Re: [Qemu-devel] [PATCH v2 04/11] block: m25p80: Extend address mode

[Cédric Le Goater]

On 02/04/2016 01:23 PM, address@hidden wrote:
> From: Marcin Krzeminski <address@hidden>
> 
> Extend address mode allows to switch flash 16 MiB banks,
> allowing user to access all flash sectors.
> This access mode is used by u-boot.
> 
> Signed-off-by: Marcin Krzeminski <address@hidden>
> Reviewed-by: Peter Crosthwaite <address@hidden>
> ---
>  hw/block/m25p80.c | 27 +++++++++++++++++++++++++++
>  1 file changed, 27 insertions(+)
> 
> diff --git a/hw/block/m25p80.c b/hw/block/m25p80.c
> index f9088c5..6b5f00d 100644
> --- a/hw/block/m25p80.c
> +++ b/hw/block/m25p80.c
> @@ -48,6 +48,9 @@
>   */
>  #define WR_1 0x100
> 
> +/* 16 MiB max in 3 byte address mode */
> +#define MAX_3BYTES_SIZE 0x1000000
> +
>  typedef struct FlashPartInfo {
>      const char *part_name;
>      /* jedec code. (jedec >> 16) & 0xff is the 1st byte, >> 8 the 2nd etc */
> @@ -234,6 +237,9 @@ typedef enum {
>      ERASE_32K = 0x52,
>      ERASE_SECTOR = 0xd8,
> 
> +    EXTEND_ADDR_READ = 0xC8,
> +    EXTEND_ADDR_WRITE = 0xC5,
> +
>      RESET_ENABLE = 0x66,
>      RESET_MEMORY = 0x99,
>  } FlashCMD;
> @@ -264,6 +270,7 @@ typedef struct Flash {
>      uint64_t cur_addr;
>      bool write_enable;
>      bool reset_enable;
> +    uint8_t ear;
> 
>      int64_t dirty_page;
> 
> @@ -404,6 +411,7 @@ static void complete_collecting_data(Flash *s)
>      s->cur_addr = s->data[0] << 16;
>      s->cur_addr |= s->data[1] << 8;
>      s->cur_addr |= s->data[2];
> +        s->cur_addr += (s->ear & 0x3) * MAX_3BYTES_SIZE;

here ^

and this line does not appear in patch 5 which is curious. Is that a refresh 
issue ? 

Thanks,

C.

> 
>      s->state = STATE_IDLE;
> 
> @@ -431,6 +439,9 @@ static void complete_collecting_data(Flash *s)
>              s->write_enable = false;
>          }
>          break;
> +    case EXTEND_ADDR_WRITE:
> +        s->ear = s->data[0];
> +        break;
>      default:
>          break;
>      }
> @@ -440,6 +451,7 @@ static void reset_memory(Flash *s)
>  {
>      s->cmd_in_progress = NOP;
>      s->cur_addr = 0;
> +    s->ear = 0;
>      s->len = 0;
>      s->needed_bytes = 0;
>      s->pos = 0;
> @@ -563,6 +575,20 @@ static void decode_new_cmd(Flash *s, uint32_t value)
>          break;
>      case NOP:
>          break;
> +    case EXTEND_ADDR_READ:
> +        s->data[0] = s->ear;
> +        s->pos = 0;
> +        s->len = 1;
> +        s->state = STATE_READING_DATA;
> +        break;
> +    case EXTEND_ADDR_WRITE:
> +        if (s->write_enable) {
> +            s->needed_bytes = 1;
> +            s->pos = 0;
> +            s->len = 0;
> +            s->state = STATE_COLLECTING_DATA;
> +        }
> +        break;
>      case RESET_ENABLE:
>          s->reset_enable = true;
>          break;
> @@ -699,6 +725,7 @@ static const VMStateDescription vmstate_m25p80 = {
>          VMSTATE_UINT8(cmd_in_progress, Flash),
>          VMSTATE_UINT64(cur_addr, Flash),
>          VMSTATE_BOOL(write_enable, Flash),
> +        VMSTATE_UINT8(ear, Flash),
>          VMSTATE_BOOL(reset_enable, Flash),
>          VMSTATE_END_OF_LIST()
>      }
>