Re: [Qemu-devel] Missing Diag/Debug Registers in lsi53c895a emulation

[Paolo Bonzini <pbonzini@redhat.com>]

On 12/01/2015 10:39, Peter Lieven wrote:
> On 12.01.2015 10:28, Peter Lieven wrote:
>> Hi,
>>
>> while trying to run an ASA1000V appliance I found that registers 0x09
>> and 0x3c-3f are read during boot up. Which
>> currently results in an exit(1). The appliance uses an quite ancient
>> 2.6.29.6 Linux kernel.
>> These registers are mainly for diag and debug purposes so I came up
>> with the following patch. The system works
>> with the following patch, but I wonder if this is a correct workaround:
> 
> Maybe this is better:
> 
> diff --git a/hw/scsi/lsi53c895a.c b/hw/scsi/lsi53c895a.c
> index ec92048..db7d4b8 100644
> --- a/hw/scsi/lsi53c895a.c
> +++ b/hw/scsi/lsi53c895a.c
> @@ -277,6 +277,7 @@ typedef struct {
>      uint32_t csbc;
>      uint32_t scratch[18]; /* SCRATCHA-SCRATCHR */
>      uint8_t sbr;
> +    uint32_t adder;
> 
>      /* Script ram is stored as 32-bit words in host byteorder.  */
>      uint32_t script_ram[2048];
> @@ -1389,6 +1390,7 @@ again:
>                  switch ((insn >> 27) & 7) {
>                  case 0: /* Jump */
>                      DPRINTF("Jump to 0x%08x\n", addr);
> +                    s->adder = addr;
>                      s->dsp = addr;
>                      break;
>                  case 1: /* Call */
> @@ -1513,6 +1515,8 @@ static uint8_t lsi_reg_readb(LSIState *s, int offset)
>          return 0x7f;
>      case 0x08: /* Revision ID */
>          return 0x00;
> +    case 0x09: /* SOCL */
> +        return s->socl;
>      case 0xa: /* SSID */
>          return s->ssid;
>      case 0xb: /* SBCL */
> @@ -1577,6 +1581,8 @@ static uint8_t lsi_reg_readb(LSIState *s, int offset)
>          return s->sbr;
>      case 0x3b: /* DCNTL */
>          return s->dcntl;
> +    /* ADDER Output (Debug of relative jump address) */
> +    CASE_GET_REG32(adder, 0x3c)
>      case 0x40: /* SIEN0 */
>          return s->sien0;
>      case 0x41: /* SIEN1 */
> 

This looks good.  Can you send it with SoB and git-format-patch?

Paolo