U-Boot queries the FIFO water level to reduce checking status register
when doing PIO SD card operation.
Report a FIFO water level of 1 when data is ready, to prevent the code
from trying to read 0 words from the FIFO each time.
Signed-off-by: Icenowy Zheng <uwu@icenowy.me>
Message-id:
20220520124200.
2112699-1-uwu@icenowy.me
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
};
enum {
+ SD_STAR_FIFO_EMPTY = (1 << 2),
SD_STAR_CARD_PRESENT = (1 << 8),
+ SD_STAR_FIFO_LEVEL_1 = (1 << 17),
};
enum {
break;
case REG_SD_STAR: /* Status */
res = s->status;
+ if (sdbus_data_ready(&s->sdbus)) {
+ res |= SD_STAR_FIFO_LEVEL_1;
+ } else {
+ res |= SD_STAR_FIFO_EMPTY;
+ }
break;
case REG_SD_FWLR: /* FIFO Water Level */
res = s->fifo_wlevel;