| Message ID | 20210123104016.17485-4-bmeng.cn@gmail.com |
|---|---|
| State | New |
| Headers | show |
| Series | hw/riscv: sifive_u: Add missing SPI support | expand |
On 1/23/21 11:39 AM, Bin Meng wrote: > From: Bin Meng <bin.meng@windriver.com> > > Per the "Physical Layer Specification Version 8.00" chapter 7.5.1, > "Command/Response", there is a minimum 8 clock cycles (Ncr) before > the card response shows up on the data out line. However current > implementation jumps directly to the sending response state after > all 6 bytes command is received, which is a spec violation. > > Add a new state PREP_RESP in the ssi-sd state machine to handle it. > > Fixes: 775616c3ae8c ("Partial SD card SPI mode support") > Signed-off-by: Bin Meng <bin.meng@windriver.com> > Reviewed-by: Pragnesh Patel <pragnesh.patel@sifive.com> > Tested-by: Pragnesh Patel <pragnesh.patel@sifive.com> > > --- > > Changes in v2: > - Add a debug printf in the state handling codes > > hw/sd/ssi-sd.c | 7 ++++++- > 1 file changed, 6 insertions(+), 1 deletion(-) > > diff --git a/hw/sd/ssi-sd.c b/hw/sd/ssi-sd.c > index 9a75e0095c..043e270066 100644 > --- a/hw/sd/ssi-sd.c > +++ b/hw/sd/ssi-sd.c > @@ -36,6 +36,7 @@ do { fprintf(stderr, "ssi_sd: error: " fmt , ## __VA_ARGS__);} while (0) > typedef enum { > SSI_SD_CMD = 0, > SSI_SD_CMDARG, > + SSI_SD_PREP_RESP, Another migration change. Otherwise (trusting you with the spec): Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org> > SSI_SD_RESPONSE, > SSI_SD_DATA_START, > SSI_SD_DATA_READ, > @@ -163,12 +164,16 @@ static uint32_t ssi_sd_transfer(SSIPeripheral *dev, uint32_t val) > s->response[1] = status; > DPRINTF("Card status 0x%02x\n", status); > } > - s->mode = SSI_SD_RESPONSE; > + s->mode = SSI_SD_PREP_RESP; > s->response_pos = 0; > } else { > s->cmdarg[s->arglen++] = val; > } > return 0xff; > + case SSI_SD_PREP_RESP: > + DPRINTF("Prepare card response (Ncr)\n"); > + s->mode = SSI_SD_RESPONSE; > + return 0xff; > case SSI_SD_RESPONSE: > if (s->stopping) { > s->stopping = 0; >
diff --git a/hw/sd/ssi-sd.c b/hw/sd/ssi-sd.c index 9a75e0095c..043e270066 100644 --- a/hw/sd/ssi-sd.c +++ b/hw/sd/ssi-sd.c @@ -36,6 +36,7 @@ do { fprintf(stderr, "ssi_sd: error: " fmt , ## __VA_ARGS__);} while (0) typedef enum { SSI_SD_CMD = 0, SSI_SD_CMDARG, + SSI_SD_PREP_RESP, SSI_SD_RESPONSE, SSI_SD_DATA_START, SSI_SD_DATA_READ, @@ -163,12 +164,16 @@ static uint32_t ssi_sd_transfer(SSIPeripheral *dev, uint32_t val) s->response[1] = status; DPRINTF("Card status 0x%02x\n", status); } - s->mode = SSI_SD_RESPONSE; + s->mode = SSI_SD_PREP_RESP; s->response_pos = 0; } else { s->cmdarg[s->arglen++] = val; } return 0xff; + case SSI_SD_PREP_RESP: + DPRINTF("Prepare card response (Ncr)\n"); + s->mode = SSI_SD_RESPONSE; + return 0xff; case SSI_SD_RESPONSE: if (s->stopping) { s->stopping = 0;