[Qemu-devel] Re: [PATCHv3 17/20] eepro100: New function for reading command block

["Michael S. Tsirkin" <mst@redhat.com>]

On Tue, Mar 02, 2010 at 10:37:57PM +0100, Stefan Weil wrote:
> Move code which reads the command block to the
> new function read_cb. The patch also fixes some
> endianess issues related to the command block
> and moves declarations of local variables to
> the beginning of the block.
> 
> Signed-off-by: Stefan Weil <weil@mail.berlios.de>
> ---
>  hw/eepro100.c |   42 ++++++++++++++++++++++++++++--------------
>  1 files changed, 28 insertions(+), 14 deletions(-)
> 
> diff --git a/hw/eepro100.c b/hw/eepro100.c
> index f5aa306..e10ce62 100644
> --- a/hw/eepro100.c
> +++ b/hw/eepro100.c
> @@ -798,6 +798,16 @@ static void dump_statistics(EEPRO100State * s)
>      //~ missing("CU dump statistical counters");
>  }
>  
> +static void read_cb(EEPRO100State *s)
> +{
> +    cpu_physical_memory_read(s->cb_address, (uint8_t *) &s->tx, sizeof(s->tx));
> +    s->tx.status = le16_to_cpu(s->tx.status);
> +    s->tx.command = le16_to_cpu(s->tx.command);
> +    s->tx.link = le32_to_cpu(s->tx.link);
> +    s->tx.tbd_array_addr = le32_to_cpu(s->tx.tbd_array_addr);
> +    s->tx.tcb_bytes = le16_to_cpu(s->tx.tcb_bytes);
> +}
> +
>  static void tx_command(EEPRO100State *s)
>  {
>      uint32_t tbd_array = le32_to_cpu(s->tx.tbd_array_addr);
> @@ -901,21 +911,25 @@ static void set_multicast_list(EEPRO100State *s)
>  static void action_command(EEPRO100State *s)
>  {
>      for (;;) {
> -        s->cb_address = s->cu_base + s->cu_offset;
> -        cpu_physical_memory_read(s->cb_address, (uint8_t *)&s->tx, sizeof(s->tx));
> -        uint16_t command = le16_to_cpu(s->tx.command);
> -        s->tx.status = le16_to_cpu(s->tx.status);
> -        logout("val=(cu start), status=0x%04x, command=0x%04x, link=0x%08x\n",
> -               s->tx.status, command, s->tx.link);
> -        bool bit_el = ((command & COMMAND_EL) != 0);
> -        bool bit_s = ((command & COMMAND_S) != 0);
> -        bool bit_i = ((command & COMMAND_I) != 0);
> -        bool bit_nc = ((command & COMMAND_NC) != 0);
> +        bool bit_el;
> +        bool bit_s;
> +        bool bit_i;
> +        bool bit_nc;
>          bool success = true;
> -        //~ bool bit_sf = ((command & COMMAND_SF) != 0);
> -        uint16_t cmd = command & COMMAND_CMD;
> -        s->cu_offset = le32_to_cpu(s->tx.link);
> -        switch (cmd) {
> +        s->cb_address = s->cu_base + s->cu_offset;
> +        read_cb(s);
> +        bit_el = ((s->tx.command & COMMAND_EL) != 0);
> +        bit_s = ((s->tx.command & COMMAND_S) != 0);
> +        bit_i = ((s->tx.command & COMMAND_I) != 0);
> +        bit_nc = ((s->tx.command & COMMAND_NC) != 0);

() is never needed around the assigned value.  this can be fixed
separately though.  AFAIK you also do not need != : values are coersed
by assignment to bool correctly.
Again, can be fixed separately.

> +#if 0
> +        bool bit_sf = ((s->tx.command & COMMAND_SF) != 0);
> +#endif

Is the above likely to be useful?

> +        s->cu_offset = s->tx.link;
> +        TRACE(OTHER,
> +              logout("val=(cu start), status=0x%04x, command=0x%04x, link=0x%08x\n",
> +                     s->tx.status, s->tx.command, s->tx.link));
> +        switch (s->tx.command & COMMAND_CMD) {
>          case CmdNOp:
>              /* Do nothing. */
>              break;
> -- 
> 1.7.0