From: Luc Michel <luc.michel@amd.com>

The JEDEC standards specifies a sleep state where the eMMC won't answer
any command appart from RESET and WAKEUP and go to low power state.
Implement this state and the corresponding command number 5.

Signed-off-by: Luc Michel <luc.michel@amd.com>
Signed-off-by: Francisco Iglesias <francisco.iglesias@amd.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
 hw/sd/sd.c | 47 +++++++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 45 insertions(+), 2 deletions(-)

diff --git a/hw/sd/sd.c b/hw/sd/sd.c
index 0f9bab105e..bd77853419 100644
--- a/hw/sd/sd.c
+++ b/hw/sd/sd.c
@@ -1182,8 +1182,19 @@ static sd_rsp_type_t sd_cmd_to_sendingdata(SDState *sd, SDRequest req,
 /* CMD0 */
 static sd_rsp_type_t sd_cmd_GO_IDLE_STATE(SDState *sd, SDRequest req)
 {
-    sd->state = sd_idle_state;
-    sd_reset(DEVICE(sd));
+    if (sd->state == sd_sleep_state) {
+        switch (req.arg) {
+        case 0x00000000:
+        case 0xf0f0f0f0:
+            break;
+        default:
+            return sd_r0;
+        }
+    }
+    if (sd->state != sd_inactive_state) {
+        sd->state = sd_idle_state;
+        sd_reset(DEVICE(sd));
+    }
 
     return sd_is_spi(sd) ? sd_r1 : sd_r0;
 }
@@ -1246,6 +1257,30 @@ static sd_rsp_type_t emmc_cmd_SET_RELATIVE_ADDR(SDState *sd, SDRequest req)
     }
 }
 
+/* CMD5 */
+static sd_rsp_type_t emmc_cmd_sleep_awake(SDState *sd, SDRequest req)
+{
+    bool do_sleep = extract32(req.arg, 15, 1);
+
+    switch (sd->state) {
+    case sd_sleep_state:
+        if (!do_sleep) {
+            /* Awake */
+            sd->state = sd_standby_state;
+        }
+        return sd_r1b;
+
+    case sd_standby_state:
+        if (do_sleep) {
+            sd->state = sd_sleep_state;
+        }
+        return sd_r1b;
+
+    default:
+        return sd_invalid_state_for_cmd(sd, req);
+    }
+}
+
 /* CMD6 */
 static sd_rsp_type_t sd_cmd_SWITCH_FUNCTION(SDState *sd, SDRequest req)
 {
@@ -1648,6 +1683,7 @@ static sd_rsp_type_t sd_cmd_APP_CMD(SDState *sd, SDRequest req)
     case sd_ready_state:
     case sd_identification_state:
     case sd_inactive_state:
+    case sd_sleep_state:
         return sd_invalid_state_for_cmd(sd, req);
     case sd_idle_state:
         if (!sd_is_spi(sd) && sd_req_get_rca(sd, req) != 0x0000) {
@@ -1969,6 +2005,12 @@ int sd_do_command(SDState *sd, SDRequest *req,
         req->cmd &= 0x3f;
     }
 
+    if (sd->state == sd_sleep_state && req->cmd) {
+        qemu_log_mask(LOG_GUEST_ERROR, "SD: Card is sleeping\n");
+        rtype = sd_r0;
+        goto send_response;
+    }
+
     if (sd->card_status & CARD_IS_LOCKED) {
         if (!cmd_valid_while_locked(sd, req->cmd)) {
             sd->card_status |= ILLEGAL_COMMAND;
@@ -2420,6 +2462,7 @@ static const SDProto sd_proto_emmc = {
         [2]  = {0,  sd_bcr,  "ALL_SEND_CID", sd_cmd_ALL_SEND_CID},
         [3]  = {0,  sd_ac,   "SET_RELATIVE_ADDR", emmc_cmd_SET_RELATIVE_ADDR},
         [4]  = {0,  sd_bc,   "SEND_DSR", sd_cmd_unimplemented},
+        [5]  = {0,  sd_ac,   "SLEEP/AWAKE", emmc_cmd_sleep_awake},
         [7]  = {0,  sd_ac,   "(DE)SELECT_CARD", sd_cmd_DE_SELECT_CARD},
         [9]  = {0,  sd_ac,   "SEND_CSD", sd_cmd_SEND_CSD},
         [10] = {0,  sd_ac,   "SEND_CID", sd_cmd_SEND_CID},
-- 
2.41.0