[PATCH] hw/sd: Correct card status clear conditions in SPI-mode

[frank . chang]

From: Frank Chang <frank.chang@sifive.com>

In SPI-mode, unlike SD-mode, card status bits: ILLEGAL_COMMAND and
COM_CRC_ERROR have type C ("cleared by read") clear conditions.
Also, type B ("cleared on valid command") clear condition is not
supported in SPI-mode. As the "In idle state" bit in SPI-mode has type A
("according to current state") clear condition, the CURRENT_STATE bits
in an SPI-mode response should be the SD card's state after the command
is executed, instead of the state when it received the preceding
command.

This patch redefines the card status clear conditions used in SD-mode
and SPI-mode according to SD spec.

Signed-off-by: Frank Chang <frank.chang@sifive.com>
---
 hw/sd/sd.c | 84 ++++++++++++++++++++++++++++++++++++++----------------
 1 file changed, 59 insertions(+), 25 deletions(-)

diff --git a/hw/sd/sd.c b/hw/sd/sd.c
index cd67a7bac8..4c6c1b9424 100644
--- a/hw/sd/sd.c
+++ b/hw/sd/sd.c
@@ -479,24 +479,50 @@ FIELD(CSR, OUT_OF_RANGE,               31,  1)
 #define CARD_STATUS_A           (R_CSR_READY_FOR_DATA_MASK \
                                | R_CSR_CARD_ECC_DISABLED_MASK \
                                | R_CSR_CARD_IS_LOCKED_MASK)
-#define CARD_STATUS_B           (R_CSR_CURRENT_STATE_MASK \
-                               | R_CSR_ILLEGAL_COMMAND_MASK \
-                               | R_CSR_COM_CRC_ERROR_MASK)
-#define CARD_STATUS_C           (R_CSR_AKE_SEQ_ERROR_MASK \
-                               | R_CSR_APP_CMD_MASK \
-                               | R_CSR_ERASE_RESET_MASK \
-                               | R_CSR_WP_ERASE_SKIP_MASK \
-                               | R_CSR_CSD_OVERWRITE_MASK \
-                               | R_CSR_ERROR_MASK \
-                               | R_CSR_CC_ERROR_MASK \
-                               | R_CSR_CARD_ECC_FAILED_MASK \
-                               | R_CSR_LOCK_UNLOCK_FAILED_MASK \
-                               | R_CSR_WP_VIOLATION_MASK \
-                               | R_CSR_ERASE_PARAM_MASK \
-                               | R_CSR_ERASE_SEQ_ERROR_MASK \
-                               | R_CSR_BLOCK_LEN_ERROR_MASK \
-                               | R_CSR_ADDRESS_ERROR_MASK \
-                               | R_CSR_OUT_OF_RANGE_MASK)
+
+static uint32_t sd_card_status_b(SDState *sd)
+{
+    uint32_t sd_mask = R_CSR_CURRENT_STATE_MASK |
+                       R_CSR_ILLEGAL_COMMAND_MASK |
+                       R_CSR_COM_CRC_ERROR_MASK;
+
+    /* SPI-mode dosen't have type B clear condition. */
+    return !sd->spi ? sd_mask : 0;
+}
+
+static uint32_t sd_card_status_c(SDState *sd) {
+    uint32_t sd_mask = R_CSR_AKE_SEQ_ERROR_MASK |
+                       R_CSR_APP_CMD_MASK |
+                       R_CSR_ERASE_RESET_MASK |
+                       R_CSR_WP_ERASE_SKIP_MASK |
+                       R_CSR_CSD_OVERWRITE_MASK |
+                       R_CSR_ERROR_MASK |
+                       R_CSR_CC_ERROR_MASK |
+                       R_CSR_CARD_ECC_FAILED_MASK |
+                       R_CSR_LOCK_UNLOCK_FAILED_MASK |
+                       R_CSR_WP_VIOLATION_MASK |
+                       R_CSR_ERASE_PARAM_MASK |
+                       R_CSR_ERASE_SEQ_ERROR_MASK |
+                       R_CSR_BLOCK_LEN_ERROR_MASK |
+                       R_CSR_ADDRESS_ERROR_MASK |
+                       R_CSR_OUT_OF_RANGE_MASK;
+    uint32_t spi_mask = R_CSR_ERASE_RESET_MASK |
+                        R_CSR_LOCK_UNLOCK_FAILED_MASK |
+                        R_CSR_WP_ERASE_SKIP_MASK |
+                        R_CSR_CSD_OVERWRITE_MASK |
+                        R_CSR_ERROR_MASK |
+                        R_CSR_CC_ERROR_MASK |
+                        R_CSR_CARD_ECC_FAILED_MASK |
+                        R_CSR_ILLEGAL_COMMAND_MASK |
+                        R_CSR_COM_CRC_ERROR_MASK|
+                        R_CSR_WP_VIOLATION_MASK |
+                        R_CSR_ERASE_PARAM_MASK |
+                        R_CSR_ERASE_SEQ_ERROR_MASK |
+                        R_CSR_ADDRESS_ERROR_MASK |
+                        R_CSR_OUT_OF_RANGE_MASK;
+
+    return !sd->spi ? sd_mask : spi_mask;
+}
 
 static void sd_set_cardstatus(SDState *sd)
 {
@@ -522,7 +548,7 @@ static void sd_response_r1_make(SDState *sd, uint8_t 
*response)
     stl_be_p(response, sd->card_status);
 
     /* Clear the "clear on read" status bits */
-    sd->card_status &= ~CARD_STATUS_C;
+    sd->card_status &= ~sd_card_status_c(sd);
 }
 
 static void sd_response_r3_make(SDState *sd, uint8_t *response)
@@ -537,7 +563,7 @@ static void sd_response_r6_make(SDState *sd, uint8_t 
*response)
     status = ((sd->card_status >> 8) & 0xc000) |
              ((sd->card_status >> 6) & 0x2000) |
               (sd->card_status & 0x1fff);
-    sd->card_status &= ~(CARD_STATUS_C & 0xc81fff);
+    sd->card_status &= ~(sd_card_status_c(sd) & 0xc81fff);
     stw_be_p(response + 0, sd->rca);
     stw_be_p(response + 2, status);
 }
@@ -1757,12 +1783,20 @@ int sd_do_command(SDState *sd, SDRequest *req,
     if (rtype == sd_illegal) {
         sd->card_status |= ILLEGAL_COMMAND;
     } else {
-        /* Valid command, we can update the 'state before command' bits.
-         * (Do this now so they appear in r1 responses.)
-         */
         sd->current_cmd = req->cmd;
         sd->card_status &= ~CURRENT_STATE;
-        sd->card_status |= (last_state << 9);
+
+        if (!sd->spi) {
+            /* Valid command, we can update the 'state before command' bits.
+             * (Do this now so they appear in r1 responses.)
+             */
+            sd->card_status |= (last_state << 9);
+        } else {
+            /* Type B ("clear on valid command") is not supported
+             * in SPI-mode.
+             */
+            sd->card_status |= (sd->state << 9);
+        }
     }
 
 send_response:
@@ -1811,7 +1845,7 @@ send_response:
         /* Clear the "clear on valid command" status bits now we've
          * sent any response
          */
-        sd->card_status &= ~CARD_STATUS_B;
+        sd->card_status &= ~sd_card_status_b(sd);
     }
 
 #ifdef DEBUG_SD
-- 
2.31.1