[flashrom] [PATCH] dummyflasher: Add a status register to SPI chips.

[Carl-Daniel Hailfinger]

Am 31.01.2012 06:51 schrieb Stefan Tauner:
> This is just a quick hack, that could be expanded. What do you think?
>
> Signed-off-by: Stefan Tauner <stefan.tauner at student.tuwien.ac.at>

Very good idea!

> --- a/dummyflasher.c
> +++ b/dummyflasher.c
> @@ -55,6 +55,7 @@ static unsigned int emu_jedec_be_52_size = 0;
>  static unsigned int emu_jedec_be_d8_size = 0;
>  static unsigned int emu_jedec_ce_60_size = 0;
>  static unsigned int emu_jedec_ce_c7_size = 0;
> +static uint8_t emu_status = 0;
>  #endif
>  #endif
>  
> @@ -126,6 +127,9 @@ int dummy_init(void)
>  {
>  	char *bustext = NULL;
>  	char *tmp = NULL;
> +#if EMULATE_SPI_CHIP
> +	char *status = NULL;
> +#endif
>  #if EMULATE_CHIP
>  	struct stat image_stat;
>  #endif
> @@ -178,6 +182,14 @@ int dummy_init(void)
>  		goto dummy_init_out;
>  	}
>  #if EMULATE_SPI_CHIP
> +	status = extract_programmer_param("status");
> +	if (status) {
> +		emu_status = atoi(status);
> +		msg_pdbg("Initial status register is set to 0x%02x.\n",
> +			 emu_status);
> +		free(status);
> +	}
> +
>  	if (!strcmp(tmp, "M25P10.RES")) {
>  		emu_chip = EMULATE_ST_M25P10_RES;
>  		emu_chip_size = 128 * 1024;
> @@ -385,10 +397,26 @@ static int emulate_spi_chip_response(unsigned int writecnt,
>  		if (readcnt > 2)
>  			readarr[2] = 0x4a;
>  		break;
> -	case JEDEC_RDSR:
> -		memset(readarr, 0, readcnt);
> +	case JEDEC_RDSR: {
> +		uint8_t tmp_status = emu_status;
>  		if (aai_active)
> -			memset(readarr, 1 << 6, readcnt);
> +			tmp_status |= 1 << 6;

The WIP (write in progress) / WEL (write enable latch) /AIP (AAI in
progress) logic should be moved to the respective commands so RDSR just does
memset(readarr, emu_status, readcnt);

> +		memset(readarr, tmp_status, readcnt);
> +		break;
> +	}
> +	case JEDEC_WREN:
> +		emu_status |= (1 << 1);
> +		break;
> +	case JEDEC_WRSR:
> +		if (!(emu_status & (1 << 1))) {
> +			msg_perr("WRSR attempted, but WEL is 0!\n");
> +			return 1;

Don't return 1 because a real chip wouldn't return an error either, it
would just ignore the command.

> +		}
> +		if (aai_active) {
> +			msg_perr("WRSR attempted during AAI sequence!\n");
> +			return 1;

dito.


> +		}
> +		emu_status = writearr[1] & 0xFC; /* resets WEL and WIP */
>  		break;
>  	case JEDEC_READ:
>  		offs = writearr[1] << 16 | writearr[2] << 8 | writearr[3];

After the end of the switch statement we should clear WEL if the command
was not WREN/EWSR.

Regards,
Carl-Daniel

-- 
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