Re: [Qemu-devel] [PATCH v3 05/13] tpm_tis: merge read and write buffer into single buffer

[Marc-André Lureau]

On Fri, Nov 10, 2017 at 3:11 PM, Stefan Berger
<address@hidden> wrote:
> Since we can only be in read or write mode, we can merge the buffers
> into a single buffer.
>
> Signed-off-by: Stefan Berger <address@hidden>

Reviewed-by: Marc-André Lureau <address@hidden>


> ---
>  hw/tpm/tpm_tis.c | 29 ++++++++++++++---------------
>  1 file changed, 14 insertions(+), 15 deletions(-)
>
> diff --git a/hw/tpm/tpm_tis.c b/hw/tpm/tpm_tis.c
> index f6f5f17..0b6dd7f 100644
> --- a/hw/tpm/tpm_tis.c
> +++ b/hw/tpm/tpm_tis.c
> @@ -70,8 +70,7 @@ typedef struct TPMState {
>      ISADevice busdev;
>      MemoryRegion mmio;
>
> -    unsigned char w_buffer[TPM_TIS_BUFFER_MAX];
> -    unsigned char r_buffer[TPM_TIS_BUFFER_MAX];
> +    unsigned char buffer[TPM_TIS_BUFFER_MAX];
>
>      uint8_t active_locty;
>      uint8_t aborting_locty;
> @@ -257,7 +256,7 @@ static void tpm_tis_tpm_send(TPMState *s, uint8_t locty)
>  {
>      TPMLocality *locty_data = &s->loc[locty];
>
> -    tpm_tis_show_buffer(s->w_buffer, s->be_buffer_size,
> +    tpm_tis_show_buffer(s->buffer, s->be_buffer_size,
>                          "tpm_tis: To TPM");
>
>      /*
> @@ -268,9 +267,9 @@ static void tpm_tis_tpm_send(TPMState *s, uint8_t locty)
>
>      s->cmd = (TPMBackendCmd) {
>          .locty = locty,
> -        .in = s->w_buffer,
> +        .in = s->buffer,
>          .in_len = locty_data->w_offset,
> -        .out = s->r_buffer,
> +        .out = s->buffer,
>          .out_len = s->be_buffer_size,
>      };
>
> @@ -422,7 +421,7 @@ static void tpm_tis_request_completed(TPMIf *ti)
>      s->loc[locty].r_offset = 0;
>      s->loc[locty].w_offset = 0;
>
> -    tpm_tis_show_buffer(s->r_buffer, s->be_buffer_size,
> +    tpm_tis_show_buffer(s->buffer, s->be_buffer_size,
>                          "tpm_tis: From TPM");
>
>      if (TPM_TIS_IS_VALID_LOCTY(s->next_locty)) {
> @@ -442,10 +441,10 @@ static uint32_t tpm_tis_data_read(TPMState *s, uint8_t 
> locty)
>      uint16_t len;
>
>      if ((s->loc[locty].sts & TPM_TIS_STS_DATA_AVAILABLE)) {
> -        len = MIN(tpm_cmd_get_size(&s->r_buffer),
> +        len = MIN(tpm_cmd_get_size(&s->buffer),
>                    s->be_buffer_size);
>
> -        ret = s->r_buffer[s->loc[locty].r_offset++];
> +        ret = s->buffer[s->loc[locty].r_offset++];
>          if (s->loc[locty].r_offset >= len) {
>              /* got last byte */
>              tpm_tis_sts_set(&s->loc[locty], TPM_TIS_STS_VALID);
> @@ -491,11 +490,11 @@ static void tpm_tis_dump_state(void *opaque, hwaddr 
> addr)
>              "tpm_tis: result buffer : ",
>              s->loc[locty].r_offset);
>      for (idx = 0;
> -         idx < MIN(tpm_cmd_get_size(&s->r_buffer), s->be_buffer_size);
> +         idx < MIN(tpm_cmd_get_size(&s->buffer), s->be_buffer_size);
>           idx++) {
>          DPRINTF("%c%02x%s",
>                  s->loc[locty].r_offset == idx ? '>' : ' ',
> -                s->r_buffer[idx],
> +                s->buffer[idx],
>                  ((idx & 0xf) == 0xf) ? "\ntpm_tis:                 " : "");
>      }
>      DPRINTF("\n"
> @@ -503,11 +502,11 @@ static void tpm_tis_dump_state(void *opaque, hwaddr 
> addr)
>              "tpm_tis: request buffer: ",
>              s->loc[locty].w_offset);
>      for (idx = 0;
> -         idx < MIN(tpm_cmd_get_size(s->w_buffer), s->be_buffer_size);
> +         idx < MIN(tpm_cmd_get_size(s->buffer), s->be_buffer_size);
>           idx++) {
>          DPRINTF("%c%02x%s",
>                  s->loc[locty].w_offset == idx ? '>' : ' ',
> -                s->w_buffer[idx],
> +                s->buffer[idx],
>                  ((idx & 0xf) == 0xf) ? "\ntpm_tis:                 " : "");
>      }
>      DPRINTF("\n");
> @@ -569,7 +568,7 @@ static uint64_t tpm_tis_mmio_read(void *opaque, hwaddr 
> addr,
>          if (s->active_locty == locty) {
>              if ((s->loc[locty].sts & TPM_TIS_STS_DATA_AVAILABLE)) {
>                  val = TPM_TIS_BURST_COUNT(
> -                       MIN(tpm_cmd_get_size(&s->r_buffer),
> +                       MIN(tpm_cmd_get_size(&s->buffer),
>                             s->be_buffer_size)
>                         - s->loc[locty].r_offset) | s->loc[locty].sts;
>              } else {
> @@ -922,7 +921,7 @@ static void tpm_tis_mmio_write(void *opaque, hwaddr addr,
>
>              while ((s->loc[locty].sts & TPM_TIS_STS_EXPECT) && size > 0) {
>                  if (s->loc[locty].w_offset < s->be_buffer_size) {
> -                    s->w_buffer[s->loc[locty].w_offset++] =
> +                    s->buffer[s->loc[locty].w_offset++] =
>                          (uint8_t)val;
>                      val >>= 8;
>                      size--;
> @@ -937,7 +936,7 @@ static void tpm_tis_mmio_write(void *opaque, hwaddr addr,
>                  /* we have a packet length - see if we have all of it */
>                  bool need_irq = !(s->loc[locty].sts & TPM_TIS_STS_VALID);
>
> -                len = tpm_cmd_get_size(&s->w_buffer);
> +                len = tpm_cmd_get_size(&s->buffer);
>                  if (len > s->loc[locty].w_offset) {
>                      tpm_tis_sts_set(&s->loc[locty],
>                                      TPM_TIS_STS_EXPECT | TPM_TIS_STS_VALID);
> --
> 2.5.5
>
>



-- 
Marc-André Lureau