From: Bin Meng <[email protected]>
Per the SD spec, a valid data block is suffixed with a 16-bit CRC
generated by the standard CCITT polynomial x16+x12+x5+1. This part
is currently missing in the ssi-sd state machine. Without it, all
data block transfer fails in guest software because the expected
CRC16 is missing on the data out line.
Fixes: 775616c3ae8c ("Partial SD card SPI mode support")
Signed-off-by: Bin Meng <[email protected]>
Acked-by: Alistair Francis <[email protected]>
Reviewed-by: Philippe Mathieu-Daudé <[email protected]>
Message-Id: <[email protected]>
[PMD: Change VMState version id 3 -> 4,
check s->mode validity in post_load()]
Signed-off-by: Philippe Mathieu-Daudé <[email protected]>
---
hw/sd/ssi-sd.c | 23 ++++++++++++++++++++---
1 file changed, 20 insertions(+), 3 deletions(-)
diff --git a/hw/sd/ssi-sd.c b/hw/sd/ssi-sd.c
index d97646795a2..08852dc8d4b 100644
--- a/hw/sd/ssi-sd.c
+++ b/hw/sd/ssi-sd.c
@@ -17,6 +17,7 @@
#include "hw/qdev-properties.h"
#include "hw/sd/sd.h"
#include "qapi/error.h"
+#include "qemu/crc-ccitt.h"
#include "qemu/module.h"
#include "qom/object.h"
@@ -40,6 +41,7 @@ typedef enum {
SSI_SD_RESPONSE,
SSI_SD_DATA_START,
SSI_SD_DATA_READ,
+ SSI_SD_DATA_CRC16,
} ssi_sd_mode;
struct ssi_sd_state {
@@ -48,6 +50,7 @@ struct ssi_sd_state {
int cmd;
uint8_t cmdarg[4];
uint8_t response[5];
+ uint16_t crc16;
int32_t arglen;
int32_t response_pos;
int32_t stopping;
@@ -194,12 +197,24 @@ static uint32_t ssi_sd_transfer(SSIPeripheral *dev,
uint32_t val)
case SSI_SD_DATA_START:
DPRINTF("Start read block\n");
s->mode = SSI_SD_DATA_READ;
+ s->response_pos = 0;
return 0xfe;
case SSI_SD_DATA_READ:
val = sdbus_read_byte(&s->sdbus);
+ s->crc16 = crc_ccitt_false(s->crc16, (uint8_t *)&val, 1);
if (!sdbus_data_ready(&s->sdbus)) {
DPRINTF("Data read end\n");
+ s->mode = SSI_SD_DATA_CRC16;
+ }
+ return val;
+ case SSI_SD_DATA_CRC16:
+ val = (s->crc16 & 0xff00) >> 8;
+ s->crc16 <<= 8;
+ s->response_pos++;
+ if (s->response_pos == 2) {
+ DPRINTF("CRC16 read end\n");
s->mode = SSI_SD_CMD;
+ s->response_pos = 0;
}
return val;
}
@@ -211,7 +226,7 @@ static int ssi_sd_post_load(void *opaque, int version_id)
{
ssi_sd_state *s = (ssi_sd_state *)opaque;
- if (s->mode > SSI_SD_DATA_READ) {
+ if (s->mode > SSI_SD_DATA_CRC16) {
return -EINVAL;
}
if (s->mode == SSI_SD_CMDARG &&
@@ -229,14 +244,15 @@ static int ssi_sd_post_load(void *opaque, int version_id)
static const VMStateDescription vmstate_ssi_sd = {
.name = "ssi_sd",
- .version_id = 3,
- .minimum_version_id = 3,
+ .version_id = 4,
+ .minimum_version_id = 4,
.post_load = ssi_sd_post_load,
.fields = (VMStateField []) {
VMSTATE_UINT32(mode, ssi_sd_state),
VMSTATE_INT32(cmd, ssi_sd_state),
VMSTATE_UINT8_ARRAY(cmdarg, ssi_sd_state, 4),
VMSTATE_UINT8_ARRAY(response, ssi_sd_state, 5),
+ VMSTATE_UINT16(crc16, ssi_sd_state),
VMSTATE_INT32(arglen, ssi_sd_state),
VMSTATE_INT32(response_pos, ssi_sd_state),
VMSTATE_INT32(stopping, ssi_sd_state),
@@ -288,6 +304,7 @@ static void ssi_sd_reset(DeviceState *dev)
s->cmd = 0;
memset(s->cmdarg, 0, sizeof(s->cmdarg));
memset(s->response, 0, sizeof(s->response));
+ s->crc16 = 0;
s->arglen = 0;
s->response_pos = 0;
s->stopping = 0;
--
2.26.2
