uniphier: revise SCP protocol handshake

When the SoC issues a command IRQ to SCP, SCP sets STMTOBEIRQ as ACK.
The SoC must wait for it before issuing the next command.

This commit makes sure to meet the requirement.

Signed-off-by: Dai Okamura <okamura.dai@socionext.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

diff --git a/plat/socionext/uniphier/uniphier_scp.c b/plat/socionext/uniphier/uniphier_scp.c
index 9a921c4a95d11ecfe9e2e589eb7c2774fc3c4073..58eb72eff0f94fdf4ea5fd7dcb46ddbea66c314a 100644 (file)
--- a/plat/socionext/uniphier/uniphier_scp.c
+++ b/plat/socionext/uniphier/uniphier_scp.c
@@ -12,7 +12,9 @@
 #define UNIPHIER_ROM_RSV3              0x5980120c
 
 #define UNIPHIER_STMBE2COM             0x5f800030
+#define UNIPHIER_STMTOBEIRQ            0x5f800060
 #define UNIPHIER_BETOSTMIRQ0PT         0x5f800070
+#define UNIPHIER_BEIRQCLRPT            0x5f800072
 
 #define UNIPHIER_SCP_READY_MAGIC       0x0000b6a5
 
@@ -59,6 +61,10 @@ static void uniphier_scp_send_packet(const uint8_t *packet, int packet_len)
        }
 
        mmio_write_8(UNIPHIER_BETOSTMIRQ0PT, 0x55);
+
+       while (!(mmio_read_32(UNIPHIER_STMTOBEIRQ) & BIT(1)))
+               ;
+       mmio_write_8(UNIPHIER_BEIRQCLRPT, BIT(1) | BIT(0));
 }
 
 static void uniphier_scp_send_cmd(const uint8_t *cmd, int cmd_len)