Re: [PATCH v2 6/8] hw/sd: sd: Actually perform the erase operation

[Bin Meng]

On Sat, Feb 20, 2021 at 6:28 AM Philippe Mathieu-Daudé <f4bug@amsat.org> wrote:
>
> On 2/16/21 4:02 PM, Bin Meng wrote:
> > From: Bin Meng <bin.meng@windriver.com>
> >
> > At present the sd_erase() does not erase the requested range of card
> > data to 0xFFs. Let's make the erase operation actually happen.
> >
> > Signed-off-by: Bin Meng <bin.meng@windriver.com>
> >
> > ---
> >
> > Changes in v2:
> > - honor the write protection bits for SDSC cards
> >
> >  hw/sd/sd.c | 22 ++++++++++++++--------
> >  1 file changed, 14 insertions(+), 8 deletions(-)
> >
> > diff --git a/hw/sd/sd.c b/hw/sd/sd.c
> > index f1f98bdec3..b386f16fcb 100644
> > --- a/hw/sd/sd.c
> > +++ b/hw/sd/sd.c
> > @@ -766,6 +766,9 @@ static void sd_erase(SDState *sd)
> >      uint64_t erase_start = sd->erase_start;
> >      uint64_t erase_end = sd->erase_end;
> >      bool sdsc = true;
> > +    uint64_t wpnum;
> > +    uint64_t erase_addr;
> > +    int erase_len = 1 << HWBLOCK_SHIFT;
> >
> >      trace_sdcard_erase(sd->erase_start, sd->erase_end);
> >      if (sd->erase_start == INVALID_ADDRESS
> > @@ -794,17 +797,20 @@ static void sd_erase(SDState *sd)
> >      sd->erase_end = INVALID_ADDRESS;
> >      sd->csd[14] |= 0x40;
> >
> > -    /* Only SDSC cards support write protect groups */
> > -    if (sdsc) {
> > -        erase_start = sd_addr_to_wpnum(erase_start);
> > -        erase_end = sd_addr_to_wpnum(erase_end);
> > -
> > -        for (i = erase_start; i <= erase_end; i++) {
> > -            assert(i < sd->wpgrps_size);
> > -            if (test_bit(i, sd->wp_groups)) {
> > +    memset(sd->data, 0xff, erase_len);
> > +    erase_addr = erase_start;
> > +    for (i = 0; i <= (erase_end - erase_start) / erase_len; i++) {
> > +        if (sdsc) {
> > +            /* Only SDSC cards support write protect groups */
> > +            wpnum = sd_addr_to_wpnum(erase_addr);
> > +            assert(wpnum < sd->wpgrps_size);
> > +            if (test_bit(wpnum, sd->wp_groups)) {
> >                  sd->card_status |= WP_ERASE_SKIP;
> > +                continue;
>
> So if a group is protected, you skip it but don't increase erase_addr.
> If G#4 is protected and G#5 isn't, when you check G#5 you end erasing
> G#4.
>

Oops, good catch!

I will send v2.

> >              }
> >          }
> > +        BLK_WRITE_BLOCK(erase_addr, erase_len);
> > +        erase_addr += erase_len;
> >      }
> >  }

Regards,
Bin