int mrq, void *data)
 {
 }
+
+static inline bool tegra_bpmp_mrq_is_supported(struct tegra_bpmp *bpmp,
+					      unsigned int mrq)
+{
+	return false;
+}
 #endif
 
 #if IS_ENABLED(CONFIG_CLK_TEGRA_BPMP)