Re: [Qemu-devel] [PATCH v4 06/11] block: m25p80: Add configuration registers

[Peter Crosthwaite]

On Mon, Feb 22, 2016 at 12:03 AM,  <address@hidden> wrote:
> From: Marcin Krzeminski <address@hidden>
>
> This patch adds both volatile and non volatile configuration registers
> and commands to allow modify them. It is needed for proper handling
> dummy cycles. Initialization of those registers and flash state
> has been included as well.
> Some of this registers are used by kernel.
>
> Signed-off-by: Marcin Krzeminski <address@hidden>
> ---
>  hw/block/m25p80.c | 110 
> ++++++++++++++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 110 insertions(+)
>
> diff --git a/hw/block/m25p80.c b/hw/block/m25p80.c
> index 0698e7b..9d5a071 100644
> --- a/hw/block/m25p80.c
> +++ b/hw/block/m25p80.c
> @@ -26,6 +26,7 @@
>  #include "sysemu/block-backend.h"
>  #include "sysemu/blockdev.h"
>  #include "hw/ssi/ssi.h"
> +#include "qemu/bitops.h"
>
>  #ifndef M25P80_ERR_DEBUG
>  #define M25P80_ERR_DEBUG 0
> @@ -245,6 +246,15 @@ typedef enum {
>
>      RESET_ENABLE = 0x66,
>      RESET_MEMORY = 0x99,
> +
> +    RNVCR = 0xB5,
> +    WNVCR = 0xB1,
> +
> +    RVCR = 0x85,
> +    WVCR = 0x81,
> +
> +    REVCR = 0x65,
> +    WEVCR = 0x61,
>  } FlashCMD;
>
>  typedef enum {
> @@ -271,6 +281,9 @@ typedef struct Flash {
>      uint8_t needed_bytes;
>      uint8_t cmd_in_progress;
>      uint64_t cur_addr;
> +    uint32_t nonvolatile_cfg;
> +    uint32_t volatile_cfg;
> +    uint32_t enh_volatile_cfg;
>      bool write_enable;
>      bool four_bytes_address_mode;
>      bool reset_enable;
> @@ -459,6 +472,15 @@ static void complete_collecting_data(Flash *s)
>      case EXTEND_ADDR_WRITE:
>          s->ear = s->data[0];
>          break;
> +    case WNVCR:
> +        s->nonvolatile_cfg = s->data[0] | (s->data[1] << 8);
> +        break;
> +    case WVCR:
> +        s->volatile_cfg = s->data[0];
> +        break;
> +    case WEVCR:
> +        s->enh_volatile_cfg = s->data[0];
> +        break;
>      default:
>          break;
>      }
> @@ -477,6 +499,42 @@ static void reset_memory(Flash *s)
>      s->write_enable = false;
>      s->reset_enable = false;
>
> +    if (((s->pi->jedec >> 16) & 0xFF) == JEDEC_NUMONYX) {
> +        s->volatile_cfg = 0;
> +        /* WRAP & reserved*/

These bitfield masks and their values need some macrofication. Then
the comments explaining what bits are what can be dropped.

> +        s->volatile_cfg |= 0x3;

Why you set a reserved bit?

> +        /* XIP */
> +        if (extract32(s->nonvolatile_cfg, 9, 3) != 0x7) {

An example,
#define NVCFG_XIP_MODE_DISABLED 0x7

> +            s->volatile_cfg |= (1 << 3);
> +        }
> +        /* Number of dummy cycles */
> +        s->volatile_cfg |= deposit32(s->volatile_cfg,
> +                            4, 4, extract32(s->nonvolatile_cfg, 12, 4));
> +        s->enh_volatile_cfg = 0;
> +        /* Output driver strength */
> +        s->enh_volatile_cfg |= 0x7;
> +        /* Vpp accelerator */
> +        s->enh_volatile_cfg |= (1 << 3);

#define EVCFG_VPP_ACCELERATOR (1 << 3) ...

I am aware of my unreliability to get the review timely but the patch
intent looks good,

so with the macroification changes (globally to this function):

Acked-by: Peter Crosthwaite <address@hidden>

Regards,
Peter

> +        /* Reset/hold & reserved */
> +        s->enh_volatile_cfg |= (1 << 4);
> +        /* Dual I/O protocol */
> +        if ((s->nonvolatile_cfg >> 1) & 0x1) {
> +            s->enh_volatile_cfg |= (1 << 6);
> +        }
> +        /* Quad I/O protocol */
> +        if ((s->nonvolatile_cfg >> 3) & 0x1) {
> +            s->enh_volatile_cfg |= (1 << 7);
> +        }
> +
> +        if (!(s->nonvolatile_cfg & 0x1)) {
> +            s->four_bytes_address_mode = true;
> +        }
> +
> +        if (!((s->nonvolatile_cfg >> 1) & 0x1)) {
> +            s->ear = 0x3;
> +        }
> +    }
> +
>      DB_PRINT_L(0, "Reset done.\n");
>  }
>
> @@ -617,6 +675,49 @@ static void decode_new_cmd(Flash *s, uint32_t value)
>              s->state = STATE_COLLECTING_DATA;
>          }
>          break;
> +    case RNVCR:
> +        s->data[0] = s->nonvolatile_cfg & 0xFF;
> +        s->data[1] = (s->nonvolatile_cfg >> 8) & 0xFF;
> +        s->pos = 0;
> +        s->len = 2;
> +        s->state = STATE_READING_DATA;
> +        break;
> +    case WNVCR:
> +        if (s->write_enable) {
> +            s->needed_bytes = 2;
> +            s->pos = 0;
> +            s->len = 0;
> +            s->state = STATE_COLLECTING_DATA;
> +        }
> +        break;
> +    case RVCR:
> +        s->data[0] = s->volatile_cfg & 0xFF;
> +        s->pos = 0;
> +        s->len = 1;
> +        s->state = STATE_READING_DATA;
> +        break;
> +    case WVCR:
> +        if (s->write_enable) {
> +            s->needed_bytes = 1;
> +            s->pos = 0;
> +            s->len = 0;
> +            s->state = STATE_COLLECTING_DATA;
> +        }
> +        break;
> +    case REVCR:
> +        s->data[0] = s->enh_volatile_cfg & 0xFF;
> +        s->pos = 0;
> +        s->len = 1;
> +        s->state = STATE_READING_DATA;
> +        break;
> +    case WEVCR:
> +        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;
> @@ -738,6 +839,11 @@ static void m25p80_pre_save(void *opaque)
>      flash_sync_dirty((Flash *)opaque, -1);
>  }
>
> +static Property m25p80_properties[] = {
> +    DEFINE_PROP_UINT32("nonvolatile-cfg", Flash, nonvolatile_cfg, 0x8FFF),
> +    DEFINE_PROP_END_OF_LIST(),
> +};
> +
>  static const VMStateDescription vmstate_m25p80 = {
>      .name = "xilinx_spi",
>      .version_id = 2,
> @@ -755,6 +861,9 @@ static const VMStateDescription vmstate_m25p80 = {
>          VMSTATE_BOOL(four_bytes_address_mode, Flash),
>          VMSTATE_UINT8(ear, Flash),
>          VMSTATE_BOOL(reset_enable, Flash),
> +        VMSTATE_UINT32(nonvolatile_cfg, Flash),
> +        VMSTATE_UINT32(volatile_cfg, Flash),
> +        VMSTATE_UINT32(enh_volatile_cfg, Flash),
>          VMSTATE_END_OF_LIST()
>      }
>  };
> @@ -770,6 +879,7 @@ static void m25p80_class_init(ObjectClass *klass, void 
> *data)
>      k->set_cs = m25p80_cs;
>      k->cs_polarity = SSI_CS_LOW;
>      dc->vmsd = &vmstate_m25p80;
> +    dc->props = m25p80_properties;
>      mc->pi = data;
>  }
>
> --
> 2.5.0
>