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Re: [Qemu-devel] [PATCH v4 05/11] block: m25p80: 4byte address mode
From: |
Krzeminski, Marcin (Nokia - PL/Wroclaw) |
Subject: |
Re: [Qemu-devel] [PATCH v4 05/11] block: m25p80: 4byte address mode |
Date: |
Fri, 18 Mar 2016 13:00:03 +0000 |
> -----Original Message-----
> From: EXT Peter Crosthwaite [mailto:address@hidden
> Sent: Thursday, March 17, 2016 6:27 PM
> To: Krzeminski, Marcin (Nokia - PL/Wroclaw)
> <address@hidden>
> Cc: address@hidden Developers <address@hidden>;
> Cédric Le Goater <address@hidden>; address@hidden
> Subject: Re: [PATCH v4 05/11] block: m25p80: 4byte address mode
>
> On Mon, Feb 22, 2016 at 12:03 AM, <address@hidden> wrote:
> > From: Marcin Krzeminski <address@hidden>
> >
> > This patch adds only 4byte address mode (does not cover dummy cycles).
> > This mode is needed to access more than 16 MiB of flash.
> >
> > Signed-off-by: Marcin Krzeminski <address@hidden>
> > ---
> > hw/block/m25p80.c | 41 +++++++++++++++++++++++++++++++++++-----
> -
> > 1 file changed, 35 insertions(+), 6 deletions(-)
> >
> > diff --git a/hw/block/m25p80.c b/hw/block/m25p80.c index
> > 0540dde..0698e7b 100644
> > --- a/hw/block/m25p80.c
> > +++ b/hw/block/m25p80.c
> > @@ -237,6 +237,9 @@ typedef enum {
> > ERASE_32K = 0x52,
> > ERASE_SECTOR = 0xd8,
> >
> > + EN_4BYTE_ADDR = 0xB7,
> > + EX_4BYTE_ADDR = 0xE9,
> > +
> > EXTEND_ADDR_READ = 0xC8,
> > EXTEND_ADDR_WRITE = 0xC5,
> >
> > @@ -269,6 +272,7 @@ typedef struct Flash {
> > uint8_t cmd_in_progress;
> > uint64_t cur_addr;
> > bool write_enable;
> > + bool four_bytes_address_mode;
> > bool reset_enable;
> > uint8_t ear;
> >
> > @@ -406,12 +410,25 @@ void flash_write8(Flash *s, uint64_t addr, uint8_t
> data)
> > s->dirty_page = page;
> > }
> >
> > +static inline int get_addr_length(Flash *s) {
> > + return s->four_bytes_address_mode ? 4 : 3; }
> > +
> > 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;
> > + int i;
> > +
> > + s->cur_addr = 0;
> > +
> > + for (i = 0; i < get_addr_length(s); ++i) {
> > + s->cur_addr <<= 8;
> > + s->cur_addr |= s->data[i];
> > + }
> > +
> > + if (get_addr_length(s) == 3) {
> > + s->cur_addr += (s->ear & 0x3) * MAX_3BYTES_SIZE;
> > + }
> >
> > s->state = STATE_IDLE;
> >
> > @@ -452,6 +469,7 @@ static void reset_memory(Flash *s)
> > s->cmd_in_progress = NOP;
> > s->cur_addr = 0;
> > s->ear = 0;
> > + s->four_bytes_address_mode = false;
> > s->len = 0;
> > s->needed_bytes = 0;
> > s->pos = 0;
> > @@ -480,7 +498,7 @@ static void decode_new_cmd(Flash *s, uint32_t
> value)
> > case DPP:
> > case QPP:
> > case PP:
> > - s->needed_bytes = 3;
> > + s->needed_bytes = get_addr_length(s);
> > s->pos = 0;
> > s->len = 0;
> > s->state = STATE_COLLECTING_DATA; @@ -489,7 +507,7 @@ static
> > void decode_new_cmd(Flash *s, uint32_t value)
> > case FAST_READ:
> > case DOR:
> > case QOR:
> > - s->needed_bytes = 4;
> > + s->needed_bytes = get_addr_length(s);
>
> You fix this later with the configuration of dummy cycles, but you should
> preserve the existing behaviour until your fix lands. This means that you
> should have +1 here.
True, all is that because there is a 11 patches for one file. From logical
point of view
this make sense, but from device emulation point of view applying not whole
series it does not.
>
> > s->pos = 0;
> > s->len = 0;
> > s->state = STATE_COLLECTING_DATA; @@ -502,6 +520,8 @@ static
> > void decode_new_cmd(Flash *s, uint32_t value)
> > s->needed_bytes = 4;
> > break;
> > case JEDEC_NUMONYX:
> > + s->needed_bytes = get_addr_length(s);
> > + break;
>
> This change ...
>
> > default:
> > s->needed_bytes = 5;
>
> Should be here, with a +2 (I think?).
Yes, but I would not prefer this in default, but since there is not much time
and it
does not change functionality I will put all in default, but change it with
Macronix
and Spansion future patch series (for those I reworked a bit all that switches
so it is
already changed there).
Thanks,
Marcin
>
> > }
> > @@ -517,6 +537,8 @@ static void decode_new_cmd(Flash *s, uint32_t
> value)
> > s->needed_bytes = 6;
> > break;
> > case JEDEC_NUMONYX:
> > + s->needed_bytes = get_addr_length(s);
> > + break;
>
> Similar.
>
> Otherwise,
>
> Reviewed-by: Peter Crosthwaite <address@hidden>
>
> Regards,
> Peter
>
> > default:
> > s->needed_bytes = 8;
> > }
> > @@ -575,6 +597,12 @@ static void decode_new_cmd(Flash *s, uint32_t
> value)
> > break;
> > case NOP:
> > break;
> > + case EN_4BYTE_ADDR:
> > + s->four_bytes_address_mode = true;
> > + break;
> > + case EX_4BYTE_ADDR:
> > + s->four_bytes_address_mode = false;
> > + break;
> > case EXTEND_ADDR_READ:
> > s->data[0] = s->ear;
> > s->pos = 0;
> > @@ -724,6 +752,7 @@ static const VMStateDescription vmstate_m25p80 =
> {
> > VMSTATE_UINT8(cmd_in_progress, Flash),
> > VMSTATE_UINT64(cur_addr, Flash),
> > VMSTATE_BOOL(write_enable, Flash),
> > + VMSTATE_BOOL(four_bytes_address_mode, Flash),
> > VMSTATE_UINT8(ear, Flash),
> > VMSTATE_BOOL(reset_enable, Flash),
> > VMSTATE_END_OF_LIST()
> > --
> > 2.5.0
> >