Hi Joe,
On Tue, Sep 29, 2020 at 05:28:35PM -0700, Joe Komlodi wrote:
> Numonyx chips determine the number of cycles to wait based on bits 7:4 in the
> volatile configuration register.
>
> However, if these bits are 0x0 or 0xF, the number of dummy cycles to wait is
> 10 on a QIOR or QIOR4 command, or 8 on any other currently supported
> fast read command. [1]
>
> [1] http://www.micron.com/-/media/client/global/documents/products/
> data-sheet/nor-flash/serial-nor/n25q/n25q_512mb_1_8v_65nm.pdf
>
> Page 22 note 2, and page 30 notes 5 and 10.
>
> Signed-off-by: Joe Komlodi <koml...@xilinx.com>
> ---
> hw/block/m25p80.c | 26 +++++++++++++++++++++++---
> 1 file changed, 23 insertions(+), 3 deletions(-)
>
> diff --git a/hw/block/m25p80.c b/hw/block/m25p80.c
> index 483925f..43830c9 100644
> --- a/hw/block/m25p80.c
> +++ b/hw/block/m25p80.c
> @@ -820,6 +820,26 @@ static void reset_memory(Flash *s)
> trace_m25p80_reset_done(s);
> }
>
> +static uint8_t numonyx_fast_read_num_dummies(Flash *s)
Should we rename the function to something like
'numonyx_extract_cfg_num_dummies' (since it is not only used inside
'decode_fast_read_cmd')?
> +{
> + uint8_t cycle_count;
> + uint8_t num_dummies;
> + assert(get_man(s) == MAN_NUMONYX);
> +
> + cycle_count = extract32(s->volatile_cfg, 4, 4);
> + if (cycle_count == 0x0 || cycle_count == 0x0F) {
> + if (s->cmd_in_progress == QIOR || s->cmd_in_progress == QIOR4) {
QOR and QOR4 also has 10 dummy cycles on default so we will have to check for
those aswell, perhaps something similar like below migth work:
uint8_t n_dummies = extract32(s->volatile_cfg, 4, 4);
if (!n_dummies || n_dummies == 0xF) {
switch(s->cmd_in_progress){
case QOR:
case QOR4
case QIOR:
case QIOR4:
n_dummies = 10;
break;
default:
n_dummies = 8;
break;
}
}
return n_dummies;
Best regards,
Francisco Iglesias
> + num_dummies = 10;
> + } else {
> + num_dummies = 8;
> + }
> + } else {
> + num_dummies = cycle_count;
> + }
> +
> + return num_dummies;
> +}
> +
> static void decode_fast_read_cmd(Flash *s)
> {
> s->needed_bytes = get_addr_length(s);
> @@ -829,7 +849,7 @@ static void decode_fast_read_cmd(Flash *s)
> s->needed_bytes += 8;
> break;
> case MAN_NUMONYX:
> - s->needed_bytes += extract32(s->volatile_cfg, 4, 4);
> + s->needed_bytes += numonyx_fast_read_num_dummies(s);
> break;
> case MAN_MACRONIX:
> if (extract32(s->volatile_cfg, 6, 2) == 1) {
> @@ -868,7 +888,7 @@ static void decode_dio_read_cmd(Flash *s)
> );
> break;
> case MAN_NUMONYX:
> - s->needed_bytes += extract32(s->volatile_cfg, 4, 4);
> + s->needed_bytes += numonyx_fast_read_num_dummies(s);
> break;
> case MAN_MACRONIX:
> switch (extract32(s->volatile_cfg, 6, 2)) {
> @@ -908,7 +928,7 @@ static void decode_qio_read_cmd(Flash *s)
> );
> break;
> case MAN_NUMONYX:
> - s->needed_bytes += extract32(s->volatile_cfg, 4, 4);
> + s->needed_bytes += numonyx_fast_read_num_dummies(s);
> break;
> case MAN_MACRONIX:
> switch (extract32(s->volatile_cfg, 6, 2)) {
> --
> 2.7.4
>
